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1.
《环境保护科学》2015,(6):23-28
梳理了新丝绸之路经济带沿线区域经济社会环境现状,分析在当前中国"一带一路"发展战略指引下,新丝绸之路经济带环境保护面临的新形势、新问题,提出了为强化新丝绸之路经济带在开发过程中的环境保护,需要加大高功能水体及脆弱区保护力度、严格划定生态红线、加强战略规划环评、生态补偿及环境治理体系建设等对策建议。  相似文献   

2.
泉州近来频繁发生地质灾害,生态敏感程度较高,社会经济的发展受到了一定程度的制约.本文选取坡度、高程、坡向、水域、植被覆盖指数(NDVI)、土地利用类型6个生态因子,构建泉州市生态敏感性评价体系.通过ArcGIS平台结合层次分析法,对6个生态因子的敏感指数进行多因子综合评价,并运用自然断点法将结果划分为5个敏感等级.结果...  相似文献   

3.
本文以长沙市为例,从宏观的角度,根据旅游开发对旅游生态环境造成的影响程度,建立了长沙市旅游开发生态敏感度和旅游生态系统服务功能重要性的评价模型,在ArcGIS软件平台下构建了评价因子数据库并进行定量评价,最终从空间上对其旅游资源的生态功能分区进行综合评价。研究结果可为长沙市旅游环境保护、开发建设和分区管理提供参考依据,也可为类似区域旅游用地的生态功能分区评价提供借鉴。  相似文献   

4.
自然保护地体系是生态保护红线划定的基础。本文梳理了生态保护红线的概念及内涵演变,总结了我国自然保护地主要类型;按照保护地划定部门的标准及定义,将保护地或其功能区域中的核心区分为严格保护型、保护为主型、保护开发并重型三类,并建议将严格保护型、保护为主型两类保护地全域以及保护开发并重型保护地中的核心区域划入生态保护红线范畴内,以确保生态保护红线生态功能不降低、性质不改变、面积不减少。最后给出了生态保护红线中保护核心区域、缓冲区域等的保护建议。  相似文献   

5.
滨海湿地具有非常重要的生态服务功能,针对其独特的地理区位和资源特征,划定区域湿地生态保护红线,对于生态红线制度的落实和滨海湿地开发利用管理具有重要意义.本研究以黄河三角洲湿地为例,基于陆海统筹原则,建立滨海湿地区域生态保护红线区选划评价指标体系,采用GIS空间分析方法实现对湿地生态服务功能重要性和生态环境敏感/脆弱性的评价,划定黄河三角洲湿地生态保护红线范围,并提出分级管控要求.  相似文献   

6.
以沈阳市为例,为进一步在空间上识别沈阳市重要生态功能区域,明确生态环境保护的目标与重点,确保生态保护红线划定范围的科学准确,依据《生态保护红线划定指南》等技术规范要求,运用GIS空间分析与遥感影像解译技术结合沈阳市生态环境现状调查结果,对沈阳市不同生态功能类型区域进行了评价及等级、区域划分工作。结果表明,沈阳市自然生态系统生态功能以水源涵养功能、生物多样性维护功能、防风固沙功能为主,生态功能极重要区域3 652 km~2,占沈阳市国土总面积的28.4%。  相似文献   

7.
旅游度假资源保护性开发建设是国家生态文明建设的基本要求。以南京市国家级老山森林公园东区为研究对象,提供旅游度假区生态绿色发展的方向与对策。基于GIS空间分析,构建由地形地貌、土地利用、森林生态系统、湿地生态系统、生物多样性等5个要素组成的生态敏感评价指标体系,以30 m×30 m网格评价单元,开展单项因子和综合的生态敏感性评价。结果表明:研究区域生态敏感性整体上较高;单因子生态敏感评价中,土地利用结构和开发强度以及森林生态系统的林木斑块面积与数量对生态敏感程度的影响较为明显。综合生态敏感性评价中,极敏感区和高度敏感区共占研究区域面积的44.79%,中度敏感区约占17.20%,轻度敏感区和不敏感区各占17.16%和20.85%;极敏感区、高度敏感区分布在老山国家级森林公园的生态保育区和核心景观区域、老山南北山坡和山顶及佛手湖等水源涵养区域。构建开发与保护协调的空间格局,提出禁止、限制、管控和支撑5项对策建议。  相似文献   

