ARTICLE IN PRESS Flora 202 (2007) 27–49 www.elsevier.de/flora Adaptive strategies in burned subtropical grassland in southern Brazil Gerhard Ernst Overbeck, Jörg Pfadenhauer Technische Universität München, An Hochanger 6, 85350 Freising-Weihenstephan, Germany Received 17 May 2005; accepted 2 November 2005 Abstract Extensive parts of subtropical South America are covered by grassland vegetation, despite climatic conditions that allow for forest development, and fire may have been an important factor in the evolutionary history of these grasslands. In a regularly burned grassland area, situated in a forest–grassland-mosaic near Porto Alegre, RS, Brazil, life form spectrum and plant species’ reaction to fire were examined, allowing for (1) a physiognomic description of the grassland, and (2) a functional classification of grassland species in relation to fire. Grassland sites with different time since the last fire occurred were compared between each other as well as to sites at the forest–grassland border. South Brazilian grassland is dominated by hemicryptophytic caespitose graminoids that resist fires, but contains a large number of geophytic or hemicryptophytic forbs, in general sprouting after fire. Shrubs, mostly sprouting species of the grassland community, were present with high cover values even in recently burned areas. In contrast to Central Brazilian Cerrado, trees were of little importance: most species found were forest pioneer species without the capacity to survive fires unless growing on sites protected from fire or at the forest border where burns stop. Non-sprouting species were of little importance in the community, and only two species found were therophytes. Lack of therophytes in South Brazilian grassland vegetation deserves further attention. r 2006 Elsevier GmbH. All rights reserved. Keywords: Campos; Fire; Life form; Plant functional type; Raunkiaer Introduction While savanna ecosystems cover large parts of tropical South America (e.g., Sarmiento 1990 for an overview), wide parts of northern Argentina and Uruguay are characterized by grasslands, extending around the Rı́o de la Plata and continuing in southern Brazil (Bilenca and Miñarro 2004; Soriano et al. 1992; Fig. 1). In southern Brazil, natural grasslands (‘‘Campos’’) can be found in the southermost state Rio Grande do Sul (RS; Fig. 2) and in the adjacent states of Santa Catarina (SC) and Paraná (PR). The total extension of Corresponding author. Fax: +09 8161 714143. E-mail address: overbeck@wzw.tum.de (G.E. Overbeck). 0367-2530/$ - see front matter r 2006 Elsevier GmbH. All rights reserved. doi:10.1016/j.flora.2005.11.004 the grasslands in those three states has been reduced from originally 218.700 km2 (Longhi-Wagner 2003) to today appoximately 136.800 km2 (Nabinger et al. 2000), principally due to expansion of agri- and silvicultural production. South Brazilian Campos grasslands, presenting a mixture of C4 and C3 grasses with C4 dominance, are under subtropical humid climate (Köppen’s Cfa) in southern RS state, and under warmtemperate humid climate on the highlands in northern RS and adjacent SC (Köppen’s Cfb; Moreno 1961), in the latter climatic region in mosaics with Araucaria forests (see Fig. 1). Precipitation in southern Brazil ranges from 1200 (southern RS) to over 2200 mm year1 (highest part of the planalto in northern RS), with no dry season. Hydric deficits may occasionally occur in the ARTICLE IN PRESS 28 G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 BRAZIL PARAGUAY 25° S 30° S URUGUAY ARGENTINA Porto Alegre 35° S Río de la Plata 40° S 0 500 1.000 km Fig. 1. Location of temperate and subtropical grasslands in southern South America, between 25 and 381S (both shades of gray). Grasslands south of the Rı́o de la Plata commonly are considered to be Pampas grassland; those north of the Rı́o de la Plata; Campos. Campos grasslands in Brazil depicted in darker shade gray (sources: Soriano et al. 1992 for Argentina and Uruguay; Leite 2002 for distribution of grasslands in Brazil, modified). Location of the study site in Porto Alegre Atlantic forest Semi-deciduous forest Araucaria forest Grassland Coastal vegetation Transitional vegetation on the southeastern shield (mosaics of grassland, shrublands and forests) 0 100 200 Fig. 2. Vegetation types in Brazil’s southernmost state, Rio Grande do Sul (from Pillar and Quadros 1997, modified). summer months, but current climatic conditions allow for forest development (Lindman 1906; Rambo 1956). Already Lindman (1906) had noted the contradiction between the presence of grassland vegetation in southern Brazil and humid climatic conditions that allow for forest development. Similarly, the presence of grasslands in a climate apparently supporting forest vegetation has led to intense debate of the so-called ‘‘Pampas problem’’ in the Rı́o de la Plata region (e.g., Box 1986; Eriksen 1978; Walter 1967). Discussion, however, focused on relations between climate and vegetation in a rather static view, neglecting vegetation history and the possibility of rather recent climatic changes. Phytogeographical and paleoecological data suggest that grasslands in southern Brazil are relicts of drier and cooler conditions during the last glacial and post-glacial periods, stabilized by herbivory and fire and subject to forest invasion only relatively recently (Behling 2002, 2004; Bigarella 1971; Klein 1975; Pillar and Quadros 1997; Rambo 1953, 1956). In contrast to South African savannas and grasslands, large native herbivores are largely missing: they became extinct as the result of climatic changes between the end of the last glaciation and 8000 years BP (Kern 1994), coninciding with the arrival of human populations in the region. The fire history of southern Brazil is poorly known. Palynological studies indicate that fire was rare during early post-glacial times, but became frequent about 7400 years ago (Behling et al. 2004), possibly as it may have been used as a tool for hunting by indigeneous people (Kern 1994). In Cerrado (Central Brazilian savannas), fire is considered to have been present long before human occupation, but frequency most probably has increased with anthropogenic use (Hoffmann and Moreira 2002; Miranda et al. 2002); the effect has been a stabilization of open vegetation formations by impeding establishment of forest species, and thus a change in physignomy (Hoffmann 1996, 2000; Mirelles et al. 1997). Recent modelling of the distribution of vegetation types in southern Africa in relation to climatic parameters and fire has shown that in regions above a certain limit of precipitation (approx. 650 mm for southern Africa), not climatic conditions, but presence of fire determines vegetation physiognomy, independent of historic human action (Bond et al. 2003). While less data are available for southern Brazil, the situation likely is similar. Few studies have been conducted on the effect of fire on grassland communities in southern Brazil. Single fire events do not invoke major overall compositional changes (Eggers and Porto 1994), and fire has been shown to increase small-scale and short-term diversity (Overbeck et al. 2005). Adaptations of South Brazilian Campos species have not been studied explicitly so far. A number of classification systems for plant adapations exist, including some specifically related to fire. Noble and Slatyer (1980) have presented a general model of plant strategies in respect to fire, focusing on regeneration or colonization attributes; application of this model to a community, however, requires detailed information ARTICLE IN PRESS G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 on life cycle, persistance and dispersal abilities of the species present. Plants from fire-prone communities commonly can be classified according to the two criteria survival of fire and reproductive response to fire (Bond and Van Wilgen 1996). For consideration primarily of survival of fire, plants in fire-prone habitats have been grouped into plants resisting fire with part of their aboveground biomass (‘‘resisters’’, Rowe 1983), plants dying back completely aboveground, but surviving due to insulation of buds by the soil (‘‘endurers’’, Rowe 1983; ‘‘sprouters’’, Bond and Van Wilgen 1996) and into plants having to germinate either from the seed bank (‘‘evaders’’, Rowe 1983) or from newly dispersed seeds (‘‘invaders’’, Rowe 1983). If recruitment occurs only right after a fire event, non-sprouters have been termed ‘‘fire-recruiters’’ (as opposed to ‘‘fire-persisters’’; Keeley 1992). Similarily, chaparral species have been categorized into ‘‘obligate seeders’’, ‘‘obligate resprouters’’ and ‘‘facultative seeders/facultative resprouters’’ (e.g., Franklin et al. 2004; Keeley 1986, 1992). In poorly known florae information on germination requirements usually is unavailable for the majority of species, while position and protection of regenerative buds can be observed more readily. This is the principal criterion in one of the classical functional type systems: Raunkiaer’s life form spectrum (Raunkiaer 1934), applied for prediction of climate in many