Fluvial adjustments to soil erosion and plant cover changes in the central spanish pyrenees
Fluvial adjustments to soil erosion and plant cover changes in the central spanish pyrenees
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DOI：
10.1111/j.1468-0459.2006.00293.x
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发表时间：
2006-10
期刊：
影响因子：
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通讯作者：
S. Beguerı́a;J. López‐Moreno;A. Gómez‐Villar;Virginia Rubio;N. Lana-Renault;J. García‐Ruiz
中科院分区：
文献类型：
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作者：
S. Beguerı́a;J. López‐Moreno;A. Gómez‐Villar;Virginia Rubio;N. Lana-Renault;J. García‐Ruiz
摘要。直到20世纪中叶，比利牛斯河的特点是辫状河道、不稳定的沉积结构和冲积平原几乎完全没有植物覆盖，这是由于山坡的高产沙量和频繁而强烈的洪水发生。这可能与强大的人口压力有关，包括陡坡的种植、频繁的火灾、森林砍伐和过度放牧。人口减少和农田废弃导致原有耕地的植物重新定植，导致径流和产沙量减少。因此，大多数比利牛斯河倾向于减少冲积平原的宽度，并以切割的、有点蜿蜒的模式取代辫状模式，这涉及到新的阶地水平的建设和河流坝的稳定。
ABSTRACT. Until the middle of the 20th century, Pyrenean rivers were characterized by braided channels, unstable sedimentary structures and an almost complete lack of plant cover in the alluvial plain, due to the high sediment yield in hillslopes and the occurrence of frequent and intense flooding. This was probably related to strong demographic pressures, including the cultivation of steep slopes, frequent fires, deforestation and overgrazing. Depopulation and farmland abandonment resulted in plant recolonization in formerly cultivated areas, causing a decrease in runoff and sediment yield. As a consequence, most Pyrenean rivers tend to reduce the width of the alluvial plain and to replace the braided pattern with an incised, somewhat meandering pattern, involving the construction of new terrace levels and the stabilization of fluvial bars.