Subjects: Geosciences >> Geography submitted time 2023-12-06 Cooperative journals: 《干旱区地理》
Abstract：城市边缘区是城市化进程中变化最活跃的区域，科学认知边缘区的体系架构是推动城市可持续发展的重要内容，也是地理与规划学科的重要研究对象。以19912021年相关主题词文献为依据对边缘区的概念演化进行了深入阐述。在辨析关联概念本质内涵的基础上，以特征要素-研究视角-衍生概念为主线对城市边缘区体系的理论内涵进行阐释，并构建了城乡边缘区、城城边缘区、城野边缘区的分类体系。研究发现，学界对边缘区的关联概念与内涵认知基本统一。相较于其他概念，城市边缘区具有更均衡的分析视角和更好的国际统一性。通过对城乡社会经济要素流动分析，土地、人口和经济成为聚焦边缘区特征的关键要素。今后及未来的一段时期，城市边缘区需要进一步完善理论架构体系，加强数据信息的采集以构建多要素、多尺度与多维度的评价指标体系，亟待扩充中小型规模城市及长时间序列的动态化研究，以充分挖掘区域间的关联耦合，实现城市空间的合理规划布局和可持续发展。
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The archives resources of field stations of Chinese Academy of Sciences (CAS) are important basic scientific and technological resources of the country. In the new era, China has put forward new requirements for the work of scientific research archives. The open sharing and network construction of field stations pose new challenges to the archives management of field stations. In order to deal with the new problems of field station archives management, based on the investigation of the data, documents, and archives management of 137 field stations and 50 supporting affiliations of CAS, this paper analyzes the current situation and problems of field station archives management, and explores the suggestions for improvement. This paper has certain practical and guiding significance for improving the archives management level of CAS field stations, enriching the content of scientific research archives, and building a basic science and technology resource system.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The temperate forest ecosystem in China is an important part of the ecological barrier in Northeast China. It not only breeds abundant biodiversity, but also is an important timber resource cultivation base and an important support for China to cope with climate change. Due to unreasonable over-harvesting and utilization, the structure and function of temperate mixed forests have been seriously affected, which has significantly affected the regional ecological security. The Research Station of Changbai Mountain Forest Ecosystem, Chinese Academy of Sciences (Changbai Mountain Station), takes revealing the structure, function, and evolution process of the original broad-leaved Korean pine forest in temperate zone of China as the core, carries out long-term monitoring and experimental research, finds that the old forest still has the ability of sustainable carbon sink, and reveals the number of vegetation, the number of big trees, the water conductivity and anti-embolism ability of trees have important effects on forest productivity. It is clarified that the increase of CO2 concentration and N addition can increase the carbon sink and carbon sequestration ability of ecosystem through control experiments. The role of mast seeding mechanism and scale in forest community construction is discovered, it revealed that the environment filtration, diffusional limitation, and random dilution are the main mechanisms for the formation and maintenance of biodiversity in broad-leaved Korean pine forests, and the relationships between abovegroundunderground and biodiversity-productivity in the process of forest community succession are explored. The research results provide theoretical support for revealing carbon sinks of forest ecosystems and their formation and maintenance mechanisms, promoting the restoration of structures and functions of disturbed temperate forest ecosystems, and building regional ecological security. At the same time, Changbai Mountain Station has cooperated with domestic and foreign scientific research institutes, colleges and universities, developed and demonstrated the decision support system of forest ecosystem management in cooperation with the local forestry bureaus. Changbai Mountain Station has become an important research base of Forest Ecosystem Science in temperate zone of China, and also a scientific research supported platform of integrated forestry industry, education, and research, as well as cradle and incubator of ecology and forestry talent in China.