金衢盆地退化红砂土在不同利用方式下肥力逆转特征

SOIL FERTILITY RESTORATION CHARACTERISTICS OF DEGRADED RED SANDSTONE SOILS IN THE JINQU BASIN UNDER DIFFERENT LAND USE SYSTEMS

以浙江省金衢盆地为例 ,探讨了我国南方山间盆地广泛分布的退化红砂土的特征 ,研究了退化红砂土在人为参与下土壤肥力的逆转及其与利用方式的关系 ,分析了各种利用方式下红砂土肥力性质的演变特征。

Red sandstone soils are derived from red sandstone rock,and distributed widely in many basins in tropical and subtropical regions of China.The long term irrational utilization and management,togerher with the hursh climatic conditions and the inherent fragility of the basin ecosystems,have caused severe degradation of the red sandstone soils,characterized by high acidity,low nutrients,and disturbed unbalanced ecosystem.In order to ameliorate degraded red sandstone soils and to restore their productivity,different patterns of land use have been tested to examine their effect on soil fertility evolution.The objectives of this paper are to evaluate the relationship between the soil fertility restoration and land use,and to explore effective ways to restore the degraded red sandstone soils. The result shows that the rate of the soil fertility restoration of degraded red sandstone soil varied considerably with land use patterns because of different input of nutrients,and organic matter,thus determinating the rate and direction of soil fertility evaluaton.Rational land use with appropriate input could improve soil fertility.The restoration rate of degraded red sandstone soils under different land use pattern was decreased in the order of paddy field>upland>friut garden and tea garden>forestland.The soil fertility is attained the most quickly when the soils have been used as paddy field and soil fertility is restored the most slowly if the soil is used as forestland and no nutrients and energy are input.