干旱区生态环境知识资源中心(Arid): 不同含水率下日光温室土壤温度变化规律的峰拟合法拟合

Arid

	不同含水率下日光温室土壤温度变化规律的峰拟合法拟合
其他题名	Peak-fitting based prediction of soil temperature according to soil moisture content in solar greenhouse
	塔娜; 五十六; 马文娟; 陈斌; 朱英开
来源期刊	农业工程学报
ISSN	1002-6819
出版年	2014
卷号	30 期号:20 页码:204-210
中文摘要	为了探讨中国西北寒冷干旱地区冬季日光温室内土壤含水率和温度变化规律,该文对内蒙古呼和浩特市日光温室内土壤温度和含水率进行了测试,并利用峰拟合法对不同含水率下的土壤温度进行了拟合。试验表明,在强蒸发条件下,随着土壤温度的升高,土壤非饱和导水率提高,从而将干湿发生面下方的液态水引入干湿发生面。峰拟合函数的最小拟合度为0.95907。通过计算得知,降低含水率能提高白天和夜间的土壤平均温度。验证估计Extreme函数得知,只要确定偏移y_0、中心chi_c、宽度w、幅值A即可得土壤温度对时间的变化函数。该方法可以有效地减少测试点的数量,并把离散的数据点转化为连续函数从而进行微积分分析,提高检测效率。
英文摘要	Soil temperature and moisture directly impact on the root growth and seed germination of crops in greenhouse in cold area. Decreasing of soil moisture content would be beneficial for increasing soil temperature in greenhouse during cold situations. Considering low soil temperature that restricts activities of microorganisms in soil, optimizing of soil moisture content is essential to keep balance between soil temperature and activity of soil microorganisms. The objective of this research was to determine the authentic relationship between soil temperature and moisture content in greenhouse by establishing and validating of a soil temperature variation with soil moisture content equation using peak fitting analysis. All the works were carried out in a typical solar greenhouse from Dec 20, 2013 to Feb 20, 2014. We designed four test zones (2 m*2 m each) in the central part of the greenhouse, namely zone I (irrigated 10 h ago), zone II (irrigated 8 d ago), zone III (irrigated 33 d ago), and zone IV (control). To monitor the soil temperature, three soil moisture/temperature sensors were placed in soil of each test zone with 0, 15 and 30cm depth, respectively. For control zone, a soil moisture/temperature sensor was placed on the soil surface (0 cm). We tested the moisture content and temperature variations of different soil depth. According to a Single Peak Fitting Module (PEM), we obtained the Extreme Fitting Function of the diurnal change of soil temperature. The relationship between temperature-variation equation and the moisture content was determined by calculating the area under temperature-variation curve and analyzing coefficients of the equation. The extreme function which has specific physical meaning of parameters was named as Estimated Extreme function. The reliability and validity of Peak Fitting Method were confirmed by error analysis of certain moisture content in different weather condition on the surface of the control plot. We investigated the change of soil temperature under different moisture content in greenhouse by using Peak Fitting Method. The results showed that the condition of strong evaporation can increase soil temperature and resulted in enhancing of unsaturated hydraulic conductivity of soil and the suction on wet evaporate face, leading to increase of liquid water level to the dry-wet surface. Using this method to simulate the temperature variation curve, the minimum matching degree was 0.9590. Based on the calculation of enveloping area of temperature curve, we obtained the average soil temperature and found out that decrease of soil moisture content caused an increase of average temperature of soil in both day and night. According to the coefficients of fitting equation established by the data from sunny day, we found that amplitude, center and widthfactors decreased while offset substantially increased along with the decrease of soil moisture content on the soil surface. However, offset, center and width factors increased while amplitude decreased in soil at 15 cm depth, and all four factors increased in the soil at 30 cm depth when the soil moisture content decreased. These results indicated that drop of soil moisture content can result in decrease of the regenerative capacity of soil and content of liquid water, and down shift of dry-wet surface. Validation results showed that the minimal discrepancy of temperature was 0.71℃, implying that the four factors of Estimated Extreme function were good enough to calculate the change of soil temperature. The method developed in this work is able to improve the efficiency by decreasing the measurement of soil temperature and convert the discrete data points into a continuous function.
中文关键词	温室 ; 含水率 ; 土壤 ; 温度峰拟合法
英文关键词	greenhouses moisture content soils temperature peak fitting module
类型	Article
语种	中文
收录类别	CSCD
WOS类目	Agriculture
CSCD记录号	CSCD:5294573
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/378820
作者单位	塔娜, 内蒙古农业大学机电工程学院, 呼和浩特, 内蒙古 010018, 中国.; 五十六, 内蒙古农业大学机电工程学院, 呼和浩特, 内蒙古 010018, 中国.; 马文娟, 内蒙古农业大学机电工程学院, 呼和浩特, 内蒙古 010018, 中国.; 陈斌, 内蒙古农业大学机电工程学院, 呼和浩特, 内蒙古 010018, 中国.; 朱英开, 内蒙古农业大学机电工程学院, 呼和浩特, 内蒙古 010018, 中国.
推荐引用方式 GB/T 7714	塔娜,五十六,马文娟,等. 不同含水率下日光温室土壤温度变化规律的峰拟合法拟合[J],2014,30(20):204-210.
APA	塔娜,五十六,马文娟,陈斌,&朱英开.(2014).不同含水率下日光温室土壤温度变化规律的峰拟合法拟合.农业工程学报,30(20),204-210.
MLA	塔娜,et al."不同含水率下日光温室土壤温度变化规律的峰拟合法拟合".农业工程学报 30.20(2014):204-210.