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Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance 被引量:13
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作者 YUAN Wei-ling CAO Cou-gui LI Cheng-fang ZHAN Ming CAI Ming-li WANG Jin-ping 《Agricultural Sciences in China》 CAS CSCD 2009年第10期1246-1255,共10页
Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and thei... Rice-duck (RD) and rice-fish (RF) ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane (CH4) and nitrous oxide (N2O) emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials (GWPs), we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly (P〈 0.05) lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly (P〈0.05) higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK (5 997.6 and 5 391.5 RMB yuan ha^-1). Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits. 展开更多
关键词 methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem greenhouse effect economic benefit
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Function of Rural Settlement Complex Ecosystem in Mountain Area:A Case Study of Raosi Village of Zuogong County,Tibet 被引量:4
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作者 LIU Shaoquan CHEN Guojie 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期945-950,共6页
Using energy analysis,the quantifying evaluation and study method on production, living and ecology functions and their sustainability of rural settlement ecosystem in mountain area is established with these energy in... Using energy analysis,the quantifying evaluation and study method on production, living and ecology functions and their sustainability of rural settlement ecosystem in mountain area is established with these energy index such as export of labor and products, export of water resource, internal energy reserve, energy consumption for human living, net energy of ecosystem function and net internal reserve. Taking rural settlement Raosi Village in Hengduan Mountains as a case study, and on the basis of the synthetic research into the ecological process of the complex ecosystem, the study shows that energy costs of production, human living and ecology functions are separately taking 1.36%, 13.59% and 85. 05% of the gross ecosystem functions, and the exertions of production and human living functions are close to a high-point state on the present using level of energy in the settlement. The study also shows that the most important function of a rural settlement in mountain area is its ecological rather productive function. 展开更多
关键词 mountain area rural settlement complex ecosystem ecosystem function energy analysis
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Economic valuation of gas regulation as a service by rice-duck-fish complex ecosystem 被引量:10
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作者 Yuan Welling Cao Cougui Wang Jinping 《Ecological Economy》 2008年第3期266-272,共7页