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Compared with soil degradation of black soil of other areas in the world, which caused by conventional tillage regarding as ploughed with residue return, soil degradation in Northeast China caused by rotary-till and residue remove or burning is more serious. Conservation tillage with residue cover and no or reduced tillage is one of the most important techniques for the protection and utilization of black soil. This paper briefly presents the derivation and definition of conservation tillage, and its main techniques in the world, as well as the issue of application and extension in China. Over the past 15 years, the expert team from Chinese Academy of Sciences (CAS), together with Jilin Province’s agricultural sector, universities, local academies of science, and other related units, overcame the barrier of demonstration and extension of conservation tillage in black soil region in Northeast China. They developed high performance no-till planter and strip-tiller, and proposed the techniques of wide-narrow row no-till, strip-till, ridge-till in Northeast China. This innovative application of conservation tillage in Northeast China is called Lishu model, and the effects of its wide extension in Northeast China is prospected.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The black soil in northeast China presents a trend of thinning, hardening, impoverishment, and acidification under the long#2;term high-intensity utilization, and faces the water resources shortage and ecological environment imbalance. Thus, the coordination between soil and water resources and environment has become the bottleneck of sustainable agricultural development in northeast China. The black soil protection and utilization is not only a problem of cultivated land system itself, but also a problem of harmonization of mountain-river-forest-farmland-lake-grassland-sandy land ecosystem. To achieve the goal of sustainable use of the black soil, it is necessary to give full play to the function of soil and water conservation, wind prevention and sand fixation, and biodiversity of natural ecosystems such as woodlands, grasslands, and wetlands. Hence, in addition to taking actions to ensure the quantity of cultivated black soil and improve soil quality, a synergetic development strategy of the mountain-river-forest-farmland-lake-grassland-sandy land ecosystems should be implemented to build ecological barrier for controlling and remediation of the black soil degradation.
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-09 Cooperative journals: 《干旱区研究》
Abstract： 设置正常供水、轻度、中度和重度干旱处理，分析两年生榆树幼苗不同器官的可溶性糖、淀粉及非结构性碳水化合物（NSC）随处理时间延长（15、30、45 d和60 d）的变化特征。结果表明：水分处理15 d时，随着干旱程度增加，叶片和细根可溶性糖含量呈下降趋势，叶片淀粉含量在中度和重度干旱处理最低，为（18.35±0.06）mg·g-1，茎和粗根可溶性糖含量在重度干旱处理显著低于其他处理。处理30 d时，叶片淀粉和NSC含量随干旱程度增加呈上升趋势，且叶片淀粉含量在重度干旱处理最高，为（47.83±0.27）mg·g-1，茎和粗根淀粉及NSC含量在轻度干旱处理下显著低于适宜水分处理。处理45 d时，随干旱程度增加，细根可溶性糖/淀粉呈下降趋势，叶片可溶性糖含量、可溶性糖/淀粉和茎淀粉含量在重度干旱处理显著高于其他处理。处理60 d时，随着干旱程度增加，叶片和细根可溶性糖/淀粉逐渐增加，粗根可溶性糖、淀粉和NSC含量在重度干旱处理显著高于其他处理，并且NSC含量达到最大值（68.88±1.01）mg·g-1。以上结果表明，榆树幼苗各器官可溶性糖、淀粉及NSC含量随着处理时间延长做出不同的响应，各器官NSC下降，并在粗根中积累。这为科尔沁沙地榆树防护林的水分管理提供依据。
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Soil Science submitted time 2018-07-26
Abstract： "
Peer Review Status:
Awaiting Review
Subjects: Other Disciplines >> Synthetic discipline submitted time 2017-03-08 Cooperative journals: 《中国科学院院刊》
Abstract：文章从大数据特征分析入手，分析了国内外大数据在环境领域的发展状况，阐明了我国土壤环境大数据发展的数据基础与瓶颈问题，提出了土壤环境大数据系统的构建方法与技术流程；并根据国家大数据发展战略与土壤环境领域的行业需求，建议统筹建立土壤环境大数据云平台、管理平台和专题应用平台，提供面向区域尺度土壤环境管理、多主体跨介质协同治理和农产品安全保障的公共服务与创新应用产品。
Subjects: Biology >> Ecology submitted time 2017-02-09 Cooperative journals: 《生态学报》
