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2000-2020年新疆阿克苏地区土地覆被变化的研究

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中国农业科技导报 2024年第8期26卷 172-179页

作者：李云罗长莲武红旗柴仲平盛建东冯雷新疆农业大学资源与环境学院新疆土壤与植物生态过程自治区实验室乌鲁木齐830052 新疆种植业绿色生产工程技术研究中心乌鲁木齐830000

为解析阿克苏地区土地覆被变化及其影响因素,采用土地利用转移矩阵和景观格局分析法,通过解译遥感影像绘制了不同年份的土地覆被变化现状图。结果表明,阿克苏地区的土地利用类型发生了显著变化。2000-2020年,阿克苏地区的耕地和城乡、... 详细信息

为解析阿克苏地区土地覆被变化及其影响因素,采用土地利用转移矩阵和景观格局分析法,通过解译遥感影像绘制了不同年份的土地覆被变化现状图。结果表明,阿克苏地区的土地利用类型发生了显著变化。2000-2020年,阿克苏地区的耕地和城乡、居民工矿用地明显增多,其他类型的用地逐渐减少;同期气候呈暖干特点。相关性分析表明,不同年份的景观格局指数与6类用地面积的相关性存在一定差异:斑块数量与地类面积的相关性由2000年的0.6下降至2020年的0.3;景观分割指数与不同类型用地面积的相关性由2000年的0.6上升至2020年的0.9。草地向未利用地转移6255 hm^(2),耕地向草地转移最多为3706.16 hm^(2),未利用地向草地转移11848.8 hm^(2)。景观格局分析表明,该区域景观呈现破碎化,土地承载力下降,抵抗生态风险的能力减弱。

关键词：土地覆被变化土地利用类型景观格局降水

^(15)N同位素标记氮肥减施棉田养分利用效率分析

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新疆农业科学 2024年第1期61卷 34-41页

作者：成志慧李红梅赵红梅涂永峰宋海英盛建东新疆农业大学资源与环境学院/新疆土壤与植物生态过程重点实验室乌鲁木齐830052 新疆慧尔农业集团股份有限公司新疆昌吉831100

【目的】研究氮肥减施对棉花氮素吸收、转运及利用效率的影响,为绿洲滴灌棉田氮肥合理施用提供参考依据。【方法】利用^(15)N同位素示踪技术,采用盆栽试验,设置不施氮肥(N_(0))、氮肥减施(N_(1),225 kg/hm^(2))、当地推荐施肥(N 2,300 k... 详细信息

【目的】研究氮肥减施对棉花氮素吸收、转运及利用效率的影响,为绿洲滴灌棉田氮肥合理施用提供参考依据。【方法】利用^(15)N同位素示踪技术,采用盆栽试验,设置不施氮肥(N_(0))、氮肥减施(N_(1),225 kg/hm^(2))、当地推荐施肥(N 2,300 kg/hm^(2))3个处理,研究氮肥减施对棉花生物量、氮素吸收量、肥料氮吸收量以及氮肥利用率的影响。【结果】氮肥减施处理的棉花干物质积累量和氮素吸收量均显著高于不施氮处理(N_(0)),而与当地推荐施肥处理差异均不显著;氮肥减施处理棉花壳、籽的干物质量和籽的氮素吸收量均显著高于当地推荐施肥处理,分别增加了7.02%、6.81%和16.59%;2个施肥处理棉籽的肥料氮(^(15)N)积累量占比最高,占全株的26.02%~35.99%,其次为叶(22.40%~23.81%)和茎(14.48%~18.98%),絮中最少(3.05%~6.62%);氮肥减施处理生殖器官的肥料氮吸收量比当地推荐施肥处理高19.02%;2个施肥处理的棉株吸收的氮素来源于肥料氮的比例(Ndff%)为21.14%~21.70%;氮肥减施处理的氮肥利用率和表观利用率均显著高于当地推荐施肥处理,分别增加2.36%和3.12%。【结论】氮肥减施(225 kg/hm^(2))可以显著提高棉籽中的干物质量、氮素吸收量、肥料氮(^(15)N)吸收量、Ndff%以及棉花整株的氮肥利用率,在确保棉花产量不降低的前提下,适度的减少化肥施用量是提高化肥利用率最有效的措施之一。

