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A New Carbon and Oxygen Balance Model Based on Ecological Service of Urban Vegetation

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Chinese Geographical Science 2010年第2期20卷 144-151页

作者： YIN Kai zhao qianjun LI Xuanqi CUI Shenghui HUA Lizhong LIN Tao Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Institute of Spatial Information Technology Xiamen University of Technology Xiamen 361024 China

The application of human induced oxygen consumption and carbon emission theory in urban region was summed up and on this base a new model of urban carbon and oxygen balance (UCOB) was constructed by calculating the carbon and oxygen fluxes. The purpose was to highlight the role of vegetation in urban ecosystems and evaluate the effects of various human activities on urban annual oxygen consumption and carbon emission. Hopefully,the model would be helpful in theory to keep the regional balance of carbon and oxygen,and provide guidance and support for urban vegetation planning in the future. To test the UCOB model,the Jimei District of Xiamen City,Fujian Province,China,a very typical urban region,was selected as a case study. The results turn out that Jimei′s vegetation service in oxygen emission and carbon sequestration could not meet the demand of the urban population,and more than 31.49 times of vegetation area should be added to meet the whole oxygen consumption in Jimei while 9.60 times of vegetation area are needed to meet the carbon sequestration targets. The results show that the new UCOB model is of a great potential to be applied to quantitative planning of urban vegetation and regional eco-compensation mechanisms.

关键词： ecological service carbon cycle oxygen cycle urban carbon and oxygen balance urban vegetation planning

Whole-genome sequencing reveals selection signals among Chinese,Pakistani,and Nepalese goats

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Journal of Genetics and Genomics 2023年第5期50卷 362-365页

作者： Yefang Li Ying Gong Zhengkai Zhang Ling Li Xuexue Liu Xiaohong He qianjun zhao Yabin Pu Yuehui Ma Lin Jiang Institute of Animal Sciences Chinese Academy of Agricultural SciencesBeijing 100193China CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100093China College of Animal Science and Technology Qingdao Agricultural UniversityQingdaoShandong 266109China Centre d’Anthropobiologie et de Genomique de Toulouse Universite Paul SabatierToulouse 31000France

The goat(Capra hircus)is one of the oldest domesticated animal species,with archeological evidence indicating that its earliest domestication from the wild ancestor(bezoar)occurred in the Fertile Crescent 10,000 calibrated calendar years ago(Zeder and Hesse,2000).A variety of well-adapted goat breeds with excellent economic traits have been selected artificially and naturally for human needs in China,Pakistan,and *** example,cashmere goat breeds produce fine cashmere wool and are mainly distributed on the Himalayan Plateau(e.g.,Nepal and Tibet)and in cold northern China(e.g.,Inner Mongolia and Liaoning).The Toggenburg dairy goat is the most productive breed of dairy goat and is distributed in at least 50 countries on all continents(Ferro et al.,2017).Pakistani ewes are reared mostly for meat and wool purposes,but some are used as dairy goats,such as the Bugi Toori goat and Pateri goat(Bilal et al.,2018).Additionally,indigenous goats of the southern Asian regions are well adapted to the local hot *** unique traits and biodiversity serve as genetic resources that can be used for the artificial breeding of ***,several studies have provided patterns of genome-wide characteristics in goat populations to explore the underlying genetic basis of trait formation and environmental adaptability in China(Zhang et al.,2018),Pakistan(Kumar et al.,2018),and Nepal(Sasazaki et al.,2021),***,due to the proximity of these geographic regions,the profiles of genetic differences,gene flow,and common genes related to high trait performance between goat populations from China,Pakistan,and Nepal remain unclear.

关键词： breeding adapted Whole

Dynamic analysis of urban spatial expansion and its determinants in Xiamen Island

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Journal of Geographical Sciences 2011年第3期21卷 503-520页

作者： LI Xinhu LIN Tao ZHANG Guoqin XlAO Lishan zhao qianjun CUI Shenghui Key Lab of Urban Environment and Health Institute of Urban Environment CAS Xiamen Key Lab of Urban Metabolism Xiamen 361021 Fujian China Institute of Remote Sensing Applications CAS Beijing 100101 China

