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951.
在新的历史时期,对大学生进行艰苦奋斗精神的教育,是加强大学生思想道德建设的一项重要内容.本文通过对当代大学生艰苦奋斗精神弱化的主要表现,以及艰苦奋斗精神缺失原因的分析,指出加强当代大学生艰苦奋斗精神教育的对策,即着眼时代精神和现实意义,充实和改进艰苦奋斗教育的内容形式;加强主体性教育,增强学生自我教育和管理的能力;充分发挥校园文化的导向功能,积极营造崇尚节俭、鼓励奋斗的浓厚氛围.  相似文献   
952.
Abstract: Soil moisture is an important hydrological variable in reforestation practices in a water‐limited region of the Loess Plateau of northwestern China. The objective of this study was to quantify the spatial dynamics of soil moisture on a complex terrain. During 2004‐2006, a total of 313 sample points in two kinds of grid (2 × 2 m and 20 × 20 m) were arranged for soil moisture measurements (two soil layers: 0‐30 and 30‐60 cm) with Time Domain Reflectometry. The geostatistical properties of soil moisture patterns, the variance and correlation structure of the soil moisture, and the effects of terrain factors on soil moisture were analyzed. The results suggested that our sampling grid captured the spatial variability of soil moisture distributions for this complex terrain. Principal Component Analysis and Cluster Analysis statistics showed that soil moisture decreased as slope gradient increased; that sunny aspects (112.5°‐292.5°) had relatively lower soil moisture than did shady aspects (292.5°‐112.5°); that soil moisture was lowest in the SWW direction and highest in the NWN direction; and that hillslope aspect was the main factor affecting soil moisture in the 0‐ to 30‐cm soil layer, whereas the main factor for the 30‐ to 60‐cm layer was slope gradient. It was found that the relative values of soil moisture for steep slopes (>36%) with shady aspect (292.5°‐112.5°), gentle slopes (<36%) with sunny aspect (112.5°‐292.5°), and steep slopes with sunny aspect were 99, 82, and 80, respectively – assuming a soil moisture value of 100 for gentle slopes with shady aspect. The results of this study are expected to be relevant to and useful for reforestation planning and design, parameterization of distributed hydrology models, and land productivity assessment in the study region.  相似文献   
953.
Long-term dynamics of population decline can improve the conservation perspectives and strategies for endanger species. In China, new gazetteers having systematic compilation and wide geographical coverage can be considered as an important complementary for reconstruction historical distribution. For historical and cultural reasons, an endangered species–lynx (Lynx lynx) was recorded regularly in new gazetteers. Therefore, the aim of this paper was to evaluate the population distribution in Northeast China from the 1950s to 2014. The data show that Felis lynx was widely distributed in Northeast China in the 1950s, but the number of the occurrence records have been significantly reduced by 85.6% in the last 60 years. This research also enlightens us that the new gazetteers can contribute to data shortage and it would be helpful to conservation biology.  相似文献   
954.
Environmental Science and Pollution Research - The oily wastewater was treated by electrocoagulation with Fe78Si9B13 amorphous ribbons as anode and graphite plates as cathode under such processing...  相似文献   
955.
Environmental Science and Pollution Research - The solidification/stabilization (S/S) method is a common technique for the remediation of soils polluted by heavy metal. This study, thus, evaluated...  相似文献   
956.
Wang  Feng  Ren  Jing  Liu  Juan  Dong  Mingru  Yan  Bin  Zhao  Hui 《Environment, Development and Sustainability》2021,23(11):15881-15896

Based on relevant data from 2014 to 2018, we constructed a spatial network of haze pollution in the Pearl River Delta (PRD) region by using a modified gravity model, explored the network structure characteristics and influencing factors of urban agglomeration with the SNA and the QAP method, and discussed the population mobility effect brought by haze pollution. The results showed that the PRD region has spatial correlation in terms of haze pollution. Guangzhou was in the central position of the spatial network, yet Shenzhen and Foshan played a connecting role in the network. Economic development, urbanization, and environmental protection had significant positive impacts on the haze pollution spatial network. The results of the double-threshold regression showed that the city’s status in the haze pollution network represented by centrality had a positive impact on population mobility.

  相似文献   
957.
Environmental Science and Pollution Research - More and more scholars have paid attention to the importance of coordinated development between ecological environmental protection and economy....  相似文献   
958.
Environmental Science and Pollution Research - Amino sugars (AS) are routinely used as microbial biomarkers to investigate the dynamics of soil carbon (C) and nitrogen (N) under different...  相似文献   
959.
百年工业文明发展范式对自然环境的持续作用,使人类面临环境与发展的双重危机。生态文明具有内在统一性,环境法制是生态文明的应有之义。环境基本法是环境法制的基石,目的条款是环境基本法的元点。旧的目的条款沿袭工业文明发展范式,将发展经济奉为圭臬,始终无法调和人与自然的内在矛盾。修改环境基本法目的条款,融入生态文明因子具有自内而外、自外而内、自上而下以及自下而上四个方面的动力因素。  相似文献   
960.
基于结构化设计的湖、库富营养化模型研究   总被引:1,自引:0,他引:1  
任宏洋  张代钧  卢培利  许丹宇 《环境污染与防治》2005,27(5):371-374,381,i0004
基于结构化设计概念,将LEEDs模型与人工神经网络模型耦合,建立湖、库富营养化模型,模型包含N、P、COD、水温、水深和流速等6个控制模块。并以三峡水库为例预测结果表明,在3月和9~10月,月平均气温约为17℃,水深约为5m,流速约为0.02m/s时,三峡库区水体富营养化指标最大。模型具有可扩展性强,维护、升级容易等优点,可对模型中各个相对独立的模块进行调整,以适应不同湖库的实际情况。  相似文献   
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