黄土高原地区历史上植被情况如何,有没有森林?多少年来,不少专家学者从各个角度进行过深入的研究,做了大量的工作。但至今未形成统一的意见。而对于沙漠广布、植被稀疏的毛乌素的森林之说,更是认识不一。 侯仁之院士和朱士光先生多次深入实地从历史地理的角度进行调查研究,认为“陕北与内蒙古伊克昭盟之间 In the past few years, many experts and scholars conducted in-depth research from all angles and did a great deal of work. But so far no unified opinion has been formed. And for the widespread and sparsely populated forests of Muowu, it is even more disparaging. Academician Hou Renzhi and Mr. Zhu Shiguang conducted in-depth and in-depth investigations and studies from the perspective of history and geography. They held that "between North Shaanxi and the Ikchuk League in Inner Mongolia