关键词：棉花 ^(15)N示踪技术氮素吸收量肥料氮(^(15)N)吸收量氮肥利用率

生物炭和有机肥配施对土壤养分影响的研究进展

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中国农学通报 2024年第2期40卷 42-51页

作者：马丹妮盛建东张坤毛洁菲常松王耀锋新疆农业大学资源与环境学院/新疆土壤与植物生态过程重点实验室乌鲁木齐830052 新疆大学生态与环境学院乌鲁木齐830017 中国科学院新疆生态与地理研究所乌鲁木齐830011 中国科学院中亚生态与环境研究中心乌鲁木齐830011

为了解决单施有机肥在用量、肥效以及养分淋失方面并同时提高土壤养分利用效率等问题,以“生物炭”、“堆肥”“生物炭有机肥配施”、“土壤性质”、“农作物养分”等为关键词,在Web of Science、Google Scholar、中国知网等网站搜索相... 详细信息

为了解决单施有机肥在用量、肥效以及养分淋失方面并同时提高土壤养分利用效率等问题,以“生物炭”、“堆肥”“生物炭有机肥配施”、“土壤性质”、“农作物养分”等为关键词,在Web of Science、Google Scholar、中国知网等网站搜索相关文献归纳并总结。结果表明:(1)生物炭能够改善堆肥的腐熟程度,增加微生物群落的丰度,降低有机肥中养分流失的风险,从而有效减少传统的堆肥对环境的影响;(2)生物炭和有机肥配施后,可提高土壤含水量,并对不同类型土壤的有效磷、速效钾含量均有不同程度地提高。同时,还能为土壤中的生物和微生物提供更好的生活物质及环境;(3)二者配合施用可以增加农作物的产量,改善其氮、磷、钾含量,但不同农作物对其响应不同。生物炭与有机肥配合施用,对提升土壤肥力和植物养分含量具有良好的效果,其效果随施用比例、土壤类型、农作物种类等因素的不同而异。本研究可对畜禽粪便资源在农业生产中的高效利用提供参考。

关键词：有机肥生物炭配施养分含量土壤养分

Tiered clustering-based management architecture in mega-satellite networks

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Science China(Information Sciences) 2024年第5期67卷 215-227页

作者： Qi HAO Di ZHOU Min sheng Yan SHI jiandong LI State Key Laboratory of Integrated Service Networks Xidian University

Hybrid orbital networking and the proliferation of satellites raise explosive management complexity in mega-satellite networks(MSNs) and prompt the management architecture to the hierarchy. In this regard, we propose a tiered clustering-based management architecture(TCMA) to realize the high-efficient and low-cost management performance. Specifically, based on the constrained satellite coverage, we derive an expression of the mapping relationship between the required control overhead of the controller interaction,the average path length of the proposed TCMA, and the corresponding number of management tiers and cluster size. The expression can determine the optimal number of tiers of the TCMA by minimizing the required flow table size between controllers, while ensuring high transmission efficiency. We then exhibit the elasticity of the hierarchical TCMA by adding the peer connections at the second-highest management tier to reduce maximum redundant paths. Simulation results verify the effectiveness of the proposed TCMA and illustrate that a 3-tier TCMA is sufficient for thousands of satellites.

关键词： mega-satellite networks hierarchical architecture average hop tiered structure clustering

Active components of Dengzhan shengmai ameliorate cognitive impairment by facilitating hippocampal long-term potentiation via the NMDA receptor-mediated Ca^(2+)/CaMKII pathway

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Journal of Pharmaceutical Analysis 2024年第3期14卷 435-438页

作者： Congyu Ma Ning sheng Jun Wu Lulu Wang jiandong Jiang Haibo Yu Jinlan Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100050China

Abnormal synaptic plasticity causes cognitive *** long-term potentiation(LTP)is a critical synaptic plasticity process[1].Rescuing impaired LTP is challenging;hence,novel agents are required for LTP *** medicine Dengzhan shengmai(DzSM)has shown notable clinical efficacy against cognitive deficits[2].However,it remains unclear how DzSM modulates *** previous study[3]revealed the influence of DZSM on glutamatergic and GABAergic synapses following chronic cerebral hypoperfusion(CCH),which motivated us to assess how DzSM affects synaptic functions.

