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51.
Stockmann KD Anderson NM Skog KE Healey SP Loeffler DR Jones G Morrison JF 《Carbon balance and management》2012,7(1):1
Background
Global forests capture and store significant amounts of CO2 through photosynthesis. When carbon is removed from forests through harvest, a portion of the harvested carbon is stored in wood products, often for many decades. The United States Forest Service (USFS) and other agencies are interested in accurately accounting for carbon flux associated with harvested wood products (HWP) to meet greenhouse gas monitoring commitments and climate change adaptation and mitigation objectives. This paper uses the Intergovernmental Panel on Climate Change (IPCC) production accounting approach and the California Forest Project Protocol (CFPP) to estimate HWP carbon storage from 1906 to 2010 for the USFS Northern Region, which includes forests in northern Idaho, Montana, South Dakota, and eastern Washington. 相似文献52.
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高分辨率层序地层学——创新,应用及发展前景 总被引：4，自引：0，他引：4
高分辨率层序地层学的研究有了巨大的发展，其主要有两个方面的应用，一是全球海平面变化曲线的建立和对比，二是等时性剖面中的岩性特征预测。研究表明，沉积学、生物地层学、构造地质学及地震学等证据的结构，对提高分辨率层序地层学的解释水平是十分必要的。文集收集的论文反映了当代层序地层学研究的深度和广度。 相似文献
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本文阐述了澳大利亚解决水资源系统的不确定性的新进展。澳大利亚的降雨和径流非常高的易变意味着气候的简单变化可能扩大先前已存在的问题。考虑了流量的易变性对城市、灌溉及环境用水的影响，以及日益增加的大暴雨可能性的基础问题。通常情况下，对径流分配和需求管理，提高业务的主要方面是水资源随机可利用性，而不是它的绝对数量。由于易变性而强加的约束限制，运行规则允许采用分散决策。这允许独立的代理人表达他们的风险选择 相似文献
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我们于１９９１年３月在安大略湖上开展了航空重力测量，实施这一测量的目的，是要对采用小型飞机开展航空重力观测这种方便快速、价格低廉的测量方法进行可行性研究。本次所采遥仪器为拉柯斯特－降贝尔格线性动态重力仪，并装备有数字控制器的Ｌａｐ－ｔｏｐ型微机。这套设备安装在引擎ＰｉｐｅｒＮａｖａｊｏ飞机上。在邻近的基点上采用天宝４０００型ＧＰＳ接收机采集信号，并选择差分工作形式提供精确的定位数据，在飞机上则使用 相似文献
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Naturally occurring long-term mean annual recharge to ground water in Nebraska was estimated by a novel water-balance approach. This approach uses geographic information systems (GIS) layers of land cover, elevation of land and ground water surfaces, base recharge, and the recharge potential in combination with monthly climatic data. Long-term mean recharge > 140 mm per year was estimated in eastern Nebraska, having the highest annual precipitation rates within the state, along the Elkhorn, Platte, Missouri, and Big Nemaha River valleys where ground water is very close to the surface. Similarly high recharge values were obtained for the Sand Hills sections of the North and Middle Loup, as well as Cedar River and Beaver Creek valleys due to high infiltration rates of the sandy soil in the area. The westernmost and southwesternmost parts of the state were estimated to typically receive < 30 mm of recharge a year. 相似文献
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Application of a novel phytotoxicity assay for the detection of herbicides in Hervey Bay and the Great Sandy Straits 总被引：1，自引：0，他引：1
A novel phytotoxicity assay was incorporated into an environmental assessment of Hervey Bay and the Great Sandy Straits, to investigate the role of run-off associated herbicides in the deteriorated health of intertidal seagrass meadows. Dose response curves of common herbicides were performed and their toxicity equivalents elucidated to assist in analysis. The results of the assay were reproducible and corresponded strongly with results of chemical analyses. The incorporation of the assay into the assessment of surface waters added an important aspect to the study by allowing investigation of the toxicity of cumulative herbicide concentrations and yielding biologically relevant data. The highest herbicide concentration detected during the study was equivalent to 0.23 microg l(-1) diuron; a concentration known to inhibit photosynthetic efficiency of the assay biomaterial by approximately 3%. 相似文献
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