Self‐Organization of Vegetation in Arid Ecosystems

Scientists are still searching for possible unifying mechanisms explain this range of spatial patterns (Tongway Ludwig 2001), and an important question of this research whether this range is the result of preexisting heterogeneity, the result of spatial selforganization, both (Klausmeier 1999; Couteron and 2001; HilleRisLambers et al. 2001; Von Hardenberg al. 2001). Here, we contribute to the ongoing debate vegetation pattern formation in arid ecosystems presenting novel, spatially explicit model analyses and , extending on the work of HilleRisLambers et al. (2001). Our results show that these different vegetation observed in arid ecosystems might all be the result spatial self-organization, caused by one single mechanism: infiltrates faster into vegetated ground than bare soil, leading to net displacement of surface water vegetated patches. This model differs from earlier model (Klausmeier 1999; Couteron and Lejeune 2001; et al. 2001; Von Hardenberg et al. 2001) primarily in two ways: it is fully mechanistic, and it treats lateral flow of water above and below the soil as separate, independent, variables. Although the current greatly simplifies the biophysics of arid systems, it reproduce the whole range of distinctive vegetation as observed in arid ecosystems, indicating that proposed mechanism might be generally applicable. further show that self-organized vegetation patterns persist far into regions of high aridity, where plants become extinct if homogeneously distributed, to the importance of this mechanism for maintaining of arid ecosystems (Noy-Meir 1973). analyses are based on the model first developed in et al. (2001)