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中文摘要：
认识云贵高原的环境变化在局地、区域和全球三个层面上具有重要意义。不同湖泊沉积物-水界面的生物地球化学过程具有重要差别，因而其水源保护途径也不尽相同。a．贵州阿哈湖汇水区煤矿开采导致EFe-Mn在沉积物中积累并产生季节性二次污染。缺氧季节硫酸盐还原作用上移至沉积物顶部，导致界面亚扩散层对Fe^2＋的屏蔽，Fe-Mn循环受沉积物-水地质界面和氧化-还原化学界面的双重控制。控制Fe—Mn释放和降低入湖通量、选取优质水区和清淤处理是污染控制的有效途径。b．1994年秋贵州百花湖出现“突发性”水质恶化，剖析相互关联水质指标表明：“湖泊黑潮”是特定季节、特殊气候条件下，沉积有机质生物氧化作用的耦合；脱氮过程受阻的pH控制导致亚硝酸根浓度增高。随着水体耗氧-复氧平衡、水流输送及天气好转，水质可望在一段时期内复苏。后期观测表明了水质的好转。c．云南洱海沉积物平均堆积速率为0．047g·cm^-2·a^-1；沉积物顶部几厘米Pb稳定同位素组成表明其铅来源稳定；沉积有机质主要为陆源，早期成岩过程Corg垂直剖面具“沉降-降解-堆积”三阶段分布。近460年间，δ^13Corg小幅度频繁波动及δ^13Cinoxrg和δ^18Oinorg同步降低的总趋势表明汇水区人为活动的明显影响。控制陆源有机质的输入通量是保护洱海的基本策略。d．云南程海是一个湖水离子总浓度接近盐湖下限的中度富营养湖泊。沉积物Horg／Corg和Corg／Norg原子比率表明其有机质主要源于内生浮游藻类残骸；沉积记录中^210Pbex与Corg的沉积通量显示出良好的同步关系。特别是二者同步增大时段表明：^210Pbex沉积通量增加指示湖泊初级生产力增大，这种微粒清洗效应反映了湖泊自然作用对富营养演化的调控作用。
英文摘要：
It is of local, regional and global importance to understand the environmental changes on the Yunnan-Guizhou Plateau. Difference on bio-geochemical process of the sediment-water interface exists among lakes so that protection approaches to water resources vary. a. The coal mining in the catchment of Lake Aha causes FeMn accumulation in the sediment leading to the seasonal secondary pollution. In anoxic condition, the sulphate deoxidization migrates to the upper layer of sediments which results in Fe^2＋ screening of the diffusive boundary layer. The Fe-Mn cycling is controlled by both the sediment-water geological interface and oxidation-reduction chemical interface. Controlling Fe-Mn release and reducing their flux into the lake, selecting good-quality water district and cleaning sludge are efficient ways to control pollutions, b. Paroxysmal deterioration of water quality in Lake Baihua appeared in autumn, 1994 in Guizhou. Analysis of incident cross-correlation water-quality indicators indicated that the ＂Lake Black Tide＂ resulted from the coupling of bio-oxidation of depositional organic matters under the specific season and climatic conditions; pH-restraint of de-nitric process led to increase in NO2^- concentration. The water quality was expected to recover in times with the balancing of oxygen in waters, input of water flow and better weather conditions. This was confirmed by the late monitoring, c. The average sedimentation rate of Lake Erhai is 01 047 g · cm^2 · a^-1. The Pb-isotopic compositions of recent sediments indicate that may have a stable source. The depositional organic matter originates mainly Irom me lanu. In the chemical processes of early diagenesis, the Corg vertical profiles of sediments show three stages ＂Deposition-Decomposition-Accumulation＂. In the last 460 years, small-scope frequent fluctuation of δ^13 Cinorg and synchronically decreasing trends of δ^13Cinorg and δ^18Oinorg indicate an obvious influence of human activity in the catchment. Control of input flux of te
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