中国代表性滑雪场网络关注度时空演变及影响因素

基于百度指数数据,运用指数测度、空间地理分析、回归模型和地理探测器,对2011—2019年中国大陆26个代表性滑雪场网络关注度的时空演变特征及影响因素进行分析。结果表明:(1)时间演化上,网络关注度呈先增后减且逐渐平稳的规律。2015年、2016年为峰值年份,季节性差异明显,共两个波动峰值且为“南北为单,中东为双”的分布格局。(2)空间特性上,全国和地区均为先增后减特征,地区差异显著;变异程度先降后增并趋于稳定,全国分布相对稳定平衡,地区分布呈不稳定集聚特性。省区冷热区域分布总体呈“东北热—西南冷”格局,层级变化以稳定型为主。(3)滑雪场层面上,滑雪场总体偏好层级变动较大,高偏好保持稳定领先,其余层级以下降变动为主。滑雪场冷热点分级呈“北热南冷”的格局,东北、华北两个热点集聚区域演变较为稳定。(4)影响因素上,需求侧影响因素排序为滑雪消费吸引力>受教育程度>经济发展水平>信息化水平>滑雪场建设水平。供给侧的滑雪人次占比、滑雪经济贡献、客运承载力、冰雪旅游资源丰度、官方媒体建设水平解释力较强,其他因素影响并不显著。     

基于AWRSEI的岱海流域生态环境质量时空演变及驱动因子分析

流域是重要的生态安全屏障和社会经济发展区域,为了更加客观准确地评价干旱和半干旱区流域生态环境质量,基于遥感生态指数（RSEI）引入盐度指标构建适用于干旱和半干旱区流域的遥感生态指数（AWRSEI）并以岱海流域为例分析其适用性.基于AWRSEI模型,采用4期Landsat TM/OLI合成影像,对2001~2020年岱海流域的生态环境质量进行定量评价,通过变异系数和空间自相关分析岱海流域生态环境质量时空演变规律,并通过地理探测器进行成因分析和驱动因子解释力分析.结果表明：①AWRSEI与各生态因子的平均相关系数为0.860,比单个指标分量更具代表性;第一主成分的荷载正负值和排序与RSEI一致,特征值贡献率比RSEI高3.69%,评价结果与真实地表情况更为接近,适合用于干旱区流域的生态环境质量评价.②岱海流域2001~2020年AWRSEI指数的年均值为0.427,生态环境质量基础较差,期间AWRSEI的均值呈现波动上升的趋势,并且在2020年均值达到最高0.502.整体生态环境质量明显好转,恶化区域减少了20.51%,改善区域增加了12.71%.空间分布上,岱海流域南部和西北部高海拔地区的林地生态环境质量优,北部和南部中海拔地区生态环境质量较差,湖区北侧生态环境质量优于南侧.③岱海流域AWRSEI变异系数平均值为0.280,生态环境质量状况稳定,整体变化波动较小,高波动主要集中在湖区南侧和居民点区域.岱海流域生态环境质量存在显著的空间自相关性,高-高集聚区主要分布在高海拔的林地区域和低海拔耕地区域;低-低集聚区零星分布在中海拔区域.④2001~2020年岱海流域生态环境的提升主要由于NDVI提高,NDBSI和NDSI降低.NDVI和NDBSI是交互作用最强的组合,对生态环境的解释力最强.土地利用是AWRSEI的主导因子,解释力最强.土地利用和气象因子的组合是交互作用最强,且各驱动因子之间均为增强关系.     

贵州高原典型喀斯特县域生境质量时空演变及定量归因

揭示贵州高原喀斯特县域生境质量时空演变规律及其驱动因素,为平衡喀斯特区域生态保护和可持续发展提供科学依据.利用1989年、2003年、2010年和2020年4期土地利用数据、DEM数据、气象数据和社会经济数据,采用InVEST模型阐明普定县近30年生境质量时空分布格局及演变特征,并对其空间分异的驱动力进行了定量探测.结果表明：①耕地和林地是普定县的主要土地利用类型,构成了地表覆盖景观基质.2003~2010年土地利用变化最显著,其中林地的增幅最大,达86.42%,耕地是流失最严重的土地利用类型,面积减少157.57 km²,主要流向林地和建设用地;②1989~2020年普定县生境质量指数平均值由0.60上升至0.73,空间上由东北部向西南部大体呈现出“高-低-高”的分布格局,生境质量高值区主要分布在东北部林地和草地区,低值区集中在中部和南部的建设用地,生境质量等级上升的区域主要集中在东部及西北部的大部分地区;③土地利用类型是影响生境质量时空分布的首要因素,解释程度为91.00%.在交互作用探测中,任意两种影响因素的交互作用大于单个因素的单独作用,土地利用类型和年均降水量的交互作用最强,达到96.00%,其与岩性因子的交互作用达到94.00%,自然与人文因素共同主导生境质量的时空变化.1989~2020年普定县生境质量总体较好,土地利用类型变化与生境质量关系密切,优化土地利用结构、减小人类活动的影响对提高普定县生境质量具有重要意义.     

