京哈铁路从黑龙江省中部穿过,将其分为东西两部分,本文所说的黑龙江东部地区,大体上就是这条铁路以东的那部分区域。小兴安岭、张广才岭、老爷岭成为这一区域与其他区域的地理分界。这一地区的自然地貌可以分为两大部分,一部分是松花江、乌苏里江、黑龙江三条河流流经的平原地区,另一部分是低山丘陵和河谷地区。这一区 The Beijing-Harbin Railway runs through the central Heilongjiang Province and is divided into two parts. The eastern part of Heilongjiang described in this paper is generally the area to the east of this railway. Xiaoxinganling, Zhang Guangcai Ridge, Laoyeling become the geographical boundaries of this region and other regions. The natural landform in this area can be divided into two parts, one part is the plains through which Songhua, Wusuli and Heilongjiang rivers flow, and the other part is the hilly and valley areas. This area