干热河谷罗望子人工林凋落物分解及养分释放

通过长期野外监测和分析,研究了金沙江干热河谷罗望子人工林凋落物分解和养分释放动态,结果表明:经过420d分解期,林地A和林地B的凋落物残留率为42.57%和29.22%,半衰期为0.87a和0.75a,周转期为4.81a和3.61a;养分迁移方式,K元素是淋溶-富集-释放;N、Ca、Mg、Cu元素是富集-释放,Fe元素是富集,P元素在林地A和林地B中迁移方式略有差异;养分释放特征,P、Ca、Mg元素表现为净释放,七种元素释放率大小,林地A和林地B均为:Ca﹥K﹥P﹥Mg﹥N﹥Cu﹥Fe;P、K、Ca、Mg元素易分解和循环,返回林地时间较短,易被林木吸收。罗望子林凋落物的分解总体特征符合亚热带气候的地带性特点,受气温和降雨量影响较小。

Decomposition dynamics and nutrient release of litters of Tamarindus indica Linn.artificial forests in dry-hot valley,China

Based on field investigation and lab analysis,the decomposition dynamics and nutrient release of litters of Tamarindus indica Linn artificial forests were studied in Dry-Hot valley.The results showed that after 420 days of decomposition,the litters remaining rate in the two sites were estimated to be 42.57% and 29.22%,respectively.Derived from Olson equations,the 50% and 95% decomposition times for forest A and B were 0.87a and 0.75a,4.81a and 3.61a,respectively.The elements of K consistently showed the decomposition pattern of eluviation-enrichment-release.The elements of N,Ca,Mg and Cu consistently showed the decomposition pattern of enrichment-release.The element of Fe consistently showed the decomposition pattern of enrichment.The decomposition pattern of P was different in forest A and B.The elements of P,Ca and Mg consistently showed the nutrient release characteristics of simple release.The order of releasing speeds of elements from litter was Ca﹥K﹥P﹥Mg﹥N﹥Cu﹥Fe.The decomposition and cycle process of P,K,Ca and Mg were easy,and the four elements would be absorbed by trees easily.The decomposition characteristics of litters conformed the decomposition features of litters in subtropical climate.Temperature and rainfall couldn't effect on the decomposition of litters very good.