检索结果-南通市图书馆

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

Science china Earth sciences 2005年第12期48卷 2203-2213页

作者： cao hongying1, liang tao1 & tao shu2.1. institute of geographical sciences and natural resources research, Chinese Academy of {2., beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china institute of geographical {2. and natural resources research Chinese Academy of Sciences Beijing China Laboratory for Earth Surface Processes Peking University Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952.2.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952.1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.3t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spatial patterns of terrestrial net ecosystem productivity in china during 1981―2.00

引用

Science china Earth sciences 2007年第5期50卷 745-753页

作者： tao Bo1, cao MingKui1, LI KeRang1, GU FengXue1, JI JinJun1,2. HUANG Mei1 & ZHANG LeiMing1 1 {2. of geographical {2. and natural resources research, Chinese Academy of {2., beijing 100101, china 2.{2. of Atmospheric Physics, Chinese Academy of {2., beijing 100101, china institute of geographical {2. and natural resources research Chinese Academy of Sciences Beijing 100101 China institute of geographical {2. and natural resources research Chinese Academy of Sciences Beijing 100101 China institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100101 China

As the third largest country in the world, china has highly variable environmental condition and eco- logical pattern in both space and time. Quantification of the spatial-temporal pattern and dynamic of terrestrial ecosystem carbon cycle in china is of great significance to regional and global carbon budget. In this study, we used a high-resolution climate database and an improved ecosystem process-based model to quantify spatio-temporal pattern and dynamic of net ecosystem productivity (NEP) in china and its responses to climate change during 1981 to 2.00. The results showed that NEP increased from north to south and from northeast to southwest. Positive NEP (carbon sinks) occurred in the west of Southwest china, southeastern Tibet, Sanjiang Plain, Da Hinggan Mountains and the mid-west of North china. Negative NEP (carbon sources) were mainly found in Central china, the south of Southwest china, the north of Xinjiang, west and north of Inner Mongolia, and parts of North china. From the 1980s to 1990s, the increasing trend of NEP occurred in the middle of Northeast china Plain and the Loess Plateau and decreasing trends mainly occurred in a greater part of Central china. In the study period, natural forests had minimal carbon uptake, while grassland and shrublands accounted for nearly three fourths of the total carbon terrestrial uptakes in china during 1981―2.00.

关键词： china terrestrial ecosystem carbon cycle spatial patterns climate change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Estimation of ammonia nitrogen load from nonpoint sources in the Xitiao River catchment, china

引用

Journal of Environmental sciences 2008年第10期20卷 1195-1201页

作者： liang tao WANG Shanna {2. hongying ZHANG Chaosheng LI Haitao LI Hengpeng SONG Wenchong CHONG Zhongyi institute of Geographic sciences and {2. resources research Chinese Academy of Sciences Beijing 100101 China Department of Geography National University of Ireland Galway Ireland Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

Ammonia nitrogen (NH4+-N) is one of the three main forms of total nitrogen (TN). Most studies have estimated the load of TN from nonpoint sources instead of one specific form. The relationship between land use and concentrations of NH4+-N in runoff was analyzed using the hydraulic analysis functions of a Geographic Information Systems (GIS), and the annual loads of NH4+-N in the Xitiao River catchment were estimated according to model results. The results suggested that the calculated annual loads of NH4+-N...

关键词： nonpoint source pollution NH4+-N Geographic Information systems (GIS) output rate load

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Three-dimensional delineation of soil pollutants at contaminated sites: Progress and prospects

引用

Journal of geographical sciences 2022年第8期32卷 1615-1634页

作者： tao Huan LIAO Xiaoyong cao {2. ZHAO Dan HOU Yixuan institute of Geographic sciences and {2. resources research CASBeijing 100101China Chinese Academy of Environmental Planning Beijing 100012China University of Chinese Academy of sciences Beijing 100049China

The precision remediation and redevelopment of contaminated sites are crucial issues for improving the human settlement and constructing a beautiful china. Three-dimensional delineation of soil pollutants at contaminated sites is a prerequisite for precision remediation and redevelopment. However, a contaminated site is a three-dimensional complex system coupling multiple spatial elements above-and under-ground. The complexity incurs high uncertainties about the three-dimensional delineation of soil pollutants based on sparse borehole and spatial statistics and inference models. This paper first systematically reviewed the objectives of fine three-dimensional delineation of soil pollutants, the sampling strategies for soil boring, the commonly used models for delineating soil pollutants, and the relevant cases of applying these models at contaminated sites. We then summarized the effects of borehole data and three-dimensional models on soil pollutants' delineation results from biased characteristics and nonstationary conditions. The present research status and related issues on correcting the biased characteristics and nonstationary conditions were analyzed. Finally, based on the problems and challenges, we suggested the three-dimensional delineation of soil pollutants in the underground “black box” for future research from the following six priority areas: multi-scenarios, nonstationary, non-linearity, multi-source data fusion, multiple model coupling, and the delineation of co-contaminated sites.

