基于IPA法的传统型景区游客满意度评价——以琅琊山景区为例

游客满意度评价对景区规划、建设和管理很重要。结合文献分析与德尔菲法,构建了传统型景区游客满意度评价指标体系,并以琅琊山景区为例采用IPA模型进行案例分析。结果表明:琅琊山景区7个要素测度层——资源特色、景区环境、景区产品、景区交通、景区服务、景区设施、景区价格及30项因子测度指标感知均值都为满意度重要性,游后感知实绩(满意度)全低于游前期望(重要性);IPA矩阵分析30项因子分布为:优势区域6项、修补区域4项、机会区域15项、维持区域5项,游后满意度(实绩)与游前重要性(期望)感知评价"双高项"占20.0%,"双低项"占50.0%。总体上游客期望值较高而满意度不高,各评价因子的满意度评价差异较大,景区需提升产品与服务。     

Evolution and spatial characteristics of tourism field strength of cities linked by high-speed rail (HSR) network in China

Traffic is an indispensable prerequisite for a tourism system. The “four vertical and four horizontal” HSR network represents an important milestone of the “traffic revolution” in China. It will affect the spatial pattern of tourism accessibility in Chinese cities, thus substantially increasing their power to attract tourists and their radiation force. This paper examines the evolution and spatial characteristics of the power to attract tourism of cities linked by China’s HSR network by measuring the influence of accessibility of 338 HSR-linked cities using GIS analysis. The results show the following. (1) The accessibility of Chinese cities is optimized by the HSR network, whose spatial pattern of accessibility exhibits an obvious traffic direction and causes a high-speed rail-corridor effect. (2) The spatial pattern of tourism field strength in Chinese cities exhibits the dual characteristics of multi-center annular divergence and dendritic diffusion. Dendritic diffusion is particularly more obvious along the HSR line. The change rate of urban tourism field strength forms a high-value corridor along the HSR line and exhibits a spatial pattern of decreasing area from the center to the outer limit along the HSR line. (3) The influence of the higher and highest tourism field strength areas along the HSR line is most significant, and the number of cities that distribute into these two types of tourism field strengths significantly increases: their area expands by more than 100%. HSR enhances the tourism field strength value of regional central cities, and the radiation range of tourism attraction extends along the HSR line.     

Adsorption characteristics of perchloroethylene in natural sandy materials with low organic carbon content

Laboratory batch tests were conducted to investigate the sorption isotherms and sorption kinetics of the chlorinated hydrocarbon perchloroethylene (PCE) in five natural sandy materials with an organic carbon content (f _oc) in the range 0.080–0.540%. The amended non-linear dual-mode model can describe the sorption isotherms in materials with f _oc in the range 0.080–0.090%. For a sample with a much higher f _oc of 0.54%, the absorption isotherm was found to fit a linear model. These results may indicate that organic carbon is not the main factor influencing the sorption isotherm. The sorption kinetics of PCE in samples with f _oc in the range 0.080–0.090% are not first-order and are different from those observed in the samples with higher f _oc. The sorption process in the materials with lower f _oc involves fast sorption, fast desorption and an equilibrium stage. The results may imply that the factors affecting sorption kinetics of PCE in low f _oc media are pore filling and capillary condensation rather than organic carbon content.     

