Table 1 Screening for key indicators related to degradation of ecosystem in BYD Lake.

Climate change

Air temperature

°c

It is directly related to water temperature, the most crucial driving force on species’ metabolism and dynamics.

Precipitation

mm

It affects hydrology and water quality

Wind speed

m/s

It affects the spatial distribution of plankton¹⁴

Hydrological conditions^a

Inflow

m³/s

It affects the hydrological cycle, water quantity, water quality, and ecological balance¹⁰.

Water level

m

It affects the distribution of submerged vegetation and benthos

Anthropogenic pollution^b

Total nitrogen

mg/L

The main factor influencing species richness of phytoplankton, macrophytes, zooplankton, and benthos.

Total phosphorus

mg/L

The main driving force of eutrophication is phosphorus, which is the limiting nutrient in BYD Lake³⁷.

Secchi depth

cm

It affects the photosynthesis of aquatic plants

Dissolved oxygen

mg/L

It affects the cycles of carbon, nitrogen, and phosphorus and maintains biological respiration and metabolism¹⁶.