Valuating the fimction of ecosystem services is crucial for accounting green GDP, making a conservation policy of ecological environment and the decision of regional development as well as sustainable development stra... Valuating the fimction of ecosystem services is crucial for accounting green GDP, making a conservation policy of ecological environment and the decision of regional development as well as sustainable development strategy. R ice-duck-fish symbiosis has been promoted in several developing countries as a way of increasing incomes for rice farmers, but investigations of its value have mainly focused on direct economic' benefits, such as food and raw material production. Few studies have been conducted on the estimation of indirect services provided by rice-duck-fish complex ecosystem. The gas regulation service and its economic values provided by rice-duck-fish complex ecosystem were studied in Wuhan, China. The major components of gas regulation are O2 emission and greenhouse gases (GHGs, CO2) regulation. The results show that O2 emission from different treatments (including rice-duck (RD), rice-fish (RF), rice-duck-fish (RDF) and rice (CK)) ranged from 26,370 kg/ha to 33,910 kg/ha per year. with an economic value of 10,050-12,920 yuan/ha per ),ear (Chinese currency: 1 euro =10.2475 yuan, August 28, 2007). The net GHGs exchange varied from 1,200 to 3,320 kg/ha per year; and its economic value ranged from 1,040 yuan/ha to 2,900 yuan/ha per year Consequently, the total economic value of gas regulation provided by symbiosis complex ecosystems ranged from 11,090 yuan/ha to 15,820 yuan/ha per year. and the maximum overall economic value of gas regulation was provided by RDF complex ecosystem. The work will be useful for further understanding of the functions of rice-duck-fish complex ecos.vstem services and supplying the theoretical references to agricultural policy. 展开更多
关键词 Eeosystem services Gas regulation GHGs emission: O2 emission Riee-duek-fish complex ecosystems
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The Citrate Metabolism in Homo-and Heterofermentative LAB:A Selective Means of Becoming Dominant over Other Microorganisms in Complex Ecosystems 被引量:2
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作者 Gemelas Laetitia Degraeve Pascal Demarigny Yann 《Food and Nutrition Sciences》 2014年第10期953-969,共17页
The citrate metabolism has been extensively studied in lactic acid bacteria (LAB) for its aroma compound production. Among the 4-carbon (C4) by-products obtained from citrate fermentation, diacetyl is one of the bette... The citrate metabolism has been extensively studied in lactic acid bacteria (LAB) for its aroma compound production. Among the 4-carbon (C4) by-products obtained from citrate fermentation, diacetyl is one of the better known products for its contribution to the buttery aroma of dairy products. A lot of documents deal with ways to improve diacetyl concentration in food matrices. Apart from these organoleptic advantages, in a microbial ecosystem, the citrate metabolism gives selective advantages to citrate positive microorganisms. Citrate metabolism allows the LAB to use another carbon source for their growth, withstand acidic conditions and generate a “proton motive force” (PMF). Moreover, the citrate/glucid co-metabolism leads to the fast release of organic compounds known for having bacteriostatic effects. Under specific conditions, the C4?pathway liberates diacetyl which is bacteriostatic. In this review we first describe the citrate metabolism and the enzymes involved in the two homo- and heterofermentative LABLc diacetylactisandLeuconostocspp. Moreover, the way to shift the metabolic pathway toward the production of aromatic compounds is discussed for both of these fermentative types of bacteria. Finally, the selective advantages of citrate metabolism for LAB in complex microbial ecosystems are delineated. 展开更多
