Gully erosion and environmental change: importance and research needs
Gully erosion and environmental change: importance and research needs
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DOI：
10.1016/s0341-8162(02)00143-1
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发表时间：
2003-01-01
期刊：
影响因子：
6.2
通讯作者：
Valentin, C
中科院分区：
文献类型：
--
作者：
Poesen, J;Nachtergaele, J;Valentin, C
评估气候尤其是土地利用变化对水蚀土壤速率的影响是许多国家和国际研究项目的目标。然而，在过去几十年中，大多数有关水蚀土壤的研究都集中在地块（径流）尺度上发生的片蚀（细沟间侵蚀）和细沟侵蚀过程。在更大空间尺度上进行的沟蚀研究相对较少。近期研究表明：（1）沟蚀在一系列环境中是一个重要的泥沙来源；（2）沟壑是将径流和泥沙从高地输送到谷底和永久性河道的有效纽带，在那里它们加剧了水蚀的场外影响。换句话说，一旦沟壑形成，它们就会增加景观的连通性。许多农业用地径流对河道和财产造成损害（泥沙和化学物质）的案例都与（临时性）沟蚀有关。因此，有必要对沟蚀进行监测、实验和建模研究，以此作为预测环境变化（气候和土地利用变化）对沟蚀速率影响的基础。在这方面，可以确定各种研究问题。其中最重要的问题如下：
（1）在不同的时空尺度以及不同的气候和土地利用条件下，沟蚀对总体土壤流失和泥沙产生的贡献是多少？
（2）在不同的时空尺度上，对各种类型沟壑的形成和发展进行监测和实验研究的合适测量技术是什么？
（3）我们能否根据水流动力学、降雨、地形、土壤和土地利用等方面，确定不同环境中沟壑形成、发展和填充的关键阈值？
（4）沟蚀如何与水文过程以及其他土壤退化过程相互作用？
（5）合适的沟蚀模型是什么，能够预测（a）不同时空尺度上的侵蚀速率以及（b）沟壑发展对水文、泥沙产量和景观演变的影响？
（6）有效的沟壑预防和沟壑控制措施是什么？从沟壑侵蚀控制项目的失败和成功中可以学到什么？
如果我们想提高对环境变化对沟蚀影响的认识，首先就需要回答这些问题。本文通过回顾来自不同环境的近期实例，强调了其中一些问题。（C）2003爱思唯尔科学出版社。保留所有权利。
Assessing the impacts of climatic and, in particular, land use changes on rates of soil erosion by water is the objective of many national and international research projects. However, over the last decades, most research dealing with soil erosion by water has concentrated on sheet (interrill) and rill erosion processes operating at the (runoff) plot scale. Relatively few studies have been conducted on gully erosion operating at larger spatial scales.Recent studies indicate that (1) gully erosion represents an important sediment source in a range of environments and (2) gullies are effective links for transferring runoff and sediment from uplands to valley bottoms and permanent channels where they aggravate off site effects of water erosion. In other words, once gullies develop, they increase the connectivity in the landscape. Many cases of damage (sediment and chemical) to watercourses and properties by runoff from agricultural land relate to (ephemeral) gullying. Consequently, there is a need for monitoring, experimental and modelling studies of gully erosion as a basis for predicting the effects of environmental change (climatic and land use changes) on gully erosion rates.In this respect, various research questions can be identified. The most important ones are:(1) What is the contribution of gully erosion to overall soil loss and sediment production at various temporal and spatial scales and under different climatic and land use conditions?(2) What are appropriate measuring techniques for monitoring and experimental studies of the initiation and development of various gully types at various temporal and spatial scales?(3) Can we identify critical thresholds for the initiation, development and infilling of gullies in different environments in terms of flow hydraulics, rain, topography, soils and land use?(4) How does gully erosion interact with hydrological processes as well as with other soil degradation processes?(5) What are appropriate models of gully erosion, capable of predicting (a) erosion rates at various temporal and spatial scales and (b) the impact of gully development on hydrology, sediment yield and landscape evolution?(6) What are efficient gully prevention and gully control measures? What can be learned from failures and successes of gully erosion control programmes?These questions need to be answered first if we want to improve our insights into the impacts of environmental change on gully erosion. This paper highlights some of these issues by reviewing recent examples taken from various environments. (C) 2003 Elsevier Science B.V. All rights reserved.