Reuse of effluent water—benefits and risks

There is an increasing trend to require more efficient use of water resources, both in urban and rural environments. A major mechanism that can be used to achieve greater efficiencies is the reuse of water that once would have been discarded into the environment after use. The reuse of water for agricultural irrigation is often viewed as a positive means of recycling water due to the potential large volumes of water that can be used. Recycled water can have the advantage of being a constant, reliable water source and reduces the amount of water extracted from the environment. In addition, in some cases treatment requirements may be need to be less than for water used in an urban environment due to less potential human contact. There are concerns and unknowns, however, about the impact of the quality of the recycled water, both on the crop itself and on the end users of the crops. Water quality issues that can create real or perceived problems in agriculture include nutrient and sodium concentrations, heavy metals, and the presence of contaminants such as human and animal pathogens, pharmaceuticals and endocrine disruptors. Social attitudes to the use of crops that have been irrigated with recycled waters and the resulting impact on market value of crops are also a major consideration. This paper will discuss the benefits from using different types of recycled water and outline the current knowledge and opinions relating to risks such as water quality issues.     

对循环经济模式的思考

循环经济是一种资源闭环利用型经济。发展循环经济是缓解资源约事矛盾的根本出路，是从根本上减轻环境污染的有效途径，是提高经济效益的重要措施，是应对新贸易保护主义的迫切需要，是以人为本，实现可持续发展的本质要求。     

天然材料贻贝壳的应用研究

我国贻贝养殖业迅速发展的同时产生了大量的废弃贻贝壳,如何对其资源化利用成为了研究者关注的热点.综述了贻贝壳的研究利用现状,介绍了其作为钙补充剂、土壤改良剂方面的研究现状,探讨了其在重金属、磷及染料去除方面的应用研究进展,讨论了其作为建筑材料、功能材料以及催化剂等方面的利用进展,并对贻贝壳的再利用的发展方向进行了展望.     

生态园区有机废弃物的循环利用研究

综述了目前我国生态园区有机废弃物的利用状况和存在的问题,特别对园区中常见的餐厨垃圾和果枝修剪废弃物的综合处理技术进行了详细介绍,探讨了生态园区有机废弃物的循环利用途径与发展方向,提出小容量反应器堆肥系统是处理不同固体废弃物的适当途径。可为我国生态园区有机废弃物的开发利用提供参考。     

Ground vegetation has a major role in element dynamics in an ash-fertilized cut-away peatland

In Finland, recycling of wood-ash as a fertilizer has been widely studied in recent decades in peatlands drained for forestry. Wood-ash is reported to promote tree growth without any significant negative impacts on the environment and could, therefore, be a suitable option on cut-away peatlands, which are estimated to increase by 30,000 ha over the next ten years. However, the environmental effects of ash-fertilization on cut-away peatlands or on ground vegetation are not well known. We studied the effects of wood- and peat-ash application on the nutrient content in soil and plants and on the heavy metal content in the vegetation of a cut-away peatland. Six treatments of different quantities and mixtures of wood-ash, peat-ash, biotite, or Forest PK-fertilizer were replicated in three plots. Both wood- and peat-ash fertilization ensured an adequate level of nutrients for the early establishment and growth of ground vegetation and birch seedlings in a cut-away peatland. Dense pioneer moss cover was important in trapping the heavy metals, such as cadmium, which are present in the ash. Ground vegetation of mosses and herbaceous plants also had a major role in the retention of the nutrients that could otherwise have leached from the open cut-away peatland area during the early stages of afforestation. Both wood- and peat-ash proved to be suitable for the initial fertilization of afforested cut-away peatlands, but in order to guarantee a sufficient long-term potassium supply for tree growth, an application of biotite with the peat-ash is recommended.     

吉林省西部地区发展循环经济策略研究

分析了吉林省西部地区发展循环经济的意义,并根据地区特点,提出了发展循环经济战略的策略:以循环经济促进法为指导,制定相关政策法规;加强循环经济理念的宣传、教育和培训,提高循环经济认识水平;建设发展循环经济型工业,走新型工业化道路;强化节能降耗,发展清洁能源;加强循环型农业建设,实现农业经济、生态和社会效益的统一.     

Estimation of Milk Production in Lactating Sows by Determination of Deuterated Water Turnover in Three Piglets per Litter

The milk intake in piglets from four lactating sows was measured in three 48 h periods, starting on days 3, 10 and 17 of lactation, using the deuterium oxide (D 2 O) dilution technique. The milk intake was estimated from the water turnover in the piglets corrected for the production of metabolic water. The water turnover was estimated from the water dilution space and the fractional turnover of body water, determined by the rate of D 2 O dilution. To determine the magnitude of isotopic recycling, a randomly selected piglet in each litter was not enriched with D 2 O. Milk production of the four lactating sows was also measured by the weigh-suckle-weigh (WSW) method on days 4, 11 and 18 of lactation. The average daily milk production determined by the D 2 O dilution technique (9.91 - 0.69 kg) was higher ( P <0.05) than that determined by the uncorrected WSW method (8.65 - 0.81 kg). Different procedures for selecting piglets were evaluated to obtain the best possible estimation of total milk production from three piglets in each litter. The total milk production of a sow based on three piglets in the litter was obtained from a quadratic model of the relationship between milk intake and daily gain. When the daily gain of all piglets were known the Pearson correlation between milk production determined for the whole litter ( n -1) and only three median piglets was 0.98.     

废弃食用油脂资源化利用研究进展

废弃食用油脂主要含有甘油三脂和脂肪酸类有机物,易腐化变质滋生毒害物质,危害人类健康、污染环境。另一方面,废弃食用油脂回收利用合理则是一种资源,可作为生产洗涤剂、脂肪酸、混凝土制品脱模剂、生物柴油等化工和能源产品的原料,也可作为制备生物表面活性剂、单细胞蛋白等生物产品的有机碳源。简述了废弃食用油脂的危害,详细介绍了国内外常用的废弃食用油脂资源化利用方法,并展望了废弃食用油脂资源化利用的研究方向。     

废纸在人造板领域中的回收利用技术及研究进展

综述了国内外利用回收废纸制造人造板技术研究进展,分析了废纸在人造板领域回收再利用技术的发展趋势,阐述了废纸与木质材料制备复合材料存在的三大问题,并提出了对策。     

盐城市农业废弃物资源化利用的现状、存在问题及建议

为治理农村污染,农业部明确了“一控、两减、三基本”的目标,主要是通过资源化利用的办法从根本上“控制农业用水的总量,减少化肥农药的施用总量,解决畜禽养殖污染、地膜回收和秸秆焚烧等问题”。阐述总结盐城市农作物秸秆能源化、肥料化、基料化、饲料化和工业原料化方面的利用,畜禽水产养殖污染治理和农业投入品等废弃物资源利用的进展,分析目前存在的问题,并提出下一阶段的工作建议。