关键词 Citrate Metabolism Lactococcus lactis subsp.lactis biovar.diacetylactis Leuconostoc spp. complex Microbial ecosystems Homo-and Heterofermentative Lactic Acid Bacteria
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Coupling and evolution mechanism of infrastructure mega-projects complex ecosystem: Case study on Hong Kong-Zhuhai-Macao Bridge
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作者 Zebin ZHAO Xiaolong XUE +2 位作者 Xinglin GAO Gang LIU Hengqin WU 《Frontiers of Engineering Management》 2018年第1期17-29,共13页
Infrastructure mega-projects(IMP), which involve complex interactions and feedback, have more significant impact on economic, social, and other systems.This paper proposes a concept—the IMP complex ecosystem—to anal... Infrastructure mega-projects(IMP), which involve complex interactions and feedback, have more significant impact on economic, social, and other systems.This paper proposes a concept—the IMP complex ecosystem—to analyze IMP from a broad perspective of organic links across engineering, social, economic, and resource environments. Moreover, this paper proposes the theoretical concept, framework, and functions for the IMP complex ecosystem based on complex ecosystem theory.First, the coupling process between IMP complex ecosystem subsystems is analyzed through material flows, energy flows, information flows, and value streams.Second, a logistic model of the IMP complex ecosystem is proposed by analyzing the evolution conditions and motivations. Third, the evolution pattern of the IMP complex ecosystem is determined. Fourth, the positive evolution strategy of the IMP complex ecosystem based on dissipative structure theory and the influencing factors of the evolutionary process is introduced. Finally, the Hong Kong-Zhuhai-Macao Bridge and Sousa chinensis are used as the case study. This paper also analyzes the coupling structure on the complex ecosystem of the Hong KongZhuhai-Macao Bridge and investigates the coupling and evolution mechanism application of the IMP complex ecosystem on Sousa chinensis protection for the Hong Kong-Zhuhai-Macao Bridge project. 展开更多
关键词 infrastructure mega-projects(IMP) Hong Kong-Zhuhai-Macao Bridge complex ecosystem coupling relationship evolution mechanism
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我国东部山地针阔混交林碳通量特征分析
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作者 孙彦坤 张胤洲 +6 位作者 姚维杰 叶京 张峻搏 潘小乐 刘兰忠 王自发 程雪玲 《中国环境科学》 EI CAS CSCD 北大核心 2024年第6期3492-3501,共10页
以浙江省金华市武义县大毛尖山为研究区域,开展复杂山地森林生态系统碳汇能力的观测研究,并利用涡动相关法在2022年6月~2023年5月进行观测,经过数据质量控制和质量评价分析,得到42%的优质CO_(2)通量数据.结果表明,大毛尖山周边以针阔混... 以浙江省金华市武义县大毛尖山为研究区域,开展复杂山地森林生态系统碳汇能力的观测研究,并利用涡动相关法在2022年6月~2023年5月进行观测,经过数据质量控制和质量评价分析,得到42%的优质CO_(2)通量数据.结果表明,大毛尖山周边以针阔混交林为主,能量闭合度为0.89,能够很好的代表站点通量情况.CO_(2)通量在日尺度上均表现为U型变化,范围为-1.20~0.89mgCO_(2)/(m^(2)·s).四季碳汇能力强弱依次为,夏季、春季、秋季、冬季;各月份净生态系统碳交换量(NEE)均为负值,整体表现为碳汇.CO_(2)通量与气象因子中的空气温度呈负相关,相对湿度和平均风速正相关,夜间因呼吸作用产生的CO_(2)通量与土壤温度正相关.本研究初步解释了大毛尖山森林生态系统的碳汇特征. 展开更多
