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Effect of continuous negative pressure water supply on the growth, development and physiological mechanism of Capsicum annuum L.

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Journal of Integrative Agriculture 2017年第9期16卷 1978-1989页

作者： LI Di long huai-yu ZHANG Shu-xiang WU Xue-ping SHAO Hong-ying WANG Peng Agronomy College Heilongjiang Bayi Agricultural University Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

Effects of continuous negative pressure water supply on water consumption, growth and development, as well as physiological mechanism and quality of Capsicum annuum L. were investigated in this paper. Meanwhile, the optimal negative pressure water supply conditions for growth of C. annuum L. were screened out to achieve the goals of water conservation, high yield and high quality, thus providing theoretical foundation for its field production. The pot experiment within the greenhouse was utilized; the continuous negative pressure water supply was adopted; the four treatments, artificial watering（CK）, –5 k Pa（T1）, –10 k Pa（T2）, and –15 k Pa（T3） were set; and the daily water consumption, yield, as well as the biomass, nitrate reductase, root activity, vitamin C, capsaicin, and nutrient uptakes of nitrogen（N）, phosphorus（P） and potassium（K） during various stages of its growth were determined. Compared with CK, when the water supply pressure was controlled at –5 to –15 k Pa in the experiment, the total water consumption of C. annuum L. reduced by 53.42 to 67.75%, the total water consumption intensity reduced by 54.29 to 67.14%, and the water use efficiency increased by 12.66 to 124.67%. The N accumulation in a single strain of C. annuum L. from the color turning stage to the red ripe stage increased by 15.99 to 100.55%, respectively, compared with that of CK; the P accumulation increased by 20.47 to 154.00% relative to that of CK, and the K accumulation increased by 64.92 to 144.9% compared with that of CK. Compared with CK, C. annuum L. yield was remarkably improved by 13.79% at T1, and contents of vitamin C, capsaicin as well as carotenoids at all growth stages were enhanced by 13.42–147.01%, 11.54–71.01%, and 41.1–568.06%, respectively. Nitrate reductase activity, root activity and chlorophyll（a＋b） were markedly increased by 335.78–500%, 79.6–140.68% and 114.95–676.19%, respectively, from immature stage to full ripe stage. Adopting the continuous negative pressure wa

关键词： negative pressure water supply Capsicum annuum L. physiological indexes yield quality

Spatio-temporal variations in organic carbon density and carbon sequestration potential in the topsoil of Hebei Province, China

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Journal of Integrative Agriculture 2016年第11期15卷 2627-2638页

作者： CAO Xiang-hui long huai-yu LEI Qiu-liang LIU Jian ZHANG Ji-zong ZHANG Wen-ju WU Shu-xia Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Pasture Systems and Watershed Management Research Unit USDA-Agricultural Research ServiceUniversity Park

Reliable prediction of soil organic carbon（SOC） density and carbon sequestration potential（CSP） plays an important role in the atmospheric carbon dioxide budget. This study evaluated temporal and spatial variation of topsoil SOC density and CSP of 21 soil groups across Hebei Province, China, using data collected during the second national soil survey in the 1980 s and during the recent soil inventory in 2010. The CSP can be estimated by the method that the saturated SOC content subtracts the actual SOC associated with clay and silt. Overall, the SOC density and CSP of most soil groups increased from the 1980 s to 2010 and varied between different soil groups. Among all soil groups, Haplic phaeozems had the highest SOC density and Endogleyic solonchaks had the largest CSP. Areas of soil groups with the highest SOC density（90 to 120 t C ha^（–1）） and carbon sequestration（120 to 160 t C ha^（–1）） also increased over time. With regard to spatial distribution, the north of the province had higher SOC density but lower CSP than the south. With respect to land-use type, cultivated soils had lower SOC density but higher CSP than uncultivated soils. In addition, SOC density and CSP were influenced by soil physicochemical properties, climate and terrain and were most strongly correlated with soil humic acid concentration. The results suggest that soil groups（uncultivated soils） of higher SOC density have greater risk of carbon dioxide emission and that management should be aimed at maximizing carbon sequestration in soil groups（cultivated soils） with greater CSP. Furthermore, soils should be managed according to their spatial distributions of SOC density and carbon sequestration potential under different soil groups.

