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排序方式: 共有662条查询结果,搜索用时 213 毫秒
1.
西藏农村能源消费及环境影响研究 总被引:5,自引:0,他引:5
西藏农村人口现有220多万,占全区总人口80%以上,农村经济落后,城乡差距很大。西藏农村能源资源主要有水力、地热、太阳能、风力、林木和畜粪等,煤炭、石油、天然气等高热值的优质能源很少。在这种经济发展水平及能源资源基础条件下,农村能源消费中高热值的现代能源比重很低,主要以生物质能如薪柴、牛粪、草皮等为主。这种低水平的能源消费结构已经对西藏脆弱的生态环境造成了巨大的破坏,西藏未来的能源发展战略迫切需要改变农村目前的消费结构,应发展太阳能、风能、农村小水电及输入高热值的化石能源替代目前生物质能的消费,减少因能源消费对西藏生态环境的破坏。 相似文献
2.
Volunteer monitoring of natural resources is promoted for its ability to increase public awareness, to provide valuable knowledge, and to encourage policy change that promotes ecosystem health. We used the case of volunteer macroinvertebrate monitoring (VMM) in streams to investigate whether the quality of data collected is correlated with data use and organizers' perception of whether they have achieved these outcomes. We examined the relation between site and group characteristics, data quality, data use, and perceived outcomes (education, social capital, and policy change). We found that group size and the degree to which citizen groups perform tasks on their own (rather than aided by professionals) positively correlated with the quality of data collected. Group size and number of years monitoring positively influenced whether a group used their data. While one might expect that groups committed to collecting good-quality data would be more likely to use it, there was no relation between data quality and data use, and no relation between data quality and perceived outcomes. More data use was, however, correlated with a group's feeling of connection to a network of engaged citizens and professionals. While VMM may hold promise for bringing citizens and scientists together to work on joint conservation agendas, our data illustrate that data quality does not correlate with a volunteer group's desire to use their data to promote regulatory change. Therefore, we encourage scientists and citizens alike to recognize this potential disconnect and strive to be explicit about the role of data in conservation efforts. 相似文献
3.
Toscas PJ 《Environmental monitoring and assessment》2008,137(1-3):379-385
Ammonia is an important water quality variable, which in excess, can be detrimental to waterways and their ecosystems. In
the Ecosystem Health Monitoring Program in South-east Queensland ammonia is monitored monthly, however, often more than 50%
of the ammonia observations in Moreton Bay are below detection limit, making it difficult to draw useful inferences. In this
paper a clipped Gaussian random field is used to spatially model and map the probability of detectable concentration of ammonia.
The methodology is applied to the Moreton Bay samples collected in February 2005. The results suggest that for this month
the oceanic impacted areas have higher probability of detectable ammonia concentration than the areas closer to the main sources
of anthropogenic inputs. 相似文献
4.
对环境监测中的数据、统计、有效数字、修约,以及计量单位、结果表达、原始数据的记录等既平常又十分重要易被忽略的重要问题作了概述,这些问题的解决才能保证监测结果的准确性和可靠性. 相似文献
5.
6.
我国土地资源利用的几个战略问题 总被引:4,自引:1,他引:4
我国人均资源占有量远低于世界水平,资源供应日益紧缺,并将成为经济发展的一个重要的约束条件。从土地资源的潜力来看,我国土地理论的最高人口承载量可能是15—16亿人,并在相当长的时期内将处于临界状态。关键在于控制人口的增长和在农业方面采取超常规的增产措施,特别是大幅度增加农业投入。我国土地生产潜力东部大于西部,粮食生产的重点应放在中部地带。20亿亩耕地是我国国土资源的精华所在,种植业的主攻方向应放在中产田,并大力加强我国九片商品粮基地的建设。林业建设的战略重点应尽快转向山区。牧业应发展饲料生产,开辟新的饲料基地。从总体看,应强调发展资源节约型的农业,以内涵挖潜为主,向生产的深度和广度进军。 相似文献
7.
建设项目审批数据管理系统的设计与实现 总被引:1,自引:0,他引:1
本系统根据葫芦岛市环境保护的需要,整合各种环境保护建设项目审批数据,建立Oracle数据仓库,利用PowerBuilder技术完成对环境保护建设项目数据的管理、统计与发布。 相似文献
8.
不同地域天然伊利石表面酸碱特性的比较 总被引:3,自引:2,他引:3
利用电位滴定技术和恒定容量表面络合模式表征不同来源天然伊利石的表面酸碱性质。鉴于固体基质在酸量滴定过程中发生溶解,相应的滴定上清液被视为体系空白。考虑到水解铝、硅酸和伊利石表面活性位之间的表面络合或沉淀反应,提出两种表面质子反应模型。对其中的特例,还考虑了表面离子交换反应。模拟程序的拟合结果显示两种模型对水解伊利石体系的滴定行为均可获得满意的描述。相的的表面固有酸度常数表明样品的酸碱性质之间存在一些共性。 相似文献
9.
《环境科学学报(英文版)》2023,35(4):174-183
It is the key to control bio-derived dissolved organic matters (DOM) in order to reduce the effluent concentration of wastewater treatment, especially for waste leachate with high organic contaminants. In the present study, the anaerobic degradation of aerobically stabilized DOM was investigated with DOM substrate isolated through electrodialysis. The degradation of bio-derived DOM was confirmed by reduction of 15% of total organic carbon in 100 days. We characterized the molecular behavior of bio-derived DOM by coupling molecular and biological information analysis. Venn based Sankey diagram of mass features showed the transformation of bio-derived DOM mass features. Occurrence frequency analysis divided mass features into six categories so as to distinguish the fates of intermediate metabolites and persistent compounds. Reactivity continuum model and machine learning technologies realized the semi-quantitative determination on the kinetics of DOM mass features in the form of pseudo-first order, and confirmed the reduction of inert mass features. Furthermore, network analysis statistically establish relationship between DOM mass features and microbes to identify the active microbes that are able to utilize bio-derived DOM. This work confirmed the biological technology is still effective in controlling recalcitrant bio-derived DOM during wastewater treatment. 相似文献
10.
根据对哈尔滨市所辖8区蔬菜生产基地土壤环境的调查和监测,利用土壤综合污染指数进行评价,哈尔滨市蔬菜生产基地土壤质量状况。 相似文献