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Experimental drought consistently underestimates productivity responses to natural drought in four Central US grasslandsNARA Subscribed
Climate change is increasing the frequency and severity of droughts globally, and grasslands are particularly vulnerable to such hydrological extremes. Drought effects at the ecosystem scale have been assessed both experimentally and through the study of naturally occurring drought, with emerging evidence that the magnitude of drought effects may vary depending on the approach used. We took advantage of a decadal study of four...
Environmental Heterogeneity Imposed by Photovoltaic Array Alters Grassland Soil Microbial CommunitiesNARA Subscribed
The rapid expansion of photovoltaic (PV) energy production has generated concern over its potential ecosystem impacts. PV arrays induce unique microenvironmental conditions by altering resource availability and substantially impacting aboveground processes. However, the belowground consequences of PV development are understudied, limiting our understanding of overall ecosystem impacts. Here, we paired soil physiochemical, mole...
Extreme Drought Decreases the Stability of Above‐ but Not Below‐Ground Productivity Across Eurasian SteppesNARA Subscribed
Ecological stability plays a crucial role in determining the sustainability of ecosystem functioning and nature's contribution to people. Although the disruptive effects of extreme drought on ecosystem structure and functions are widely recognized, their effect on the stability of above‐ and belowground productivity remains understudied. We assessed the effects of drought on ecosystem stability using a 3‐year drought experimen...
Extreme Drought Increases the Temporal Variability of Grassland Productivity by Suppressing Dominant GrassesNARA Subscribed
Extreme droughts are intensifying, yet their impact on temporal variability of grassland functioning and its drivers remains poorly understood. We imposed a 6‐year extreme drought in two semiarid grasslands to explore how drought influences the temporal variability of ANPP and identify potential stabilising mechanisms. Drought decreased ANPP while increasing its temporal variability across grasslands. In the absence of drought...
Grassland sensitivity to drought is related to functional composition across E ast A sia and N orth A mericaNARA Subscribed
Plant traits can be helpful for understanding grassland ecosystem responses to climate extremes, such as severe drought. However, intercontinental comparisons of how drought affects plant functional traits and ecosystem functioning are rare. The Extreme Drought in Grasslands experiment (EDGE) was established across the major grassland types in East Asia and North America (six sites on each continent) to measure variability in...
Accounting for herbaceous communities in process‐based models will advance our understanding of “grassy” ecosystemsNARA Subscribed
Grassland and other herbaceous communities cover significant portions of Earth's terrestrial surface and provide many critical services, such as carbon sequestration, wildlife habitat, and food production. Forecasts of global change impacts on these services will require predictive tools, such as process‐based dynamic vegetation models. Yet, model representation of herbaceous communities and ecosystems lags substantially behin...
The detection and attribution of extreme reductions in vegetation growth across the global land surfaceNARA Subscribed
Negative extreme anomalies in vegetation growth (NEGs) usually indicate severely impaired ecosystem services. These NEGs can result from diverse natural and anthropogenic causes, especially climate extremes (CEs). However, the relationship between NEGs and many types of CEs remains largely unknown at regional and global scales. Here, with satellite‐derived vegetation index data and supporting tree‐ring chronologies, we identif...
Responses of a semiarid grassland to recurrent drought are linked to community functional compositionNARA Subscribed
Recurrent droughts are an inevitable consequence of climate change, yet how grasslands respond to such events is unclear. We conducted a 6‐year rainfall manipulation experiment in a semiarid grassland that consisted of an initial 2‐year drought (2015–2016), followed by a recovery period (2017–2018) and, finally, a second 2‐year drought (2019–2020). In each year, we estimated aboveground net primary productivity (ANPP), species...
Key Message Several Fusarium wilt resistance genes were discovered, genetically and physically mapped, and rapidly deployed via marker-assisted selection to develop cultivars resistant to Fusarium oxysporum f. sp. fragariae , a devastating soil-borne pathogen of strawberry . Abstract Fusarium wilt, a soilborne disease caused by Fusarium oxysporum f. sp. fragariae , poses a significant threat to strawberry ( Fragaria $$\times$$...
Compound hydroclimatic extremes in a semi‐arid grassland: Drought, deluge, and the carbon cycleNARA Subscribed
Climate change is predicted to increase the frequency and intensity of extreme events including droughts and large precipitation events or “deluges.” While many studies have focused on the ecological impacts of individual events (e.g., a heat wave), there is growing recognition that when extreme events co‐occur as compound extremes, (e.g., a heatwave during a drought), the additive effects on ecosystems are often greater than...
Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline...
Seasonal changes in GPP/SIF ratios and their climatic determinants across the Northern HemisphereNARA Subscribed
Satellite‐derived sun‐induced chlorophyll fluorescence (SIF) has been increasingly used for estimating gross primary production (GPP). However, the relationship between SIF and GPP has not been well defined, impeding the translation of satellite observed SIF to GPP. Previous studies have generally assumed a linear relationship between SIF and GPP at daily and longer time scales, but support for this assumption is lacking. Here...
Plant traits and soil fertility mediate productivity losses under extreme drought in C 3 grasslandsNARA Subscribed
Extreme drought decreases aboveground net primary production (ANPP) in most grasslands, but the magnitude of ANPP reductions varies especially in C 3 ‐dominated grasslands. Because the mechanisms underlying such differential ecosystem responses to drought are not well resolved, we experimentally imposed an extreme 4‐yr drought (2015–2018) in two C 3 grasslands that differed in aridity. These sites had similar annual precipitat...