Environmental impacts of shore-parallel breakwaters along Nagahama and Ohgata, District of Joetsu, Japan

A combination of sedimentological analysis of beach sands, field surveys and the assessment of the empirical methods for the breakwater design is used to investigate the impacts of offshore breakwaters on beach morphology along Nagahama and Ohgata. The results indicate that the nearshore sedimentation has been substantially disrupted due to the features formed behind the breakwaters stopping littoral transport, which led to sediment accretion on the updrift side of the breakwaters, and erosion on their downdrift side. Sedimentological analysis of beach sands made it possible to recognize the dominant process at the sections considered. In fact, the occurrence of strong offshore-going currents, the removal of finer mean grain size and the predominance of high-density heavy minerals led us to deduce that the two sections undergo a natural sedimentary imbalance.     

Mineral content of drinking water in lowland papua

This study presents concentration of nine minerals (Na, K, Mg, Ca, Cl, Mn, Zn, Cd, Pb) in 31 drinking water samples collected in the Papua New Guinea lowland, where coastal villagers draw water from artificial wells blended with sea water, riverside villagers utilize brackish river water, and inland villagers fetch creek or swamp water whose chemical composition is close to rain water. During the dry season, the coastal well water contains 500 mgL⁻¹ of sodium and 50–90 μgL⁻¹ of lead. The inland creek or swamp water contains very small amount of minerals; on the average, for instance, 0.64 mgL⁻¹ of magnesium, 0.84 mgL⁻¹ of calcium, and 4.78 mgL⁻¹ of water hardness (as CaCO₃). From some epidemiological evidence in industrialized countries, these mineral concentrations are judged to be indicative of high risk of cardiovascular disorders.     

Presence of macrolide-lincosamide-streptogramin B and tetracycline antimicrobials in swine waste treatment processes and amended soil.

Little is known about the fate of antimicrobials during common agricultural waste handling procedures. To better define the potential scope of this problem, concentrations of antimicrobials throughout the waste treatment process were estimated based on known antimicrobial usage, and the resulting predictions of high antimicrobial concentrations indicated the need for further investigation. Samples from building pits, a solids settling basin, a holding pond, and soil amended with waste treatment byproducts were therefore analyzed for traditional chemical parameters and macrolide, lincosamide, and tetracycline antimicrobials. Substantial improvements in water quality were observed during the treatment process. While the macrolide tylosin was not detected, chlortetracycline, oxytetracycline, and lincomycin were found at high concentrations throughout the waste treatment process. Oxytetracycline and lincomycin were also detected in soil from a field amended with waste treatment byproducts.     

藏北高原土壤温度的日变化

为了探讨气候变化的规律和原因,于１９９７－０７－０９期间,在藏北高原不同地点分别建立了自动气象站和埋设了土壤温度、湿度观测系统,土壤温度观测数据表明,在６０ｃｍ以上土壤温度存在着明显的时间变化,其变化为正弦曲线,与太阳辐射的时间变化一致,但存在关不同的时间滞后。地表状况、土壤干湿程度及土壤组分等的差异对土壤温度的时间变化振幅及热通量有影响。在藏北高原,由于挖坑埋设探测食品等对土壤温度场的优动可在５