ecosystems of the world (see Cain 1950 for a compilation of life form spectra for various climatic regions) and considered to be a good predictor of disturbance (McIntyre et al. 1999). The growth form system, an essentially synonymous (Pillar and Orlóci 2004), but somewhat less strict classification as not based on a clear criterion but on general plant architecture, has been identified to be a useful framework for classification into plant functional types in various systems (e.g., Chapin et al. 1996; Diaz and Cabido 1997; McIntyre et al. 1995). Raunkiaer’s life form system has been applied to fire-prone systems (Batalha and Martins 2002; Chapman and Crow 1981), but applicability of the system specifically to fire has never been evaluated. In this paper, we present the physiognomic composition of a grassland community subject to frequent burns in southern Brazil, and discuss functional attributes in relation to fire, evaluating applicability of the classical life form system and linking it to the main post-fire regeneration mechanisms in an alternative classification. This allows to describe the structure of the grasslands via the physiognomic information given by Raunkiaer’s system, while being able to discuss regeneration responses in relation to fire. Further, we characterize the principal plant types present in a brief, reviewlike way and compare the in general still poorly studied South Brazilian Campos grassland with other burned grassland systems concerning life form composition. 29 Methods Study site Field work was carried out on Morro Santana, Porto Alegre, RS, Brazil. Morro Santana (301030 S, 511070 W, max. alt. 311 m a.s.l.), situated at the northern limit of the Crystalline shield in RS, is covered by a mosaic of forests (Atlantic forest) and grasslands. Floristic composition of the grassland area has been presented in Overbeck et al. (2006a). The grasslands are species rich, with a total of 430 species identified so far in an area of about 220 ha, from a species pool of about 450–500 species. Borders between forest and grasslands have been remarkably stable in the past decades, due to frequent fires which prevent expansion of forest into grassland. Isolated patches of shrubs and trees, considered nuclei of forest establishment, can be found principally in areas with rock outcrops. Presence of fire, today anthropogenic, throughout the past 1200 years has been confirmed by a palynological study (Behling et al., in press). Data collection Six pairs of transects (distance between transects in each pair approximately 5 m) were installed from the forest border into the grassland, in areas differing in slope, aspect, degree of shrub encroachment and time since the last fire. In October 2002, one transect in each of the pairs was subjected to an experimental burn; however, in two of the transects, situated in areas that had burned almost 1 year before, the fire did not spread due to lack of continuous biomass. This left us with four transects burned in our experiments (group 1), four transects burned a year before (group 2) and four transects burned 3 or more years before (group 3). To be able to sample both the herbaceous stratum and characterize woody species distribution, we used a stratified plot design. Each transect consisted of seven contiguous large plots (LPs) of 4.5 m  4.5 m. The first plot, situated directly at the forest–grassland border, did not burn in any of the transects. Within LPs, three contiguous medium-sized plots (MPs) of 1.5 m  1.5 m were marked, totalling 21 contiguous plots from the border into the grassland for each transect. In LPs, all woody vegetation components (trees and shrubs) with height above 80 cm were recorded (number of individuals per species), whereas in MPs, cover of all woody individuals above 10 cm was recorded, using the Londo (1976) decimal scale. Floristic composition of the herbaceous layer was sampled in three small contiguous plots (SPs) of 50 cm  50 cm, marked in the center of LPs 1, 3, 5 and 7 (1 being closest, 7 farthest to the forest border), using the Londo (1976) decimal scale. ARTICLE IN PRESS 30 G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Additionally, cover of litter, rocks, mosses, open soil and total cover of standing dead biomass were recorded in SPs, while in MPs and LPs, total cover of herbs, grasses (divided into living and dead), lianas, rocks, mosses, litter and open soil and medium height of the herbaceous stratum recorded. All surveys were conducted 2–3 months after the experimental fire. Additional structural surveys in MPs and LPs had also been conducted directly before, and, in burned plots, 1 week after the experimental burns. Data analysis Data from the three contiguous SPs was pooled to one plot of 0.75 m2 by taking the mean value across plots for each species or structural category. Species were grouped into life forms according to Raunkiaer’s (1934) system, with a modified classification into subgroups (Table 1). Plants were grouped a posteriori, i.e. according to potential life form of the species. Instead of grouping woody species into phanerophytes and chamaephytes as in Raunkiaer’s system, they were categorized into the growth form categories shrubs and trees, considered to reflect differences in plant carbon allocation strategy (Bond and Midgley 2000; see also Sarmiento and Monasterio 1983), thus avoiding the necessity to fix a height limit between the two groups, which would be arbitrary in subtropical vegetation. We then modified this system according to survival capacity to fire, obtaining the classification into fire life forms presented in Table 3. In this new classification, position of the buds (Raunkiaer’s criterion) is joined by information on whether the plant dies (non-sprouter), looses its aboveground biomass but can recover from belowground organs (sprouter) or manages to keep at least some aboveground biomass (resister) during a fire. No evidence of stimulation of heat germination by fire (as known for many hardseeded shrubs in mediterranean climate regions, e.g. Keeley and Fotheringham Table 1. 2000) exists for the studied region (Overbeck et al., 2006b); thus, it was not necessary (nor possible due to information limited to a few species only) to include an attribute for this in the classification. For both Raunkiaer’s system and the fire life form classification, individual species cover values were summed up to the corresponding life form category and then the relative cover of each category in relation to total vegetation cover was calculated, allowing for comparison of areas contrasting greatly in total vegetation cover in relation to time since the last burn. Species that had not been identified to the species level and could not be safely assigned to any life form group were considered as part of total vegetation cover in calculation of relative cover values of each life form group, but otherwise left out from the analyses (0.58% of sum of all frequencies). The three plot groups representing different time since the last fire were compared for differences between performance of each life form and fire life form, using univariate analysis of variance with randomization testing (MULTIV software, Pillar 2004; Euclidean distance as resemblance measure, a ¼ 0:05 as probability limit for rejection of null-hypothesis). Cover of standing dead biomass was treated the same way. Further, border plots were compared to grassland plots taken as a group. In addition to the vegetation life form spectrum based on relative cover values, a floristic life form spectrum based on species number per life form group was elaborated. For MP and LP data, species were grouped into shrubs and trees (growth forms), into species commonly known as grassland species, forest border species, or as forest species (successional groups) and into species with or without sprouting capacity after fire (regenerative types). Total number of individuals (LPs) and total cover (MPs) per plot for each of these groups was compared between grassland plot treatment groups by univariate analysis of variance with randomization testing, and between border plots and grassland plots Raunkiaer’s life forms and sub-types used in this study Main type Sub-type Criteria Therophytes — Geophytes Bulbous geophytes Rhizomateous geophytes Forbs Caespitose graminoids No perennating buds; plants complete life cycle in 1 year; only seeds as perennating structures Bulbs or corms as perennating organs, situated below the soil surface Rhizomes or tubers as perennating organs, situated below the soil surface Forbs with meristems at the soil surface Caespitose graminoids with meristems more or less at the soil surface, usually in densely packed tussocks In general multi-stemmed growth; according to common local denomination of species In general single-stemmed growth; according to common local denomination of species Herbaceous or woody plants without self-supporting structures Hemicryptophytes Shrubs — Trees — Lianas — Modified from Raunkiaer (1934). ARTICLE IN PRESS G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 taken as a group (Euclidean distance; a ¼ 0:05). Spearman rank correlations were calculated between total number (LPs and MPs) or total cover (MPs only) of woody individuals and the variables describing vegetation structure for all grassland plots to test if the woody species component in the grassland was related to structural factors of the community, such as density of the herbaceous layer. For this, data from the survey right before (unburned plots) and right after the burns (burned plots) and from the survey conducted 2–3 months after the burns were used. Results Raunkiaer’s life form and fire life form spectra for the community: data from SPs When comparing relative cover of the different life forms in the treatment groups (grassland plots with different time since fire), few significant differences could be found for any of the life form categories. Over all treatment groups, hemicryptophytes amounted to 67.3% of relative cover (caespitose grasses alone to 50.1%), geophytes to 16.3% and shrubs to 15.1% (mean values). Therophytes barely contributed to total cover (Table 2A). Trees and lianas showed low cover values. In border plots, relative cover of caespitose grasses was significantly lower compared to grassland plots as a group, in contrast to trees and lianas for which the opposite was true. Cover of trees, but not shrubs, was significantly higher at the border. Concerning number of species in each life form group, hemicryptophytic forbs were the most important, followed by caespitose grasses, shrubs and rhizomateous geophytes, with little differences between treatment Table 2. 31 groups (Table 2B). Species numbers for the different life-form groups did not differ much at the forest border, except for liana and tree species. Therophytes were almost completely absent. Standing dead biomass differed significantly between the three treatment groups (po0:001), with mean values of 2.5% in recently burned SPs (group1), 9.8% in SPs of group 2 and 23.2% in SPs of group 3. Standing dead biomass almost completely could be contributed to species from the Poaceae or Cyperaceae. In the border plots (all unburned since 3 years or more), standing dead biomass had a mean cover of 10.4%. In the fire life form classification, sprouting species summed up to 55.5% of relative cover in recently burned plots (Table 3). Their contribution, however, was markedly lower in plots of group 2, and relative cover of hemicryptophytic sprouters differed significantly between groups 1 and 3. While cover of sprouting forbs and shrubs thus decreased with time since fire, relative cover of caespitose grasses, exclusively making up the group of resisters in grassland plots, showed an increase with time since fire. Non-sprouting species contributed less than 10% of relative cover in all groups of grassland plots. Border plots had significantly higher relative cover of non-sprouting trees, sprouting trees and lianas, and significantly less of caespitose grasses, which contributed to less than 1/3 of relative cover at the forest border. Characterization of the woody stratum: data from MPs and LPs Cover values for shrub and tree species was higher in MPs than in SPs, most likely due to the very small total area size sampled by SPs. This under-representation of shrubs and trees in the SPs has to be kept in mind when Vegetation (A) and floristic (B) spectrum of Raunkiaer’s life forms (n ¼ 12 for grassland groups and border plots) Therophytes Geophytes* Bulbous Rhizomateous Hemicryptophytes Caespitose graminoids Forbs Shrubs Trees Lianas A: Relative cover values (vegetation spectrum) B: Percentage of species (floristic spectrum) Group 1 Group 2 Group 3 Border Group 1 Group 2 Group 3 Border 0.2% 19.6% a 0.7% 18.9% 62.1% 42.0% 20.1% 15.7% 2.1% 0.2% 0.0% 12.2% b 0.1% 12.1% 70.2% 51.0% 19.2% 17.2% 0.0% 0.0% 0.1% 17.0% ab 0.3% 16.7% 69.5% 57.2% 12.4% 12.3% 0.2% 0.7% 0.0% 11.9% 0.0% 11.8% 44.3% 31.2% 13.1% 9.8% 7.9% 25.8% 0.9% 19.3% 4.4% 14.9% 58.8% 25.4% 33.3% 17.5% 1.8% 1.8% 0.0% 17.8% 2.5% 15.3% 62.7% 28.0% 34.7% 19.5% 0.0% 0.0% 1.6% 14.8% 3.1% 11.7% 55.5% 23.4% 32.0% 22.7% 2.3% 3.1% 0.0% 14.0% 0.8% 13.1% 50.8% 20.5% 30.3% 16.4% 12.3% 6.6% For the vegetation composition (based on relative cover), plots from group 1 and 2 differed significantly for geophytes (indicated by an asterisk in the table; po0:05; different letters behind numbers indicate significant differences between groups for geophytes). Relative cover of all hemicryptophytes, caespitose grasses, trees and lianas differed between border plots and all grassland plots taken as a group (indiated by italics in the table; po0:001). ARTICLE IN PRESS 32 Table 3. G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Fire life form distribution in frequently burned grassland on Morro Santana, Porto Alegre, RS, Brazil Relative cover values Non-sproutersa Therophytes Hemicryptophytes Shrubs Trees Sprouters (from belowground organs) Geophytes bulbous rhizomateous Hemicryptophytic forbs* Shrubs Trees Lianas Resisters (aboveground survival)b Caespitose graminoids (hemicryptophytic) Shrubs Trees Border Gr. 1 Gr. 2 Gr. 3 2.4% 0.2% 1.3% 0.9% 0.0% 55.5% 19.6% 0.6% 18.9% 18.8% a 14.8% 2.0% 0.2% 42.0% 42.0% 0.0% 0.0% 9.0% 0.0% 6.1% 2.9% 0.0% 39.7% 12.2% 0.1% 12.1% 13.2% ab 14.3% 0.0% 0.0% 51.0% 51.0% 0.0% 0.0% 6.9% 0.8% 1.6% 4.3% 0.2% 36.5% 17.0% 0.3% 16.7% 10.9% b 8.0% 0.0% 0.7% 57.1% 57.1% 0.0% 0.0% 6.5% 0.0% 1.7% 0.7% 4.1% 63.0% 11.9% 0.0% 11.8% 12.6% 9.1% 3.7% 25.7% 31.3% 31.2% 0.0% 0.1% Percentage of species All Campos plots Border plots 7.7% 1.1% 2.2% 2.8% 1.7% 67.9% 17.7% 3.3% 14.4% 30.9% 15.5% 1.1% 2.8% 24.3% 24.3% 0.0% 0.0% 14.5% 0.0% 4.1% 2.5% 8.2% 63.9% 13.9% 0.8% 13.1% 26.2% 13.9% 3.3% 6.6% 21.3% 20.5% 0.0% 0.8% Sprouting hemicryptophytic forbs differed in relative cover value between groups of grassland plots (indicated by an asterisk; different letters behind numbers indicate significant differences between groups for hemicryptophytic forbs). Groups printed in italics differed significantly between grassland plots as a group and border plots concering relative cover value (po0:05). a Per definition, no non-sprouting geophytic species exist. See discussion for classification of caespitose grasses. b No resisting geophytes, hemicryptic forbs or lianas could be found in the study. interpreting the data on the community level and underlines the importance of a nested design when working in communities with distinct herbaceous and woody strata, where high richness of the herbaceaous layer impedes working with larger plot size. Using the MP data, in average, 5.4 individuals of shrubs and 0.1 of trees could be found per m2 in the grassland. In all, 38 of the species (25 shrubs, 13 trees) were sprouters and 21 non-sprouters (9 shrubs and 12 trees). Sprouters showed substantially higher cover values than non-sprouters both in grassland and at the border, however, more pronounced in the grassland and relatively more in recently burned areas. In general, cover of shrubs and trees rose with time since fire (Table 4A). Tree species, border species or forest species were of little overall importance in the grassland’s woody species community, but present throughout the area, whereas grassland shrubs clearly were the most important component of the grassland. The only resisters were Leucothoe eucalyptoides (Ericaceae), Butia capitata (Araceae), both with thick bark, and Opuntia macrocantha (Cactaceae), where at least part of the plant survives due to its high moisture content. In grassland LPs, a mean of 0.23 woody plants higher than 80 cm could be found per m2, 0.21 of these being shrubs and 0.02 trees (Table 4B). Number of woody species was significantly higher (po0:001) in plots of group 3, where 0.48 woody individuals above 80 cm were present per m2, in comparsion to 0.05 and 0.14 in treatment groups 1 and 2, respectively. The largest part of woody species in the grassland were grassland species, in contrast to the border, where species from the forest or from the border were of importance as well, with in general higher numbers of trees and shrubs from all successional groups (Table 4B). No strong correlations (with a correlation coefficient above 0.4 or below 0.4) between number or cover of woody species in LPs and MPs and structure of the herbaceous stratum (cover of dead and live grasses, herbs, lianas, litter, open soil, rocks, height of grass layer) was detected, for either sampling data of vegetation structure attributes. Discussion Applicability of Raunkiaer’s life form system to fire Application of Raunkiaer’s system to tropical ecosystems has been criticized (Sarmiento and Monasterio 1983; Solbrig 1993) because many species cannot readily be classified into the categories, as growth patterns may undergo changes from one class to another, depending on events such as heavy drought and fire. Trees, for example, may resprout like shrubs, recovering their ARTICLE IN PRESS G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 33 Table 4. Cover and number of shrubs and trees per m2, using data from (A) 232 plots of 1.5 m  1.5 m (cover values; all woody species 410 cm) and (B) 84 plots of 4.5 m  