The potential roles of biological soil crusts in dryland hydrologic cycles
The potential roles of biological soil crusts in dryland hydrologic cycles
复制标题
DOI：
10.1002/hyp.6325
复制
发表时间：
2006-10-15
影响因子：
3.2
通讯作者：
Belnap, Jayne
中科院分区：
文献类型：
--
作者：
Belnap, Jayne
生物土壤结皮是世界上许多旱地的主要生物覆盖层。它们具有许多可以影响当地水文循环的不同方面的特征，包括土壤孔隙度、吸收率、粗糙度、团聚体稳定性、质地、孔隙形成和保水性。生物土壤结皮对这些因子的影响取决于其内部和外部结构，而这些结构随气候、土壤和扰动历史而变化。本文介绍了不同类型的生物土壤结皮，讨论了结皮类型如何可能影响水文循环的各个方面，并回顾了世界各地不同旱地生物结皮对沉积物产生和水渗透与径流的影响的已知和未知情况。大多数关于生物土壤结皮对当地水文影响的研究都是通过比较未受干扰的地点和研究人员最近扰动的地点来完成的。不幸的是，这大大复杂化了对结果的解释。施加干扰改变许多土壤特性，如土壤质地，粗糙度，团聚体的稳定性，物理结皮，孔隙度和体积密度的方式，不一定是相同的，如果结壳不是自然存在的。结合起来，这些研究表明，生物结皮如何影响水的渗透或径流的协议很少。然而，当研究按生物结皮类型分开，并利用这些类型之间自然存在的差异时，结果表明，极端干旱地区的生物结皮减少了渗透，增加了径流，在干旱和地区具有混合效应，在半干旱凉爽和寒冷的旱地增加了渗透，减少了径流。然而，在就生物结壳如何影响渗透和径流作出广泛的概括之前，还需要进行更多的研究。我们特别需要控制次表层土壤特征的研究，如体积密度、微孔和大孔以及生物结皮结构。与生物结壳对区域间渗透和径流的混合影响不同，几乎所有研究都表明，无论结壳或旱地类型如何，生物结壳都会减少沉积物的产生。出版社：John Wiley & Sons，Ltd.
Biological soil crusts (BSCs) are the dominant living cover in many drylands of the world. They possess many features that can influence different aspects of local hydrologic cycles, including soil porosity, absorptivity, roughness, aggregate stability, texture, pore formation, and water retention. The influence of biological soil crusts on these factors depends on their internal and external structure, which varies with climate, soil, and disturbance history. This paper presents the different types of biological soil crusts, discusses how crust type likely influences various aspects of the hydrologic cycle, and reviews what is known and not known about the influence of biological crusts on sediment production and water infiltration versus runoff in various drylands around the world. Most studies examining the effect of biological soil crusts on local hydrology are done by comparing undisturbed sites with those recently disturbed by the researchers. Unfortunately, this greatly complicates interpretation of the results. Applied disturbances alter many soil features such as soil texture, roughness, aggregate stability, physical crusting, porosity, and bulk density in ways that would not necessarily be the same if crusts were not naturally present. Combined, these studies show little agreement on how biological crusts affect water infiltration or runoff. However, when studies are separated by biological crust type and utilize naturally occurring differences among these types, results indicate that biological crusts in hyperarid regions reduce infiltration and increase runoff, have mixed effects in and regions, and increase infiltration and reduce runoff in semiarid cool and cold drylands. However, more studies are needed before broad generalizations can be made on how biological crusts affect infiltration and runoff. We especially need studies that control for sub-surface soil features such as bulk density, micro- and macropores, and biological crust structure. Unlike the mixed effects of biological crusts on infiltration and runoff among regions, almost all studies show that biological crusts reduce sediment production, regardless of crust or dryland type. Published in 2006 by John Wiley & Sons, Ltd.