Structural properties of forest soils have important hydro-ecological function and can influence the soil water-physical characters and soil erosion. The experimental soil samples were obtained in surface horizon (0-1...Structural properties of forest soils have important hydro-ecological function and can influence the soil water-physical characters and soil erosion. The experimental soil samples were obtained in surface horizon (0-10 cm) from different subalpine forest types on east slope of Gongga Mountain in the upriver area of Yangtze River China in May 2002. The soil bulk density, porosity, stable infiltration rate, aggregate distribution and particle-size distribution were analyzed by the routine methods in room, and the features and effects on eco-environment of soil aggregation were studied. The results showed that the structure of soil under mixed mature forest is in the best condition and can clearly enhance the eco-environmental function of soil, and the soil structure under the clear-cutting forest is the worst, the others are ranked between them. The study results can offer a basic guidance for the eco-environmental construction in the upper reaches of Yangtze River.展开更多
Because of the distinction of soil property and humus content, soil water content is not ideal to indicate whether it is suitable to the growth of plant. Mainly based on the PF-a numerical value denoting the water reg...Because of the distinction of soil property and humus content, soil water content is not ideal to indicate whether it is suitable to the growth of plant. Mainly based on the PF-a numerical value denoting the water regime of soil and connected with the growth of plant, the study combined the moisture percentage of soil with PF to research in quantity the interrelation between the moisture percentage and PF in different succession phases of subalpine dark coniferous forest in Gongga Mountain. The results showed that: (1) In the same PF value, the moisture percentage in humus horizon increased gradually with the devel-opment of the succession of the dark coniferous forest; The moisture percentage of over-mature forest was the highest and>mature forest>half-mature forest>young growth forest; (2) With the increase of soil depth, the soil bulk density increased and the moisture percentage decreased, but the difference in the percentage of moisture was not notable in different succession phases. (3) In different succession series, the vegetation affected the soil water characteristics by increasing the soil organic matter, improving the soil construction, receding the soil bulk density and enhancing the soil porosity; (4) The humus horizon of the dark coniferous forest soil has the highest water holding capability in this region.展开更多
Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters） （SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson） （FF）, and birch （Betula platyphylla Sukaczev） （BF） ...Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters） （SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson） （FF）, and birch （Betula platyphylla Sukaczev） （BF） subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter （LL） than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems.展开更多
Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF),...Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF), in WesternSichuan, China, in order to understand the key factors that influenced litter production and dynamics. Litterfall in thethree forests consisted mainly of leaves, woody litter, reproductive organs and moss. Contribution of leaf litter to thetotal litterfall was significantly (P < 0.05) greater than that of woody litter, reproductive organs or moss. Regardlessof the stands, litterfall exhibited a marked monthly variation with the maximum litterfall peaks occurring in October,with smaller peaks occurring in February for SF and FF, and May for BF. The analysis indicated that tree species,stand density, leaf area index (LAI), stand basal area and stand age were the key factors determining litter production.Meanwhile tree species and phenology controlled the litter dynamics, with wind and snow modifying the litter componentsand dynamics.展开更多
The “blind-ear” as a Cu deficiency symptom in wheat on upland soils in the hilly area of Zhejiang Province was discussed in this paper.Through 3 years of field experiments,it was elucidated that “blind-ear” in whe...The “blind-ear” as a Cu deficiency symptom in wheat on upland soils in the hilly area of Zhejiang Province was discussed in this paper.Through 3 years of field experiments,it was elucidated that “blind-ear” in wheat plant appeared due to the low level of available Cu in the soils,and the critical value 3 mg/kg for total Cu in the plant at grain filling stage and 1 mg/kg for available Cu(0.1 M HCl)in the soils.A basal dressing of 30 kg/ha of Cu sulfate to the soils could completely eliminate Cu deficiency symptoms,obtain normal grain yield and have residual effect for at least 3 years.展开更多
基金This study was supported by the Knowledge innovation project of Chinese Academy of Sciences (KZCX2-Sw-319)
文摘Structural properties of forest soils have important hydro-ecological function and can influence the soil water-physical characters and soil erosion. The experimental soil samples were obtained in surface horizon (0-10 cm) from different subalpine forest types on east slope of Gongga Mountain in the upriver area of Yangtze River China in May 2002. The soil bulk density, porosity, stable infiltration rate, aggregate distribution and particle-size distribution were analyzed by the routine methods in room, and the features and effects on eco-environment of soil aggregation were studied. The results showed that the structure of soil under mixed mature forest is in the best condition and can clearly enhance the eco-environmental function of soil, and the soil structure under the clear-cutting forest is the worst, the others are ranked between them. The study results can offer a basic guidance for the eco-environmental construction in the upper reaches of Yangtze River.
