The solar energy fixation, storage and distribution of the Chinese Fir plantation in Huitong Located Ecology Station of Hunan Province were studied. The results showed that the ability of fixing solar energy in center...The solar energy fixation, storage and distribution of the Chinese Fir plantation in Huitong Located Ecology Station of Hunan Province were studied. The results showed that the ability of fixing solar energy in center area for Chinese Fir plantation was 12 474×10\+8～31 943×10\+8 J·hm\+\{-2\}, and the energy fixed by Chinese Fir plantation regularly decreased with the increasing of stand density. The distribution ratio of solar energy in stand was in order as: needle<twig<root<trunk. In evenaged forest, the reason of energy decrease with the increasing of forest density was the decrease of the solar energy accumulations of trunk, while the solar energy accumulation of twig and needle kept stably. When the forest was fully crowned, the ability of fixing solar energy decreased with the increasing of forest ages. The ability of photosynthesis decreased more quickly when the forest density was larger. When the forest density was 3 550·hm\+\{-2\} the distribution ratio of solar energy in needle was the highest at the 14th year forest, while in the 16th year forest the distribution ratio in bark was 1.91 times of that of trunk, which meant that the trunk stopped growing and the forest was on the wane. When the accessibility entering the pole stage, the forest density was the main factor which affected the solar energy fixation. Proper intermidiate was a necessary means to increase the ability of photosynthesis.展开更多
The soil thermal regime and the effect of forest harvest in the watershed were studied in virtue of thermal conductivity equation in soil and physical principle by 6 years data in Chinese Fir plantation. The results s...The soil thermal regime and the effect of forest harvest in the watershed were studied in virtue of thermal conductivity equation in soil and physical principle by 6 years data in Chinese Fir plantation. The results showed that the content of water in the soil determined the change of the thermal capacity, thermal diffusivity and thermal conductivity according to the time in the watershed. With the increasing of soil thermal capacity, the percent of solid and the decreasing of porosity, all thermal factors increased. After forest harvesting, the surface soil became more tighten because of the artificial strong disturbing. So the ratio of solid, liquid and?gas in the soil was changed and the soil thermal regimes were changed, especially the thermal diffusivity and thermal conductivity in 0～5?cm depth soil increased more than one times. The soil thermal regimes were affected by the soil structure and the soil components. But for the each factors of soil thermal regimes, the effect of each components was different, especially to the interaction of each components, which made the thermal diffusivity and thermal conductivity more complex. Therefore, it was very difficult to evaluate the effect of every soil structure and every component.展开更多
文摘The solar energy fixation, storage and distribution of the Chinese Fir plantation in Huitong Located Ecology Station of Hunan Province were studied. The results showed that the ability of fixing solar energy in center area for Chinese Fir plantation was 12 474×10\+8～31 943×10\+8 J·hm\+\{-2\}, and the energy fixed by Chinese Fir plantation regularly decreased with the increasing of stand density. The distribution ratio of solar energy in stand was in order as: needle<twig<root<trunk. In evenaged forest, the reason of energy decrease with the increasing of forest density was the decrease of the solar energy accumulations of trunk, while the solar energy accumulation of twig and needle kept stably. When the forest was fully crowned, the ability of fixing solar energy decreased with the increasing of forest ages. The ability of photosynthesis decreased more quickly when the forest density was larger. When the forest density was 3 550·hm\+\{-2\} the distribution ratio of solar energy in needle was the highest at the 14th year forest, while in the 16th year forest the distribution ratio in bark was 1.91 times of that of trunk, which meant that the trunk stopped growing and the forest was on the wane. When the accessibility entering the pole stage, the forest density was the main factor which affected the solar energy fixation. Proper intermidiate was a necessary means to increase the ability of photosynthesis.
文摘The soil thermal regime and the effect of forest harvest in the watershed were studied in virtue of thermal conductivity equation in soil and physical principle by 6 years data in Chinese Fir plantation. The results showed that the content of water in the soil determined the change of the thermal capacity, thermal diffusivity and thermal conductivity according to the time in the watershed. With the increasing of soil thermal capacity, the percent of solid and the decreasing of porosity, all thermal factors increased. After forest harvesting, the surface soil became more tighten because of the artificial strong disturbing. So the ratio of solid, liquid and?gas in the soil was changed and the soil thermal regimes were changed, especially the thermal diffusivity and thermal conductivity in 0～5?cm depth soil increased more than one times. The soil thermal regimes were affected by the soil structure and the soil components. But for the each factors of soil thermal regimes, the effect of each components was different, especially to the interaction of each components, which made the thermal diffusivity and thermal conductivity more complex. Therefore, it was very difficult to evaluate the effect of every soil structure and every component.
