土壤水分特征曲线模型作为实验测定土壤水分特征数据的一种替代方法,因其具有计算方便快捷和便于嵌入数值模拟程序的优点,开始受到越来越广泛的关注。虽然文献中存在众多的土壤水分特征曲线模型,但是这些模型的适用范围及拟合性能尚不...土壤水分特征曲线模型作为实验测定土壤水分特征数据的一种替代方法,因其具有计算方便快捷和便于嵌入数值模拟程序的优点,开始受到越来越广泛的关注。虽然文献中存在众多的土壤水分特征曲线模型,但是这些模型的适用范围及拟合性能尚不明确。为了获得更加准确适用的土壤水分特征曲线,在实际应用中通常需要花费大量时间和精力去测试各种模型。为了解决上述问题,在国内外研究成果的基础上收集整理了12种典型的土壤水分特征曲线模型,并利用包含不同质地、有机质含量及容重的8种土壤的实测土壤水分特征数据来评估比较这些模型的模拟性能。模型性能通过均方根误差(RMSE)、平均偏差(AD)、AIC准则(Akaike Information Criterion)和纳什效率系数(NSE)4个指标评估。研究结果表明:大部分的模型能够提供比较接近于实际的拟合结果,评价指标值也比较相近。其中,KCGS2006(包含3个参数)和K1999模型(包含2个参数)拟合效果最好,而Gregson1987(包含1个参数)的拟合效果最差。该研究可以深入了解各种土壤水分特征曲线模型的适用性与局限性,更好地为生态环境建设和农业可持续发展研究中土壤水力参数的选取提供依据和参考。展开更多
To explore the effect of biochar on alleviating plant drought stress after being applied to soil,we prepared biochar using rice straw as raw material according to different pyrolysis temperatures(400,600 and 800°...To explore the effect of biochar on alleviating plant drought stress after being applied to soil,we prepared biochar using rice straw as raw material according to different pyrolysis temperatures(400,600 and 800°C)and reaction atmosphere(CO_(2)and N_(2)).The effect of different pyrolysis conditions on the water retention performance of biochar was studied.The early high water-retaining biochar materials were selected and wheat seeds were selected for the verification experiment of returning to the field in pots.Biochar with high porosity(specific surface area and total pore volume)and more surface hydrophilic functional groups(mainly-OH and-COOH)can indeed improve soil water retention performance.It is mainly reflected in the increase in the dry weight and fresh weight of wheat and the soil moisture content in the treatment group with the addition of biochar water retention agent.Among them,the growth rates of fresh weight and dry weight of wheat in the C800 treatment group were 11.51%and 10.64%,and the soil moisture content increased by 1.89%.It is worth noting that the application of biochar cannot completely alleviate the impact of drought stress on plants,but it can reduce the amount of water irrigation to a certain extent.Considering the quality of biochar,the biochar material(C800)prepared under the pyrolysis temperature of 800°C and the reaction atmosphere of CO_(2)has high water retention performance.展开更多
文摘土壤水分特征曲线模型作为实验测定土壤水分特征数据的一种替代方法,因其具有计算方便快捷和便于嵌入数值模拟程序的优点,开始受到越来越广泛的关注。虽然文献中存在众多的土壤水分特征曲线模型,但是这些模型的适用范围及拟合性能尚不明确。为了获得更加准确适用的土壤水分特征曲线,在实际应用中通常需要花费大量时间和精力去测试各种模型。为了解决上述问题,在国内外研究成果的基础上收集整理了12种典型的土壤水分特征曲线模型,并利用包含不同质地、有机质含量及容重的8种土壤的实测土壤水分特征数据来评估比较这些模型的模拟性能。模型性能通过均方根误差(RMSE)、平均偏差(AD)、AIC准则(Akaike Information Criterion)和纳什效率系数(NSE)4个指标评估。研究结果表明:大部分的模型能够提供比较接近于实际的拟合结果,评价指标值也比较相近。其中,KCGS2006(包含3个参数)和K1999模型(包含2个参数)拟合效果最好,而Gregson1987(包含1个参数)的拟合效果最差。该研究可以深入了解各种土壤水分特征曲线模型的适用性与局限性,更好地为生态环境建设和农业可持续发展研究中土壤水力参数的选取提供依据和参考。
基金This study was supported by the National Key Research and Development Program of China(2018YFD0800703)Wuhan Science and Technology Project(2020020601012264)the Fundamental Research Funds for the Central Universities(2662018PY078).
文摘To explore the effect of biochar on alleviating plant drought stress after being applied to soil,we prepared biochar using rice straw as raw material according to different pyrolysis temperatures(400,600 and 800°C)and reaction atmosphere(CO_(2)and N_(2)).The effect of different pyrolysis conditions on the water retention performance of biochar was studied.The early high water-retaining biochar materials were selected and wheat seeds were selected for the verification experiment of returning to the field in pots.Biochar with high porosity(specific surface area and total pore volume)and more surface hydrophilic functional groups(mainly-OH and-COOH)can indeed improve soil water retention performance.It is mainly reflected in the increase in the dry weight and fresh weight of wheat and the soil moisture content in the treatment group with the addition of biochar water retention agent.Among them,the growth rates of fresh weight and dry weight of wheat in the C800 treatment group were 11.51%and 10.64%,and the soil moisture content increased by 1.89%.It is worth noting that the application of biochar cannot completely alleviate the impact of drought stress on plants,but it can reduce the amount of water irrigation to a certain extent.Considering the quality of biochar,the biochar material(C800)prepared under the pyrolysis temperature of 800°C and the reaction atmosphere of CO_(2)has high water retention performance.
