Academic literature on the topic 'Landscape assessment – Kansas – Flint Hills'

Abstract Grassland birds have declined more than any other avian assemblage in North America, with nearly every species showing negative population trends. In the Flint Hills of Kansas, the largest remnant of the tallgrass prairie biome, annual spring burning of rangeland has recently replaced burning every 2–3 years. I examined effects of different burning and bison (Bos bison) grazing regimes on June abundances of seven bird species using a 23-year data set from the Konza Prairie Biological Station. Fire significantly affected the abundances of six of the seven species. Effects varied among species but, notably, four grass-dependent species—Grasshopper Sparrow (Ammodramus savannarum), Henslow’s Sparrow (A. henslowii), Dickcissel (Spiza americana), and Eastern Meadowlark (Sturnella magna)— and the shrub-dependent Bell’s Vireo (Vireo bellii)—were least abundant or absent at sites in the breeding season immediately following burning. Upland Sandpipers (Bartramia longicauda) were most abundant at sites in the season following burning, whereas Brown-headed Cowbirds (Molothrus ater) exhibited no significant response. Bison grazing increased abundance of Upland Sandpiper and Grasshopper Sparrow, nearly eliminated Henslow’s Sparrow, and (in combination with recent fire) lowered the abundance of Dickcissel. Although fire and grazing are natural forces that maintain tallgrass prairie, their action was, until recently, intermittent and patchy, providing grassland birds with a variety of levels of disturbance. If the vast Flint Hills prairie is to serve as a grassland bird stronghold, the region-wide practice of annual burning with intensive grazing must be replaced with alternatives that restore heterogeneity to the landscape. Efectos de las Quemas Programadas y del Pastoreo de los Bisontes sobre la Abundancia de Aves Reproductivas en Praderas de Pasto Alto

Abstract. Methods are developed to study hydrologic interactions across the surficial/groundwater interface in a native prairie ecosystem. Surficial ecohydrologic processes are simulated with the USDA's EPIC model using daily climate data from the Kansas Weather Data Library, vegetation and soil data from the USDA, and current land-use management practices. Results show that mean annual precipitation (from 1985–2005) is partitioned into 13% runoff regionally and 14% locally over the Konza LTER, lateral flow through soil is 1% regionally and 2% locally, groundwater recharge is 11% regionally and 9% locally, and evapotranspiration accounts for the remaining 75%. The spatial distribution of recharge was used in a regional Modflow groundwater model that was calibrated to existing groundwater observations and field measurements gathered for this study, giving a hydraulic conductivity in the Flint Hills region of 1–2 m day−1 with a local zone (identified here) of 0.05–0.1 m day−1. The resistance was set to fixed representative values during model calibration of hydraulic conductivity, and simple log-log relations correlate the enhanced recharge beneath ephemeral upland streams and baseflow in perennial lowland streams to the unknown resistance of the streambeds. Enhanced recharge due to stream transmission loss (the difference between terrestrial runoff and streamflow) represents a small fraction of streamflow in the ephemeral upland and the resistance of this streambed is 100 000 day. Long-term baseflow in the local Kings Creek watershed (2% of the groundwater recharge over the watershed) is met when the resistance of the lowland streambed is 1000 day. The coupled framework developed here to study surficial ecohydrological processes using EPIC and groundwater hydrogeological processes using Modflow provides a baseline hydrologic assessment and a computational platform for future investigations to examine the impacts of climate change, vegetative cover, soils, and management practices on hydrologic forcings.

Abstract. Methods are developed to study hydrologic interactions across the surficial/groundwater interface in a native prairie ecosystem. Surficial ecohydrologic processes are simulated with the USDA's EPIC model using daily climate data from the Kansas Weather Data Library, vegetation and soil data from the USDA, and current land-use management practices. Results show that mean annual precipitation (from 1985–2005) is partitioned into 13% runoff regionally and 14% locally over the Konza LTER, lateral flow through soil is 1% regionally and 2% locally, groundwater recharge is 11% regionally and 9% locally, and evapotranspiration accounts for the remaining 75%. The spatial distribution of recharge was used in a regional Modflow groundwater model that was calibrated to existing groundwater observations and field measurements gathered for this study, giving a hydraulic conductivity in the Flint Hills region of 1–2 m day−1 with a local zone (identified here) of 0.05–0.1 m day−1. Simple log-log relations correlate the enhanced recharge beneath ephemeral upland streams and baseflow in perennial lowland streams to the unknown resistance of the streambeds. Enhanced recharge due to stream transmission loss (the difference between terrestrial runoff and streamflow) represents a small fraction of streamflow in the ephemeral upland and the resistance of this streambed is 100 000 day. Long-term baseflow in the local Kings Creek watershed (2% of the groundwater recharge over the watershed) is met when the resistance of the lowland streambed is 1000 day. The coupled framework developed here to study surficial ecohydrological processes using EPIC and groundwater hydrogeological processes using Modflow provides a baseline hydrologic assessment and a computational platform for future investigations to examine the impacts of climate change, vegetative cover, soils, and management practices on hydrologic forcings.

Climate is a fundamental driver of ecosystem structure and function (Prentice et al. 1992). Historically, North American grassland and forest biomes have fluctuated across the landscape in step with century- to millennialscale climate variability (Axelrod 1985; Ritchie 1986). Climate variability of at decadal scale, such as the severe drought of the 1930s in the Central Plains of North America, caused major shifts in grassland plant community composition (Weaver 1954, 1968). However, on a year-to-year basis, climate variability is more likely to affect net primary productivity (NPP; Briggs and Knapp 1995; Knapp et al. 1998; Briggs and Knapp 2001). This is especially true for grasslands, which have recently been shown to display greater variability in net primary production in response to climate variability than forest, desert, or arctic/alpine systems (Knapp and Smith 2001). Although the basic relationships among interannual variability in rainfall, temperature, and grassland NPP have been well studied (Sala et al. 1988; Knapp et al. 1998; Alward et al. 1999), the linkages to major causes of climate variability at quasi-quintennial (~5 years) or interdecadal (~10 year) timescales in the North American continental interior, such as solar activity cycles, the El Niño–Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO), and the North Pacific Index (NP), are less well understood. In this chapter, we will examine how interannual, quasi-quintennial, and interdecadal variation in annual precipitation and mean annual temperature at a tallgrass prairie site (Konza Prairie Biological Station) may be related to indexes of solar activity, ENSO, NAO, and NP, and in turn how these indexes may be related to aboveground net primary productivity (ANPP). Specifically, we present (1) period-spectrum analyses to characterize the predominant timescales of temperature and precipitation variability at Konza Prairie, (2) correlation analyses of quantitative indexes of the major atmospheric processes with Konza temperature and precipitation records, and (3) the implications of variation in major atmospheric processes for seasonal and interannual patterns of ANPP. The Konza Prairie Biological Station (KNZ), which lies in the Flint Hills (39º05' N, 96º35' W), is a 1.6-million-ha region spanning eastern Kansas from the Nebraska border to northeastern Oklahoma (figure 20.1). This region is the largest remaining tract of unbroken tallgrass prairie in North America (Samson and Knopf 1994) and falls in the more mesic eastern portion of the Central Plains grasslands.