CAJ | 학술논문

为探讨三峡水库运行初期小江回水区水体的光学特性,2007年5月～2008年5月对回水区5个断面水下光合有效辐射(PAR)与常规水质指标进行监测, 分析了真光层深度的时空特征及其影响因素.研究区域真光层深度空间差异不明显, 但季节变化显著, 冬季最高, 夏季最低.回归分析表明光合有效辐射(PAR)衰减系数与透明度、总悬浮物浓度有显著的相关性(R~2 =0.8619, R~2=0.764), 与叶绿素a相关性不明显(R~2=0.0113).进一步研究分析表明真光层深度、总悬浮物浓度、叶绿素a主要受小江河口流量、小江回水区水位的影响,复杂的水动力条件与独特的水文条件是影响三峡水库小江回水区真光层深度变化的主要因素.
위탐토삼협수고운행초기소강회수구수체적광학특성,2007년5월～2008년5월대회수구5개단면수하광합유효복사(PAR)여상규수질지표진행감측, 분석료진광층심도적시공특정급기영향인소.연구구역진광층심도공간차이불명현, 단계절변화현저, 동계최고, 하계최저.회귀분석표명광합유효복사(PAR)쇠감계수여투명도、총현부물농도유현저적상관성(R~2 =0.8619, R~2=0.764), 여협록소a상관성불명현(R~2=0.0113).진일보연구분석표명진광층심도、총현부물농도、협록소a주요수소강하구류량、소강회수구수위적영향,복잡적수동력조건여독특적수문조건시영향삼협수고소강회수구진광층심도변화적주요인소.
Spatiotemporal variations of euphotic depth and its causing factors are investigated for the early impounding stage of Three Gorges Reservoir in the backwater area of Xiaojiang River that is a tributary of the Yangtze River. Water samples were taken at five cross-sections in the backwater area during the period May, 2007 through May, 2008. The photosynthetically active radiation (PAR) and conventional water quality monitoring indices were derived from the water samples for analysis in this study. The results show that there are no significant spatial variations in the mean euphotic depth at the five sampling cross-sections. However, seasonal variations are strong with the highest value of euphotic depth in the winter and the lowest value in the summer. Regressions between the attenuation coefficient of PAR with the secchi disc transparency and with the concentration of total suspended solids (TSS) show that the two correlations appeared to be strong as revealed by the coefficient of determination R~2 = 0.8619 for the former and 0.764 for the latter, which indicates that the TSS influence on the euphotic depth is significant. The study also finds that there is no significant correlation between the attenuation coefficient of PAR and the chlorophyll-a (Chla) concentration as shown by the low value of R~2 = 0.0113.This result suggests that the euphotic depth, the concentrations of TSS and Chla are all influenced by the river flow and water stage in the backwater area of Xiaojiang River. The spatiotemporal variation of euphotic depth is thus mainly influenced by the sophisticated hydrodynamic and hydrological conditions in the river-reservoir hybrid system.