Recently, animal-waste composts have been extensively used for open culture systems according to area farming practices. This has resulted in the accumulation of specific nutrients and disruption of base balance. The study reports the accumulation of excess potassium and disruption of base balance due to extensive use of animal-waste composts as fertilizers at fields where black spots are frequently found in broccoli heads. In addition, the relationship between excess fertilization with potassium and development of downy mildew was observed. Excess fertilization with potassium decreased calcium and magnesium content in broccoli, decreased oxidation of lipid-like substances, and caused downy mildew. Thus, it was concluded that the major causes for the occurrence of black spots on broccoli heads in the production fields were excess accumulation of potassium and disruption of base balance due to extensive use of animal-waste composts. We speculate that the metabolism of the products was disturbed and the resistance to downy mildew might have lowered. It should also be noted that physiological disorders occur depending on the type of soil and products, and the growth process.

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This study was conducted to evaluate the effects of palm shell filter strips on mitigating soil and nutrient losses under simulated tropical rainfall. Humic Acrisol of sandy loam soil was compacted in four small scale plots of stainless steel with 0.11 m wide, 0.15 m high and 1.30 m long at 1.56 ± 0.05 g/cm³ being similar to the field condition at Bertam River watersheds in Cameron Highlands of Malaysia. The first plot was control C without any conservation strategy, the second and third plots had fine FP and coarse palm shell filter strips CP of 20 cm wide at slope toe respectively, and the fourth plot had 20 cm wide Ophiopogon japonicus (Tamaryu) grass buffer strips VG at slope toe. Tropical rainfall pattern having higher rainfall intensity at 53.20 mm/h in the beginning for an hour and then followed by 23.00 mm/h for 3 hours was repeated 4 times. Overland and percolating discharge was measured and both water was sampled at certain intervals for analyzing the losses of soil, total nitrogen and total phosphorus components. The experimental results indicated that soil loss from CP was significantly 236.28, 62.59 or 136.53 times lower than those from other three plots of C, FP or VG, respectively. The same tendency as soil loss was observed for nitrogen and phosphorus losses. The losses of nitrogen or phosphorus from CP were significantly 2.08, 1.56, 1.54 or 9.37, 7.05, 9.00 times lower than those from C, FP and VG plots, respectively. Through this study, it was concluded that coarse palm shell filter strips can be an alternative conservation strategy for mitigating soil and nutrient losses effectively at farm level.

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Issue of sediment deterioration in semi-enclosed sea due to eutrophication and stratification has been unsolved for a long time. The question, how to maintain biological production process by improving sediment condition, must be one of the most challenging themes for enhancement of marine resources. Various methods have been examined to clear this problem and developed such as dredging or sand covering, though, those require both huge cost for its construction and huge external energy for maintaining its function for long period in order to realize its purpose in the vast coastal area. Thus we propose this new method that improves sediment condition by current control at the bottom layer by means of ocean energy, tidal current, using our distinctive structure for increase of the dissolved oxygen concentration in the bottom layer water in the long term that realizes improvemet of sediment condition. In this study we examined the current condition around the structure by both numerical calculation and hydraulic experiment. Result of this survey apparently demonstrates that installation of the structure generates vertical mixture of the bottom seawater. Meanwhile, we monitored the fluctuation of sulfide, COD and oxidation reduction potential of the sediment around the structure to grasp the long term effect of the structure installation. Furthermore, it is known that this structure provides a massive amount of zooplankton around it and we measured the large number of aggregation of the black rock fish, Sebastes inermis, gathering around the structure. It is the remained task to clarify the relationship between these facts.

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Asbestos fiber crystals were efficiently degraded by hydrofluoric acid, but not hydrochloric acid, sulfuric acid and nitric acid. Asbestos fiber crystals were completely degraded by 15% hydrofluoric acid within 2 hours at room temperature. The results of TEM micrographs, corresponding selected area diffraction patterns (SADP) and X-ray diffraction measurements obviously demonstrated that asbestos fiber crystals were reacted with hydrofluoric acid to generate magnesium fluoride and magnesium hexafluorosilicate. A high concentration of hydrofluoric acid remained in a wastewater after treatment of asbestos with 15% hydrofluoric acid for 2 hours was properly processed. After having processed the wastewater, the concentration of fluorine ion was 1.8 mg/l. These results suggest that the method consisting of a degradation of asbestos with hydrofluoric acid and a subsequent processing of wastewater may be useful for removing resolution of asbestos.

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The effect of photoperiod on the flowering of Eruca sativa Mill. was studied. Plants were exposed to an 8-hrs photoperiod under natural daylight. The photoperiod was extended with 60 W incandescent lamps to give an 10-to 16-hrs, a day. Under photoperiods at and above 13-hrs, flower buds were initiated; the days from bud formation to flowering were shortened in plants grown under a 16-hr photoperiod, or if the night was interrupted for 2 hrs starting at midnight.

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Biogenic volatile organic compounds (BVOCs) emitted by plants play an important role in the atmospheric chemistry of the troposphere. We conducted f ield measurements of monoterpene emissions from leaves of Chamaecyparis obtusa, which is one of the major tree species in Japan. Diurnal and seasonal variations of monoterpene emissions from C. obtusa were measured at the Kiryu Experimental Watershed (KEW) at 34°58′ N, 135°59′ E in Shiga Prefecture, central Japan. In August and October 2006 and in January and April 2007, the monoterpene emission rate (E), together with the leaf temperature, was measured using branch enclosure methods for a branch of two trees. The obtained data sets revealed that E highly correlated with leaf temperature throughout the seasons. The basal emission rate (E_S) under the standard conditions of 30°C, calculated using a widely used emission algorithm, ranged from 0.088 and 4.126 μg g^-1 h^-1. The estimated E values were consistent with the measured E values within a root-mean-square (RMS) error of 0.005-0.525 μg g^-1 h^-1, suggesting that the emission model can be used to determine the monoterpene emission responses of C. obtusa to temperature. However, the E_S values were significantly different between the trees and also different between seasons, indicating that a representative E_S value must be obtained from more data sets using more branches and trees.

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