摘要
通过对雪玉洞上方山神庙和火石垭两处土壤CO2和出露于上覆基岩中的红庙水井和一碗水两处表层岩溶泉水化学特征近1年的监测,发现各深度(20,30,60cm)土壤CO2浓度在300～30 000ml/m3范围内变化,呈现夏秋高、冬春低的特点。其中火石垭土壤CO2浓度在2011年10月3个不同深度土壤层都出现明显低值,指示了外界干湿条件的变化。随深度的增加,土壤CO2浓度表现出递增的趋势,但是受不同因素的影响不同地点、不同土壤层中CO2浓度的变化有所不同。表层岩溶泉水化学对土壤CO2浓度的变化具有较好的响应,Ca2+、HCO3-、电导率(EC)与土壤CO2浓度的变化趋势基本一致,呈现夏秋高、冬春低的特点。pH值与土壤CO2浓度的变化趋势相反,呈现夏秋低、冬春高的特点。全年表层岩溶泉水的方解石饱和指数(SIc)>0,Ca2+处于饱和状态,但季节变化明显。二氧化碳分压(P(CO2))与方解石饱和指数变化趋势相反,二者在2011年10月都出现极值,反映出表层岩溶泉水化学的变化受土壤CO2影响显著。
Based on the monitoring of the soil CO2 and the hydrochemistry of epikarst spring above Xueyu cave in 2011, following results were observed： The concentration of soil CO2 in each layer（20, 30, 60 cm） varied between 300 ml/ma and 30 000 ml/ma , it was high in summer and fall, low in spring and winter. Specially, the concentration of soil CO2 showed low level in October, 2011, from the depth of 20 cm to 60 cm, indicating the changing of the environment around the Xuyu cave. The concentration of soil COa increased as the monitoring layer being lower, but affected by many factors, the concentration of soil COz varied differently. For example, in one monitoring site（Shanshen）, it was high in the layer of 30 cm and low in 60 cm in May, 2011. The hydrochemistry of the epikarst spring responded to the concentration of soil CO2 well, the variations of Ca2＋ , HCO;- and EC in epikarst spring remain consistent with the variations of soil CO2 concentration, and it was high in summer and autumn, low in winter and spring. But the variations of pH and Mg2＋ were reversed to the variations of soil CO2 concentration. The calcite saturation index（Sic） was always above zero in 2011, but changed differently each month. Compared to Sic, the variation of carbon dioxide partial pressure（P（CO2）） was reversed. All the parameters presented that the hydrochemistry of the epikarst spring was affected by the changing of soil CO2.
出处
《水土保持学报》
CSCD
北大核心
2013年第2期85-89,共5页
Journal of Soil and Water Conservation
基金
国家自然科学基金项目(41072192,41103068)
重庆市科委院士专项(CSTC.2010BC7004)
重庆市国土房管局科技项目
关键词
土壤CO2
表层岩溶泉
水化学
重庆雪玉洞
soil CO2
epikarst spring
hydrochemistry characteristics
Xueyu cave in Chongqing
