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941.
从二氧化硫总量减排环保监督管理的实际出发,结合日常监督工作的实例,分析影响烟气脱硫效率的因素,找出脱硫系统容易出现的故障,提出对脱硫系统日常监督考核的重点,探索建立烟气脱硫系统监督考核方法。 相似文献
942.
通过野外实地调查,对辽宁省的4个国家级自然保护区外来入侵植物的种类数量和分布现状进行了调查分析。结果表明,老铁山、鸭绿江口、医巫闾山、九龙川4个自然保护区内的外来入侵植物分别为27,10,7和6种,总计16科36种。依据保护区内外来入侵植物的特点和生态影响,提出了一些有效的管理措施和防治建议。 相似文献
943.
RIP-N模型对官厅水库库滨带去氮效应的流域尺度模拟分析 总被引:1,自引:1,他引:0
以官厅水库库滨带为研究对象,构建适用于流域尺度岸边带去氮负荷估算的生态水文模型——RIP-N(Riparian-Nitrogen)模型,对官厅水库库滨带2007年3~9月间岸边带去氮效应进行分析.同时,在延庆水保站开展田间尺度的野外模拟实验,结合室内外试验分析和以往研究成果,对模型模拟结果进行验证.RIP-N模型包括土壤化学过程模拟和植物生长过程模拟.前者包括土壤反硝化模拟、硝化模拟和氨挥发模拟;后者包括植物净第一性生产力(net primary productivity,NPP)模拟、植物生产力分配模拟和植物营养元素吸收模拟.结果表明:①RIP-N模型模拟值与实验值的决定系数大于0.5,证明该模型在空间尺度模拟上的有效性及模拟结果的可靠性;②模型模拟结果表明官厅水库库滨带流域3~9月对N的总去除量为5.91×103t;③RIP-N模型对官厅水库库滨带去氮环境效益分析表明,当前库滨带土地利用格局中,滩地、林地和草地是去污效果较好的土地利用类型,3~9月对流域的去N量占流域总去N量的76.5%,在非点源污染防治中起到"汇"的作用;但是研究区中专属湿地的"汇"作用表现不明显,3~9月去N量仅占流域总去N量的5.9... 相似文献
944.
The rare plant Rheum palaestinum (Polygonaceae) is a perennial hemicryptophyte that grows during the rainy winter in desert mountainous areas in Israel and
Jordan that receive an average annual rainfall of ca. 75 mm. It produces between one and four large round leaves that are
tightly attached to the ground and form large rosettes of up to 1 m2. These leaves differ markedly from the typical small leaves of most desert plants. Moreover, they have a unique 3D morphology
resembling a scaled-down mountainous area with well-developed steep drainage systems, raising the question which selective
agents were involved in their evolution. We propose that the large leaves collect rainwater that then infiltrates the soil
surrounding the root. We measured the seasonal course of leaf growth, examined the area of wet soil surrounding the root after
actual and simulated rain, and modeled the water harvesting capacity using the plant leaf area and the weekly precipitation.
We show that even in the slightest rains, water flows above the veins to the leaf’s base where it irrigates the vertical root.
A typical plant harvests more than 4,100 cm3 of water per year, and enjoys a water regime of about 427 mm/year, equivalent to the water supply in a Mediterranean climate.
This is the first example of self-irrigation by large leaves in a desert plant, creating a leaf-made mini oasis.
All authors contributed equally to this paper. 相似文献
945.
946.
A mesocosm experiment was conducted to investigate whether plant coexistence affects cadmium (Cd) uptake by plant in contaminated soil.Tobacco (Nicotiana tabacum L.var.K326) and Japanese clover (Kummerowia striata (Thunb.) Schindl.) were used.Cadmium was applied as 3CdSO 4 ·8H 2 O in solution at three levels (0,1,and 3 mg/kg soil) to simulate an unpolluted soil and soils that were slightly and moderately polluted with Cd.Tobacco (crop),Japanese clover (non-crop),and their combination were grown under each C... 相似文献
947.
The mercury removals by existing pollution control devices in four coal-fired power plants of China were carried out based on a measurement method with the aluminum matrix sorbent. 相似文献
948.
Kanyanee Seangkiatiyuth Vanisa Surapipith Kraichat Tantrakarnap Anchaleeporn W. Lothongkum 《环境科学学报(英文版)》2011,23(6):931-940
We applied the model of American Meteorological Society-Environmental Protection Agency Regulatory Model (AERMOD) as a
tool for the analysis of nitrogen dioxide (NO2) emissions from a cement complex as a part of the environmental impact assessment. The
dispersion of NO2 from four cement plants within the selected cement complex were investigated both by measurement and AERMOD
simulation in dry and wet seasons. Simulated values of NO2 emissions were compared with those obtained during a 7-day continuous
measurement campaign at 12 receptors. It was predicted that NO2 concentration peaks were found more within 1 to 5 km, where the
measurement and simulation were in good agreement, than at the receptors 5 km further away from the reference point. The Quantile-
Quantile plots of NO2 concentrations in dry season were mostly fitted to the middle line compared to those in wet season. This can be
attributed to high NO2 wet deposition. The results show that for both the measurement and the simulation using the AERMOD, NO2
concentrations do not exceed the NO2 concentration limit set by the National Ambient Air Quality Standards (NAAQS) of Thailand.
This indicates that NO2 emissions from the cement complex have no significant impact on nearby communities. It can be concluded
that the AERMOD can provide useful information to identify high pollution impact areas for the EIA guidelines. 相似文献
949.
文章研究了凤眼莲、轮叶黑藻、香根草和水蕹菜四种水生植物在亚热带气候条件下净化水产养殖废水的效果,跟踪比较了一个月之内它们处理污水时,水体氮、磷、化学需氧量、pH值和溶解氧的变化,并对实验前后植物鲜重做了比较。结果表明:(1)4种植物均能强化水产养殖废水污染物的去除,但各有特点;(2)理论上凤眼莲和轮叶黑藻可在处理废水时相互搭配弥补不足,维持水体中性和较高的DO;(3)植物对废水经过2~3周的处理后,水质明显变好,而植物生长开始减退,应及时收割补种;(4)夏季用水生蕹菜处理废水,不仅改善了水质还能收菜创经济效益。研究结果为探索广东地区在构建人工湿地处理水产养殖废水时植物的选择提供了新的科学依据。 相似文献
950.
运用超声提取、氧化铝-硅胶组合填料层析净化、气相色谱-质谱联用(GC-MS)检测,建立了设施番茄植株根、茎、叶和果实中同时测定百菌清和毒死蜱含量的分析方法。针对设施番茄植株叶绿素含量高的特点,优化了层析柱填料和洗脱溶剂配比,并研究了两种农药在层析柱中的洗脱规律。结果表明,在番茄根、茎、叶和果实中,百菌清平均回收率分别为... 相似文献