Most of the world＇s cities are concentrated in coastal areas. As a special geographical component of the coastal system, island urban spatial expansion is the outcome of interactions between city development and the physical environment. This paper takes Xiamen Island, located in Southeastern China, as an example to analyze island urban spatial expansion and its determinants by combining an analysis of the literature on urban development policies, urban overall plans, population growth and industrial development, with geographical information analysis using historical maps and remote sensing photographs. Firstly, we reviewed the history of the Xiamen City development during the last 100 years, which can be divided into four periods： the embryonic modern city and early development from 1908 to 1949; administrative boundary expansion and infrastructure development from 1950 to 1979; special economic zone construction and rapid urbanization from 1980 to 2003; and Bay City construction since 2003. The dynamic changes to the coastline, island shape, built-up area, transportation, administrative division, and major land use type conversion which occurred during approximately the past 100 years were analyzed and the characteristics of the island urban spatial expansion were concluded： early expansion from a central point, followed by expansion along a section of coastline, and expansion from the coastline inland. Secondly, we discussed the potential determinants of island urban spatial expansion including administrative division adjustment, urban master planning revision, industrial development, topographical factors, coastal area reclamation, transportation expansion, and population growth. Finally, the effects of each potential determinant on island urban spatial expansion were concluded. Island urban spatial expansion is the result of a synthesis of natural and socio-economic factors which are not independent but interacting. Built-up area expansion is the major driver

关键词： island urbanization spatial expansion determinants Xiamen

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县域尺度农业资源管理决策支持系统研究

农业工程学报 2005年第4期21卷 123-126页

作者：赵千钧谢高地李军中国科学院地理科学与资源研究所北京100101

该文根据实际需要,在ArcView和FoxPro支持下建立了县域尺度的农业资源管理决策支持系统。它的组成不仅包括构成系统基础的土地资源、水资源、气候资源、生物资源,同时涉及依赖这些资源而存在的各种作物、牲畜、果木,以及为这些产品所投... 详细信息

该文根据实际需要,在ArcView和FoxPro支持下建立了县域尺度的农业资源管理决策支持系统。它的组成不仅包括构成系统基础的土地资源、水资源、气候资源、生物资源,同时涉及依赖这些资源而存在的各种作物、牲畜、果木,以及为这些产品所投入的生产资料。然后介绍了该系统在山东省宁津县的应用实例。县域农业资源管理决策支持系统将计算机和地理信息系统技术与当地自然地理、社会经济条件结合,根据相关的专家知识库,实现农业资源的合理利用,提高农业生产资料生产效率,同时还有效减轻农业生产造成的环境问题。

关键词：农业资源决策支持系统 GIS

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NA随机变量对数律的收敛速度

应用概率统计 2023年第5期39卷 659-666页

作者：邱德华赵倩君广东财经大学统计与数学学院广州510320

设{X,X_(n),n>1}是同分布的NA随机变量序列,h(·)>0是定义在(0,∞)上的不减函数且满足∫_(1)^(∞)[th(t)^(-1)dt=∞.令ψ(t)=∫_(1)^(t)[sh(s)]^(-1)ds,t≥1,S_(n)=Σ_(i=1)^(n)X_(i),n≥1,Lt=ln max{e,t}.本文证明了Σ_(n)^(∞)=1[nh(n)]^(-1)P(max_(1)≤j≤n|S_(j)|≥(1+ε)σ√2nLψ(n))0成立的充要条件是E(X)=0和E(X^(2))=σ^(2)∈(0,∞).这一结果部分地推广了文献[7]的结论.

关键词： NA随机变量对数律收敛速度

城市森林生态服务功能在城市景观规划中应用的思考

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地球科学进展 2010年第4期25卷 444-450页

作者：尹锴赵千钧赵煜中国科学院城市环境研究所福建厦门361021 中国科学院遥感应用研究所北京100101

回顾了景观规划的发展历程,并依据城市森林生态服务功能的内涵,指出当前国内外景观规划中存在的缺陷与不足。旨在通过对二者关系的分析,解读景观生态学理论引入规划中的功能缺失,以期重新唤起人们对于城市森林生态服务功能重要性的关注... 详细信息

回顾了景观规划的发展历程,并依据城市森林生态服务功能的内涵,指出当前国内外景观规划中存在的缺陷与不足。旨在通过对二者关系的分析,解读景观生态学理论引入规划中的功能缺失,以期重新唤起人们对于城市森林生态服务功能重要性的关注,并尝试将城市森林生态服务功能的研究成果应用于景观规划领域,为景观规划的定量化提供数据基础和科学依据。

关键词：城市森林生态服务景观规划景观格局生态学过程

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力量素质在散打运动中的作用及其训练

中国体育教练员 2002年第1期10卷 26-27页

作者：赵前军安徽省体育运动学校

1前言散打运动是一项以对方技击动作为转移的斗智、较技、较力"的对抗性项目.力量素质又是一切对抗性项目运动员的基本素质之一,俗话说:"一力降十会","一胆、二力、三功夫".都说明了力量素质在实战中起着非常重要的作用.它既是速度、耐... 详细信息