关键词 CO_(2)通量 涡动相关法(EC) 净生态系统碳交换量(NEE) 森林生态系统 复杂地形
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高技能人才培养与产业需求适配模式研究——复杂适应系统视角 被引量:1
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作者 李萍 许红春 张京 《北京农业职业学院学报》 2024年第3期42-48,共7页
快速培养与产业需求相适配的高技能人才,需要构筑产业人才生态圈,并将各利益相关方凝结成命运共同体。命运共同体超越了一般意义上的利益共同体,是具有生命特质的复杂适应系统。由此构建适应性集群模式,为提升高技能人才培养与产业需求... 快速培养与产业需求相适配的高技能人才,需要构筑产业人才生态圈,并将各利益相关方凝结成命运共同体。命运共同体超越了一般意义上的利益共同体,是具有生命特质的复杂适应系统。由此构建适应性集群模式,为提升高技能人才培养与产业需求的适配性提供模型参照。适应性集群模式的内容包括目标、原则、适用领域、组成要素、运行方式、应用价值等,并给出实践建议。此模式创新之处在于关注到外部环境的重要作用,强调要符合适应性协同和动态集群的客观规律。 展开更多
关键词 高技能人才培养 适配产业需求 复杂适应系统 产业人才生态圈 命运共同体
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Exploration and Practice of Rubber Based Agroforestry Complex Systems in China
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作者 Dongling Qi Zhixiang Wu +4 位作者 Chuan Yang Zhongliang Tao Linlin Zhao Yingying Zhang Qingmao Fu 《Advances in Bioscience and Biotechnology》 2023年第12期479-491,共13页
Agroforestry ecosystems are constructed by simulating natural ecosystems, applying the principles of symbiosis in nature, and organizing multiple plant populations to coexist, while conducting targeted cultivation and... Agroforestry ecosystems are constructed by simulating natural ecosystems, applying the principles of symbiosis in nature, and organizing multiple plant populations to coexist, while conducting targeted cultivation and structural control scientifically. Rubber agroforestry complex ecosystems aim for sustainable development in terms of industry, ecology, resource utilization, and the livelihoods of producers. Rubber agroforestry complex ecosystems create a complex production structure system that integrates biology, society, and the economy through species combinations. Rubber trees and associated biological components coordinate with each other, mutually promote growth, and yield a variety of products for producers. Cultivation techniques and patterns of rubber agroforestry are essential components of these ecosystems. This study analyzes the production practices of rubber agroforestry complex cultivation, with a focus on the development and characteristics (complexity, systematicity, intensity, and hierarchy) of rubber agroforestry systems using a literature analysis and a survey approach. It explores the types and scales of complex planting, specifications and forms, and major effects of complex cultivation. This study identifies successful rubber agroforestry cultivation patterns and practical techniques, as well as the potential benefits of developing rubber agroforestry cultivation. It also points out the shortcomings in the development of complex planting, including an emphasis on production practices but insufficient theoretical research, a focus on production but inadequate attention to the market, and an emphasis on yield while overlooking the improvement of standards, brands, and added value. There are various complex patterns for young rubber