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Spatial-temporal variability of throughfall in a subtropical deciduous forest from the hilly regions of eastern china

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Journal of Mountain Science 2019年第8期16卷 1788-1801页

作者： ZHANG Hai-xia WU Hua-wu LI Jing HE Bin liu Jiu-fu WANG Niu DUAN wei-li LIAO Ai-min Key Laboratory of Watershed Geographic sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of chinese academy of sciences Beijing 100049China Chuzhou Hydrology Laboratory Nanjing Hydraulic Research InstitutesNanjing 210029China Tourism School Jiujiang CollegeJiujiang 332005China State Key Laboratory of Desert and Oasis ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

Throughfall variability plays a crucial role in regulating hydrological and biogeochemical processes in forest ecosystems. However, throughfall variability and its potential influencing factors remain unclear in the subtropical deciduous forest because of its complex canopy and meteorological conditions. Here, the spatial variability and temporal stability of throughfall were investigated from October 2016 to December 2017 within a deciduous forest in the subtropical hilly regions of eastern china, and the effects of meteorological variables and distance from nearest tree trunk on throughfall variability were systematically evaluated. Throughfall variability during the leafed period was slightly higher than that during the leafless period inferred from the coefficient of variation of throughfall amounts(CVTF), with 13.2%-40.9% and 18.7%-31.9%, respectively. The multiple regression model analysis suggested that the controlling factors of throughfall variability were different in studied periods: Maximum 10-min rainfall intensity, wind speed and air temperature were the dominant influencing factors on throughfall variability during the leafed period, with the relative contribution ratio(RCR) of 25.9%, 18.7% and 8.9%, respectively. By contrast, throughfall variability was affected mainly by the mean rainfall intensity(RCR=40.8%) during the leafless period. The temporal stability plots and geostatistical analysis indicated that spatial patterns of throughfall were stable and similar among rainfall events. Our findings highlight the important role of various meteorological factors in throughfall variability and are expected to contribute to the accurate assessment of throughfall, soil water and runoff within the subtropical forests.

关键词： Throughfall variability Spatial heterogeneity Temporal stability Meteorological variables Canopy structure Subtropical forest

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Human activity during the late Pleistocene in the Lop Nur region, northwest china： Evidence from a buried stone artifact

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Science china Earth sciences 2018年第11期61卷 1659-1668页

作者： Kangkang LI Xiaoguang QIN Xiaoyan YANG Bing XU Lei ZHANG Guijin MU Dong wei Chunxue WANG Yong WU Xiaohong TIAN Yongchong LIN Wen LI Jiaqi liu Yinxin JIAO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044 China University of chinese academy of sciences Beijing 100049 China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100101 China xinjiang institute of ecology and geography Chinese Academy of Sciences Urumqi 830011 China School of Archaeology Jilin University Changchun 130012 China xinjiang institute of Archaeology Urumqi 830011 China Bureau of Cultural Heritage of Ruoqiang County Ruoqiang 841800 China

The Lop Nur region, in the east part of Tarim Basin, was an important transportation junction between west and east,north and south Eurasia. However, previous studies on prehistoric human activity have concentrated mostly on the Bronze Age,whereas that during the Stone Age remains largely unresearched. Here, we present a new direct evidence of human activity in the late Pleistocene, recorded on a grinding stone buried in a lacustrine sediment section of the Lop Nur region. The grain size distribution of the sediment section indicates that the site was probably in the center of a lake with weak hydrodynamic environment. Therefore, the stone artifact can only be carried to here by people instead of river and it was never move as soon as left here. Results of radiocarbon dating, the evident stratigraphic relations between the stone artifact and the sedimentary formation, indicate that the human activity could extend to approximately 13 ka BP. Furthermore, the results of starch-grain and use-wear analyses suggest that ancient humans gathered seeds of Triticeae, roots, and tubers and used the grinding stone to simply process selected plant as plant foodstuffs during this period. It implies that the environmental conditions in the river delta of the Lop Nur were inhabitable during the late Pleistocene.

