中国土壤重金属污染现状及生物修复技术研究进展

综述了中国土壤重金属污染物的主要来源、土壤重金属污染现状、重金属土壤的生物修复机理机制及研究进展,并对土壤重金属污染防治存在的问题和发展趋势进行了探讨。     

污染土壤修复技术研究进展

土壤是人类生产活动的重要物质基础,随着社会经济的高速发展和高强度的人类活动,土壤受污染面积不断扩大,土壤质量持续恶化,影响到实现可持续发展的战略目标。由土壤污染导致的农产品的生态安全问题已不容忽视。因此,开展污染土壤修复活动,完善土壤修复技术体系,对阻断污染物进入食物链,防止对人体健康造成危害,实现社会经济可持续发展是非常重要的。该文系统介绍了目前国内外污染场地修复中广泛使用的物理修复技术、化学修复技术、生物修复技术(包括植物修复、微生物修复和动物修复技术)以及相关技术结合使用的联合修复技术,并对各种方法的研究进展进行了较全面的综述,最后也对未来土壤污染修复技术的发展方向进行了展望。     

Assessment of the removal efficiency of fish farm effluents by grey mullets: a nutritional approach

A field study was carried out to assess the use of the bottom‐feeding grey mullet (Mugil cephalus) within benthic enclosures as a means to reduce the benthic impacts of a net cage fish farm in the Gulf of Aqaba, Red Sea. Five experimental 1‐m³ net‐cage enclosures were stocked with 12 grey mullets each (fish weights 50, 70 or 144 g). The enclosures had no bottom and the mullets had access to the enclosed organically enriched sediments and to particulate matter (PM) falling from the overlying cages. Sediment traps were used to quantify and qualify the PM falling from the fish farm to the sea floor. Simultaneously, a feeding trial was performed with mullets (50 and 70 g) in experimental tanks. In order to estimate the potential growth rate and to quantify energy and protein requirements, the fish were fed a formulated diet with known composition. After approximately 70 days at sea, mullets in the enclosures had used up all the available food in the sediment and gained up to 0.78 g day^?1 fish^?1. Applying the values for energy and protein requirements for maintenance and growth derived from the experimental trial, estimates indicated that the grey mullets effectively removed 4.2 g organic carbon, 0.70 g nitrogen and 7.5 mg phosphorus kg^?1 mullet m^?2 day^?1 from the organically enriched sediment. Thus deployment of grey mullets may be an efficient means to improve the quality of sediments below intensive net‐cage fish farms.     

菊花心江蓠在网箱养殖区的生物修复作用

2003年8～12月，利用菊花心江蓠(Gracilaria lichenoides)在福建省东山县八尺门网箱养殖区进行生物修复实验。通过定点跟踪监测，定点连续监测，断面监测和平面监测，结果表明，江蓠对受污染的海水具有较好的修复效果。菊花心江蓠能有效提高水中的DO浓度，使修复实验区的DO浓度明显高于非养殖区和网箱养殖区的DO浓度；菊花心江蓠还能降低水中的IN、IP浓度，特别是3种价态的IN中，菊花心江蓠优先吸收铵氮，这对减轻网箱养殖区自身污染的影响更具实际意义。     

矿区森林生态恢复生物技术工程系统分析

简要阐述我国矿区森林生态环境的破坏现状,介绍废弃矿区森林生态环境修复中生物技术的类型、特点及应用情况;并以植物修复、微生物修复为例,结合林业系统工程和恢复生态学,对生物技术在森林生态恢复全过程中的应用做系统分析。     

