Discussion on the ecological theory and technological approaches of ecosystem quality improvement and stability enhancement.

Improving ecosystem quality and stability is one of the urgent tasks of national ecological environment construction. However, the ecological theory of ecosystem quality and stability has not been well clarified. Based on the summary of influencing factors and interaction between ecosystem quality and stability, we discussed the ecolo-gical theory on the evolution of ecosystem quality and stability from the perspectives of self-organization of biological agglomeration and structure nesting, correlation of ecological elements and coupling of ecological processes, ecosystem integrity and function emergence, ecological service spillover and efficiency tradeoff, synergy and interactions between resource supply capacity and environmental suitability, as well as interactions between spontaneous change and human activities. Technologies approaches and management strategies were proposed from the aspects of ecosystem macro-pattern adjustment, protected natural areas system construction, regional complex ecosystem comprehensive management, degraded ecosystem restoration, damaged ecosystem reestablishment, typical ecosystem process management.

Mapping Chinese annual gross primary productivity with eddy covariance measurements and machine learning.

Annual gross primary productivity (AGPP) is the basis for grain production and terrestrial carbon sequestration. Mapping regional AGPP from site measurements provides methodological support for analysing AGPP spatiotemporal variations thereby ensures regional food security and mitigates climate change. Based on 641 site-year eddy covariance measuring AGPP from China, we built an AGPP mapping scheme based on its formation and selected the optimal mapping way, which was conducted through analysing the predicting performances of divergent mapping tools, variable combinations, and mapping approaches in predicting observed AGPP variations. The reasonability of the selected optimal scheme was confirmed by assessing the consistency between its generating AGPP and previous products in spatiotemporal variations and total amount. Random forest regression tree explained 85 % of observed AGPP variations, outperforming other machine learning algorithms and classical statistical methods. Variable combinations containing climate, soil, and biological factors showed superior performance to other variable combinations. Mapping AGPP through predicting AGPP per leaf area (PAGPP) explained 86 % of AGPP variations, which was superior to other approaches. The optimal scheme was thus using a random forest regression tree, combining climate, soil, and biological variables, and predicting PAGPP. The optimal scheme generating AGPP of Chinese terrestrial ecosystems decreased from southeast to northwest, which was highly consistent with previous products. The interannual trend and interannual variation of our generating AGPP showed a decreasing trend from east to west and from southeast to northwest, respectively, which was consistent with data-oriented products. The mean total amount of generated AGPP was 7.03 ± 0.45 PgC yr-1 falling into the range of previous works. Considering the consistency between the generated AGPP and previous products, our optimal mapping way was suitable for mapping AGPP from site measurements. Our results provided a methodological support for mapping regional AGPP and other fluxes.

Eddy covariance-based differences in net ecosystem productivity values and spatial patterns between naturally regenerating forests and planted forests in China.

Net ecosystem productivity (NEP), the difference between gross primary productivity (GPP) and ecosystem respiration (ER), is the basis of forest carbon sinks. Revealing NEP differences between naturally regenerating forests (NF) and planted forests (PF) can benefit for making carbon neutrality strategies. Based on 35 eddy covariance measurements in China, we analyzed NEP differences in values and spatial patterns between NF and PF. The results showed that NF had slightly lower NEP than PF, resulting from the high stand age (SA) and soil fertilizer, while their differences were not significant (p > 0.05). The increasing latitude decreased mean annual air temperature thus decreased GPP both in NF and PF. However, the higher SA and soil fertilizer in NF made most GPP release as ER thus induced no significant NEP spatial variation, while lower SA and soil fertilizer in PF made NEP spatially couple with GPP thus showed a decreasing latitudinal pattern. Therefore, stand characteristics determined the differences in NEP values but indirectly affected the differences in NEP spatial variations through altering GPP allocation. The decreasing latitudinal pattern of NEP in PF indicates a higher sequestration capacity in the PF of South China. Our results provide a basis for improving the forest carbon sequestration.

[Ecological economics foundation research on ecological values, ecological asset management, and value realization: Scientific concepts, basic theories, and realization paths]. / è‡ªç„¶ç”Ÿæ€ä»·å€¼ã€ç”Ÿæ€èµ„äº§ç®¡ç†åŠä»·å€¼å®žçŽ°çš„ç”Ÿæ€ç»æµŽå­¦åŸºç¡€ç ”ç©¶­­ç§‘学概念、基础理论及实现途径.

