Treated wastewater irrigation effect on soil, crop and environment： Wastewater recycling in the loess area of China

A study was carried out at the Loess Plateau in Dongzhi,China,to test the feasibility of using secondary treatment sewage effluent and to determine whether the water quality would then meet the recommended irrigation norm.Seven crops,including celery,wheat, maize,millet,apples,rapeseed and yellow beans,were tested in the study.Physical and chemical properties of the soil,crop yield and quality and leachate at different soil depths were measured.In most cases,the quality of the crops that made use of treated sewage was not distinctively different from those that did not use treated sewage.However,yields for the former were much higher than they were for the latter.Leachates at different soil depths were analyzed and the results did not show alarming levels of constituents.For a period of approximately 14 months,the treated sewage irrigation had no significant effect on the loess soil and no cases of illness resulting from contact with the treated sewage were reported.With treated sewage irrigation,a slight increase in the organic content of the soil was observed.     

Antioxidant responses to benzo[a]pyrene, tributyltin and their mixture in the spleen of Sebasticus marmoratus

It has been reported that there is an interaction between Benzo[a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin （TBT）, an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase （GPx） activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase （GST） activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH （glutathione） by BaP or TBT alone. MDA （malondialdehyde） contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.     

酸雨与镧对大豆幼苗生长的复合伤害效应研究

为探索酸雨与稀土镧对大豆幼苗生长的复合影响及其内在机制,以重要油粮作物大豆(Glycine max)为材料,研究在模拟酸雨pH分别为3.0、3.5、4.5与稀土镧La(Ⅲ)浓度分别为60、100和300mg·L-1处理下大豆幼苗生长及光合作用的变化.结果表明,相对单一酸雨与镧处理,酸雨与La(Ⅲ)复合处理组中大豆幼苗的生长受抑制程度增大,两者呈协同效应,且pH越低,La(Ⅲ)浓度越高,抑制效应越明显.光合参数的变化规律与生长指标近同,相同处理组各光合参数的降幅不一致,其中最大荧光(Fv/Fm)和叶绿素含量(Chl)的降幅范围分别为9.53%～22.75%和9.14%～24.53%,较净光合速率Pn(22.78%～84.7%)、希尔(Hill)反应速率(15.52%～73.38%)和Mg2+-ATPase活性(14.51%～71.54%)小,表明各光合参数对2个胁迫因子的敏感程度存在差异.进一步相关性分析发现,Pn变化主要受Hill反应速率与Mg2+-ATPase活性的影响,而Chl、Fv/Fm次之.表明酸雨与La(Ⅲ)对植物光合过程各环节的作用机制不同,光合作用受阻是影响植物生长的重要因素之一.     

Review of the remediation strategies for soil water repellency

Many regions of the world are predicted to experience water scarcity due to more frequent and more severe droughts and increased water demands. Water use efficiency by plants can be negatively affected by soil water repellency (SWR). It is timely to review existing techniques to remedy SWR. Ideally remediation addresses the origins of a problem. However, the fundamental mechanisms of how and why SWR develops are still poorly understood. In this review it was hypothesized that SWR occurs where the balance of input-decomposition of organic matter is impaired, due to either increased input or decreased decomposition rates of hydrophobic substances. Direct and indirect strategies to remedy SWR were distinguished. While direct remediation aims at abolishing the causes of SWR, indirect strategies seek to manage sites with SWR by treating its symptoms. The 12 reviewed strategies include applying surfactants, clay, slow-release fertilizers, lime, and fungicides, bioremediation of SWR through stimulating earthworms, choosing adapted vegetation, irrigation, cultivation, soil aeration and compaction. Some of the techniques have been applied successfully only in laboratory experiments. Our review highlights that it is not straightforward to cure SWR based on easily measurable and site-specific soil and vegetation properties, and that long-term, large-scale field experiments are required to improve the understanding of the evolution of SWR as cornerstone to develop cost-effective and efficient remediation strategies. We also identified current research gaps around the diagnosis and prevention of SWR.     

