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991.
山东省自然保护区管理状况调查与分析 总被引:1,自引:0,他引:1
基于自然保护区管理机构、人员配置、固定资产、事业经费、基建与生态工程投入、旅游收入等17项调查指标,系统调查了山东省自然保护区管理机构、人员配置和资金投入状况,定量分析了山东省自然保护区管理状况,论述了自然保护区管理存在的主要问题与对策。结果表明:山东省56%的自然保护区建立了专门的管理机构,63%的自然保护区现有人员数量低于25人,33%的自然保护区事业经费低于45万元。自然保护区管理存在的主要问题是管理机构不健全、人员配置不合理和资金投入不足。因此,山东省自然保护区管理应进一步完善管理机构,合理配置人员,增加资金投入。 相似文献
992.
生物炭因具有较大的孔隙度、比表面积以及较强的吸附能力等优点,在环境污染修复、土壤改良和固碳方面应用广泛.由于大多数生物炭表面带有负电荷,而土壤中的无机砷主要以砷酸盐和亚砷酸盐等阴离子形式存在.因此,生物炭对砷的吸附效率通常较低,需要对生物炭进行改性以提升其对砷的吸附效果.零价铁和氧化铁等铁基材料对砷吸附能力强且来源广泛,通过沉淀法、热解法、球磨法和微生物法等方法将铁基材料与生物炭负载形成铁修饰生物炭,可将二者的优良特性相结合,拓展生物炭材料在环境修复中的应用.在对近年来有关铁修饰生物炭的文献进行系统分析的基础上,综述了常见的铁修饰生物炭的制备方法,比较分析了生物炭基底、铁修饰材料以及两者对砷的协同作用机制,并简要阐述了铁修饰生物炭在土壤污染修复中的应用现状,最后对铁修饰生物炭的未来研究方向提出了展望. 相似文献
993.
近年来,许多学者利用现场地震监测或数值试验来研究斜坡的地震响应,然而不同斜坡往往存在不同类型的地貌单元,其动力响应机制往往也存在很大差异。本文依托海原大地震区域,基于室内试验、现场波速测试等方法,运用有限元数值模拟技术对海原大地震影响范围内不同地貌单元的斜坡的动力响应进行了研究。结果表明:黄土塬具有高程放大效应,在同一高程水平面上,且距坡面一定范围内时越趋近坡面斜坡动力放大系数(peak ground acceleration amplification coefficient,PGA放大系数)越大;对比不同类型的地貌单元,地层结构相同的斜坡其响应规律一致,但在古土壤层其PGA放大效应会减弱。模型分析较好地揭示了人工合成地震波作用下黄土高原斜坡的动力放大效应,可为不同地貌单元地震诱发的地质灾害的风险评价和防灾减灾提供有益的借鉴与参考。 相似文献
994.
以机动车碳排放模型为基础,结合不同类型机动车存活曲线,建立分车龄的车队构成,并利用年均行驶里程和燃油消耗量,分析了京津冀地区2005~2020年道路碳排放量的演变及区域分布特征.结果显示,河北省道路碳排放量增长迅速,近5a仍以7.14%的年均增长率快速增长,而北京和天津两市的道路碳排放已经进入低速增长期,近5a的年均增长率分别仅为1.01%和2.27%.小型客车一直都是道路碳排放的主力车型,其碳排放量占京津冀道路碳排放总量50%以上;轻型货车在北京市道路碳排放中的贡献越来越突出,而河北和天津两地轻型和重型货车正在逐渐发展为道路碳排放增长的主要驱动因素.从京津冀道路碳排放的4km×4km网格分布图可知,因北京和天津拥有更密集的道路,其碳排放强度远高于河北省. 相似文献
995.
Jianfeng Zhang Shichang Wei Zhenxing Liu Huang Tang Xiaoguang Meng Weihuang Zhu 《环境科学学报(英文版)》2022,34(8):67-75
In this study, Pb(II) was used as a target heavy metal pollutant, and the metabolism of Shewanella putrefaciens (S. putrefaciens) was applied to achieve reducing conditions to study the effect of microbial reduction on lead that was preadsorbed on graphene oxide (GO) surfaces. The results showed that GO was transformed to its reduced form (r-GO) by bacteria, and this process induced the release of Pb(II) adsorbed on the GO surfaces. After 72 hr of exposure in an S. putrefaciens system, 5.76% of the total adsorbed Pb(II) was stably dispersed in solution in the form of a Pb(II)-extracellular polymer substance (EPS) complex, while another portion of Pb(II) released from GO-Pb(II) was observed as lead phosphate hydroxide (Pb10(PO4)6(OH)2) precipitates or adsorbed species on the surface of the cell. Additionally, increasing pH induced the stripping of oxidative debris (OD) and elevated the content of dispersible Pb(II) in aqueous solution under the conditions of S. putrefaciens metabolism. These research results provide valuable information regarding the migration of heavy metals adsorbed on GO under reducing conditions due to microbial metabolism. 相似文献
996.
