@article {KNZ001708, title = {Baseflow physical characteristics differ at multiple spatial scales in stream networks across diverse biomes}, journal = {Landscape Ecology}, volume = {31}, year = {2016}, pages = {119-136}, abstract = {

Context Spatial scaling of ecological processes is facilitated by quantifying underlying habitat attributes. Physical and ecological patterns are often measured at disparate spatial scales limiting our ability to quantify ecological processes at broader spatial scales using physical attributes. Objective We characterized variation of physical stream attributes during periods of high biological activity (i.e., baseflow) to match physical and ecological measurements and to identify the spatial scales exhibiting and predicting heterogeneity. Methods We measured canopy cover, wetted width, water depth, and sediment size along transects of 1st\–5th order reaches in five stream networks located in biomes from tropical forest to arctic tundra. We used hierarchical analysis of variance with three nested scales (watersheds, stream orders, reaches) to identify scales exhibiting significant heterogeneity in attributes and regression analyses to characterize gradients within and across stream networks. Results Heterogeneity was evident at one or multiple spatial scales: canopy cover and water depth varied significantly at all three spatial scales while wetted width varied at two scales (stream order and reach) and sediment size remained largely unexplained. Similarly, prediction by drainage area depended on the attribute considered: depending on the watershed, increases in wetted width and water depth with drainage area were best fit with a linear, logarithmic, or power function. Variation in sediment size was independent of drainage area. Conclusions The scaling of ecologically relevant baseflow physical characteristics will require study beyond the traditional bankfull geomorphology since predictions of baseflow physical attributes by drainage area were not always best explained by geomorphic power laws.

}, keywords = {LTER-KNZ, Boreal forest, Geomorphology, Grasslands, Nested ANOVA, Scaling, Temperate forest}, issn = {0921-2973}, doi = {10.1007/s10980-015-0289-y}, url = {https://link.springer.com/article/10.1007\%2Fs10980-015-0289-y}, author = {R{\"u}egg, Janine and W. K. Dodds and Daniels, M.D. and Sheehan, Ken R. and Baker, Christina L. and W.B. Bowden and Farrell, Kaitlin J. and Flinn, Michael B. and Harms, Tamara K. and Jones, J.B. and Koenig, Lauren E. and Kominoski, John S. and W.H. McDowell and Parker, Samuel P. and Rosemond, Amy D. and Trentman, Matt T. and M.R. Whiles and Wollheim, Wilfred M.} } @article {KNZ001707, title = {Bison and cattle grazing management, bare ground coverage, and links to suspended sediment concentrations in grassland streams}, journal = {Journal of the American Water Resources Association}, volume = {52}, year = {2016}, pages = {16-30}, abstract = {

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.

}, keywords = {LTER-KNZ}, doi = {10.1111/1752-1688.12364}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/1752-1688.12364}, author = {Grudzinski, B.P. and Daniels, M.D. and Anibas, K. and Spencer, D.} } @article {KNZ001660, title = {Fundamental spatial and temporal disconnections in the hydrology of an intermittent prairie headwater network}, journal = {Journal of Hydrology}, volume = {522}, year = {2015}, pages = {305 - 316}, abstract = {

We characterize the hydrology of intermittent prairie headwater streams of the Konza Prairie Biological Station (Konza) located in northeastern Kansas, USA. Flow records from four gaging stations were used to quantify flow intermittence and mean and peak annual discharges. Gage sites used in this analysis are classified as harshly intermittent with all sites having over 90 days of zero-flow annually. The largest basin had the fewest zero-flow days and the shortest durations of zero-flow while the smallest basin had the most zero-flow days and the highest frequency zero-flow durations. There were strong correlations between total annual precipitation and the total number of zero-flow days and the number of zero-flow periods. Correlations were less strong between the Palmer Drought Severity Index (PDSI) and the number of zero-flow days and between PDSI and the number of zero-flow periods. Basin-averaged total annual precipitation poorly predicted mean annual and peak annual discharges. Double mass plots of streamflow to precipitation and streamflow in the headwaters to the receiving stream demonstrate many instances of flow desynchronization. Results of this study suggest that local watershed-scale processes, such as groundwater storage in limestone and alluvial strata, dynamic infiltration flow paths, and soil moisture conditions, produce a threshold-driven hydrologic response, decoupling the headwater hydrologic regimes from sub-annual weather patterns.