关键词： contaminated sites soil pollution three-dimensional delineation model sparse and biased nonstationarity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于作物模型与机器学习的水稻障碍型冷害脆弱性研究

引用

中国农业气象 2024年第9期45卷 1053-1066页

作者：张静张朝张亮亮曹娟骆玉川韩继冲陶福禄北京师范大学教育部巨灾模拟与系统性风险应对国际合作联合实验室珠海519087 北京师范大学国家安全与应急管理学院北京100875 广东省科学院广州地理研究所广州510070 中国科学院地理科学与资源研究所陆地表层格局与模拟重点实验室北京100101

以水稻障碍型冷害为例,提出一种突破数据限制并兼顾承灾体反应机理的新方法,构建农业气象灾害脆弱性曲线。基于1990-2.10年气象数据设计水稻抽穗开花期的障碍型冷害情景,通过MCWLA-Rice作物模型和机器学习混合建模法计算对应的水稻单产... 详细信息

以水稻障碍型冷害为例,提出一种突破数据限制并兼顾承灾体反应机理的新方法,构建农业气象灾害脆弱性曲线。基于1990-2.10年气象数据设计水稻抽穗开花期的障碍型冷害情景,通过MCWLA-Rice作物模型和机器学习混合建模法计算对应的水稻单产损失,最终建立不同水稻主产区的障碍型冷害脆弱性曲线,并对1961-2.10年水稻障碍型冷害单产损失快速评估。结果表明:(1)机器学习可有效重现作物模型模拟精度(RRMSE2.>0.93)。(2.水稻障碍型冷害脆弱性具有明显的空间和种植制度差异,高纬地区到低纬地区水稻脆弱性整体呈下降趋势,且晚稻脆弱性普遍低于早稻。(3)一季稻抽穗开花期障碍型冷害的年均单产损失(12.4kg·hm^(−2.)高于双季稻(早稻:868kg·hm^(−2.;晚稻:807kg·hm^(−2.)。

关键词：水稻低温冷害脆弱性作物模型机器学习

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Damage evaluation of soybean chilling injury based on Google Earth Engine(GEE)and crop modelling

引用

Journal of geographical sciences 2020年第8期30卷 1249-1265页

作者： cao Juan ZHANG Zhao ZHANG liangliang LUO Yuchuan LI Ziyue tao Fulu State Key Laboratory of Earth Surface Processes and Resource Ecology/MEM&MoE Key Laboratory of Environmental Change and natural Hazards Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of resources and Environment University of Chinese Academy of SciencesBeijing 100049China

Frequent chilling injury has serious impacts on national food security and in northeastern china heavily affects grain *** and accurate measures are desirable for assessing associated large-scale impacts and are prerequisites to disaster ***,we propose a novel means to efficiently assess the impacts of chilling injury on *** chilling injury events were diagnosed in 1989,1995,2.03,2.09,and 2.18 in Oroqen *** total,512.combinations scenarios were established using the localized CROPGRO-Soybean ***,we determined the maximum wide dynamic vegetation index(WDRVI)and corresponding date of critical windows of the early and late growing seasons using the GEE(Google Earth Engine)platform,then constructed 1600 cold vulnerability models on CDD(Cold Degree Days),the simulated LAI(Leaf Area Index)and yields from the CROPGRO-Soybean ***,we calculated pixel yields losses according to the corresponding vulnerability *** findings show that simulated historical yield losses in 1989,1995,2.03 and 2.09 were measured at 9.6%,2..8%,50.5%,and 15.7%,respectively,closely(all errors are within one standard deviation)reflecting actual losses(6.4%,39.2.,47.7%,and 13.2.,respectively).The above proposed method was applied to evaluate the yield loss for 2.18 at the pixel ***,a sentinel-2. image was used for 10-m high precision yield mapping,and the estimated losses were found to characterize the actual yield losses from 2.18 cold *** results highlight that the proposed method can efficiently and accurately assess the effects of chilling injury on soybean crops.

