云南马龙县山地封育草地凋落物分解与氮释放的研究

以云南马龙县退化山地草地为研究对象,对封育2年草地的凋落物、土壤水分、凋落物含水率,以及氮素释放进行了研究.结果表明.围栏封育草地凋落物分解速率显著高于未封育草地凋落物分解速率(P<0.05),封育区凋落物增加.起到了一定的保温作用,即可以加速凋落物的分解.同时也减少冬季低温对山地草地的伤害;草地凋落物的干物质分解速率与土壤含水率、凋落物含水率呈显著正相关(r=0.949,P<0.05),封育增加了土壤的含水率,促进了凋落物的分解.总氮的含量与凋落物分解速率成正相关(r=0.995,P<0.05).氨素是调节草地凋落物分解速率的一个重要因素.

Effect of enclosure on litter decomposition and TN element release of grassland in Malong County of Yunnan province

The litter decomposition plays an important role in nutrient circle of grassland ecosystem.An experiment was conducted to determine the response of litter decomposition speed,soil water,water content of litter and TN release to enclosure of degradation grassland in Malong County of Yunnan province cross two year's enclosure.The results of this study showed that the speed of litter decomposition in enclosed grassland was significantly higher than in unenclosed grassland(P<0.05).The litter accumulation in the enclosed grassland could increase the temperature and enhanced the speed of litter,and reduced the harmfulness of low temperature to grassland.The speed of litter decomposition was positively correlated to soil water and water content of litter(r=0.995,P<0.05).The enclosure accelerated the speed of litter decomposition by increasing soil water.This study also indicated that the speed of litter decomposition was positively correlated to TN content of litter(r=0.995,P<0.05),and this implied that TN was an important factors to control the speed of litter decomposition in the grassland ecosystem.