Range of ecological impact of highway construction in the Longitudinal Range-Gorge Region,China

The major features of different road sections were identified. Methods quantitatively determining the ecological impact of highway construction were discussed, and a demonstration was presented. The Dabao highway (from Dali to Baoshan) and the Sixiao highway (from Simao to Xiaomengyang) passing through the Longitudinal Range-Gorge Region were used as examples in this paper. For the normal road sections having no important species to protect, a method of ecosystem health assessment was introduced to calculate the overall range of the ecological impact of highway construction. For the road sections having plants or soils of interest, indexes were selected and the range of impact was determined using mathematical methods such as regression analysis and variance analysis. The range of impact on animal populations was also discussed in terms of the minimum living areas required by animal populations and the fragmentation caused by highway construction. The results indicate that the zones impacted by highway construction were composed of both regular and anomalous figures, the range of impacts for different landforms of the two sample highways were substantially different; highway construction had dramatic effects on roadside ecosystem health; the impact on soil factors of farmland was greater than 200 m, and the distance may exceed 1000 m when important large animals were considered.     

Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4–12. The rates of phosphine production and release from lake sediments varied with temperature. 20°C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes.     

Inhibition effect of magnetic field on nitrous oxide emission from sequencing batch reactor treating domestic wastewater at low temperature

This study aims to investigate the effect of a magnetic field on nitrous oxide(N_2O) emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N_2O for a magnetic field-sequencing batch reactor(MF-SBR) decreased by34.3% compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN) and ammonia nitrogen(NH4-N) of the MF-SBR were 22.4% and 39.5% higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira) and denitrifiers(Zoogloea),which could reduce N_2O to N_2,were promoted significantly in the MF-SBR.Enzyme activities(Nir) and gene abundances(nos Z nir S and nir K) for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N_2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature.     

岷江干流表层沉积物中磷形态空间分布特征

近些年,岷江水体TP污染情况严重,而水体沉积物这一潜在污染源,对水质安全带来的威胁也不容忽视.为揭示岷江干流表层沉积物中磷形态的空间分布特征,于2016年12月,采集了岷江干流(阿坝~宜宾)表层沉积物样品,应用改进的SEDEX法对表层沉积物中的弱吸附态磷Ex-P、可提取态有机磷Org-P、铁结合态磷Fe-P、自生磷灰石磷Ca-P、碎屑磷De-P和非活性磷Res-P等6种磷形态质量浓度进行了测定.结果表明,岷江干流表层沉积物中总磷TP的质量浓度为522.17~979.22μg·g~(-1),已远超全国土壤磷素背景值700μg·g~(-1),表明岷江沉积物中TP浓度较高.从空间分布来看,岷江中游眉山河段中的表层沉积物是颗粒最细、有机质和TP质量浓度最高的区域.岷江干流表层沉积物磷的主要赋存形态为Ca-P和DeP,两者共占TP的质量分数为75%以上.同时,岷江干流表层沉积物中的生物可利用磷(Ex-P、Org-P和Fe-P总和)占TP的质量分数为10.31%~29.62%,其中以中游河段(尤其是眉山段、乐山段)质量浓度最高,这表明岷江中游河段表层沉积物中磷的生物可利用性较强,潜在环境风险较高.     

吹扫捕集-色质联机测定水中挥发性硫醚

采用吹扫捕集-色质联机测定水中挥发性硫醚,采用外标法,使用SIM模式对甲硫醚、乙硫醚和二甲二硫醚三种成分进行定量,方法的检出限分别为0.02、0.05和0.08μg/L,三种物质浓度在0.40~40μg/L范围内,测定结果有良好的线性,一次回归曲线的相关系数分别为0.9998、0.9999和0.9999。利用该方法对内河等实际样品进行分析,结果平行性良好,加标回收率在75.2%~88.4%之间。     

用于处理含油泥砂的菌种性能实验研究

对从孤东油田原油污染的土壤中筛选出三株可以降解原油的细菌进行的实验结果表明,所筛选的细菌能够很好地利用油泥砂中的原油作为碳源而进行生长代谢,从而达到降解原油的目的。同时,细菌还可利用油泥砂中的原油在生长代谢过程中产生生物降解表面活性剂,将原油从泥砂表面剥离下来,并使其乳化、溶解在溶液中。在油泥砂处理初期加入化学表面活性剂,可以促进细菌的生长,缩短处理时间,对最终处理效果没有根本影响。     

排污权的产权性质分析

排污权交易是利用市场机制控制环境污染的有效途径。明确排污权的产权性质无论是对生产者还是对管理者都具有十分重要的意义。本论文将对排污权的产权性质和内涵进行分析。     

不同交联度PP-g-4VP离子交换纤维的制备及对水溶液中铬离子吸附的研究

通过控制交联剂(DVB)及单体(4-VP)浓度等工艺,研制了不同交联度的聚丙烯接枝4乙烯基吡啶离子交换纤维(PP-g-4VP),旨在改善纤维的结构及其再生吸附和重复使用性能。实验结果表明,随着DVB含量增大,纤维的接枝率下降,交联度增加,而吸水率下降。所制的PP-g-4VP和PP-g-4VP-季铵盐纤维对Cr~(6+)静态吸附量大,分别达约6.5mmol/g和4mmol/g。交联度低时,纤维对Cr~(6+)吸附速度越快,穿透点前流出液浓度较低。纤维吸附Cr~(6+)后用1N NH_3·H_2O能完全洗脱,再生吸附性能良好。     

粉煤灰的环境污染与综合利用

在文献调研的基础上,分析了粉煤灰对环境造成的污染及在建筑、筑路、农业等方面的综合利用情况,发现其效益非常明显,每利用1万t粉煤灰,可为火力发电厂节约征地200m~2,减少灰场投资运行费2～8万元.节约灰运费2～5万元。介绍了粉煤灰在废水处理和废气净化方面的应用,在此基础上,讨论了其中存在的问题和解决对策。在净化废水方面,对COD、BOD_5、色度等都有较好的去除作用;在废气净化方面,用粉煤灰作脱硫剂来脱除燃煤烟气中的SO_2,效果良好。