关键词： chilling injury Google Earth Engine(GEE) CROPGRO-Soybean soybean yield loss cold degree days(CDD)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

场地土壤污染物含量三维刻画的研究进展

引用

地理学报 2022年第3期77卷 559-573页

作者：陶欢廖晓勇曹红英赵丹侯艺璇中国科学院地理科学与资源研究所北京100101 中国科学院大学北京100049 生态环境部环境规划院北京100012

污染场地精准修复与再开发利用是改善人居环境、建设美丽中国所面临的重要课题。场地土壤污染物含量三维刻画是精准修复与再开发利用的基础。然而,场地环境是一个耦合地上地下多要素的复杂三维系统,使得基于离散稀疏土壤钻井样点和空间... 详细信息

污染场地精准修复与再开发利用是改善人居环境、建设美丽中国所面临的重要课题。场地土壤污染物含量三维刻画是精准修复与再开发利用的基础。然而,场地环境是一个耦合地上地下多要素的复杂三维系统,使得基于离散稀疏土壤钻井样点和空间统计推断模型的场地土壤污染物含量刻画结果存在着较大的不确定性。本文梳理了场地土壤污染物含量三维精细刻画的目的和钻井布设方式、常用的三维刻画模型和相关案例,分析了土壤钻井数据的“稀疏偏性”特征对刻画结果的影响,总结了“非平稳浓度场”条件下三维土壤污染物含量插值模型的研究现状和存在问题。在此基础上,从多情景、非平稳、非线性、多源数据融合、多类模型耦合和复合污染刻画6个方面,展望了场地地下“黑箱”环境土壤污染物含量精细刻画的研究趋势。

关键词：污染场地土壤污染三维刻画模型稀疏偏性非平稳

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

陆表自然和人文要素相互作用——“全球变化及应对”重点专项研究进展

引用

大气科学学报 2024年第1期47卷 1-22页

作者：王开存王灿李龙辉汪涛吴国灿付永硕马倩张井勇蔡闻佳曹静喻朝庆朱华晟南卓铜陈旻张晶纪多颖沈妙根唐文君何斌占文凤北京大学城市与环境学院北京100871 清华大学环境学院北京100084 南京师范大学地理科学学院江苏南京210023 中国科学院青藏高原研究所北京100085 北京师范大学地理科学学部北京100875 北京师范大学水科学研究院北京100875 中国科学院大气物理研究所北京100029 清华大学地球系统科学系北京100084 清华大学经济与管理学院北京100084 海南大学生态与环境学院海南海口570228 南京大学国际地球系统科学研究所江苏南京210023

在国家重点研发计划支持下,项目提出了陆表不均一性检测和订正的新方法,解决了渐变型不均一性检测和订正的难题,构建了中国地表太阳辐射、气温、地温、风速和降水等参数均一化站点和格点数据集,修订了关于中国地表风速变化趋势、增温格... 详细信息

在国家重点研发计划支持下,项目提出了陆表不均一性检测和订正的新方法,解决了渐变型不均一性检测和订正的难题,构建了中国地表太阳辐射、气温、地温、风速和降水等参数均一化站点和格点数据集,修订了关于中国地表风速变化趋势、增温格局及其形成机制的结论。融合多源数据,构建并验证了千米级、流域级或县域级的电厂、人口、生物质能、取水量、氮排放、二氧化碳排放等影响自然系统的关键人文要素历史和未来预估数据集。构建了未来关键人文要素情景,研制了碳中和目标下甲烷和氧化亚氮排放情景和用于驱动全球模式的未来情景,预估了中国碳中和战略的实施对全球变暖的减缓作用,发现中国碳中和对远期和中期全球变暖的减缓作用显著。给出了中国各省份水体氮排放安全阈值及超越时间,阐明了中国粮食产量与氮施肥的关系,提出了在保障粮食安全的前提下减少水体氮排放的有效途径,指出重构城乡养分循环体系是同时保障粮食安全和恢复水质的必要途径。发现全球饱和水汽压差的年际变化与大气二氧化碳浓度上升速率的年际变化显著相关,阐明了饱和水汽压差变化在调控生态系统生产力中的重要角色以及多因素耦合作用在生态系统生产力变化中的复杂影响。建议更全面细致地评估中国各种碳中和实现路径的社会经济和自然生态影响,以保证碳中和目标与其他可持续发展目标的协同实现。

