中国农业生态补偿法律制度建设研究

2014年通过的《环境保护法》第31条规定:国家建立、健全生态保护补偿制度.紧随其后,2014年5月苏州市人大常委会正式批准了《苏州市生态补偿条例》,彰显了国家和地方政府对于生态补偿这一法律制度的重视.农业生态补偿作为生态补偿的一个具体分支,法律制度的建设,将对当前中国日趋严重的农业面源污染问题,提供一个现实的解决路径.文中找出农业生态补偿法律制度存在的问题,并提出具体的建设意见,为中国农业生态补偿法律制度的建设提供理论上的支撑.     

当前农业面源污染现状、特征及对策研究

我国是农业生产大国,大量化肥、农药、地膜的过量施用,以及规模化养殖的增加,加剧了农业面源污染。农业面源污染的分散性、隐蔽性、随机性和难监测性等特点,导致对农业面源污染的治理提出了更高要求,需要牢固树立"创新、协调、绿色、开放、共享"的发展理念,积极推广农业清洁生产和标准化生产,大力发展现代生态循环农业,建立农业面源污染监测预警和管理体系,切实解决农业面源污染难题。     

哈尔滨磨盘山水源保护区生态补偿机制的研究

磨盘山水库已成为哈尔滨市人民重要的饮用水源地。解决保护区农药和化肥等造成的面源污染问题的重要措施就是要在这一地区发展建设无任何污染的有机食品基地,这对农民在一定时期内可能会造成局部和暂时的利益损失,因此,必须要有生态补偿机制,才能使保护区发展有机食品成为可行。本文为此疑出了建立磨盘山水源地保护区生态补偿机制的方法及相关措施。     

"水土固共治"助推长江经济带生态保护与绿色发展

农业面源污染作为非点源污染,是长江流域水体污染的重要来源之一。推进长江经济带农业面源污染治理,是加快长江经济带发展的重要政治任务。当前农业传统生产方式仍未发生根本转变,存在养殖污染重、复耕指数大、化肥农药使用不科学等问题,耕地质量下降与面源污染难控的矛盾十分突出,对水环境质量管理提出了严峻的挑战。郧阳区通过开展水土共治、发展环水有机农业的创新实践,探索出以绿色经济驱动农业面源污染治理和农业绿色发展的可持续发展模式,对助推长江经济带生态保护与绿色发展具有重要的示范意义。     

磨盘山水源地保护区内农业生态补偿机制研究

磨盘山水源地一、二级保护区内农药、化肥的污染是磨盘山水源地最主要的潜在污染,是水源地水质保护的最主要难题。在由于资金等问题目前无法解决库区村屯农业人口搬迁的情况下,实施保护区内农业生态补偿机制,鼓励农民发展绿色食品和有机食品是近些年内减少库区水质受农药、化肥面源污染的切实可行的对策。     

中国农业面源污染的区域分异研究

农业面源污染已成为中国首要环境问题,其污染范围广,污染后果严重.理清中国农业面源污染的地域分布规律,合理制定农业面源污染防控措施具有特别重要的意义.通过分析中国农业面源污染的形成途径,本文建立农业面源污染的评价指标,并利用该指标体系分析中国农业面源污染的空间分异规律,发现中国存在3类污染区域:农资污染区、畜禽污染区和水土流失型污染区,并针对不同区域,给出了政策建议.     

云南省农业面源污染及绿色发展途径

通过分析云南省发展现代农业带来的农田废水、畜禽粪便、农田固废的面源污染及其使得农业发展不可持续的问题,提出云南要实现生态文明,必须走有机农业道路,通过建立动物养殖-有机肥生产-沼气池处理污水-有机肥/沼液沼渣回用于有机种植的一体化循环产业模式可协同削减农田废水、畜禽粪便、农田固废的面源污染,并发挥其绿色发展效用。     

流域农业面源污染防治科学问题与技术研发需求

农业面源污染是当前我国面临的重要环境问题之一,也是影响我国水体环境质量持续改善的瓶颈.近年来,我国面源污染治理日益受到重视,相关治理管理体系逐步建立,但我国农业面源污染治理起步相对较晚、研究基础较薄弱.本文针对农业面源污染的现状及研究进展,总结提出了流域农业面源污染的三大科学问题及技术难题：流域面源污染发生规律及水体水质响应机制、农业面源污染削减和资源化原理、监管机制,并从农业面源污染通量监测、负荷核算、适用性技术研发、考核评估机制建立等方面提出了技术研发的需求,以期为我国流域农业面源污染防治及管理提供科学参考.     

农业面源污染防治措施进展研究

随着城市生活污水和工业废水等点源污染 得到控制,农业面源污染的危害日益凸显.将对目前的农业面源污染防治技术以及未来的发展进行阐述,将从源头减量、传输过程的阻断与拦截、养分的回收利用以及水体的生态修复面源污染物传输四个环节分别论述.源头控制主要采用减少化肥的施用量和水土流失等实现,传输过程的阻断与拦截以及养分的回收利用主要通过将径流引入人工或自然湿地等实现,水体的生态修复主要通过生态浮床技术等暂时强化技术与植物修复技术等长效修复技术相结合的方式实现.     

南水北调东线徐州段农业面源水污染控制的研究

南水北调东线徐州段区域农业面源水污染的防治措施包括:全面推动农村“一池三改”工程和生态处理设施建设;推动养殖小区的集中及规模化工程;大力推广新技术,实施测土配方施肥,建设生态农业示范区和面源减排示范区,发展生态农业;构建完整、有效的区域性面源等“多塘污染控制系统”.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

Toxic effects of acetochlor, methamidophos and their combination on nifH gene in soil

Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis （DGGE） and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity （both in gene richness and diversity index values） and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor （50 mg/kg） recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos （150 mg/kg） caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos （250 mg/kg） produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes （bands） responded differently to the impact of agrochemicals： four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

Arsenic uptake by arbuscular mycorrhizal maize （Zea mays L.） grown in an arsenic-contaminated soil with added phosphorus

The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Degradation of metabolites accumulated of benzo[a]pyrene by coupling Penicillium Chrysogenum with KMnO4

Several main metabolites of benzo[a]pyrene （BaP） formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone （BP 1,6- quinone）, trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene （BP 7,8-diol）, 3-hydroxybenzo[a]pyrene （3-OHBP）, were identified by high-performance liquid chromatography （HPLC）. The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that （1） the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; （2） the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; （3） the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% （w/v）, concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.     

Impact of atrazine and nitrogen fertilizers on the sorption of chlorotoluron in soil and model sorbents

Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.