Agriculture is playing increasingly important roles in maintaining and strengthening the environment. Japanese agriculture has contributed to land and environmental conservation through the ecological functions of the agro-ecosystems. The functions are, however, being threatened by the deterioration of environmental resources accompanying the diversion of agricultural lands to other purposes in urban areas, by the abandonment of cultivated lands in hilly and mountainous areas, by the intensification of agriculture, and by global climate changes. To cope with these problems, NIAES has four main research objectives:

1. Developing methods for classifying and evaluating characteristics of agro-environmental resources
   In order to establish sustainable agriculture in harmony with the environmental conservation and food production security it is necessary to make proper use of each resource in the agro-ecosystem and improve its functions with the global perspective Therefore we are going to engage in the following research themes with heed to social needs; 1) to develop methods to classify elements of the agro environment 2) to research the properties of climate, soil and water resources and other biological resources and to evaluate their functions, and 3) to research the properties of agricultural supplies and evaluate their functions. (Fig.1)
2. Mechanisms, functions, and control of the matter-energy cycle and interrelations among biological and physical components in agroecosystems
   In order to sustain and upgrade agricultural production it is necessary to elucidate the interactive mechanisms and functions among biological and physical components of agro-ecosystems, and to establish integrated technologies for environmentally sound agriculture From the above mentioned viewpoints multiple studies on the role and dynamics of vegetation insects microorganisms and their interactions in agroecosystems are being carried out The measures for evaluating the safety of farm chemicals and decreasing their impact on the environment are being developed. (Fig.2)
3. Analysis and evaluation of agroecological funtions on the preservation of global environment, and development of techniques for decreasing negative effects of agriculture on the global environment
   In order to resolve the global issue of environmental changes, it is necessary to clarify the relationships between the global environment and agro-ecosystem and also to develop the techniques for mitigating the impacts of agriculture on the global environmental issues. Two research objectives were planned and now are being carried out as follows: 1) analysis and evaluation of effects of global environmental change on the agro-ecosystem and 2) analysis and evaluation of impacts of the agro-ecosystem on the global environment and development of the techniques for mitigating the impacts of agriculture on the global environment. (Fig.3)
4. Development of comprehensive planning and management techniques of the agro-ecosystem
   For the development of agriculture and rural districts on a long term basis it is necessary to develop sustainable agriculture in harmony with the ecosystem to increase amenities in rural districts and to conserve a desirable natural environment Furthermore it is also necessary to develop the comprehensive management of rural districts based on knowledge of the structure and functions of the agro-ecosystem.Therefore we carry out the following studies: 1) development systems to collect analyze process, and utilize data on the agro ecosystem, 2) comprehensively evaluate the to the structure, function, and development of methods to predict variation in the agro-ecosystem, 3) develop techniques to control and optimize the material cycle between inside and outside the agro-ecosystem, 4) develop comprehensive planning methods and management systems for agro-ecosystems to sustain and increase the positive effects of agriculture and rural districts as well as to establish sustainable and stable production within the agro-environment. (Fig.4)

Fig.1 Micrometeorogical measurement over dune and grassland at Naiman, in Inner Mongoria, China.

Fig.2 A larva of Epilachna Vigintipunctata and its damage caused on a leaf of Solanum carolinense.

Fig.3 Autmated chamber for measuring CH₄ emission from rice paddy fields.
 

Fig.4 Spatial distribution of the critical loads estimates of acid rain.