焦化场地典型多环芳烃类污染物精细化风险评估

为准确评估多环芳烃(PAHs)污染土壤对人体的健康风险,解决目前基于总量风险评估导致土壤PAHs修复目标值过严的问题,采用德国标准研究院颁布的生物可给性测试方式研究了石家庄某焦化厂土壤中苯并[b]荧蒽(BBF)、苯并[k]荧蒽(BKF)、苯并[a]芘(BAP)、茚并[1,2,3-cd]芘(IPY)和二苯并[a,h]蒽(...     

Dissipation of chlorpyrifos in pakchoi-vegetated soil in a greenhouse

The dissipation of chlorpyrifos in pakchoi-vegetated soil was investigated in the summer and autumn in a greenhouse and field, respectively. The dissipation of chlorpyrifos in pakchoi-grown soil was comparatively described by fitting the residue data to seven models （lst-order, 1.5th-order, 2nd-order, RF lst-order, RF 1.5th-order, RF 2nd-order, and bi-exponential or two-compartment models）. Statistical analysis was performed using the SPSS 11.5 statistical package. The bi-exponential model was selected as the optimal model according to the coefficient of determination r^2. The dissipation half-lives （DT50） of chlorpyrifos in pakchoi-vegetated soil at the recommended dose in the summer and autumn, calculated by the bi-exponential model, were 0.6 and 1.2 d in a greenhouse, 0.4 and 1.0 d in a field, respectively; the corresponding values at double dose were 1.2 and 2.1 d in a greenhouse, 0.5 and 1.3 d in a field, respectively. The kinetic data indicate the dissipation of chlorpyrifos in pakchoi-grown soil in a greenhouse is slower than that in a field, and dissipates slower in the autumn than in the summer.     

Selection of appropriate organic additives for enhancing Zn and Cd phytoextraction by hyperaccumulators

Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid （EDTA）, citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid （MGWL） from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent （MR） and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration.     

1997～2004年中国区域经济与火灾态势的关系分析

中国区域经济发展存在较大差异,相应的火灾,隋况也各不相同,本文通过对1997～2004这8年期间的火灾数据的分析,探讨了火灾发展态势在不同地区的特征,并分析了典型地区的火灾和社会经济发展之间的关系。结果表明,当前情况下,随着经济的发展,我国多数地区的火灾发生态势先升高后降低,最后保持平稳;经济较发达的上海地区的火灾发生率已经越过了“最高峰”而趋于平穗好转的时期,此外,同样是经济较发达北京与天津两地的火灾发生率正处于“最高峰”时期,预计在未来几年内其火灾发展将趋于好转。     

中国ESG政策探索与实践进展研究

践行环境（E）、社会（S）和治理（G）理念是全面推进美丽中国建设的重要举措,也是企业现代绿色治理的关键手段。本文系统分析了我国ESG政策的发展脉络,将ESG在我国的发展分为萌芽起步阶段、探索发展阶段和深化提升阶段三个阶段。通过深入剖析我国ESG体系现存的若干问题,提出加大推广和实践ESG理念的力度和深度、分批分阶段有序推进ESG信息披露标准制定、加快构建具有中国特色的ESG评级标准、强化对ESG投资的指引和规范,以及加快建设健全的ESG监管体系等政策建议。     

应用XAD系列树脂分离和富集天然水体中溶解有机质的研究进展

溶解有机质(dissolvedorganicmatter,DOM)是一类由腐殖质和非腐殖质构成的非均质混合物,广泛存在于土壤、煤炭和水体中,产生重要的生态环境效应。溶解有机质中相似组分的分离一直是有机质研究的难点。近年来,随着XAD树脂分离技术在DOM分离中的广泛应用,腐殖质和非腐殖质的分离取得了很大进展,文章对这些方法进行了详细的综述,并做了进一步的展望。     

安徽省升金湖湿地土壤有机碳储存及分布

文章研究了安徽省升金湖湿地土壤有机碳储存和分布特征及其与土壤氮素的关系。结果表明,供试湿地土壤全土1m深有机碳密度达10.82±1.90kg.m-2,表层土壤(0—30cm)有机碳密度为5.19±0.68kg.m-2,高于报道的人工湿地——水稻土的碳密度;有机碳(SOC)含量分布随土壤深度(H)的递降符合幂函数方程,湿地土壤有机碳的表层积累强度和积累深度高于稻田;湿地土壤氮素是土壤固碳的有利因子,其氮素对土壤有机碳积累的效应高于水稻土;因湖泊沉积受河流动力学、土壤水分和植物生长条件的影响,湿地土壤有机碳含量存在显著的水平空间变异性。看来,长江中下游淡水湿地在陆地生态系统碳氮储存上具有重要意义。     

某建筑结构火灾后的加固处理

对某建筑结构火灾中的受损情况进行了现场调查,并对火灾后的结构性能进行了检测。通过分析检测结果,综合评定了结构的受损情况,针对受损伤较重的结构制定了具体的加固维修方案。采用外包钢板法加固受损梁、柱结构,以现浇楼面板置换受损的空心板,加固后的结构完全能满足使用要求。此经验可为类似的建筑结构加固处理提供参考。     

黑龙江省的灾害地貌

地貌是研究地球表面成因、形态发生发展的科学,在自然地理环境中,地貌是主导因素之一。因为它影响着水、热、光、气的重新分配。地面物质的迁移和积累,制约着水文、气候、土壤、植被的特征、类型、分布和发展变化, 以及“旱”、“涝”、“风沙”等灾害的发生,水土流失的强度,地下水的贮存等自然地理过程。     

揭开青藏高原神秘面纱

在广袤的青藏高原蕴藏着哪些资源? 它的自然环境正在发生怎样的变化?在这个空寂荒凉的地方是否有过古人类活动? 为了回答这些问题,过去6年间,我国近千名地质工作者行程25万公里,进行了史无前例的青藏高原中比例尺地质调查,在矿产地质、生态环境、古人类学调查等方面取得了重要的新发现,初步揭开了世界屋脊上的神秘面纱。“青藏高原将成为我国新的铜矿基