塔中地区良里塔格组海平面变化对高频层序和沉积演化的控制

【研究目的】碳酸盐岩地层易受海平面变化影响而发育高频层序,但是反映海平面变化的地化指标的精度不足,导致高频层序对海平面振荡的响应认识不够深入,高频海平面变化对台地边缘礁滩沉积的高频层序和沉积演化的控制尚不明确。【研究方法】论文研究选取塔里木盆地塔中地区某钻井的上奥陶统良里塔格组连续取心资料,通过密集取样开展微相分析和碳、氧同位素测试分析。【研究结果】该井良里塔格组中上部发育7种微相类型,沉积演化分析表明良里塔格组沉积中—晚期,沉积环境由潮坪向生物礁-颗粒滩再到较深水的开阔台地演化。碳、氧同位素测试显示δ¹³C为0.5993‰~1.6228‰（均值1.139‰）,δ¹⁸O值为-8.3608‰~-5.1452‰（均值为-6.790‰）;δ¹³C和δ¹⁸O的振荡变化与微相变化和沉积旋回对应良好。古海洋条件分析表明,良里塔格组沉积时期气候温热,礁、滩体发育层段样品的古温度值最高,代表着高的碳酸盐产率;Z值所反映的古盐度在底部潮坪沉积段最高,在高频旋回的顶部古盐度均明显减小,指示可能存在大气淡水的影响。与塔北地区南缘和巴楚地区的δ¹³C和δ¹⁸O存在一定差异,主要受控于沉积环境和古水深。【结论】良里塔格组中—上部存在至少3个完整的海平面升降变化周期,内部又包括至少2个次级周期;不同级别的海平面振荡主要受古气候变化驱动,并控制了高频层序的发育。海平面先缓慢上升再持续稳定或小规模振荡,是连续厚层的生物碎屑和砂屑颗粒滩沉积发育的有利条件;良里塔格组沉积晚期海平面快速上升,沉积环境向滩间洼地和较深水的开阔台地转变。在高频层序顶部海平面的小规模下降导致的早期岩溶作用是礁滩体储层质量改善的重要因素。     

岩溶生态系统中的植物

岩溶生态系统是受岩溶环境制约的生态系统,是脆弱的生态系统,缺水、少土、富钙是岩溶生态系统无机环境的基本特征,植物与岩溶环境长期的相互作用,演化出独特的岩溶植物。岩溶植物具有喜钙性、石生性、旱生性,其多样性表现为少属科、寡种属和特有种,更有岩溶生态系统中特有的洞穴弱光带、天坑植物群落。植物是生态系统的生产者,肩负着生态系统的生产力、生态服务功能的重任,退化岩溶生态系统的修复,需要根据中国岩溶生态系统发育特色,探索发展具有仿自然特色的生态产业,走出岩溶区“绿水青山就是金山银山”的道路,完善中国岩溶生态系统理论。     

Discovery of scandium enrichment and its geological significance in the Dawanshan Neoproterozoic metamorphic basalts from the Mouding area in Central Yunnan Province,ChinaSCIEI北大核心CSCD

钪(Sc)是世界各国竞相争夺的关键金属矿产资源之一。滇中牟定大弯山变质玄武岩厚度>36.5m,出露面积0.5km^(2),形成时代为新元古代南华纪(781.3±1.9Ma)。本文对该变质玄武岩开展了全岩地球化学分析、全自动矿物分析(TESCAN TIMA)观测、NPPM薄片区域面扫和单矿物原位LA-ICPMS分析等研究,结果显示变质玄武岩全岩Sc含量为47.0×10^(-6)~97.9×10^(-6),平均含量为69.1×10^(-6),钪氧化物(Sc_(2)O_(3))平均含量为106×10^(-6),变质玄武岩空间Sc矿化特征稳定,具有形成钪矿资源的潜力。同时,变质玄武岩共伴生有钛和铁矿化,全岩TiO_(2)含量为2.57×10^(-2)~6.13×10^(-2),平均为4.25×10^(-2);TFe含量为13.3×10^(-2)~23.7×10^(-2),平均为17.7×10^(-2)。Sc可能存在类质同象和离子相两种赋存形式,类质同象形式Sc主要赋存于钛铁矿和金红石矿物中,钛铁矿中Sc含量为70.0×10^(-6)~168×10^(-6),平均值为108×10^(-6);金红石中Sc含量高达297×10^(-6);而磁铁矿、黑云母等矿物中Sc含量较低,均低于全岩Sc含量,对全岩Sc矿化贡献较小。牟定大弯山Sc矿化与以往报道侵入岩及其风化壳中Sc矿化在富集特征、赋存岩性和载体矿物等方面不同,是变质火山岩中新发现的Sc矿化信息,显示了较好的找矿潜力,对Sc资源勘查和研究具有重要指示意义。     

