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Climate change is increasing the magnitude and frequency of precipitation extremes. Consequently, grassland community dynamics are destabilising and becoming harder to predict since models typically simulate long‐term (asymptotic) behaviour, potentially neglecting short‐term (transient) behaviour. Here, we use cover data from an experiment performed over 8 years to model short‐ and long‐term responses of three functional group...
Tree diversity effects on soil microbial biomass and respiration are context dependent across forest diversity experimentsNARA Subscribed
Aim Soil microorganisms are essential for the functioning of terrestrial ecosystems. Although soil microbial communities and functions are linked to tree species composition and diversity, there has been no comprehensive study of the generality or context dependence of these relationships. Here, we examine tree diversity–soil microbial biomass and respiration relationships across environmental gradients using a global network...
Biotic homogenization destabilizes ecosystem functioning by decreasing spatial asynchronyNARA Subscribed
Our planet is facing significant changes of biodiversity across spatial scales. Although the negative effects of local biodiversity (α diversity) loss on ecosystem stability are well documented, the consequences of biodiversity changes at larger spatial scales, in particular biotic homogenization, that is, reduced species turnover across space (β diversity), remain poorly known. Using data from 39 grassland biodiversity experi...
Increasing effects of chronic nutrient enrichment on plant diversity loss and ecosystem productivity over timeNARA Subscribed
Human activities are enriching many of Earth’s ecosystems with biologically limiting mineral nutrients such as nitrogen (N) and phosphorus (P). In grasslands, this enrichment generally reduces plant diversity and increases productivity. The widely demonstrated positive effect of diversity on productivity suggests a potential negative feedback, whereby nutrient‐induced declines in diversity reduce the initial gains in productiv...
Biodiversity loss decreases ecosystem functioning at the local scales at which species interact, but it remains unclear how biodiversity loss affects ecosystem functioning at the larger scales of space and time that are most relevant to biodiversity conservation and policy. Theory predicts that additional insurance effects of biodiversity on ecosystem functioning could emerge across time and space if species respond asynchrono...
Do the rich get richer? Varying effects of tree species identity and diversity on the richness of understory taxaNARA Subscribed
Understory herbs and soil invertebrates play key roles in soil formation and nutrient cycling in forests. Studies suggest that diversity in the canopy and in the understory are positively associated, but these studies often confound the effects of tree species diversity with those of tree species identity and abiotic conditions. We combined extensive field sampling with structural equation modeling to evaluate the simultaneous...
Contributions of a global network of tree diversity experiments to sustainable forest plantationsNARA Subscribed
The area of forest plantations is increasing worldwide helping to meet timber demand and protect natural forests. However, with global change, monospecific plantations are increasingly vulnerable to abiotic and biotic disturbances. As an adaption measure we need to move to plantations that are more diverse in genotypes, species, and structure, with a design underpinned by science. TreeDivNet, a global network of tree diversity...
General principles from coexistence theory are often invoked to explain how and why mixtures of species outperform monocultures. However, the complementarity and selection effects commonly measured in biodiversity experiments do not precisely quantify the niche and relative fitness differences that govern species coexistence. Given this lack of direct correspondence, how can we know whether species‐rich mixtures are stable and...
Biodiversity effects on ecosystem functioning change along environmental stress gradientsNARA Subscribed
Positive relationship between biodiversity and ecosystem functioning has been observed in many studies, but how this relationship is affected by environmental stress is largely unknown. To explore this influence, we measured the biomass of microalgae grown in microcosms along two stress gradients, heat and salinity, and compared our results with 13 published case studies that measured biodiversity–ecosystem functioning relatio...
Ingestion by an endemic frugivore enhances seed germination of endemic plant species but decreases seedling survival of exoticsNARA Subscribed
Aim To test whether ingestion by endemic frugivores differentially affects the seed germination time, germination percentage and seedling survival of endemic, native and exotic fleshy fruited plant species, and to identify the principal processes and attributes driving such effects. Location Round Island, Mauritius. Methods We conducted a germination and seedling survival experiment for 3 months to test whether ingestion (gut...
Plant growth rates and seed size: a re‐evaluationNARA Subscribed
Small‐seeded plant species are often reported to have high relative growth rate or RGR. However, because RGR declines as plants grow larger, small‐seeded species could achieve higher RGR simply by virtue of their small size. In contrast, size‐standardized growth rate or SGR factors out these size effects. Differences in SGR can thus only be due to differences in morphology, allocation, or physiology. We used nonlinear regressi...
Effects of biodiversity on the functioning of ecosystems: a summary of 164 experimental manipulations of species richnessNARA Subscribed
Over the past decade, accelerating rates of species extinction have prompted an increasing number of studies to reduce the number of species experimentally in a variety of ecosystems and examine how this aspect of diversity alters the efficiency by which communities capture biologically essential resources and convert them into new tissue. Here we summarize the results of 164 experiments (reported in 84 publications) that have...
Conventional functional classification schemes underestimate the relationship with ecosystem functioningNARA Subscribed
Studies linking the functional diversity of a biota to ecosystem functioning typically employ a priori classifications of species into hypothetically complementary groups. However, multiple alternate classifications exist in which the number of functional groups, the number of species per functional group, and the grouping of species differ from the a priori scheme. Without assessing the relative precision, or ability of an a...
How Do Different Measures of Functional Diversity Perform?NARA Subscribed
Overyielding in grassland communities: testing the sampling effect hypothesis with replicated biodiversity experimentsNARA Subscribed
We derive and test some assumptions and predictions of the Sampling Effect Hypothesis (SEH) by examining the relationship between the traits of species in monoculture and their relative abundance in mixture, and by comparing polyculture performance with single‐species plots. Although we found a positive relationship between production in monoculture and dominance in mixtures as predicted by the SEH, the relationship had low ex...
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