Self-organization of vegetation in arid ecosystems
Self-organization of vegetation in arid ecosystems
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DOI：
10.1086/342078
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发表时间：
2002-10-01
影响因子：
2.9
通讯作者：
de Roos, AM
中科院分区：
文献类型：
--
作者：
Rietkerk, M;Boerlijst, MC;de Roos, AM
Am. Nat. 2002.第160卷，第160页。524-530. 2002年由芝加哥大学出版。0003-0147/2002/16004-0009 15美元。All rights reserved. ley et al. 1997; Aguiar and Sala 1999; Klausmeier 1999; Leprun 1999; Couteron and Lejeune 2001; Von哈登贝格et al. 2001）。在此，“干旱”一词是指旱季延长的环境，年潜在蒸发量超过年降雨量，植物生长受到水供应的限制。在干旱生态系统中观察到的植被与裸露土壤交替的两阶段镶嵌体在规模和形状上有所不同，这取决于坡度和降雨量。当坡度为！年平均降雨量200 ~ 550 mm，植被类型为直径5-20 m的点，植被带宽度10-50 m的小块（图1a），以及直径为5-20米的植被中有裸点的林隙格局（图1b; Bromley等，1997; Aguiar和Sala，1999; Ludwig等，1999 b; Valentin等，1999; Couteron和Lejeune，2001）。在干旱区坡度大于0.2%的山坡上，可观察到典型的规则带状植被格局，带宽在几十米范围内（Klausmeier 1999; Leprun 1999; Valentin et al. 1999;科学家们仍在寻找可能的统一机制来解释这一系列的空间模式（Tongway and Ludwig 2001），而这项研究的一个重要问题是，这一范围是先前存在的环境异质性的结果，空间自组织的结果，还是两者兼而有之（Klausmeier 1999; Couteron and Lejeune 2001; HilleRisLambers et al. 2001; Von哈登贝格et al. 2001）。在这里，我们有助于干旱生态系统中的植被格局形成的持续辩论，提出新的，空间上明确的模型分析和结果，延长HilleRisLambers等人的工作。（2001年）的第10页。我们的研究结果表明，在干旱生态系统中观察到的这些不同的植被格局可能都是空间自组织的结果，由一个单一的机制：水渗透到植被的地面比到裸露的土壤，导致地表水的净位移植被补丁。该模型不同于早期的模型结果（Klausmeier 1999; Couteron和Lejeune 2001; HilleRisLambers等人2001; Von哈登贝格等人2001）
Am. Nat. 2002. Vol. 160, pp. 524–530. 2002 by The University of Chicago. 0003-0147/2002/16004-0009 $15.00. All rights reserved. ley et al. 1997; Aguiar and Sala 1999; Klausmeier 1999; Leprun 1999; Couteron and Lejeune 2001; Von Hardenberg et al. 2001). Here, the term “arid” refers to environments characterized by an extended dry season, where yearly potential evaporation exceeds yearly rainfall, and where plant growth is limited by water availability. The two-phase mosaics of vegetation alternating with bare soil as observed in arid ecosystems differ in scale and shape, depending on slope gradient and rainfall. When slope gradient is! 0.2% and mean annual rainfall ranges from 200 to 550 mm yrJ1, observed vegetation patterns include spots with a diameter of 5–20 m, labyrinths with a vegetated band width of 10–50 m (fig. 1a), and gap patterns with bare spots in the vegetation with a diameter of 5–20 m (fig. 1b; Bromley et al. 1997; Aguiar and Sala 1999; Ludwig et al. 1999b; Valentin et al. 1999; Couteron and Lejeune 2001). On slopes steeper than 0.2% in arid regions, typical regular-banded vegetation patterns with a band width in the range of a few tens of meters are observed (Klausmeier 1999; Leprun 1999; Valentin et al. 1999; d’Herbes et al. 2001).Scientists are still searching for possible unifying mechanisms to explain this range of spatial patterns (Tongway and Ludwig 2001), and an important question of this research is whether this range is the result of preexisting environmental heterogeneity, the result of spatial selforganization, or both (Klausmeier 1999; Couteron and Lejeune 2001; HilleRisLambers et al. 2001; Von Hardenberg et al. 2001). Here, we contribute to the ongoing debate about vegetation pattern formation in arid ecosystems by presenting novel, spatially explicit model analyses and results, extending on the work of HilleRisLambers et al.(2001). Our results show that these different vegetation patterns observed in arid ecosystems might all be the result of spatial self-organization, caused by one single mechanism: water infiltrates faster into vegetated ground than into bare soil, leading to net displacement of surface water to vegetated patches. This model differs from earlier model results (Klausmeier 1999; Couteron and Lejeune 2001; HilleRisLambers et al. 2001; Von Hardenberg et al. 2001)