Ecosystems provide various environmental conditions and natural resources for life, production, and human livelihoods. Ecosystem management based on natural laws is the basic way for human society to recognize the value of nature and ecosystems, protect and utilize the natural environment and resources, create and accumulate ecological assets, and sustainably develop. Taking that as one of the core concepts, regional ecological economics or economic ecology is becoming a frontier in scientific research to evaluate the Anthropocene earth system and sustainable development. From the perspective of macro-ecosystem science, based on the multi-functionality and multi-values of ecosystems, this study expounded the concepts of natural ecological value, ecological assets, ecological products, and some related phrases, analyzed the processes and principles of formation and change of ecological assets, production and consumption of ecological products, ecological investment, and profit and loss of ecological assets based on integrated ecology, sociology, and economics, proposed paths of regional ecological asset management and ecological value realization. It would provide theoretical and methodological references for the evaluation of regional ecosystem value and ecological assets, and the development of ecological industries and ecological value realization systems.

[Discussion on the ecological theory and assessment methods of ecosystem quality and its evolution]. / ç”Ÿæ€ç³»ç»Ÿè´¨é‡åŠå ¶çŠ¶æ€æ¼”å˜çš„ç”Ÿæ€å­¦ç†è®ºå’Œè¯„ä¼°æ–¹æ³•ä¹‹æŽ¢ç´¢.

Ecological civilization construction and ecological environment governance are basic tasks of state gover-nance in China. China has clearly put forward the goal of improving ecosystem quality and stability. However, there are no consensus on the scientific concept of ecosystem quality and the assessment methods of ecosystem quality evolution, which has puzzled the academic community. Based on the summarization of the scientific concept of ecosystem quality and its evolution, we discussed the concept of ecosystem quality and its ecological theory basis by referencing the concept of production quality, quality management and quality assessment of material production. The scientific connotation of ecosystem quality and its evolution was discussed from the perspectives of ecosystem natural attribute-social attribute-economic attribute and the relationships between them, the cascade relations of ecosystem component-structure-process-function-service-efficacy, the feedback of factor-system-environment, and the logic relation of state ecosystem fluctuation-quantity variation-quality alternation. We proposed perspectives and approaches of multi-objective assessment of ecosystem quality alternation from the aspects of natural resource environment system, typical ecosystem, regional macro-ecosystem, and ecological engineering efficacy.

[Discussion on the scientific concepts of regional resources and environmental carrying capacity and its ecological basis.] / åŒºåŸŸèµ„æºçŽ¯å¢ƒæ‰¿è½½åŠ›ç§‘å­¦æ¦‚å¿µåŠå ¶ç”Ÿæ€å­¦åŸºç¡€çš„è®¨è®º.

The carrying capacity of resources and environment is an essential concept in ecology, the theoretical and practical research of which has become an important basis for measuring regional sustainable development. However, the scientific connection between the ecological foundation and the carrying capacity of resources and environment is still unclear. Moreover, it remains unknown which ecological theories played a supporting role in the development of the resources and environment carrying capacity, which makes the scientific concept of carrying capacity very vague. Based on the discussion of the scientific concepts and development of the carrying capacity of resources and environmen, we systematically discussed the basic concepts, such as the niche volume that organisms can occupy, the ecological threshold of ecosystems to withstand environmental stress, the potential resource capacity (supply capacity) of sustainable supply such as climate, water and nutrition, and the environmental capacity of buffering and purifying pollutants. Furthermore, from the biophysical point perspective of foundation pressure bearing capacity, spatial capacity carrying capacity and ecological threshold carrying capacity, the scientific concepts of Natural Resources Supply Carrying Capacity (NRSCC), Nature Environment Carrying Capacity (NECC), Carrying Capacity of Biological Population Development (CCBPD), Carrying Capacity of Social and Economic Development (CCSED) and Carrying Capacity of Environmental Stress in Ecosystems (CCESE) were defined. Finally, three basic issues of ecology were discussed in detail, including the theory of population growth and the ecological capacity of the ecosystem, the theory of ecosystem multi-functionality and resource and environmental effects, and the theory of alternative stable states, self-adaptability, and self-organization. Based on exploring the theory and method of regional resource environmental assessment, this study would provide theoretical basis for regional resource environment utilization, protection and social and economic sustainable development.