富营养化对湖泊的危害及修复技术探讨

描述了我国湖泊富营养化污染的现状,阐述了其特征及危害,探讨了几种湖泊富营养化的修复技术并比较了各自的优缺点。     

丛枝菌根真菌(Glomus caledonium)对铜污染土壤生物修复机理初探

利用盆栽试验,研究了丛枝菌根真菌(Glomus.caledonium)在不同程度铜污染土壤上对玉米苗期生长的影响。结果表明,即使在土壤施铜量达150mg/kg时,菌根真菌对玉米仍有近55%的侵染率;接种菌根真菌,能显著促进玉米根系的生长。菌根玉米的根系生物量和根系长度,平均较未接种处理分别提高108.4%和58.8%;接种处理的植株地上部生物量达到每盆(3株)10.58g,显著高于不施铜的非菌根玉米。这些结果表明,丛枝菌根真菌对铜污染具有较好的抗性;并且由于菌根的形成,使宿主植物明显地改善了对磷的吸收和运输,并能通过抑制土壤酸化、降低土壤可溶态铜的浓度等机制,增强宿主植物对铜污染的抗(耐)性。在150mg/kg施铜水平时,与非菌根玉米相比,菌根玉米地上部和根系铜浓度分别降低24.3%和24.1%,吸铜量分别提高了28.2%和60.0%,表明菌根植物对铜污染土壤具有一定的生物修复作用。     

均匀电场下两株多环芳烃降解菌在土壤中的迁移及电动注入

采用电动注入装置,研究了枯草芽孢杆菌和白腐真菌在均匀电场作用下在土壤中的迁移特征,以及这两种微生物电动注入的效果.结果表明,枯草芽孢杆菌和白腐真菌可通过电泳和电渗两种作用在电场下迁移,电泳起主导作用,微生物向阳极迁移为主.在所研究土壤中,微生物的迁移速率分别为:枯草芽孢杆菌13.5 cm·d-1,白腐真菌18.0cm·...     

石油污染土壤生物修复过程中毒性的植物指示

为探究石油污染土壤生物修复过程中土壤生态毒性的变化规律并完成指示生物和指标的筛选,采用前期筛选和分离的三株对石油烃有良好降解效果的降解菌构建了混合菌体系,开展了石油污染土壤模拟生物修复实验,考察了不同修复时期小麦和萝卜种子的发芽率和幼苗生长发育状况(株高、地上部鲜重、根鲜重、根干重)及叶片的malonaldehyde(MDA)含量、光合色素含量(叶绿素a和类胡萝卜素)、superoxide dismutase(SOD)活性的变化。结果表明:微生物修复8 d和16 d的土壤,其生态毒性较强;前期土壤的生态毒性有所上升,随后有所降低,在整个修复时期土壤均存在一定的生态毒性;不同的指示植物、指示指标对石油污染的响应存在一定的差异。幼苗生长发育指标(株高、地上部鲜重、根鲜重)以及叶片SOD活性、MDA含量等指标均能较好指示整个石油污染土壤微生物修复过程中的生态毒性,可作为石油污染土壤微生物修复效果的指示生物和指标。     

A review on phorate persistence, toxicity and remediation by bacterial communities

Pesticides are an integral part in maintaining agriculture and horticultural productivity and play a vital role in meeting the increasing food, fiber, and fuel needs of the growing population. Globally, organophosphate pesticides(OPPs) are among the most common pesticides used due to their high proficiency and relatively low persistence in the environment. However, recent studies have reported problems due to pesticide use, e.g., phorate contamination of aquatic ecosystems(fresh and groundwater), sediments, fruits and vegetables, and forage crops. This review highlights many cases where phorate has been detected above its respective maximum residue limit values. Organophosphate pesticides, including phorate, have negative impacts on both the environment and human health. The ecological and public health concerns of recurrent pesticide utilization have encouraged the research related to environmental fate of pesticides.Bioremediation is an effective, eco-friendly, and financially viable approach for the decontamination and degradation of toxic OPPs from the environment,compared to the costly, unecological, and time-consuming physicochemical approaches, which lead to the generation of byproducts of higher toxicity.Researchers have recognized that a wide range of microbes, mainly bacteria, can degrade this extremely hazardous pesticide. Therefore, this review discusses the present pesticide scenarios, especially phorate contamination, its toxicity, biodegradation, and metabolic products via bacterial communities, both in India and globally. The latest and up-to-date literatures on the use, contamination, and bacterial application of phorate degradation are also summarized. This article offers national and international food safety organizations and public health authorities the ability to be involved in preventing the risks associated with the use of food and nutrition products contaminated with extremely toxic phorate pesticide. This article would also enable researchers to develop comprehensive and sustainable methods to effectively remediate pesticide-contaminated environments. In conclusion, it is envisaged that the successful application of bacterial communities for degradation of phorate would help in understanding the fate and persistence of such toxic pollutants in a better way.