|Title||Location, location, location: The influence of plant neighborhood configuration on grass-shrub interactions|
|Publication Type||Conference Paper|
|Year of Publication||2015|
|Authors||Pierce N, Archer SR, Bestelmeyer BT|
|Conference Name||100th Annual Meeting of the Ecological Society of America (ESA)|
|ARIS Log Number||319945|
State transition from perennial grassland to shrubland or woodland is often synonymous with land degradation and desertification in arid and semiarid ecosystems. These physiognomic transitions markedly alter rates and dynamics of ecological processes and the ability of ecosystems to provide services of value to society. Land managers and other stakeholders could benefit from research designed to identify vegetative structural properties that forecast when ecological sites might be at risk for state changes. We sought to determine such indicators via removal experiments conducted along an extant Bouteloua eriopoda-to-Prosopis glandulosa encroachment gradient at the Jornada Basin LTER site in the northern Chihuahuan Desert. Ninety plots centered upon B. eriopoda patches were established along the grassland-to-shrubland gradient. The size of and distance to all P. glandulosa individuals within a 5 m radius was recorded and aboveground shrub biomass was estimated using site- and species-specific allometric regression (R2 = 0.89). Peak season B. eriopoda biomass was quantified in 2010. P. glandulosa shrubs within 5 m of half of grass plots (n=45) were then killed via foliar herbicide in early summer 2011. B. eriopodabiomass was again quantified at the end of the subsequent growing seasons.