[Evaluation theory and method of regional resources and environmental carrying capacity.] / 区域资源环境承载力的评价理论及方法讨论.

Our understanding of resources and environmental carrying capacity is deepened with the comprehensive effects of human needs and external stress. When human survival and development mainly depend on the supply of local resources and environmental conditions, the resources and environmental carrying capacity is largely controled by the dominant limiting factors. With sustainable development and environmental protection, the resources and environmental carrying capacity has gradually changed from supply restriction to demand support. There is an expression of capacity, threshold, intensity, and ability to characterize the resources and environmental carrying capacity. The impact of climate change and human activities on the resource and environmental system is increasing, altering resources and environmental carrying capacity. At present, the interrelationship and internal mechanism among resource and environmental carrying capacity, ecosystem vulnerability, and climate change risk are still unclear, which restricts the further development of theory and method. We preliminarily summarized and discussed the basic theory and method system of the research on carrying capacity of regional resources and environment. Furthermore, we advocated to develop the cascade relations of "carrying capacity of biological population development-carrying capacity of environmental stress in ecosystems-natural resources supply carrying capacity-natural environment carrying capacity-carrying capacity of social and economic development". Moreover, the calculation method and conceptual model of multi-dimensional resource and environmental carrying capacity were put forward under each concept framework. This study provided new ideas for the research on the method of resources and environment carrying capacity.

[Research advances in critical transition and its ecological mechanisms of terrestrial ecosystems.] / é™†åœ°ç”Ÿæ€ç³»ç»Ÿä¸´ç•Œè½¬æ¢ç†è®ºåŠå ¶ç”Ÿæ€å­¦æœºåˆ¶ç ”ç©¶è¿›å±•.

With the exacerbating disturbances of climate changes and human activities to terrestrial ecosystems, more and more studies realize that ecosystems are at the risk of shifts without warning in structural and functional states and recovery from perturbations require more time. Developing an early warning model to identify critical transition and understanding its ecological mechanism of typical ecosystems have become hotspot in ecological researches. At present, based on theoretical and experimental researches across multiple spatiotemporal scales, a variety of theoretical frameworks and indicators of early warning signals (EWSs) were proposed to signal terrestrial ecosystem critical transition. Here, in order to more thoroughly understand and construct theoretical frameworks and indicators of early warning signals, we reviewed advances in critical transitions from aspects of theoretical methods and processing mechanisms. Catastrophe theory and critical slowing down (CSD) are the two basic theories for early-warning ecosystem state transitions. Self-organization and feedback mechanisms are the primary ecological mechanisms to shape alternative stable state. Understanding cascade effects networks (CENet) among biological and environmental elements, and clarifying the equilibrium relationships between input and output of key ecosystem parameters are theoretical foundation of critical transition model. These theoretical cognitions could provide useful references to early warning of ecosystem disasters, ecological environment management and restoration.

[Theories of ecosystem vulnerability, adaptability and catastrophe based on the mechanisms of ecological succession.] / 基于生态系统演变机理的生态系统脆弱性、适应性与突变理论.

With the increases in the breadth and depth of the impacts of climate change, the theories of ecosystem vulnerability, adaptability and catastrophe have gradually been widely applied in the field of ecology to explore and evaluate the sensitivity, vulnerability and adaptation of various ecosystems to climatic change. Based on such research, we can seek better ways to cope with the far-reaching impact of climatic change on ecosystems, and serve the sustainable management of national ecosystems and the construction of ecological security. Although a lot of achievements have been made to distinguish the sensitive regions responding to climatic change and potential tipping points in certain ecosystems, there are still multiple understandings and interpretations of these concepts in the academic community. To some extent, this affects the further development and application of related theories in ecological studies. Therefore, we combed the development history of related concepts, and analyzed the connotation of these concepts from the perspective of ecosystem ecology. Furthermore, we proposed a theoretical framework for ecosystem fragility, adaptability, and catastrophe based on the ecosystem evolution theory and corresponding calculation methods in order to promote the in-depth development of theories of ecosystem fragility, adaptability and catastrophe.

Effects of ecosystem types on the spatial variations in annual gross primary productivity over terrestrial ecosystems of China.

