关键词: 土壤干层, 土壤水分, 陕北黄土高原, 刺槐, 分布

Abstract: The rapid development of urbanization brings large volume of waste water to the environment, and its disturbances to natural ecosystem may break the structure and the balance of original ecosystems. Much attention has been paid on the resulted environmental effects, but how to restore a healthy river course system is still lacking scientific methodology. In this paper, the disturbance types and characteristics of urbanization on river course system, the key processes affecting river course system health, and related ecological restoration principles and approaches were elaborated. In general, there are three characteristics of the disturbances on river course system, i.e., structural fixation, shape regulation, and function simplification. The key processes affecting river course system health are the stoppage of substance exchange path, the destruction of wildlife habitat, and the imbalance of river eco-hydrological processes. Following six principles have to be followed when restoring river course system, i.e., 1) nature-based principle, 2) key function-steered principle, 3) spatial and temporal scaling principle, 4) consideration of ecological circulation and balance, 5) public participation of stakeholders, and 6) optimization of comprehensive benefits. The development directions, approaches, and spatiotemporal scale issues related to the ecological restoration of river course system were analyzed.

Key words: Soil dry layer, Soil moisture, North Shaanxi Loess Plateau, Robinnia pseudoscacia, Distribution