福建省沙化土地地球化学评价及其方法研究  

Geochemical evaluation and related method of desertified land in Fujian Province,China

作　　者：王文俊 WANG Wen-Jun(Fujian Institute of Geological Survey,Fuzhou 350013,China)

机构地区：[1]福建省地质调查研究院,福建福州350013

出　　处：《物探与化探》2025年第2期479-489,共11页Geophysical and Geochemical Exploration

基　　金：中国地质调查局地质调查项目(DD20160321);福建省地勘基金地质科技创新提升项目(闽地地任[2022]25号)。

摘　　要：基于福建省1∶25万多目标区域地球化学调查所获得的表层土壤SiO_(2)、Al_(2)O_(3)、Fe_(2)O_(3)和有机质等高精度、高质量数据,以表层土壤为评价对象,首次采用地球化学手段,建立了福建省沙化土地地球化学评价方法,即建立了硅铝铁率(Saf)、碳硅比(K_(Si))及其综合指标值(Szh_f)的计算方法,并作为沙化土地地球化学评价指标,其值越大沙化程度越高,反之,沙化程度越低。据此统计了福建省沙化土地地球化学等级参数,划定了福建省沙化土地地球化学等级分布范围,旨在从土壤元素微观方面对福建省沙化土地现状进行评价,进而查明其分布特征。结果表明:福建省强沙化、中度沙化、轻度沙化、轻微沙化土地分布面积及其占福建省总面积的比例分别为39531 hm^(2)(0.326%)、65790 hm^(2)(0.542%)、103601 hm^(2)(0.853%)、360329 hm^(2)(2.968%),主要分布于闽江以南的沿海海岸带和龙岩市长汀县。实地验证表明:该评价方法科学、可靠,沙化土地等级界线划分准确,能客观、真实地反映福建省沙化土地分布状况。Based on high-precision,high-quality data on SiO_(2)、Al_(2)O_(3)、Fe_(2)O_(3),and organic matter in topsoils obtained from the 1∶250,000-scale multi-purpose regional geochemical survey in Fujian Province,this study assessed topsoils and,for the first time,established a geochemical method-based geochemical assessment system for desertified land in the province.Specifically,this system involves methods for calculating the silicon-aluminum-iron ratio(Saf),carbon-silicon ratio(K_(Si)),and their comprehensive index value(Szh_f),which serves as the indicator for assessing the degree of land desertification.Specifically,a higher Szh_f value indicates a higher degree of desertification,and vice versa.Furthermore,this study determined the statistics of geochemical classification parameters for desertified land in Fujian Province and delineated the distribution ranges of geochemical grades.This aims to assess the cur-rent status of desertified land in the province from the microscopic perspective of soil elements and to further ascertain the distribution characteristics of the land.The results indicate that the land with strong,moderate,slight,and very slight desertification in Fujian Province exhibits areas of 39531 hectares(0.326%),65,790 hectares(0.542%),103601 hectares(0.853%),and 360329 hectares(2.968%),respectively,primarily distributed along the coastal zone to the south of the Minjiang River and in Changting County of Longyan City.Field verification demonstrates that this evaluation method is scientific and reliable and yields accurate classification results of desertification grades,thus objectively reflecting the distribution status of desertified land in Fujian Province.

关 键 词：沙化土地 地球化学 方法研究 分布特征 福建 

分 类 号：X142[环境科学与工程—环境科学] X825