8.
复杂地貌区域国土开发受生态环境因素影响较单一地貌地区更复杂,其境内生态敏感区类型较多,且空间分布比较杂乱,不同生态敏感区之间又相互影响。文章选择山、水、林、田、城互为镶嵌的广西钦州市作为案例城市,以小流域为评价单元,建立集"地"、"水"、"绿"三位于一体的评价体系,在遥感和GIS技术的支持下,将单因子定性分级和多因子空间叠加模型相结合,对整个区域的生态敏感区进行综合评价及分区。从研究结果来看,这种评价技术能够较好地反映这些生态敏感区的综合分异规律,有助于当地政府在区域开发中制定更为科学的生态安全防范对策。  相似文献   

9.
苏州市环境敏感地的划定研究   总被引:1,自引:0,他引:1  
工业化和城市化进程的迅猛推进促使人类开发与建设活动不断侵占坡地、优质农田等环境敏感地区,产生了众多生态环境问题,影响了区域可持续发展。针对不同类型区域的特点,对环境敏感地进行分类,划清区域未来开发与保护的界限,对实现区域健康发展具有重要的现实意义。论文从环境敏感地对经济发展的保障与支撑能力以及环境敏感地在苏州全市域生态功能保护区的重要性程度为出发点,将苏州市环境敏感地划分为生态功能敏感地、地表水源敏感地、污染影响敏感地、优质农田敏感地和潜在灾害敏感地5类,并进一步明确其空间分布范围,为苏州市建设用地扩张控制、资源管理、生态保护提供了理论依据。  相似文献   

10.
生态保护红线的划定对于维护国家和区域生态安全具有非常重要的作用,是我国在生态环境保护方面的重要举措.为分析生态保护红线划定后区域生态系统服务价值的变化情况,以重庆市两江新区为例,采用CLUE-S模型对未来的土地利用变化情况进行情景模拟,并在此基础上对各地类价值系数进行优化调整构建生态系统服务价值评估优化模型,对不同情景下的生态系统服务价值进行定量计算,分析生态系统服务价值的敏感度及变化度.结果表明:①采用CLUE-S模型对两江新区的未来土地利用进行空间模拟效果较好(Kappa系数达到0.82以上),模型的普适性较好.②生态价值敏感度结果表明两江新区的生态系统服务价值对价值系数的变化缺乏弹性,结果的可信度高.③2020年生态保护情景下,林地的面积增加量大于自然增长情景,城镇和工矿用地则相反,生态保护红线对于城镇扩张起到了一定的约束作用.④2014年现状、2020年自然增长情景和2020年生态保护情景下的生态系统服务价值分别约为10.53×108、10.50×108和10.88×108元,两种未来情景下耕地的生态系统服务价值减少最为明显,林地、水域服务价值均表现出增加的趋势.⑤林地和水域的生态价值变化度表明其面积变化对生态系统服务价值的影响较大.研究显示,CLUE-S模型进行小区域的土地利用变化情景模拟效果较好,构建的生态系统服务价值评估优化模型计算结果的可信度较高.政府相关部门可以根据生态保护红线及生态系统服务价值评估结果,进一步优化生活、生产和生态空间,使其在城市规划、绩效考核和生态补偿中得到实际运用,在区域的经济可持续发展中起到支撑作用.   相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
Decomposition of alachlor by ozonation and its mechanism   总被引:1,自引:0,他引:1  
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.  相似文献   

20.
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.  相似文献   

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