【摘要】 通过样方调查和采样,对元谋干热区2年生不同种植密度木豆人工林养分的营养循环和养分利用效率进行了研究。结果表明,不同种植密度下林分的营养循环表现出了一定的差异性,而养分的利用效率则一样。0.8×0.8m2、1.0×0.8m2和1.0×1.0m2种植密度下林分的养分吸收量分别为1497.64、1326.26和1046.00kg/(hm.2a),其中从土壤中年吸收养分量以Ca最多,N、K次之,Mg、P再次,Fe、Cu最少,且随种植密度的增大呈增加趋势;养分的归还量分别为476.30、729.95和518.98kg/(hm.2a);存留量分别为753.34、596.3和527.07kg/(hm.2a);大量元素养分的循环速率分别为0.49、0.55和0.49,微量元素养分循环速率分别为0.79、0.83和0.80。据此提出,对于生长旺盛后期的林分,采取适量施肥和调整林分密度等经营措施,提高养分的利用效率,增加林分对养分的吸收量和存留量。同时得出1.0×0.8m2的种植密度更有利于系统内营养元素的生物循环、养分利用效率和保持地力持久。与油松、刺槐、板栗、锥栗等相比,木豆对养分的利用效率明显偏低。更多还原

【Abstract】 Cajanus cajan is one of the most important plants that plays an irreplaceable role in ecological environment protection. In order to provide scientific utilization and management about it, we took the sample plot in Yuanmou dry-hot Region and studied the nutrient cycling and the efficiency of nutrient utilization of the C cajan 2-year old plantation in the different planting densities. The results showed: the nutrient cycling was different among the different planting density of C. cajan, but the efficiency of nutrient utilization was same among the different planting densities .The quantity of annual nutrient absorption of 0.8×0.8m2,1.0×0.8m2 and 1.0×1.0m2 planting density was 1499.64,1326.26 and 1046.01kg/(hm2·a) respectively, and the annual adsorption amount of each element from soil was different , Ca is most , then followed by N and K, Mg, P, Fe and Cu . The absorption of these elements trended to increase with the higher planting densities, the return was 476.30,729.95 and 518.98 kg/(hm2·a) respectively. The retention was 753.34,596.3 and 527.07 kg/(hm2·a) respectively; the cycling ration of macronutrient was 0.49、0.55 and 0.49 and the cycling rate of micronutrient was 0.79,0.83 and 0.80 respectively. The results also showed that the planting density of 1.0×0.8m2 was more effective in using the nutrient cycling and the nutrient efficiency utilization and keeping soil of sustainable development. Compared with those of Pine,Black locust Castanca mollissima Blume and Castanopsis, the nutrient utilization efficiency of C. cajan was evidently lower , particularly for N and Ca.更多还原