Annual gross primary productivity (AGPP) serves as the basis for forming biomass and carbon sinks. Analysing the effects of ecosystem types on AGPP spatial variations would be beneficial for clarifying the spatial variability in AGPP, which would serve ecological management practices such as ensuring regional food security. Based on published eddy covariance measurements in China, we collected AGPP data from 128 ecosystems and analysed the effects of ecosystem types on the spatial variations in AGPP to reveal the AGPP spatial variability and its influencing factors over terrestrial ecosystems of China. The results showed that AGPP significantly differed among ecosystem types and vegetation regions, with the lowest AGPP appearing in grasslands, while different ecosystem types had comparable AGPP within the same vegetation region. The AGPP of all ecosystem types showed a decreasing latitudinal trend but slight longitudinal and altitudinal trends. Mean annual air temperature (MAT) and mean annual precipitation (MAP) were found to affect the spatial variations in AGPP over most ecosystem types, while other factors played little role. The mean annual leaf area index (LAI) and the maximum leaf area index (MLAI) were also found to affect the spatial variations in AGPP over most ecosystem types. Factors influencing the AGPP spatial variations differed among ecosystem types, but all included climatic and biotic factors. Therefore, climate inducing spatial distribution of ecosystem types and the non-zonal water supply made AGPP values and factors affecting the spatial variations in AGPP differ among ecosystem types, while different ecosystem types within the same vegetation region had comparable AGPP values. The spatial variation in AGPP over terrestrial ecosystems of China resulted from the integrated effects of climatic and biotic factors. Our study provided data support for improving the understanding of global AGPP spatial variability.

[Multi-disciplinary knowledge integration and its technical approaches in the integrated ecology of macroecosystem science]. / å®è§‚ç”Ÿæ€ç³»ç»Ÿç§‘å­¦æ•´åˆç ”ç©¶çš„å¤šå­¦ç§‘çŸ¥è¯†èžåˆåŠå ¶æŠ€æœ¯é€”å¾„.

The development of contemporary macroecosystem sciences requires to comprehensively understand the process mechanism and model mechanism of large-scale macroecosystem structure and function, spatial variation, and dynamic evolution, to realize quantitative simulation, scientific assessment, prediction and early warning of ecosystem change and its impacts on human well-being, and to serve the utilization, protection, regulation, and management of ecosystems. Therefore, a new research field of large-scale integrated ecology of macroecosystem science (IEMES) is emerging. Based on the systematic analysis of the basic theories, approaches and key technologies of integrated ecology of macroecosystem science, the following basic understandings have been formed: 1) IEMES takes macroecosystem at regional, continental, and global scales as the research object, and adopts the methods and technologies of multidisciplinary knowledge integration. It is aimed to solve the major resource and environmental problems during the development of human society, such as food security, resource security, ecological security, and environmental security. 2) The basic scientific and technological tasks of IEMES are to understand the basic structural and functional properties of macroecosystem, monitor the changes of ecosystem state, explain the spatiotemporal evolution of ecosystem, uncover the mechanism of ecosystem operation and maintenance process, quantitatively evaluate the functional state and service capacity of ecosystem, predict the dynamic evolution and geographical pattern of ecosystem, provide early warning of ecosystem changes and ecological environmental disasters. 3) It is needed to reconstruct the theory and methodology system of "multi-source data analysis, multi-model simulation, multi-disciplinary knowledge fusion" and develop key technology of multi-disciplinary knowledge fusion of "multi-scale observation, multi-method verification, multi-process fusion, and cross-scale simulation" for IEMES. 4) The continental scale multi-spatiotemporal ecosystem observation and experiment network is the basic scientific and technological facility to carry out deep integration of multi-disciplinary knowledge. It is necessary to develop key technology of multi-disciplinary ecological knowledge integration of multi-factor, multi-process, multi-interface, multi-medium, multi-scale, and multi-method around the regional, continental, and global scale macroecosystem science issues.

[A process-based model and simulation system of dynamic change and spatial variation in large-scale terrestrial ecosystems]. / 大尺度陆地生态系统动态变化与空间变异的过程模型及模拟系统.

