The direct benefits of water retaining added by the broadleaf forest, conifer forest and China fir forest are 604. 3,428.04 and 323. 5 yuan more than that of the bare land.
Stable and dynamic light responses for net photosynthetic rate of 18 year old China fir shoots with different age and position within the tree crown were measured under optimum temperature(30±10℃) and humidity(70%±5%) for photosynthesis and normal ambient CO 2(350±10×10 -6 V/V).
The experiment indicates that the interceptive rates of China fir forest, broadleaf forest and conifer forest in summer are 9. 2%～73%, 10%～42% and 8.4%～50. 6% seperately, those in winter are 32%～66.7%,6.8%～43.8% and 23.8%～71.4%.
The charcoals derived from four other wood species showed maximum ESE values of 28?dB for Japanese cedar, 23?dB for China fir, 32?dB for red oak, and 38?dB for Taiwan acacia, respectively, at a carbonization temperature of 1100°C.
The wood species used in this study were Japanese cedar, China fir, western hemlock, red oak, fortune paulownia, and Taiwan acacia.
Furthermore, the tool geometries of 40°/5°, 50°/15° and 60°/25° produced more flow chips (weight percentage) by end-grain milling of China fir and maple.
The tool geometries of 40°/15° (sharpness of the angle-rake angle), 50°/15°, and 60°/15° for China fir and 40°/25°, 50°/5°, and 60°/5° for maple produced relatively more flow chips with parallel-to-grain milling.
The flow and thin chips were generated most often (on a weight percentage basis) for all tool angles investigated for parallel-to-grain and end-grain milling of China fir and maple.
Longitudinal stem analysis on correlation between early growth and late growth was made of over sixty China firs collected from nine main production centers in Hunan. Results indicate that: (a) It is possible to early predict the fast-growing performance of China fir. The correlation coefficients of diameter growth and height growth between 3-to 4-yr-old trees and 20-yr-old trees are significant(α=0.01 and α=0.001, respectively). (b) During the initial growth stage, if the selection differential...
Longitudinal stem analysis on correlation between early growth and late growth was made of over sixty China firs collected from nine main production centers in Hunan. Results indicate that: (a) It is possible to early predict the fast-growing performance of China fir. The correlation coefficients of diameter growth and height growth between 3-to 4-yr-old trees and 20-yr-old trees are significant(α=0.01 and α=0.001, respectively). (b) During the initial growth stage, if the selection differential is 20% in height, there will still be gains of 10% when the trees attain the age of twenty yr; and if the selection differentials are 50% in height and over 20% in diameter, gains of about 20% in height and diameter, and of over 50% in volume will be achieved at 20 yr old. (c) Different sites and production areas have a marked effect upon early predicting.
The low mountain area belongs to surplus of Tianmu mountain system. It is about 2000 square kilometres.We studied three major soil types i.e. the mountain natural soil, foot mountian natural soil and hilly cultivated soil.1) The mountian natural soil is mainly distributed on mountain slopes 80～180 m above sea level. The major soil formation is brown earthering process, and the accessary soil formation is a weakly allitic process. So, we can name the soil a yellowish-brown earth. This soil is suitable for growing...
The low mountain area belongs to surplus of Tianmu mountain system. It is about 2000 square kilometres.We studied three major soil types i.e. the mountain natural soil, foot mountian natural soil and hilly cultivated soil.1) The mountian natural soil is mainly distributed on mountain slopes 80～180 m above sea level. The major soil formation is brown earthering process, and the accessary soil formation is a weakly allitic process. So, we can name the soil a yellowish-brown earth. This soil is suitable for growing pine, China fir, bamboo, oak and Chinese sassatras, etc..2) The foot-mountain soil is located at the foot of a mountain.It is shown that the soil has lost Si and accumulated Al, Fe. But this process is not very intensive. The hydro-ferric-oxide content is dominant in soil profile,so this soil may belong to a yellow earth. It is extremely suitable for developing Chinese chestnut, common jujube, apricot, etc..3) The hilly cultivated soil is widely distributed on hilly land. It′s basic soil formation is allitie process, but it has got a cultivated process. Thus,we call this soil a cultivated yellow earth. The soil is extremely suitable for developing economic trees such as tea, oil camellia and tung oil.
Comprehensive experimental methods of the small forested catchment for studying China fir plantation ecosystems have been developed over the past five years by the Forest Ecosystem Research Station of the Central-South Forestry College. It has been methodologically inquired into that the forest ecosystem is defined as a small forested catchment with recognizable and controllable boundaries, and enclosing technique of the catchment is adopted and instruments are fully installed, so that the input, redistribution...
Comprehensive experimental methods of the small forested catchment for studying China fir plantation ecosystems have been developed over the past five years by the Forest Ecosystem Research Station of the Central-South Forestry College. It has been methodologically inquired into that the forest ecosystem is defined as a small forested catchment with recognizable and controllable boundaries, and enclosing technique of the catchment is adopted and instruments are fully installed, so that the input, redistribution and output of nutrients in the system should be precisely determined, and physical and chemical problems in the forest hydrological processes elucidated. Some data have been used for analysis and contrast. The methods and techniques can be made use of for the setting up of forest ecosystem research stations in the mountainous areas of South China.
china fir
杉木
查询“china fir”译词为用户自定义的双语例句
相关查询
2008 CNKI－中国知网