Runoff and erosional responses to a drought‐induced shift in a desert grassland community composition

In contrast, measurements on small runoff plots on the hillslopes of the same watershed showed a significant increase in sediment discharge that continued after E. lehmanniana replaced native grasses. Together, these findings suggest alteration in plant community increased sediment yield but that hydrological responses to this event differ at watershed and plot scales, highlighting the geomorphological controls at the watershed scale that determine sediment transport efficiency and storage. Resolving these scalar issues will help identify critical landform features needed to preserve watershed integrity under changing climate conditions.

[1]  James A. Young,et al.  Growth and elemental content of several sagebrush-steppe species in unburned and post-wildfire soil and plant effects on soil attributes , 1994, Plant and Soil.

[2]  S. Solomon.  The Physical Science Basis : Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change , 2007 .

[3]  G. McPherson,et al.  Response of semi‐desert grasslands invaded by non‐native grasses to altered disturbance regimes , 2005 .

[4]  M. Nichols,et al.  Spatial patterns of soil erosion and deposition in two small, semiarid watersheds , 2005 .

[5]  G. Frasier,et al.  Water balance in pure stand of Lehmann lovegrass. , 1994 .

[6]  M. Caldwell,et al.  Competitive ability is linked to rates of water extraction , 1988, Oecologia.

[7]  Roger Jones,et al.  Regional climate projections , 2007 .

[8]  David G. Williams,et al.  The influence of soil texture and vegetation on soil moisture under rainout shelters in a semi-desert grassland , 2005 .

[9]  Markus Reichstein,et al.  Consequences of More Extreme Precipitation Regimes for Terrestrial Ecosystems , 2008 .

[10]  B. Wilcox,et al.  Soil and topographic controls on runoff generation from stepped landforms in the Edwards Plateau of Central Texas , 2007 .

[11]  G. Meehl,et al.  Climate extremes: observations, modeling, and impacts. , 2000, Science.

[12]  Stuart P. Hardegree,et al.  Runoff and Erosion After Cutting Western Juniper , 2007 .

[13]  Jake F. Weltzin,et al.  Dynamics of transpiration and evaporation following a moisture pulse in semiarid grassland: A chamber-based isotope method for partitioning flux components , 2005 .

[14]  T. McKee,et al.  THE RELATIONSHIP OF DROUGHT FREQUENCY AND DURATION TO TIME SCALES , 1993 .

[15]  T. Meixner,et al.  Altered ecohydrologic response drives native shrub loss under conditions of elevated nitrogen deposition. , 2006, Journal of environmental quality.

[16]  Frederick B. Pierson,et al.  Impacts of wildfire on soil hydrological properties of steep sagebrush-steppe rangeland , 2002 .

[17]  J. Blair,et al.  Contingent productivity responses to more extreme rainfall regimes across a grassland biome , 2009 .

[18]  J. Blair,et al.  Productivity responses to altered rainfall patterns in a C4-dominated grassland , 2003, Oecologia.

[19]  W. H. Blackburn,et al.  Partitioning small scale spatial variability of runoff and erosion on sagebrush rangeland , 1994 .

[20]  J. Lacey,et al.  Influence of Spotted Knapweed (Centaurea maculosa) on Surface Runoff and Sediment Yield , 1989, Weed Technology.

[21]  Debra P. C. Peters,et al.  Long‐term data collection at USDA experimental sites for studies of ecohydrology , 2008 .

[22]  R. Seager,et al.  Model Projections of an Imminent Transition to a More Arid Climate in Southwestern North America , 2007, Science.

[23]  M. McClaran,et al.  SPREAD OF INTRODUCED LEHMANN LOVEGRASS ALONG A GRAZING INTENSITY GRADIENT , 1992 .

[24]  P. Vitousek,et al.  Biological invasions by exotic grasses, the grass/fire cycle, and global change , 1992 .

[25]  J. Ditomaso,et al.  Soil water dynamics differ among rangeland plant communities dominated by yellow starthistle (Centaurea solstitialis), annual grasses, or perennial grasses , 2004, Weed Science.

[26]  Christopher M. McGlone,et al.  The impact of a prescribed burn on introduced Lehmann lovegrass versus native vegetation in the northern Chihuahuan Desert , 2004 .

[27]  R. Scott,et al.  Soil evaporation response to Lehmann lovegrass (Eragrostis lehmanniana) invasion in a semiarid watershed , 2009 .

[28]  P. Alpert,et al.  Patterns of invasion within a grassland community , 2002 .

[29]  M. Nichols.  Measured Sediment Yield Rates From Semiarid Rangeland Watersheds , 2006 .

[30]  M. S. Moran,et al.  Assessing vegetation change temporally and spatially in southeastern Arizona , 2008 .

[31]  T. Keefer,et al.  Growing season ecosystem and leaf-level gas exchange of an exotic and native semiarid bunchgrass , 2010, Oecologia.

[32]  Jerry C. Ritchie,et al.  Patterns of Soil Erosion and Redeposition on Lucky Hills Watershed, Walnut Gulch Experimental Watershed, Arizona , 2005 .

[33]  D. Easterling,et al.  Observed variability and trends in extreme climate events: A brief review , 2000 .

[34]  H. Mooney,et al.  Disruption of ecosystem processes in western North America by invasive species , 2004 .

[35]  J. R. Simanton,et al.  Sediment yields from unit‐source semiarid watersheds at Walnut Gulch , 2007 .

[36]  Dawn M. Kaufman,et al.  Changes in grassland ecosystem function due to extreme rainfall events: implications for responses to climate change , 2008 .

[37]  Jeffry J. Stone,et al.  THE WALNUT GULCH RAINFALL SIMULATOR: A COMPUTER-CONTROLLED VARIABLE INTENSITY RAINFALL SIMULATOR , 2004 .

[38]  J. Ditomaso.  Invasive weeds in rangelands: Species, impacts, and management , 2000, Weed Science.

[39]  B. Roundy,et al.  Lehmann lovegrass in southeastern Arizona: Biomass production and disappearance , 1990 .

[40]  M. McClaran,et al.  Spread of introduced Lehmann lovegrass Eragrostis lehmanniana Nees. in Southern Arizona, USA , 1992 .

[41]  Corinne Le Quéré,et al.  Climate Change 2013: The Physical Science Basis , 2013 .

[42]  R. B. Jackson,et al.  ECOHYDROLOGICAL CONTROL OF DEEP DRAINAGE IN ARID AND SEMIARID REGIONS , 2005 .

[43]  F. Pierson,et al.  Spatial and temporal effects of wildfire on the hydrology of a steep rangeland watershed , 2001 .

[44]  W. R. Osterkamp,et al.  Geology, Soils, and Geomorphology of the Walnut Gulch Experimental Watershed, Tombstone, Arizona , 2008 .

[45]  T. McKee,et al.  Drought monitoring with multiple time scales , 1995 .