plantations, but relatively fewer for mature plantations. Based on this analysis, this study suggests that future efforts should focus on in-depth research on interspecies and environmental interactions in rubber agroforestry ecosystems, clearly define key roles, accelerate the innovation of development patterns, and strengthen the foundation for development. It recommends promoting and demonstrating successful rubber agroforestry complex patterns and providing technical training, developing product branding for rubber agroforestry patterns, enhancing product value, expanding the application functions of rubber-forest mixed crop products, and establishing a stable and sustainable industry chain. This study provide practical experience and theoretical insights in rubber agroforestry complex systems from China the potential to enrich the knowledge of rubber agroforestry composite systems, provide practical experience to improve the operating income of smallholders, and even promote the sustainable development of rubber plantations. 展开更多
关键词 Rubber Tree (Hevea brasiliensis) Agroforestry ecosystem Rubber Intercropping complex Ecological Cultivation Land Resource
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基于生态位模型的县域乡村聚落用地适宜性评价
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作者 董秀明 《科技创新与应用》 2024年第16期116-119,共4页
现有县域乡村聚落用地适宜性评价方法的评价精度低,无法为县域乡村聚落用地合理划分与土地资源高效利用提供有利条件,因此引入生态位模型,开展对县域乡村聚落用地适宜性评价。从自然条件、资源条件、社会经济条件等方面选择出地质灾害... 现有县域乡村聚落用地适宜性评价方法的评价精度低,无法为县域乡村聚落用地合理划分与土地资源高效利用提供有利条件,因此引入生态位模型,开展对县域乡村聚落用地适宜性评价。从自然条件、资源条件、社会经济条件等方面选择出地质灾害、农用地质量、道路通达度等指标,完成对县域乡村聚落用地适宜性评价指标体系的构建。在此基础上,对各项适宜性指标量化。最后,结合生态位模型,构建适宜性评价模型,实现对用地适宜性的评价,确定不同适宜性程度用地区域的具体分布。通过对比实验证明,新的评价方法得到的评价结果更符合实际,评价精度更高,评价结果可为实现用地区域划分提供有利条件。 展开更多
关键词 生态位模型 县域乡村聚落 适宜性评价 自然条件 复杂生态系统
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企业生态机制的内容框架与演化模式——基于质性元分析的发现
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作者 吴炯 朱磊 《管理案例研究与评论》 北大核心 2024年第4期541-561,共21页
当前企业生态系统的研究重点仍在于突破其“隐喻的面纱”,挖掘其独特的运行原理。但现有文献面向不同的商业情境形成了不同的研究倾向,并不能表达出企业生态机制的全貌。同时鉴于当前研究仍以案例研究为主,基于质性元分析法,筛选出31篇... 当前企业生态系统的研究重点仍在于突破其“隐喻的面纱”,挖掘其独特的运行原理。但现有文献面向不同的商业情境形成了不同的研究倾向,并不能表达出企业生态机制的全貌。同时鉴于当前研究仍以案例研究为主,基于质性元分析法,筛选出31篇生态系统研究的案例论文,通过结构化编码过程,整理出企业生态机制的完整要素构成,从要素间的逻辑关系中发现:(1)案例支持企业生态系统具有价值共创机制、资源竞合机制及惯例协调机制等三种生态机制;(2)三种生态机制具有相同的内容框架,均可从生态场域和生态行为两方面刻画;(3)三种生态机制的演化均具有复杂属性,表现出非线性迭代、自发性涌现及开放性适应的演化模式。研究结论为企业生态系统研究在一个比较完整的理论框架下发展提供了新线索。 展开更多
关键词 企业生态系统 生态机制 质性元分析 复杂系统理论
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可持续生态学视角下生态产品价值实现的思路
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作者 张盛 李宏伟 +6 位作者 吕永龙 张二进 张杰 王溢晟 周云桥 杨逸夫 郝吉明 《中国人口·资源与环境》 CSCD 北大核心 2024年第6期151-160,共10页
生态产品价值实现是工业文明向生态文明过渡的产物,是“绿水青山就是金山银山”理念的重要实践。中国在生态产品价值实现的实践探索和理论研究中注重生态产品价值转化,但在一定程度上忽视了生态产品价值可持续实现的问题,导致生态产品... 生态产品价值实现是工业文明向生态文明过渡的产物,是“绿水青山就是金山银山”理念的重要实践。中国在生态产品价值实现的实践探索和理论研究中注重生态产品价值转化,但在一定程度上忽视了生态产品价值可持续实现的问题,导致生态产品价值实现在理念认知、保护修复、产业发展、部门协同、价值共享等方面出现了不可持续的趋势。可持续生态学在生态产品价值实现过程中扮演着核心角色,它不仅关注人类社会经济活动与自然生态系统之间的矛盾,而且致力于探索两者协调发展的可行路径。该研究基于可持续生态学的发展度-协调度-持续度的三维评价体系,采用文本分析与案例研究相结合的方法,以可持续发展理论为指导,结合社会-经济-自然复合生态系统的内在逻辑,综合考虑质量、动力和公平三个关键要素,构建了生态产品价值可持续实现的理论分析框架。该理论分析框架着重关注生态产品价值实现的全过程,特别遵循三个基本原则:在前端,与2030年联合国可持续发展目标(SDGs)紧密对接,确保生态产品价值实现与全球可持续发展议程同步;在中端,尊重地域差异性,将地方实践与生态产品价值的转化相结合;在末端,实现生态产品价值的均等共享,与社会持续公平系统相衔接,确保代际公平。基于生态产品价值可持续实现的理论分析框架,提出中国生态产品价值可持续实现的推进思路,即深挖动力要素以支撑健康发展、注重质量元素以调动多方协调、考虑公平元素以确保代际均衡,为促进生态产品价值可持续实现,促进生态文明建设,实现人与自然和谐共生的现代化提供科学依据。 展开更多
