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71.
72.
Soil organic carbon decomposition and carbon pools in temperate and sub-tropical forests in China 总被引:2,自引:0,他引:2
Yang L Pan J Shao Y Chen JM Ju WM Shi X Yuan S 《Journal of environmental management》2007,85(3):690-695
Decomposition of soil organic carbon (SOC) is a critical component of the global carbon cycle, and accurate estimates of SOC decomposition are important for forest carbon modeling and ultimately for decision making relative to carbon sequestration and mitigation of global climate change. We determined the major pools of SOC in four sites representing major forest types in China: temperate forests at Changbai Mountain (CBM) and Qilian Mountain (QLM), and sub-tropical forests at Yujiang (YJ) and Liping (LP) counties. A 90-day laboratory incubation was conducted to measure CO(2) evolution from forest soils from each site, and data from the incubation study were fitted to a three-pool first-order model that separated mineralizable soil organic carbon into active (C(a)), slow (C(s)) and resistant (C(r)) carbon pools. Results indicate that: (1) the rate of SOC decomposition in the sub-tropical zone was faster than that in the temperature zone, (2) The C(a) pool comprised approximately 1-3% of SOC with an average mean residence time (MRT) of 219 days. The C(s) pool comprised approximately 25-65% with an average MRT of 78 yr. The C(r) pool accounted for approximately 35-80% of SOC, (3) The YJ site in the sub-tropical zone had the greatest C(a) pool and the lowest MRT, while the QLM in the temperature zone had the greatest MRT for both the C(a) and C(s) pools. The results suggest a higher capacity for long-term C sequestration as SOC in temperature forests than in sub-tropical forests. 相似文献
73.
Methods for determination of minimum pool levels in reservoirs that consider sport fishery values are being sought by managers.
We developed a technique for assessing the effects of incremental changes in minimum pool levels on potential salmonid abundance
in small (<100 surface hectares at full pool) reservoirs in Wyoming managed for irrigation and municipal water supplies. The
method has two components. One component is used to determine the minimum pool level needed to eliminate the risk of overwinter
loss of salmonids due to low dissolved oxygen concentrations. The other component predicts the potential biomass of salmonids
in reservoirs as a function of water depth and total dissolved solids concentration of the reservoir water. Application of
the method is demonstrated for two reservoirs in Wyoming.
The unit is jointly supported by the University of Wyoming, the Wyoming Game and Fish Department, and the US Fish and Wildlife
Service. 相似文献
74.
含氯化亚铁添加剂细水雾灭火有效性的实验研究 总被引:8,自引:2,他引:8
为了提高常规细水雾的灭火有效性,拓展其应用范围,本文采用小尺度实验的方法,研究了含氯化亚铁添加剂细水雾在不同燃料种类、添加剂浓度、压力下扑灭池火的有效性。实验结果表明:向细水雾中添加氯化亚铁,显著地影响了它的灭火性能;细水雾的灭火时间随着加入的氯化亚铁的质量浓度变化而发生改变,而且存在一个最短灭火时间浓度;细水雾喷头的工作压力和燃料的类型也对细水雾的灭火性能有影响,喷头工作压力越大,细水雾的平均灭火时间越短;在相同的实验条件下,细水雾灭煤油火的时间要短于灭乙醇火的时间。 相似文献
75.
Troubles on the way: An analysis of the challenges faced by multi-stakeholder platforms 总被引:2,自引:0,他引:2
Nicolas Faysse 《Natural resources forum》2006,30(3):219-229
Multi‐stakeholder platforms (MSPs) have been widely promoted as a promising means of resolving conflicts over natural resources, first in developed countries and, more recently, as a global good practice. However, many MSPs have been implemented in an unfavourable context — primarily of social inequities — and have not met initial high expectations. The article analyzes the challenges MSPs face in an unfavourable context, and identifies five main issues:
- ? Power relationships;
- ? Platform composition;
- ? Stakeholder representation and capacity to participate meaningfully in the debates;
- ? Decision‐making power and mechanisms; and finally
- ? Cost of setting up an MSP.
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张瑜 《再生资源与循环经济》2020,(2):34-37
为截流和处理某市内河的外来污染源,河道综合整治工程是某市内河水系底泥污染系统综合开发工程的重要工程之一,主要内容包括:河道工程、截污工程、底泥疏浚、景观工程等。截污工程采取“沿河截污,超量溢流”的工程方案沿河敷设截污管道,并在河道交汇处设置合流污水调蓄池。 相似文献
80.
化工储罐区空袭次生灾害危险性评价研究 总被引:1,自引:0,他引:1
根据化工储罐区及其遭空袭次生灾害的特点,以空袭次生灾害的影响范围作为危险性评价的标准,对化工储罐区的空袭次生灾害进行危险性评价。指出储罐遭空袭后的3种毁伤方式;给出储罐遭空袭发生的次生灾害及其扩散的形式与后果;阐述了化工储罐区空袭次生灾害的成灾机理;分别提出热辐射伤害、冲击波伤害和有毒有害物质扩散的危险性评价方法。以池火灾为例,建立了池火灾的危险性评价模型;论述了池火灾危险性评价的具体流程,并进行了案例分析,根据计算结果提出了相应的减灾对策。笔者认为,化工储罐区遭空袭后的次生灾害的危险性评价具有现实意义,对于化工园区、石化厂、危化品仓库等突发安全事故产生次生灾害的危险性评价同样具有重要的参考价值。 相似文献