WANG Bing 1 , JIN Fang 2 , YANG Fengwei 2 , CUI Xianghui 1
The Chinese Forest Ecosystem Research Network (CFERN), established in late 1950's and directly constructed and administered by the Science and Technology Department of State Forestry Administration of China, is a large ecology research network that focuses on long-term ecosystem locating-observation. It embodies 15 sites that represent diverse ecosystems and research emphases, including 6 state-level sites. The Network covers all climate zones of China, having intersecting ecological gradient network driven by heat from south to north and by moisture from east to west. CFERN Programme Management center coordinates communication, network publications, and research-planning activities.
As an important, internationally used method of studying and unveiling the structure of an ecosystem and its functional changing laws, long-term locating-observation is an irreplaceable research methodology of establishing ecosystem observation sites on typically natural or manual ecosystem-regions, in long term observing in a fixed place the dynamic changing patterns and processes of the ecosystems' constitution, structure, bio-productivity, nutrients cycling, water cycling, and energy utilization, etc. under the interference of natural conditions and/or some contrived activities, illustrating an ecosystem's intrinsic mechanisms of its occurrence, development, and succession, and its homeostasis, as well as its participation in the process of bio-geochemistry circulation, etc. Ever since the UN Human and Environment Conference in 1972 and the UN Environment and Development 1992 Conference, many countries have established in succession various kinds of ecosystem place-research and observation networks. Among them the most famous worldwide are International Global Biosphere Plan (IGBP), Long-Term Ecology Research (LTER) based in the US, Environmental Change Network (ECN) based in the UK. As to the basic information of forest resources, the UN Food and Agricultural Organization (FAO) established a comprehensive Database Management System (DBMS) for the forest resources all over the world, with the aim of evaluating the status quo of world's forest resources and its dynamic changing laws. This DBMS assembles the forest resource data from more than 100 countries and regions around the world, both in and out the T-Zone, and provides data inquiry and quantitative evaluation by adopting FORIS and Geographical Information System (GIS) technology.
Based on the needs of China's environment, in order to accommodate to the spanning trend of forestry development in the new century, the Chinese Forest Ecosystem Research Network (CFERN) has been established and gradually developed to meet the requirements of China's Six Key Forestry Projects, including natural forest protection, sand-control projects, crop-field-back-to-forest projects, and so on. The primary goal of CFERN is, through long-term, timing place-observation by the field sites, to 1) taking moisture cycling and biogeochemical cycling as a starting point, systematically analyze the physical, chemical and biological processes of the different ecosystems' (forests, everglade, desert, mountainous areas) impact on the environment; 2) from a pattern-process-scale point of view, study the laws of material transformation and energy balance in surface of water, soil, atmosphere, creature, quantitatively analyzing succession of ecological process, system of transformation and coupling in different spatial-temporal scales; 3) establish a system of evaluation, prediction and alarm, regulation and control of forest environment and its benefits.
The Network's Research and Administration Center, located in the Dagangshan Forest Ecosystem Research Station in Jiangxi Province and directly administered by the Science and Technology Department of the State Forestry Administration, is a daily administrative institution of CFERN. It is established to organize and coordinate the observation projects and research tasks of the ecological stations within the Network, to construct databases of the stations' observations, research achievements and information and data gathered from other channels, and, through synthesizing and analyzing those data, to research, predict and forecast the status quo and dynamics of forest ecosystem, resources and environment at regional and above levels. By doing so, the Center will be able to provide scientific basis for the decision-making sections at all levels, to ultimately serve the eco-environmental construction and sustainable development of resources in China.
1.2.1 Overall Objectives of Network Research
Based on long-term place-observations of intersecting networks, the structure and functions of China's forest ecosystem would be synchronously monitored perennially and comprehensively at the four levels of individual, population, community and system; the correlationship between the composition and structure of forest ecosystem and climatic environment would be revealed; the impacts of human activities on ecosystem and ego-regulating process would be monitored and surveyed; the functions and position of forest in eco-environment construction would be determined; and, a dynamic system of forest eco-environment evaluation, monitoring, forecasting and alarming would be set up. All of the above will provide scientific bases for the construction of Chinese and global eco-environment as well as for the sustainable utilization of forest resources and sustainable development of economy.
1.2.2 Main Tasks of Network Research
Through locating research, making the best of the advanced modern ground and spatial observation technologies, introducing coupled research method of ecological gradients, to study the structure, functional laws and feedback mechanism of Chinese forest ecosystem, as well as its effects on China's social and economic development (RS, GPS, GIS). The main tasks of CFERN are: (1) active construction of the database on the structure and functions of Chinese forest ecosystem and its ecological environmental factors; (2) the database construction of forest resources, ecological environment, water resources and related social economy in both regional and national scales; (3) the establishment of an evaluation system of forest ecological effects in China's main drainage areas; (4) the establishment of a forest eco-environment monitoring network and a dynamic prediction and alarm system.