关键词： impaired impairment hence

Selectively T cell phosphorylation activation of azvudine in the thymus tissue with immune protection effect

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Acta Pharmaceutica Sinica B 2024年第7期14卷 3140-3154页

作者： Ning sheng Rui Li Yang Li Zhe Wang Lulu Wang Yuhuan Li Jinlan Zhang jiandong Jiang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Thymus is the important immune organ,responsible for T cell development and *** lower circulating T counts have been observed in patients who died from COVID-19 compared with ***,also known as FNC,is a thymus-homing anti-SARS-CoV-2 drug in treating COVID-19 *** this study,single-cell transcriptome,proteomics,and parallel reaction monitoring(PRM)were applied to insight into the activation process of FNC in rat and SARS-CoV-2 rhesus monkey *** results indicated that thymic immune cells possess a robust metabolic capacity for cytidine-analogue drugs such as *** enzymes involved in the FNC phosphorylation process,such as Dck,Cmpk1,and Nme2,were highly expressed in CD4+ T cells,CD8+ T cells,and DP(CD4+ CD8+)***,FNC could upregulate multiple phosphorylated kinases in various cell types while downregulating the phosphatases,phosphoribosyl transferases,and deaminases,*** robust phosphorylation capacity of the thymus for cytidine analogue drug FNC,and the activation effect of FNC on the NAs metabolism system potentially contribute to its enrichment in the thymus and immune protection *** suggests that it is crucial to consider the expression level of phosphorylation kinases when evaluating NA drug properties,as an important factor during antiviral drug design.

关键词： Azvudine T cell Thymus Phosphorylation activation Nucleoside analogue

Relationship of species diversity between overstory trees and understory herbs along the environmental gradients in the Tianshan Wild Fruit Forests, Northwest China

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Journal of Arid Land 2020年第4期12卷 618-629页

作者： CHENG Junhui SHI Xiaojun FAN Pengrui ZHOU Xiaobing sheng jiandong ZHANG Yuanming Xinjiang Key Laboratory of Soil and Plant Ecological Processes College of Grassland and Environmental SciencesXinjiang Agricultural UniversityUrumqi 830052China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

In forest ecosystems, interactions between overstory trees and understory herbs play an important role in driving plant species diversity. However, reported links between overstory tree and understory herb species diversity have been inconsistent, due to variations in forest types and environmental conditions. Here, we measured species richness(SR) and diversity(Shannon-Wiener(H') and Simpson's(D) indices) of overstory trees and understory herbs in the protected Tianshan Wild Fruit Forest(TWFF), Northwest China, to explore their relationships along the latitudinal, longitudinal, elevational, and climatic(current climate and paleoclimate) gradients in 2018. We found that SR, and H' and D diversity indices of overstory trees and understory herbs exhibited a unimodal pattern with increasing latitude and elevation(P<0.05) and negative associations with longitude(P<0.01). Along the climatic gradients, there were U-shaped patterns in SR, and H' and D diversity indices between trees and herbs(P<0.05). SR, and H' and D diversity indices for overstory tree species were positively associated with those for understory herbs(P<0.01). These findings indicate that overstory trees and understory herbs should be protected concurrently in the TWFF to increase effectiveness of species diversity conservation programs.

