Subtropical urban turfs: Carbon and nitrogen pools and the role of enzyme activity

Urban grasslands not only provide a recreational venue for urban residents, but also sequester organic carbon in vegetation and soils through photosynthesis, and release carbon dioxide through respiration, which largely contribute to carbon storage and fluxes at regional and global scales. We investigated organic carbon and nitrogen pools in subtropical turfs and found that dissolved organic carbon(DOC) and dissolved organic nitrogen(DON)were regulated by several factors including microbial activity which is indicated by soil enzymatic activity. We observed a vertical variation and different temporal patterns in both soil DOC, DON and enzyme activities, which decreased significantly with increasing soil depths. We further found that concentration of soil DON was linked with turf age. There were correlations between grass biomass and soil properties, and soil enzyme activities. In particular, soil bulk density was significantly correlated with soil moisture and soil organic carbon(SOC). In addition, DOC correlated significantly with DON. Significant negative correlations were also observed between soil total dissolved nitrogen(TDN) and grass biomass of Axonopus compressus and Zoysia matrella. Specifically, grass biomass was significantly correlated with the soil activity of urease and β-glucosidase. Soil NO3-N concentration also showed negative correlations with the activity of both β-glucosidase and protease but there were no significant correlations between cellulase and soil properties or grass biomass. Our study demonstrated a relationship between soil C and N dynamics and soil enzymes that could be modulated to enhance SOC pools through management and maintenance practices.     

Analysis of the influencing factors of PAEs volatilization from typical plastic products

The primary emphasis of this research was to investigate the foundations of phthalate(PAEs) pollutant source researches and then firstly confirmed the concept of the coefficient of volatile strength, namely phthalate total content in per unit mass and unit surface area of pollutant sources. Through surveying and evaluating the coefficient of volatile strength of PAEs from typical plastic products, this research carried out reasonable classification of PAEs pollutant sources into three categories and then investigated the relationship amongst the coefficient of volatile strength as well as other environmental factors and the concentration level of total PAEs in indoor air measured in environment chambers.Research obtained phthalate concentration results under different temperature, humidity,the coefficient of volatile strength and the closed time through the chamber experiment. In addition, this study further explored the correlation and ratio of influencing factors that affect the concentration level of total PAEs in environment chambers, including environmental factors, the coefficient of volatile strengths of PAEs and contents of total PAEs in plastic products. The research created an improved database system of phthalate the coefficient of volatile strengths of each type of plastic goods, and tentatively revealed that the volatile patterns of PAEs from different typical plastic goods, finally confirmed that the coefficient of volatile strengths of PAEs is a major factor that affects the indoor air total PAEs concentration, which laid a solid foundation for further establishing the volatile equation of PAEs from plastic products.     

浅谈石油企业如何做好环保规划

根据环境保护面临的形势和发展趋势,对企业环保现状和存在的主要问题进行了分析和评价,论述了企业做好环境保护规划的必要性。提出了石油企业制订环保发展战略规划的步骤和做好环保规划的方法,对编制出切合实际、经济可行的环境保护规划有借鉴意义。     

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。     

冷原子荧光法测定水中痕量汞的改进

对冷原子荧光法测定地表水及工业废水中汞的分析处理方法提出改进措施，改进的方法准，快，简，省，符合监测规范要求。     

中国古代生态安全与可持续发展

中国自然生态优越但脆弱。农业历史悠久,但盲目扩大农耕造成生态破坏,威胁生态安全与可持续发展。由于中国古代农牧业分区发展,农耕灌溉施肥,精耕细作,保护了土地资源。农业中心由黄河流域逐步迁移到长江流域,维持了可持续发展,但经验教训十分深刻。     

中荷水处理示范研究培训中心的工作领域与思路

中荷水处理示范研究培训中心是中荷合作的产物,今后将对中国各城市污水处理技术人员、高校师生等进行培训,为建设和管理污水处理厂提供技术咨询,开展污水处理新技术的开发与推广,并开展对内对外的合作与交流。     

生猪养殖适度规模:产出、效益与环境——基于全国8省份1484个养殖户数据的实证

近年来，我国生猪养殖市场产生了剧烈波动，也催生了对生猪养殖适度规模问题的思考。本文基于8省份1484份生猪养殖户的调查数据，采用Translog生产函数和C-D生产函数，从产出、效益和环境三个维度对生猪养殖规模效应进行实证研究。研究表明：生猪养殖规模与环境污染之间存在倒“U”形关系；综合考虑产出、效益和环境三个方面，适度规模应为年出栏1000~1999头；养殖经验对生猪养殖的产出和效益影响显著，环保认知和参加培训状况对环境污染影响显著。基于此，积极引导养殖户合理科学扩大养殖规模、增强环境意识，提升生猪养殖从业人员长期经营的驱动力，对促进养殖行业绿色发展具有重要意义。     

高岭土制备聚合氯化铝新工艺

介绍了以高岭土为原料，经盐酸预处理后，加水聚合、调整反应液pH，制备液体聚合氯化铝净水剂的新工艺。对所得产品的净水性能和技术指标进行了测定，结果表明，采用该工艺制得的聚合氯化铝产品技术指标符合GB1592－95标准。     

基于顶板离层监测的锚固巷道稳定性控制

在提出顶板离层概念的基础上 ,对顶板离层与锚固系统的变形协调条件以及离层临界值、失稳临界值及工程估计值的确定进行了分析 ;通过实例 ,说明了离层监测与反馈的应用 ;工程实践表明 ,采用顶板离层监测是锚固巷道稳定性控制的简易技术手段 ,其技术经济效果明显 ,是一种值得推广的实用方法