摘要
土地利用变化引起的水分条件变化反过来又会影响植被的生长,然而,森林-水分-植物生长之间相互作用关系的研究还很少。以香桂(Cinnamomum subavenium)人工林为例,在盐亭生态试验站开展观测,研究了无枯落物林地(FB)、有枯落物林地(FL)和裸地(BL)的水分动态(土壤水分、径流组成和径流量),比较了FB和FL样地树木高、基径、叶面积、比叶面积(SLA)、地上和地下生物量。研究结果表明:①FL样地的土壤含水量最高,其次是FB样地,而BL样地的土壤含水量最低;②地上径流展现了与土壤水分相反的趋势(FL<FB<BL),地下径流则表现出和土壤水分相同的规律(FL>FB>BL),3个样地的总径流量则没有表现出一个明确的大小关系。在观测期间,BL、FB和FL的地表径流量分别为284.68、222.93和68.98cm,地下径流分别为57.83、134.00和289.52 cm,总径流量依次为343.16、356.93和358.35 cm;③在观测早期,FL样地和FB样地植物形态学特征、SLA以及地上和地下生物量均没有显著差异(p>0.05)。在观测期末,虽然两个样地的基径和SLA无显著差异,然而其他指标差异极显著(p<0.005)。在观测末期,除SLA外,FL样地植物的高、基径、叶面积、地上生物量和地下生物量分别高于FB样地,表明该样地植物生长条件更好。这些结果表明森林改善了自身的水分环境,而水分环境的改善又反过来促进了森林的生长,森林植被-水分条件的这种相互促进作用是森林系统生存策略的一种表现。
Soil moisture and runoff changes resulted from land use change will, in turn, affect the plant growth and survival. However, research on the relationships between forest cover, water, and plant growth is rare. In this study, time series water dynamics （soil moisture, surface runoff, subsurface runoff and water yield） of forestland without surface litter （FB, litter removed）, forestland with ground litter plot （FL）, and bare land plot （BL, without vegetation cover） in Yanting Agro-ecosystem Station, SW China, were investigated. The height, basal diameter, leaf area, specific leaf area （SLA）, above- and below-ground biomass of plants in the FB and FL plot were compared. Results showed that： （~）FL plot revealed the highest soil water content （SWC）, followed by FB and BL; （2）the surface runoff for the three treatments trended to increase following an order of FL〈FB〈BL, whereas the subsurface flow showed a decreasing order of FL〉FB〉BL. The total runoff among the three plots didn＇t reveal a clear relationship. Throughout the study period, the surface runoff for BL, FB and FL was 284.68, 222.93 and 68.98 cm, the subsurface runoff was 57.83, 134.00 and 289.52 cm, and the total water yield was 343.16, 356.93 and 358.35 cm, respectively; and @at the beginning of the observation, the height, basal diameter, single leaf area, SLA, aboveground and belowground biomass for the FL plot trees were almost equal to those of the FB plot （p〉0.05）. At the end of the observation, the height, single leaf area, aboveground and belowground biomass between the two plots revealed significant difference （p〈0.005; FL〉FB）, but basal diameter and SLA didn＇t differ between FL and BL 07〉0.05）. The morphological characters （height, basal diameter and leaf area） and biomass of plants in FL plot were higher than those in FB plot, indicating that the former had better growth conditions than the latter. Forest improves its own water environment and water environment improvement, in turn, promote the growth of the forest. The mutual promotion effect between forest vegetation and its water condition is a kind of survival strategy of forest system.
出处
《生态环境学报》
CSCD
北大核心
2013年第8期1288-1296,共9页
Ecology and Environmental Sciences
基金
国家自然科学基金项目(31070405)
国家自然科学基金青年基金项目(41001018)
关键词
林地
水分动态
植物生长
生存策略
forestland
water dynamics
plant growth
survival strategy
