信丰森林健康示范区主要森林枯落物持水与蒸发特征研究

Hydrological Function of Litter Layers under Different Forests at the Demonstration Area of Forest Health Management Project in Xinfeng County,Jiangxi Province

采用野外取样与室内实验相结合的方法,对江西省信丰县森林健康项目示范区常绿阔叶林、杉木(Cun-ninghamia lanceolata)林、湿地松(Pinus.elliotii)林、马尾松(P.massoniana)林、毛竹(Phyllostachys pubescens)林、火炬松(P.taeda)林、灌木林7种主要森林类型枯落物储量、持水量、持水率与蒸发速率等指标进行研究。结果表明:(1)杉木林凋落物储量最大,为9.79 t/hm2;其次是常绿阔叶林(8.72 t/hm2)、火炬松林(8.24 t/hm2)、湿地松林(7.77 t/hm2)、灌木林(7.54 t/hm2)、毛竹林(4.66 t/hm2);马尾松林最小,只有3.80 t/hm2。最大持水量依次是杉木林(18.31 t/hm2)、灌木林(15.23 t/hm2)、常绿阔叶林(15.01 t/hm2)、火炬松林(12.50 t/hm2)、湿地松(10.24 t/hm2)、毛竹林(9.02 t/hm2)、马尾松林(6.54 t/hm2),其最大持水率分别是187.06%、201.92%、172.22%、151.66%、131.68%、193.41%和172.15%;凋落物蒸发速率呈现湿地松林>毛竹林>火炬松林>马尾松林>灌木林>杉木林>常绿阔叶林的特点;(2)凋落物持水率随浸水时间增加而增加,随蒸发时间增加而减少,二者分别可用方程Rs=t/(a+bt)与Re=a-t/(b+ct)进行较好的拟合;(3)从各项水文特征指标来比较,阔叶林、杉木林水文生态效应最好,马尾松林、湿地松林最差。

Investigations were carried out on the storage, water holding capacity and evaporation rate of seven types of forest litters in Demonstration Area of Forest Health Management Project in Xinfeng County, Jiangxi Province. Laboratory tests resulted that： （ 1 ） The litter storage （ t/hm^2 ） of Cunninghamia lanceolata plantation was the largest （9. 789） among the 7 forests,followed by the evergreen broad -leaved forest （8.715）, Pinus taeda plantation （8. 241 ） ,P. elliotii plantation （7. 774 ）, Shrubbery （7. 541 ）, Phyllostachys pubescens plantation （4. 663 ） and P. massoniana （3. 801 ）. The order of maximum water holding capacity was：C. lanceolata plantation 〉 shrubbery 〉 evergreen broadleaved forest 〉 P. taeda plantation 〉 P. elliotii plantation 〉 Phyllostachys pubescens plantation 〉 P. massoniana forest, their proportional water holding capacity as a percentage of the litter nature dry weight were 187.06,201.92,172.22,151.66,131.68,193.41 and 172.15 respeetively, and the order of the evaporation rate of absorbed water in litter was P. elliotii plantation 〉 Phyllostachys pubescens plantation 〉 P. taeda plantation 〉 P. massoniana forest 〉 shrubbery 〉 C. lanceolata plantation 〉 evergreen broadleaved forest; the water holding capacity of litter in all forests increased with the increase of water immersion time and decreased with evaporation time. The relationship between water holding capacity and immersion time was R, = t/（a ＋ bt） ;the relationship between water holding capacity and evaporation time was R, = a -t/（b ＋ ct）. Comparative analysis showed that the evergreen broadleaved forest and C. lanceolata plantation had the best hydrological effects,the last was P. massoniana forest and P. eliiotii plantation.