论文部分内容阅读
选择西班牙东南部地区的不同土壤类型单元，调查了半干旱条件下土地弃荒对土壤侵蚀的影响。所选研究地点分别为：耕地（裸露）、3a弃荒地（草本植物覆盖）、10a弃荒地（蒿属植物覆盖）、以及分别由半原生植被（针茅属）和原生植被（松属）覆盖的两个土壤类型单元。模拟降雨测量结果表明，土地弃荒后侵蚀和径流增加，但随后的侵蚀又由于植被的增加而减少。与其它土地利用方式相比，3a弃荒地的径流量（35％）和侵蚀率*[334g／(m2·h)]较高。耕作促进了降雨的入渗，大大地减少了径流和侵蚀率。在针茅和蒿属植被覆盖下，植被覆盖样地的状况因渗透率高而非常稳定（降雨入渗率为100％）。松属植物的覆盖状况最好，但是由于疏水层的形成引起了径流系数（14％）和侵蚀速率［2g／(m2·h)］的提高。在干旱和过牧条件下，土地弃荒似乎促进了土壤退化，从而降低了入渗能力（从55mm／h降到19mm／h），增加了侵蚀速率[从O增加到334g／（m2／·h）]。10a弃荒地和半原生与原生植物覆盖下的土地，样地状况非常稳定，几乎不产生径流和侵蚀。径流和侵蚀的分配和植被的空间分布有直接关系。植被覆盖在开垦后会迅速缩小，而在弃荒后其空间差异会相应增加，随着油松林的形成，植被恢复到顶极阶段，植被覆盖、径流和侵蚀率表现?
Different soil types units in the southeastern part of Spain were selected to investigate the effects of abandoned land on soil erosion under semi-arid conditions. The study sites were selected as arable land (nudity), 3a wasteland (herbaceous plant cover), 10a wasteland (Artemisia plant cover), and semi-native vegetation (Stipa) and native vegetation Of two soil type units. Simulated rainfall measurements showed that the erosion and runoff increased after abandoned land, but the subsequent erosion was reduced due to the increase of vegetation. Compared with other land use patterns, runoff volume (35%) and erosion rate * [334g / (m2 · h)] in the abandoned land on 3a were higher. Farming promotes rainfall infiltration and greatly reduces runoff and erosion rates. Under the cover of Artemisia and Artemisia, vegetation cover is highly stable due to its high permeability (rainfall infiltration rate is 100%). Pinus covered the best, but the increase of runoff coefficient (14%) and erosion rate [2g / (m2 · h)] resulted from the formation of hydrophobic layer. Land abandonment appears to promote soil degradation under drought and overgrazing conditions, thereby reducing infiltration capacity (from 55 to 19 mm / h) and increasing erosion rates [from O to 334 g / (m2 / · h)]. 10a Abandoned and semi-native and native plant-covered lands, the plots are very stable with very few runoff and erosion. The distribution of runoff and erosion is directly related to the spatial distribution of vegetation. Vegetation cover will rapidly decrease after reclamation, but its spatial difference will be correspondingly increased after abandonment. With the formation of Pinus tabulaeformis forest, the vegetation is restored to the top stage, the vegetation coverage, runoff and erosion rate show?