TY  - JOUR
A1  - Simons, Nadja K.
A1  - Lewinsohn, Thomas
A1  - Bluethgen, Nico
A1  - Buscot, Francois
A1  - Boch, Steffen
A1  - Daniel, Rolf
A1  - Gossner, Martin M.
A1  - Jung, Kirsten
A1  - Kaiser, Kristin
A1  - Müller, Jörg
A1  - Prati, Daniel
A1  - Renner, Swen C.
A1  - Socher, Stephanie A.
A1  - Sonnemann, Ilja
A1  - Weiner, Christiane N.
A1  - Werner, Michael
A1  - Wubet, Tesfaye
A1  - Wurst, Susanne
A1  - Weisser, Wolfgang W.
T1  - Contrasting effects of grassland management modes on species-abundance distributions of multiple groups
JF  - Agriculture, ecosystems & environment : an international journal for scientific research on the relationship of agriculture and food production to the biosphere
N2  - Intensive land use is a major cause of biodiversity loss, but most studies comparing the response of multiple taxa rely on simple diversity measures while analyses of other community attributes are only recently gaining attention. Species-abundance distributions (SADs) are a community attribute that can be used to study changes in the overall abundance structure of species groups, and whether these changes are driven by abundant or rare species. We evaluated the effect of grassland management intensity for three land-use modes (fertilization, mowing, grazing) and their combination on species richness and SADs for three belowground (arbuscular mycorrhizal fungi, prokaryotes and insect larvae) and seven aboveground groups (vascular plants, bryophytes and lichens; arthropod herbivores; arthropod pollinators; bats and birds). Three descriptors of SADs were evaluated: general shape (abundance decay rate), proportion of rare species (rarity) and proportional abundance of the commonest species (dominance). Across groups, taxonomic richness was largely unaffected by land-use intensity and only decreased with increasing mowing intensity. Of the three SAD descriptors, abundance decay rate became steeper with increasing combined land-use intensity across groups. This reflected a decrease in rarity among plants, herbivores and vertebrates. Effects of fertilization on the three descriptors were similar to the combined land-use intensity effects. Mowing intensity only affected the SAD descriptors of insect larvae and vertebrates, while grazing intensity produced a range of effects on different descriptors in distinct groups. Overall, belowground groups had more even abundance distribtitions than aboveground groups. Strong differences among aboveground groups and between above- and belowground groups indicate that no single taxonomic group can serve as an indicator for effects in other groups. In the past, the use of SADs has been hampered by concerns over theoretical models underlying specific forms of SADs. Our study shows that SAD descriptors that are not connected to a particular model are suitable to assess the effect of land use on community structure.
KW  - Biodiversity
KW  - Cutting frequency
KW  - Management intensity
KW  - Rank-abundance
KW  - Species loss
KW  - Rarity
Y1  - 2017
U6  - https://doi.org/10.1016/j.agee.2016.12.022
SN  - 0167-8809
SN  - 1873-2305
VL  - 237
SP  - 143
EP  - 153
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Frieler, Katja
A1  - Schauberger, Bernhard
A1  - Arneth, Almut
A1  - Balkovic, Juraj
A1  - Chryssanthacopoulos, James
A1  - Deryng, Delphine
A1  - Elliott, Joshua
A1  - Folberth, Christian
A1  - Khabarov, Nikolay
A1  - Müller, Christoph
A1  - Olin, Stefan
A1  - Pugh, Thomas A. M.
A1  - Schaphoff, Sibyll
A1  - Schewe, Jacob
A1  - Schmid, Erwin
A1  - Warszawski, Lila
A1  - Levermann, Anders
T1  - Understanding the weather signal in national crop-yield variability
JF  - Earths future
N2  - Year-to-year variations in crop yields can have major impacts on the livelihoods of subsistence farmers and may trigger significant global price fluctuations, with severe consequences for people in developing countries. Fluctuations can be induced by weather conditions, management decisions, weeds, diseases, and pests. Although an explicit quantification and deeper understanding of weather-induced crop-yield variability is essential for adaptation strategies, so far it has only been addressed by empirical models. Here, we provide conservative estimates of the fraction of reported national yield variabilities that can be attributed to weather by state-of-the-art, process-based crop model simulations. We find that observed weather variations can explain more than 50% of the variability in wheat yields in Australia, Canada, Spain, Hungary, and Romania. For maize, weather sensitivities exceed 50% in seven countries, including the United States. The explained variance exceeds 50% for rice in Japan and South Korea and for soy in Argentina. Avoiding water stress by simulating yields assuming full irrigation shows that water limitation is a major driver of the observed variations in most of these countries. Identifying the mechanisms leading to crop-yield fluctuations is not only fundamental for dampening fluctuations, but is also important in the context of the debate on the attribution of loss and damage to climate change. Since process-based crop models not only account for weather influences on crop yields, but also provide options to represent human-management measures, they could become essential tools for differentiating these drivers, and for exploring options to reduce future yield fluctuations.
Y1  - 2017
U6  - https://doi.org/10.1002/2016EF000525
SN  - 2328-4277
VL  - 5
SP  - 605
EP  - 616
PB  - Wiley
CY  - Hoboken
ER  -