基于土壤功能与胁迫的耕地土壤健康评价方法

Farmland Soil Health Evaluation Method Based on Soil Function and Soil Threat

基于功能性土壤管理理论,针对初级生产力、养分供给与循环、生物多样性供给、水净化与调节、碳封存与调节5种功能选取评价指标,通过识别水田、水浇地和旱地对不同土壤功能的供给和需求关系,构建土壤功能供需判别矩阵,并叠加重金属污染胁迫因素,评价耕地土壤的健康状况,从而实现了基于土壤功能与胁迫的耕地土壤健康评价。在河南省温县进行了评价方法的适用性研究,结果表明:温县5种土壤功能供需空间格局基本呈现由南向北逐渐递增的趋势,以青峰岭为界,中北部土壤功能的供需处于盈余状态,而南部区域处于失衡状态;土壤健康等级交错分布,亚健康面积占比最大,为44.4%,健康土壤零散分布在黄庄镇、番田镇、武德镇和祥云镇;土壤质地、土体构型、土壤养分、土壤生物活性和重金属污染胁迫是导致耕地土壤健康空间分异的主要因素。本研究可在理论上丰富土壤健康评价方法体系,在实践上促进耕地资源可持续利用与管理。

Farmland soil is the foundation of national food security,and the management and protection of soil health is crucial to achieve sustainable development goals.Based on the theory of functional soil management,selected evaluation indicators for the five functions of primary productivity,provision and cycling of nutrients,provision of functional and intrinsic biodiversity,water purification and regulation,and carbon sequestration and regulation,by identifying paddy land,irrigated land and dry land for different soils.The relationship between the supply and demand of functions was identified,a soil function supply and demand discriminant matrix was constructed,and the heavy metal pollution threat factors were overlied,the farmland soil health was evaluated,and the spatial mapping of evaluation indicator—soil function/threat—soil health was realized.A study on the applicability of the evaluation method was carried out in Wen County,Henan Province.The results showed that the spatial pattern of the supply and demand of the five soil functions in Wen County basically showed a trend of gradually increasing from south to north,with Qingfengling as the boundary,the supply and demand of soil functions in the central and northern regions were in surplus,while the supply and demand in the southern region were in an imbalanced state.Staggered distribution of soil health grades,the sub-health area accounted for the largest proportion,accounting for 44.4%.Healthy soil was scattered in Huangzhuang Town,Fantian Town,Wude Town,and Xiangyun Town.Soil texture,soil structure,soil nutrients,soil biological activity and heavy metal pollution threat were the main factors for the spatial differentiation of soil health.This research can enrich the soil health evaluation method system theoretically,and promote the sustainable utilization and management of farmland resources in practice.