# Impacts of Harvesting Activities on the Structure of the Intertidal Macrobenthic Community on Lvhua Island, China

## TL;DR

Harvesting on Lvhua Island reduces biodiversity and weakens ecosystem resilience, suggesting the need for protected zones to support both the environment and local communities.

## Contribution

This study integrates ecological surveys and remote sensing to quantify the impact of harvesting on intertidal biodiversity.

## Key findings

- Harvesting hotspots showed reduced biodiversity and signs of species miniaturization.
- Remote sites had higher biomass and diversity compared to disturbed areas near villages.
- RSEI correlated with biodiversity indices and can support cost-effective monitoring.

## Abstract

Understanding the effects of human activities on coastal biodiversity is vital for protecting intertidal ecosystems. On Lvhua Island, many residents harvest shellfish and other marine life, often leading to fewer species and smaller populations in areas near villages. These disturbed sites showed lower ecological stability compared to remote, undisturbed shores, which still supported healthy and diverse communities. Our study shows that frequent harvesting reduces biodiversity and weakens the resilience of the ecosystem. To address this problem, we recommend creating protected zones where harvesting is restricted, giving marine organisms time to recover. Such protection will not only help safeguard the environment but also ensure that fisheries remain a lasting source of food and income for local communities. By balancing conservation with human needs, we can secure both healthy ecosystems and sustainable livelihoods for the future.

Human harvesting exerts significant pressure on intertidal ecosystems, yet its impact on community structure remains insufficiently understood. To assess these effects, we investigated macrobenthic communities on Lvhua Island and adjacent islets by integrating ecological surveys, questionnaire data, and Remote Sensing Ecological Indices (RSEI). We analyzed species composition, biomass, density, and diversity indices across seven sampling sites. Results showed distinct spatial variation: the eastern Lvhua Island exhibited higher biomass and density than the west, with the remote Manduishan islet highest and the South of West Lvhua near the pier the lowest. Harvesting hotspots were dominated by Chlorostoma rusticum and Cantharus cecillei, while less-disturbed islets were characterized by Chl. rusticum, Thais luteostoma, and Turbinidae. Economically valuable gastropods showed signs of miniaturization under intensive harvesting. Biodiversity indices correlated with RSEI, and ABC curve analysis indicated moderate disturbance overall, with the greatest impact at the Donglvhua Bridge site. These findings indicate that a daily subsistence harvest of 100–150 kg resulted in a 31.82% decline in the Shannon-Wiener index, altering the community structure. RSEI provides a cost-effective complement to field monitoring and should be integrated into management frameworks to support both ecological conservation and community livelihoods.