| As important layers in function of forest water conservation, Forest land litter layer and soil layer played important roles in forest water conservation, soil and water conservation. The paper selected the middle-aged plantations of aerially-seeded Pinus massoniana plantations and its different proportions mixed forests with Schima superba in Xingguo county of Jiangxi province as study objects. The stands were divided four types according to the tree species mixed proportion, which were typeâ… (ten Pinus massoniana), type â…¡(eight Pinus massoniana and two Schima superba), type â…¢(seven Pinus massoniana and three Schima superba) and type â…£(six Pinus massoniana and four Schima superba). It discussed the litter standing crop and its water-holding characteristics, soil physical properties and its water-holding capacity by set up the typical sample plots and the methods of field investigation and indoor analysis. It would provide a reference for improving and enhancing the ecological function of aerially-seeded Pinus massoniana plantations, especially the function of water conservation. The main results were as follows:(1) The litter total standing crop of four types ranged from 1.16 t/hm2 to 4.58 t/hm2,the average of maximum water-holding rate ranged from 169.01% to 230.44%, the total of maximum water-holding capacity ranged from 1.97 t/hm2 to 10.56 t/hm2, the average of effective water-holding rate and the total of effective water-holding capacity ranged from 124.37% to 161.30% and 1.45 t/hm2 to 7.40 t/hm2 respectively, and all of them were type â…£>type â…¢>type â…¡>type â… . Except the average of effective water-holding rate of type â…£ and type â…¢ had no significant difference(P>0.05), the other indexes of different types had significant difference(P<0.05). The water-holding rate of litter undecomposed layer and half-decomposed layer had significant logarithmic relationships with immersion time, while the water absorption rate had significant power function relationships with immersion time(2) In the 0~80 cm soil layer of four types, the average soil bulk density ranged from 1.29 g/cm3 to 1.44 g/cm3, which were type â… > type â…¡> type â…¢> type â…£. The average of soil total porosity, capillary porosity and non-capillary porosity ranged from 36.00% to 46.24%, 30.95% to 36.80% and 5.05% to 36.80% respectively, and their orders were contrary to the average of soil bulk density. The maximum water-holding capacity, capillary water-holding capacity and non-capillary water-holding capacity of 0~80 cm soil layer ranged from 2 799.17 t/hm2 to 3530.96 t/hm2, 2 424.18 t/hm2 to 2 815.71 t/hm2 and 374.99 t/hm2 to 715.24 t/hm2 respectively, and all of them were type â…£> type â…¢> type â…¡> type â… . The soil bulk density, total porosity, capillary porosity, soil maximum water-holding capacity and capillary water-holding capacity of four types had no significant difference(P>0.05). Except that the non-capillary porosity and non-capillary water-holding capacity of 0~10 cm layer, 10~20 cm layer and 0~80 cm layer had no significant difference respectively(P>0.05), the others had significant difference(P<0.05).(3) Forest land(litter layer and soil layer) maximum water-holding capacity of four types ranged from 2 801.14 t/hm2 to 3 541.52 t/hm2, the effective water-holding capacity ranged from 76.44 t/hm2 to 722.64 t/hm2, and they were type â…£> type â…¢> type â…¡> type â… . The soil maximum water-holding capacity accounted for more than 99% of forest land maximum water-holding capacity, and its effective water-holding capacity accounted for more than 98% of forest land effective water-holding capacity. The value of forest land maximum water-holding capacity and its effective water-holding capacity ranged from 22 971.34 yuan/hm2 to 29 042.92 yuan/hm2 and 3 087.09 yuan/hm2 to 5 926.17 yuan/hm2 respectively. |