4.5 m (number of individuals per m2, all woody species480 cm) on Morro Santana, Porto Alegre, RS, Brazil Total Growth forms Trees Shrubs Successional groups Grassland species Border/pioneer species Forest species Regenerative types Non-sprouters Resprouters Resisters (A) MPs—cover (all individuals410 cm) (B) LPs—number per m2 (all individuals480 cm) (A1) Grassland with different time since fire (Groups 1, 2, 3) (A2) Open grassland (Camp.) and border (Bord.) (B1) Grassland with different time since fire (Groups 1, 2, 3) (B2) Open grassland and border Gr. 1 Gr. 2 Gr. 3 Camp. Bord. Gr. 1 Gr. 2 Gr. 3 Camp. Bord. 20.3% b 29.3% a 35.8% a 28.4% b 45.2% a 0.05 b 0.14 b 0.48 a 0.23 b 0.65 a 1.8% 18.5% b 0.8% 28.5% a 2.9% 32.9% a 1.8% b 26.6% 21.9% a 23.3% 0.02 0.03 b 0.02 0.12 b 0.02 0.46 a 0.02 b 0.21 0.32 a 0.34 18.5% b 0.4% 28.0% a 0.5% 29.6% a 3.9% 25.3% a 1.6% b 14.3% b 10.3% a 0.03 b 0.00 0.12 b 0.00 0.43 a 0.03 0.19 0.01 b 0.21 0.14 a 1.4% 0.8% 2.3% 1.5% b 20.6% a 0.02 0.02 0.02 0.02 b 0.31 a 1.1% c 18.8% b 3.7% b 25.6% a 5.6% b 22.5% 15.1% a 27.4% 0.02 0.03 b 0.00 0.14 a 0.20 a 0.28 a 0.07 b 0.15 b 0.33 a 0.30 a 0.4% 0.0% 12.2% a 23.0% ab 0.6% 0.3% 2.7% 0.00 0.00 0.00 0.00 b 0.03 a Values presented comparing groups of grassland plots with different time since fire (A1, B1) and grassland plots as a group with border plots (A2, B2). Different letters indicate significant differences between groups (po0:05), to be read per line separately for A1, A2, B1, B2. biomass by ‘‘crowns on the ground level’’ (Bellingham and Sparrow 2000). Further, the height limit of 25–50 cm between chamaephytes and phanerophytes (Ellenberg and Mueller-Dombois 1966) is a consequence of the height of temperate clima dwarf shrubs and cannot be applied in tropical or subtropical systems, where chamaephytes may grow higher: here, division into growth forms (shrubs and trees), i.e. a categorization based on plant architecture, seems to be more useful (Sarmiento and Monasterio 1983). The life form system had originally been elaborated to characterize plant strategies in face of an infavorable season, and not as a reaction to disturbances, which shape, for example, tropical savannas or subtropical grasslands. In systems with recurrent disturbances, position of buds is not solely a consequence of climatic conditions, but influenced by other environmental factors, e.g. the action of herbivory or fire (Cain 1950). The life form system therefore is useful for description of vegetation physiognomy, but does not necessarily serve for prediction of climatic conditions, as originally indended by Raunkiaer. Fire life forms In vegetation subject to frequent burns, survival and sprouting ability depend on the degree of bud protection: a chamaephyte or phanerophyte may have to sprout from belowground buds after the fire, or a hemicryptophyte may not be able to sprout at all. Between growth or life forms, traits allowing for survival of fire vary. Resistance in woody plants is principally achieved by protective tissues, e.g. thick bark with low heat conductivity (Bond and Van Wilgen 1996; Gill 1981), often joined by elevation of buds above the flammable vegetation layer (e.g., Givnish et al. 1986). In tussock grasses, densely packed basal leaf sheats allow for protection of aboveground meristems from fire (e.g., Gill 1981; Sarmiento 1992). Sprouting ability from belowground organs is usually a consequence of buds protected by the soil, where temperature effects on plant tissue stay below values causing damage (451–55 1C for most plants; Levitt 1980): higher temperatures are only reached in the uppermost centimeter of soil (e.g., Auld and Bradstock 1996; Bradstock and Auld 1995; Miranda et al. 1993; Silva et al. 1991). In the studied grassland, very few species manage to keep aboveground live biomass through a fire. However, meristems of tussock grasses, making up more than 50% of plant cover 1 year after a burn, remained alive slightly above the soil surface; species from this group thus have to be considered as resisters, even though their behavior does not differ much from hemicryptophytes sprouting from buds at the soil surface. Individuals of Eryngium horridum (Apiaceae), a large rhizomateous rosette species with fibrous leaves and high water content, sometimes did not burn completely and managed to ARTICLE IN PRESS 34 G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 keep some live biomass at the center of the leaf rosettes, however, regaining aboveground biomass after the fire through sprouting of new rosettes (Fidelis et al. submitted), i.e. essentially behaving like a sprouting species. The cactus species O. macrocantha and Pavonia ottonis, sparsely present in the studied grassland, will not burn due to their high water content, but, if fire is intense enough, aboveground biomass will die due to the effect of fire temperature on plant tissue. It is difficult to classify them into the fire life form categories, as resprouting can occur from below- or aboveground organs, depending on fire severity and amount of lignified structures. In a study in subtropical grasslands in Texas, Bunting et al. (1980) showed that 20–65% of plants from three Opuntia species did not sprout after fire, but that mortality rate rose to 60–80% in a period of 4 years after fire, as a consequence of increased herbivory and fungal or bacterial infections on firedamaged plants. Resisting capacity for these species thus is clearly lower than that of the ‘‘true’’ resisters, in our study only the tree L. eucalyptoides (Ericaceae) and the palm B. capitata (Arecaceae). A small percentage of species in the studied grassland was not able to resprout, but depended on regeneration from seeds after the disturbance (obligate seeders; Bond and Van Wilgen 1996). This group of non-sprouters comprised plants from all life forms, except for geophytes. This latter group should be the most successful of the fire life forms considering survival of burns (Taylor 1978), explaining why frequent fires often favour sprouting forbs, often geophytes, over grasses, mostly hemicryptophytes (Daubenmire 1968; Rowe 1983). In hemicryptophytes, the large majority of the species in our grassland plots either were resprouters (53.9% of species) or resisters (only the caespitose grasses, 42.3%). In the group of shrubs, however, 84.9% of species in grassland plots showed the ability to resprout, indicating that position of aboveground buds alone is a poor predictor of fire survival for the studied grassland. Both the application of Raunkiaer’s system and of the fire life form classification showed little overall changes between different treatment groups, reflecting slight shifts in relative importance in different post-fire stages due to differences in competitive ranking (Suding 2001), but no prounced changes in plant types. When classifying plant species into fire life form categories, two things have to be kept in mind: fire intensity may differ between fires and according to local site characteristics, and resistance capacity in respect to fire may not be the same for all life stages of plants (e.g., Bond and Van Wilgen 1996; Gill 1981). These two factors, alone or in combination, in some cases may allow for survival of aboveground biomass in individuals even without protected buds on protected sites (in the study area, for example, between rock outcrops, where no continuous grass layer exists to support a fire) and for damage of even belowground plant parts in others when in an early life-cycle phase or when subjected to extremely severe fire event, e.g. on sites with higher fuel availability (see example of Cactus species above). Sensitivity of sprouting species to fire will further depend on season of fire and thus on specific phenology of plant active phases and carbonhydrate storage (Bond 1997; Chidumayo 2006), requiring to study the phenological cycles of the species in question for a more detailled prediction of the effect of fire on a grassland community (Loucks et al. 1985; Sarmiento and Monasterio 1983; Towne and Owensby 1984). Brief functional characterization of main species groups in relation to fire Non-sprouting species No significant differences could be found for cover values of non-sprouting species, i.e. obligate seeders, between the treatment groups, suggesting that, at least in their majority, they cannot be considered to be fire followers as found in some shrubland or grassland communities (e.g., Ghermandi et al. 2004; Keeley et al. 1981), but will need some time to regain their pre-fire cover values through new seedling recruitment from the seed bank or through seed dispersal (see also Overbeck et al. 2005, 2006b). Fire annuals sensu Keeley et al. (1981) were absent in the studied grassland. Within the group of non-sprouters, a small number of hemicryptophytic species with lack of protected buds was present in all treatment groups. Especially common were Dichondrea sericea and Evolvulus sericeus, two small creeping herbs of similar habitus (Convolvulaceae) that also appeared in great quantities in a study of the seed banks in the grasslands on Morro Santana (Müller and Overbeck, unpubl.). Of great importance considering cover values, especially in treatment groups 2 and 3 with more time since fire, were the shrubs Heterothalamus psiadioides and Baccharis dracunculifolia, which do not resprout, in contrast to a number of other Asteraceae shrub species with very similar habitus. Especially H. alienus showed very strong recruitment in some plots of group 2, where it had been present with large cover values before the last burn (field observation). As this species also was very abundant in the seed bank in the study area (unpubl. data), most probably the creation of open soil by the fire event will have been responsible for its regeneration. In contrast to chaparral (Christensen 1985; Keeley 1986), frequent fires apparently do not eliminate seeders in subtropical grassland. Graminoids Caespitose grasses, in their vast majority tussock grasses with the C4 photosynthetic pathway, together with Cyperaceae species accounted for over 50% of ARTICLE IN PRESS G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 vegetation cover in the studied grassland. We did not found any annual grasses, and only a small percentage of grasses was stoloniferous or rhizomateous, in contrast to grazed grasslands in the region (Boldrini and Eggers 1997; Rodrı́guez et al. 2003). The majority of the caespitose grasses found in the study on Morro Santana also occur in the Brazilian Cerrado, including most of the dominant species (e.g., Andropogon lateralis, Leptochoryphium lanatum, Elyonurus muticus). Tussock grasses present densely packed basal shoots that allow for survival of fire despite aboveground location of meristems (Gill 1981); young plants, however, may be seriously affected by fire in their survival (e.g., Silva and Castro 1989). Some tussock grasses depend on regular burns on the long run: without periodic removal of biomass through fire, shading by dead biomass inhibits survival and tillering and higher humidity under the litter may cause death and decay of underground plant parts within a few years (e.g., Bond et al. 2003; Morgan and Lunt 1999; Silva et al. 1990, 1991; Vogl 1974). Increased photosynthetic activity after fire has been documented for Andropogon gerardii in tallgrass prairie (Knapp 1985), and increased growth rates after burning are known for many caespitose grass species (Silva et al. 1991), e.g. for A. lateralis, one of the most dominant grasses in southern Brazil (Trindade and Da Rocha 2001). Sexual reproduction is stimulated by burning in many savanna grass species (Gill 1981; Sarmiento 1992). Especially grasses from the Andropogoneae tribe, of high importance in the studied grassland, are extremely productive under suitable, i.e. sufficiently humid, climate conditions, producing large amounts of badly decomposing biomass (Bond et al. 2003), thus allowing for yearly burns where dominant (see also Overbeck et al. 2005). Woody plants Woody species in South Brazilian Campos differ strinkingly from woody species both in African and neotropical savanna. In these systems, trees, commonly resisting fire because of protective bark, characterize vegetation physiognomy (Sarmiento and Monasterio 1983 for an overview). Tree species found in grassland communities in southern Brazil, in contrast, are pioneer trees that usually do not tolerate fire; frequent fires thus should impede recruitment of forest pioneer trees in grassland and thus forest expansion (Müller et al. unpubl.). The woody stratum in Campos grassland is comprised principally of grassland shrubs, in their majority sprouters, with species from the Asteraceae having the greatest importance both in terms of species number and cover values. Usually, these shrubs do not exceed 2 m in height, and some of them remain within the height of the grass layer. In the absence of disturbance, the shrubs may form dense stands, often as belts along the forest–grassland border (Oliveira and 35 Pillar 2004). However, it has not been studied so far if and in which ways they facilitate establishment of forest species and to what extent they suppress flammability, thus possibly accelerating vegetation change to forest when fire intervals become longer. In southern Brazil, fires reduce the shrub component more or less to the ground level, with rapid recovery of biomass after the fire. Flowering and fructification for the majority of grassland shrubs (e.g., sprouting Asteraceae) may take place within 3 months after the fire (field obs.), for some species even less (e.g., the resprouter Schinus weinmanniaefolius, Anacardiaceae: fruits two months after fire). Distribution of shrubs in the system is rather patchy; this may be due to differences in recruitment behavior (populations of sprouting species should be spatially more stable), differences in edaphic conditions or different fire history. From field observations and considering the lack of significant correlations between the shrub/tree layer and the herbaceous layer, we conclude that shrub density does not become high enough as to impede growth of caespitose grasses and forbs, at least in fire intervals of less than 5 years. If recruitment of shrub species were facilitated by fire (presence of open soil), an interaction between fire regime (colonization sites) and presence of shrubs in nearby unburned areas (seed sources) could exist. For South Brazilian grasslands, studies adressing functional characteristics, life history strategies and population dynamics of woody species under different disturbance regimes are necessary, especially to be able to compare Campos grassland to Brazilian Cerrado or other savanna systems. Under present climatic conditions and without recurrent disturbances, South Brazilian grasslands will turn into shrublands, or into a mosaic of grassland, shrublands, and forest islands, subsequently leading to forest development (Müller and Forneck 2004; Oliveira and Pillar 2004; Müller et al. 2006). Resprouting forbs High diversity of South Brazilian Campos is largely a consequence to the high number of forb species (see e.g., Overbeck et al. 2006a), in their vast majority sprouters. In other burned grasslands, e.g. North American tallgrass prairie (Benson et al. 2004) or Australian temperate grassland (Morgan 1999), resprouting has been identified to be the prevalent strategy for post-fire biomass recovery in forbs. High productivity of caespitose grasses and accumulation of litter leads to the loss of forbs due to dominance effect of graminoids in an apparently relatively random process of thinning out of herbaceous species irrespective of their habitus (Overbeck et al. 2005). Litter, which will accumulate in the absence of fire, grazing or mowing, in general is considered to reduce forb density and richness in grasslands around the world (e.g., Facelli and Pickett 1991; Knapp and Seastedt 1986). In the studied ARTICLE IN PRESS 36 G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 grassland, richness of (sprouting and non-sprouting) forb species thus can be directly linked to the fire cycle (Leach and Givnish 1996), even though these should not be important in terms of flammability. Studies of population biology and life history of herbaceous species in southern Brazil are missing almost entirely (but see Fidelis et al. submitted). Life-form composition of Brazilian subtropical grassland in a global perspective High importance of shrubs and increased recruitment of forest pioneer species in sites close to the forestborder (seed sources) demonstrates the suitability of the Campos biome’s climate for woody vegetation types; in fact, longer unburned grasslands in southern Brazil resemble secondary succession in areas formerly covered by forests (Reitz and Klein 1964). Similarily to Campos grassland (this study; Boldrini 1993; Garcia et al. 2002; Rodrı́guez et al. 2003) a lack of annual species has also been noted for Brazilian Cerrado, in contrast to many other grasslands and savannas worldwide (Batalha and Martins 2002; Sarmiento and Monasterio 1983). Bond et al. (2003) suggest for subtropical Southern Africa that perennial sprouters are characteristic of fire-dependent grasslands, while annuals prevail in climatically defined grassland, i.e. in regions where development of woody vegetation types is impeded by insufficient moisture supply. Similiarily, in Australian temperate lowland grasslands the forb component is dominated by perennials in all but the driest regions (Lunt and Morgan 2001). Most of the Cerrado biome today is considered to be under climate suitable for forest establishment, but – like in southern Africa – fire, interacting with climatic and edaphic factors, determines actual vegetation physionomy (Henriques and Hey 2002; Oliveira-Filho and Ratter 2002). The same seems to be true for South Brazilian grassland. In the subtropical Campos region, with a humid climate without any dry season, no climatic restriction favors an annual life cycle. On the other hand, in many environments, annual species are known to profit from disturbance events (Belsky 1992; Grime 1977) and, in many fire-prone grasslands, opportunistic