铁矿废弃地不同恢复模式土壤团聚体及碳、氮分布

Distriubution Characteristic of Soil Water-stable Aggregates,Soil Organic Carbon and Nitrogen from Different Restoration Modes in Abandon Area of Iron Mine

以大田县铁矿废弃地不同恢复模式:"撒播马尾松(Pinus massoniana)"(R1)、"工程措施+植草"(R2)和"工程措施+乔灌草"(R3),并选择未恢复的铁矿废弃地作为恢复的初始状态(R0)及周边未开矿的杉木(Cunninghamia lanceolata)林作为对照(CK)进行研究,分析不同恢复模式的土壤水稳性团聚体及碳、氮含量分布特征。结果表明:①R0模式水稳性团聚体主要集中在<0.25 mm。采用不同恢复模式后,<0.25 mm水稳性团聚体含量显著减少,>5 mm和2~5 mm径级的水稳性团聚体含量显著增加。②不同恢复模式土壤团聚体稳定性的变化趋势为:CK>R3>R2>R1>R0。③土壤有机碳和全氮含量随着土壤团聚体粒径的减少呈显著升高。④铁矿废弃地不同恢复模式土壤有机碳和全氮含量与>5 mm的水稳性团聚体含量显著正相关,而与<0.25 mm和0.5~1 mm显著负相关。

In this study,abandon area of iron mine from different restoration modes were selected as research object in Datian County,including″sowing Pinus massoniana seeds″(R1),″engineering measures+sowing grass seeds″(R2),″engineering measures+arbor-shrub-grass(R3)″,and selected unrestored abandon area of iron mine as initial recovery status(R0)and adjecent-unexploit Cunninghamia lanceolata forests as control(CK),distribution characteristic of water-stable aggregates,soil organic carbon and total nitrogen were studied.The result indicated that①water-stable aggregates in R0 mode mainly distributed<0.25 mm.After adopting different restoration modes,soil water-stable aggregates in<0.25 mm significantly decreased,and in>5 mm and 2~5 mm significantly increased.②The order of soil aggregates from different restoration modes:CK>R3>R2>R1>R0.③Soil organic carbon and nitrogen content significantly increased with decreasing of soil aggreagate fraction.④Soil organic carbon and total nitrogen from different restoration modes in abandon area of iron mine were significantly positive correlated with>5 mm water-stable aggregates,and were significantly negative with<0.25 mm and 0.5~1 mm water-stable aggregates.