关键词 可持续生态学 复合生态系统 生态产品 价值实现 可持续发展目标(SDGs)
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2001-2020年东海区大陆海岸带复合生态系统韧性时空演变
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作者 张海涛 李加林 刘永超 《海洋通报》 CAS CSCD 北大核心 2024年第1期127-139,共13页
海岸带是自然、社会、经济相互作用频繁的地区,然而,过度开发胁迫海岸带生态环境退化。海岸带复合生态系统韧性研究有利于实现精准有效的生态保护。本文综合多源数据从复合生态系统基底状态、社会经济发展与资源环境禀赋的耦合协调关系... 海岸带是自然、社会、经济相互作用频繁的地区,然而,过度开发胁迫海岸带生态环境退化。海岸带复合生态系统韧性研究有利于实现精准有效的生态保护。本文综合多源数据从复合生态系统基底状态、社会经济发展与资源环境禀赋的耦合协调关系、复合生态系统的可持续发展潜力、人类活动对环境的影响范围与强度方面构建评价体系,定量评估2001-2020年东海区大陆海岸带复合生态系统韧性,分析韧性时空演变特征与空间分异的影响因素。结果表明:(1)2001-2020年东海区大陆海岸带复合生态系统韧性呈波动下降趋势,韧性空间异质性显著,具有明显的海陆梯度地带性。(2)林地是维持区域复合生态系统韧性的主体。(3)反映人类活动分布与强度的因素对复合生态系统韧性的影响越来越大。研究为保护、恢复、促进海岸带复合生态系统可持续利用与管理提供了理论支持与实践参考。 展开更多
关键词 复合生态系统 韧性 评价体系 东海海岸带
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祁连山地区复合生态系统韧性时空演化及障碍因子识别 被引量:2
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作者 刘玒玒 刘书芳 《干旱区地理》 CSCD 北大核心 2024年第2期237-247,共11页
祁连山地区是我国重要的生态功能区,也是我国生态环境脆弱区之一,研究祁连山地区自然-经济-社会复合生态系统韧性,以期有效治理祁连山地区生态环境问题。构建三维空间矢量模型、耦合协调模型和障碍度模型,测度2007—2021年祁连山地区复... 祁连山地区是我国重要的生态功能区,也是我国生态环境脆弱区之一,研究祁连山地区自然-经济-社会复合生态系统韧性,以期有效治理祁连山地区生态环境问题。构建三维空间矢量模型、耦合协调模型和障碍度模型,测度2007—2021年祁连山地区复合生态系统韧性和子系统耦合协调性,揭示影响复合生态系统韧性提升的障碍因子,并借助地理信息系统技术分析复合生态系统韧性的空间演化过程。结果表明:(1)祁连山地区复合生态系统韧性呈上升趋势,空间上呈现从东部逐渐向西部降低的趋势;自然子系统韧性呈下降趋势,空间上呈现中东部向西北部逐渐降低的趋势;经济子系统韧性呈上升趋势,且增速较快,高经济韧性集中分布于东部和北部;社会子系统韧性上升幅度不大,高社会韧性集中分布于东部。(2)祁连山地区复合生态系统韧性耦合度提升明显,已达到高水平耦合;耦合协调度呈波动上升,已达到中级协调等级。(3)自然子系统对复合生态系统韧性提升影响较大,来自经济子系统的指标障碍度提升明显。 展开更多
关键词 复合生态系统韧性 三维空间模型 耦合协调度 障碍因子 祁连山地区
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An ecosystem-based understanding and analysis for SENCE toward sustainable development 被引量:4
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作者 CHENG Sheng\|tong, HOU Ji\|xiong , JIA Hai\|feng (Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第3期328-332,共5页
There is a need to find a comprehensive approach focusing on the conflicts between economical growth and environmental protection. Chinese scholars advocate a comprehensive ecosystem viewpoint named social-economic-na... There is a need to find a comprehensive approach focusing on the conflicts between economical growth and environmental protection. Chinese scholars advocate a comprehensive ecosystem viewpoint named social-economic-natural complex ecosystem(SENCE). The kernel of the concept lies in the hierarchical structure of SENCE, through which methods from ecological network can be useful to the compound system. The author gives a schema depicting its structure, following a made analysis to help understand the reliance of economy on ecosystem. It is obvious that more actions should be done to strive for sustainable development. 展开更多
关键词 social-economic-natural complex ecosystem (SENCE) ecosystem model sustainable development
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海洋经济生态系统构建新方法——以海南为例
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作者 高一兰 黄晓野 《中国国土资源经济》 2024年第6期48-58,共11页
