Yair A, Shachak M
Institue of Earth Sciences, The Hebrew University of Jerusalem, Israel.
Watershed Ecology Unit. Blaustein Institute for Desert Research, Ben Gurion University, Israel.
Oecologia. 1982 Sep;54(3):389-397. doi: 10.1007/BF00380008.
Little attention has been directed to the study of soil flow and the complex relationships among energy water and soil flow in terrestrial ecosystems. Soil plays an important role in arid ecosystems. After water soil is the second key factor in the development of an arid ecosystem since soil is the only part of the system capable of absorbing and storing water and nutrients during the hot and long summer period. The present work presents a case study of an ecological soil flow chain in an arid environment and analyses the relationship between this chain and the energy and water flow chains. The study was conducted at the Sde Boqer experiment site located in the northern Negev of Israel where average annual rainfall is 92 mn. Data collected during five consecutive years show that the soil movement process within the ecosystem studied cannot be considered as a purely physical phenomenon, but rather as a part of a complex system in which the burrowing and digging activity of Isopods and Porcupines plays an important role by providing disaggregated soil particles easy to remove by shallow flows. Although controlled by the spatial distribution of soil moisture the biological activity acts as a regulator of soil depth and thus of soil moisture. If this regulating role is deleted from the system a new ecosystem, more arid, can be expected to develop. It is therefore concluded that the study of state and flow variables of an arid ecosystem should consider altogether the water, soil, energy and mineral chains.
陆地生态系统中土壤流动以及能量、水和土壤流动之间的复杂关系一直很少受到关注。土壤在干旱生态系统中起着重要作用。在干旱生态系统的发展过程中，除了水之外，土壤是第二个关键因素，因为在漫长炎热的夏季，土壤是该系统中唯一能够吸收和储存水及养分的部分。本研究以干旱环境中的生态土壤流动链为例，分析了该链条与能量和水流链之间的关系。研究在以色列内盖夫北部的Sde Boqer实验场进行，该地区年平均降雨量为92毫米。连续五年收集的数据表明，所研究生态系统内的土壤运动过程不能被视为纯粹的物理现象，而应被视为一个复杂系统的一部分，在这个系统中，等足类动物和豪猪的挖掘活动通过提供易于被浅层水流带走的分散土壤颗粒发挥着重要作用。尽管受土壤湿度空间分布的控制，但生物活动是土壤深度以及土壤湿度的调节者。如果从该系统中去除这种调节作用，预计会形成一个更加干旱的新生态系统。因此得出结论，对干旱生态系统状态和流动变量的研究应综合考虑水、土壤、能量和矿物质链。
