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191.
清江流域自然旅游资源调查与评价方法   总被引:3,自引:2,他引:3  
根据清江流域自然旅游资源的特色,首先提出了一套对其进行详细系统的调查方法:(1)利用遥感数字图象处理技术及航、卫片解译结果,圈出潜在景区及潜在景点;(2)详细调查、收集及整理清江流域各市、镇已有资料,填写旅游资源调查登记卡片;(3)在(1),(2)基础上,对主要潜在景区及景点进行野外现场调研。然后,以调查结果为前提,提出了采用综合评分法,模糊数学评价方法,信息量评价方法,神经网络评价方法及地理信息  相似文献   
192.
水动力学法预测三峡工程对洞庭湖洲滩的影响   总被引:3,自引:1,他引:3  
用水动力学方法,根据三峡建库前后不同的时空边界条件,模拟长江水情要素,并建立长江水位与洞庭湖水位的回归方程,从而预测三峡工程对洞庭湖区洲滩面积的影响。  相似文献   
193.
在推进新型城镇化和生态建设的背景下,客观定量评价区域生态环境状态,是当前我国生态建设重要而紧迫的任务之一。高密度的人类活动会对自然生态系统产生超负荷的压力,通过生态承载力的分析能够定量测度这种状况,为区域可持续发展提供借鉴意义。基于生态足迹模型,计算了2008年和2013年武汉城市圈各县域单元的生态足迹/承载力,并进行了时空变化分析。研究发现武汉城市圈各县域单元的生态足迹和生态承载力在空间上存在显著的差异性,生态足迹逐年增加,生态承载力的变化相对较小,出现两级分化的现象。根据生态足迹/承载力进行跨区县生态补偿测算,得到2008年和2013年武汉城市圈48个县域的转移支付情况,表明如果运用财政转移支付的手段,整个区域能够达到生态系统供给和需求动态平衡的目标,缓解武汉城市圈的生态压力,实现武汉城市圈的可持续发展。  相似文献   
194.
Global climate change is one of the major environmental issues faced by humans.Existing evidence indicates that the anthropogenic push for a rise in the atmospheric concentration of greenhouse gases(GHGs)(particularly CO_2)has been a primary cause for global warming.Aside from economic and teclinological factors,demographic dynamics(including human consumption in a broad demographic sense)has been a major driver for CO_2 emissions.In this paper,we performed both nonlinear regression analysis(based on the STIRPAT model)and gray correlation degree analysis(based on gray system theory)on the impact of demographic dynamics on CO_2 emissions.Our results reveal that CO_2 emissions are positively correlated with population size and GDP per capita and negatively correlated with energy intensity.We also show that gray correlation degree with CO_2 emissions for five variables(i.e.,household consumption,urbanization rate,household size,population aging rate,population size)varies substantially:household consumptionurbanization ratehousehold sizepopulation aging ratepopulation size,with household consumption being the highest,and population size the lowest.To mitigate the impact of demographic dynamics on CO_2 emissions,it is of vital significance to nurture people's awareness of sustainable consumption and to adhere to current population control policies.  相似文献   
195.
A glasshouse pot experiment was conducted to study the effect of arbuscular mycorrhizal (AM) colonization by Glomus mosseae BEG167 on the yield and arsenate uptake of tomato plants in soil experimentally contaminated with five As levels (0, 25, 50, 75 and 150 mg kg(-1)). Mycorrhizal colonization (50-70% of root length) was little affected by As application and declined only in soil amended with 150 mg As kg(-1). Mycorrhizal colonization increased plant biomass at As application rates of 25, 50 and 75 mg kg(-1). Shoot As concentration increased with increasing As addition up to 50 mg kg(-1) but decreased with mycorrhizal colonization at As addition rates of 75 and 150 mg kg(-1). Shoot As uptake increased with mycorrhizal colonization at most As addition levels studied, but tended to decrease with addition of 150 mg As kg(-1). Total P uptake by mycorrhizal plants was elevated at As rates of 25, 50 and 75 mg kg(-1), and more P was allocated to the roots of mycorrhizal plants. Mycorrhizal plants had higher shoot and root P/As ratios at higher As application rates than did non-mycorrhizal controls. The soil of inoculated treatments had higher available As than uninoculated controls, and higher pH values at As addition levels of 25, 50 and 75 mg kg(-1). Mycorrhizal colonization may have increased plant resistance to potential As toxicity at the highest level of As contamination studied. Mycorrhizal tomato plants may have potential for phytoextraction of As from moderately contaminated soils or phytostabilization of more highly polluted sites.  相似文献   
196.
In order to efficiently remove volatile organic compounds (VOCs) from indoor air, onedimensional titanate nanotubes (TiNTs) were hydrothermally treated to prepare TiO2 nanocrystals with different crystalline phases, shapes and sizes. The influences of various acids such as CH3COOH, HNO3, HCl, HF and H2SO4 used in the treatment were separately compared to optimize the performance of the TiO2 nanocrystals. Comparedwith the strong and corrosive inorganic acids, CH3COOH was not only safer andmore environmentally friendly, but also more efficient in promoting the photocatalytic activity of the obtained TiO2. Itwasobserved that the anatase TiO2 synthesized in 15 mol/L CH3COOH solution exhibited the highest photodegradation rate of gaseous toluene (94%), exceeding that of P25 (44%) by a factor ofmore than two. The improved photocatalytic activity was attributed to the small crystallite size and surface modification by CH3COOH. The influence of relative humidity (20%-80%) on the performance of TiO2 nanocrystals was also studied. The anatase TiO2 synthesized in 15 mol/L CH3COOH solution was more tolerant tomoisture than the other TiO2 nanocrystals and P25.  相似文献   
197.
Environmental Science and Pollution Research - Microbial sulfate reduction, a vital mechanism for microorganisms living in anaerobic, sulfate-rich environments, is an essential aspect of the sulfur...  相似文献   
198.

Porous carbon is an excellent absorbent for pollutants in water. Here, we report a breakthrough in performance of porous carbon based on lignin prepared using sodium lignosulfonate (SLS), potassium carbonate and melamine as precursor, activator and nitrogen source, respectively. A series of characterization tests confirmed that in-situ nitrogen doping greatly enhanced porous structure, resulting in a specific surface area of 2567.9 m2 g?1 and total pore volume of 1.499 cm3 g?1, which is nearly twice that of non-nitrogen-doped porous carbon. Moreover, adsorption experiments revealed that at 303 K, the saturated adsorption capacity of chloramphenicol was as high as 713.7 mg g?1, corresponding to an improvement of 33.7%. Further, the prepared porous carbon exhibited a strong anti-interference against metal ions and humic acid. The adsorption process was confirmed to be an endothermic reaction dominated by physical adsorption, indicating that an increase in temperature is conducive to adsorption. The results of this study show that nitrogen-doped lignin-based porous carbon prepared by in-situ doping is a promising material to significantly alleviate water pollution owing to its low cost, excellent pore structure and good adsorption properties.

  相似文献   
199.
Chen  Yan  Su  Xuewei  Ma  Mingliang  Hou  Yongbo  Lu  Chenggang  Liu  Peizhe  Ma  Yong  Wan  Fei  Yang  Ying  Hu  Xinru  Yu  Zhenqi 《Environmental science and pollution research international》2022,29(58):87310-87318
Environmental Science and Pollution Research - In this work, the 3D magnetic flower-like Fe3O4@SiO2@Co3O4@BiOCl heterojunction photocatalyst was successfully prepared. The combination of BiOCl with...  相似文献   
200.
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