More attention has been paid to the monitoring, assessment, prediction, early warning and sustainable management of regional ecological environment and the changes of ecosystem state in recent years. It is an important scientific and technological task to develop quantitative methods and numerical simulation techniques for ecosystem modelling, and to construct the continental scale numerical simulator with the characteristics of multi-process coupling, multi-technology integration, and multi-objective application for stimulating research on ecosystem and global change and its resources, environment and disaster effects, based on the in-depth understanding of the components, processes, functions, patterns, and their interaction mechanism of terrestrial ecosystem. Here, we reviewed the current status and future direction of terrestrial ecosystem models, and discussed the conceptual framework of developing the simulation system of dynamic change and spatial variation in large-scale terrestrial ecosystems and its resource and environment effect, as well as basic issues on the function orientation and structure design of the simulation system, which would provide reference for constructing Chinese terrestrial ecosystem numerical simulator.

[A coordinated three-dimensional network for observing large-scale terrestrial ecosystem status changes and the consequences on resources and environment]. / å¤§å°ºåº¦é™†åœ°ç”Ÿæ€ç³»ç»ŸçŠ¶æ€å˜åŒ–åŠå ¶èµ„æºçŽ¯å¢ƒæ•ˆåº”çš„ç«‹ä½“åŒ–ååŒè”ç½‘è§‚æµ‹.

Co-driven by environmental change and human activity, global ecosystem has been experiencing rapid changes, with cascading effects on resources and environment. The changes of ecosystem status and its spatiotemporal evolution drivers, and the related resource and environmental effects have been recognized as the long standing topics of large-scale terrestrial ecosystem science. The coordinated observation networks distributed across different continents and the globe provide the valuable tools for observing and evaluating ecosystem state change, for revealing and elaborating mechanisms underlying ecosystem response, for cognizing and understanding ecosystem evolution, and for predicting and early-warning of ecosystem change. Committing to serving the continental-scale ecosystem science and supporting regional ecological environmental governance, this review first comprehensively analyzed the current status of ecological environment observation research networks, then proposed their development directions. This review advocated to develop a collaborative observation system with characteristics of multi-element, multi-interface, multi-medium, multi-process, multi-scale and multi-method, and to establish the new generation of continental ecosystem observation-experiment research network composed of high technology integration, regional distribution network, network management intellectualization, long-term observation & experiment, multi-functional model simulations, and remote data integration and resource sharing. We elaborated on the function orientation, design philosophy, design scheme, construction objectives and technical system of the research network. We hoped provide references for the development of terrestrial ecosystem observation network in China.

Manipulative experiments networks on response and adaptation of terrestrial ecosystems to environmental changes: Building the research methods and technology system.

The feedback relationship between organisms or ecosystems and environment has been a key issue in ecological research. Manipulative experiments with changing biological or environmental factors and large-scale field experiment networks were regarded as effective approaches to understand and accurately quantify the process and mechanisms underlying ecosystem response and adaptation to environmental changes. In recent years, a few networks have been developed, including large-scale networks of field physics simulation experiment (i.e., ECOTRON), ecosystem analysis and experiment platform (AnaEE), international Drought Network, Nutrient Network, and experiment networks based on regional ecological observation stations (i.e., USA-ILTER) at global scale. The development of continent-scale experiment network platform is attracting more attention from the academic community, and will play a more important role in understanding the process and mechanism underlying ecosystem responses to environmental change. We reviewed the development of method and experiment system of ecosystem manipulative experiments, and clearly pointed out that different experiments should form a joint collaborative system to answer fundamental scientific questions about the response and adaptation of ecosystem to global environment change. Manipulative experiments could be classified into four types: 1) Physiological and ecological experiments in closed laboratory equipment; 2) semi-open experiments with changing environmental factors in the field; 3) near-natural field experiments; 4) experiment networks based on field ecological station. Furthermore, we discussed the trends in network design of manipulative experiments focusing on ecosystem response and adaptation to environmental changes and the advantages of large-scale experiments based on natural environmental gradients. We put forward a proposal of integrating the technical advantages of different types of experiments and developing a new generation of field experiment network system. The study discussed the research system based on field experiment network, demonstrated the possibility to understand the patterns and mechanisms of the ecosystem short-term response and long-term adaptation to environmental changes, and proposed some equations to quantify the environmental response of ecosystems. The application of the design plan of the manipulative experiments network proposed here will greatly promote the scientific research level of ecosystems and environmental changes in China and even over the whole world, which has important scientific significance for the national response to climate change and ecological environmental construction.

[Discussion on the multi-disciplinary dimensional basic problems and methodology systems of macroecosystem science research.] / è¯•è®ºå®è§‚ç”Ÿæ€ç³»ç»Ÿç§‘å­¦ç ”ç©¶çš„å¤šå­¦ç§‘ç»´åº¦åŸºæœ¬é—®é¢˜åŠå ¶æ–¹æ³•ä½“ç³».

