Ecohydrological interactions within banded vegetation in the northeastern Chihuahuan Desert, USA

Abstract

Landscape patterns, consisting of alternating densely vegetated bands and sparsely vegetated interbands, occur in semi-arid and arid regions of Africa, Asia, Australia and North America. The structure of vegetation patterns has been well documented, but a wide array of underlying environmental factors and ecological processes have been suggested, with no consensus regarding the genesis and persistence of these patterns. The purpose of this study was to assess ecohydrological interactions within this banded pattern by quantifying reallocation of rainfall and soil sediments. Even subtle redistribution impacted plant biomass production and species composition. Although runoff losses from interbands accounted for only 4% total rainfall, reallocation supported tree species and bunchgrasses that would not be sustained if precipitation were evenly distributed. Additionally, a rainfall threshold was identified. When storm totals exceeded 16 mm, even the densely vegetated bands were unable to capture all the rainfall and run-on from the upslope sodgrass interbands; a portion of the runoff from interbands flowed through the vegetated bands and continued downslope into the next interband.

History-dependent patterns of whole ecosystems

“…It occurs on gentle slopes in semi-arid regions, with stripes of grass, shrubs or trees running parallel to the contours, alternating with regions of bare ground Rietkerk et al, 2004). Banded vegetation occurs in many parts of the world, with particularly detailed data from subSaharan Africa (MacFadyen, 1950;Couteron et al, 2000), Australia (Dunkerley and Brown, 2002;Berg and Dunkerley, 2004), and Mexico/South-Western USA (Montañ a, 1992;McDonald et al, 2009). Typical wavelengths are about 1 km for trees and shrubs, with shorter wavelengths observed for grasses.…”

Local properties of patterned vegetation: quantifying endogenous and exogenous effects

“…Our site, located near Fort Stockton, TX, USA [43], was selected because it exhibits vegetation bands and also offers several characteristics that facilitate studies of covariation. First, the aerial photography covers a large region at a resolution (0.5 and 1 m) comparable to the diameter of perennial vegetation canopies, allowing for the observation of individual plants.…”

Pattern selection and hysteresis in the Rietkerk model for banded vegetation in semi-arid environments

“…It is now known that self-organized vegetation patterns are a characteristic feature of semi-arid regions in many parts of the world, particularly Africa [2,3], Australia [4,5] and North America [2,6,7]. On slopes, these patterns consist of stripes running parallel to the contours [8 -11].…”