01978nas a2200157 4500008004100000245013100041210006900172300001000241490000700251520142400258100002101682700001801703700001501721700001601736856006801752 2016 eng d00aBison and cattle grazing management, bare ground coverage, and links to suspended sediment concentrations in grassland streams0 aBison and cattle grazing management bare ground coverage and lin a16-300 v523 a

This study quantified the impact of bison and cattle grazing management practices on bare ground coverage at the watershed, riparian, and forested riparian scales within the Flint Hills ecoregion in Kansas. We tested for correlations between bare ground coverage and fluvial suspended sediment concentrations during base-flow and storm-flow events. We used remotely sensed imagery combined with field surveys to classify ground cover and quantify the presence of bare ground. Base-flow water samples were collected bi-monthly during rain-free periods and 24 h following precipitation events. Storm-flow water samples were collected on the rising limb of the hydrograph, using single-stage automatic samplers. Ungrazed treatments contained the lowest coverage of bare ground at the watershed, riparian, and forested riparian scales. Bison treatments contained the highest coverage of bare ground at the watershed scale, while high-density cattle treatments contained the highest coverage of bare ground at the riparian and forested riparian scales. In bison and cattle-grazed treatments, a majority of bare ground was located near fence lines, watershed boundaries, and third- and fourth-order stream segments. Inorganic sediment concentrations at base flow were best predicted by riparian bare ground coverage, while storm-flow sediment concentrations were best predicted by watershed scale bare ground coverage.

1 aGrudzinski, B.P.1 aDaniels, M.D.1 aAnibas, K.1 aSpencer, D. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/1752-1688.1236402375nas a2200241 4500008004100000245010700041210006900148300001000217490000700227520167000234653001701904653001001921653001001931653001601941653001701957653001101974100001801985700001702003700001702020700001802037700002102055856005702076 2015 eng d00aThe Stream Biome Gradient Concept: factors controlling lotic systems across broad biogeographic scales0 aStream Biome Gradient Concept factors controlling lotic systems  a1 -190 v343 a

We propose the Stream Biome Gradient Concept as a way to predict macroscale biological patterns in streams. This concept is based on the hypothesis that many abiotic and biotic features of streams change predictably along climate (temperature and precipitation) gradients because of direct influences of climate on hydrology, geomorphology, and interactions mediated by terrestrial vegetation. The Stream Biome Gradient Concept generates testable hypotheses related to continental variation among streams worldwide and allows aquatic scientists to understand how results from one biome might apply to a less-studied biome. Some predicted factors change monotonically across the biome/climate gradients, whereas others have maxima or minima in the central portion of the gradient. For example, predictions across the gradient from drier deserts through grasslands to wetter forests include more permanent flow, less bare ground, lower erosion and sediment transport rates, decreased importance of autochthonous C inputs to food webs, and greater stream animal species richness. In contrast, effects of large ungulate grazers on streams are expected to be greater in grasslands than in forests or deserts, and fire is expected to have weaker effects in grassland streams than in desert and forest streams along biome gradients with changing precipitation and constant latitude or elevation. Understanding historic patterns among biomes can help describe the evolutionary template at relevant biogeographic scales, can be used to broaden other conceptual models of stream ecology, and could lead to better management and conservation across the broadest scales.

10abiogeography10abiome10alotic10amacro-scale10amacrosystems10astream1 aDodds, W., K.1 aGido, K., B.1 aWhiles, M.R.1 aDaniels, M.D.1 aGrudzinski, B.P. uhttps://www.journals.uchicago.edu/doi/10.1086/67975602394nas a2200313 4500008004100000245009600041210006900137300001300206490000700219520149500226653001601721653001401737653001201751653001501763653001201778653002001790653001201810653002201822653001901844653002101863653002701884100001701911700002101928700001801949700001801967700001701985700001902002856005902021 2013 eng d00aBlazing and grazing: influences of fire and bison on tallgrass prairie stream water quality0 aBlazing and grazing influences of fire and bison on tallgrass pr a779 -7910 v323 a

Fire and grazers (such as Bison bison) were historically among the most important agents for maintaining and managing tallgrass prairie, but we know little about their influences on water-quality dynamics in streams. We analyzed 2 y of data on total suspended solids (TSS), total N (TN), and total P (TP) (3 samples per week per stream during flow) in 3 prairie streams with fire and bison grazing treatments at Konza Prairie Biological Station, Kansas (USA), to assess whether fire and bison increase the concentrations of these water-quality variables. We quantified the spatial and temporal locations of bison (∼0.21 animal units/ha) with Global Positioning System collars and documented bison trails, paw patches, wallows, and naturally exposed sediment patches within riparian buffers. Three weeks post-fire, TN and TP decreased (t-test, p < 0.001), but TSS did not change. Bison spent <6% of their time within 10 m of the streams, increased the amount of exposed sediment in the riparian areas, and avoided wooded mainstem branches of stream (χ2 test, p < 0.001). Temporal trends suggest that low discharge or increased bison density in the stream may increase TSS and TP during the summer months. Our results indicate a weak connection between TSS and nutrients with bison access to streams over our 2-y study and indicate that low TSS and nutrients characterize tallgrass prairie streams with fire and moderate bison densities relative to surrounding land uses.

10aBison bison10aBos bison10aburning10aGrasslands10agrazers10aprescribed fire10astreams10atallgrass prairie10atotal nitrogen10atotal phosphorus10atotal suspended solids1 aLarson, D.M.1 aGrudzinski, B.P.1 aDodds, W., K.1 aDaniels, M.D.1 aSkibbe, A.M.1 aJoern, Anthony uhttps://www.journals.uchicago.edu/doi/10.1899/12-118.1