福建滨海木麻黄林下土壤性质的变化及其对林带更新的影响

研究了福建滨海沙地木麻黄防护林Ｍｏ的生物地球化学循环特征和林下土壤ｐＨ的变化，发现因Ｍｏ的生物地球化学循环不平衡引起的土壤微量元素Ｍｏ的耗竭和土壤的酸化是木麻黄林早衰和迹地更新生长不良的重要原因。提出了相应的对策建议。

THE CHANGE IN SOIL PROPERTIES UNDER BEEFWOOD SHELTER BELT ON THE AEOLIAN SANDY COAST IN FUJIAN AND ITS INFLUENCE ON THE REFORESTATION OF THE SLASHLAND

Beefwood (Casuarina equisetifolia) is the tree of the first importance for windbreak. sand fixation and ecological improvement on the aeolian sandy coast of Fujian. But the reforested beefwood on the slashland do not grow well and are not healthy.The study on the causes of this problem and on the countermeasures are urgently needed for safeguarding the ecological environment. The authors studied the biogeochemical characters of N, P, K, Na. Ca, Mg, Cu, Zn. Fe, Mn, B. Mo. in the beefwood shelter belt on the coast land on the Haitan Island. Fujian. It was found that the trace element Mo in the soils under beefwood forest will be exhausted with the growing of the trees becouse of the unbalanced cycle of the element. Moreover the PH values of the soils will decline, which will further reduce the availability of Mo in the soils. The Mo-exhaustion and acidization of the soils result in a decrease in the content of Mo in beefwood and leads to the unsatisfactory growth of the succeeded beefwood on the beefwood-slashland on sandy coast land in Fujian. According to above results.the authors put forward some countermeasures to preserve and promote the beefwood shelter belt and the ecological environment on the coast in Fujian.