文章根据复杂经济思想构建了海南自贸港海洋经济生态系统,即海洋产业、海洋生态及海洋相关产业与政策在自贸港制度集成创新中一体化协同发展的开放型系统。研究结果表明,海南自贸港海洋经济具有典型的复杂经济生态系统特征,海洋产业发... 文章根据复杂经济思想构建了海南自贸港海洋经济生态系统,即海洋产业、海洋生态及海洋相关产业与政策在自贸港制度集成创新中一体化协同发展的开放型系统。研究结果表明,海南自贸港海洋经济具有典型的复杂经济生态系统特征,海洋产业发展要与海南自贸港产业链、供应链、生态链、价值链融和共生,创造海洋经济新价值;海洋经济发展要与海洋生态环境保护治理协同,在高质量发展海洋产业的同时促进形成以人为本的海洋生态文化;海南自贸港政策优势可进一步转化为海洋经济生态系统的内外部环境优势,应重视战略性新兴海洋产业发展,培育海洋经济新的增长点。 展开更多
关键词 海洋经济生态系统 海洋产业 海南自贸港 复杂经济思想
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土壤微生物网络复杂性预测黄土高原造林恢复生态系统多功能性
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作者 董政宏 张君红 +6 位作者 何佳 王健宇 李玉玉 冀泳標 刘凯茜 王振刚 陈文青 《生态学报》 CAS CSCD 北大核心 2024年第6期2544-2560,共17页
人类活动导致黄土高原土地退化和生物多样性丧失,进而降低了生态系统功能。人工造林是该区域退化土地恢复的重要措施。现有的生态修复研究通常侧重于微生物群落物种多样性的恢复对单一生态系统功能的影响,而忽略了微生物间存在的相互作... 人类活动导致黄土高原土地退化和生物多样性丧失,进而降低了生态系统功能。人工造林是该区域退化土地恢复的重要措施。现有的生态修复研究通常侧重于微生物群落物种多样性的恢复对单一生态系统功能的影响,而忽略了微生物间存在的相互作用与生态系统多功能性(Ecosystem multifunctionality,EMF)的关系。为探究造林恢复过程中土壤微生物多样性和网络复杂性与EMF的关系,本研究采用时空代换法(space-time substitution method),沿50年造林恢复时间序列,分析了黄土高原地区造林恢复对土壤微生物群落多样性、土壤微生物网络复杂性以及与土壤养分循环相关的10个生态系统功能指标的影响,明确了土壤微生物群落特征与EMF的关系。结果表明,随造林恢复时间序列的增加,土壤微生物群落的综合多样性、网络复杂性和EMF均呈现出显著增加后下降的趋势(P<0.05),其中土壤微生物综合多样性和网络复杂性在第8年达到最高值,EMF在第20年达到最大值。在未控制土壤环境因素时,细菌和古菌多样性与EMF无显著相关性,真菌多样性与EMF呈显著正相关(P<0.001);土壤微生物群落的综合多样性和网络复杂性均与EMF显著正相关(P<0.001),其中土壤微生物网络复杂性对EMF的解释度更高。通过偏回归分析(Partial least squares regression,PLSR)控制土壤因子影响后发现,尽管土壤微生物的综合多样性和网络复杂性对EMF的解释度(P<0.001)均降低,但土壤微生物网络复杂性对EMF的解释度仍高于微生物综合多样性。结构方程模型(Structural Equation Model,SEM)进一步分析表明,土壤微生物多样性通过土壤微生物网络复杂性对造林修复地的EMF产生间接影响。综上所述,相较于土壤微生物综合多样性,微生物网络复杂性能够更好地预测EMF。而且,土壤微生物综合多样性主要通过促进网络复杂性间接正向影响EMF。本研究揭示了造林恢复生态系统中微生物群落特征与EMF的关系,为退化修复生态系统功能恢复提供了新的微生物调控机制解析。 展开更多
关键词 造林恢复 微生物多样性 共现网络分析 网络复杂性 生态系统多功能性
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珠三角创新生态系统韧性的空间演化及影响因素——基于知识复杂性视角
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作者 罗欣然 夏丽丽 +1 位作者 张佳锃 安琳 《热带地理》 CSCD 北大核心 2024年第7期1300-1313,共14页
从维稳性、适应性和转型性3个维度构建区域创新生态系统韧性测度框架,探究2010—2020年珠三角创新生态系统韧性的空间演化及知识复杂性对区域创新生态系统韧性的影响。结果表明:1)知识复杂性通过知识子集类型的多样性、子集间的相互依... 从维稳性、适应性和转型性3个维度构建区域创新生态系统韧性测度框架,探究2010—2020年珠三角创新生态系统韧性的空间演化及知识复杂性对区域创新生态系统韧性的影响。结果表明:1)知识复杂性通过知识子集类型的多样性、子集间的相互依赖性和知识空间粘性、吸收和竞争效应影响系统韧性;2)2010—2020年珠三角创新生态系统韧性显著提升,逐步形成以深圳、广州为核心,中部高、东西部低的空间格局,中部和东西部韧性差异日益显著;3)不同韧性维度空间呈现中部地区维稳性、适应性较高,东部地区转型性较高,西部地区3个维度的韧性均较低的空间格局,其中,维稳性呈现“中部高、东西部低”的稳定结构,适应性呈现“中北和中东部高、中南和东、西部低”的稳定结构,转型性呈现“中、东部高、西部低”演变为“中东部、东部高、中西部和西部低”的发展态势;4)知识复杂性对珠三角创新生态系统韧性具有显著正效应,对系统维稳性、适应性的影响显著为正,对转型性的影响显著为负,知识复杂性通过促进产业结构升级、技术进步和政策环境优化对珠三角创新生态系统韧性产生显著的正向影响。 展开更多
关键词 区域创新生态系统 韧性 知识复杂性 空间演化 影响因素 珠三角地区
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MDCPD:基于矩阵序列距离度量的数字生态变点检测
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作者 朱业琪 刘明义 +1 位作者 苏统华 王忠杰 《计算机学报》 EI CAS CSCD 北大核心 2024年第10期2452-2465,共14页
数字生态系统是一个分布式的、适应性的、开放的社会技术系统.随着大数据、物联网、云计算等技术的发展,数字生态的表现形式逐渐复杂多样,与人们的生活更加密切.数字生态受内外部激励自发性地持续演化,一些事件的发生可能会使数字生态... 数字生态系统是一个分布式的、适应性的、开放的社会技术系统.随着大数据、物联网、云计算等技术的发展,数字生态的表现形式逐渐复杂多样,与人们的生活更加密切.数字生态受内外部激励自发性地持续演化,一些事件的发生可能会使数字生态的部分性质显著变化,偏离其正常的演化路径,进而导致生态伴随着异常不健康地发展,如果能够及时发现这些变化并定位引起变化的事件,然后加以人为干预,则可能将负面影响降到最低.动态复杂网络是一个辅助观测数字生态的有效工具,这使分析生态的演化情况成为可能,复杂网络分析领域中的变点检测是检测数字生态演化变点的主要技术手段之一.然而,目前已有的通用的变点检测方法未针对数字生态做出优化,忽视了数字生态的高度动态等特性,会导致这些方法可能无法在高度动态、持续变化的情况下检测变点,于是,已有方法在数字生态场景上的变点检测性能可能不佳.为解决上述问题,本文提出基于矩阵序列距离度量的数字生态变点检测方法(MDCPD),MDCPD是社区感知的,它从数字生态的社区视角观测数字生态的变化幅度,通过计算社区矩阵距离变化率在在连续时间动态网络建模的数字生态上高效地实现了变点检测,且变点检测和数字生态演化动因定位均是事件级别,能帮助生态的管理人员高效地进行干预和决策.为抵抗社区结构矩阵序列数据中的噪声对方法的影响,本文提出了矩阵干预策略,通过从数字生态中观测到的客观条件干预社区结构矩阵的数值,提高了社区结构矩阵序列对数字的生态结构表达能力.本文在基于合成数据的连续时间和离散时间两个场景的对比实验以及消融实验证明了MDCPD和矩阵干预策略的有效性,MDCPD的F1指标至多超过SOTA方法0.383,矩阵干预策略至多使MDCPD的F1指标提高了0.053.最后,本文在真实数字生态数据集上进行了案例分析,进一步说明了MDCPD的实践价值. 展开更多
