Branched　glycerol　dialkyl　glycerol　tetraethers　(brGDGTs)　are　potentially　valuable　biomarkers　for　paleoclimatic　and　paleoenvironmental　studies.　However,　multiple　factors　controlling　their　variations　in　lake　sediments　hamper　the　widespread　application　of　brGDGT-based　proxies.　Here　we　investigate　brGDGTs　in　water　column　suspended　particulate　matter　(SPM)　and　surface　sediments　in　a　series　of　lakes　with　a　wide　range　of　depths　from　three　main　volcanic　fields　of　northeastern　China.　The　brGDGT　distribution　patterns　from　SPM　and　surface　sediments　of　these　lakes　differ　greatly　from　those　of　surrounding　soils,　indicating　a　predominant　aquatic　origin　for　brGDGTs.　We　find　that　the　ratio　of　5-methyl　hexamethylated　and　pentamethylated　brGDGTs　with　no　cyclopentane　rings　(IIIa/(IIa　+　IIIa);　designated　as　HP5)　is　strongly　correlated　with　water　depth.　Re-examination　of　published　brGDGT　data　from　SPM　samples　in　redox-stratified　Lake　Lugano　reveals　similar　relationships,　whereas　such　correlations　are　much　weaker　in　Lake　Superior　which　does　not　have　an　anoxic　hypolimnion.　Importantly,　we　find　that　there　is　strong　correlation　between　HP5　and　dissolved　oxygen　in　water　column　of　the　redox-stratified　lakes,　suggesting　that　the　observed　apparent　HP5–water　depth　correlation　may　be　primarily　attributed　to　depth-progressive　shifts　in　the　brGDGT-producing　bacterial　communities　with　different　redox　requirements　(aerobic,　facultative　anaerobic,　and　anaerobic　bacteria).　Notably,　brGDGT　methylation　indices　(MBT5ME　and　MBT6ME)　of　surface　sediments　display　poor　correlations　with　air　temperatures　in　our　study　lakes,　calling　for　caution　in　applying　MBT5ME　and　MBT6ME　as　temperature　proxies　in　these　lakes.　©　2020　Elsevier　Ltd