Stations selected are from northern Daxing'an Mountains to southern Hainan Island, and from eastern Xiaoxing'an Mountains to western Xinjiang Tianshan Mountains and Qinghai-Tibet Plateau. It comprises the most integrate and continuous geographical zones of vegetation and soil, from frigid temperate zones to tropical zones, from humid regions to extremely droughty areas. It is also the most representative latitude-longitude belt system driven by energy and water, and it can reflect the change laws of forest vegetation gradients driven by temperature and moisture. Thus the Network can observe and monitor the change and process of forest ecosystem in China's main drainage areas, such as the Long River, the Yellow River, the Heilongjiang River, etc., and analyze the ecological benefits of forest on industry and agriculture.
Chart 1 CFERN Stations Distribution
Compared with that in some developed countries, placed-forest-ecosystem-research in China is at an age quite young. In late 1950's, a group of scientists, using theories and methods of researching biogeocenose developed in the former Soviet Union for reference, carried out several semi-locating research. Since 1970, material and energy flow locating research was started by extensively absorbing ecosystem theories and monitoring means developed in Europe and America, and forestry ecosystem management ideology and practical models were gradually established with the aim of multi-level energy utilization and low energy consumption with high effects. In 1978, the Forestry Ministry of China (now the State Forestry Administration) formally established the Forestry Ecosystem Research Planning Conference and constituted a nationwide development planning protocol.
In late 1980's，the scale of forest ecosystem research station continuously improved and enlarged, and developed towards network. Meanwhile, through the seventh 5-year, the eighth 5-year and the ninth 5-year national scientific and technological brainstorm programmes and forestry ecological engineer construction projects, the forestry sectors established about 30 monitoring sites at the Three North, Long River, Huanghe River, coastal areas, Taihangshan regions and other forestry ecological engineer areas, in order to monitor ecological functions and environmental effects of shelter forest system. In addition, the forestry sectors set up many ecological monitoring sites at desertification areas, important wetlands and Three Gorges to systematically observe the atmosphere, vegetation, soil and hydrology and so on. These monitoring sites of different types constituted the subject of Chinese forestry eco-environment monitoring network and formed an ecological monitoring network system from coastal regions to inland regions, from forest network at farmlands to forests on mountains and from inland wetlands to desertification areas in arid area. These forestry eco-environment monitoring systems obtained long-term monitoring data and information at different levels and a series of results, which played an important role in Chinese forestry eco-environment construction. Nowadays, however, Chinese forestry eco-environment monitoring network construction can not meet the demands of Chinese forestry eco-environmental construction yet because of the lack of reasonable spatial distribution, normalized and united monitoring technology system as well as modern and automatic observation facilities.
According to the requirements and developmental tendency of China's eco-environment construction, the Chinese Forestry Ministry, in 1992, held a working conference concerned with 11 existing forest ecosystem stations. At the conference, research results of ten years were all-round concluded, planning was revised, and network and experts panel were established. The conference was concerned with international network research and integration of global environment and development strategy, made Chinese forest ecosystem research enter a new stage. Afterwards, Chinese Forest Ecosystem Research Network (CFERN) was established, consisting of 11 forest system stations, and CFERN Planning revised in 1992,was lay down. Xinjiang Tianshan station, Fujian Wuyishan station were added in the network in 1998, and Henan Baotianman station as well as Guizhou Kaiyang station were also added in the network in 2000. So far, CFERN almost covers whole China with ecological gradient across network driven by heat from north to south and by water from east to west.
At present, CFERN possesses favorable development environment and opportunities and initially formed reasonable distribution along different climatic belts. The belts cover the most complete and continuous vegetation and soil belt series from frigid temperate zone to tropical zone, from moist regions to extremely arid regions. So, CFERN is the most typical latitude and longitude belt system driven by heat and water, fundamentally reflecting forest vegetation gradient changing laws driven by heat and water. In the network, the straight distances between the most southern station and the most northern station or between the most eastern station and the most western station exceeds 3700km, which fit in with the policy scale of national eco-environmental construction and thus can monitor changes and effects of forest ecosystem at Long River, Huanghe River, Yaluzangbujiang River, Songhuajiang River, and analyze forests position and functions in Chinese ecological construction.
By 2000, 6 stations of CFERN, including Jianfengling station, Dagangshan station, Qilianshan station, Maoershan station, Huitong station and Huoditang station, had been ranked as state-level key field stations, which could get specialized funds from the State Ministry of Science and Technology. Some ecological stations of China Ecosystem Research (CERN) and Dagangshan station and Jianfengling station of CFERN are ranked among the 818 TEMs of GTOS Network constructed by FAO, which shows that the research level of these ecological stations are primarily recognized both in domestic and abroad.
