Spatial Variability and Seasonal Change of Radioactive Caesium Concentration in Grassland Vegetation

The damage from the Fukushima Daiichi Nuclear Power Plant caused by the Great East Japan Earthquake and tsunami on March 11, 2011 resulted in serious radioactive pollution over Eastern Japan. The distribution of radioactive fallout was largely determined by wind and rainfall patterns in March 2011. Distribution patterns were not necessarily in accordance with the distance from the nuclear power plant. In Iwate Prefecture (160 to 340 km north of the nuclear power plant), the amount of fallout of radioactive material in the southern region was greater than in the northern, but the distribution pattern was complex (Fig. 1, Tsuiki and Maeda 2012a; 2012b). In the southern region, the radioactive caesium (Cs) concentrations of herbage plants exceeded the provisional safety standard for dairy and fattening cattle feed, and the livestock industry has been seriously affected in numerous ways e.g. needing to dispose of polluted forage, grazing prohibitions, declines in beef prices, suspension of vending, and blanket testing of beef cattle. In this study, the spatial variability of radioactive Cs concentration in soil and vegetation was evaluated on grasslands in 2012

Plant tissues suitable for individual selection of Mg in tall fescue

Energy dispersive x-ray microanalyzer (EDX) is an efficient apparatus for forage screening. It can evaluate only a small amount of sample at a time. On the other hand, for screening forage mineral concentrations it requires that the sample is a representative of the whole plant for mineral concentrations. This study was conducted to identify the suitable tissue in selecting tall fescue populations for high Mg concentration by using MX

Mineral uptake of high-Mg cultivars of Italian ryegrass and tall fescue grown under different level of potassium

Magnesium and potassium interactions affect the concentration of Mg in forages. By evaluating the performance of high-Mg cultivars under different nutrient levels it is possible to understand interrelationship, of nutrients as well as to find out optimum K levet for screening forage plants. For this purpose. Italian ryegrass and tall fescue eultivars were studied using nutrient solution culture to evaluate the growth and mineral uptake under different K levels

Modeling of the Fukushima Daiichi Nuclear Power Plant Derived Radioactive Cesium Dynamics in Grazing Grassland

The damage to the Fukushima Daiichi Nuclear Power Plant incurred following the Great East Japan Earthquake and tsunami on March 11, 2011 resulted in serious radioactive pollution of Eastern Japan. In some grasslands of this area, radioactive cesium (Cs) content of grasses exceeded the provisional safety standard for use as feed for dairy and beef cattle of 100 Bq kg–1 fresh weight, and the livestock industry has been seriously affected in numerous ways: needing to dispose of polluted forage, grazing prohibitions, declines in beef prices, suspensions of shipping beef to market, and blanket testing of beef cattle (Manabe et al., 2013). The spatial distribution of radioactive Cs in grasslands was complex in various scales (Tsuiki and Maeda, 2012a; 2012b). So it is difficult to estimate actual pollution level in grassland ecosystems. The transfer of radioactive Cs from soil to plant is affected by soil soluble potassium (K) concentration, pH, clay and organic matter contents (Absalom et al., 2001; Tsuiki et al., 2013). The radioactive Cs dynamics in soil-plantanimal system is complex and modeling is necessary to clarify the relationships. In this study, a model of radioactive Cs dynamics in Zoysia japonica Steud. dominated grazing grassland was developed to predict radioactive Cs concentration of grass and grazing cattle

Integrated Evaluation of Soil Carbon Budget by Manure Application on Forage Production

Grasslands and forage crop fields produce forages and also have many services and functions such as repositories of biodiversity, climate regulation and soil conservation (Sala and Paruelo, 1997). Carbon budget is one of these important ecosystem services by high levels of carbon sequestration below ground (Hungate et al., 1997). Manure application increases carbon budget and also affects forage production, NO3- leaching to underground water and N2O emission to atmosphere. Integrated evaluation of these various environmental impacts is important to find optimum condition for forage production and environmental impacts. LIME2 (Life-cycle Impact assessment Method based on Endpoint modeling 2, Itsubo and Inaba, 2010) is one of the methods to evaluate environmental impacts and to integrate them into a single index of environmental damages with the unit of Japanese yen. By comparing this index to economic benefit of forage production, integrated evaluation of environmental damages and profit of farmers is achieved. In this study, the effects of manure application to forage production, carbon budget, NO3- leaching and N2O emission were evaluated and optimum level of manure application level was estimated with LIME2 integration factors