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以三峡库区汝溪河流域165~170m和170~175m两个海拔段的人工种植柳树土壤为研究对象,比较两个海拔段土壤的化学性质在一个淹水周期前后的变化特征,包括土壤pH值、有机质(OM)、碳氮比(C/N)、全氮(TN)、硝态氮(NO-3-N)、铵态氮(NH+4-N)、全磷(TP)和有效磷(AP)含量,并设置裸地土壤作为空白对照.结果显示,三峡水库消落区不同海拔高程的柳树生长状况良好,水淹后生长于高海拔的柳树较低海拔的柳树冠幅和胸径分别高出22.2%和48.8%;对于裸地土壤,经过淹水后其pH值趋向中性变化,全氮和铵态氮含量增加,硝态氮含量下降;与裸地相比,栽植柳树的土壤全磷含量显著升高,碳氮比、有效磷、有机质、铵态氮含量显著下降.研究表明,柳树良好的适应能力使其能在三峡库区消落带大量存活,但是由于其土壤N,P营养元素含量的增加而对水体富营养化问题的产生存在一定的贡献潜力也是不容忽视的.
The willow soils from 165 to 170m and 170 to 175m in the Three Gorges reservoir area were selected to study the changes of soil chemical properties at two altitudes before and after a flooding cycle including soil pH (OM), C / N, TN, NO-3-N, NH + 4-N, total phosphorus The content of available phosphorus (AP) and bare soil as a blank control.The results showed that the canyon at different elevations in the Three Gorges Reservoir area had a good growth condition and the willow crown at the lower elevation of the willow trees growing at high altitude after flooding, The breast diameter was 22.2% and 48.8% higher than that of the bare land respectively. After immersed soil, the pH values tended to be neutral, the content of total nitrogen and ammonium nitrogen increased, and the content of nitrate nitrogen decreased. Compared with bare land, The content of C and N, available phosphorus, organic matter and ammonium nitrogen decreased significantly.The results showed that the good adaptability of willow tree could make it be able to survive a lot in the hydro-fluctuation belt of the Three Gorges reservoir area, but due to its soil N, P nutrient content of the increase of water eutrophication problems there is a certain contribution to the potential It is overlooked.