Analysis of Water-holding Capacity of Litters in Three Types of Near-mature Plantations in the Jinsha River Valleys

To understand the litter water-holding capacity of near-mature plantations in the jinsha river basin,studies were made of litter reserves, water-holding capacity, water-holding rate and water absorption rate in three typical forest types of the jinsha river basin.The results showed that dry litter reserves, water holding capacity, water holding rate, water absorption rate were different in different types of forest, the order of the indexes above were all as follows:softwood forest litter (Alnus cremastogyne) > hardwood forest litter (Cyclobalanopsis glauca) > coniferous forest litter (Pinus armandii). the variation rule of water holding capacity, water retention rate and the immersion time conformed to the logarithmic equation W=a×ln(T)+b (where a and B were constants), water absorption rate and time variation rule conformed to power equation W=a×t^-b, and the difference reached the significant level (P<0.05). Softwood forest had higher water retention than the other two forest types. Through monitoring and research of dynamic variation on litter water holding capacity in three kinds of plantations, natural water content of litter varied between 13.75% and 63.62%, water-holding rate of undecomposed litter and half-decomposed litter varied respectively in 85.05%~323.41% and 147.66%~251.11%, the later varied in a smaller amplitude.