沿海经济发达区种植结构变化对土壤养分的影响

研究种植结构变化对土壤养分的影响,在理论上和实践上具有重要意义。以山东省寿光市4乡镇为例进行研究,结果表明：研究区在1980-2004年间种植结构发生了重大变化,这种变化引起土壤养分含量显著提高,土壤有机质平均提高26．33％,碱解氮平均提高28．77％,有效磷平均提高755．04％,有效钾平均提高194．35％;土壤微量元素中有效铁平均提高191．77％,有效锌平均提高487．77％,有效铜平均提高47．90％,有效锰平均提高22．83％,有效钼平均提高97．23％,有效硼平均提高76．80％;不同种植方式土壤养分提高的幅度不同,土壤有机质提高幅度的顺序为菜田〉粮田〉果园,碱解氮、有效磷、有效钾、有效锌和有效锰的顺序为菜田〉果园〉粮田,有效铁和有效铜顺序为果园〉粮田〉菜田,有效钼和有效硼顺序为粮田〉菜田〉果园;施肥量的提高是种植结构变化导致土壤养分根高的主要原因．

Effects of Planting Structure Changes on Soil Nutrients in Developed Coastal Region

The study of effects of planting structure changes on soil nutrients was important significance in both theory and practice.In the case of four towns of Shouguang in Shandong province,the research results indicated that,the planting structure have been considerably changed in this region from 1980 to 2004, and the soil nutrient contents significantly increased at the same times.The average value of soil organic matter content was increased by 26.3%.The contents of alkali-released nitrogen,available phosphorus and available potassium were increased by 28.77%,755.04% and 194.35%,respectively.The contents of available Fe,Zn,Cu,Mn,Mo and B in soils were also significantly increased by 191.77%,487.77%,47.90%,22.83%,97.23% and 76.80%,respectively.The ranges of soil nutrient increase were different in three different planting types.The order for the increase of soil organic matter was vegetable soil>grain crop soil>orchard soil.The order for the increase of alkali-release N,available P,K,Zn and Mn was vegetable soil > orchard soil > grain crop soil.The order for the increase of available Fe and Cu was orchard soil>grain crop soil > vegetable soil.The order for the increase of available Mo and B was grain crop soil >vegetable soil > orchard soil.The increase of amount of fertilizer application was the main reason for the result of soil nutrient increase from the planting structure changes.