Grass Litter Decomposition Rate and Water-Holding Capacity in Dry-Hot Valley of Jinshajiang River

摘要

The decomposition rate and the water-holding capacity of 6 kinds of grass litters were studied in the Jinshajiang river dry-hot valley. The results showed that the dry weight remains reduced with time but did not have a direct correlation with time. The decomposi-tion litters were affected by climate, character of litter, animalcule and soil animal. The climate factors of temperature and humidity were important especially. The water-holding capacity was in the sequence of N. wightii (336%), P. notatum Flugge (248%), H. con-tortus (L.) Beauv (209%), B. pertusa (L.) A. Camus(206%), I. ende-caphylla Jacq (174%), D. annulatum (Forsk.) Stapf (168%). After 24 months decomposition the remaining dry weight of the litter was in the sequence as follows: 15.12% for N. wightii, 26.38% for I. ende-caphylla Jacq, 27.23% for B. pertusa (L.) A. Camus, 30.78% for P. notatum Flugge, 39.72% for H. contortus (L.) Beauv and 39.76% for D. annulatum (Forsk.) Stapf. The decomposition rate and wa-ter-holding capacity of N. wightii are at the highest level. It is impor-tant for the development, improvement and conservation of the grass-land soil.