色季拉山高山松林降雨再分配及重金属元素的时空特征研究

以色季拉山高山松林为研究对象，采用定位观测和室内分析相结合的方法，对雨季大气降雨、穿透雨和树干茎流中Fe、Mn、Zn、Cu、Cd元素进行了和测定分析，以期掌握高山松林大气降雨重金属元素循环特征。结果表明：高山松林对大气降雨的截留率19.70%～38.82%，穿透雨占大气降雨的71.48%，树干茎流占大气降雨的4.53%。各水相中pH值的大小顺序为大气降雨≈穿透雨>树干茎流，大气降雨、穿透雨、树干茎流量及各金属元素均表现为雨季盛期>雨季初期>雨季末期。雨季穿透雨中，Cd净淋溶为0，Fe、Zn净淋溶为负，分别为–0.005 mg/L和–0.008 mg/L。树干茎流中，Cd元素净淋溶为–0.001 mg/L。穿透雨与树干茎流中各重金属元素的净淋溶系数大小分别为Mn>Cu>Cd>Fe>Zn、Zn>Cu>Mn>Fe>Cd；穿透雨、树干茎流中各重金属元素的输入量均小于大气降雨，尤其是树干茎流，Cd、Fe、Zn元素的输入量为负。高山松林对重金属元素Cd、Fe、Zn具有吸收或吸附性，而对其他重金属元素具有淋溶效应。

Study on Temporal and Spatial Characteristics of Precipitation Redistribution and Heavy Metal Elements at Pinus densata Forest in Sejila Mountain

Taking Pinus densata forest in Sejila Mountain as the research object, and combining positioning observation and indoor analysis, the elements of Fe, Mn, Zn, Cu and Cd of precipitation, throughfall and stem-flow were analyzed in the rainy season, which grasped the cycle characteristics of heavy metal elements in precipitation in P. densata forests. The results showed that interception of precipitation by P. densata forest was 19.70% to 38.82%. The throughfall accounted for 71.48% of precipitation, whereas the stem-flow accounted for 4.53% of precipitation. The order of pH value each water phase was: precipitation ≈ throughfall > stem-flow. In the precipitation, throughfall and stem-flow and various metal elements all were the peak of the rainy season> the beginning of the rainy season> the end of the rainy season. In the throughfall of rainy season, the net leaching of Cd was 0, and the net leaching of Fe and Zn was negative, respectively –0.005 mg/L and –0.008 mg/L. In the stem-flow, the net leaching of Cd was negative, –0.001 mg/L. The net leaching coefficients of each heavy metal element in the throughfall and stem-flow were respectively Mn> Cu> Cd> Fe> Zn, Zn> Cu> Mn> Fe> Cd. The input amount of each heavy metal element in the throughfall and stem-flow was less than the precipitation, especially stem-flow. The input amounts of Cd, Fe, and Zn were negative. The P. densata forest has an ability to absorb Cd, Fe, and Zn, and an leaching effect on other heavy metal elements.