关键词：人工制品 Lop 更新世石头证据动力学环境中国西北

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Does nitrogen application rate affect the moisture content of corn grains?

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Journal of Integrative Agriculture 2021年第10期20卷 2627-2638页

作者： ZHANG Yuan-meng XUE Jun ZHAI Juan Zhang Guo-qiang ZHANG Wan-xu WANG Ke-ru MING Bo HOU Peng XIE Rui-zhi liu Chao-wei LI Shao-kun Key Laboratory of Oasis Eco-Agriculture Xinjiang Production and Construction Corps/Agricultural CollegeShihezi UniversityShihezi 832000P.R.China institute of Crop sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and EcologyMinistry of Agriculture and Rural AffairsBeijing 100081P.R.China

Nitrogen fertilizer application is an important measure to obtain high and stable corn yield,and the moisture content of corn grains is an important factor affecting the quality of mechanical grain *** this study,four different nitrogen fertilizer treatments from 0 to 450 kg ha^(–1) pure nitrogen were set for a planting density of 12.0×10^(4) plants ha^(–1) in 2017 and 2018,and 18 different nitrogen fertilizer treatments from 0 to 765 kg ha^(–1) pure nitrogen were set for planting densities of 7.5×10^(4) and 12.0×10^(4) plants ha^(–1) in 2019,to investigate the effect of nitrogen application rate on the moisture content of corn *** each treatment,the growth of corn,leaf area index(LAI)of green leaves,grain moisture content,and grain dehydration rate were *** results showed that,as nitrogen application increased from 0 to 765 kg ha^(–1),the silking stage was delayed by about 1 day,the maturity stage was delayed by about 1–2 days,and the number of physiologically mature green leaves and LAI *** and after physiological maturity,the extreme difference in grain moisture content between different nitrogen application rates was 1.9–4.0%.As the amount of nitrogen application increased,the corn grain dehydration rate after physiological maturity decreased,but it did not reach statistical significance between nitrogen application rate and grain dehydration *** significant correlation was observed between LAI at physiological maturity and grain dehydration rate after physiological *** short,nitrogen application affected the grain moisture content of corn at and after physiological maturity,however,the difference in grain moisture content among different nitrogen application rates was *** results suggest that the effect of nitrogen application on the moisture content of corn grains should not be considered in agricultural production.

关键词： nitrogen corn grain moisture content leaf area index physiological maturity

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新疆巩乃斯河流域季节性积雪中硫酸盐的时空分布与来源

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干旱区地理 1998年第2期21卷 29-35页

作者：姜逢清魏文寿刘明哲李卫红汪新军中国科学院新疆地理研究所乌鲁木齐830011

1996～1997年冬季，一次针对巩乃斯河流域季节性积雪化学成分的调查与研究工作得以开展，其间共采集了约100个新、老雪样。经室内分析发现巩乃斯河流域季节性积雪中含有相对丰富的硫酸盐。本文主要分析了该流域季节性积雪的SO4^(2-)离... 详细信息

1996～1997年冬季，一次针对巩乃斯河流域季节性积雪化学成分的调查与研究工作得以开展，其间共采集了约100个新、老雪样。经室内分析发现巩乃斯河流域季节性积雪中含有相对丰富的硫酸盐。本文主要分析了该流域季节性积雪的SO4^(2-)离子以及与之有关的K^+＋Na^+和Ca^(2+)离子的时间与海拔分布特征，并重点讨论了硫酸盐类物质的来源。

关键词：巩乃斯河流域季节性积雪硫酸盐时空分布

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多因素权衡下的国家公园功能分区一一以青海湖国家公园为例

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Journal of Geographical sciences 2022年第10期32卷 1969-1997页

作者：赵力杜鸣溪张炜李从娟刘秋雨康翔周典 School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Northwest Surveying Planning Institute of National Forestry and Grassland AdministrationKey Laboratory National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid RegionsXi’an 710048China School of Public Policy and Administration Xi'an Jiaotong UniversityXi’an 710049China School of Horticulture and Forestry Central China Agricultural UniversityWuhan 430070China xinjiang institute of ecology and geography CASUrumqi 830011China Department of Biological sciences University of Quebec at MontrealMontreal H3C 3P8Canada