}, keywords = {LTER-KNZ, Flood, Great Plains, Intermittent, prairie, Temporary stream}, doi = {10.1016/j.jhydrol.2014.12.031}, url = {https://www.sciencedirect.com/science/article/pii/S0022169414010427?via\%3Dihub}, author = {Costigan, K.H. and Daniels, M.D. and W. K. Dodds} } @article {KNZ001686, title = {The Stream Biome Gradient Concept: factors controlling lotic systems across broad biogeographic scales}, journal = {Freshwater Science.}, volume = {34}, year = {2015}, pages = {1 -19}, abstract = {

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.

}, keywords = {LTER-KNZ, biogeography, biome, lotic, macro-scale, macrosystems, stream}, doi = {10.1086/679756}, url = {https://www.journals.uchicago.edu/doi/10.1086/679756}, author = {W. K. Dodds and K. B. Gido and M.R. Whiles and Daniels, M.D. and Grudzinski, B.P.} } @phdthesis {KNZ001825, title = {Influence of watershed grazing management on stream geomorphology in grassland headwater streams}, volume = {PhD Dissertation}, year = {2014}, school = {Kansas State University}, type = {Ph.D. Thesis}, address = {Manhattan, KS}, abstract = {

This dissertation increases our understanding of the drivers that shape and maintain grassland streams and their watersheds by examining the influence of grazing management practices on suspended sediment concentrations, bare ground production, and changes to channel geomorphology. Chapter 2 demonstrates that cattle grazing produces significantly higher baseflow suspended sediment concentrations relative to bison grazing. Suspended sediment concentrations within bison-grazed streams are similar to ungrazed streams, indicating that the substitution of cattle for bison has resulted in degradation of baseflow water quality in grassland streams. Burning frequency, discharge, and seasonality are also significant drivers of suspended sediment concentrations, but are generally less influential than grazing treatments. Chapter 3 indicates that high density cattle grazing treatments produce more bare ground within the riparian zones of grassland stream networks, particularly underneath tree canopy cover. The increased bare ground coverage within riparian areas is correlated with increased suspended sediment concentrations during baseflow conditions, while watershed-scale bare ground production is correlated with increased suspended sediment concentrations during storm flow events. Chapter 4 demonstrates channel geometry and sedimentology are significantly influenced by grazing treatments. This dissertation is the first study to comparatively evaluate the relative influence between cattle and bison grazing on stream geomorphology within any environment. Insight gained from this project can be used by public and private land use managers to improve the environmental integrity of native grassland ecosystems.

}, keywords = {LTER-KNZ, agriculture, ecology, Fluvial, Geomorphology, Landuse, Sediment}, url = {http://krex.k-state.edu/dspace/handle/2097/18688}, author = {Grudzinski, Bartosz Piotr} } @article {KNZ001537, title = {Blazing and grazing: influences of fire and bison on tallgrass prairie stream water quality}, journal = {Freshwater Science}, volume = {32}, year = {2013}, pages = {779 -791}, abstract = {

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.

}, keywords = {LTER-KNZ, Bison bison, Bos bison, burning, Grasslands, grazers, prescribed fire, streams, tallgrass prairie, total nitrogen, total phosphorus, total suspended solids}, doi = {10.1899/12-118.1}, url = {https://www.journals.uchicago.edu/doi/10.1899/12-118.1}, author = {Larson, D.M. and Grudzinski, B.P. and W. K. Dodds and Daniels, M.D. and Skibbe, A.M. and Anthony Joern} }