post-fire colonizers appear in early post-fire vegetation development (e.g., Laterra et al. 2003; Lunt and Morgan 2001; Ramsay and Oxley 1986). For tallgrass prairie, some studies have shown that contribution of annuals increases with disturbance (fire, grazing) intensity (e.g., Collins 1987; Engle et al. 2000; Gibson et al. 1993), while in other studies, therophytes were almost missing (Towne and Owensby 1984); however, we do not know of any study adressing life form composition on the gradient from tallgrass to shortgrass prairie. In some Australian temperate grasslands, exotic annuals dom- inate the seed bank and the post-fire seedling flora, which has been attributed to the paucity of native annuals (Morgan 1998, 2001) and to long-term grazing that led to a loss of native species in the seed bank (Lunt 1990). Exotic annuals could not be found in the grassland studied by us, despite the low contribution of native annuals. Does the ‘‘niche for annuals’’ exist in southern Brazil? The lack of therophytes in South Brazilian grassland likely needs to be addressed in a comparative study of grasslands systems around the world, under various climatic conditions and under different disturbance regimes. The life form spectrum is a simple, yet meaningful and readily usable classification; however, at present surprisingly little reliable data on life-form spectra for grassland communities can be found in the literature. If joined by regeneration attributes, like in our study, interpretational value of Raunkiaer’s system should be enhanced considerately, allowing for comparative analysis of the influence of climatic factors and disturbance on composition and vegetation dynamics in grasslands in a global perspective. Acknowledgments We would like to thank Sandra Cristina Müller and Valério DePatta Pillar, Departamento de Ecologia, UFRGS, Porto Alegre, RS, Brazil, for the good cooperation in the project and for discussion. Our thanks go to staff at the Departamento de Botânica, UFRGS, for help with identifying plant species. G.O. received a Ph.D. grant by the German National Academic Foundation (Studienstiftung des deutschen Volkes). The project was supported by the DFG and DAAD (Germany) and CAPES (Brazil) in a ProBral-cooperation. Appendix A. Species recorded in 144 plots of 0.25 m2, pooled to 48 plots of 0.75 m2, on Morro Santana, Porto Alegre, RS, Brazil Given are family, species name, life form (LF; modified after Raunkiaer (1934); th: therophyte, gb: bulbous geophyte, gr: rhizomateous geophyte, h: hemicryptophyte (excluding caespitose graminoids), hc: hemicryptophytic caespitose graminoid; s: shrub, t: tree, l: liana) and regenerative type after fire (RT; r: resister, s: sprouter, n: non-sprouter), mean cover value (C) and frequency (F) of species per group of plots, separated for grassland plots at the forest-grassland border (border, n ¼ 12), and plots in the open grassland, grouped into plots burned three months before (Group 1; n ¼ 12), burned a year before (Group 2; n ¼ 12) and unburned for 3 years or more (Group 3, n ¼ 12). No information is given for species not totally identified (Table A1). Table A1 Family Acanthaceae Amaranthaceae Amaryllidaceae Anacardiaceae Apiaceae RT n s s s s s s s s s n s s s s s s s s s s s s s s l gr h h h h h h s h h s h s s n s s s s s s s s s s s s s s s s s s s Group 1 Group 2 Group 3 C F C F C F C F 0.009 0.005 0.021 0 0.028 0.005 0 0.289 0.005 0.009 0.046 0.009 0.141 0 0 0.037 0.023 0 0 0.023 0.002 0 0.002 0 0.002 0 0 0.882 0.014 0.014 0.009 0 0 0 0 0.005 0.014 0 0 0 1 1 4 0 3 1 0 6 1 3 2 1 2 0 0 3 1 0 0 1 1 0 1 0 1 0 0 8 1 2 3 0 0 0 0 1 1 0 0 0 0 0 0.100 0 0.012 0 0 0.037 0.519 0.069 0.009 0 0 0 0.037 0.102 0 0 0 0.171 0.002 0.007 0 0.579 0 0.019 0.019 0 0 0 0.072 0.063 0 0.005 0.005 0 0.056 0 0.014 0.028 0 0 8 0 2 0 0 4 3 7 3 0 0 0 2 7 0 0 0 5 1 1 0 1 0 2 2 0 0 0 7 6 0 1 1 0 3 0 4 2 0 0 0.058 0.007 0.148 0 0.023 0.468 0 0.104 0.049 0 0 0.046 0 0.185 0.005 0 0 0.347 0.002 0.046 0.069 0 0 0.056 0.007 0 0 0.032 0.109 0.005 0.003 0 0.005 0 0.028 0.005 0.183 0 0 0 7 3 2 0 1 8 0 4 5 0 0 5 0 7 1 0 0 9 1 7 1 0 0 2 2 0 0 5 10 1 1 0 1 0 4 1 11 0 0 0 0.049 0.005 0 0.016 0 0.252 0.634 0.039 0.069 0 0 0.016 0.053 0.035 0 0.002 0.009 0.127 0.046 0.005 0.005 0.076 0 0.053 0.037 0 0.002 0.009 0.023 0.009 0 0.005 0 0 0.032 0 0.030 0 0 0 7 1 0 3 0 6 3 5 10 0 0 4 4 5 0 1 1 5 1 2 1 4 0 5 4 0 1 2 3 2 0 1 0 0 5 0 3 0 37 s h gr gb s gr gr gr gr gr h l h h h h Border ARTICLE IN PRESS Justicia brasiliana Roth Stenandrium Nees sp. Pfaffia tuberosa (Moq. ex DC.) Hicken Habranthus gracilifolius Herb. Schinus weinmanniaefolius Engl. Eryngium ciliatum Cham. & Schlecht. Eryngium elegans Cham. & Schlecht. Eryngium horridum Malme Eryngium pristis Cham. & Schlecht. Eryngium sanguisorba Cham. & Schlecht. Hydrocotyle exigua (Urb.) Malme Forsteronia glabrescens Müll.Arg. Rumohra adiantiformis (G.Forst.) Ching Achyrocline satureioides Gard. Acmella bellidioides (Sm.) R.K.Jansen Aspilia montevidensis (Spreng.) Kuntze Asteraceae 1 Asteraceae 2 Baccharis articulata Pers. Baccharis cognata DC. Baccharis dracunculifolia DC. Baccharis leucopappa DC. Baccharis ochracea Spreng. Baccharis patens Baker Baccharis rufescens Spreng. Baccharis sessiliflora Vahl Baccharis trimera (Less.) DC. Calea serrata Less. Calea uniflora Krasch. Chaptalia integerrima (Vell.) Burkart Chaptalia runcinata Kunth Chaptalia sinuata Baker Conyza bonariensis (L.) Cronquist Conyza chilensis Spreng. Eupatorium ascendens Sch.Bip. ex Baker Eupatorium intermedium DC. Eupatorium ivaefolium L. Eupatorium lanigerum Hook. & Arn. Eupatorium ligulaefolium Hook. & Arn. Eupatorium tweedianum Hook. & Arn. LF G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Apocynaceae Aspidiaceae Asteraceae Species Family Asteraceae Cyperaceae Heterothalamus psiadioides Less. Hieracium commersonii Monnier Hypochoeris sp. Lucilia acutifolia Cass. Lucilia nitens Less. Noticastrum gnaphalioides (Baker) Cuatrec. Orthopappus angustifolius Gleason Porophyllum lanceolatum DC. Pterocaulon alopecuroideum DC. Pterocaulon rugosum Malme Senecio heterotrichius DC. Stenachaenium riedelii Baker Stevia aristata D.Don ex Hook. & Arn. Stevia cinerascens Sch.Bip. ex Baker Verbesina subcordata DC. Vernonia flexuosa Sims Vernonia nudiflora Less. Viguiera anchusaefolia (DC.) Bak. Dolichandra cynanchoides Cham Macfadyena unguis-cati (L.) A.H.Gentry Moritzia ciliata DC. Dyckia leptostachya Baker Parodia ottonis (Lehm.) N.P.Taylor Wahlenbergia linarioides DC. Spergularia grandis Cambess. Halimium brasiliense Gross. Commelina erecta L. Convolvulus crenatus Vahl Dichondra sericea Sw. Evolvulus sericeus Sw. Ipomoea nitida Griseb. Bulbostylis sp. Bulbostylis closii Barros Bulbostylis juncoides (Vahl) Kük. ex Osten Bulbostylis sphaerocephalus C.B.Clarke Carex phalaroides Kunth Cyperaceae 1 Cyperus aggregatus Endl. Cyperus incomtus Kunth Cyperus lanceolatus Poir. LF s gr h gr gr h h s h h s gr h h h h s h l l h gr s th h h h l h h gr hc hc hc hc gr gr gr gr gr RT n s s s s s s s s s n s s s s s s s s s s s s n n s s s n n s r r r r s s s s s Border Group 1 Group 2 Group 3 C F C F C F C F 0 0 0 0 0 0 0.009 0.007 0.009 0 0 0 0.016 0.005 0.032 0.014 0.023 0 0.009 0.002 0.005 0 0 0 0.002 0 0.035 0.005 0.005 0.030 0.009 0 0 0.007 0.023 0 0 0 0.005 0 0 0 0 0 0 0 1 2 1 0 0 0 1 1 2 3 6 0 1 1 1 0 0 0 1 0 5 1 1 7 1 0 0 1 1 0 0 0 1 0 0 0 0 0.021 0.009 0 0.005 0.044 0.019 0.067 0 0.014 0.009 0.035 0.028 0.162 0.093 0 0 0 0 0.139 0.028 0 0 0.005 0.002 0 0.012 0.056 0 0.012 0.007 0.046 0.007 0 0 0.002 0 0 0 0 0 5 1 0 1 8 1 5 0 1 1 4 2 9 6 0 0 0 0 1 1 0 0 1 1 0 3 8 0 2 2 9 1 0 0 1 0 0 0.113 0.032 0 0.081 0.009 0.012 0.102 0.026 0 0.081 0.014 0.009 0.002 0.102 0 0.065 0.109 0.019 0 0 0 0 0 0 0 0.012 0.012 0 0.009 0.049 0 0.009 0.012 0.009 0.030 0 0.005 0.016 0 0.007 10 4 0 11 2 2 8 5 0 4 3 1 1 2 0 6 9 2 0 0 0 0 0 0 0 3 2 0 2 7 0 2 2 1 1 0 1 4 0 2 0.188 0 0.009 0.021 0.023 0.019 0.007 0.021 0 0.069 0.012 0 0.005 0.030 0.002 0.132 0.116 0 0 0 0 0 0 0.002 0 0.009 0.007 0.023 0.019 0.032 0 0 0 0.016 0.007 0.007 0 0 0 0 2 0 1 4 2 1 2 7 0 7 2 0 1 5 1 9 10 0 0 0 0 0 0 1 0 2 2 1 3 8 0 0 0 5 2 2 0 0 0 0 ARTICLE IN PRESS Boragniaceae Bromeliaceae Cactaceae Campanulaceae Caryophylaceae Cistaceae Commelinaceae Convolvulaceae Species G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Bignoniaceae 38 Table A1. (continued ) Cyperaceae Dioscoreaceae Ebenaceae Ericaceae Erythroxylaceae Euphorbiaceae Euphorbiaceae Lamiaceae Liliaceae Linaceae Lythraceae Malpighiaceae Malvaceae t h h h s gr s h s h h gr gr h s h gr h gb gb h h h s h h gb h h l s s s n s s s s s s s s s s s s s s s s s s s s s s s s n s s s s s s s 0.023 0 0.009 0 0.120 0.002 0.005 0.009 0.037 0 0.012 0 0 0.002 0 0 0.009 0 0.007 0.002 0 0.021 0 0.007 0 0.014 0.009 0 0.005 0.009 0 0 0 0.002 0 0.002 0.005 0 0.012 0.002 0 0 0 0.009 0.014 0.009 4 0 3 0 4 1 1 1 3 0 2 0 0 1 0 0 1 0 1 1 0 4 0 1 0 3 2 0 1 2 0 0 0 1 0 1 1 0 1 1 0 0 0 1 2 1 0.192 0.016 0.025 0 0 0 0 0 0.049 0.005 0.019 0 0.002 0 0.005 0.002 0.049 0 0.028 0 0.009 0.039 0.014 0.039 0.005 0.009 0 0.007 0.009 0.016 0 0.005 0.012 0.005 0.002 0 0.012 0.009 0 0 0 0.005 0.005 0 0 0 12 4 5 0 0 0 0 