Communities of different plant diversity respond similarly to drought stress: experimental evidence from field non-weeded and greenhouse conditions

Abstract

Accelerating rate of species loss has prompted researchers to study the role of species diversity in processes that control ecosystem functioning. Although negative impact of species loss has been documented, the evidence concerning its impact on ecosystem stability is still limited. Here, we studied the effects of declining species and functional diversity on plant community responses to drought in the field (open to weed colonization) and greenhouse conditions. Both species and functional diversity positively affected the average yields of field communities. However, this pattern was similar in both drought-stressed and control plots. No effect of diversity on community resistance, biomass recovery after drought and resilience was found because drought reduced biomass production similarly at each level of diversity by approximately 30%. The use of dissimilarity (characterized by Euclidean distance) revealed higher variation under changing environments (drought-stressed vs. control) in more diverse communities compared to less species-rich assemblages. In the greenhouse experiment, the effect of species diversity affected community resistance, indicating that more diverse communities suffered more from drought than species-poor ones. We conclude that our study did not support the insurance hypothesis (stability properties of a community should increase with species richness) because species diversity had an equivocal effect on ecosystem resistance and resilience in an environment held under non-weeded practice, regardless of the positive relationship between sown species diversity and community biomass production. More species-rich communities were less resistant against drought-stressed conditions than species-poor ones grown in greenhouse conditions.

Forage legumes for future dry climates: Lower relative biomass losses of minor forage legumes compared to Trifolium repens under conditions of periodic drought stress

“…For L. corniculatus, Lanta et al. () found BM losses under drought stress in a range comparable to that in the present study. Among investigated legumes here, M. falcata is known for its tolerance towards drought stress, which is likely to be induced by dehydrin accumulation (Close, ).…”

“…() have shown good performance of Onobrychis viciifolia under periodic drought stress when harvested at optimal stages. Under conditions of higher temperatures and drought, another forage legume, Lotus corniculatus , performed well and had a good water‐use efficiency at higher temperatures and drought (Carter, Theodorou, & Morris, ; Kostopoulou & Karatassiou, ; Lanta, Doležal, Zemková, & Lepš, ). Minor forage legumes may have lower moisture requirements than white clover and can remain competitive against less desirable species with high biomass production under drought stress (Gilgen, Signarbieux, Feller, & Buchmann, ; Grant et al., ).…”

“…White clover (Trifolium repens) is currently the dominant forage legume in temperate permanent grasslands as it provides high productivity and a favourable forage quality under grazing and cutting (Frame, Charlton, & Laidlaw, 1998;Rochon et al, 2004;Topp & Doyle, 2004). Inclusion of legumes in permanent grasslands generally increases the forage quality due to higher protein contents, slower maturation rates and lower structural Karatassiou, 2017;Lanta, Doležal, Zemková, & Lepš, 2012). Minor forage legumes may have lower moisture requirements than white clover and can remain competitive against less desirable species with high biomass production under drought stress (Gilgen, Signarbieux, Feller, & Buchmann, 2010;Grant et al, 2014).…”

Patterns and drivers of biodiversity–stability relationships under climate extremes

“…For example, the most studied type of extreme, drought, can be short term (mostly weeks or months) with (almost) no precipitation (pulse event, e.g. Lanta, Dolezal, Zemkova, & Leps, ), or long term (months to years) with prolonged precipitation deficits (press event, e.g. Evans, Byrne, Lauenroth, & Burke, ).…”

A systematic review of ecological attributes that confer resilience to climate change in environmental restoration

“…Not all findings support the insurance hypothesis. For example, in a greenhouse experiment, Lanta et al [57] found that high species richness and functional diversity provided less resistance against drought stressed conditions than less diverse species assemblages. The same study found no effect of diversity on community resistance under outdoor experimental conditions.…”