关键词：气候变化未来情景碳中和陆面过程生态系统生产力粮食安全

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Global Carbon Project (GCP) beijing Office:a new bridge for understanding regional carbon cycles

引用

Journal of geographical sciences 2006年第3期16卷 375-377页

作者： tao Bo cao Mingkui YU Guirui LIU Jiyuan WANG Shaoqiang YAN Huimin institute of Geographic sciences and {2. resources research CAS Beijing 100101 China

It has been widely accepted that human activities, especially burning fossil fuels and land use change, have altered the climate on earth and anthropogenic carbon fluxes have become comparable in magnitude with the natural fluxes in the global carbon cycle. The present and potential threat of adverse consequences has focused the attention of the scientists, policy makers and general public on the interaction among carbon cycle, climate change and human system. Asia is a hot spot from environmental change and sustainable development perspectives. The development pathways and environmental changes in the region have obvious consequences for the regional carbon cycle, even for global carbon budget, and the complex, diverse social, economic and environmental conditions make it highly diffficult to understand and quantify these consequences. The GCP beijing Office ＂will have a supporting and coordinating role and will provide coordination, leadership and capacity building on carbon cycle {2. in china and to the larger region of Asia＂ and ＂liaise with the two International Project Offices based in Canberra and Tsukuba to coordinate a regional and global strategy consistent with the GCP Science and Implementation Framework＂.

关键词： GCP regional office carbon cycle china

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

GEE环境下的玉米低温冷害损失快速评估

引用

遥感学报 2020年第10期24卷 1206-1220页

作者：张亮亮张朝曹娟李子悦陶福禄北京师范大学地理科学学部环境演变与自然灾害教育部重点实验北京100875 中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101

大范围、及时、准确的灾害损失评估与制图对防灾减灾、农业保险和粮食安全等至关重要。针对传统灾害损失评估方法空间尺度单一、泛化能力差、时效性低,可操作性弱等问题,本文建立了一种遥感产品耦合作物模型的多尺度的灾害损失评估方法M... 详细信息

大范围、及时、准确的灾害损失评估与制图对防灾减灾、农业保险和粮食安全等至关重要。针对传统灾害损失评估方法空间尺度单一、泛化能力差、时效性低,可操作性弱等问题,本文建立了一种遥感产品耦合作物模型的多尺度的灾害损失评估方法MDLA(a Multiscale Disaster Loss Assessment)。该方法利用作物模型的多情景模拟产生大量的灾害样本,结合对应日期的遥感指标构建灾害脆弱性模型,依托Google Earth Engine(GEE)平台将其应用到高分辨率遥感影像和格点灾害指标进行逐象元评估。以鄂伦春自治旗玉米为例,基于精细校准的CERES-Maize模型的模拟,利用两个生长季窗口的LAI和冷积温(CDD)建立统计模型来刻画低温对最终产量的影响,结合Sentinel-2.据逐格点计算完成高精度损失制图。结果显示,校准后的CERES-Maize模拟物候和产量的NRMSE分别为3.3%和8.9%。冷害情景模拟结果表明不同类型和生育期的低温冷害对玉米产量的影响不尽相同,其中生长峰值期(出苗—吐丝和吐丝—灌浆)最为敏感。回代检验显示,MDLA方法估算精度为11.4%,与历史冷害年份的实际损失相吻合。经评估,鄂伦春2.18-08-09的冷害导致玉米减产2..7%,受灾面积1.86×104ha,其中高海拔地区损失较重(减产率>2.%),低温冷害对该区玉米生产构成了严重的威胁。与现有的统计回归、作物模型模拟以及同化等技术相比,其优势在于:(1)结合遥感观测和作物模型模拟技术能更好地刻画了灾害对产量的影响过程;(2.利用GEE平台快速处理海量遥感数据,提高了灾害损失评估的时效性;(3)不受地面实测数据的限制,易操作,可实现动态、多尺度(象元、田块、村,县等)的损失评估,这为防灾减损、维持粮食丰产稳产提供了保障,也为农业保险的业务化运行提供了思路。

关键词：遥感多尺度灾害损失评估(MDLA) Google Earth Engine 作物模型冷害指标玉米

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

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

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

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

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

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

请选择保存的检索档案：

请选择收藏分类：