1前言散打运动是一项以对方技击动作为转移的斗智、较技、较力"的对抗性项目.力量素质又是一切对抗性项目运动员的基本素质之一,俗话说:"一力降十会","一胆、二力、三功夫".都说明了力量素质在实战中起着非常重要的作用.它既是速度、耐力、灵敏、柔韧的基础,也是掌握技术的必要条件.力量素质的发展往往影响到其它素质的发展,有时技术掌握运用的不够,主要就是因为部分力量不足造成的,所以力量素质练习就成为改进技术、提高成绩的关键.对于优秀运动员发展力量素质又是保持较高运动水平,进一步提高成绩的手段.在散打比赛中,两个运动员的技、战术水平和其它方面的条件基本接近时,谁有较好的力量素质,谁取得胜利的可能性就大,这就说明了在掌握专项技、战术的前提下,力量与成绩的提高是成正比的.本文就力量素质在散打运动中的作用及其训练方法进行探讨,以进一步促进散打运动水平的提高.

关键词：力量素质散打运动技击动作对抗性运动员实战训练作用转移灵敏

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切换网络控制系统鲁棒H;容错控制

机床与液压 2022年第1期50卷 144-149页

作者：赵千钧付兴建北京信息科技大学北京100192

研究一类具有参数不确定的网络化控制系统,同时考虑数据丢包和网络时延对系统性能产生的影响,将服从伯努利丢包的网络控制系统视为以一定速率切换的开关。针对既有传感器失效又有执行器失效的故障情形,引入一种状态反馈控制器,并基于Lya... 详细信息

研究一类具有参数不确定的网络化控制系统,同时考虑数据丢包和网络时延对系统性能产生的影响,将服从伯努利丢包的网络控制系统视为以一定速率切换的开关。针对既有传感器失效又有执行器失效的故障情形,引入一种状态反馈控制器,并基于Lyapunov理论和异步动态系统理论,对网络控制系统进行鲁棒容错控制问题的研究,给出系统在此情形下保持渐近稳定的充分条件,通过求解线性矩阵不等式,得到了执行器和传感器同时失效情况下的容错控制器。最后通过算例仿真证明了所提方法的有效性。

关键词：切换网络控制系统多故障并发状态反馈鲁棒容错

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丽江城市不同区域景观美学

生态学报 2014年第7期34卷 1794-1799页

作者：郭先华赵千钧崔胜辉吝涛李元云南农业大学资源与环境学院昆明650201 中国科学院城市环境研究所厦门361021 中国科学院遥感与数字地球研究所北京100094

我国正处在快速城市化阶段,古城或古镇正面临城市化和旅游业的双重压力,古城风貌和景观美学受到影响。以世界文化遗产丽江古城所在地——丽江盆地为研究对象,按照大研古镇-丽江新城-郊区的梯度设置评价样点,采用评分法(SBE-Scenic beaut... 详细信息

我国正处在快速城市化阶段,古城或古镇正面临城市化和旅游业的双重压力,古城风貌和景观美学受到影响。以世界文化遗产丽江古城所在地——丽江盆地为研究对象,按照大研古镇-丽江新城-郊区的梯度设置评价样点,采用评分法(SBE-Scenic beauty estimation procedure)进行景观美学评价。结果显示:参加评价的男性与女性显示出性别间的细小差异,两个曲线的趋势基本一致,其中最大值和最小值均由男性评价者产生。丽江古城的三大古镇中,束河古镇的景观美学评价值最高,为6.79,白沙古镇的景观美学评价值为5.82,大研古镇景观美学评价值为5.68。大研古镇与丽江新城交错带的景观美学评价均值为4.9,丽江新城区的平均值均值为4.03,玉龙县城的均值为3.88,评价分值最低点在玉龙新县城,为2.36。在世界文化遗产核心区大研古镇到郊区的梯度上,整个评价曲线呈V型,中间低,两边高的趋势,大研古镇与城市新区交错带的景观美学评价值较低。景观美学评分较高的景观要素包括:自然景观(山体、水体)、农田、古镇、有历史文化特色和地方民族特色的景观等,现代城市景观的评价值较低。研究结果对保护丽江古城具有重要意义,可以用来完善丽江城市景观规划、优化城市空间格局,在城市建设发展的同时,保护好丽江的古城风貌和田园风光,以维系景观美学价值。

关键词：世界文化遗产丽江古城景观美学城市化