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11.
本文对张道口-1井模拟水位、数字化水位观测精度进行了对比,进一步分析了影响数字化水位观测精度的几个因素,提出了数字化水位在日常观测中应注意的几个问题。 相似文献
12.
为评估污染减排措施实施效果,基于地基观测及排放清单数据,运用WRF中尺度气象模型和CAMx空气质量模型,对德州市2017-2019年秋冬季大气污染攻坚实施效果进行了评估.结果表明,2017-2018年秋冬季,德州市ρ(PM2.5)同比下降31.7%,高于京津冀及周边地区平均水平(25.6%),大气污染攻坚措施成效显著;2018-2019年秋冬季,德州市ρ(PM2.5)同比增加8.5%,高于京津冀及周边地区平均水平(4.2%),这与不利气象条件及排放量同比减少有关.观测结果显示,2018-2019秋冬季,德州市PM2.5中无机组分、一次排放示踪物以及SO2和CO等气态前体物浓度较上一年度呈下降趋势,ρ(SOA)(SOA为二次有机气溶胶)、ρ(NH4+)同比有大幅增长,增幅分别为53.8%和19.1%,这与大气中VOCs(挥发性有机物,增加46.5%)及大气氧化性(增加6.4%)的增加密切相关,表明德州市复合型大气污染加剧,PM2.5防控难度加大.综合气象和减排评估结果可知,2017-2018年秋冬季,气象条件(13.4%)和长效措施(9.4%)是德州市PM2.5改善的两个主要因素;2018-2019年秋冬季,长效措施减排效果较为有限,减排主要来自预警应急(5.0%)和区域减排(5.2%),若仅考虑不利气象条件的影响,将导致同比约19.9%的反弹.因此,持续深入推进长效减排措施,降低污染物排放水平,是德州市实现空气质量改善的根本途径. 相似文献
13.
Matthew A. Williamson Brett G. Dickson Mevin B. Hooten Rose A. Graves Mark N. Lubell Mark W. Schwartz 《Conservation biology》2021,35(4):1174-1185
Private lands provide key habitat for imperiled species and are core components of function protectected area networks; yet, their incorporation into national and regional conservation planning has been challenging. Identifying locations where private landowners are likely to participate in conservation initiatives can help avoid conflict and clarify trade-offs between ecological benefits and sociopolitical costs. Empirical, spatially explicit assessment of the factors associated with conservation on private land is an emerging tool for identifying future conservation opportunities. However, most data on private land conservation are voluntarily reported and incomplete, which complicates these assessments. We used a novel application of occupancy models to analyze the occurrence of conservation easements on private land. We compared multiple formulations of occupancy models with a logistic regression model to predict the locations of conservation easements based on a spatially explicit social–ecological systems framework. We combined a simulation experiment with a case study of easement data in Idaho and Montana (United States) to illustrate the utility of the occupancy framework for modeling conservation on private land. Occupancy models that explicitly accounted for variation in reporting produced estimates of predictors that were substantially less biased than estimates produced by logistic regression under all simulated conditions. Occupancy models produced estimates for the 6 predictors we evaluated in our case study that were larger in magnitude, but less certain than those produced by logistic regression. These results suggest that occupancy models result in qualitatively different inferences regarding the effects of predictors on conservation easement occurrence than logistic regression and highlight the importance of integrating variable and incomplete reporting of participation in empirical analysis of conservation initiatives. Failure to do so can lead to emphasizing the wrong social, institutional, and environmental factors that enable conservation and underestimating conservation opportunities in landscapes where social norms or institutional constraints inhibit reporting. 相似文献
14.
The need for robust evidence to support conservation actions has driven the adoption of systematic approaches to research synthesis in ecology. However, applying systematic review to complex or open questions remains challenging, and this task is becoming more difficult as the quantity of scientific literature increases. We drew on the science of linguistics for guidance as to why the process of identifying and sorting information during systematic review remains so labor intensive, and to provide potential solutions. Several linguistic properties of peer‐reviewed corpora—including nonrandom selection of review topics, small‐world properties of semantic networks, and spatiotemporal variation in word meaning—greatly increase the effort needed to complete the systematic review process. Conversely, the resolution of these semantic complexities is a common motivation for narrative reviews, but this process is rarely enacted with the rigor applied during linguistic analysis. Therefore, linguistics provides a unifying framework for understanding some key challenges of systematic review and highlights 2 useful directions for future research. First, in cases where semantic complexity generates barriers to synthesis, ecologists should consider drawing on existing methods—such as natural language processing or the construction of research thesauri and ontologies—that provide tools for mapping and resolving that complexity. These tools could help individual researchers classify research material in a more robust manner and provide valuable guidance for future researchers on that topic. Second, a linguistic perspective highlights that scientific writing is a rich resource worthy of detailed study, an observation that can sometimes be lost during the search for data during systematic review or meta‐analysis. For example, mapping semantic networks can reveal redundancy and complementarity among scientific concepts, leading to new insights and research questions. Consequently, wider adoption of linguistic approaches may facilitate improved rigor and richness in research synthesis. 相似文献
15.