The urgent requirement of human society to solve major resource and environmental pro-blems at the regional and global scales promotes the rises of macroecosystem science (MES) and the multidisciplinary fusions of natural science and humanities. Furthermore, it facilitates the innovation of macroecosystem scientific theory, as well as the development of continental and global scale knowledge fusion methodology and key technology. With the aim to serve the construction and deve-lopment of continental and global scale knowledge fusion methodological system for the changes of ecosystem status and resource environmental effect studies, we systematically elaborated the multi-disciplinary dimensional basic scientific problems, logic relationships and frontiers in the macroecosystem science, discussed the ideology and content of constructing the continental and global scale research methodological system, proposed to develop the networked observation-networked experiment-numerical simulation-knowledge fusion four-in-one infrastructures. This study would provide theoretical references for the network design of ecosystem observation research in China and at the global scale.

[Technical approach and strategic plan for large-scale ecological and environmental gover-nance and national ecological security pattern construction.] / å¤§å°ºåº¦åŒºåŸŸç”Ÿæ€çŽ¯å¢ƒæ²»ç†åŠå›½å®¶ç”Ÿæ€å®‰å ¨æ ¼å±€æž„å»ºçš„æŠ€æœ¯é€”å¾„å’Œæˆ˜ç•¥å¸ƒå±€.

Terrestrial ecosystems are the core components of the biosphere, supporting human life, production and social and economic activities. With the development of human civilization and the progress of science and technology, the continued expanding resources utilization in terms of scale and intensity has caused environmental problems, including global climate change, biodiversity loss, environmental pollution, resource depletion and ecosystem degradation, which threaten the sustainable development of our society. The public expects ecological research providing scientific theories and systematic solutions for the utilization and protection of ecosystems at the continental and global scale, and the maintenance of sustainable development of human society as well. This study aimed to serve the ecological civilization construction in China, ecological security pattern construction, regional ecological and environmental governance, and the development of macrosystem ecology. We reviewed the effectiveness and experience of regional ecological and environmental governance in China, analyzed the scientific requirements and the characteristics of the times of China's eco-civilization construction towards large-scale ecological research, and proposed using a new philosophy, i.e., nature-based macroecosystem approach, to improve the ecological and environmental governance and ecological security pattern construction at the regional scale. Based on the above-mentioned expounding, we discussed the strategic plan, technical approaches and technological support system of large-scale ecological security pattern construction and ecological and environmental governance in China. This review could provide theoretical references for safe, healthy and beautiful land spatial construction and the progress of eco-civilization of China.

Thinking on large-scale terrestrial ecosystem management and its theoretical fundament and practice.

Ecosystem management at large scales is one of the core solutions to solve current global challenges of environmental and resources problem, mitigate climate change, govern ecosystems and environments regionally and achieve sustainable development. It is also a hotspot in the research and practice of conservation of global natural resources and ecosystems. Based on recalling and synthesizing of several large international actions on ecosystem management in the past two decades, this article rethought the concept of ecosystem management and its application from the perspective of discipline development of ecosystem management, theoretical fundaments and practices. The content included three parts: firstly, we reviewed the development of the scientific concept and practice of ecosystem management, discussed the connotations of the concept and redefined it, and summarized the practice of ecosystem management and its contribution to the development of the discipline. Secondly, we clarified the scientific and technological mission and basic tasks of ecosystem management, organized the discipline system of ecosystem management and its main research fields, summarized fundamental theories and the knowledge system of the science of ecosystem management, and clarified critical steps of ecosystem management actions, basic elements of management plans and management approaches. Finally, we proposed new trends of scientific research and the discipline development of ecosystem management, discussed the important spatial scales and its objects system of the scientific research on ecosystem management, proposed the cutting-edge scientific questions of global ecosystem management, integrative ecology thought and macro ecosystem approach. This review aimed at providing references for the scientific research and discipline deve-lopment of ecosystem management in China.

Discussion on the theoretical basis and technical system of large-scale terrestrial ecosystem science research.

