黄龙山、乔山南部的丘陵山地,覆盖着广袤的天然森林植被,它是黄土高原上的一块“绿洲”。经过30多年来的保护、封育、造林、抚育和改造,这块“绿洲”已更加葱郁。随着事物的发展,人们的认识和要求也在发展。在新的形势下,有必要对渭北丘陵山地的天然次生林重新进行评价,并提出提高经营水平的新要求。 Huanglong Mountain, Qiaoshan southern hills and mountains, covered with vast natural forest vegetation, it is an “oasis” on the Loess Plateau. After more than 30 years of protection, enclosure, reforestation, tending and transformation, this “oasis” has become even more lush. With the development of things, people’s understanding and requirements are also developing. Under the new situation, it is necessary to re-evaluate the natural secondary forests in the hilly areas of Weibei and propose new requirements for improving the management level.