关键词： carbon sequestration SOC density spatial variation topsoil

负压灌溉提高紫叶生菜的水分利用效率和根际微生物多样性

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植物营养与肥料学报 2019年第8期25卷 1434-1440页

作者：高翔张淑香龙怀玉中国农业科学院农业资源与农业区划研究所

【目的】针对目前设施农业中常用的灌溉方式容易造成土表水分蒸发和水肥流失,且不能按照作物所需自动供水供肥的现状,本研究探讨了负压灌溉提高紫叶生菜的产量和品质,以及水分利用效率和土壤微生物群落多样性的机理。【方法】在温室内... 详细信息

【目的】针对目前设施农业中常用的灌溉方式容易造成土表水分蒸发和水肥流失,且不能按照作物所需自动供水供肥的现状,本研究探讨了负压灌溉提高紫叶生菜的产量和品质,以及水分利用效率和土壤微生物群落多样性的机理。【方法】在温室内进行盆栽试验,以紫叶生菜(Lactuca sativa L.)为试验材料,设置3个灌溉处理:常规灌溉、滴灌和负压灌溉。收获后,测定了紫叶生菜的产量,分析了品质(维生素C、可溶性糖、花青素和硝酸盐含量),植株的养分(氮、磷和钾)浓度和吸收量,监测了土壤水分含量动态的变化,计算了水分消耗量和水分利用效率,分析了根际土壤微生物的多样性指数和细菌在门分类上的群落结构组成。【结果】负压灌溉下显著提高紫叶生菜的产量和品质,负压灌溉比常规和滴灌处理的产量分别显著提高了68.1%和29.0%,也提高了维生素C、可溶性糖和花青素的含量,减少了硝酸盐含量。与常规灌溉相比负压灌溉显著提高了紫叶生菜氮、磷、钾的浓度和含量,分别提高13.0%、14.4%、38.4%和90.2%、92.6%、135.5%。紫叶生菜在负压灌溉下耗水量最少,为9900 cm3,比常规和滴灌处理分别减少了23.8%和23.8%;负压下水分利用效率比常规和滴灌分别显著提高了122.2%和70.5%。同时负压灌溉处理下动态的土壤含水量处于10.3%~11.3%之间,变异范围低于常规和滴灌处理9.2%~11.6%。通过高通量测序紫叶生菜根际土壤微生物群落发现,负压灌溉处理下微生物多样性指数最高,表现为OTU、Chao1和Shannon指标的数值显著高于常规和滴灌处理,其数值分别为1808、2437和8.48,分别比常规灌溉处理显著提高了15.2%、15.7%和3.16%。同时也改变了细菌在门分类水平上组成的相对丰度,在负压灌溉处理下比常规和滴灌处理分别提高了放线菌门(Actinobacteria),绿弯菌门(Chloroflexi),疣微菌门(Verrucomicrobia)和浮霉菌门(Planctomycetes)在细菌门分类上的相对丰度。【结论】本试验证明了负压灌溉系统通过土壤水肥平稳供应机制,实现了紫叶生菜高产优质且高效利用水分的目标。因此,负压灌溉系统相比常规和滴灌,显著提高了紫叶生菜的产量和品质、水分利用效率和根际微生物群落的多样性,为设施农业的可持续性发展提供科学依据。

关键词：紫叶生菜负压灌溉产量和品质水分利用效率根际微生物群落

我国不同产品认证体系农产品产地环境标准的比较

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生态与农村环境学报 2015年第5期31卷 625-632页

作者：冀宏杰张怀志龙怀玉岳现录中国农业科学院农业资源与农业区划研究所/农业部植物营养与养分循环重点开放实验室北京100081

产地环境对农产品质量具有重要而直接的作用,不同作物类型、不同质量管理体系都对农产品的产地环境提出了不同要求。应用比较研究的方法,从标准的分布状况、环境要素检测指标体系以及检测指标的限值3个方面入手,系统分析了我国国家标准... 详细信息

产地环境对农产品质量具有重要而直接的作用,不同作物类型、不同质量管理体系都对农产品的产地环境提出了不同要求。应用比较研究的方法,从标准的分布状况、环境要素检测指标体系以及检测指标的限值3个方面入手,系统分析了我国国家标准以及行业标准中对普通农产品、绿色食品、无公害食品和有机产品产地环境的要求,明确了3种体系农产品产地环境检测指标的异同。结果表明:无公害食品产地环境标准数量最多,涉及农作物门类齐全,标准级别系列完备,绿色食品标准较少,有机产品尚无专门针对产地环境的标准,而是采用一般农产品标准;对产地环境要求的严格程度比较而言,绿色食品最高,无公害食品次之,有机产品/一般农产品最低;进一步对环境3要素的比较结果显示,3种体系对土壤质量的要求差异最大,灌溉水质量次之,对空气质量的要求差异最小。探讨了当前标准制定中存在的检测指标名称和单位不统一、不同标准间的衔接性差以及有机产品产地环境等问题,以期为我国正在进行的有机产品产地环境优势区域划分以及各类农产品产地环境标准的修订提供参考。

关键词：农产品产地环境标准有机产品无公害食品绿色食品

The complex effects of miR-146a in the pathogenesis of Alzheimer's disease

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Neural Regeneration Research 2025年第5期20卷 1309-1323页

