天津市蓟县山区,地势北高南低,海拔一般在100—500米之间,最高峰云摩洞1078米。成土母岩多为石灰岩,少为砂岩、页岩、花岗岩。山坡多为瘠薄的多石砾土。土层厚度仅有15—30厘米(纯土壤层不过2—3厘米),坡度在26—43度之间。海拔300米以上山坡分布的原生植被多是黄白草、鼠李菜;300米以下多是羊胡子草、酸枣等植物。由于石多土薄加之大陆性季风气候,冬季寒冷干燥,夏季炎热多雨,春秋干旱多风 Jixian County, Tianjin Mountain, the topography of North High South Low, generally 100-500 meters above sea level, the highest peak of 1078 meters Mount Morrow. Into the mother rock mostly limestone, less sandstone, shale, granite. Hillside mostly barren rocky soil. Soil thickness of only 15-30 cm (pure soil layer but 2-3 cm), the slope of 26-43 degrees. More than 300 meters above sea level slope distribution of the native vegetation are mostly yellow and white grass, walnuts cabbage; more than 300 meters Cotton grass, jujube and other plants. Due to the multi-soil thin continental continental monsoon climate, cold and dry in winter, hot and humid in summer, spring and autumn drought windy