【作者】 张晓红；

【导师】 霍习良；

【作者基本信息】 河北农业大学 ， 土壤学， 2002， 硕士

【摘要】 耕地资源是人类赖以生存的基础，耕地的可持续利用研究越来越重要，耕地土产力更新能力则是衡量耕地利用系统持续性的前提标准。本研究通过对土壤磷素地理平衡点进行指标选取和利用，用系统的观点揭示土壤磷素循环的过程及其更新能力，为耕地磷素生产力更新能力评价、耕地磷素系统的可持续管理提供了一些依据和方法。 土壤磷素地理平衡点指在特定的地理生物气候背景下，土壤磷素系统循环达到相对稳定平衡时的量化指标的数量水平，它的指标选取和求取方法应根据研究目的需要来确定。本研究根据代表性原则、灵敏性原则、稳定性原则和可度量原则，选定Ca₂-P作为雄县土壤磷素地理平衡点的描述指标，根据灰色系统预测理论，用数学求极限的方法，得雄县土壤磷素内源地理平衡点（CK处理）为3．2mg／kg，-P、1／2P（P₂O_s112．5kg／hm²）和全P处理（P₂O₅225kg／hm²）的土壤磷素外源地理平衡点分别为3．6mg／kg、8．6mg／kg和14．2mg／kg。 利用模糊数学隶属函数S型模型，把雄县土壤磷素外源、内源地理平衡点分别作为上下两个阈值，对该土壤磷素系统更新状况和磷素肥力进行评价，全P处理土壤磷素系统更新状况最佳，磷素肥力水平最高，CK、-P处理磷素肥力水平最低，土壤磷素系统更新状况最差，1／2P处理居中。应用土壤磷素外源更新系数进行耕地磷素持续性管理评价，1／2P处理是可持续性施肥战略的最佳方案。更多还原

【Abstract】 Cultivated land resource is the foundation of mankind’s survival, and study on sustainable cultivated land use is coming to be the focus of international research.. The renew-ability of cultivated land’s productivity is the first standard to evaluate its use-system’s sustainability. In this paper, some basses and methods are established for these evaluations by selecting proper index and using the geographical point of soil phosphorus equilibrium.The geographical point of soil phosphorus equilibrium refers to some quantitative characters of soil phosphorus system when its cycle becomes steady relatively in certain geographical, biological and climatic backgrounds. Its index and seeking method are determined differently in different studies. This paper chose Ca^-P as the index, based on its sensitiveness, stability, representatively and measurability: figured out the endogenesis geographical point of soil phosphorus equilibrium(of CK treat) as 3.2mg/kg, the exogenous geographical points of soil phosphorus equilibrium of-P, 1/2P (P2O5112.5kg/hm:) and complete P ( P2O5225kg/ hm2) as 3.6 mg/kg,8.6 mg/kg, and 14.2 mg/kg respectively.Using endogenesis and exogenous geographical points of soil phosphorus equilibrium as the two turning points in the S-type membership function, based on fuzzy mathematics, to evaluate the renewing status and fertility of Xiongxian country’s soil phosphorus system. The results are that complete P treat is the best, CK and -P are in the lowest, 1/2P mediates. For the sustainable fertilization strategy, 1/2P is the best scheme, according to the evaluation of various treatments’ exogenous renewing coefficient of soil phosphorus.更多还原