基金The Development Plan of the State Key Fundamental Research of China (973), contract No. 2000046807 and by Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX2-405)
文摘Because of the distinction of soil property and humus content, soil water content is not ideal to indicate whether it is suitable to the growth of plant. Mainly based on the PF-a numerical value denoting the water regime of soil and connected with the growth of plant, the study combined the moisture percentage of soil with PF to research in quantity the interrelation between the moisture percentage and PF in different succession phases of subalpine dark coniferous forest in Gongga Mountain. The results showed that: (1) In the same PF value, the moisture percentage in humus horizon increased gradually with the devel-opment of the succession of the dark coniferous forest; The moisture percentage of over-mature forest was the highest and>mature forest>half-mature forest>young growth forest; (2) With the increase of soil depth, the soil bulk density increased and the moisture percentage decreased, but the difference in the percentage of moisture was not notable in different succession phases. (3) In different succession series, the vegetation affected the soil water characteristics by increasing the soil organic matter, improving the soil construction, receding the soil bulk density and enhancing the soil porosity; (4) The humus horizon of the dark coniferous forest soil has the highest water holding capability in this region.
基金Project supported by the National Natural Science Foundation of China (Nos. 30471378, 90202010 and 30211130504)the Applied and Basic Research Program of Sichuan Province, and the Talent-Recruiting Program of Sichuan Agricultural University
文摘Macronutrients （N, P, K, Ca, Mg, and S） in litter of three primarily spruce （Picea purpurea Masters） （SF）, fir （Abies faxoniana Rehder ＆ E. H. Wilson） （FF）, and birch （Betula platyphylla Sukaczev） （BF） subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter （LL） than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems.
基金the National Natural Science Foundation of China (Nos. 30471378, 90202010 and 30211130504),and the Program of 100 Distinguished Young Scientists of the Chinese Academy of Sciences.
文摘Litter production, components and dynamics were investigated and forest floor litter was quantified throughout awhole year in three subalpine forests, dominated by tree species of spruce (SF), fir (FF) and birch (BF), in WesternSichuan, China, in order to understand the key factors that influenced litter production and dynamics. Litterfall in thethree forests consisted mainly of leaves, woody litter, reproductive organs and moss. Contribution of leaf litter to thetotal litterfall was significantly (P < 0.05) greater than that of woody litter, reproductive organs or moss. Regardlessof the stands, litterfall exhibited a marked monthly variation with the maximum litterfall peaks occurring in October,with smaller peaks occurring in February for SF and FF, and May for BF. The analysis indicated that tree species,stand density, leaf area index (LAI), stand basal area and stand age were the key factors determining litter production.Meanwhile tree species and phenology controlled the litter dynamics, with wind and snow modifying the litter componentsand dynamics.
文摘The “blind-ear” as a Cu deficiency symptom in wheat on upland soils in the hilly area of Zhejiang Province was discussed in this paper.Through 3 years of field experiments,it was elucidated that “blind-ear” in wheat plant appeared due to the low level of available Cu in the soils,and the critical value 3 mg/kg for total Cu in the plant at grain filling stage and 1 mg/kg for available Cu(0.1 M HCl)in the soils.A basal dressing of 30 kg/ha of Cu sulfate to the soils could completely eliminate Cu deficiency symptoms,obtain normal grain yield and have residual effect for at least 3 years.
