中国西部干旱区生态景观制图的若干问题

生态景观制图是专题制图学的重要方向.通过制图可以反映自然要素和人为作用的特点,揭示生态景观要素的耦合关系.生态景观制图中专题要素的表现方式,制图过程的数据采集,制图单元的划分,制图的模式选择,以及遥感、GIS与数字制图手段的应用,是干旱区景观生态制图的关键问题.生态景观制图中的地图信息理论、地图模式论、地图分析理论、地图要素综合理论、制图工艺学等的发展,对于开拓资源环境制图学的新领域具有理论价值,并对生态规划与生态建设具有重要促进作用

陕北风沙区景观格局分析

陕北风沙区地处农牧交错带 ,气候干旱 ,是一个从沙区向黄土区的过渡区 ,自然环境复杂、恶劣。区内景观类型简单 ,半流动沙地、流动沙地占据了主体 ,是一种典型的沙地景观格局。水是区域景观发展的一个重要因素 ,绿色景观滩地、草地、林地仅有 14 .7% ,显示出区内生产力低 ,生态环境脆弱。人为景观成为区域内仅次于沙地的景观大类 ,区内自然的景观格局正受到人类的强烈干扰。这种区域环境的过渡性及脆弱性 ,导致了区域景观结构的不稳定性与敏感性

中国西部干旱区生态景观制图的若干问题

制图方法是认识和揭示客观现象与过程的重要途径。生态景观制图作为专题制图学的一个重要方向，通过建立分类体系，制定分类方法，编制专题图件，可以反映自然要素和人为作用的特点，揭示生态景观要素的耦合关系。生态景观制图中专题要素的表现方式，制图过程的数据采集，制图单元的划分，制图的模式选择，以及遥感、GIS与数字制图手段的应用，是干旱区景观生态制图的关键问题。生态景观制图中的地图信息理论、地图模式论、地图分析理论、地图要素综合理论、制图工艺学等的发展，对于开拓资源环境制图学的新领域具有理论价值，并对生态规划与生态建设具有重要促进作用

干旱区内陆河流域生态系统脆弱性与生态安全研究

该项目探索了生态系统脆弱性特征及评价原理，首次应用数量化理论、模糊数学理论、模型分析方法等建立了以塔里木河流域为代表的干旱区内陆河流域生态系统脆弱性评价指标体系及评价标准，揭示了塔里木河流域生态环境质量定性及定量等级。首次建立了干旱区内陆河流域生态系统脆弱性评价的模式与方法，构建了生态脆弱性指数与定量评价的综合标准。将遥感地学分析方法及GIS技术相结合，提取生态格局变化信息。同时，把现代地图学的理论与方法，应用到了脆弱生态环境的领域。首次提出生态系统耦合的概念、原理与方法，并在MODS格局下，将生态系统脆弱性评价与生态安全相联系

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies