| As a key forest district in Fujian Province, the Northern Fujian, was a major region of Phyllostachys. edulis's distribution and cultivationm, with a total area of 361 thousand hectares accounting for 40 percent of Fujian province and 10 percent of China at present. The bamboo industry has witnessed rapid development, local farmer earned 984 Yuan every year from bamboo industry which took 25 percent of their total yearly income. The local people pursuit of ecomomic extensively, as a result, the pure P. edulis forest took a dominate position, furether more, the forest stucture had been broken, bamboo wood production had been decreased. To make the matters worse, the ecological problems such as soil erosion, soil productivity maintenance were seriously. The characteristics of hydrological of three typical P. edulis forests (P. edulis and Cunninghamia lanceolata mixed forest-â…¡, P. edulis pure forest -â…¢and P. edulis and broad-leaved tree mixed forest -â…£) in the North of Fujian province were studied in comparison with C. lanceolata forest-â… and evergreen broadleaved forest-â…¤.Based on the position research, three major research spaces like atmosphere, plant and soil subsystems were studied. Through researching rainfall characteristics, canopy interception characteristics, water retention characteristics of litter, soil infiltration characteristics, soil water content characteristics, runoff of surface soil to disclose the relationship between forest and hydrological functions and eco-hydrological functions of different P. edulis forests in North of Fujian.Based on analysis of eco-hydrological of different types forest, the method of analytic hierarchy process (AHP) was applied to establish the eco-hydrological hierarchy function and ecological functions were employed to give evaluation. To provide theoretical and technical guidances for P. edulis forest sustainable management in Northern Fujian, and also accumulate field experience for researching ecological functions of bamboo forestry. The main conclusions were as follows:(1) Through 3 years orientation research, the results showed that: The canopy interception capacity of broad-leaved tree forest was best. The canopy interception ratio ranged from 14.13% to 53.49%, that the order was:â…¤(31.33%)>â…¡(28.17%)>â…£(23.48%)>â…¢(22.88%)>â… (22.29%). The throughfall rates ranged from 46.23% to 86.22% , stemflow rates ranged 0.73% to 2.87%. Throughfall, stemflow and canopy interception were linearly correlated to rainfall outside the stands at the extremely significant level (p<0. 01), that the equation y = a + bX could used to show the relationship between the rainfall and througfall, and three curve equation (y =β0 +β1X +β2X2 +β3X3) was used to explain the relationship between rainfall and canopy interception The pure P. edulis forest had a higher intercept ability with even distribution canopy to the small rainfall interception, as rainfall depth increased, canopy interception of all the stands increased, and the rates of canopy interception decreased. By used canopy store water capacity and the leaf area index, built a conceptual model of canopy interception, what's more, the data from model and experiment have a high fitting degree.(2) The order of litter return amount of different forest types was:â…¤(3.28 t·hm-2·a-1)>â… (1.73 t·hm-2·a-1)>â…¢(1.63 t·hm-2·a-1)>â…£(1.62 t·hm-2·a-1)>â…¡(1.06 t·hm-2·a-1). The experiment of litter interception in representative rain showed that the litter interception rate of pure P. edulis forest was the lowest while P. edulis and C. lanceolata mixed forest was highest when the rainfall amount was small, rainfall intensity was slightly and lasted short. The order of litter interception was:â…¡(57.63%)>â… (53.09%)>â…£(30.59%)>â…¤(29.40%)>â…¢(28.48%). When the rainfall amount was large, rainfall intensity was strongly and lasted long time, the litter interception rate of pure P. edulis forest was still lowest, but the litter of C. lanceolata forest had highest intercepting capability. The order of litter interception was:â… (24.33%)>â…¤(21.59%)>â…¡(20.53%)>â…£(15.98%)>â…¢(13.56%). Generally speaking, the five different forests had higher intercepting capability with slighter rainfall, on the contrary, lower intercepting capability with stronger rainfall.