We have developed a quick and simple method of determining major and trace-element concentrations in farmyard manure using an energy dispersive X-ray fluorescence spectrometer (EDXRF) employing Cartesian geometry and equipped with secondary targets. A total of 122 farmyard manure samples (75 cattle manure, 23 poultry manure, 24 swine manure) were used to obtain calibration curves for 24 elements (P, K, Ca, Mg, Fe, Cu, Zn, Mn, Mo, Pb, Cd, As, Na, Al, Ti, V, Rb, Sr, Ba, Ce, Cr, Co, Ni and Zr). A sample briquette obtained by applying pressure to manure powder packed into a plastic ring was used for the fluorescence X-ray analysis, and calibration curves showing good linearity for 20 of the elements (all except Cr, Co, Ni and Zr) were obtained. The values determined using EDXRF showed close agreement with those determined using ICP-AES/MS. These results indicated that the XRF technique is suitable for practical analysis of major and trace-element concentrations in farmyard manure. The time needed to measure five elements (P, K, Ca, Cu, Zn) was thirty minutes per sample, and it also appears possible to reduce the measurement time if the precision requested by the user is lower. Determination of nutrients and hazardous heavy metals in farmyard manure prior to its application can be a useful technique to avoid excess accumulation of these elements on farmland.

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We estimated the quantities of fresh and composted livestock excreta, food refuse, and sewage sludge on a national and prefectural scale in Japan in 2005. The total amount of livestock excreta produced was__Tg fresh weight (FW), which contained 680Gg N and 116Gg P. The amount of compost produced from it was 11.9Tg FW, which contained 184Gg N; that is, composting reduced the N content to less than one-third. The total amount of food refuse produced was 22 Tg FW, which contained 185Gg N and 26Gg P. The amount of compost produced from it was 5.8Tg FW, which contained 79Gg N; that is, composting reduced the N content to less than half. The total amount of sewage sludge produced was 75Tg FW, which contained 106Gg N and 20Gg P. The amount of compost produced from it was 2.0Tg FW (1/40), which contained 40Gg N; that is, composting reduced the N content to 2/5. Thus, composting is effective at reducing the amount of refuse. Japanese farmland has the capacity to receive 40Tg FW of composted cattle manure: at 0 to 5.62Mg FW ha^<-1> to paddy fields (depending on the prefecture), 10Mg FW ha^<-1> to upland fields, 7.5Mg FW ha^<-1> to orchards, and 20Mg FW ha^<-1> to forage fields. The quantities of composted livestock manure, food refuse, and sewage sludge equated to 17, 15, and 5Tg cattle manure. Therefore, Japanese farmland has the capacity to receive all composted wastes produced nationally. However, the amounts produced and the capacities to use them vary widely among prefectures. By our estimation, 6 prefectures out of 47 cannot use all the composted manure produced within them, and 14 can receive composts from outside. Our estimation did not take into account any limitations on nutrients in excess of needs or the heavy metal load. Therefore, nutrient imbalances might occur. The amount of compost made from organic wastes and the capacity of farmland to use it could be used to decide the fate of the wastes.

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On the grounds that salt-concentrated compost is a valuable organic fertilizer, we investigated the effects of successive applications on the growth of komatsuna (Brassica rapa var. peruviridis) and on soil by investigating the time course transition of the soil solution composition and its cation balance, and crop yield. In the first pot experiment, komatsuna was grown 4 times in succession in an Andosol and a Brown Lowland soil (Fluvisol) with chemical fertilizer, ordinary compost, or salt-concentrated compost. Although aboveground dry-matter yields with salt-concentrated compost tended to be higher than those with ordinary compost from the first to the third crop on both soils, they were significantly lower in the fourth crop. As the amount of salt-concentrated compost increased, the concentrations of Ca and Mg in komatsuna decreased. Soil electrical conductivity increased with the amount and number of applications of salt-concentrated compost. The values of AR^<K+Na>, which were used to estimate the cation composition of the soil solution, decreased to a steady level by the beginning of the third crop. The results suggest that the yield decline caused by repeated application of salt-concentrated compost was due to both an increased soil solution concentration and its unsuitable composition, which prevented the komatsuna from absorbing Ca and Mg from the soil solution. In the second pot experiment, in which komatsuna was grown in the Andosol with salt-concentrated compost applied at 10 or 20Mg ha^<-1>, co-application of dolomite at 5Mg ha^<-1> improved the soil solution AR^<K+Na> immediately, and the yield of komatsuna increased accordingly.

