POTENTIAL WATER STORAGE CAPACITY OF THE ROOT ZONE OF CULTURAL PHYTOCOENOSES IN THE ZAHORSKA NIZINA LOWLAND -A QUANTIFICATION OF SOIL ACCUMULATION FUNCTION

摘要

The paper deals with estimation of potential water storage capacity of the root zone of cultural phytocoenoses and its quantification as a property of soil accumulation function (AFS). A progressive spatial and pedo-transfer approach of estimation was used in the region of the Zahorsk? nfzina lowland. Potential reserves of water for agrocoenoses (crops, permanent cultural grassy vegetation), designated as the potential water storage capacity, and relevant hydrolimits (field water capacity, point of decreased water availability, wilting point) in the root zone of agricultural soils are presented as quantitative parameters for evaluation of AFS. Spatial presentation is processed by GIS for (i) particle size composition units (ii) genetic soil units and (iii) pedo-ecological regions. Relevant output was derived from soil data of Complex Agricultural Soil Survey digital database (KPP DB) by using pedo-tranfer functions (Rosetta model). Water storage capacity represents maximum volume of long-term available water potentially present in the effective soil depth for cultural coenoses. Quantification and spatial estimation of AFS should be one of the basic steps for complex geoecological evaluation and delimitation of agricultural land considering drought-threat or groundwater pollution, prediction of soil erosion and some other important landscape-ecological factors.