可燃气体报警器快速校准装置的研究

针对石化企业中可燃气体报警器校准工作存在着校准周期长、维护困难、准确性不能保证的现状,提出了一种通过将高浓度可燃气体物质经过定量稀释配制成用于可燃气体报警器标定的多种浓度气体物质的方法,并设计了一种由两路流量检测与控制模块和一个监控单元构成的可燃气体报警器快速标定装置。叙述了可燃气体报警器快速标定装置的原理、元器件构成、设计结构、流量控制方法和防爆措施的实现。     

INCREASING WATER SUPPLY BY MIXING OF FRESH AND SALINE GROUND WATERS1

ABSTRACT: The quality of ground water in any aquifer takes its final form due to natural mixture of waters, which may originate from different sources. Water quality varies from one aquifer to another and even within the same aquifer itself. Different ground water quality is obtained from wells and is mixed in a common reservoir prior to any consumption. This artificial mixing enables an increase in available ground water of a desired quality for agricultural or residential purposes. The question remains as to what proportions of water from different wells should be mixed together to achieve a desired water quality for this artificial mixture. Two sets of laboratory experiments were carried out, namely, the addition of saline water to a fixed volume of fresh water. After each addition, the mixture volume and the electric conductivity value of the artificially mixed water were recorded. The experiments were carried out under the same laboratory temperature of 20°C. A standard curve was developed first experimentally and then confirmed theoretically. This curve is useful in determining either the volume or discharge ratio from two wells to achieve a predetermined electrical conductivity value of the artificial mixture. The application of the curve is given for two wells within the Quaternary deposits in the western part of the Kingdom of Saudi Arabia.     

Ozone Deposition at a Forest Site in NE Bavaria

The dry deposition of ozone to aconiferous forest in northeastern Bavaria(southern Germany) was quantified during 1999with both the eddy correlation method and a bigleaf model. The model included parameterizationsof the atmospheric transfer resistances fromdirect measurements, stomatal resistance from aplant ecological model, and an estimation of thecuticle resistance as function of leaf wetness.Early in the season, the measured and themodelled deposition fluxes were in goodagreement, although the modelled fluxes tended tounderestimate the measured ones. Thisunderestimation was more pronounced in the latesummer, when high nocturnal fluxes werefrequently measured. The model parameterizationof the cuticle and the stomatal resistances didnot allow for such high fluxes. In these cases,the 24 hour average of the measured fluxes wereup to 4.5 times higher than the modelled ones.The reasons for these large discrepancies remainunknown. However, assigning the unaccounted partof the deposition to a nonstomatal surfacedeposition pathway, a new parameterization of therespective resistance yielded an average value of300 s m^-1. It exhibited a decreasing trendthrough the vegetation period.     

Municipal sludge as landfill barrier material

The aim of this research is to find substitute barrier materials for natural clay from two kinds of municipal sludge: waterworks sludge( Sw ) and dredging sludge( Sd ). Laboratory tests were performed firstly to determine their Atterberg limits and hydraulic conductivity.Based on the results, the use of waterworks sludge was recommended. Then, shear strength tests were performed and it was found the shear resistance property of waterworks sludge is strong enough to maintain slope stability. In order to evaluate the possibility of secondary pollution, the heavy metal contents of waterworks sludge was determined and the results indicated that secondary pollution is unlikely happened. Finally, economic analysis proves that reusing waterworks sludge as barrier will reduce the lost a great for both landfill and waterworks. Based on the results, waterworks sludge was proposed to use and a further long-term simulated landfill test was suggested.     

城市生活垃圾渗透系数测试研究

采用常水头测渗实验,对不同压实密度和水力梯度下的新鲜垃圾与陈垃圾的渗透系数进行测试,根据达西定律求得渗透系数值。由于垃圾的不均匀性、小颗粒的运动和大孔隙沟道流的形成和改变,实验初始阶段渗透系数值先增大至峰值,然后缓慢降低直至趋于稳定。实验稳定后,新鲜垃圾压实密度为0.75~0.95 t/m3时,渗透系数值约为1.26E-03~1.43E-03 cm/s。陈垃圾在压实密度分别为1.2和1.4 t/m3时,渗透系数为8.29E-04和1.35E-04 cm/s。     

基于地理探测器的土壤重金属空间分异及其影响因素分析研究进展

地理探测器是探测空间分异性,以及揭示其背后驱动因子的一种新的统计学方法,由于其既能揭示单一因素对因变量的影响,也能评价双因素相互作用的影响,且不需要考虑线性,还能避免多变量共线性的影响,没有较强的模型假设,解决了传统方法在分析类别变量时的局限性,在土壤重金属空间分异领域研究的应用越来越广泛.通过收集40篇关于地理探测器在土壤重金属空间分异领域的研究报道,梳理了采用的自变量离散化方法、研究尺度、因变量和自变量类型、因子探测、交换探测、风险探测和生态探测等内容,并提出下一步的应用研究急需明确的问题,为地理探测器在土壤重金属空间分异领域深层次应用提供支撑.     

便携式重金属测定仪在龙江河镉离子污染事件应急监测中的应用研究

PDV6000plus便携式重金属测定仪具有体积小、精度高、操作简便等特点,能够快速完成样品分析,为环境管理部门在突发环境污染事件中及时掌握污染变化趋势,作出科学决策提供技术支持。本文通过介绍便携式重金属测定仪在广西龙江河镉离子污染事件应急监测中的具体应用,以期为今后在应急监测中更好地发挥作用提供参考。