Large-scale terrestrial ecosystem science research becomes an important research field with the promotion of meeting the scientific demand of biodiversity conservation, global climate change mitigation, regional eco-environment governance, and social sustainable development. It is developing rapidly under the guidance of China's ecological civilization construction strategy. Here, we systematically discussed the missions, theoretical foundation and methodology of large-scale terrestrial ecosystem science research and proposed a new theoretical foundation, conceptual system and logical framework for macroecosystem science research on the basis of macrosystem ecology theory. It elaborated the discipline connotation and application of the macroecosystem science to 1) deve-lop the conceptual network of ecosystem science based on the systematic characteristics of ecosystems; 2) develop the theoretical system of ecosystem state change analysis based on the ecosystem integrity and emergence characteristics; 3) develop the theoretical system of integrated research for ecosystem structure-process-function-service cascade relationship based on the attributes and state of ecosystems. We also discussed the methodology and technical system of regional and continental macroecosystem science research, and highlighted the urgency to construct a new generation of continental ecosystem observation and research network, and to develop the network observation-network experiment-numerical simulation-knowledge fusion four-in-one infrastructures.

[Discussion on the scientific concept of ecology and its evolution and the contemporary ecologi-cal discipline system]. / ç”Ÿæ€å­¦çš„ç§‘å­¦æ¦‚å¿µåŠå ¶æ¼”å˜ä¸Žå½“ä»£ç”Ÿæ€å­¦å­¦ç§‘ä½“ç³»ä¹‹å•†æ¦·.

Ecology is not only a branch of biology, but also an important part of environmental science and earth system science. The results of ecological studies can be directly applied in biodiversity conservation of plant, animal and microbe, biological resource utilization and biological industry management, and other fields. The concept of ecosystem extends classic ecology or basic ecology research to a new stage of ecosystem ecology or ecosystem science, which has laid a theoretical foundation for the scientific research of ecological environment at the global and continental scales, and has promoted the integration of biology, geography, and environmental science, and cross disciplinary of the natural sciences, humanities, and social economic sciences. During the integration processes, together with constantly absorbing nutrition from different disciplines, researches of eco-logy put forward a lot of scientific concepts or theories, and have been applied and developed in the relevant scientific research, formed contemporary ecology and ecosystem science system centered on the cognition of ecosystem, resource environment, and the mutual feedback relation with human society. We comprehensively discussed the scientific concept, basic theory, and discipline system of contemporary ecology from the origin and development of ecological thought, the scientific connotation, and extension of ecological concept, etc., and tried to sort out, investigate, and analyze the scientific connotation, discipline category and discipline system of contemporary ecology, put forward the branch discipline system classification scheme of basic ecology and applied ecology, with the aim to provide references for perfecting and reconstructing the discipline system of contemporary ecology.

[Regulation effects of temperate broadleaved Korean pine forest on temperature and humidity in Changbai Mountain, China.] / 长白山温带阔叶红松林对温湿环境的调节效应.

Forests can improve climate and regulate micro-environment. The study of forest micro-climate is of great significance to reveal forest ecosystem function and evaluate the benefits of forest ecological environment. With broadleaved Korean pine forest in Changbai Mountain as test material, the diurnal and seasonal variations of the mean, maximum and minimum temperature, relative humidity and surface soil temperature were analyzed based on the meteorological data of flux tower in the forest and nearby meteorological station in the open land from 2003 to 2014. The results showed that air temperature and relative humidity in the forest showed a unimodal U-shaped diurnal pattern, respectively. The diurnal range was 2.31 ℃ and 8.3% lower than that of the open land. The diurnal surface soil temperature tended to be a constant, indicating an alleviating effects of broadleaved Korean pine forest on the diurnal variation of temperature and moisture. The cooling effect was mainly observed in summer, while the warming effect was significant in winter. The air and soil temperatures in forest in summer were 1.30 and 3.91 ℃ lower than those in the open land, and were 2.06 and 5.44 ℃ higher than those in the open land in winter. Forest regulated the maximum and minimum temperatures significantly. On the season scale, the maximum air and soil temperature in forest decreased by 1.80 and 5.45 ℃ in summer, while the minimum air and soil temperature increased by 3.69 and 7.92 ℃ in winter. On the annual scale, the maximum air and soil temperature in forest were 1.60 and 4.99 ℃ lower than those in the open land, and the minimum air and soil temperature were 1.12 and 8.82 ℃ higher than those in the open land, respectively. The regulating effects of forests on soil temperature was stronger than that on air temperature. Forests mainly warmed the air and soil temperature at cold condition.