| This paper studies stand heat property,energy environment soil, which is not only stand the foundation of heat and water conditions, evaporate-transpiration,water research needs, but also to moisture,heat balance study involved such energy and material problem of the theory and method of discussion, then how to evaluate the Camphor tree plantations was to provide the theoretical basis for ecological benefit.At the same time, in order to determine the structure optimization model of heat and water area and improve the regional microclimate provide scientific basis, also be for urban forest to ease the urban heat island effect for reference, This research mainly based on the data in2010-2011and camphor trees monitoring, through fall monitoring, through fall each layer of the clearing of soil temperature observation data and soil bulk density,soil moisture content, soil particles and other factors, the determination of the secret basis. This paper analyzes the artificial monitoring, through fall camphor trees and opens the surface temperature, soil monitoring, through fall temperature,temperature gradient distribution and its fluctuation state,and the soil and soil heat flow to the changing law of hot property. Specific research results are as follows:Bare land in the Camphor forest, its year, month,daily average temperatures were higher than in the forest, especially in the stronger radiation month, he difference is most significant. In June, the average temperature of bare land in the Camphor forest is higher than in the forest by4.3℃, in December,the difference is the smallest, only by0.1℃. In the diurnal variation of the forest during the day, bare land surface temperature is significantly higher than the forest; the maximum difference is9.3℃at12:00. But from the middle night to early morning, the difference is small, and the latter is slightly higher than the former. The surface maximum daily temperature appears at12:00within the forest, while in the forest open space is at14:00. About low temperature of the forest and open land surface appeared moment, appearing at4:00in the weak radiation month (November to April) of the forest, the forest open space appears at6:00; in the strong radiation month (May to October), camphor tree forest and open land surface, the lowest temperature appears at6:00.Monthly mean of the layers of soil temperature,bare land in the Camphor forest is higher than in the forest. Annual spatial distribution of soil temperature, Follow the law that it increases with soil depth in the radiation weak month,and vice versa is followed by the law of decreasing, in March and September,appearing completely reversed distribution. Average daily soil temperature in the Camphor forest is obvious than inner. On the Average daily soil temperature, there are two completely opposite layout; Soil temperature increases with soil depth and decreases with soil depth, while bare land in the Camphor forest, This altered time took place between10:00and22:00, while the altered time took place between12:00and22:00within the forest.Due to the existence of the canopy of the forest,there are differences of the soil flow and distribution law in Camphor Forest and within the open space. Of the average daily change, bare land in the Camphor forest conduct heat to the surface below20cm from midnight to6:00, start with8:00, it conduct heat from the surface deep into the soil downstream.From18:00to24:00,5-15cm soil layer became a guide and heat transfer pooling place. In the Camphor forest,conducting heat from the land surface to the soil is also at8:00,and the case is with the bare land;18:00to24:00this time, the15cm depths of soil heat source became the upper and lower transmission heat source;2:00to8:00this time, conducting heat from the deep soil to the land surface is delayed by2hours than in the bare land.The soil porosity of the open space and within the layers of camphor forest is reducing with the increasing depth soil. Relativeto other months, the soil solid-liquid within the open spaceof each layer of camphor forest reached maximum in March and minimum in February; But in the camphor forest0-20cm solid-liquid ratios of maximum and minimum values of the four soil layers soil appeared a significant difference.Bare land in the Camphor forest,layers of soil volumetric heat capacity reaches the maximum in March, the dates are as follows:2.225,2.22,2.272and2.314J×106/m3·℃, while in February with its minimum, are as follows1.805,1.871,1.958 and1.983J×lO6/m3·℃; in the Camphor forest,the maximum of layers of soil volumetric heat capacity are as follows:2.214(November),2.154(March),2.173(March) and2.194(June) J×lO6/m3·℃while in February with its minimum1.803,1.792,1.855and1.929J×lO6/m3·℃. Bare land in the Camphor forest, the mean of soil thermal diffusivity is0.12,0.45,0.49and0.42(10-6/m2·s), while in the forest, the date is0.09,0.43,0.47and0.41(10-6/m2·s).This paper further clarified the thermal process mechanism of the Cinnamomum camphor plantation, the heat distribution of the soils as well as the variation of soil thermal properties, is of great significance to the camphor tree plantation afforestation and tending. And provided an important basis for measuring the structure of plantations. |
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