Water Conservation Function Of Picea Schrenkiana Forest Ecosystem In Mount Tumor Nature Reserve

Mount Tumor Nature Reserve is a very important water supply area in Xinjiang,and its water conservation function of forest ecosystem is of great significance in alleviating regional water shortage and adjusting regional water balance.To evaluate the water conservation capacity of forest in Mount Tumor Nature Reserve quantitatively,comprehensive water storage capacity method were used to investi-gate the canopy interception capacity?C?,litter water-holding capacity?L?,soil water storage capacity?S?of Picea schrenkiana forest ecosystem in the upper Tailan River,then made a comprehensive evaluation of its Water Conservation Function.The result shows that:?1?In the four sample areas,while the canopy interception capacity is the Middle elevation Spruce forest?29.94 mm?>High elevation Spruce forest?20.56mm?>Higher altitude Spruce forest?11.72 mm?>Low altitude Mixed Broad leaf-conifer Forest?5.84 mm?,and the stem flow is the opposite.?2?Except for Middle elevation Spruce forest,the average thickness of undecomposed litter is thicker than the intermediate decomposed layer;while the largest average volume of decomposed layer is Higher altitude Spruce forest(79.32t·hm^-2),while the largest intermediate decomposed layer is Middle elevation Spruce forest(59.47 t·hm^-2).On the whole,the rank of the maximum water holding capacity is Middle elevation Spruce forest?32.55 mm?>Higher altitude Spruce forest?31.05mm?>High elevation Spruce forest?30.78 mm?>Low altitude Mixed Broad leaf-conifer Forest?12.84 mm?.?3?The dynamic variation rule of water-holding capacity and water-absorption rate of humus with increasing soaking time were basically the same among the litter layer in p.schrenkiana forest at different altitudes.The water amount soaked of both the under-decomposed and semi-decomposed litters were rapid within 2 h,reached its maximum at the soaking time of 12 h.Water holding capacity at different levels of litter in the Middle elevation Spruce forest were higher than that other sample plots at the same time.The water absorption rates of litters were higher within 0.5 h,the water holding is near saturation up to 12 h.Within the initial 2 h,The 4 kind of forest litter layer in the same immersion time in semi-decomposed layer water absorption rate were higher than the under-decomposed layer.The variation of water-holding amount and water absorption rate of both the under-decomposed and semi-decomposed humus layers with the soaking time followed a significant logarithmic function and a significant power function,respectively.?4?The average change range of sample 4's soil bulk density is from 0.73g·cm^-33 to 1.06 g·cm^-3;The average soil porosity and water holding capacity of capillary pore in 30 cm deep soil layer,both were Middle elevation Spruce forest>High elevation Spruce forest>Higher altitude Spruce forest>Low altitude Mixed Broad leaf-conifer Forest;Overall,the soil moisture content of natural forest is increasing with the increase of the altitude;The average water holding capacity of non-capillary pore in 30 cm deep soil layer were Middle elevation Spruce forest?37.6 mm?>High elevation Spruce forest?30.7 mm?>Higher altitude Spruce forest?25.73 mm?>Low altitude Mixed Broad leaf-conifer Forest?13.92 mm?.?5?The soil initial infiltration rate and soil steady infiltration rate of the 4 shrub types with different soil depths are obviously different,In the initial infiltration rate,infiltration rate and infiltration capacity,The higher altitude Spruce forest were best,Then the Low altitude Mixed Broad leaf-conifer Forest were the worst;infiltration rate and infiltration time was power function,The correlation coefficients R of the fitted power function curves are above 0.95.The results showed that the ability of water conservation of The higher altitude Spruce forest was the best.?6?The comprehensive water conservation capacity of the forest ecosystems in the study area is from 141.12 mm to 280.84 mm,Low altitude Mixed Broad leaf-conifer Forest has the smallest water holding capacity,while Middle elevation Spruce forest is the largest.The soil layer contributed the most to water conservation,made a proportion between 77.75%to 86.96%;Comprehensive effective water storage capacity is far less than the theoretical total capacity,but can work well in the water conservation function as well as water and soil conservation effect.