Functional zoning is an important mechanism for achieving national park planning and management *** functional zoning is of great significance to the protection of ecosystem legitimacy and integrity,the appropriate utilization of resources,community integration,and feasible *** the present study,the proposed Qinghai Lake National Park is the research *** on the critical goal of ecological protection,the importance of ecosystem service functions and the ecological sensitivities were *** results showed that the ecosystem service functions and the ecological sensitivity of the whole region are *** them,lake,river and wetland as the most strictly protected ecosystems account for the highest *** this study divided the proposed Qinghai Lake National Park into five functional areas through grid calculations,spatial analysis and multifactor *** results indicated that the goal of functional zoning for national park is to maximize the overall utility of park protection value and its comprehensive functions based on its spatial units with different functions,management and control *** zoning scheme addresses the lack of sustainable development in Qinghai Lake National Park due to ecological environmental changes and single-resource zoning with resource protection as the primary *** study can serve as a reference for spatial functional zoning methods of national land parks,nature reserves and other natural protected areas.

关键词： national park functional zoning interference from human activities multifactor trade-off

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干旱区耕地安全压力测试及时空演变特征研究——以新疆为例

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资源开发与市场 2022年第7期38卷 792-800页

作者：孙德华刘维忠盛洋新疆农业大学经济管理学院新疆乌鲁木齐830052 新疆农业大学干旱区农村发展研究中心新疆乌鲁木齐830052 中国科学院新疆生态与地理研究所新疆乌鲁木齐830011

以典型干旱区新疆为研究区域,基于对耕地资源和耕地生态安全压力特征的理论及现状分析,分别运用耕地拉力指数模型、压力—状态—响应模型构建指标体系、AHP—熵值法确定权重,测算得到2010—2019年新疆耕地资源(数量)压力状况和耕地生态... 详细信息

以典型干旱区新疆为研究区域,基于对耕地资源和耕地生态安全压力特征的理论及现状分析,分别运用耕地拉力指数模型、压力—状态—响应模型构建指标体系、AHP—熵值法确定权重,测算得到2010—2019年新疆耕地资源(数量)压力状况和耕地生态安全值,并进一步对各地州的耕地生态安全进行测度,探究其时空演变特征。结果表明:2010—2019年新疆耕地资源(数量)处于“安全压力区”,而耕地生态处于“不安全”状态,给新疆整体的耕地安全带来了较大压力;2010—2019年各地州的耕地生态安全状况差距较大,安全指数呈“北疆>南疆>东疆”的空间格局。根据压力来源,提出对策建议。

关键词：压力测试耕地拉力指数模型压力—状态—响应模型 AHP—熵值法耕地生态安全

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紫皮大蒜营养成分与活性成分的分析比较

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食品研究与开发 2022年第20期43卷 102-109页

作者：王煜伟尹卫李琳琳王乐王永红刘晓军洒威梁健青海大学省部共建三江源生态与高原农牧业国家重点实验室青海西宁810016 浙江清华长三角研究院浙江嘉兴314006

采用多种分析方法对青海乐都、海南海口、贵州毕节、重庆梁平、江西赣州、江苏邳州、安徽阜阳、陕西渭南、云南曲靖、辽宁铁岭、河北保定、黑龙江哈尔滨、新疆塔城、四川成都、甘肃民乐、内蒙古阿拉善左旗、河南杞县、新疆乌鲁木齐和青... 详细信息

