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101.
黄河口及邻近海域溶解态无机磷、有机磷、总磷的分布研究 总被引:3,自引:0,他引:3
于2003年8月下旬对黄河口及邻近海域进行了十船连续同步27h采样调查,分析了调查区域的溶解态无机磷、有机磷、总磷的平面分布、断面分布、时间分布特征.结果表明,在调查区域内,溶解态无机磷浓度很低,而溶解态有机磷浓度较高(占溶解态总磷的85%以上),是溶解态总磷的主要组成部分.各形态磷的平面分布、断面分布均呈现出由河口向邻近海域降低的趋势,溶解态总磷、溶解态有机磷梯度变化较溶解态无机磷更为明显;潮汐对河口浅水区的各形态磷浓度影响较大,对邻近调查海域的影响不明显. 相似文献
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文章采用铁屑一活性炭内电解法作为光合细菌生化处理染料废水的预处理方法,考查了3个主要影响因素(铁炭比、停留时间、初始pH值)。结果表明,最佳的处理条件为:铁炭比为7:3,pH值为5,停留时间为60min。在上述最佳处理条件下,对初始COD为6790mg/L的染料废水处理效率可以达到66.1%,并且废水经预处理后可生化性得到大大提高,有利于后续生化处理的进行。 相似文献
104.
Developing Canada's National Forest Carbon Monitoring, Accounting and Reporting System to Meet the Reporting Requirements of the Kyoto Protocol 总被引:2,自引:0,他引:2
The rate of carbon accumulation in the atmosphere can be reduced by decreasing emissions from the burning of fossil fuels
and by increasing the net uptake (or reducing the net loss) of carbon in terrestrial (and aquatic) ecosystems. The Kyoto Protocol
addresses both the release and uptake of carbon. Canada is developing a National Forest Carbon Monitoring, Accounting and
Reporting System in support of its international obligations to report greenhouse gas sources and sinks. This system employs
forest-inventory data, growth and yield information, and statistics on natural disturbances, management actions and land-use
change to estimate forest carbon stocks, changes in carbon stocks, and emissions of non-CO2 greenhouse gases. A key component of the system is the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS). The model
is undergoing extensive revisions to enable analyses at four spatial scales (national, provincial, forest management unit
and stand) and in annual time steps. The model and the supporting databases can be used to assess carbon-stock changes between
1990 and the present, and to predict future carbon-stock changes based on scenarios of future disturbance rates and management
actions. 相似文献
105.
Carbon Dioxide Balance of Wood Substitution: Comparing Concrete- and Wood-Framed Buildings 总被引:3,自引:0,他引:3
Leif Gustavsson Kim Pingoud Roger Sathre 《Mitigation and Adaptation Strategies for Global Change》2006,11(3):667-691
In this study a method is suggested to compare the net carbon dioxide (CO2) emission from the construction of concrete- and wood-framed buildings. The method is then applied to two buildings in Sweden
and Finland constructed with wood frames, compared with functionally equivalent buildings constructed with concrete frames.
Carbon accounting includes: emissions due to fossil fuel use in the production of building materials; the replacement of fossil
fuels by biomass residues from logging, wood processing, construction and demolition; carbon stock changes in forests and
buildings; and cement process reactions. The results show that wood-framed construction requires less energy, and emits less
CO2 to the atmosphere, than concrete-framed construction. The lifecycle emission difference between the wood- and concrete-framed
buildings ranges from 30 to 130 kg C per m2 of floor area. Hence, a net reduction of CO2 emission can be obtained by increasing the proportion of wood-based building materials, relative to concrete materials. The
benefits would be greatest if the biomass residues resulting from the production of the wood building materials were fully
used in energy supply systems. The carbon mitigation efficiency, expressed in terms of biomass used per unit of reduced carbon
emission, is considerably better if the wood is used to replace concrete building material than if the wood is used directly
as biofuel. 相似文献
106.
对废水污染源监测中影响监测数据代表性的主要因素进行了分析,并对提高废水污染源监测数据代表性提出了可行性建议。 相似文献
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110.
Can Forest-protection carbon projects improve rural livelihoods? Analysis of the Noel Kempff Mercado climate action project,Bolivia 总被引:1,自引:0,他引:1
Asquith Nigel M. Vargas Ríos María Teresa Smith Joyotee 《Mitigation and Adaptation Strategies for Global Change》2002,7(4):323-337
We studied the Noel KempffMercado Climate Action Project (NKMCAP),Bolivia, to assess whether forestprotection carbon (C) projects cansignificantly benefit local people. Wehypothesized that forest protection canonly securely deliver C if significantstakeholders are meaningfully andtransparently involved, traditional orcustomary rights are recognized and theirloss compensated for, and there are directlinkages between conservation anddevelopment objective. Our researchfocused on 53 members of the communities ofFlorida, Porvenir and Piso Firme and 36secondary stakeholders. In each of thevillages we held half-day meetings withcommunity leaders, complemented bysemi-structured one-hour interviews with 5,10, and 7 families, representing 20%, 10%and 8% of each community. The long-termimpact of the NKMCAP on the localcommunities may well be positive. However,in the short run, certain sections of thelocal communities are financially poorer. Forest protection projects clearly have thepotential to sequester C, protectbiodiversity and simultaneously contributeto sustainable rural development, but ifthey really are to improve rurallivelihoods, they must be designed andimplemented carefully and participatively. 相似文献