02194nas a2200145 4500008004100000245009700041210006900138260002500207520168500232100001801917700002001935700002301955700002101978856004901999 2015 eng d00aA statistical approach for predicting grassland degradation in disturbance-driven landscapes0 astatistical approach for predicting grassland degradation in dis aAnnecy, FrancebIEEE3 a
The relationship between fire and long-term trends in tallgrass prairie vegetation was assessed at Fort Riley and Konza Prairie Biological Station (KPBS) in Kansas. Linear trends of surface greenness were previously estimated using BFAST and MODIS MOD13Q1 NDVI composite images from 2001 to 2010. To explain trends, fire frequency and seasonality (fire regime) was determined and each site was divided into spatial strata using administrative or management units. Generalized linear models (GLM) were used to explain trends by fire regime and/or stratification. Spatialized versions of GLMs were also computed address unexplained spatial components. Non-spatial models for FRK showed fire regime explained only 4% of trends compared to strata (7-26%). At KPBS, fire regime and spatial stratification explained 14% and 39%, respectively. At both sites, improvements in performance were minimal using both fire and strata as explanatory variables. Model spatialization resulted in a 5% improvement at FRK, but with weak spatial structure in the residuals, and was not necessary at KPBS as the existing stratification most of the spatial structure in model residuals. All models at KPBS performed better for each explanatory variable and combination tested. Fire has only a marginal effect on vegetation trends at FRK despite its widespread use as a grassland management tool to improve vegetation health, and explains much more of the trends at KPBS. Analysis of predictors from spatial models with existing stratification yielded an approach with fewer strata but similar performance and may provide insight about additional explanatory variables omitted from this analysis.
1 aJacquin, Anne1 aGoulard, Michel1 aHutchinson, J.M.S.1 aHutchinson, S.L. uhttps://ieeexplore.ieee.org/document/724575901558nas a2200181 4500008004100000245006500041210006100106300001500167490000800182520099700190100001701187700002301204700001701227700001701244700002101261700001701282856007701299 2012 eng d00aThe timing of climate variability and grassland productivity0 atiming of climate variability and grassland productivity a3401 -34050 v1093 aChanges in precipitation amount and variability have the potential to alter the structure and function of grasslands, but we know little about how changes in the timing of precipitation might affect grasslands. Here, we analyze long-term records from a tallgrass prairie to show that shifts in the timing of precipitation during the growing season have little effect on primary productivity or grass reproduction, but can greatly affect grazer performance. While greater late-season precipitation increases the weight gain of adult and young bison, greater mid-season precipitation decreases their weight gain. In addition, calving rates are lower after years with greater mid-season precipitation and higher after years with greater late-season precipitation. As well-timed drought can actually increase grazer weight gain and reproduction, it will be necessary to generate predictions of within-season distribution of precipitation to successfully forecast future grazer performance.
1 aCraine, J.M.1 aNippert, Jesse, B.1 aElmore, A.J.1 aSkibbe, A.M.1 aHutchinson, S.L.1 aBrunsell, N. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-0706.2012.20400.x00603nas a2200157 4500008004100000245009400041210006900135300001300204490000700217100001700224700002300241700002100264700002000285700002100305856011900326 2009 eng d00aThe water budget, climate variability, and climate impacts assessment in Northeast Kansas0 awater budget climate variability and climate impacts assessment a189 -1960 v321 aWilson, I.E.1 aHarrington, J., J.1 aMcLauchlan, K.K.1 aMartinson, E.J.1 aHutchinson, S.L. uhttp://lter.konza.ksu.edu/content/water-budget-climate-variability-and-climate-impacts-assessment-northeast-kansas00516nas a2200133 4500008004100000245008400041210006900125300001300194490000700207100002100214700002000235700002000255856010700275 2008 eng d00aDevelopment of water usage coefficients for the fully-watered tallgrass prairie0 aDevelopment of water usage coefficients for the fullywatered tal a153 -1590 v511 aHutchinson, S.L.1 aKoelliker, J.K.1 aKnapp, Alan, K. uhttp://lter.konza.ksu.edu/content/development-water-usage-coefficients-fully-watered-tallgrass-prairie