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Water adaptive traits of deep-rooted C_3 halophyte(Karelinia caspica(Pall.) Less.) and shallow-rooted C_4 halophyte(Atriplex tatarica L.) in an arid region,Northwest China

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Journal of Arid Land 2012年第4期4卷 469-478页

作者： Yuan FAN PinFang LI ZhenAn HOU tusheng ren ChunLian XIONG Biao ZHANG College of Resources and Environmental Science China Agricultural University Beijing 100193 China Department of Resources and Environmental Science Shihezi University Shihezi 832000 China

This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle： Karelinia caspica （Pall.） Less. （C3, deep-rooted perennial Asteraceae grass） and Atriplex tatarica L. （C4, shallow-rooted annual Chenopodiaceae grass）. Gas exchange, leaf water potential, and growth characteristics were investigated in two growing seasons in an arid area of Xinjiang to explore the physiological adaptability of the two halophytes. Both K. caspica and A. tatarica showed midday depression of transpiration, in- dicating that they were strong xerophytes and weak midday depression types. The roots of A. tatarica were con- centrated mainly in the 0-60 cm soil layer, and the leaf water potential （~L） increased sharply in the 0-20 cm layer due to high soil water content, suggesting that the upper soil was the main water source. On the other hand, K. caspica had a rooting depth of about 1.5 m and a larger root/shoot ratio, which confirmed that this species uptakes water mainly from deeper soil layer. Although A. tatarica had lower transpiration water consumption, higher water use efficiency （WUE）, and less water demand at the same leaf water potential, it showed larger water stress impact than K. caspica, indicating that the growth of A. tatarica was restricted more than that of K. caspica when there was no rainfall recharge. As a shallow-rooted C4 species, A. tatarica displayed lower stomatal conductance, which could to some extent reduce transpiration water loss and maintain leaf water potential steadily. In contrast, the deep-rooted C3 species K. caspica had a larger root/shoot ratio that was in favor of exploiting groundwater. We concluded that C3 species （K. caspica） tapes water and C4 species （A. tatarica） reduces water loss to survive in the arid and saline conditions. The results provided a case for the phenotype theory of Schwinning and Ehleringer on halophytic plants.

关键词： Karelinia caspica Atriplex tatarica root/shoot ratio leaf water potential stomatal conductance transpiration

Soil physical quality as influenced by long-term fertilizer management under an intensive cropping system

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International Journal of Agricultural and Biological Engineering 2009年第1期2卷 19-27页

作者： Du Zhangliu Liu Shufu Xiao Xiaoping Yang Guangli ren tusheng Department of Soil and Water Sciences China Agricultural UniversityBeijing 100193China Soil and Fertilizer Institute of Hunan Province Changsha 410125China

In China’s major rice(Oryza sativa L.)production regions,the traditional fertilization modes are challenged by the continued decrease in manure and increase in mineral ***,limited information exists on the influences of long-term fertilizer management on soil organic carbon(SOC)and soil physical properties under the intensive rice production system in southern *** objective of this study was to characterize the changes of soil physical properties as related to mineral fertilizer,crop residues,and manure application based on a long-term field *** experiment,initiated in 1986,has five treatments:unfertilized,mineral fertilizer alone,rice residues plus mineral fertilizer,low manure rate plus mineral fertilizer,and high manure rate plus mineral *** cropping system consists of barley(Hordaum vulgare L.),early rice,and late rice,three crops in a *** May 2006,after barley harvest,soil samples were collected from the 0~10 cm and 10~20 cm layers to determine SOC concentration,aggregate size distribution,bulk density(rb),saturated hydraulic conductivity(Ks),and soil water characteristic curves(SWCC).The results indicated that manure significantly reducedrb,increased SOC concentration,soil aggregation,Ks,transmission and storage porosity,as well as water retention *** application of crop residue and mineral fertilizer also improved soil physical properties,but the improvement by mineral fertilizer alone was *** analysis demonstrated that S,the slope of the SWCC at its inflection point,was closely associated with the selected physical parameters,suggesting S was an effective parameter for soil physical quality ***,in applying the S-theory,a unified approach to define the residual water content should be considered.

