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911.
生态意识变迁的考察与草地畜牧业可持续发展--以内蒙古锡林郭勒退化草地为例 总被引:8,自引:0,他引:8
目前,内蒙古草地生态环境破坏严重。且总体上呈不断恶化的态势。这种状况的持续不仅严重影响和翻约着本地区经济和社会的总体发展。同时也威胁着包括北京在内的整个华北地区的生态安全。其内在的深层次的根源就在于包括生态意识在内的人们的文化价值观发生了“扭曲”。本文针对锡林郭勒退化草地现状与历史的分析.揭示了其中的文化特征与哲学内涵.并且指出生态意识的确立和生态文化的形成对于保护草地、建设草地的现实意义。 相似文献
912.
Chengzhi Xing Cheng Liu Qihou Hu Qingyan Fu Shanshan Wang Hua Lin Yizhi Zhu Shuntian Wang Weiwei Wang Zeeshan Jave Xiangguang Ji Jianguo Liu 《环境科学学报(英文版)》2021,33(7):44-55
Ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations were operated from 02 to 21 December 2018 in Leshan, southwest China, to measure HONO, NO2 and aerosol extinction vertical distributions, and these were the first MAX-DOAS measurement results in Sichuan Basin. During the measurement period, characteristic ranges for surface concentration were found to be 0.26–4.58 km?1 and averaged at 0.93 km?1 for aerosol extinction, 0.49 to 35.2 ppb and averaged at 4.57 ppb for NO2 and 0.03 to 7.38 ppb and averaged at 1.05 ppb for HONO. Moreover, vertical profiles of aerosol, NO2 and HONO were retrieved from MAX-DOAS measurements using the Heidelberg Profile (HEIPRO) algorithm. By analysing the vertical gradients of pollutants and meteorological information, we found that aerosol and HONO are strongly localised, while NO2 is mainly transmitted from the north direction (city center direction). Nitrogen oxides such as HONO and NO2 are important for the production of hydroxyl radical (OH) and oxidative capacity in the troposphere. In this study, the averaged value of OH production rate from HONO is about 0.63 ppb/hr and maximum value of ratio between OH production from HONO and from (HONO+O3) is > 93% before12:00 in Leshan. In addition, combustion emission contributes to 26% for the source of HONO in Leshan, and we found that more NO2 being converted to HONO under the conditions with high aerosol extinction coefficient and high relative humidity is also a dominant factor for the secondary produce of HONO. 相似文献
913.
Differences in sensitivity to the fungal pathogen Batrachochytrium dendrobatidis among amphibian populations 下载免费PDF全文
Paul W. Bradley Stephanie S. Gervasi Jessica Hua Rickey D. Cothran Rick A. Relyea Deanna H. Olson Andrew R. Blaustein 《Conservation biology》2015,29(5):1347-1356
Contributing to the worldwide biodiversity crisis are emerging infectious diseases, which can lead to extirpations and extinctions of hosts. For example, the infectious fungal pathogen Batrachochytrium dendrobatidis (Bd) is associated with worldwide amphibian population declines and extinctions. Sensitivity to Bd varies with species, season, and life stage. However, there is little information on whether sensitivity to Bd differs among populations, which is essential for understanding Bd‐infection dynamics and for formulating conservation strategies. We experimentally investigated intraspecific differences in host sensitivity to Bd across 10 populations of wood frogs (Lithobates sylvaticus) raised from eggs to metamorphosis. We exposed the post‐metamorphic wood frogs to Bd and monitored survival for 30 days under controlled laboratory conditions. Populations differed in overall survival and mortality rate. Infection load also differed among populations but was not correlated with population differences in risk of mortality. Such population‐level variation in sensitivity to Bd may result in reservoir populations that may be a source for the transmission of Bd to other sensitive populations or species. Alternatively, remnant populations that are less sensitive to Bd could serve as sources for recolonization after epidemic events. 相似文献
914.
N-nitrosamines are characterized with an N-nitroso group N–NO. N-nitrosamines are strong carcinogens or potent carcinogens. Nitrosamines occur widely in the environment, e.g., as tobacco smoke that causes cancers of lungs, larynx, oral cavity and pharynx, pancreas, kidney and bladder. It is difficult to capture selectively N-nitrosamines in the environment. Therefore, zeolite, which is a molecular sieve, may help to sequester N-nitrosamines. Zeolites are a class of aluminosilicates, characterized by ordered microporous structures with acidic–basic sites on the surface and energetic field inside the pores. They have been widely applied in industry as adsorbents and catalysts because of their unique shape selectivity. Here, we review the latest research on adsorption and catalytic degradation of N-nitrosamines by zeolite materials. The efficiency of zeolite is increased using metal oxides. Removal of N-nitrosamines in smoke is discussed. 相似文献
915.
916.
啤酒废酵母的综合利用 总被引:6,自引:0,他引:6
啤酒废酵母含有丰富的营养物质,许多啤酒厂并没有充分利用,而是作为废弃物排入啤酒废水,增加了啤酒废水的处理负荷和难度。针对这种情况,我们利用本厂啤酒废酵母进行了生产酵母抽提物及营养酱油的研究,取得了满意的效果。不仅获得了优质产品,而且大大降低了啤酒酵母的污染负荷。 相似文献
917.
室内空气污染与人体健康关系探讨 总被引:4,自引:0,他引:4
阐述了室内空气污染的定义、种类、来源,国内外研究现状。分析了燃烧产物、被动吸烟,VOC、甲醛,氡及其子体,室内微生物对人体健康的危害。探讨了白血病、“大楼综合症”与室内空气污染的关系。指出由于我国建筑装修(饰)行业管理不到位,法律,法规不健全,建材质量在整体上落后,未能与经济的高速发展同步。且存在严重的地方保护和有法不依,执法不严的现象,使得室内空气污染问题突出,对人体健康造成了很大的危害。提出了严格我国室内空气质量标准的建议。 相似文献
918.
沸石曝气生物滤池去除氨氮性能及生物学特征分析 总被引:12,自引:0,他引:12
天然沸石具有较大的孔隙率和比表面积,对氨氮有较强的选择性离子交换能力。运用天然沸石曝气生物滤池处理城市污水厂二级生化出水,结果表明,曝气生物滤池有良好的去除效果。在气水比为3:1,水力负荷为1m/h,温度>20℃情况下,沸石曝气生物滤池对城市污水厂二级生化出水COD去除率为12.7%,NH3-N去除率为96.6%;试验系统沿程微生物活性和微生物量呈现逐渐下降趋势,而单位生物量的生物活性沿程分布则与此相反;曝气生物滤池对水中污染物的去除主要集中在底部进水端部分,当水流达到距进水端上方105cm时,曝气生物滤池对水中NH3-N的去除率已达86.8%(占氨氮总去除率的90%),COD的去除率为13.3%(占COD总去除率的67%)。 相似文献
919.
Liu Wei Zhou Yongxian Hua Yinfeng Peng Bin Deng Mei Yan Naiqiang Qu Zan 《Environmental science and pollution research international》2019,26(24):24831-24839
Environmental Science and Pollution Research - Adsorption is a typical method for air pollutant removal from flue gas. A CuS-modified active coke (CuS/AC) sorbent was developed to improve the... 相似文献
920.
Zhao Xinxin Yang Hua Li Ruishan Cui Ziming Liu Xueqin 《Environmental science and pollution research international》2019,26(6):5524-5538
Environmental Science and Pollution Research - Facilitating the separation of photogenerated electron/hole pairs and widening the light-responsive region are crucial to enhance the overall... 相似文献