@article {JRN54396,
	title = {Soil animal responses to moisture availability are largely scale, not ecosystem dependent: Insight from a cross-site study},
	journal = {Global Change Biology},
	volume = {20},
	year = {2014},
	month = {02/2014},
	pages = {2631-2643},
	chapter = {2631},
	abstract = {<p class="rtejustify">Climate change will result in reduced soil water availability in much of the world either due to changes in precipitation or increased temperature and evapotranspiration. Responses of communities of mites and nematodes to changes in moisture availability are not well known, yet these organisms play important roles in decomposition and nutrient cycling processes. We determined how communities of these organisms respond to changes in moisture availability and whether common patterns occur along fine-scale gradients of soil moisture within four individual ecosystem types (mesic, xeric and arid grasslands and a polar desert) located in the western United States and Antarctica, as well as across a cross-ecosystem moisture gradient (CEMG) of all four ecosystems considered together. An elevation transect of three sampling plots was monitored within each ecosystem and soil samples were collected from these plots and from existing experimental precipitation manipulations within each ecosystem once in fall of 2009 and three times each in 2010 and 2011. We found that while both mites and nematodes increased with available soil moisture across the CEMG, within individual ecosystems increases in soil moisture resulted in decreases to nematode communities at all but the arid grassland ecosystem; mites showed no responses at any ecosystem. Changes in proportional abundances of mite and nematode trophic groups as soil moisture increased within individual ecosystems may result in shifts within soil food webs with important consequences for ecosystem functioning. We suggest that communities of soil animals at local scales may respond predictably to changes in moisture availability regardless of ecosystem type but that additional factors, such as climate variability, vegetation composition and soil properties may influence this relationship over larger scales.</p>
},
	keywords = {climate change, desert, drought, grassland, mites, nematodes},
	doi = {10.1111/gcb.12522},
	url = {/files/bibliography/14-037.pdf},
	author = {Sylvain, Zachary A. and D.H. Wall and Karie Cherwin and Lara Reichmann and Debra C. Peters and O. E. Sala}
}
@proceedings {JRN54534,
	title = {Patterns of soil community structure differ by scale and ecosystem type along a large-scale precipitation gradient},
	volume = {COS 128-8},
	year = {2012},
	month = {08/2012},
	publisher = {Ecological Society of America Abstracts},
	address = {Portland, Oregon},
	abstract = {Climate models predict increased variability in precipitation regimes, which will likely increase frequency/duration of drought. Reductions in soil moisture affect physical and chemical characteristics of the soil habitat and can influence soil organisms such as mites and nematodes. These organisms perform important roles in decomposition and nutrient cycling: changes to their community structuring have been shown to influence their contributions to these ecosystem processes. We investigated how soil moisture variation across regional scales might influence the community structure and population dynamics of mites and nematodes. Research consisted of three types of precipitation regimes: 1) a regional scale precipitation gradient of wet to dry: two grassland (wet{\textemdash}Konza Prairie, KS{\textemdash}KNZ; arid{\textemdash}Shortgrass Steppe, CO{\textemdash}SGS) and two desert (hot{\textemdash}Jornada Basin, NM{\textemdash}JRN; cold{\textemdash}McMurdo Dry Valleys, Antarctica{\textemdash}MCM) long-term ecological research (LTER) sites across the western US and Antarctica; 2) landscape-scale soil moisture gradients of three plots along a topographic transect at each site; and 3) existing experiments at each site manipulating natural variation in moisture availability. For 2 and 3, soil samples were collected once in fall of 2009 and three times each in 2010 and 2011, with nematodes and mites extracted, counted and sorted to trophic groups.  Ordination analyses revealed that while nematode communities within two of the drier sites of the gradient (JRN and SGS) are similar, those of KNZ and MCM (the wettest and driest sites, respectively) are noticeably different. Regression analyses indicated patterns for nematode trophic groups across the entire gradient differ from those within individual sites; for example, across the entire gradient numbers of plant-feeding nematodes increase with available soil moisture, but within individual sites this pattern is only seen at JRN and decreases are observed at SGS and KNZ. In contrast, fungivorous nematodes increased with moisture across the entire gradient, while the only site displaying an increase was KNZ. Preliminary mite analyses suggest that mites also respond differently across different scales and sites. Soil moisture effects on soil invertebrate community structure appear to be dependent upon scale and ecosystem type. Notably, while populations of mites and nematodes tend to increase as sites increase in annual precipitation, in many cases populations decrease within sites as soil moisture increases. Future work will examine how modeling techniques may be employed to forecast changes to soil communities as moisture regimes are altered across regional and local scales.},
	author = {Sylvain, Zachary A. and D.H. Wall and Karie Cherwin and Debra C. Peters and O. E. Sala and Lara Reichmann}
}