0 6 1 4 0 1 0 1 1 3 0 4 0 1 5 1 2 2 4 0 1 2 3 0 2 2 2 1 0 1 1 0 0 0 1 1 0 0 0 0.079 0.007 0.030 0.009 0 0 0 0 0.139 0.005 0.042 0 0 0 0 0.028 0 0.042 0.009 0.079 0.005 0.053 0 0 0 0.039 0.021 0 0 0.012 0.009 0.005 0 0.028 0.007 0.046 0.060 0 0.630 0 0 0.002 0 0 0.023 0.010 11 3 6 1 0 0 0 0 7 1 7 0 0 0 0 4 0 2 1 1 1 8 0 0 0 4 4 0 0 2 2 1 0 3 2 5 4 0 4 0 0 1 0 0 3 1 0.116 0 0.009 0 0 0.002 0 0.005 0.074 0.032 0.014 0.005 0 0 0 0.012 0.023 0.005 0.039 0 0.005 0.021 0 0.009 0 0.007 0.039 0 0.014 0 0 0.002 0 0.009 0.002 0 0.002 0 0 0 0.005 0 0 0.009 0.002 0.005 10 0 3 0 0 1 0 1 7 2 5 1 0 0 0 3 3 1 7 0 2 5 0 1 0 1 5 0 2 0 0 1 0 1 1 0 1 0 0 0 1 0 0 1 1 1 39 r r s s s n r n n n s ARTICLE IN PRESS Iridaceae hc hc gr gr l t t t s s h G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Fabaceae Rhynchospora globularis Small Rhynchospora setigera Boeck Scleria sellowiana Kunth Scleria sp. Dioscorea multiflora Mart. ex Griseb. Diospyros inconstans Jacq. Leucothoe eucalyptoides DC. Erythroxylum argentinum O.E. Schulz Croton cf. nitrariaefolium Baill. Croton thermarum Müll.Arg. Euphorbia selloi (Klotzsch & Garcke) Boiss. in DC. Euphorbiaceae 1 Euphrobiaceae 2 Sebastiania brasiliensis Spreng. Tragia emrichii Herter Aeschynomene elegans Cham. & Schlecht. Centrosema virginianum Benth. Chamaecrista nictitans Moench Clitoria nana Benth. Collaea stenophylla Benth. Crotalaria tweediana Benth. Desmanthus tatuhyensis Hoehne Desmodium affine Schltdl. Desmodium incanum DC. Galactia gracillima Benth. Galactia marginalis Benth. Macroptilium prostratum Urb. Mimosa parvipinna Benth. in Hook Rhynchosia diversifolia Micheli Stylosanthes montevidensis Vogel Zornia sericea Moric. Cypella coelestis (Lehm.) Diels Herbertia pulchella Sweet Sisyrinchium macrocephalum Graham Sisyrinchium scariosum I.M.Johnst. Sisyrinchium vaginatum Spreng. Glechon squarrosa Benth. Hyptis stricta Benth. Salvia procurrens Benth. Nothoscordum bonariense Beauverd Cliococca selaginoides (Lam.) C.M.Rogers & Mild. Cuphea glutinosa Cham. & Schlecht. Janusia cf. guaranitica A.Juss. Krapovickasia urticifolia (A. St.-Hil.) Fryxell Pavonia hastata Cav. Sida rhombifolia L. Family Malvaceae Melastomataceae Myrsinaceae Myrtaceae Myrtaceae Orchidaceae Oxalidaceae Species s s t t t s t gb gb gb h hc hc hc hc hc hc hc hc hc hc gr hc gr hc hc hc hc gr hc hc gr hc hc hc gr hc gr hc hc RT s s n n n s s s s s s r r r r r r r r r r s r s r r r r s r r s r r r s r s r r Border Group 1 Group 2 Group 3 C F C F C F C F 0.021 0.032 0.046 0.009 0.046 0 0.093 0 0 0 0.095 0.093 0 0 0 0 0 0.002 0.039 0.046 0 0 0.037 0 0 0 0 0 0.083 0.019 0.009 0.150 0.588 0 0.171 0.000 0.051 0.049 0.005 0.014 3 2 2 1 1 0 1 0 0 0 3 6 0 0 0 0 0 1 4 4 0 0 2 0 0 0 0 0 5 2 1 8 8 0 3 0 4 3 1 1 0.019 0.037 0 0 0 0 0.056 0.005 0.009 0.016 0 0.218 0.044 0.146 0 0 0 0 0.590 0.199 0.005 0.127 0 0.056 0 0 0 0 0 0.014 0 0.044 0.287 0.032 0.296 0 0 0 0.000 0.000 2 6 0 0 0 0 1 1 1 3 0 4 4 7 0 0 0 0 11 7 2 6 0 1 0 0 0 0 0 2 0 6 5 4 4 0 0 0 0 0 0 0.155 0 0 0 0 0 0 0 0.002 0 0.123 0 0.113 0 0.407 0.014 0.350 0.257 0.676 0 0 0.468 0.102 0 0.010 0.019 0.014 0 0.026 0.010 0.174 0.454 0 0.528 0 0 0 0 0 0 5 0 0 0 0 0 0 0 1 0 3 0 4 0 5 2 7 5 9 0 0 6 3 0 3 2 3 0 2 1 8 8 0 5 0 0 0 0 0 0.058 0.012 0 0.009 0 0.009 0 0 0.007 0.009 0 0.551 0.326 0.000 0.053 0.069 0 0.016 0.556 0.188 0 0 0 0.359 0.005 0.005 0.014 0.030 0.000 0.171 0.000 0.025 1.116 0.019 0.044 0.005 0 0 0.005 0 4 4 0 2 0 1 0 0 3 3 0 5 5 0 2 1 0 2 5 5 0 0 0 8 1 1 4 3 0 6 0 6 9 2 3 1 0 0 2 0 ARTICLE IN PRESS Wissadula glechomatifolia R.E.Fr. Tibouchina gracilis (Bonpl.) Cogn. Myrsine coriacea R.Br Myrsine umbellata Mart. Blepharocalyx salicifolius O.Berg Campomanesia aurea O.Berg Myrcia palustris DC. Stenorrhynchus arechavaletsmii Barb.Rodr. Oxalis brasiliensis Lodd. Oxalis conorrhiza Jacq. Peperomia pereskiaefolia H.B.& K. Andropogon lateralis Nees Andropogon leucostachyus H. B. & K. Andropogon selloanus (Hack.) Hack. Andropogon ternatus Nees Aristida circinalis Lindm. Aristida condylifolia Caro Aristida filifolia (Arechav.) Herter Aristida flaccida Trin. & Rupr. Aristida laevis Kunth Aristida venustula Arechav. Axonopus argentinus Parodi Axonopus suffultus (Mikan ex Trin.) Parodi Axponopus sp. Briza calotheca (Trin.) Hack Briza sp. Briza subaristata Lam. Briza uniolae Nees ex Steud. Calamagrostis viridiflavescens Steud. Danthonia montevidensis Hackel & Arech. Danthonia secundiflora J.Presl & C.Presl Dichanthelium sabulorum (Lam.) Gould & C.A.Clark Elionurus muticus (Spreng.) Kuntze Eragrostis polytricha Nees Leptocoryphium lanatum Nees Melica brasiliana Ard. Oplismenus hirtellus (L.) P.Beauv. Panicum ovuliferum Trin. Panicum peladoense Henrard Paspalum mandiocanum Trin. LF G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Piperaceae Poaceae 40 Table A1. (continued ) Poaceae Scrophulariaceae hc hc hc hc s h h h l h h h t s h h h h t t s th h l s r r r r s s s s s s s s n s s s s s n n s n s s s 0.118 0.037 0.016 0 0.046 0.030 0 0.086 0.007 0.102 0 0.019 0.093 0.037 0 0 0 0 0.002 0 0 0 0 0 0 0.241 0.009 0.044 0 0.009 0 0.023 0.007 0.023 0.007 0.009 0.005 0 0 0.002 0.028 0 0 0 0 0.069 4 2 3 0 1 2 0 4 1 1 0 2 1 2 0 0 0 0 1 0 0 0 0 0 0 4 1 3 0 1 0 2 2 1 2 3 2 0 0 1 3 0 0 0 0 1 0.014 0 0.023 0.005 0.093 0 0.005 0.044 0.023 0.012 0 0 0.039 0.002 0.067 0 0 0.005 0.009 0 0.005 0 0 0.005 0.005 0 0 0.093 0 0 0 0 0 0 0 0.002 0.102 0 0 0 0 0 0.012 0 0.002 0 2 0 4 1 1 0 1 3 4 2 0 0 3 1 3 0 0 1 1 0 1 0 0 1 1 0 0 6 0 0 0 0 0 0 0 1 6 0 0 0 0 0 3 0 1 0 0.060 0 0.035 0 0.046 0.044 0 0.713 0.104 0.331 0.009 0.012 0.116 0.009 0.009 0 0 0 0 0.012 0 0 0 0 0 0.030 0.039 0.012 0 0 0.032 0 0.019 0 0 0.076 0.039 0 0 0 0 0 0 0.005 0 0 3 0 3 0 2 4 0 5 8 6 1 2 1 1 1 0 0 0 0 1 0 0 0 0 0 4 4 2 0 0 5 0 5 0 0 10 5 0 0 0 0 0 0 1 0 0 0.012 0 0.227 0 0 0.234 0.005 0.030 0 0.005 0 0.093 0.106 0.007 0.593 0.002 0.002 0 0 0 0 0 0.002 0 0 0.025 0 0.063 0.014 0.016 0 0 0.009 0 0 0.007 0.063 0.005 0.002 0 0 0.019 0.002 0 0.009 0 4 0 8 0 0 6 1 5 0 1 0 5 2 2 5 1 1 0 0 0 0 0 1 0 0 2 0 7 2 3 0 0 3 0 0 3 7 1 1 0 0 1 1 0 1 0 41 Smilacaceae Solanaceae r s r r r r r r r r r r r r r ARTICLE IN PRESS Sapindaceae hc gr hc hc hc hc hc hc hc hc hc hc hc hc hc G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Polygalaceea Rubiaceae Paspalum plicatulum Michx. Paspalum sp. Piptochaetium montevidense (Spreng.) Parodi Poaceae/trib. Andropogoneae 5 Saccharum asperum Steud. Schizachyrium microstachyum (Ham.) Roseng., B.R.Arill. & Izag. Schizachyrium spicatum (Spreng.) Herter Schizachyrium tenerum Nees Setaria parviflora (Poiret) M.Kerguélen Setaria vaginata Spreng. Sporobolus multinodis Hackel Stipa filiculmis Delile Stipa filifolia Nees Stipa tenuiculmis Hackel Trachypogon montufari Nees Poaceae 1 Poaceae 2 Poaceae 3 Poaceae 4 Poaceae 5 Poaceae 6 Poaceae/trib. Andropogoneae 1 Poaceae/trib. Andropogoneae 2 Poaceae/trib. Andropogoneae 3 Poaceae/trib. Andropogoneae 4 Monnina oblongifolia Arechav. Borreria capitata DC. Borreria fastigiata K.Schum. Borreria verticillata G.Mey. Chiococca alba Hitchc. Diodia apiculata K.Schum. Diodia cymosa Cham. Galium uruguayense Bacigalupo Guettarda uruguensis Cham. & Schlecht. Psychotria carthagenensis Jacq. Relbunium hirtum K.Schum. Richardia grandiflora Steud. Richardia humistrata Steud. Rubiaceae sp. Cupania vernalis Cambess. Dodonaea viscosa Jacq. Angelonia integerrima Spreng. Gerardia communis Cham. & Schlecht. Mecardonia herniarioides (Cham.) Pennell Smilax campestris Griseb. Cestrum strigillatum Ruiz & Pav. Family Solanaceae Sterculariaceae Styracacae Symplocaceae Turneraceae Verbenaceae Species h h s t t t s s h h h h l RT s s s n s s s s s s s s s Border Group 1 Group 2 Group 3 C F C F C F C F 0 0 0 0.009 0.116 0.002 0 0 0.002 0.007 0.002 0.012 0.236 0.002 0 0 0 0 0 0 0 0 0 1 1 1 0 0 1 1 1 2 4 1 0 0 0 0 0 0 0 0.002 0.009 0 0 0.009 0.009 0 0 0.030 0 0.007 0 0 0 0 0 0 0 0 0 1 1 0 0 1 2 0 0 3 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.009 0 0.005 0 0.007 0.007 0 0 0.002 0 0 0 0 0 0 0 0 0 0 0 2 0 1 0 3 1 0 0 1 0 0 0 0 0 0.016 0 0.012 0 0 0 0.002 0.009 0 0.060 0.002 0 0.002 0 0 0.002 0.002 0.002 0.002 0.002 3 0 3 0 0 0 1 1 0 3 1 0 1 0 0 1 1 1 1 1 ARTICLE IN PRESS Petunia integrifolia (Hook.) Schinz & Thell. Petunia ovalifolia Miers Waltheria douradinha A. St.Hil. Styrax leprosum Hook. et Arn. Symplocos tetandra Mart. Symplocos uniflora Benth. Turnera selloi Arechav. Turnera sidoides L. Glandularia megapotamica (Spreng.) Cabrera & Dawson Lantana montevidensis (Spreng.) Briq. Verbena ephedroides Cham. Verbena pseudojuncea Gay Cissus striata Ruı́z & Pav. Sp. 1 Sp. 2 Sp. 3 Sp. 4 Sp. 5 Sp. 6 Sp. 7 LF G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Vitaceae Unidentified 42 Table A1. (continued ) Table B1 Family Anacardiaceae Arecaceae Asteraceae Fabaceae Lamiaceae Lauraceae Malvaceae f c c b c c c c c c c c c c c c c c c c c b f f b f c c f f b c c c f c c f f f GF t s t s s s s s s s s s s s s s s s s s s s t t t t s s t t s s s s t s s t s t Border Group 1 Group 2 Group 3 C F C F C F C F 0 0.67 0.83 0 0 1.94 0 0 0 0.28 0 0.72 0 0.94 0.78 0.28 0.28 0.56 0.92 0.28 1.44 0 0 0 0 0.11 2.44 0.39 0 0 0 0 0 0.22 0 0.5 0.22 0 0 0 0 6 2 0 0 4 0 0 0 1 0 5 0 3 3 1 1 1 