关键词： diversity indices overstory trees understory herbs paleoclimate current climate elevation

Distribution and storage of soil organic and inorganic carbon under different ecological zones in Xinjiang,China

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 116-125页

作者： An Yan Baoguo Li Feng Huang Wentai Zhang Ping'an Jiang jiandong sheng Xinjiang Key Laboratory of Soil and Plant Ecological Processes College of Grassland and Environmental SciencesXinjiang Agricultural UniversityUrumqi 830052China College of Land Science and Technology China Agricultural UniversityBeijing 100193China College of Resource and Environment China Agricultural UniversityBeijing 100193China

The objective of this study was to quantify both soil organic carbon(SOC)and soil inorganic carbon(SIC)stocks in different ecological zones in Xinjiang Region,the largest arid and semi-arid region in northwest *** specific focus was on the vertical distributions of 641 typical soil profiles(0-100 cm).The study region covered five ecological zones:I-Altai/west Junggar;II-Junggar basin;III-Tianshan mountain;IV-Tarim basin;and V-Kunlun-Altun *** zones are categorized by their specific geographical locations from north to south with terrains derived from mountains to *** data used in the study were obtained from the first(1960s)and the second(1980s)National Soil Surveys and partially from the field survey of this study conducted in *** results suggest that there are 11.74 Pg SOC and 26.71 Pg SIC total stocks in the 0-100 cm surface soil over the entire study *** distributions of SOC and SIC were found to be *** Tianshan mountain zone has the highest SOC stock,followed by the Tarim basin,Kunlun-Altun mountains,Altai and west Junggar(Altai/west Junggar),and Junggar basin *** contrast,the Tarim basin zone had the highest SIC stock,followed by the Tianshan mountain,Kunlun-Altun mountains,Junggar basin,and Altai/west Junggar *** SOC content decreases gradually from northwest to southeast and from mountains to deserts;while the SIC content decreases gradually from south to *** SOC and SIC contents also change with soil *** a given ecological zone,the SOC content increased with increasing soil depth,peaked at about 20-40 cm,then it decreased with the bigger depths below 40 *** SIC contents increased gradually from 0 to 40 cm,and then decreased gradually with increasing soil depth over the 40-100 cm depth in all ecological zones except for the Tianshan mountain area.

关键词： ecological zones soil organic carbon soil inorganic carbon carbon storage vertical distribution

Characteristics of water erosion and conservation practice in arid regions of Central Asia:Xinjiang,China as an example

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International Soil and Water Conservation Research 2015年第2期3卷 97-111页

作者： Wentai Zhang Jianqin Zhou Guanglong Feng David C.Weindorf Guiqing Hu jiandong sheng Xinjiang Key Laboratory of Soil and Plant Ecological Processes College of Grassland and Environmental SciencesXinjiang Agricultural UniversityUrumqi 830052China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Department of Plant and Soil Sciences College of Agricultural Sciences and Natural ResourcesTexas Tech UniversityLubbockTX 79409USA

Located in the inland arid area of Central Asia and northwest China,Xinjiang has recently received heightened concerns over soil water erosion,which is highly related with the sustainable utilization of barren soil and limited water *** from the national soil erosion survey of China(1985-2011)and Xinjiang statistical yearbook(2000-2010)was used to analyze the trend,intensity,and serious soil water erosion *** showed that the water erosion area in Xinjiang was 87.6103 km^(2) in 2011,mainly distributed in the Ili river valley and the northern and southern Tian *** erosion gradient was generally slight and the average erosion modulus was 2184 t/(km^(2) a).During the last 26 years,the water erosion area in Xinjiang decreased by 23.2%,whereas the intensity was still *** driving factors from large to small impact included:population boom and human activities4vegetation degradation4rainfall and climate change4topography and soil erodibility4tectonics *** water erosion resulted in eco-environmental and socioeconomic losses,such as destroying farmland and grassland,triggering floods,sedimentation of reservoirs,damaging transportation and irrigation facilities,and aggravating poverty.A landscape ecological design approach is suggested for integrated control of soil ***,an average of 2.07×10^(3) km^(2) of formerly eroded area is conserved each *** study highlighted the importance and longevity of soil and water conservation efforts in Xinjiang,and offered some suggestions on ecological restoration and combating desertification in arid regions of Central Asia.&2015 International Research and Training Center on Erosion and Sedimentation and China Water and Power *** and Hosting by Elsevier *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Xinjiang Soil water erosion Soil and water conservation Ecological restoration Arid region