采用多种分析方法对青海乐都、海南海口、贵州毕节、重庆梁平、江西赣州、江苏邳州、安徽阜阳、陕西渭南、云南曲靖、辽宁铁岭、河北保定、黑龙江哈尔滨、新疆塔城、四川成都、甘肃民乐、内蒙古阿拉善左旗、河南杞县、新疆乌鲁木齐和青海格尔木大格勒共计19个不同产地紫皮大蒜的常规营养成分、氨基酸、脂肪酸、矿质元素及总多酚、总黄酮等活性成分进行比较分析。结果表明:青海乐都和甘肃民乐的紫皮大蒜粗脂肪、粗蛋白和总糖含量均高于其他17个产地所产大蒜。此外,青海乐都紫皮大蒜的氨基酸、脂肪酸、总多酚和总黄酮含量与其他大蒜相比也存在一定的差异。其中青海乐都、青海格尔木大格勒、甘肃民乐、辽宁铁岭和黑龙江哈尔滨紫皮大蒜中18种氨基酸、6种脂肪酸、总多酚与总黄酮的含量明显高于其他14种紫皮大蒜。这可能与西北地区独特的冷凉气候有关。在矿质元素方面,青海乐都紫皮大蒜硒含量为(58.81±0.62)μg/kg,锗含量为(22.18±0.23)μg/kg,远远高于其他产地的紫皮大蒜。

关键词：紫皮大蒜营养物质矿质元素总多酚总黄酮

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Global methane and nitrous oxide emissions from terrestrial ecosystems due to multiple environmental changes

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Ecosystem Health and Sustainability 2015年第1期1卷 23-43页

作者： Hanqin Tian Guangsheng Chen Chaoqun Lu Xiaofeng Xu wei Ren Bowen Zhang Kamaljit Banger Bo Tao Shufen Pan Mingliang liu Chi Zhang Lori Bruhwiler Steven Wofsy International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnAlabama 36849 USA Environmental sciences Division Oak Ridge National LaboratoryOak RidgeTennessee 37831 USA Department of Biological sciences University of Texas at El Paso500 West University AvenueEl PasoTexas 79902 USA Department of Civil and Environmental Engineering Washington State UniversityPullmanWashington 99164 USA xinjiang institute of ecology and geography Chinese Academy of SciencesUrumqi 830011 China NOAA Earth System Research Laboratory 325 BroadwayBoulderColorado 80305-3337 USA Department of Earth and Planetary Science Harvard University29 Oxford StreetCambridgeMassachusetts 02138 USA

Greenhouse gas(GHG)-induced climate change is among the most pressing sustainability challenges facing humanity today,posing serious risks for ecosystem ***(CH_(4))and nitrous oxide(N_(2)O)are the two most important GHGs after carbon dioxide(CO_(2)),but their regional and global budgets are not well *** this study,we applied a process-based coupled biogeochemical model to concurrently estimate the magnitude and spatial and temporal patterns of CH_(4)and N_(2)O fluxes as driven by multiple environmental changes,including climate variability,rising atmospheric CO_(2),increasing nitrogen deposition,tropospheric ozone pollution,land use change,and nitrogen fertilizer *** estimated CH_(4)and N_(2)O emissions from global land ecosystems during 1981-2010 were 144.39±12.90 Tg C/yr(mean 62 SE;1 Tg=1012 g)and 12.52±0.74 Tg N/yr,*** simulations indicated a significant(P,0.01)annually increasing trend for CH_(4)(0.43±0.06 Tg C/yr)and N_(2)O(0.14±0.02 Tg N/yr)in the study ***_(4)and N_(2)O emissions increased significantly in most climatic zones and continents,especially in the tropical regions and *** most rapid increase in CH_(4)emission was found in natural wetlands and rice fields due to increased rice cultivation area and climate warming.N_(2)O emission increased substantially in all the biome types and the largest increase occurred in upland crops due to increasing air temperature and nitrogen fertilizer ***,the three major GHGs(CH_(4),N_(2)O,and CO_(2))should be simultaneously considered when evaluating if a policy is effective to mitigate climate change.

