鄱阳湖沙地植被恢复年限和结构配置对土壤特性的影响

Effects of vegetation restoration age and structure types on soil properties of sandy land

比较了不同恢复年龄和不同恢复结构类型对南方江西沙地土壤有机质(SOC)、全氮(TN)、全磷(TP)、全钾(TK)、碱解氮(AHN)、速效磷(AP)、速效钾(AK)等土壤化学性质影响,以及对土壤含水量(SMC)和容重(SBD)等物理性质影响。结果表明近成熟林(25.85%)和乔+灌+草恢复结构下(30.66%)的土壤水分含量显著高于裸沙地对照的8.09%和14.98%。不同恢复年龄和恢复结构类型对土壤有机碳、总氮、总氮、氮、磷、速效氮均有显著影响;随着恢复年龄的增加,沙地土壤养分除碱解氮减少外,其他养分含量均呈现增加的变化趋势。此外,不同植被恢复结构类型中,沙地土壤各养分含量均表现出增加的变化趋势。不同恢复年龄之间沙地0~20cm土层的有机质、全氮、全磷、有效磷和速效钾有显著差异。不同植被恢复结构之间沙地0~20cm土层有机质、全氮、全磷、碱解氮、有效磷和速效钾有显著差异。两种不同恢复模式都能显著提升南方沙地土壤化学和物理特性,说明这两种植被恢复模式对未来气候变化条件下南方沙地的恢复是有效的。

Vegetation restoration is an important and effective approach to constraining sand hazards,and comprehensive prevention and control of sandy land desertification.The soil is seriously suffering from the desertification because of the changes of environmental factors,frequent anthropogenic activity,excessive exploitation and unreasonable use of land resources in Jiangxi Province of southern China.In this study,we compared the soil chemical properties,including soil organic matter(SOC),total nitrogen(TN),total phosphorus(TP),total potassium(TK),alkali hydrolyzable nitrogen(AHN),available phosphorus(AP)and available potassium(AK),and physical properties including soil moisture content(SMC)and soil bulk density(SBD)between different restoration age(40-yr,20-yr,10-yr and bare control(BC-1))and restoration structure types(Tree+shrub+grass(TSG),Tree+grass(TG),pure tree(PT)and bare control(BC-2)).The results show that soil moisture content in restoration age 40-yr stand(25.85%)and TSG(30.66%)was significantly higher than BC-1(8.09%)and BC-2(14.98%).Both restoration age and structure types had a significant effect on SOC,TN,TP,AHN,AP and AK.With the increasing restoration age,the soil nutrients of sandy land were increased except for the reduced AHN.In addition,the restoration structural types from PT,TG to TSG,all nutrients of sandy land soil were increased.Restoration age had a significant effect on SOC,TN,TP,AP and AK in 0-20 cm soil layer of sandy land.Restoration structural types had a significant effect on SOC,TN,TP,AHN,AP and AK in 0-20 cm soil layer of sandy land.This result indicates that the restoration age and structure types significantly enhance soil chemical and physical properties,which indicates that the two vegetation restoration patterns are effective in the recovery of sandy land under future climatic change in Jiangxi Province of southern China.