Soil acidity reconstruction based on tree ring information of a dominant species Abies fabri in the subalpine forest ecosystems in southwest China

To assess the suitability of dendrochemistry as an indicator of soil acidification, soil chemistry and tree ring information of Abies fabri were measured at two distinct sites (severe acid deposition site-Emei Mountain and clean site-Gongga Mountain) of the subalpine forest ecosystems of western Sichuan, southwest China. The actual soil acidity (pH) was significantly correlated with some of the recent xylem cation (Ca, Mg, Mn, Al, Sr and Ba) concentrations and their molar ratios. Xylem Ca/Mg and Ca/Mn of A. fabri were ultimately selected to reconstruct the historical changes of soil pH in Emei Mountain and Gongga Mountain, respectively. The validity of those rebuild was also verified to a certain extent. We conclude that xylem cation molar ratios of A. fabri were superior to the single cation concentrations in soil acidity rebuild at the study sites due to normalizing for concentration fluctuations.     

Impact of mercury on the activity pattern of a marker enzyme in a freshwater bivalve

Sessile benthic organisms are universally accepted as bio-indicators of environmental pollution and lysosomal membrane is often the target of injury by xenobiotics resulting in destabilization. Effect of mercury on the activity pattern of the marker enzyme, Acid Phosphatase in the gill and hepatopancreas of the freshwater mussel, Lamellidens corrianus (Lea) at 24, 72, and 168 h, post-exposure discussed. ACP activity was determined as given in Sigma Technical Bulletin (No. 104) and μmol of p-nitrophenol liberated/mg protein/h calculated. The work aimed to study the duration of exposure and concentration of the metal influence, the direction of the response of the enzyme in the two tissues studied and results show that the concentration of the metal as well as the period of exposure do influence the enzyme activity and may have predictive value as a biomarker of impending population changes. Higher concentration of the metal is assumed to have induced stress proteins like metallothioneins.     

Environmental regulatory failure and metal contamination at the Giap Lai pyrite mine, Northern Vietnam

The causes for the failure in enforcement of environmental regulations at the Giap Lai pyrite mine in northern Vietnam are considered and the environmental impacts that are associated with this mine are evaluated. It is shown that sulphide-rich tailings and waste rock in the mining area represent significant sources of acid rock drainage (ARD). The ARD is causing elevated metal levels in downstream water bodies, which in turn, represent a threat to both human health and to aquatic ecosystems. Metal concentrations in impacted surface waters have increased after mine closure, suggesting that impacts are becoming progressively more serious. No post-closure, remediation measures have been applied at the mine, in spite of the existence of environmental legislation and both central and regional institutions charged with environmental supervision and control. The research presented here provides further emphasis for the recommendation that, while government institutions may need to be strengthened, and environmental regulations need to be in place, true on the ground improvement in environmental quality in Vietnam and in many other developing countries require an increased focus on promoting public awareness of industrial environmental issues.     

酸雨条件下城市农业土壤镉的释放研究

本文选取成都市典型农业土壤为研究对象,根据成都市降雨特征,模拟一定范围pH及主要阴、阳离子浓度配制成母液开展酸雨淋滤实验,以确定酸雨中影响土壤重金属元素镉溶解度的关键因素,探明其对镉释放的影响程度。研究结果表明,总体上酸雨加速了土壤镉的释放。不同类型土壤在同一酸雨条件下,镉的释放速度和最大释放量也不同。酸雨pH值和主要阴、阳离子浓度对镉释放的影响有明显的规律。     

南京地区的酸雨趋势分析

介绍了南京地区酸雨的分布特征及发展趋势。自１９８９年以来，南京市浦口降水年均ＰＨ值有明显波动性下降。研究表明，局地污染对南京酸雨的影响较为明显。     

酸沉降对重庆农业生态的影响

本文阐述了酸雨、酸雾、SO_2等主要酸沉降单独对重庆植物、土壤的作用及其复合作用,提出了今后的研究方向及减少危害的措施。     

漆酶催化复合染料酸性黑ATT脱色的研究

利用白腐菌Ganoderma lucidum wz-32发酵制备的漆酶对印染工业常用的复合染料酸性黑ATT进行催化脱色.在单因子试验的基础上,通过正交优化试验确定酸性黑ATT的最佳脱色条件为:温度50℃,染料浓度0.1 g·L-1,酶量9 U·mL-1,pH 5.0,最适条件下酸性黑ATT的脱色率达87.35%.同时研究了金属离子、酶抑制剂、脱色助剂对酸性黑ATT脱色的影响,结果表明,Co2+、Fe2+、Mn2+、Ca2+、I-对脱色有抑制作用,10mmol·L-1的浓度使脱色率降低了50%以上;Na+、Cu2+在低浓度时对脱色有一定的促进作用;SDS显著抑制漆酶的催化脱色作用,浓度为10mmol·L-1时脱色率降低了68%;HBT是高效的脱色助剂,可显著提高漆酶的脱色效率.     

江苏省酸雨污染现状及趋势分析

依据江苏省部分城市的酸雨监测资料，对该省酸雨污染现状及“八五”以来的变化趋势进行了分析，结果表明：淮河以南酸雨污染普遍重于淮河以北地区；酸雨频率有降低的趋势，但降不酸度并未减弱；降水组份中，硫酸根离子当量浓度仍占首位，酸雨带来的污染和生态破坏未得到明显减轻。     

我国东南部硫氧化物输送沉降模拟研究

介绍了一个简化的欧拉酸沉降模式,模拟中国东南部硫氧化物(SO_x)输送?转化和沉降过程的计算结果,并对计算结果进行了分析讨论      

离子色谱法测定酸雨中6种阴离子

离子色谱法测定酸雨中６种阴离子，以流速为１．５１ｍＬ／ｍｉｎ，０．２４ｍｏｌ／Ｌ Ｎａ２ＣＯ３和０．３ｍｏｌ／Ｌ ＮａＨＣＯ３的混和液为淋洗液，在ＹＳＡ８型８００１Ａ－４阴离子交换柱上分离，ＹＳ－１抑制器，ＹＩＣ－８型离子色谱仪电导检测器检测，方法的线性范围均为１００倍，可达２００倍以上，以ＣＩ＾－为例，最小检出限为０．００１，重现性ＣＶ％为０．７６，空白检测偏差Ｓｗｂ＝０．００６８１，回收率为９