关键词 数字生态 变点检测 动态网络 复杂网络分析 异常检测
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基于生态系统服务功能价值簇的复合型产业模式设计——以河北省阜平县为例
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作者 耿傲淼 张贵军 +1 位作者 徐磊 张蓬涛 《水土保持研究》 CSCD 北大核心 2024年第1期417-426,439,共11页
[目的]基于土地利用多功能特性构建复合型产业模式,为提高山区县的土地利用效率,推进区域生态与经济的高质量发展提供方法和参考。[方法]以太行山中段的阜平县为例,选取水源供给、保持土壤等9类生态系统服务功能作为评判阜平县土地多种... [目的]基于土地利用多功能特性构建复合型产业模式,为提高山区县的土地利用效率,推进区域生态与经济的高质量发展提供方法和参考。[方法]以太行山中段的阜平县为例,选取水源供给、保持土壤等9类生态系统服务功能作为评判阜平县土地多种功能空间集聚特征的依据,通过空间聚类分析得到不同的功能价值簇,并调整形成生态系统服务主导功能价值分区;在此基础上,叠加土地利用现状、地形地貌和现有产业发展布局,构建复合型产业发展模式。[结果](1)将研究区按生态系统服务功能价值的空间集聚特征分为6种功能价值簇;(2)调整各簇边界,形成维持生物多样性+提供美学景观+保持土壤区、提供美学景观+水源供给+原材料生产区等6类生态系统服务主导功能价值区;(3)在生态系统服务主导功能价值区的基础上,设计出“旅游业+文化产业”“智慧农业+旅游业”等7种复合型产业发展模式,可为实现阜平县乡村振兴与高质量发展提供新的驱动力。[结论]复合型产业模式的设计能够实现生态保护与经济发展的双驱并进,可为解决山区县生态保护与经济发展的矛盾问题提供案例参考。 展开更多
关键词 土地利用多功能 生态系统服务功能价值簇 复合型产业 聚类分析 阜平县
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Integrated Ecosystem Sustainability Approach: Toward a Holistic System of Thinking of Managing Arid Ecosystems
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作者 Meshal M. Abdullah Amjad T. Assi Nasser B. Asadalla 《Open Journal of Ecology》 2019年第11期493-505,共13页
Ecosystems in arid regions play a pivotal role in providing services to vulnerable environments with considerable challenges including extreme temperatures, low precipitation, variable climate change, and infertile so... Ecosystems in arid regions play a pivotal role in providing services to vulnerable environments with considerable challenges including extreme temperatures, low precipitation, variable climate change, and infertile soil. The countries of the arid regions are facing more challenges due to land degradation, biodiversity loss, the scarcity of water and food resources, and protecting their inhabitant’s public health. In many cases, policymakers in these countries are aware of the challenges, but they are seeking through scientific communities to develop clear sustainability and resiliency plans. Due to the complexity associated with arid ecosystem services, the scientist communities are still focusing on the development of integrated ecosystem management approaches. Within this line of commitment to our future generation, the paper in hand presents a framework for an Integrated Ecosystem Sustainability Approach (IESA). The core of this nexus approach is to understand and quantify the interlinkages between the ecosystem components, internal and external stresses, and society needs. The paper also identifies the key gaps to be considered when applying the IESA approach to arid ecosystem management plans. 展开更多
关键词 INTEGRATED ecosystem Sustainability APPROACH (IESA) ecosystem Services ARID and SEMI-ARID ecosystem ecosystem complexity ecosystem NEXUS
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