关键词： Mineral fertilizer crop residue manure soil physical quality soil water characteristic curve S-theory

Integrated rice management simultaneously improves rice yield and nitrogen use efficiency in various paddy fields

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Pedosphere 2020年第6期30卷 863-873页

作者： Yujiao DONG Fanwen ZENG Jiang YUAN Guangbin ZHANG Yuanxue CHEN Xuejun LIU Padilla HILARIO tusheng ren Shihua LU College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China Soil and Fertilizer Institute Sichuan Academy of Agricultural SciencesChengdu 610066China Bureau of Agriculture in Shehong County Suining CitySichuan ProvinceShehong 629200China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Sichuan Agricultural University Wenjiang 611130China Kadoorie Farm and Botanic Garden Hong Kong 999077China

The hilly area of Southwest China is a typical rice production area which is limited by seasonal droughts and low temperature in the early rice growth period.A field experiment was conducted on three typical paddy fields(low-lying paddy field,medium-elevation paddy field,and upland paddy field)in this ***(N)treatment(180 kg N ha-1 year-1)was compared to a control treatment(0 kg N ha-1 year-1)to evaluate the effects of integrated rice management(IRM)on rice growth,grain yield,and N *** rice management integrated raised beds containing plastic mulch,furrow irrigation,and triangular *** comparison to traditional rice management(TRM),IRM promoted rice tiller development,with 7–13 more tillers per cluster at the maximum tillering stage and 1–6 more tillers per cluster at the end of tillering *** rice management significantly increased the rice aboveground biomass by 34.4%–109.0%in different growth periods and the aboveground N uptake by 25.3%–159.0%.Number of productive tillers significantly increased by 33.0%,resulting in a 33.0%increase in grain yield and 8.0%improvement of N use efficiency(NUE).Grain yields were significantly increased in all three paddy fields assessed,with IRM being the most important factor for grain yield and productive tiller *** of paddy field type and N level on N uptake by aboveground plants were reflected in the rice reproductive growth period,with the effects of IRM more striking due to the dry climate *** conclusion,IRM simultaneously improved rice yield and NUE,presenting a valuable rice management technique in the paddy fields assessed.

关键词： grain yield hilly area nitrogen uptake paddy field type plastic mulch traditional rice management

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不同温度下的土壤热导率模拟

农业工程学报 2009年第7期25卷 13-18页

作者：陆森任图生中国农业大学土壤与水科学系北京100193

土壤热导率是研究陆地表层水热盐耦合运动的基本物理参数。由于水汽潜热传热在高温下的显著作用,高温下的土壤热导率显著高于常温值。该研究的目的是建立能够有效预测高温下土壤热导率的模型。在气体扩散定律的基础上,该文结合常温土壤... 详细信息

土壤热导率是研究陆地表层水热盐耦合运动的基本物理参数。由于水汽潜热传热在高温下的显著作用,高温下的土壤热导率显著高于常温值。该研究的目的是建立能够有效预测高温下土壤热导率的模型。在气体扩散定律的基础上,该文结合常温土壤热导率模型,提出了一个计算高温土壤热导率的新方法。并利用热脉冲技术实际测定了不同温度、不同含水率下的土壤热导率,对新模型进行了测试验证。结果表明,Cass等的水汽运移促进因子参数依赖于土壤质地,且存在较大的不确定性。经过对该参数修正后,建立的热导率模型均能够较好地模拟出高温下的土壤热导率。

关键词：土壤热导率温度水汽运移促进因子

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测量土壤水分特征曲线的复合传感器设计

农业机械学报 2009年第5期40卷 56-58,91页

作者：任淑娟孙宇瑞任图生中国农业大学精细农业研究中心北京100083 中国农业大学资源与环境学院北京100083

为了直接获取土壤水特征曲线,在一种商品化微型张力计的基础上,设计了一种同步测量土壤水吸力与容积含水率的复合传感器。将张力计中的一段金属保护套管作为天线,利用其辐射阻抗随着土壤含水率变化的规律来测量土壤容积含水率。在实验... 详细信息

