旅游洞穴空气环境时空变化特征及其影响因素——以贵州省绥阳大风洞为例

Characteristics of spatial temporal variation of air environment in tourism cave and its cause analysis:A case study of the Dafeng cave in Suiyang county,Guizhou Province

为探究绥阳大风洞空气环境时空变化的规律及其成因,沿洞道布设10个监测点,并对各点在垂直剖面上(洞道上、中、下部)的温度、湿度和CO_2浓度进行为期11个月的监测,结果表明:(1)大风洞空气环境要素(CO_2、温度、相对湿度)均呈现出明显的季节变化,大体上CO_2、温度和湿度表现为冬季低,夏季高的特点。(2)春、夏、秋季洞内外空气交换较弱,由洞口至洞内深处CO_2浓度、湿度逐渐增加,温度逐渐减小,且越往洞内深处,空气交换减弱,各参数变化越稳定;冬季洞内外空气交换作用强,由洞口至洞穴深部,温度变化曲线表现为并无突变点,且洞穴CO_2、湿度的垂直变化加大。(3)垂直变化上,春、夏、秋季洞穴CO_2浓度、相对湿度差异大,洞底部CO_2浓度和相对湿度大多高于洞顶部,但越往洞穴深入,3个环境参数的垂直差异均减小。

This study is to explore the fact and causes of the spatial and temporal variation of air environment in the Dafeng cave. 10 monitoring points were set up along the horizontal tunnel of Dafeng cave; and CO2 concentration,temperature and relative humidity of each monitoring point had been continuously monitored for a period of 11 months （from October 2015 to August 2016）. Through the analysis of these data gained from the cave, its air environment variation can be summarized as follows, （1）The air environment elements （i. e. CO2, temperature, relative humidity） of the tunnel show an obvious seasonal variation. In general, their values are low in winter and high in summer; （2）Due to weak air exchange with the external in the sea- sons of spring, summer and autumn, the CO2 concentration and humidity gradually increase to the deep in the cave, while the temperature gradually decreases, and all of which stabilize at a certain depth of the cave tunnel owing to very limited cave air exchange with the outside. In winter time, the temperature curve does not indicate the abrupt change, but the CO2 content and humidity fluctuate much in vertical direction from the roof to the bottom; （3）Vertically （from the bottom to the cave roof）, the values of CO2 concentration and humidity are different and they are higher at the bottom than those of the cave roof. To the further deep cave these three environmental elements get stabilized.