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浅谈地下室结构设计及常见环保问题
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作者 郝喜玲 《内蒙古石油化工》 CAS 2007年第3期71-72,共2页
针对一般地下室设计当中易进入的误区展开论述,经分析指出错误,提出一些建议,可工同类工程参考。
关键词 地下室 水土算法 水土分算法 带扶壁柱地下室外墙
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An improved algorithm to estimate the surface soil heat flux over a heterogeneous surface: A case study in the Heihe River Basin 被引量:1
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作者 LI NaNa JIA Li LU Jing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第7期1169-1181,共13页
Surface soil heat flux(G0) is an indispensable component of the surface energy balance and plays an important role in the estimation of surface evapotranspiration(ET). This study calculated G0 in the Heihe River Basin... Surface soil heat flux(G0) is an indispensable component of the surface energy balance and plays an important role in the estimation of surface evapotranspiration(ET). This study calculated G0 in the Heihe River Basin based on the thermal diffusion equation, using the observed soil temperature and moisture profiles, with the aim to analyze the spatial-temporal variations of G0 over the heterogeneous area(with alpine grassland, farmland, and forest). The soil ice content was estimated by the difference in liquid soil water content before and after the melting of the frozen soil and its impact on the calculation of G0 was further analyzed. The results show that:(1) the diurnal variation of G0 is obvious under different underlying surfaces in the Heihe River Basin, and the time when the daily maximum value of G0 occurs is a few minutes to several hours earlier than that of the net radiation flux, which is related to the soil texture, soil moisture, soil thermal properties, and the vegetation coverage;(2) the net radiation flux varies with season and reaches the maximum in summer and the minimum in winter, whereas G0 reaches the maximum in spring rather than in summer, because more vegetation in summer hinders energy transfer into the soil;(3) the proportions of G0 to the net radiation flux are different with seasons and surface types, and the mean values in January are 25.6% at the Arou site, 22.9% at the Yingke site and 4.3% at the Guantan site, whereas the values in July are 2.3%, 1.6% and 0.3%, respectively; and(4) G0 increases when the soil ice content is included in thermal diffusion equation, which improves the surface energy balance closure by 4.3%. 展开更多
关键词 surface soil heat flux soil ice content surface energy balance heterogeneous surfaces
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Effects of spatial distribution of soil parameters on soil moisture retrieval from passive microwave remote sensing 被引量:5
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作者 ZHANG Tao ZHANG LiXin +3 位作者 JIANG LingMei ZHAO ShaoJie ZHAO TianJie LI YunQing 《Science China Earth Sciences》 SCIE EI CAS 2012年第8期1313-1322,共10页
In this paper,we studied the effect of spatial distribution of soil parameters on passive soil moisture retrieval at pixel scale.First,we evaluated the forward microwave emission model and soil moisture retrieval algo... In this paper,we studied the effect of spatial distribution of soil parameters on passive soil moisture retrieval at pixel scale.First,we evaluated the forward microwave emission model and soil moisture retrieval algorithm accuracy through the observa-tion of field experiments.Then,we used soil parameters in different spatial distribution patterns,including random,normal,and uniform distribution,to determine the different levels of heterogeneity on soil moisture retrieval,in order to seek the rela-tionship between heterogeneity and soil moisture retrieval error.Finally,we conducted a controlled heterogeneity effect ex-periment measurements using a Truck-mounted Multi-frequency Radiometer(TMMR) to validate our simulation results.This work has proved that the soil moisture retrieval algorithm had a high accuracy(RMSE=0.049 cm3 cm 3) and can satisfy the need of this research.The simulation brightness temperatures match well with observations,with RMSE=9.89 K.At passive microwave remote sensing pixel scale,soil parameters with different spatial distribution patterns could have different levels of error on soil moisture estimation.Overall,we found that soil moisture with a random distribution in a satellite pixel scale can cause the largest error,with a normal distribution being the second,and a uniform distribution the least due to the smallest het-erogeneity. 展开更多
关键词 bare soil HETEROGENEITY spatial distribution passive microwave remote sensing soil moisture
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