作者： yunfan long Jiajia Liu yu Wang Haidong Guo Guohong Cui Department of Neurology Shanghai No.9 People’s HospitalShanghai Jiaotong University School of MedicineShanghaiChina Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina School of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina Department of Neurology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghaiChina

Alzheimer's disease is a neurodegenerative disorder characterized by cognitive dysfunction and behavioral *** plaques formed through the extracellular deposition of amyloid-βproteins,as well as neurofibrillary tangles formed by the intracellular deposition of hyperphosphorylated tau proteins,comprise two typical pathological features of Alzheimer's *** symptomatic treatment,there are no effective therapies for delaying Alzheimer's disease ***(miR)are small,non-coding RNAs that negatively regulate gene expression at the transcriptional and translational levels and play important roles in multiple physiological and pathological ***,miR-146a,a NF-κB-regulated gene,has been extensively implicated in the development of Alzheimer's disease through several *** has demonstrated substantial dysregulation of miR-146a both during the initial phases and throughout the progression of this *** R-146a is believed to reduce amyloid-βdeposition and tau protein hyperphosphorylation through the TLR/IRAK1/TRAF6 pathway;however,there is also evidence supporting that it can promote these processes through many other pathways,thus exacerbating the pathological manifestations of Alzheimer's *** has been widely reported that miR-146a mediates synaptic dysfunction,mitochondrial dysfunction,and neuronal death by targeting m RNAs encoding synapticrelated proteins,mitochondrial-related proteins,and membrane proteins,as well as other *** the impact on glial cells,miR-146a also exhibits differential *** one hand,it causes widespread and sustained inflammation through certain pathways,while on the other hand,it can reverse the polarization of astrocytes and microglia,alleviate neuroinflammation,and promote oligodendrocyte progenitor cell differentiation,thus maintaining the normal function of the myelin sheath and exerting a protective effect on *** this review,we provide a

关键词： Alzheimer's disease amyloid-β glial cells microRNAs miR-146a neuroinflammatory

负压灌溉下施钾促进紫叶生菜生长和根际微生物多样性的研究

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中国土壤与肥料 2019年第6期 149-153页

作者：高翔张淑香龙怀玉中国农业科学院农业资源与农业区划研究所

在温室中利用负压灌溉装置进行盆栽试验,研究了施钾水平对紫叶生菜的产量、品质、养分吸收、钾肥利用效率、抗氧化能力和根际微生物多样性等指标的影响。结果表明:1)施用钾肥量为300 kg/hm^2时紫叶生菜的产量、品质和营养吸收量高于其... 详细信息

在温室中利用负压灌溉装置进行盆栽试验,研究了施钾水平对紫叶生菜的产量、品质、养分吸收、钾肥利用效率、抗氧化能力和根际微生物多样性等指标的影响。结果表明:1)施用钾肥量为300 kg/hm^2时紫叶生菜的产量、品质和营养吸收量高于其他处理。2)施肥量300 kg/hm^2处理在钾肥贡献率、钾肥农学利用率和钾肥吸收利用率表现最佳。3)225 kg/hm^2和300 kg/hm^2处理的抗氧化能力要高于其他处理。4)300 kg/hm^2处理在OTU、Chao 1和香农指数数值最好,比150 kg/hm^2处理分别高出了17%、16%和4%。综合各项指标考虑,在负压灌溉水肥一体化装置下钾肥施用量在300 kg/hm^2时,提高了紫叶生菜的产量和品质,促进养分的吸收和抗氧化能力,显著提高了钾肥的利用率和根际土微生物的多样性。

关键词：紫叶生菜负压灌溉钾肥产量和品质微生物多样性

连续负压供水对玉米氮素吸收、叶片硝酸还原酶活性及根际氮素供应的影响

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植物营养与肥料学报 2023年第8期29卷 1411-1422页

作者：张吉立冀金凤龙怀玉王鹏黑龙江八一农垦大学黑龙江大庆163319 大庆职业学院黑龙江大庆163255 中国农业科学院农业资源与农业区划研究所北京100081

【目的】分析连续负压供水下玉米的氮素吸收和叶片硝酸还原酶活性(NR)及根际土壤碱解氮和脲酶活性的影响,为提高负压供水效率提供理论依据。【方法】连续负压供水田间试验于2019和2020年在黑龙江八一农垦大学试验基地开展,供试玉米品种... 详细信息