新型冠状病毒肺炎首次临床和CT特征价值分析

目的：分析2019新型冠状病毒肺炎（COVID-19）首次临床和CT特征价值。方法：回顾性分析90例临床确诊COVID-19患者的首诊症状、一般炎症指标和胸部CT,包括13例重型/危重型和77例轻型/普通型,并由两名经验丰富的影像诊断医师进行分析和比较。结果：相对于轻型/普通型COVID-19患者,重型/危重型最重要的临床特征为年龄较大,一般炎症指标上升,胸部CT显示肺部炎症指数（PII）更高。受试者工作特征曲线（ROC）显示C-反应蛋白（CRP）、PII区分重型/危重型和轻型/普通型COVID-19患者的灵敏度分别为69.2%、69.2%,特异度分别为83.1%、87.0%,曲面下面积（AUC）分别为0.775[95% CI （0.649,0.901）;P=0.002]、0.770[95% CI （0.621,0.920）;P=0.002],其联合的AUC为0.785[95% CI （0.644,0.927）;P=0.001]。结论：重型/危重型和轻型/普通型COVID-19患者的临床症状、炎症指标和胸部CT特征具有显著性区别,结合年龄、CRP和PII的检查,有助于早期识别重型/危重型COVID-19和评估其预后。     

渤海西岸暴雨中尺度对流系统的结构及成因

利用卫星、雷达和加密自动站等监测资料,结合VDRAS系统资料和1°×1° NCEP再分析资料,对造成黑昼和暴雨的中尺度对流系统的空间、热动力结构特征和发生、发展及维持原因进行了分析。结果表明:2004—2009年渤海西岸圆形α-中尺度对流系统有别于南方,其中只有16%可发展为中尺度复合体;黑昼现象是影响系统的特殊性所致。突发性暴雨的制造者是α-中尺度对流系统西端不断新生的β-中尺度对流系统,其发生、发展、维持与边界层内冷池外流、对流层低层 (1.3~2.4 km) 侵入的西北气流与西南气流形成的辐合线或交汇线有密切关系。α-中尺度对流系统的上升速度中心在500 hPa附近,多个β-中尺度对流系统分别具有独自的垂直气流和弱边界层环流。α-中尺度对流系统内部扰动温度呈下负上正的垂直分布,促使了不稳定层结趋于稳定;冷池呈东厚西薄的楔形结构,有利于β-中尺度对流系统发展维持。     

鹤壁市夏季一次雹暴过程的成因分析

运用天气图、物理量场、卫星云图、雷达回波及相关气象资料,分析了2005年6月19日发生在鹤壁的雷雨大风、并伴有局地冰雹的强对流天气过程.结果表明:在低层θse高能舌区内,地面冷锋移到 500 hPa高空急流出口区下方左侧时,高低空次级环流耦合,触发不稳定能量释放、产生强烈的上升运动,是这次强对流天气产生的直接原因.     

Seasonal and spatial variation in abundance and egg production of Paracalanus parvus (Copepoda: Calanoida) in/out Jiaozhou Bay, China

The spatial distribution of stage-specific abundance and reproduction of the copepod Paracalanus parvus were studied from October 2005 to September 2006 in the Jiaozhou Bay. This copepod occurred continuously in this bay throughout the year. The species reached the lowest abundance in April and peaked in June. From October to December, distribution center mainly occurred in offshore water and at the mouth of the bay. In winter, early copepodites and adults gradually decreased and till February, most of the population was only comprised of CIV–CV stages. Overwintering copepodites matured in March and males tended to mature before female. From May to September, each stage occurred in the population and gradually reached high abundance. Temperature and chlorophyll a (Chl-a) concentration in the three stations can't clearly explain the seasonal variation in stage-specific abundance, so we surmised the important effect of the Yellow Sea. Egg production rate (EPR) reached its lowest in winter and peaked in June at 60.8 eggs female⁻¹ day⁻¹ in nearshore water. In the warming period, EPR in nearshore water was statistically higher and EPR > 10 eggs female⁻¹ day⁻¹ lasted longer than that in offshore water, showing the importance of nearshore water for recruitment of P. parvus. Our study showed that EPR was positively related to temperature and total chlorophyll a in offshore water and mouth of the bay. In nearshore water, the relationships between EPR and temperature and Chl-a in three size fractions were not the same as those in offshore water, suggesting complicated ecosystem in such a eutrophic area in warming period.