黄龙山林区位于延安地区东南部,是黄土高原残留植被保存较好的天然次生林区。该区属黄土丘陵山地,以往它除能为国家提供一定数量的木材而外,还对周围地区的农业起着良好的保障作用。为了从生态的角度了解这片森林对涵养水源、保持水土的作用,对陕北高原农业生态系统的建设提供依 Huanglongshan forest is located in the southeastern part of Yan’an, which is a natural secondary forest with better preserved residual vegetation on the Loess Plateau. This area belongs to loess hilly region. In the past, it provided a good quantity of wood for the country and played a good role in safeguarding agriculture in the surrounding area. In order to understand this piece of forest from the ecological point of view to conserve water sources, to maintain the role of water and soil, on the northern plateau agricultural ecosystem construction in accordance with