为了直接获取土壤水特征曲线,在一种商品化微型张力计的基础上,设计了一种同步测量土壤水吸力与容积含水率的复合传感器。将张力计中的一段金属保护套管作为天线,利用其辐射阻抗随着土壤含水率变化的规律来测量土壤容积含水率。在实验室环境下,利用3种不同质地土样(砂土、砂壤土、粘壤土)对复合传感器进行了试验,并与经典土壤水特征曲线测量方法(压力锅法结合砂箱法)获得的数据进行了比较。结果表明,复合传感器在3种土壤样品上获得的水分特征曲线的均方根误差均小于0.05,与标准方法所获得的结果具有较好的一致性。

关键词：土壤含水率水吸力水特征曲线复合传感器

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利用热脉冲技术测量土壤表层含水率

农业工程学报 2015年第2期31卷 72-78页

作者：张晓王月月任图生中国林业科学院荒漠化研究所北京100091 中国农业大学土壤与水科学系北京100193

准确测定表层土壤水分对陆地-大气间水热交换研究具有重要意义。由于对土壤结构影响轻微,热脉冲技术在原位监测含水率方面具有较大优越性,但目前田间应用集中在5 cm以下土层。该研究利用多针热脉冲传感器测定土壤容积热容量,然后基于热... 详细信息

准确测定表层土壤水分对陆地-大气间水热交换研究具有重要意义。由于对土壤结构影响轻微,热脉冲技术在原位监测含水率方面具有较大优越性,但目前田间应用集中在5 cm以下土层。该研究利用多针热脉冲传感器测定土壤容积热容量,然后基于热脉冲含水率法和热脉冲含水率变化法分别得到了3、9、21和39 mm的土壤含水率。结果表明,与烘干法含水率比较,热脉冲含水率变化法含水率在4个深度的均方根误差分别为0.022、0.006、0.004和0.006 m3/m3,均小于相应深度上热脉冲含水率法含水率的均方根误差。另外,热脉冲含水率变化法也降低了4个热脉冲传感器测定含水率的变异性。因此,热脉冲技术能够监测表层的土壤水分动态,表层土壤含水率的均方根误差在0.022 m3/m3以内。

关键词：土壤水分热传导热脉冲技术表层

探针有限特性对热脉冲技术测定土壤热特性的影响

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农业工程学报 2014年第19期30卷 71-77页

作者：付永威卢奕丽任图生中国农业大学土壤与水科学系北京100193

在利用热脉冲方法测定热特性时，通常对探针形状做理想化处理，即假设探针为线性热源，热导率无限大而热容量为零。在实际应用中，探针本身的有限特性（有限半径以及有限热容量）会导致热特性测定误差。为了研究探针有限特性对热脉冲技... 详细信息

在利用热脉冲方法测定热特性时，通常对探针形状做理想化处理，即假设探针为线性热源，热导率无限大而热容量为零。在实际应用中，探针本身的有限特性（有限半径以及有限热容量）会导致热特性测定误差。为了研究探针有限特性对热脉冲技术测定土壤热特性的影响，该研究采用改进的热脉冲探针（直径2mm、长度40mm、间距8mm）测定土壤热特性，并分别使用PILS（pulsed infinite line source，无限长线性脉冲热源）和ICPC（identical cylindrical perfect conductors，近似圆柱形完美导体）2种理论估计土壤热特性，比较分析了探针有限特性对热脉冲技术测定热特性结果的影响。结果表明：1）与PILS理论相比，利用ICPC理论拟合得到的温度升高曲线，可以有效减少探针有限半径和热容量对土壤热特性测定结果的影响。与ICPC理论相比，在0.03～0.25m3/m3的含水率范围内，用PILS理论得到的砂土热扩散率和热导率分别偏低11.8%和5.2%；与模拟热容量相比，PILS和ICPC理论分别将热容量高估16.1%和7.9%；2）探针有限特性对土壤热特性的影响与含水率有关：在干土上最大；随着土壤含水率的增加，其影响逐渐降低。该研究对提高热脉冲技术测定土壤热特性的准确性具有指导意义。