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We examined the effects of the stage of maturity of cattle manure compost and the timing of application on the N-fertilizer effect in forage rice. Rice plants were grown in several plots to which cattle manure compost of different stages of maturity was applied 0-4 weeks before soil puddling. In plots that received compost early or that received mature compost, the N concentration of the puddled-soil solution and the amount of N uptake by the rice plants were low. When compost at the midpoint of the first fermentation was applied just before soil puddling, rooting was delayed by a few days. However, there was no damage to the growth of the rice in any plot, and the whole crop yield was high (depending on the uptake of N). Yield was resistant to delays in rooting or to improper N supply, because the whole plant is harvested for forage, not just the grain. In addition, the degree of nitrate leaching into the subsoil was low when the compost was immature or was applied late. Consequently, in forage rice cultivation, cattle manure compost can be a highly effective N fertilizer if it is applied after the first fermentation and near soil puddling.

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A total of 122 farmyard manure samples (75 cattle manure, 23 poultry manure and 24 swine manure) collected in Fukushima Prefecture were analyzed for trace elements. The results obtained are summarized as follows: 1) The trace element concentrations were in the order of Na, Fe and Al (the median in all farmyard manure: 4194-4985mg kg^<-1>)>Ti, Mn and Zn (222-578mg kg^<-1>)>Cu, Rb, Sr and Ba (19-87mg kg^<-1>)>Li, V, Cr, Ni, Ga, As, Y, Zr, Mo, Cd, Pb, La, Ce and Nd (0.32-7.53mg kg^<-1>). 2) The concentrations of Li, Al, Ti, V, Fe, Ga, As, Zr and Ba in cattle manure were higher than those in poultry manure, and highly positive correlation coefficients were observed among these elements in many combinations. In contrast, the contents of N, Mg, P, Ca, Ni, Cu, Zn, Sr and Mo in poultry manure were higher than those in cattle manure. The swine manure possessed the chemical properties of both cattle manure and poultry manure, with some exceptions. 3) The concentrations of Cd, As and Pb were generally low in farmyard manure. Although Zn was used as an index to monitor the accumulation of other harmful elements stemming from the application of farmyard manure, higher correlation coefficients were not found among Cu, Zn, Cd, As and Pb when all kinds of manure from different types of domestic animals were taken into consideration. 4) Cu and Zn concentrations were high in poultry manure and particularly high in swine manure, suggesting that care should taken to avoid soil pollution caused by the application of these manure types.

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We investigated the content and solubility of nutrients in cow manure compost heat-treated at 80-180℃ for 2h or carbonized at 200-900℃ for 2h. (1) Carbonization reduced the weight of the compost by between 21.9% at 200℃ and 66.9% at 900℃. P, K, Ca, and Mg contents remained almost the same, but N was volatilized by between 17.7% at 200℃ and 88.4% at 900℃. (2) Heat treatment reduced the content of NH4-N by between 6% at 80℃ and 72.4% at 180℃. It similarly reduced the content of acetic acid-soluble N by 34.5%-71.7% and of phosphoric acid-soluble N by 12.8%-46%. Carbonizing at 400℃ or higher eliminated elutable N. (3) Carbonization reduced the content of water-soluble P. Most P was insoluble in water but soluble in citric acid. Carbonization had little effect on water-soluble K. Increasing carbonization temperature increased the content of citric acid-soluble (water-insoluble) K and citric acid-insoluble K.

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