Balearica pavonina Biodiversity Birds China Climate change Conservation management Diversity Ecosystem health Ecosystems Environmental change Estuaries Liaohe Estuary Liaohe estuary Liaoning Non-metric multi-dimensional scaling Nonmetric multi-dimensional scaling Nonmetric multi-dimensional scaling (NMS) Population distribution Population statistics Red-crowned Crane Red-crowned cranes Saunders gull Saunders's Gull Waterbird Waterbirds abundance biodiversity climate change economic diversification migratory behavior