汶川地震在江苏的强震动记录及地震影响场 总被引:1,自引:0,他引:1
2008年5月12日四川汶川发生M8.0大地震,江苏数字强震动台网固定观测台站、宿迁和溧阳断层观测存放台阵共获取该次地震有效强震动事件45个,计134条加速度记录。本文介绍了这些强震动记录分析处理的基本情况及其时域与频域的一些特点;编写SICalculate谱烈度计算程序和D2InterP二维插值程序,输入所获取的汶川地震26组实测强震动记录数据,得到该次地震在江苏地区的峰值加速度与谱烈度的等值线图,并就区域内地震影响场特征进行了初步研究。 相似文献
16.
Despite several decades of research on the effects of fragmentation and habitat change on biodiversity, there remain strong biases in the geographical regions and taxonomic species studied. The knowledge gaps resulting from these biases are of particular concern if the forests most threatened with modification are also those for which the effects of such change are most poorly understood. To quantify the nature and magnitude of such biases, we conducted a systematic review of the published literature on forest fragmentation in the tropics for the period 1980–2012. Studies included focused on any type of response of single species, communities, or assemblages of any taxonomic group to tropical forest fragmentation and on fragmentation‐related changes to forests. Of the 853 studies we found in the SCOPUS database, 64% were conducted in the Neotropics, 13% in Asia, 10% in the Afrotropics, and 5% in Australasia. Thus, although the Afrotropics is subject to the highest rates of deforestation globally, it was the most disproportionately poorly studied biome. Significant taxonomic biases were identified. Of the taxonomic groups considered, herpetofauna was the least studied in the tropics, particularly in Africa. Research examining patterns of species distribution was by far the most common type (72%), and work focused on ecological processes (28%) was rare in all biomes, but particularly in the Afrotropics and for fauna. We suggest research efforts be directed toward less‐studied biogeographic regions, particularly where the threat of forest fragmentation continues to be high. Increased research investment in the Afrotropics will be important to build knowledge of threats and inform responses in a region where almost no efforts to restore its fragmented landscapes have yet begun and forest protection is arguably most tenuous. Sesgos Biogeográficos y Taxonómicos en la Investigación de la Fragmentación de Bosques Tropicales 相似文献
17.
通过分析厦门地震台数字化观测中出现的误处理事件,查找出诸多原因,如预处理软件存在BUG、数据处理方法不当、电源故障等。也提出一些预防办法。 相似文献
18.
若尔盖高原湿地藻类多样性研究 总被引:1,自引:1,他引:0
分别于夏、冬两季采集若尔盖高原湿地水样,利用传统培养及显微镜检的方法和现代分子生物学方法对其藻类多样性进行了研究.结果表明,夏季水样至少培养出4种绿藻,分别为普通小球藻(Chlorella vulgaris Beij.)、浮球藻(Planktosphaeriagelatinosa G.M.Smith)、繁茂栅列藻(Scenedesmus abundans Kirchner)和柱状栅列藻(Scenedesmus bijuga Turp.),均属于绿球藻(Chlorococcales),其中普通小球藻为优势藻种,并被分离纯化.显微镜检结果表明冬季水样中主要的藻类种群为硅藻,此结果符合在低温季节天然水体中常以硅藻为主的常理.蓝藻16S rRNA基因克隆文库中的主要类群为硅藻(Bacillaripiophyta,35.3%),其次为蓝藻,包括色球藻(Chroococcales,5.9%)、念珠藻(Nostocales,11.8%)、颤藻(Oscillatoriales,11.8%)和一些未知种属的蓝藻类群(Unclassified Cyanobacteria,35.3%),还发现一些与低温环境微生物相关的类群,如颤藻目细纤菌属(Leptolyngbya). 相似文献
19.
空气自动监测系统的正常运行需要有严格的质量保证和管理方法,青岛市空气自动监测系统已正常运行了二十多年。运行期间,通过查阅大量的国内外资料并结合实际工作需要逐步建立了一套适合目前监测状况的质量保证和控制方法,并取得了较好的效果。 相似文献
20.
回顾了地震观测技术发展的三个阶段及其特点。简要总结了随着这几个阶段的技术进步南京基准地震台观测技术的重要变革 ,并从记录地震事件数量、大地震速报作用和推动某些研究的深入等方面评估了由于这些技术进步所带来的地震台效能的提高。对目前地震观测技术从模拟观测向数字观测的转折时期 ,地震台如何尽快过渡 ,充分发挥效能提出了初步对策。 相似文献