Evaluation On Water Conversation Function Of Forest In Mount Tai

Using principle of maximum capacity of forest inception storage, surrounding 5 indexes, function of water conservation of economic and protection forests in Mount Tai were studied in this thesis. The ecological and economical value were calculated and modified by the interrelated formula. According to multidimensional space theory and the law of coordinate evaluation, water conservation function of protection forests were analyzed, the sequence of good function was obtained. The main results are as follows:1. Precipitation interception function of three layers of different forest type: As the amount of rain turns from 5mm to 46mm, canopy interception storage and interception percentage turns from 1.53mm to 7.97mm and 30.65%~17.33% accordingly. The order of canopy interception storage from high to low is: pine forest, pine and oak mixed forest, arborvitae forest, oak forest, mono maple forest, pistache and locust mixed forest, locust forest, pistache forest.The litter holding storage increases with the thickness and amount of litter; the water absorb rate of litter is fast in early period, esp. before 0.25hr, can get 3.44～16.13mm/h, then turns slow, stops after 24hr. The order of litter holding storage from high to low is: pistache forest, pistache and locust mixed forest, locust forest, mono maple forest, oak forest, pine and oak mixed forest, arborvitae forest, pine forest.The maximum soil saturation water holding storage can get 1569.9t/hm2, the water holding capacity by unit area is 336.9t/hm2 more than CK. The order of non-capillary water holding capacity from high to low is: pistache and locust mixed forest, mono maple forest, pine and oak mixed forest, locust forest, arborvitae forest, pistache forest, oak forest, pine forest; and the order of infiltration rate from high to low is: locust forest,arborvitae forest, oak forest, pine forest, pistache and locust mixed forest, pine and oak mixed forest, pistache forest, mono maple forest.2. Effect on erosion reducing: the order of anti-erosion capacity of canopy from high to low is: pine forest, arborvitae forest, oak forest, pistache forest, mono maple forest, locust forest; and the order of soil erosion averting modulus from high to low is: oak forest, pistache and locust mixed forest, mono maple forest, pine and oak mixed forest, pistache forest, locust forest, arborvitae forest, pine forest, unit area.3. Comprehensive evaluation to water conservation function of protection forest: the order of water conservation function from high to low is: pine and oak mixed forest, pistache and locust mixed forest, mono maple forest, oak forest, locust forest, pistache forest, arborvitae forest, pine forest; and the pine and oak mixed forest has the best comprehensive function, which scored 0.3648, the pine forest has the worst comprehensive function, which scored 1.7409.4. Economic evaluation to water conservation of forest in Mount Tai: the substance mass amount of forest water conservation is 644.09 million ton, and the economic value of the current society level is 1.73 billion yuan; the water conservation increment amount is 207.49 million ton, and the economic value of the current society level is 555.83 million yuan; the quality of 212.84 million ton water is puried, and the economic value is 361.82 million yuan; the area of soil erosion reduction in every year is 219.23hm2, and the economic value of soil erosion averting by forest is 1.20 million yuan.