以黄土高原地区典型流域人工生态林为研究对象,以土壤有机质和主要营养元素的理化特性为评价指标,研究了不同人工生态林对林地土壤营养元素含量的影响。结果表明,造林后侧柏幼龄林有机碳、全氮和水解氮质量分数均下降,降低率分别为45.73%、30.00%和34.57%,全磷、全钾质量分数分别降低了4.41%和5.61%,但磷、钾的速效成分较先前提高了96.04%和10.71%;刺槐幼龄林0<土壤深度h≤10 cm有机碳质量分数有明显的上升,10 cm
By reviewing the development of wetlands used for wastewater treatment both in China and other countries, the definition and classification of wetlands for wastewater treatment are put forward and the guiding principle in the construction of wetlands for wastewater treatment is discussed in this paper. In view of the process of wastewater treatment of the wetlands, appropriate landscape structure of wetlands used for wastewater treatment is proposed which includes three sections as pre-treatment, wetlands and posttreatment. The discussion as well as conclusion is made upon the approaches of landscape construction of these three parts.