Abstract：气候变化作为人类当前面临的最严峻挑战，已对生态脆弱区农户生计产生严重的负面影响，明确农户对气候变化的感知对于制定有效的气候变化适应政策非常关键。以甘南高原为研究区，基于入户调查数据，构建了农户对气候变化的感知度指数，分析了甘南高原农户的气候变化感知特征，并采用经济计量模型分析了影响农户气候变化感知的关键因素。结果表明：（1）甘南高原农户对气温变化的感知能力强于对降水变化的感知，并对近期发生的、规模较大、影响较严重的极端天气记忆较深；（2）农户对气候变化的严重性及可能性感知较强烈，感知到的适应成本与适应功效也较高，但感知到的自我效能较弱，其气候变化严重性、可能性、适应功效、自我效能及适应成本感知度指数分别为3.76、3.34、3.43、2.85、3.53，且农区农户对气候变化的风险感知与适应感知均最强，半农半牧区次之，纯牧区最弱；（3）气候变化信息、农户的客观适应能力、农户对社会话语的信任度、适应激励均会影响农户的气候变化感知，其中，适应激励为最关键的影响因素，其与农户的气候变化适应功效感知、自我效能感知均呈正相关，而与风险感知、适应成本感知呈负相关。最后，针对如何提高农户气候变化感知的准确度，增强农户应对气候变化的能力，提出相关的政策建议。
Subjects: Biology >> Botany >> Plant ecology, plant geography submitted time 2016-05-03
Abstract： Aims Forests represent the most important component of the terrestrial biological carbon pool and play an important role in the global carbon cycle. The regional scale estimation of carbon budgets of forest ecosystems, however, have high uncertainties because of the different data sources, estimation methods and so on. Our objective was to accurately estimate the carbon storage, density and sequestration rate in forest vegetation in Jilin Province of China, in order to understand the role of the carbon sink and to better manage forest ecosystems. Methods Vegetation survey data were used to determine forest distribution, size of area and vegetation types regionally. In our study, 561 plots were investigated to build volume-biomass models; 288 plots of shrubs and herbs were harvested to calculate the biomass of understory vegetation, and samples of trees, shrubs and herbs were collected to analyze carbon content. Carbon storage, density and sequestration rate were estimated by two forest inventory data (2009 and 2014), combined with volume-biomass models, the average biomass of understory vegetation and carbon content of vegetation. Finally, the distribution patterns of carbon pools were presented using ArcGIS soft ware. Important findings Understory vegetation biomass overall was less than 3% of the tree layer biomass, varying greatly among different forest types and even among the similar types. The carbon content of trees was between 45.80%–52.97%, and that of the coniferous forests was higher than that of the broadleaf forests. The carbon content of shrub and herb layers was about 39.79%–47.25% and 40%, respectively. Therefore, the vegetation carbon conversion coefficient was 0.47 or 0.48 in Jilin Province, and the conventional use of 0.50 would cause deviation of ±5.26%. The vegetation carbon pool of Jilin Province was at the upper range of regional carbon pool and had higher capacity of carbon sequestration. The value in 2009 and 2014 was 471.29 Tg C and 505.76 Tg C, respectively, and the total increase was 34.47 Tg C with average annual growth of 6.89 Tg C?a–1. The corresponding carbon sequestration rate was 0.92 t?hm–2?a–1. The carbon density rose from 64.58 t?hm2 in 2009 to 66.68 t?hm2 in 2014, with an average increase of 2.10 t?hm2. In addition, the carbon storage of the Quercus mongolica forests and broadleaved mixed forests, accounted for 90.58% of that of all forests. The carbon increment followed the order of young > over-mature > near mature > middle-aged > mature forests. The carbon sequestration rate of followed the order of over-mature > young > near mature forest> middle-aged > mature forests. Both the carbon increment and the carbon sequestration rate of mature forests were negative. Furthermore, spatially the carbon storage and density were higher in the east than in the west of Jilin province, while the carbon increment was higher in northeast and middle east than in the west. The carbon sequestration rate was higher in Tonghua and Baishan in the south, followed by Jinlin Province in the middle and Yanbian in the east, while Baicheng, Songyuan and Liaoyuan in west showed negative values.
Peer Review Status:Awaiting Review
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