西安临潼人工林土壤干化与恢复研究

通过野外调查和室内测定,本文研究了西安临潼人工林下0-6m土壤含水量和土壤干层的变化。结果表明,临潼14龄杨树林和16龄梧桐树林下150-350cm之间土层的含水量分别为8.7%和9.0%。按土壤干层划分标准(含水量<10%),这已属于发育弱的土壤干层,说明西安地区人工林下有土壤干层存在。而在丰水年中,杨树林和梧桐树林下原有的土壤干层带水分含量增加到21.6%和21.7%,土壤干层消失,说明在降水量增加的条件下,西安地区发育弱的土壤干层可以得到恢复,人工林能够正常生长。由此推断,西安及其降水量与其类似的其他地区可以种植一些高大乔木或果树经济林。在土壤干层发育严重的黄土高原北部地区不适于广泛造林,可以优先考虑发展疏林和森林草原植被。

Research on Soil Dryness and the Recovery Below Artificial Forest in Lintong of Xi'an

Through field investigation and laboratory tests,the water content changes of soil dry layer of 0-6m under the artificial forest in Lintong of Xi'an were studied in this research.The results show that the soil water content among150-350cm under the poplar trees of 14 years and the Chinese parasol trees of 16 years are respectively 8.7% and 9.0%.According to standard of dividing of soil dry layer(where water content smaller than 10%),this belong to weakly developed soil dry layers,which prove that there exist the soil dry layer under the artificial forest in Xi'an.But in the year that has abundant precipitation,the water contents of soil dry layer already existing under poplar forest and Chinese parasol tree have risen to 21.6% and 21.7%,the soil dry layer has disappeared,which prove that the precipitation increases,the soil dry layer can be resumed,and the artificial forest can grow normally in Xi'an area.Therefore inference,some tall and big arbors or the fruit trees can be planted in Xi'an and other areas with same precipitation.It is not suitable for afforesting extensively in the areas such as northern territory of loess plateau that develop serious soil dry layer in the soil,but we can pay the preferential attention to developing the sparse woods and forest-grassland vegetation.