【目的】分析连续负压供水下玉米的氮素吸收和叶片硝酸还原酶活性(NR)及根际土壤碱解氮和脲酶活性的影响,为提高负压供水效率提供理论依据。【方法】连续负压供水田间试验于2019和2020年在黑龙江八一农垦大学试验基地开展,供试玉米品种为‘先玉335’。以常规浇灌为对照(CK),设置3个负压供水压力处理:−5 kPa、−10 kPa、−15 kPa,分析了不同生育时期玉米根、茎、叶、苞叶、穗轴和籽粒氮吸收量、叶片硝态氮含量和NR活性、玉米生物量和产量,同时测定了土壤含水量、根际土壤碱解氮含量和脲酶活性。【结果】在玉米各生育期,−5 kPa处理与CK土壤含水量无显著差异,而−10 kPa和−15 kPa处理显著低于CK;在玉米成熟期,根系、地上部生物量和籽粒产量以−5 kPa处理最高,与CK相比,2019年分别提高了72.67%、24.81%和38.74%,2020年地上部生物量和籽粒产量分别提高了13.30%和16.21%,而−10 kPa和−15 kPa处理显著低于CK。与CK相比,−5 kPa处理促进了玉米对氮的吸收和利用,2019年根、茎、叶、穗轴和籽粒氮吸收量比CK分别提高了24.92%、24.86%、32.01%、18.07%和16.77%,2020年分别提高了8.27%、85.01%、30.13%、18.07%和16.77%;而−10 kPa和−15 kPa处理降低了各部位和总氮吸收量。−5 kPa处理较CK显著提高了玉米叶片硝态氮含量和NR活性,而−10 kPa和−15 kPa处理显著降低了抽雄期和成熟期叶片硝态氮含量和NR活性。在−5 kPa处理下,根际土壤碱解氮含量在拔节期至大喇叭口期与CK无显著差异,2019年抽雄期至成熟期显著低于CK 10.08%和20.91%,2020年分别低25.88%和31.93%;而−10 kPa处理,特别是−15 kPa处理均显著高于CK。−5 kPa处理根际土脲酶活性整个玉米生育期均显著低于CK,2019年拔节期、大喇叭口期、抽雄期、成熟期分别降低了14.12%、20.44%、23.59%和15.53%,2020年大喇叭口期、抽雄期和成熟期分别降低了23.12%、32.01%和27.99%,而−10 kPa和−15 kPa处理始终高于或者与CK持平。【结论】连续负压供水−5 kPa可维持整个生育期与常规供水接近的土壤水分,显著提高玉米叶片硝态氮含量和硝酸还原酶活性,促进玉米根、茎、叶、穗轴和籽粒对氮的吸收和利用,提高总氮吸收量,降低根际土碱解氮含量和脲酶活性。而−10 kPa和−15 kPa不能满足玉米的水分供应,不利于玉米的生长和氮素吸收。

关键词：氮吸收硝酸还原酶土壤氮玉米连续负压供水

Sporadic E responds to the 2022 Tonga volcano eruptions recorded by the Meridian Project

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Earth and Planetary Physics 2025年第1期9卷 20-28页

作者： YangYi Sun Tao yu Jin Wang Chi long School of Geophysics and Geomatics China University of Geosciences(Wuhan)Wuhan 430047China School of Physics and Electronic Science Guizhou Normal UniversityGuizhou 550001China

In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe atmospheric disturbances caused by the Tonga volcanic eruptions on January 15,*** most prominent signature was the disappearance of the layer after~10:00 UT over Wuhan and Fuke,which was attributed to the vertical drift caused by the *** occurred intermittently after 13:00 UT following the arrival of the tropospheric Lamb *** examine the causal mechanism for the intermittence,we also included data of horizontal winds in the mesosphere and lower thermosphere region recorded by the meteor radars at Wuhan and Mohe in this *** wind disturbances with periods of~20 hours contributed to the formation of the layer in the nighttime on January 15.

关键词： sporadic E Tonga eruptions neutral wind disturbances

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褐土和潮土K^+吸附动力学研究

土壤学报 2000年第4期37卷 563-568页

作者：龙怀玉蒋以超李韵珠中国农业大学资源和环境学院北京100094

土壤中钾离子的去向取决于不同形态钾之间的动态平衡，由于植物吸收的钾主要直接来源于土壤溶液钾，因此研究土壤对钾的吸附、解吸附动力学尤其重要。自八十年代以来，国外对此进行了较多的研究［1～5］，国内一些学者也做了一定的工... 详细信息

土壤中钾离子的去向取决于不同形态钾之间的动态平衡，由于植物吸收的钾主要直接来源于土壤溶液钾，因此研究土壤对钾的吸附、解吸附动力学尤其重要。自八十年代以来，国外对此进行了较多的研究［1～5］，国内一些学者也做了一定的工作［6，7］。然而前人的研究中，土壤往往经过一定的预处理，被制成某种离子（一般是钙离子或镁离子）的饱和土壤，显然其研究结果不能代表土壤的自然过程。只经过水淋洗的土壤其性状较接近土壤的自然性状，为此本文将研究只经过去离子水淋洗的土壤的钾吸附动力学特征。

关键词：潮土褐土钾吸附动力学动力学方程适用性土壤性质