对2015—2016年盐城市城区4个空气质量自动监测国控站点的O_3监测数据进行分析,探讨盐城市O_3污染水平、时空分布特征及其与前体物、气象因子之间的关系。结果表明,各站点O_3污染水平较为接近,2016年各站点O_3-8h第90百分位数超标天数较2015年分别下降了43.5%,50.0%,8.7%和43.6%;全年O_3逐月值大致呈双峰分布,高ρ(O_3)主要集中在4—10月;O_3日变化曲线呈明显的单峰分布,一般在05:00—07:00最低,13:00—15:00达到峰值;不同季节的O_3日变化情况有所差异,午后O_3峰值与O_3日变化幅度均在春季最大,冬季最低;NO、NO_2和CO的日变化曲线均呈现出早晚双峰分布,受早高峰影响,一般在07:00左右达到一日中的最大值;O_3与NO_x等前体物均显著负相关,高ρ(O_3)往往出现在高ρ(CO)/ρ(NO_2)时;总体上各站点的ρ(O_3)随风速的增大而增大。 相似文献
997.
Sulfur deposition simulations over China, Japan, and Korea: a model intercomparison study for abating sulfur emission 总被引:1,自引:1,他引:0
Cheol-Hee Kim Lim-Seok Chang Fan Meng Mizuo Kajino Hiromasa Ueda Yuanhang Zhang Hye-Young Son Jong-Jae Lee Youjiang He Jun Xu Keiichi Sato Tatsuya Sakurai Zhiwei Han Lei Duan Jeong-Soo Kim Suk-Jo Lee Chang-Keun Song Soo-Jin Ban Shang-Gyoo Shim Young Sunwoo Tae-Young Lee 《Environmental science and pollution research international》2012,19(9):4073-4089
In response to increasing trends in sulfur deposition in Northeast Asia, three countries in the region (China, Japan, and Korea) agreed to devise abatement strategies. The concepts of critical loads and source?Creceptor (S?CR) relationships provide guidance for formulating such strategies. Based on the Long-range Transboundary Air Pollutants in Northeast Asia (LTP) project, this study analyzes sulfur deposition data in order to optimize acidic loads over the three countries. The three groups involved in this study carried out a full year (2002) of sulfur deposition modeling over the geographic region spanning the three countries, using three air quality models: MM5-CMAQ, MM5-RAQM, and RAMS-CADM, employed by Chinese, Japanese, and Korean modeling groups, respectively. Each model employed its own meteorological numerical model and model parameters. Only the emission rates for SO2 and NOx obtained from the LTP project were the common parameter used in the three models. Three models revealed some bias from dry to wet deposition, particularly the latter because of the bias in annual precipitation. This finding points to the need for further sensitivity tests of the wet removal rates in association with underlying cloud?Cprecipitation physics and parameterizations. Despite this bias, the annual total (dry plus wet) sulfur deposition predicted by the models were surprisingly very similar. The ensemble average annual total deposition was 7,203.6?±?370 kt S with a minimal mean fractional error (MFE) of 8.95?±?5.24?% and a pattern correlation (PC) of 0.89?C0.93 between the models. This exercise revealed that despite rather poor error scores in comparison with observations, these consistent total deposition values across the three models, based on LTP group's input data assumptions, suggest a plausible S?CR relationship that can be applied to the next task of designing cost-effective emission abatement strategies. 相似文献
998.
Wang Jiajun Meng Xiaoqing Chen Yu Zheng Guanyu Zhou Lixiang 《Environmental science and pollution research international》2021,28(11):13300-13311
Environmental Science and Pollution Research - Fenton conditioning processes have been recently employed to improve the dewaterability of sewage sludge. However, it remains unclear whether the... 相似文献
999.
Shanshan Zhao Zhu Tao Liwei Chen Muqiao Han Bin Zhao Xuelin Tian Liang Wang Fangang Meng 《Frontiers of Environmental Science & Engineering》2021,15(4):63
1000.
Mengmeng Guo Guanchao Zheng Jixing Peng Di Meng Haiyan Wu 《Journal of environmental science and health. Part. B》2019,54(4):271-280
Perfluorinated alkyl substances (PFASs) are emerging persistent organic pollutants, which pose a threat to human health primarily by dietary exposure, especially through seafood. Bohai Sea (a semi-closed sea located north of China) is an important shellfish aquaculture area that is possibly highly-polluted with PFASs. In this study, we first evaluated contamination by PFASs in a total of 230 samples of marine shellfish from the Bohai Sea. Samples included five important shellfish species, collected from important aquaculture spots distributed around the Bohai Sea. Samples were analyzed by an ultra-fast liquid chromatography-tandem mass spectrometry method, which could simultaneously detect 23 PFASs in shellfish. Our research verified that PFASs have become a threat to the safety of shellfish products in this area. Furthermore, contamination by PFASs in shellfish changed depending on the components of PFASs, the species of shellfish, and the sampling sites. Many of the 23 target compounds contributed to the high detection ratio (>50%) as follows: perfluorooctanoic acid (PFOA)?>?perfluorononanoic acid?>?perfluorodecanesulfonic acid?>?perfluorooctanesulfonic acid (PFOS). Compared with other dominant components, PFOA not only had the highest detection percentage in shellfish samples (98.3%), but its detection level contributed to 87.2% of total PFASs concentrations, indicating that PFOA is the major threat to the safety of shellfish products. The highest level of PFAS was found in clams (62.5?ng?g?1 wet weight of PFOA). The concentration of total PFAS in different shellfish species showed the following trend: clams?>?mussels?>?scallops?>?whelks?>?oysters. The maximum concentration of total PFAS or PFOA was found in Shouguang. The total concentration of PFOS and its precursor were highest in Cangzhou, possibly due to local industrial activities. The results presented in this paper provide new data on the contamination of marine shellfish along the Bohai Sea coasts in China, and constitute a reference for future monitoring of contamination by emerging contaminants in Bohai coast. 相似文献