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为阐明黄河三角洲不同人工林类型对盐碱化土壤碳(C)氮(N)磷(P)含量及生态化学计量特征的影响,选取刺槐、臭椿、杨树、白蜡、榆树、国槐和柽柳等7种典型人工林为研究对象,运用模糊数学隶属函数法综合评价林型对土壤营养和化学计量特征的影响。结果表明:黄河三角洲地区7种林型土壤C、N含量处于全国土壤平均含量的最低水平,P含量居中等水平。各林型土壤表层C、N含量较高,P含量从上至下分布规律不同,分别呈逆向、“V”型和倒“V”型分布。臭椿林土壤C、N、P元素平均含量最高,柽柳林土壤最低,前者分别是后者的1.5、1.7和1.2倍。7种人工林土壤N∶P平均值为0.76,远远低于全球平均水平(5.9)和我国平均水平(3.9),表明该区域人工林受到严重的土壤N限制。综合评价对林地土壤营养、土壤物理性质和化学计量改良作用最好的是国槐林,改良作用最差的为白蜡林。建议在该区域优先选择国槐改良盐碱化土壤,其次为杨树和榆树。
In order to elucidate the effects of plantations on carbon (C), nitrogen (N) and phosphorus (P) contents in ecologically salinized soils of the Yellow River Delta, we selected Robinia pseudoacacia, Ailanthus altissima, Populus, Ash, Ulmus, Sophora and Tamarix And other seven kinds of typical plantations were used as research objects. The fuzzy mathematics membership function method was used to evaluate the effects of forest types on soil nutrition and stoichiometry. The results showed that the content of C and N in the seven forest soils in the Yellow River Delta was at the lowest level of the national soil average content and the P content was at the middle level. The contents of C and N in the topsoils of the forest types were higher, and the distribution of P content was different from top to bottom. They were reverse, “V” type and inverted “V” type. Ailanthus altissima soil C, N, P elements of the highest average content, Tamarix its lowest soil, the former were the latter 1.5,1.7 and 1.2 times. The soil N: P average of 7 plantations was 0.76, far below the global average (5.9) and China’s average (3.9), indicating that the plantation forests in this area were severely limited by soil N. Comprehensive evaluation of forest soil nutrients, soil physical properties and stoichiometry is best to improve the role of Sophora japonica, the worst improvement for the white wax forest. Proposed in the region preferred Sophora japonica improved salinization soil, followed by poplar and elm.