| This paper takes masson pine natural secondary forests(age 45-70)in Chongqing TieShanPing as the research object, the hydrology functions of pinus massoniana forest canopy and soil layer are analyzed, and combination of masson pine tree trunk flow and litter change to understand the water and material circulation situation of the stands, assess the health status of masson pine forest in TieShanPing, so as to provide the basis for forest management. in. TieShanPing.(1) Pinus massoniana forest area accounted for absolute quantity in TieShanPing, Chongqing, the forest canopy density is generally above 0.7. Broadleaf tree species such as camphor, schima superba, has only a small distribution, and mostly at the level of pressed wood, and few pure broadleaf forest distributed.(2) The most components of the forest litter in coniferous forests and coniferous and broadleaved mixed forest mainly are leaves, more worm dung is characterized in coniferous forest litter, and the phenomenon did not appear in mixed needle leaf illustrate that the mixed forest can reduce the Masson Pine by pine caterpillar damage. The peak of the litter amount in the month of February to April and August, peak litter content accounts for about 63% of the total litter, at this time for TieShanPing forest region in water less, forest litter is concentrated in the summer drought period. The coniferous forest in TieShanPing is more sensitive to the change of the forest water, coniferous forest health is in a worrying situation, broad-leaved forest and coniferous and broad-leaved mixed forest can better adapt to the TieShanPing forest environment.(3) The soil water content under masson pine forest in Chongqing TieShanPing has a significant space-time characteristic of "peak- valley" type change, the lowest value is on August and September, totally the soil moisture content with the increase of soil depth, water content decreased first and then increased, and the soil water content differ greatly among different soil layers. Soil moisture is mainly affected by slope position, the water condition of uphill is better than that of downhill, slope direction has little effect. Shallow soil moisture is mainly affected by solar radiation? temperature and precipitation, and that in 40-60 cm get more influence from plant roots.(4) During the observation period, 37 field rainfall process was observed, total rainfall 998 mm penetrating rainfall 872.19 mm, average penetration ratio in 87.39% and rainfall penetration ratio is much higher than the 76% of the healthy masson pine; stemflow 6.27 mm., accounting for 0.54% of the rainfall outside the forest, the stemflow generated rainfall threshold was 3.9mm, lower than that of the healthy forest 6-8mm; the canopy interception was 119.54 mm, accounted for only 11.98% of the rainfall outside the forest, in the forest canopy interception ratio of the lowest level in China(11.4%-36.5%).The evapotranspiration of Masson pine forest was 417.33 mm, accounted for 57.48% of the rainfall, runoff is 212.29 mm, accounting for 29.24% of the rainfall outside the forest. Transpiration ratio is lower than that of healthy pine forest evapotranspiration, runoff is higher than that of healthy Masson runoff, the masson pine in TieShanPing canopy sparse problems exist, the rainfall interception and transpiration decreased significantly. |
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