effective population size

例句：

1. 1. The government is considering a new policy to reduce the effective population size of the city.
   政府正在考虑一项新政策，以减少城市的有效人口规模。
2. 2.The study found that the effective population size had decreased significantly in recent years.
   研究发现，近年来有效人口规模已经显著下降。
3. 3.The effective population size is an important factor in determining the sustainability of a community.
   有效人口规模是决定社区可持续性的一个重要因素。