非均相催化臭氧处理高浓度制药废水的研究

非均相催化臭氧是一种对高浓度制药废水进行预处理的有效方法.本研究采用单一活性炭吸附、单一臭氧氧化和臭氧/活性炭联用3种体系对实际制药废水进行预处理,并对处理过程中的工艺参数进行优化.结果表明,相比单一活性炭吸附和单一臭氧降解体系,臭氧/活性炭联用体系能显著提高COD、TOC的去除率及BOD5/COD值,并显示出良好的协...     

灾变性事件引起的消费品产业链价格波及效应研究

为了研究地震等灾变性事件对于消费品产业链内价格传递和市场的影响,本文利用从2008年2月至2009年3月四川省江油市畜产业链进行实证研究,使用向量纠错模型（VECM）和历史分解图（HDG）分析了价格调整的动态效果和沿产业链的因果关系。结果表明,价格的调整关于速度和大小都是不对称的,外生震荡对于该产业链的不同层面产生不同影响,导致价格差益的扩大和价格不完全传递。该方法能够有效地分析灾变事件条件下消费品产业链内价格波及效应问题。     

猪粪秸秆高温堆肥过程中碳氮转化特征与堆肥周期探讨

将猪粪与秸秆以7：1（质量比,以鲜重计）的比例,在自制的强制通风静态堆肥反应箱中进行高温堆肥试验,研究了堆肥过程中碳氮转化特征及其腐熟时间.同时,在堆制的23d中,根据堆温变化采样6次,分析了堆肥样品中各种氮素和碳素含量及其它性质的变化情况.结果表明：堆肥结束时,硝态氮含量增加了103.0%,铵态氮、有机氮、总氮含量分...     

Ash deposition impact on the energy performance of photovoltaic generators

A little known side effect of the atmospheric air pollution is the degradation of photovoltaic (PV) cells’ performance due to the deposition of solid particles varying in composition, size and origin. In this context, an experimental-based investigation is conducted in order to compare the energy performance of two identical pairs of PV-panels; the first being clean and the second being artificially polluted with ash, i.e. a by-product of incomplete hydrocarbons’ combustion mainly originating from thermal power stations and vehicular exhausts. A series of systematic measurements of current intensity, voltage output and solar radiation are executed simultaneously for the clean and the polluted PV-panel, so that the effect of several mass depositions on the PVs’ power output, energy yield and conversion efficiency may be determined. According to the results, a considerable deterioration of the PV-panels’ performance is obtained, i.e. almost 30% energy reduction per hour or 1.5% efficiency decrease (in absolute terms) for ash accumulation on the panels’ surface reaching up to 0.4 mg/cm².     

基于ARDL方法分析福建省资源利用与经济增长关系

运用物质流分析方法以及最新发展的自回归分布滞后模型(ARDL),对福建省1990~2008年资源利用和实际GDP二者关系进行检验和分析.采用了物质流分析指标中直接物质投入来表征区域资源利用量.ARDL边界检验结果表明,资源利用和经济增长间存在稳定的长期均衡关系.进一步通过ARDL模型揭示了区域经济增长对资源利用长期弹性系数,其值约为0.73,通过误差修正模型揭示了短期弹性系数,表明了经济增长到资源利用的长期格兰杰因果关系.对福建省经济增长和资源保护战略提出了政策建议.这一研究思路和方法具有普适性,可以适用于其他地区关于资源利用和经济增长的问题的讨论和研究.     

华北地区1951-2009年气温、降水变化特征

基于华北五省(市)64个基本气象站的1961-2009年逐年逐月气温、降水资料, 利用泰森权重计算了华北地区面平均降水及面平均气温,并建立了7个长序列气象站的气温、降水与面平均值的回归方程,展延了研究区1951-1960年面平均降水和气温资料。对展延后的1951-2009年序列数据,应用Mann-Kendall检验、Mann-Whitney检验、9 a滑动平均等方法进行趋势分析,分析结果显示: 该区59 a间年气温上升了1.5 ℃,年气温序列存在显著上升趋势,年气温序列在1993年前后有一个突变点,年气温距平以1989年为低温期与高温期的分界线,年气温平均每10 a增长2.2%;年降水序列无显著趋势,亦无显著跳跃趋势,年降水距平大致以1976年为多雨期与少雨期的分界线,年降水平均每10 a增长-1.3%。研究成果为深入分析华北地区气候变化规律、未来气候变化影响,以及水资源对气候变化的响应提供了基础。