织金洞CO_2浓度空间分布与昼夜变化的规律及成因分析  

Study on Spatial Distribution and Diurnal Variation and Causes of Carbon Dioxide Concentration in Zhijin Cave Environment

作　　者：张强[1] 周忠发[1] 陈全[1] 谢雅婷[1] 

机构地区：[1]贵州师范大学喀斯特研究院国家喀斯特石漠化防治工程技术研究中心,贵阳550001

出　　处：《科学技术与工程》2016年第26期18-27,共10页Science Technology and Engineering

基　　金：国家自然科学基金项目(41361081);贵州省科技计划(黔科合G字[2014]4004-2号);贵州省重大应用基础研究项目(黔科合JZ字[2014]200201)资助

摘　　要：为获取织金洞CO2浓度的连续昼夜变化情况,分别以4 h为间隔,对洞内41个点和以15 min间隔对洞内4个监测点,进行连续昼夜监测分析。研究表明：1织金洞中稳定段CO2浓度变化与海拔的相关性较高,集中在距入口相对高差20 m范围内变动,洞口段CO2空间变化差异主要与洞道结构和裂隙发育情况有关,其水平对流强度大于其垂直下沉;2观测期间洞内CO2浓度呈类正弦曲线的准周期昼夜变化,分别以19：0020：00和03：0004：0008：00为峰值和谷值;3织金洞CO2浓度变化受旅游活动、洞穴内外空气对流交换扩散及滴水脱气过程的多重影响,30年对外旅游开放使洞内温度升高23.5℃,CO2浓度升高约50 mg/L,初步说明整体上自然因素强于游客活动的影响;旅游旺季游客活动明显增强。深入研究其不同尺度时空变化,有助于揭示洞穴微气候变化及其与大气间交换响应的耦合过程及洞穴系统的碳循环特征与源汇关系,进而分析次生沉积物的沉积与再溶蚀机制,为开发和保护织金洞提供依据。To explore the diurnal continually variation of cave air CO2 in a short-time,a systematic monitoring with an interval of four hours and sampling in Zhijin Cave was took on,and analysis shows that： 1 Cave CO2 concentration up-and-down in the stilling chamber during the range from the entrance-standard relative relief 20 m,which is mainly related to the monitoring sites elevation,with a high correlation coefficient of 0. 908,and in the opening multi-hole and closing single import section it displays opposite fluctuation rule,which may be related to the development of the tunnel structure and fracture,and horizontal convection intensity is stronger than vertical drop strength; 2During the observation,CO2 concentration shows an obvious class sine curve of diurnal periodicity,with a peak-to-valley in 19： 00 20： 00 and 03： 00 04： 00 08： 00,respectively; 3The resource of CO2 in Zhijin cave is mainly from tourism activities and then from the process of air horizontal convection exchange and diffuse in the exterior and interior,and degassing from fissure drip-water,within the 30-year opening from 1985,cave temperature was increased about 2 3. 5 ℃ while the CO2 concentration was about 50 mg / L,which physical factors preliminarily show a larger function than the tourism,on the whole,while tourist absolutely increased in peak season. The comprehensive research of different time-scale of spatial-temporal change of CO2 on interpretation of cave microclimate change and exchange-response with atmosphere,,carbon cycling,sink and source becomes increasingly important in karst aquifer systems. and then analysis of the mechanisms of deposition and redissolution of secondary sediment can provide a basis for development and protection of Zhijin Cave.

关 键 词：洞穴环境 CO2浓度 空间分布 昼夜变化 织金洞 

分 类 号：P642.25[天文地球—工程地质学]