北京昌平：生态好 鸟儿至

Group 1 - The article highlights the ecological improvements in Beijing's Changping District, emphasizing the increase in bird populations as a positive indicator of environmental health [1][2][3] - It discusses various conservation efforts undertaken in the region, which have contributed to the enhancement of local biodiversity [4][5] - The article notes specific species of birds that have returned to the area, showcasing the success of these ecological initiatives [6][7]