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Ziwuling in the most vulnerable area of ??the ecological environment, whether in maintaining the the Loess Plateau ecological balance, regulating the regional climate, social and economic benefits still in play, have a very important role, and how to improve the ecological environment of the region has become the main task of the construction of the ecological environment in the area. Research in order to the Ziwuling main advantage forest tree species - the of Liaodong oak, pine, shekannesis study through field investigation and indoor analysis, clear the Liaodong oak, Chinese pine, the geographic distribution of shekannesis and basic biological characteristics; analysis their population dynamics, population regeneration of population characteristics; analysis of community structure, species composition and community characteristics, provide a theoretical reference for further research the Ziwuling District plant resource protection and its introduction and plantation. The main findings are as follows: an of Liaodong oak forest is mainly distributed in the distribution in Ziwuling 1200-1750 m above sea level at the district, in addition to the local forest is mingling with other trees, are generally pure forest understory shrub scattered distribution, the growth of low understory shrub cover 12% -25%, the average height of 0.6 m, 34.6% of the average coverage of the herb layer height between 12-24 cm; Chinese pine forest is mainly distributed in Ziwuling District 1350-1650 m above sea level at the shekannesis monospecific communities often form the population-based, shrub layer, the average coverage of 11% -29%, the average height of 1.3 m, 42.6% of the average coverage of the herb layer, between 9-26 cm in height; Ziwuling area 1200-1450 m above sea level at the multi-growth, multi-distribution Chunlin mainly shrub layer cover between 36% -60%, with an average plant height of 0.5-1.6 m, the herb layer cover 10% - 26%, the average height of 10-28 cm. Ziwuling area oil pine forests are relatively the same age forest, the Liaodong oak forest belongs to the relatively uneven-aged forest, Chai Sung-lin are uneven-aged forest, three populations of the number of individual survival decreased with increasing age, but its intensity or rate of death not consistent with the strength of Liaodong oak early death than Chinese pine and shekannesis to high; the P. tabulaeformis shekannesis population structure for growth. Fitting equation of the relationship of the Liaodong oak, pine, firewood pine height and diameter, respectively: y =-0.0081x2 0.6996x 0.023, y =-0.0177x2 0.8551x - 0.0874 and y =-0.0056x2 0.8286x - 0.274, Liaodong The average diameter oak stand Dg 21.06 cm, the average height of 11.16 m; Chinese pine forest in average diameter Dg11.49 cm, the average high 7.40 m; shekannesis Dg 17.16 cm, the average height of 12.30 m. 3 5 m × 5 m, 5 m × 10 m and 10 m × 10 m sampling area, oak, pine, shekannesis population spatial pattern showed an aggregated distribution, and with the increase of the sampling area three populations gathered degrees were shown a small → large → small trend; populations with increasing stand age distribution tends to be randomly distributed by the congregation. Ziwuling forest area Liaodong oak forest, pine forest, Chai Sung-three forest types, the oil pine species richness index (Margalef index) and plant evenness index (Pielou index) is the largest, and Chai Sung-lin The diversity of the tree layer is poor, the species is not abundant. Three Forests tree layer, shrub layer, herb layer three diversity indices showing characteristics from low to high. Forest structure and understory physical environment, the gaps the understory seedlings updates by human disturbance factors and their interactions are different, the survey results show: the Liaodong oak forest seedling regeneration 80-210 plants / hm2 ; the Pinus tabulaeformis pure forest of 27-60 plants / hm2 mixed forests 55-190 plants / hm2; Chai Sung-lin seedlings generally 150-220 plants / hm2 the Ziwuling Liaodong oak forest litterfall volume 32.65 t/hm2, the water content of the litter was 105.5%, the the maximum interception amount 50.93 t/hm2, effective interception amount to 38.13 t/hm2; the the oil pine litterfall volume to 48.95 t/hm2, litter moisture 125.9%, the maximum interception amount to 70.15 t/hm2, the effective interception amount to 50.38 t/hm2; Chai Sung-lin Litters volume to 47.30 t/hm2, the water content of the litter was 121.5 percent, the biggest interception amount to 61.68 t / hm2, the effective interception amount to 43.81 t/hm2.
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