Controlling Fates of Pollutants Related to the High Technology Industries in Agro-Ecosystems
(Research Period : 1993-1997)
Recently, the so-called high technology industries (HTI) have expanded their activities into rural areas seeking clean air and water. There will be much higher potential than ever before for the HTI waste contamination of agro-environments, and then a variety of agricultural products. It is, therefore, urgently needed to develop reliable and sophisticated technology for preventing HTI waste pollution. A project to cope with the HTI waste pollution was started in 1993 and completed in 1997. The results obtained were as follows :
1)Dynamics of rare metals in the soil-water interface : Two promising countermeasures were proposed to prevent water/soil contamination by rare metals, (1) keep soil-water systems in the neutral pH range, (2) apply calcareous materials to minimize the SS formation.
2)Chemical forms and behavior of rare metals in soils : The rare metal uptake by Bassica campestris could be minimized in terms of a neutral soil pH. Soil Mn antagonistically decreased the plant uptake of Cd in an andosol, and Mo, Rb, and Co in alluvial soils.
3)Chemical forms of 36 rare metals contained in 22 kinds of sludge for wastewater treatment were analyzed to examine the mobility and bioavailability of these metals. The rare metal content in sludge-amended soils are managed by monitoring the levels of Zn, Cd, Ni, As and Tl.
4)More than 200 plant species were analyzed to survey the plants which accumulated specific rare metals inside the tissues. Cd, Cs, Tl, were accumulated in Compositae family, Saxifragaceae, Polygonaceae, respectively and Pteridophyte accumulated Sb, Pb, La, Tl and Bi. Broadleaf dock, red top and tall fescue were estimated to decrease soil Tl concentration by 50% at 3.5, 7.2 and 9.2 years, respectively after each vegetation was established.

Development of Techniques for Predicting Cool-Weather Damage Through the Analysis of Climate, Crops, and Soil
(Research period : 1994-1997)
Twenty major research achievements were published in a color book in February 1998. In addition, a new crop simulation model was developed based on a real time analysis and prediction system newly assembled for the daily crop growth and crop yields.
A training workshop was held for concerned scientists in February 27, 1998, to familiarize them with using the simulation model, including data collection from crop fields, meteorological data use, and prediction of the growth and yield of rice, corn and soybean crops. A training manual and the simulation results were published for the users' convenience.

A New Stage of Environmental Monitoring in Rural Area
(Research Period : 1994-1998)
Recently, environmental and agricultural scientists warn that the ground and surface water in rural areas may be polluted by N and P drained out of agricultural lands. This results in the aggravation of rural water environments and decreased bio-diverity, and then affects human health. However, farmers and residents in rural areas have not paid much attention to such pollution mainly due to (1) lack of information regarding adverse effects of agricultural practices on the rural environment, (2) difficulty in determining non-point sources of pollutants. It is, therefore, urgently needed to develop efficient and reliable environmental monitoring techniques. Nine speakers proposed new and sophisticated methods to quantify the amounts of N and P leached out of the agricultural lands, evaluate the contribution of non-point sources to the river-water quality, and monitor the quality of surface and ground-water in small catchments. A total of 324 scientists took part in this workshop and earnestly discussed new proposals.

Studies on Evaluation, Prediction and Modeling of Carbon Dioxide Dynamics in Terrestrial Ecosystem
(Research Period : 1996-1998)
The expected results of this project are as follows : (1) model development for predicting CO₂ variation in natural and artificial ecosystems, such as jack pine boreal forest, tropical monsoon forest, and double-cropped rotation systems and so forth, (2) develoment of models concerning soil microbiological functions, and (3) development of global carbon cycling models for the evaluation and prediction of carbon dynamics in terrestrial ecosystems.

Safety Assessment for Application of Recombinant DNA Technology in Agriculture
(Research period : 1996-1998)
The project is to develop the safety assessmnt methodology for the application of recombinant DNA techniques in agriculture.
Transgenic rice plants were assessed for their safety as a food in terms of allergenicity and nutritious elements. Transgenic trees were found to be genetically stable. A suicide gene system was constucted for microbes. A killer yeast defective in catabolizing lactic acid was assessed for its use and safety. Vaccinia viruses transformed with cow leukemia virus gene was assessed for the effectiveness as a live vaccine. Recombination of a plant virus was assayed to evaluate possible recombination of transgenic viruses with other viruses. Information on the use of recombinant DNA techniques and their safety were collected and public acceptance of the recombinant DNA technologies was surveyed.

Development of Bioremediation Techniques through the Employment and Reinforcement of Microbial - Remediation Ability
(Research Period: 1996-1999)
Various pollutants, including recalcitrant chemicals, pose serious environmental problems. The bioremediation technique proved to be promising for its cost effectiveness, efficient decomposition and removal of pollutants, and safety to the environment.
The objectives of this project are : (1) isolation, screening and characterization of promising microorganisms for organic pollutant degradation, (2) evalution of degrading gene stability during cultivation and in the environment, (3) analysis of structures, functions, and expression of degrading genes, and improvement in their degrading ability, (4) analysis of bioremediation ability exerted by mixed cultures in the environment, and technology development to optimize the degrading ability of microorganisms.

Comprehensive Evalution of the Implications of Agriculture, Forestry, and Fisheries, and the Trade of their Products, on Natural Resources and the Environment
(Research period : 1996-2000)
The purpose of this project is to develop macro-indicators (MI) for flood prevention, water retention, water quality, soil erosion, landslide susceptibility, soil fertility, biodiversity, climatic mitigation, and landscape, and to evaluate the impacts of agriculture, forestry and fisheries on natural resources and the environment. A research meeting was held on 2-3 March 1997 at NIAES with about 140 scientists. To promptly cope with environmental issuse inside and outside Japan, many proposed macro-indicators were evaluated, and 12 principal indicators were selected.

Experiment and Modeling of Rice Ecosystems under High Atmospheric CO₂
(Research Period : 1996-2000)
The newly designed FACE (Free-Air CO₂ Enrichment) system possesses several innovative features such as light and simple FACE rings used to deliver the pure-CO₂. Using the new system, the experiment was started to evaluate the effect of enriched CO₂ on the growth and yield of rice. Changes in carbon and nitrogen dynamics and methane emission are also traced in the rice ecosystem under the artificially increased CO₂ concentration.

back to Contents

back to NIAES Home Page