Currently, global climate change and oil pollution are two main environmental concerns for sea cucumber (Apostichopus japonicus) aquaculture. However, no study has been conducted on the combined effects of elevated temperature and oil pollution on sea cucumber. Therefore, in the present study, we treated sea cucumber with elevated temperature (26 °C) alone, water-accommodated fractions (WAF) of Oman crude oil at an optimal temperature of 16 °C, and Oman crude oil WAF at an elevated temperature of 26 °C for 24 h. Results showed that reactive oxygen species (ROS) level and total antioxidant capacity in WAF at 26 °C treatment were higher than that in WAF at 16 °C treatment, as evidenced by 6.03- and 1.31-fold-higher values, respectively. Oxidative damage assessments manifested that WAF at 26 °C treatment caused much severer oxidative damage of the biomacromolecules (including DNA, proteins, and lipids) than 26 °C or WAF at 16 °C treatments did. Moreover, compared to 26 °C or WAF at 16 °C treatments, WAF at 26 °C treatment induced a significant increase in cellular apoptosis by detecting the caspase-3 activity. Our results revealed that co-exposure to elevated temperature and crude oil could simulate higher ROS levels and subsequently cause much severer oxidative damage and cellular apoptosis than crude oil alone on sea cucumber.

Sea cucumber (Apostichopus japonicus) is mainly cultured in the coastal zone, where it is easily threatened by accidental oil spills. Chemical dispersant is one of the efficient oil spill responses for mitigating the overall environmental damage of oil spills. However, the impact of crude oil and chemical dispersants on sea cucumber is less well known. Hence, the present study focused on exploring the antioxidant response and oxidative stress in the respiratory tree of sea cucumber following exposure to GM-2 chemical dispersant (DISP), water-accommodated fractions (WAF), and chemically enhanced WAF (CEWAF) of Oman crude oil for 24 h. Results manifested that WAF exposure caused a significant increase in the reactive oxygen species (ROS) level (5.29 ± 0.30 AU·mgprot⁻¹), and the effect was much more obvious in CEWAF treatment (5.73 ± 0.16 AU·mgprot⁻¹). Total antioxidant capacity (T-AOC), as an important biomarker of the antioxidant defense capacity, showed an increasing trend following WAF exposure (0.95 ± 0.12 U·mgprot⁻¹) while a significant reduction in T-AOC was observed following CEWAF exposure (0.23 ± 0.13 U·mgprot⁻¹). Moreover, we also evaluated the oxidative damage of the macromolecules (DNA, protein, and lipid), and our results revealed that the presence of chemical dispersant enhanced oxidative damage caused by crude oil to sea cucumber.

Rapid urbanization has intensified ecological problems such as landscape fragmentation and biodiversity decline, underscoring the need to maintain regional ecological integrity. The construction of ecological security patterns and the optimization of ecological restoration areas are crucial for addressing these ecological issues. However, research on how to couple ecological security patterns with ecological risk assessment to scientifically identify priority areas for ecological restoration and guide spatially targeted restoration remains insufficient. To address this gap, we investigated Liaoning Province by integrating morphological spatial pattern analysis, landscape connectivity assessment, and ecosystem service hotspot analysis to identify ecological sources. We then applied the minimum cumulative resistance model and circuit theory to extract ecological corridors, constructing a comprehensive ecological security pattern. Integrating landscape ecological risk assessment with ecological security patterns established a conservation and restoration-oriented ecological security framework. The results show that the ecological security pattern comprises 40 ecological source patches and 89 potential ecological corridors. Ecological sources encompass a total of 17,628 km² (approximately 12% of the province), primarily comprising water bodies, grasslands, shrublands, and forests. The ecological corridors span a total of 3533.9 km, with an average length of 39.7 km. We also identified 139 ecological pinch points and 109 ecological barrier points. Integrating these findings with landscape ecological risk zoning delineates ecological restoration zones, revealing a spatial pattern characterized by east–west differentiation and north–south continuity. This ecological conservation and restoration network provides a clear spatial guide and a robust scientific foundation for territorial spatial planning, ecological conservation, and restoration efforts.

Artificial reefs have been advocated and implemented as management tools for aquaculture, species conservation and habitat replacement. However, the shelter capacity of artificial reefs and its influencing factors are still not well understood. In this study, we identified factors that may limit the shelter capacity of artificial reefs for sea cucumber (Apostichopus japonicas) with a laboratory experiment. We investigated how water flow and food availability affect the shelter capacity and conducted shelter utilization experiments to determine whether sea cucumber sheltering behavior was density dependent. The results revealed that shelter capacity of artificial reefs in high velocity is significantly higher than that of artificial reefs in low velocity or no velocity. The artificial reefs that were provided food had significantly higher shelter capacity than those that did not have food. The densities did not affect the sheltering capacity of artificial reefs in the laboratory experiment. There was a logarithmic relationship between the shelter capacity and shelter availability assessed by the exposed surface area of the artificial reefs. In conclusion, abundant food resources and high water flow may have a positive effect on the shelter capacity of artificial reefs.

The spotted seal (Phoca largha), the only pinniped species capable of natural breeding in Chinese waters, serves as a flagship species for the Bohai Sea and the Yellow Sea marine ecosystems. Changes in its population numbers are an important indicator of the status of the marine ecological environment. However, when using traditional monitoring methods, such as telescope inspections and routine unmanned aerial vehicle (UAV) photography, it is difficult to accurately grasp the changes in spotted seal populations. Here, we document the use of infrared imaging with a UAV to facilitate round-the-clock monitoring of spotted seal numbers in a protected area. This approach revealed that late night and early morning (22:00–05:00) were peak times for their haul-out activity, with a maximum count of 166. This provides a new idea for the investigation and monitoring of marine mammals and the protection of marine ecosystems.