(3) The seasonal variation of soil water content was basically the same with the rain seasonal variation in region, the monthly average soil water content of five different stands ranged from 22.98% to 37.88%. The result showed that the water conservation function all the forest types was well for the high and even distribution annual soil water content. In all, the soil water content of forestry were highest in evergreen broadleaved forest, the second in P. edulis and C. lanceolata mixed forest and broad-leaved tree mixed forest, the lest in pure P. edulis forest. Principal component analysis showed that illumination intensity, air temperature inforest, surface temperature and 0-60 cm soil layer temperature deicided microclimate characteristic under forest. Obtained a non-linear model about the root system density and the soil moisture content by non-linear nelson-siegel, the model indicated that root system density close related to the soil moisture distribution The path analysis showed that the soil physical character immediate influence to the soil water-holding and retaining capacity directly, meanwhile the max water-holding capacities was the maximum effective factor.(4) Rainfall and surface runoff were measured on the plots through in situ method of catchment. Results showed that the production of surface runoff was mainly related with the amount of precipitation, heavy and torrential rain were major source of the runoff, only when rains ammount more than 5 mm, the five forestlands produced surface runoff. The marginal value of each foreststands produced surface runoff was different,C. lanceolata forest was 6.11 mm, P. edulis and C. lanceolata mixed forest was 6.21 mm, pure P. edulis forest was 5.15 mm, P. edulis and broad-leaved tree mixed forest was 5.9 mm, evergreen broadleaved forest was 6.21 mm.The annual runoff of forestry were highest in pure P. edulis forest, the lest in evergreen broadleaved forest, the order of it in different stands was:â…¢(28.1 mm)>â…£(16.2 mm)>â… (14.4 mm)>â…¡(13.2 mm)>â…¤(12.6 mm). Grey correlation analysis on factors influencing hydrological effects was conducted, and the importance sequence of factors was the content and storage of ground coverage> litter available water capacity > species richness> stand height> content and storage of litter> final soil infiltration rate> shrubs coverage> tree crown density > soil available water capacity= soil porosity. The evergreen broadleaved forest had a highest rational degree of precipitation with surface runoff, and the P. edulis and C. lanceolata mixed forest had a lest one. The rational degrees of different vegetation types descend in the order ofâ…¤(0.763)>â… (0.756)>â…£(0.697)>â…¢(0.621)>â…¡(0.529).By used the method of water-balance, the results showed that forest evaportranspiration was the most part of woods water output which make up 97.69 to 99.12 percent of the total water input. The actual expenditure of all foreststands was less than the actual input water, therefore, the rainfall could guarantee that plant normal water metabolism, without additional requirement from the soil moisture system in experimental plots.(5) The method of analytic hierarchy process was applied to establish the eco-hydrological hierarchy function model under 13 indicators of ecological functions, and integrative grades were employed to give evaluation. The results showed that the score of eco-hydrological function of the five forestlands ranged from 0.627 to 0.877, the final integrative evaluation order was:â…¤(0.877)>â… (0.805)>â…£(0.783)>â…¡(0.684)>â…¢(0.627). The hydrological and ecological functions of stands were evaluated by using the methods of shadow price method, that the order was:â…¤(1 546.46 yuan·hm-2)>â…£(1 467.54 yuan·hm-2)>â…¡(1 357.23 yuan·hm-2)>â… (1 322.91 yuan·hm-2)>â…¢(1 273.87 yuan·hm-2).To sum up, comprehensive evaluation on the three different types of maso baboo forests'eco-hydrological function showed that the eco-hydrological function of P. edulis and broad-leaved tree mixed forest was highest. The pure P. edulis forest which aim to economic produce had lowest eco-hydrological function not only in canopy layer but also in litter and soil layer. So the mixed P. edulis forest could play a better role in improving water and soil conservation in hills and mountains of Northen Fujian. There was large areas of hills and mountains in Northern Fujian, that the landslide and soil erosion easily to happen.Thought about that the mixed moso bamboo forest could improve the eco-hydrological function, exspecially P. edulis and broad-leaved tree mixed forest. Mixed P. edulis forest would be conducive to sustainable development with high economic, and ecological benefits.
|
PDF Full Text Request