RESUMO
Biodiversity can buffer ecosystem functioning against extreme climatic events, but few experiments have explicitly tested this. Here, we present the first multisite biodiversity × drought manipulation experiment to examine drought resistance and recovery at five temperate and Mediterranean grassland sites. Aboveground biomass production declined by 30% due to experimental drought (standardised local extremity by rainfall exclusion for 72-98 consecutive days). Species richness did not affect resistance but promoted recovery. Recovery was only positively affected by species richness in low-productive communities, with most diverse communities even showing overcompensation. This positive diversity effect could be linked to asynchrony of species responses. Our results suggest that a more context-dependent view considering the nature of the climatic disturbance as well as the productivity of the studied system will help identify under which circumstances biodiversity promotes drought resistance or recovery. Stability of biomass production can generally be expected to decrease with biodiversity loss and climate change.
Assuntos
Biodiversidade , Secas , Ecossistema , Pradaria , Biomassa , Mudança Climática , Fenômenos Fisiológicos Vegetais , Especificidade da EspécieRESUMO
Ecological theory predicts close relationships between macroclimate and functional traits. Yet, global climatic gradients correlate only weakly with the trait composition of local plant communities, suggesting that important factors have been ignored. Here, we investigate the consistency of climate-trait relationships for plant communities in European habitats. Assuming that local factors are better accounted for in more narrowly defined habitats, we assigned > 300,000 vegetation plots to hierarchically classified habitats and modelled the effects of climate on the community-weighted means of four key functional traits using generalized additive models. We found that the predictive power of climate increased from broadly to narrowly defined habitats for specific leaf area and root length, but not for plant height and seed mass. Although macroclimate generally predicted the distribution of all traits, its effects varied, with habitat-specificity increasing toward more narrowly defined habitats. We conclude that macroclimate is an important determinant of terrestrial plant communities, but future predictions of climatic effects must consider how habitats are defined.
Assuntos
Ecossistema , Plantas , Europa (Continente) , SementesRESUMO
Species abundance distributions (SADs) link species richness with species abundances and are an important tool in the quantitative analysis of ecological communities. Niche-based and sample-based SAD models predict different spatial scaling properties of SAD parameters. However, empirical research on SAD scaling properties is largely missing. Here we extracted percentage cover values of all occurring vascular plants as proxies of their abundance in 1725 10-m2 plots from the GrassPlot database, covering 47 regional data sets of 19 different grasslands and other open vegetation types of the Palaearctic biogeographic realm. For each plot, we fitted the Weibull distribution, a model that is able to effectively mimic other distributions like the log-series and lognormal, to the species-log abundance rank order distribution. We calculated the skewness and kurtosis of the empirical distributions and linked these moments, along with the shape and scale parameters of the Weibull distribution, to plot climatic and soil characteristics. The Weibull distribution provided excellent fits to grassland plant communities and identified four basic types of communities characterized by different degrees of dominance. Shape and scale parameter values of local communities on poorer soils were largely in accordance with log-series distributions. Proportions of subdominant species tended to be lower than predicted by the standard lognormal SAD. Successive accumulation of plots of the same vegetation type yielded nonlinear spatial scaling of SAD moments and Weibull parameters. This scaling was largely independent of environmental correlates and geographic plot position. Our findings caution against simple generalizations about the mechanisms that generate SADs. We argue that in grasslands, lognormal-type SADs tend to prevail within a wider range of environmental conditions, including more extreme habitats such as arid environments. In contrast, log-series distributions are mainly restricted to comparatively species-rich communities on humid and fertile soils.
Assuntos
Ecossistema , Pradaria , Biodiversidade , Biota , SoloRESUMO
ETHNOBOTANICAL RELEVANCE: The aim of this study is to document and describe important ethnobotanical features of 14 villages of Turgutlu (Manisa - Turkey). MATERIALS AND METHODS: The regular ethnobotanical surveys were carried out during different seasons in the years 2009 and 2010 in 14 villages of Turgutlu. The data was collected from 91 village inhabitants using semi-structured interviews. Use value (UV) was used to calculate the relative importance of species known by the inhabitants. Informant Consensus Factor (FIC) was used to calculate the level of homogeneity of diseases. RESULTS: Twenty-nine plant families and 54 plant species were found in this ethnobotanical survey. Among them, 22 (40.7%) species were wild and 32 (59.3%) species were cultivated plants. Rosaceae (14.8%), Asteraceae (9.3%), Lamiaceae (9.3%), Apiaceae (5.6%) and Brassicaceae (5.6%) were the most common plant families. According to results of the use value (UV) calculations, Agropyron repens (L.) P.Beauv., Lactuca sativa L., Beta vulgaris L. var. crassa (Alef.) Helm, Spinacia oleracea L., Brassica nigra (L.) Koch, Capsella bursa-pastoris L. and Eugenia caryophyllata Thunb. yielded the highest use value. Consensus Informants Factor (FIC) ranges were between 0.87 and 0.95. Blood disorders, wounds, dermatological diseases and chest infections were 0.95, 0.93, 0.92, 0.90 while both gastrointestinal and skeletomuscular ailments were 0.87 informant consensus values, respectively. CONCLUSIONS: The usage of medicinal plants for traditional healers is still popular among the inhabitants of the village. This study documents valuable information for traditional remedies and contributes to the usage of medicinal plants in the research area.
Assuntos
Medicina Tradicional , Plantas Medicinais , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Inquéritos e Questionários , TurquiaRESUMO
ETHNOBOTANICAL RELEVANCE: Turkey is one of the richest countries in terms of plant diversity, owing to its unique geographical location with different climatic and geomorphological structures. For this reason interest in ethnobotanical studies has been rising. The goal of this study is to document traditional uses of medicinal plants and supply phytomedicines with efficacy and safety for use in primary health care in Bozüyük in Bilecik district, located in the nortwestern part of Anatolia in Turkey. MATERIALS AND METHODS: The ethnomedicinal data was collected during 2009-2010 using semi-structured questionnaires, personal interviews and group discussion with 60 informants (22 men and 38 women). As a statistical method, informant consensus factors (FIC) and fidelity level (FL) values were calculated to analyze the importance of ethnobotanical plant species. RESULTS: 104 Plant species belonging to 47 families were found in this study. Among them 59 species were wild and 45 species were cultivated plants. The most common wild species belongs to Lamiaceae (15.3%), Apiaceae (6.8%), Fabaceae (5.1%), Asteraceae (5.1%), Polygonaceae (5.1%) and the most common cultivated species belongs to Rosaceae (24.4%), Apiaceae (11.1%), Fabaceae (11.1%), Brassicaceae (8.9%) and Poaceae (6.7%) families. The most common preperation method is infusion with the rate of 45%. According to use value (UV) the most important plant is Linum usitatissimum L. (0.86). The highest Consensus Informants Factor (FIC) of the ailments are skeletomuscular and conjunctivitis diseases with the same value of 0.80. The most frequent species is Mentha longifolia (L.) Hudson which is used for diuretic ailments with the amount of 88.33% fidelity level. CONCLUSIONS: This paper reserves valuable ethnobotanical information for research area. The importance of traditional medicines and indigenous knowledge should be conserved and encouraged. In addition to this further laboratory investigations should be conducted on plants to produce pharmaceutical output.