关键词： coupled biogeochemical cycles global warming potential greenhouse gas methane nitrous oxide terrestrial ecosystem

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新疆西北部萨吾尔山西伯利亚落叶松树轮宽度的气候响应特征

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沙漠与绿洲气象 2023年第5期17卷 10-18页

作者：尚华明范子昂张瑞波张同文张合理喻树龙秦莉魏文寿中国气象局乌鲁木齐沙漠气象研究所/新疆树木年轮生态实验室/中国气象局树木年轮理化研究重点开放实验室新疆乌鲁木齐830002 新疆维吾尔自治区防雷减灾中心新疆乌鲁木齐830002

树木生长对气候变化的响应研究不仅能为全球变化背景下森林生态系统的响应提供关键参数,也是树轮气候学研究的基础。利用新疆西北部萨吾尔山南坡的西伯利亚落叶松树木年轮宽度资料,建立了不同海拔高度的4个树轮宽度年表,采用相关分析和... 详细信息

树木生长对气候变化的响应研究不仅能为全球变化背景下森林生态系统的响应提供关键参数,也是树轮气候学研究的基础。利用新疆西北部萨吾尔山南坡的西伯利亚落叶松树木年轮宽度资料,建立了不同海拔高度的4个树轮宽度年表,采用相关分析和冗余分析法分析了树轮年表特征及其对气候的响应特征。结果表明:(1)不同海拔西伯利亚落叶松树轮宽度年表均具有较高的敏感度和一致性,可能包含丰富的气候信息。树轮年表参数有较一致的规律性:平均敏感度、标准差和信噪比随海拔高度降低逐渐增大;反映树轮对环境要素响应滞后效应的一阶自相关系数随海拔高度降低而减小。(2)随着海拔高度的降低,树轮宽度年表与生长季5—9月气温的正相关逐渐减弱,直至变为负相关;与反映水分状况的气象要素(降水量、相对湿度和水汽压)由不显著相关变为显著正相关(P<0.01)。萨吾尔山南坡海拔2 000~2 100 m是西伯利亚落叶松树轮宽度对气候响应关系发生转折的关键高度。(3)位于下树线区域西伯利亚落叶松树轮宽度受年降水量(上年7月—当年6月)和当年生长季(5—9月)气温共同影响,具备开展区域干旱指数重建的潜力。

关键词：新疆萨吾尔山树木年轮西伯利亚落叶松气候响应

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基于LightGBM和多光谱—SAR多特征综合的中亚干旱区城市不透水面提取

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遥感技术与应用 2023年第2期38卷 319-331页

作者：刘希鸣阿里木·赛买提王伟吉力力·阿不都外力中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室新疆乌鲁木齐830011 中国科学院大学北京100049 中国科学院中亚生态与环境研究中心新疆乌鲁木齐830011

不透水面是评价城市化水平和城市生态环境的重要指标,是近年来城市遥感研究中的热点方向之一。与湿润、半湿润区相比,干旱区城市植被覆盖度较低,不透水面与裸土、荒漠之间相似的光谱特征导致传统基于光学影像的亚像元分解法与光谱指数... 详细信息

不透水面是评价城市化水平和城市生态环境的重要指标,是近年来城市遥感研究中的热点方向之一。与湿润、半湿润区相比,干旱区城市植被覆盖度较低,不透水面与裸土、荒漠之间相似的光谱特征导致传统基于光学影像的亚像元分解法与光谱指数法在干旱区不透水面提取的适用性降低。针对该问题,提出一种多光谱与合成孔径雷达(SAR)影像多特征综合的方法以增大不透水面与其他地物覆盖类型之间的特征差异,从而提取干旱区城市不透水面。以阿斯塔纳、塔什干和杜尚别3个中亚城市为研究区,哨兵2号和哨兵1号影像为数据源,通过LightGBM算法对多光谱和SAR图像的空间特征、SAR的极化特征进行分类并提取不透水面。研究对比了不同特征组合以及不同分类方法的不透水面提取结果,实验结果表明:多光谱与SAR影像多特征综合的方法能有效提高干旱区不透水面提取精度,明显改善干旱区其他土地覆盖类型错分为不透水面的问题;LightGBM算法与XGBoost、HistGBT等基于梯度提升决策树的算法和随机森林等方法相比能获取更高的精度,更适用于干旱区不透水面提取。这表明基于LightGBM以及多光谱和SAR多特征联合的方法能够有效提取中亚干旱区城市不透水面。

关键词：不透水面部分重建的形态学属性剖面 LightGBM 干旱区中亚

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建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

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