额济纳三角洲土壤养分特征分析

选择黑河下游额济纳旗为研究区,采用野外调查和室内分析相结合的方法,研究其土壤养分特征.通过对2003年额济纳土壤样品的分析得出:土壤pH值在7.97～9.35之间,呈碱性;全N、全P、全K,pH值比较集中,速效N、速效P、速效K和有机质的含量比较分散,差异大;对土壤养分成分进行了主成分分析,第一、第二主分量的累计贡献率达到73.65%.第一主成分代表土壤综合养分水平;第二主成分则主要反映土壤的K肥和速效P水平.通过对主成分低维聚类分析,将研究区的土壤大致划分为4类,并针对不同类型土壤分别提出了改善措施.

Analysis on Soil Nutrients in the Erjina Delta

As one of the aridest regions in China, the study area, Erjina Banner of Inner Mongolia Autonomous Region is located in the lower reaches of the Heihe River, its western, southwestern and northern sides are surrounded by mountains, and its total area is 1. 161 05 km^2, in which the area of oases is 3 116 km^2 and occupies 5.01%. In the banner it belongs to the typical continental arid climate, the annual precipitation is 39.8 mm only, but the annual evaporation is as high as 3 504 mm, and rainfall occurs mainly during the period from June to September and occupies 70 % - 80 % of annual precipitation. The vegetation mainly composed of Populus euphratica, Elaeagnus angusti folia , Tarnarix spp. , Haloxylon ammodendron, Achnatherum splendens, and Phragmites communis as well as Sopbora alorides, Lycium ruthenicum and Glycyrrhiza uralensis is distributed in the valleys, zones around the lakes and terraces, the vegetation coverage is about 30%, some fragmentary pieces of Reaumaria soongorica, Alhagi pseudoalhagi, Peganum harmala, etc. , are also distributed, and the vegetation coverage is less than 5%. In this paper, the soil nutrients in the study area are researched based on the filed-investigated data and the analyzed results in laboratory. The results show that the pH values of soils vary in a range of 7.97-9.35, the total N, P, K and pH values are distributed in concentrative way, but the available N, P, K and organic matter are dispersedly distributed; the results of principal component analysis of soil nutri- ents reveal that the contribution ratio of the first and second principal components is 73.65 % ; the first principal component reflect the synthetic nutrient level of soil, and the second principal component reflect the soil K and available P. Moreover, some measures are put forward form improving soil in the study area.