6 1 13 0 0 0 0 1 11 2 0 0 0 0 0 2 0 3 2 0 0 0 0 0.33 0 0 0.33 5.69 0 0 0.24 0.69 0 1.43 0.25 0.25 2.21 0 0.47 0.19 0.85 0.25 3.71 0 0 0 0 0 0.43 0.42 0 0 0 0 0.47 0 0 0 0 0 0 0 0 6 0 0 3 36 0 0 5 1 0 17 6 3 26 0 3 2 19 3 54 0 0 0 0 0 10 9 0 0 0 0 3 0 0 0 0 0 0 0 0 2.53 0 0 0.53 8.07 0 0.19 0.69 0.06 0 0.51 0.29 0.06 3.19 0 0 0.63 2.68 0 4.56 0 0 0 0 0 2.75 0 0 0 0 0 0 0 0 1.01 0.06 0 0 0 0 18 0 0 4 53 0 2 4 1 0 7 6 1 32 0 0 9 37 0 63 0 0 0 0 0 35 0 0 0 0 0 0 0 0 13 1 0 0 0 0 0.07 0.06 0 1.44 3.85 0.97 0 0.88 2.72 0.06 1.85 0.64 0.97 2.6 0 0.19 3.97 0.74 0 3.26 0 0 0 0 0 3.1 0.72 0 0 0 0 1.25 0 0 0.11 0 0 0 0 0 2 1 0 12 30 7 0 7 13 1 28 10 4 30 0 2 16 14 0 48 0 0 0 0 0 31 7 0 0 0 0 7 0 0 2 0 0 0 0 43 Meliaceae Monimiaceae Myrsinaceae s s r s s s n s s s s s s s s n s n s s s r/s s n r n n n n s s s s s n s s n n n SG ARTICLE IN PRESS Euphorbiaceae Lithraea brasiliensis Marchand Schinus weinmanniaefolius Engl. Butia capitata Becc. Baccharidastrum triplinervium (Less.) Cab. Baccharis articulata Pers. Baccharis cognata DC. Baccharis dracunculifolia DC. Baccharis leucopappa DC. Baccharis ochracea Spreng. Baccharis patens Baker Baccharis rufescens Spreng Baccharis sessiliflora Vahl Baccharis trimera (Less.) DC. Eupatorium intermedium DC. Eupatorium ligulaefolium Hook. & Arn. Eupatorium pedunculosum Hook. & Arn. Eupatorium tweedianum Hook. & Arn. Heterothalamus psiadioides Less. Porophyllum lanceolatum DC. Verbesina subcordata DC. Vernonia nudiflora Less. Opuntia monacantha Haw. Maytenus cassineformis Reiss. Diospyros inconstans Jacq. Leucothoe eucalyptoides DC. Erythroxylum argentinum O.E. Schulz Croton cf. nitrariaefolium Baill. Croton thermarum Müll.Arg. Sebastiania brasiliensis Spreng. Sebastiania serrata Müll.Arg. Calliandra tweedii Benth. Collaea stenophylla Benth. Mimosa parvipinna Benth. in Hook Hyptis mirabilis Briq. Ocotea puberula (Rich.) Nees Pavonia hastata Cav. Sida rhombifolia L. – Trichilia clausseni C.DC. Mollinedia elegans Tul. Myrsine coriacea (Sw.) R.Br. RT G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Cactaceae Celastraceae Ebenaceae Ericaceae Erythroxlaceae Euphorbiaceae Species 44 Table B1. (continued ) Family Species RT SG GF Border C Myrsinaceae Myrtaceae Myrtaceae Solanaceae Styracaceae f c f f f c f f f f f f f b f b f f f t s t t t s t t t s s t t s t s t t t 0 0.39 0 0 0 0.11 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 C 0 0.21 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 F 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C 0 0.22 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Group 3 F 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C 0 0.13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 F 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ARTICLE IN PRESS Rutaceae Sapindaceae n s s s s s n n n s n s n n s s n s s F Group 2 G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Nyctaginaceae Rosaceae Rubiaceae Myrsine umbellata Mart. Campomanesia aurea O.Berg Eugenia hyemalis Camb. Myrcia palustris DC. Myrciaria cuspidata O.Berg Psidium L. Guapira opposita (Vell.) Reitz Quillaja brasiliensis Mart. Guettarda uruguensis Cham. & Schltdl. Psychotria carthagenensis Jacq. Psychotria leiocarpa Cham. & Schltdl. Zanthoxylum rhoifolium Lam. Cupania vernalis Cambess. Dodonaea viscosa Jacq. Matayba elaeagnoides Radlk. Cestrum strigilatum Ruı́z & Pav. Styrax leprosum Hook. et Arn. Symplocos tetrandra Mart. Symplocos uniflora Bedd. Group 1 ARTICLE IN PRESS G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 45 Table C1 Familiy Species RT SG GF Border Group 1 Group 2 Group 3 Anacardiaceae Lithraea brasiliensis Marchand Schinus weinmanniaefolius Engl. Butia capitata Becc. Baccharidastrum triplinervium (Less.) Cab. Baccharis articulata Pers. Baccharis cognata DC. Baccharis dracunculifolia DC. Baccharis leucopappa DC. Baccharis ochracea Spreng. Baccharis patens Baker Eupatorium intermedium DC. Eupatorium ligulaefolium Hook. & Arn. Eupatorium pedunculosum Hook. & Arn. Eupatorium tweedianum Hook. & Arn. Heterothalamus psiadioides Less. Porophyllum lanceolatum DC. Vernonia nudiflora Less. Opuntia monacantha Haw. Maytenus cassineformis Reiss. Diospyros inconstans Jacq. Leucothoe eucalyptoides DC. Erythroxylum argentinum O.E. Schulz Croton cf. nitrariaefolium Baill. Croton thermarum Müll.Arg. Sebastiania brasiliensis Spreng. Sebastiania serrata Müll.Arg. Calliandra tweedii Benth. Collaea stenophylla Benth. Mimosa parvipinna Benth. in Hook Hyptis mirabilis Briq. Pavonia hastata Cav. Trichilia clausseni C.DC. Myrsine coriacea (Sw.) R.Br. Myrsine guianensis (Aubl.) Kuntze Myrsine umbellata Mart. Campomanesia aurea O.Berg Eugenia dimorpha Berg Eugenia uniflora L. Myrcia palustris DC. Myrciaria cuspidata O.Berg Guapira opposita (Vell.) Reitz Guettarda uruguensis Cham. & Schltdl. Psychotria carthagenensis Jacq. Zanthoxylum rhoifolium Lam. Casearia decandra Jacq. Cupania vernalis Cambess. Dodonaea viscosa Jacq. Matayba elaeagnoides Radlk. Cestrum strigilatum Ruı́z & Pav. Styrax leprosum Hook. et Arn. Symplocos tetrandra Mart. Symplocos uniflora Bedd. Lantana camara L. s s r s s s n s s s s s n s n s s r/s s n r n n n n s s s s s s n n n n s s n s s n n s s n n n s s n s s r f c c b c c c c c c c c c c c c c b f f b f c c f f b c c c c f f f f c b f f f f f f f f f b f b f f f b t s t s s s s s s s s s s s s s s s t t t t s s t t s s s s s t t t t s t t t t t t s t t t s t s t t t s 0.25 0.17 0.25 0 0 0.08 0.08 0 0 0.08 1.00 0.50 0.42 0 0.17 0.17 0 0.17 0 0.08 0.25 0.17 0 0 0.25 0.17 0.17 0 0.25 0.17 0.33 0.17 0.50 0.17 0.58 0.42 0 0.08 0.33 1.00 0.08 0.08 0.33 0.08 0.25 0.08 1.92 0.17 0.08 0.17 0.17 0.92 0.17 0.08 0 0 0 0 0 0 0 0 0.33 0 0 0 0 0.25 0 0 0 0.04 0 0 0 0 0 0 0 0 0 0.04 0 0 0 0 0 0 0 0 0 0.13 0.08 0 0 0 0 0 0 0.04 0 0 0 0 0.08 0 0.13 0.13 0 0 0 0.33 0 0 0.13 0 0 0.54 0 0 0 1.13 0.04 0 0 0 0 0 0 0 0 0 0 0.08 0 0 0.13 0.00 0 0 0 0 0 0 0 0.04 0 0.04 0 0 0 0 0 0.08 0.04 0 0 0.08 0 0.13 0.13 0 0 0.46 1.13 0.83 0.04 0.17 1.33 0.21 2.13 0 0.04 2.29 1.33 0.08 0 0 0 0 0 0.17 0.04 0 0 0 0.08 0.58 0 0.13 0 0 0.04 0 0 0.04 0 0.13 0.17 0 0.04 0 0 0 0 0.08 0.08 0.04 0 0 0.13 0 Arecaceae Asteraceae Asteraceae Cactaceae Celastraceae Ebenaceae Ericaceae Erythroxlaceae Euphorbiaceae Euphorbiaceae Fabaceae Lamiaceae Malvaceae Meliaceae Myrsinaceae Myrtaceae Nyctaginaceae Rubiaceae Rutaceae Salicaceae Sapindaceae Solanaceae Styracaceae Verbenaceae ARTICLE IN PRESS 46 G.E. Overbeck, J. Pfadenhauer / Flora 202 (2007) 27–49 Appendix B. Woody species 410 cm, recorded in 252 MPs (1.5 m  1.5 m) on Morro Santana, Porto Alegre, RS, Brazil Given are family, species, regenerative type (RT; r: resister, s: sprouter, n: non-sprouter), successional group (SG, c: grassland species, b: forest pioneer/border species; f: forest species), growth form (GF; s: shrub, t: tree) mean cover per plot (C) and frequency (F) per group of plots, separated for grassland plots at the forest–grassland border (Bord., n ¼ 36) and plots in the open grassland, grouped into plots burned three months before (Group 1; n ¼ 72), burned a year before (Group 2; n ¼ 72) and unburned for 3 years or more (Group 3, n ¼ 72) (Table B1). Appendix C. Woody species 480 cm, recorded in 84 LPs (4.5 m  4.5 m) on Morro Santana, Porto Alegre, RS, Brazil Given are family, species, regenerative type (RT; r: resister, s: sprouter, n: non-sprouter), successional group (SG, c: grassland species, b: forest pioneer/border species; f: forest species), growth form (GF; s: shrub, t: tree) and mean number of individuals per plot, separated for grassland plots at the forest–grassland border (Bord., n ¼ 12) and plots in the open grassland, grouped into plots burned three months before (Group 1; n ¼ 24), burned a year before (Group 2; n ¼ 24) and unburned for 3 years or more (Group 3, n ¼ 24) (Table C1). References Auld, T.A., Bradstock, R.A., 1996. Soil temperatures after the passage of a fire: do they influence the germination of buried seeds? Austral. J. Ecol. 21, 106–109. Batalha, M.A., Martins, F.R., 2002. Life form spectra of Brazilian Cerrado sites. Flora 197, 452–460. Behling, H., 2002. 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(Eds.), Plant Functional Types: their Relevance to Ecosystem Properties and Global Change. Cambridge University Press, Cambridge, pp. 174–194. Bond, W.J., Midgley, G.F., 2000. A proposed CO2-controlled mechanism of woody plant invasion in grasslands and savannas. Global Change Biol. 6, 865–869. Bond, W.J., Van Wilgen, B.W., 1996. Fire and Plants. Chapman & Hall, London. Bond, W.J., Midgley, G.F., Woodward, F.I., 2003. What controls South African vegetation-climate or fire? S. Afr. J. Bot. 69, 1–13. Box, E.O., 1986. Some climatic relationships of the vegetation of Argentina, in global perspective. Veröff. Geobot. Inst. ETH, Stiftung Rübel 91, 181–216. Bradstock, R.A., Auld, T.A., 1995. Soil temperatures during experimental bushfires in relation to fire intensity: consequences for legume germination and fire management in south-eastern Australia. J. Appl. Ecol. 31, 76–84. Bunting, S.C., Wright, H.A., Neuenschwander, L.F., 1980. 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