# Satellite‐Driven Synthesis of Fish Production Dynamics and Carrying Capacity Mechanisms in a High‐Altitude Lake Ecosystem

## TL;DR

This study uses satellite data to assess fish production and carrying capacity in Qinghai Lake, showing how energy availability affects fish populations and guiding sustainable management.

## Contribution

A novel satellite-based framework integrating MODIS data and a production model to assess fish potential production and carrying capacity in a high-altitude lake.

## Key findings

- Fish production in Qinghai Lake increased 50-fold from 2002 to 2024, driven by rising primary production.
- Fish Potential Production (FPP) peaks in summer and is highest near riverbanks, while central lake areas remain low.
- The Fish Carrying Capacity Index (FCCI) indicates that restocking should focus on underutilized southeastern regions to relieve pressure on the northwest.

## Abstract

Understanding how limited energy constrains fish populations in fragile high‐altitude lakes is essential for sustainable fisheries management. This study developed a satellite‐based framework that integrated MODIS‐derived chlorophyll a data with a vertically generalised production model. This framework was used to map Fish Potential Production (FPP) and establish a novel Fish Carrying Capacity Index (FCCI) for the endemic naked carp (
Gymnocypris przewalskii
) in Qinghai Lake, China, from 2002 to 2024. Over the 23‐year period, lake‐wide fish production increased 50‐fold (from 2592 to 127,500 t) alongside an upward trend in FPP driven by primary production. Seasonally, FPP per unit area peaked in summer (July–August: 30–50 g/m2) and declined in spring (May–June: 0–30 g/m2). Spatially, the highest values occurred near riverbank and tributary estuaries, whereas central waters remained low. The FCCI revealed significant heterogeneity; the northwestern regions experienced high food demand pressure (FCCI > 0.5), while the southeastern areas were underutilised (FCCI < 0.3). As the lake‐wide FCCI never exceeded 0.6, the current level of primary productivity can support further strategic restocking, provided that releases are redirected to the southeast to relieve pressure on the northwest. This study demonstrates how remote sensing can be used to balance fish conservation and production goals in sensitive plateau ecosystems.

This study evaluates fish potential production (FPP) and fish carrying capacity index (FCCI) in Qinghai Lake using satellite‐based primary production estimates. Results show increasing FPP trends and spatially heterogeneous FCCI, indicating potential for sustainable fisheries management and guiding restocking efforts in this high‐altitude lake ecosystem.