一、课题缘起丁字湾位于山东省胶东半岛西南岸,西南距胶州湾约60千米。海湾主体呈北西—南东走向的“丁”字形,湾内岸线蜿蜒曲折,岬湾相间,湾顶部在麻姑岛附近折而向西南方向延伸,湾口则转向东南方向,形成狭长的半封闭状海湾。湾口最宽处12.3千米,从湾口到湾顶长约22千米,水域面积约144平方千米。海湾周围被山地丘陵环抱,海拔多在70米左右,为火山岩及沉积岩构成的剥蚀山丘和切割坡地,表面覆盖的残积—坡积土较薄。注入丁字湾的河流较多较小,最大者为西北部的五龙河,其次有白沙河、贤友 First, the subject of Ding River Bay is located in Shandong Province, Shandong Peninsula southwest coast, southwest from Jiaozhou Bay about 60 km. The main body of the gulf is in the shape of “Ding” in the northwest-south east. The inner shores of the bay are meandering and twisting along the promontory. The top of the bay is folded southwest of Magu Island, while the bayou is southeast. Semi-enclosed bay. The widest point of the mouth 12.3 km, from the bayou to the bay top about 22 km, the water area of ​​about 144 square kilometers. Around the bay surrounded by mountains and hills, mostly at an elevation of about 70 meters, composed of volcanic rocks and sedimentary denuded hills and cutting slope, the surface coverage of the residual slope soil is thin. The rivers infused into T-Bay are more smaller, with the largest being the Wulong River in the northwest, followed by the Baisha River and Xiangyou