岩溶洞穴生态环境容量及影响因素分析:以绥阳大风洞-响水洞为例

Analysis of Ecological Environment Capacity and Influencing Factors of Karst Cave:Taking Dafeng-Xiangshui Caves,Suiyang as an Example

洞穴生态环境较为脆弱,环境承载力有限。为探究洞穴生态环境容量,文章以贵州绥阳双河洞系支洞——大风洞和响水洞为研究对象,通过对洞穴空气环境的长期监测分析,基于洞穴空气环境的时空变化特征和洞穴生态环境容量的测算方法,以CO_(2)作为测算指标,定量分析洞穴生态环境容量。结果表明:(1)长时间尺度下洞穴CO_(2)浓度、温度和相对湿度均呈现夏季高、冬季低的季节性变化特征。其中CO_(2)浓度的季节性显著,波动范围在(432~1319)×10^(-6)(体积浓度),夏季平均值达1148×10^(-6),冬季为528×10^(-6),年平均值为849×10^(-6)。(2)短时间高强度旅游活动对洞穴CO_(2)浓度影响较大,各监测点CO_(2)浓度与游客总量呈正相关性,2018年游客数量的减少导致洞内各监测点CO_(2)浓度普遍低于2017年,监测点神泉玉露和夜明珠的温度日增幅分别在0.03~0.15℃和0.07~0.33℃之间,相对湿度基本保持在99%以上。(3)洞穴生态环境容量在8月降至一年中的最小值,约11253人次/d,在1-3月及12月这4个月较大且稳定,平均值达15839人次/d,其季节性变化具体表现为冬季(15814人次/d)>春季(14792人次/d)>秋季(13719人次/d)>夏季(11806人次/d);旅游高峰期,洞穴生态环境容量随洞内CO_(2)背景值的变化而不同。(4)洞穴生态环境容量主要受洞穴规模形态、通风效应、自净能力等因素影响,洞道狭窄复杂、通风效应弱、CO_(2)浓度高、自净能力差的洞段将制约洞穴旅游容量,为避免旅游洞穴资源的闲置与浪费,在旅游高峰期需要分批分时段控制游客量,或在保障洞内生态系统稳定基础上对洞穴空气进行必要的人为调节,最终实现洞穴保护与洞穴旅游协调可持续发展。

The cave ecosystem is fragile and carrying capacity is limited.In order to explore the ecological environment capacity of caves,Dafeng and Xiangshui Caves as the branch caves of Shuanghe cave system in Suiyang,Guizhou Province,are taken as the research objects.Through the long-term monitoring and analysis of the cave air environment,based on the spatiotemporal variation characteristics of the cave air environment and the calculation method of the cave ecological environment capacity,CO_(2) is taken as the calculation index to quantitatively analyze the cave ecological environment capacity.The results show that CO_(2) concentration,temperature and relative humidity of the caves all present the seasonal variation characteristics of high summer and low winter.The CO_(2) concentration is seasonally significant,with fluctuations ranging from 432 to 1319×10^(-6),with an average of 1148×10^(-6) in summer,528×10^(-6) in winter,and an annual average of 849×10^(-6).Short-term high-intensity tourism activities have a greater impact on the CO_(2) concentration of the cave.The CO_(2) concentration at each monitoring point is positively correlated with the total number of tourists.The decrease in the number of tourists in 2018 caused the CO_(2) concentration at each monitoring point in the cave to be generally lower than 2017.The daily temperature increase at the monitoring points Shenquan Yulu and Yemingzhu is between 0.03~0.15℃ and 0.07~0.33℃ respectively,and the relative humidity is basically maintained above 99%.The ecological environment capacity of the cave fell to the minimum value of the year in August,about 11253 person-times/day.It was relatively large and stable during the four months from January to March and December,with an average of 15839 person-times/day.The specific seasonal changes are winter(15814 person-times/day)>spring(14792 person-times/day)>autumn(13719 person-times/day)>summer(11806 persontimes/day).During the peak period of tourism,the ecological environment capacity of the cave varies with the change of the background value of CO_(2) in the cave.Influenced by the size and shape of the cave,ventilation effect,self purification capacity and other factors,the narrow and complex tunnel section with high CO_(2) concentration will restrict the capacity of cave tourism.In order to avoid the idleness and waste of tourism cave resources,it is necessary to control the number of tourists in batches and time periods during the peak period of tourism,or adjust the cave air on the basis of ensuring the stability of the ecological system in the cave,so as to realize the coordinated and sustainable development of cave protection and cave tourism.