Facing the challenge of the spanning trend of forestry development in the 21 st century, CFERN's key research tasks in the next 5 years should be: making the best of the advanced modern ground and spatial observation technologies, introducing coupled research method of ecological gradient, to study the structure, functional laws and feedback mechanism of China's ecosystem, as well as its effects on China's social and economic development; based on the independent prophase research by each station, through the construction of CFERN Research Center and its operation as an entity, boosting observations of ecosystems and the research of variational trends of ecological environment in large and medium scales all over China, to provide cogent groundwork to resolve hotspot problems such as carbon excretion and water resource shortage. In the next 5 years the foci of CFERN's research are: 1) active construction of the database and homepage to share information on the structure and functions of China's forest ecosystem and its ecological environment factors through the establishment of CFERN Research Center; 2) setting up a coupled simulation model of forest resources, ecological environment, water resources, carbon cycling and correlative social economic data in both regional and national scales; 3) the establishment of an evaluation system of forest ecological effects in China's main drainage areas (such as the Long River, the Yellow River, etc.) and typical eco-environmental-fragile regions; 4) the establishment of a forest eco-environment monitoring network constitutes 15 ecological stations and a dynamic prediction and alarm system.
To accomplish the research tasks mentioned above, it is a must to amend the monomial models of ecological factors established at the prophase with new data obtained from observations and experimentations by the different stations, and to synthesize them in two approaches. The first approach is coupling the eco-environmental changes and the units-correlation of forest ecosystems in different unit types and different CO2-temperature-moisture correlation types, e.g., the coupling of dynamic models of forest communities, functional models of ecosystems, variational models of soil water and environmental-change correlation, the coupling of vegetation structure and the process of ecosystems, etc., as well as constructing a synthesized atmosphere-soil-vegetation model in terms of its response to global changes. The second approach is the small-to-large scale-transition of mono-factored forest ecological models, including solving new problems that will probably arise with the increase by degrees, setting up the regional-scaled model of moisture and CO2, and scale-transiting towards national scales. Individual-patch-landscape-scale coupled-ecosystem-structural-modeling is to set up coupled models in multidimensional spatio-temporal scales based on ecological process. It requests, in small scales, to reflect the impact of temperature, moisture, and CO2-concentration changes on the physiological and ecological vegetal process and, in large scales, focuses on the dynamic model of global vegetation based on physiological mechanism. As to research methods, model-nesting technology, GIS (Geographical Information System) technology, and remote sensing techniques should be adopted to spatially transform and expand the models.
At present, according to the international situation of the ecological domain and the construction needs of national ecological environment, CFERN urgently needs to in the near future initiate research on the relationship between forest and water, and on the impacts of forest on carbon cycling.
CFERN will, through collaborative experimentations by the ecological stations within the network, research on the impacts of ecological environment and its regulating mechanisms along the large drainage areas of the upper reaches of the Long River and the upper and middle reaches of the Yellow River, establish an integration mechanism and deductive model of the ecological and hydrological processes in different scales, illustrate the influence of forest vegetation's spatio-temporal changes on the quantity and quality of water resources, and their influence on soil erosion and water conservation functions in different spatio-temporal scales. Meanwhile, CFERN will make efforts to obtain break-through research development and innovations on these aspects: establishment of changing laws and integration methods of simulation models of material and energy transportation of soil-forest vegetation-atmosphere continuum in different scales; scale-transition techniques of the ecological processes and hydrological processes of forest vegetation; regulation and control theories of ecosystems' service functions such as using forest vegetation to maintain water stability and to avoid flooding; and, theories on vegetation ecological environment construction. CFERN will then establish and develop the system info of forest hydrology and drainage-area-hydrological-management in different scales, to provide theoretical and critical basis for the security of regional soil and ecological environment of the upper reaches of the Long River and the upper and middle reaches of Yellow River, for the improvement of agro-ecological environment, and for successful executions of natural forest protection projects and crop-field-back-to-forest projects.
Based on the 15 ecosystem stations, taking advantage of data and information of forest resources in existence, CFERN will try to find a research framework which be fit for evaluating the effects of Chinese forest in regulating atmosphere CO2 balance.
The research framework for estimating carbon storage of Chinese forest and its change should be: with the ecological stations as base point，the forest carbon storage and its change would be determined exactly，and researched in-depth and particularly, including biomass survey and Stat. of representative forest type, sensibility analysis of disturbance factors，estimate and survey of carbon stable isotope storage and turnover of forest product, forest biomass and forest soil, and so on.
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1. Research Institute of Forest Ecology, Environment and Protection, Chinese Academy of Forestry, Beijing, China 100091
2. Science and Technology Department of State Forestry Administration, Beijing, China 100714
Add: 100091, Chinese Academy of Forestry 67#, Haidian district, Beijing, P.R.China.
E-mail: [email protected].
Add: 100714, No.18 Hepingli Dongjie, Beijing, P.R.China.
E-mail: [email protected]
Add: 100714, No.18 Hepingli Dongjie, Beijing, P.R.China.
E-mail: [email protected].
Add: 100091, Chinese Academy of Forestry 67#, Haidian district, Beijing, P.R.China.
E-mail: [email protected].