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首页> 外文期刊>Environmental Conservation >Small wetlands lost: a biological conservation hazard in Mediterranean landscapes
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Small wetlands lost: a biological conservation hazard in Mediterranean landscapes

机译：小湿地消失：地中海景观中的生物保护危害

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摘要

In Spain, it is estimated that 60% of wetlands have disappeared in the last 50 years. The present study aimed to describe the relationships between loss of wetlands and land-use change in Azuaga County, Central-western Iberian Peninsula where during the period 1896-1996, 94% of the original wetlands disappeared. Forest, scrub, holm oak dehesas and olive groves have become fragmented or disappeared completely, having been substituted by eucalyptus plantations in areas of low productivity and by dry cultivation of herbaceous crops, mainly cereals, in more productive areas. These substitutions have resulted in a homogeneous, coarse-grained landscape with low diversity and high dominance. The type of land-use has depended on the evolution of demographic processes, with high human immigration rates toward the end of the nineteenth century and beginning of the twentieth century, and high emigration rates during the 1960s and 1970s. The mechanization of agriculture and transition from closed to market economy in the second half of the twentieth century also played an essential role in the landscape changes described.
机译：据估计，在过去的50年中，西班牙有60％的湿地消失了。本研究旨在描述中西部伊比利亚半岛阿苏阿加县湿地流失与土地利用变化之间的关系，该地区在1896-1996年期间消失了94％的原始湿地。森林，灌木丛，圣栎橡树的德赫萨斯和橄榄树林已经变得支离破碎或完全消失，在生产力低下的地区被桉树种植所替代，在生产力更高的地区被草本植物（主要是谷物）的干法栽培所取代。这些替代导致了具有低多样性和高支配性的均质，粗粒度景观。土地利用的类型取决于人口统计过程的演变，直到19世纪末和20世纪初，人类的移民率很高，而1960年代和1970年代的移民率却很高。在二十世纪下半叶，农业机械化和从封闭经济向市场经济的转变在描述的景观变化中也发挥了重要作用。

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