关键词：土壤热传递含水率土壤热特性热脉冲技术探针有限特性

利用基于偏微分方程的图像滤波技术研究土壤孔隙结构

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农业工程学报 2014年第3期30卷 78-85页

作者：华珊陈研梁露焘任图生中国农业大学资源与环境学院植物-土壤相互作用教育部重点实验室北京100193

利用自主研发的土壤切片数字图像处理分析系统软件，采用3种滤波方式，即BMO滤波（boundarymeanoscillation有界平均振荡模型）、PM滤波（Perona-Malik偏微分方程模型）和中值滤波，对免耕、翻耕和旋耕3种耕作方式下不同深度土壤切片的... 详细信息

利用自主研发的土壤切片数字图像处理分析系统软件，采用3种滤波方式，即BMO滤波（boundarymeanoscillation有界平均振荡模型）、PM滤波（Perona-Malik偏微分方程模型）和中值滤波，对免耕、翻耕和旋耕3种耕作方式下不同深度土壤切片的数字图像进行去噪增强，并对处理后的图像进行了孔隙特征参数提取与统计。在此基础上，探讨了几种图像滤波技术的效果以及耕作方式对不同土层土壤孔隙形态结构的影响，以期找到适用于土壤切片数字图像的滤波技术，为后期土壤孔隙信息的提取与统计提供工具。结果表明，采用BMO滤波后，从土壤切片数字图像得到的土壤孔隙度与试验结果最为接近；其中，孔径〈5μm的孔隙度显著大于其他图像滤波技术的结果，而5～50μm与〉50μm孔径的孔隙度与其他图像滤波技术的结果没有显著差异：与免耕相比，翻耕与旋耕提高了表层土壤的孔隙度，增加了传导孔隙的比例。

关键词：土壤图像处理模型有界平均振荡模型土壤孔隙度孔隙分布图像滤波技术

利用最小水分限制范围评价东北黑土区免耕和垄作的土壤水分稳定性

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农业工程学报 2020年第10期36卷 107-115页

作者：刘淑珍高伟达任图生中国农业大学土地科学与技术学院北京100193

为明确耕作方式对黑土土壤水分稳定性的作用,提高黑土区雨养农业对气候变化的适应性,该研究基于黑土区长期免耕定位试验,利用最小水分限制范围(Least Limiting Water Range,LLWR)评价免耕(NT)和垄作(CT)管理下土壤含水率有效性及其变异... 详细信息

为明确耕作方式对黑土土壤水分稳定性的作用,提高黑土区雨养农业对气候变化的适应性,该研究基于黑土区长期免耕定位试验,利用最小水分限制范围(Least Limiting Water Range,LLWR)评价免耕(NT)和垄作(CT)管理下土壤含水率有效性及其变异特征。结果表明:1)在0~5、>5~10、>10~20和>20~40 cm 4个土层中,NT处理显著降低了>5~10 cm的LLWR,其他3个土层LLWR差异均不显著;2)在平水年(2014)、枯水年(2015)和丰水年(2016),NT管理下作物生育期内0~40 cm平均土壤含水率正常率分别为48%、72%和85%,年间变异系数为0.23;CT的土壤含水率正常率分别为56%、20%和51%,年间变异系数为0.38;3)在丰水年,NT与CT的平均有效储水量差值最小,NT比CT高8.95mm;在枯水年相差最大,NT的平均有效储水量比CT高13.99mm。因此,NT管理下土壤水分更稳定地分布在LLWR内,在极端降雨年份(枯水年和丰水年)优势尤其明显。

关键词：土壤耕作含水率免耕降雨年型最小水分限制范围