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Organochlorine compounds pose health risks to the Qinling Giant Panda (Ailuropoda melanoleuca qinlingensis)
2021
Zhao, Yan | Chen, Yiping | Macdonald, David W. | Li, Jun | Ma, Qing-yi
To assess organochlorine compound (OC) contamination, its possible sources, and adverse health impacts on giant pandas, we collected soil, bamboo, and panda fecal samples from the habitat and research center of the Qinling panda (Ailuropoda melanoleuca qinlingensis)—the rarest recognized panda subspecies. The polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) concentrations were comparatively low which suggests that moderate sources of OC pollution currently. OC levels were lower in samples from nature reserve than in those collected from pandas held in captivity, and OC levels within the reserve increased between functional areas in the order: core, buffer and experimental. The distribution patterns, and correlation analyses, combined with congener distributions suggested PCBs and OCPs originated from similar sources, were dispersed by similar processes, being transported through atmosphere and characterized by historical residues. Backward trajectory analyses results, and detected DRINs (aldrin, dieldrin, endrin and isodrin) both suggest long-range atmospheric transport of pollution source. PCBs pose potential cancer risk, and PCB 126 was the most notable toxicant as assessed be the high carcinogenic risk index. We provide data for health risk assessment that can guide the identification of priority congeners, and recommend a long-term monitoring plan. This study proposes an approach to ecotoxicological threats whereby giant pandas may be used as sentinel species for other threatened or endangered mammals. By highlighting the risks of long-distance transmission of pollutants, the study emphasizes the importance of transboundary cooperation to safeguard biodiversity.
Afficher plus [+] Moins [-]Lighting up our waterways: Impacts of a current mitigation strategy on riparian bats
2022
Hooker, Jack | Lintott, Paul | Stone, Emma
Increasing levels of artificial light at night (ALAN) are a major threat to global biodiversity and can have negative impacts on a wide variety of organisms and their ecosystems. Nocturnal species such as bats are highly vulnerable to the detrimental effects of ALAN. A variety of lighting management strategies have been adopted to minimise the impacts of ALAN on wildlife, however relatively little is known about their effectiveness. Using an experimental approach, we provide the first evidence of negative impacts of part-night lighting (PNL) strategies on bats. Feeding activity of Myotis spp. was reduced along rivers exposed to PNL despite no reduction in overall bat activity. We also provide the first evidence of negative effects of PNL on both feeding and activity for Pipistrellus pipistrellus which has previously been recorded feeding under artificial light. Despite having considerable energy-saving benefits, we outline the potential negative impacts of PNL schemes for bats in riparian habitats. PNL are unlikely to provide desired conservation outcomes for bats, and can potentially fragment important foraging habitats leading to a breakdown of functional connectivity across the landscape. We highlight the potential dichotomy for strategies which attempt to simultaneously address climate change and biodiversity loss and recommend alternative management strategies to limit the impacts of ALAN on biodiversity.
Afficher plus [+] Moins [-]Community-based adaptation to climate change in villages of Western Province, Solomon Islands
2020
Basel, Britt | Goby, Gillian | Johnson, Johanna
People, local cultures and the environments they live in are complex and dynamic social-ecological systems that have evolved together over time and are continually affected by a myriad of factors, including climate and global changes. Escalating climate and global changes present an imminent threat to Pacific communities, particularly for food security, livelihoods, health and safety, cultural identity and biodiversity conservation. A participatory community-based climate change adaptation planning process was used to engage with communities on Rendova Island in Western Province, Solomon Islands to identify local adaptation priorities. The methodology recognized that local community members are the managers of the resources they use daily, have direct knowledge of the status of key local resources and have direct influence over ongoing resource governance. The study focused on two objectives: (1) identifying community priorities and documenting them in adaptation plans intended for local implementation, and (2) evaluating whether community adaptation priorities addressed key vulnerabilities identified independently using a semi-quantitative vulnerability assessment.The adaptation priorities identified by the communities encompassed: governance, leadership and planning; farming and livestock; sustainable livelihoods; natural resource management; and youth capacity building. The community adaptation priorities were found to address the key climate change vulnerabilities identified in the semi-quantitative assessment and also addressed additional drivers of social vulnerability and adaptive capacity. This finding reiterates the importance of fully inclusive and participatory vulnerability assessments and community-identification of adaptation priorities coupled with scientific climate projections to comprehensively assess the complexity of social-ecological systems. The climate change adaptation priorities have informed ongoing local actions and are intended to be used by communities, government and NGOs to focus local effort, funding and project development. A review of the suitability of the adaptation priorities by similar villages on neighbouring islands would determine the utility of scaling-up and applying these adaptations to other rural communities in the Solomon Islands, and possibly more widely in other Pacific communities.
Afficher plus [+] Moins [-]Provision of refugia and seeding with native bivalves can enhance biodiversity on vertical seawalls
2020
Bradford, Thea E. | Astudillo, Juan C. | Lau, Edward T.C. | Perkins, Matthew J. | Lo, Chi C. | Li, Tom C.H. | Lam, Chung S. | Ng, Terence P.T. | Strain, Elisabeth M.A. | Steinberg, Peter D. | Leung, Kenneth M.Y.
Recent studies have suggested that increasing habitat complexity of artificial seawalls by modifying surface heterogeneity could enhance exploitable habitat and therefore species richness and abundance. We tested the effects of adding complex tiles (with crevices/ledges) of different heterogeneity (i.e., flat tiles resembling the seawall vs. tiles with crevices of 2.5 cm or 5.0 cm depth) and seeding with native rock oysters, Saccostrea cuccullata (unseeded vs. seeded) on species richness and abundances of intertidal marine organisms on two vertical seawalls in Hong Kong. Tiles were affixed to the mid-intertidal zone of the seawalls for 12 months. The results showed that the tiles with crevices had greater species richness and cover of sessile epifauna than flat tiles. Seeding tiles with S. cuccullata also facilitated natural recruitment of the same species. Our results support the hypothesis that using eco-engineering to increase habitat complexity can enhance the biodiversity of intertidal marine organisms on seawalls.
Afficher plus [+] Moins [-]COVID-19 lockdown improved the health of coastal environment and enhanced the population of reef-fish
2021
Patterson Edward, J.K. | Jayanthi, M. | Malleshappa, H. | Immaculate Jeyasanta, K. | Laju, R.L. | Patterson, Jamila | Diraviya Raj, K. | Mathews, G. | Marimuthu, A.S. | Grimsditch, Gabriel
Reduction in the impact of human-induced factors is capable of enhancing the environmental health. In view of COVID-19 pandemic, lockdowns were imposed in India. Travel, fishing, tourism and religious activities were halted, while domestic and industrial activities were restricted. Comparison of the pre- and post-lockdown data shows that water parameters such as turbidity, nutrient concentration and microbial levels have come down from pre- to post-lockdown period, and parameters such as dissolved oxygen levels, phytoplankton and fish densities have improved. The concentration of macroplastics has also dropped from the range of 138 ± 4.12 and 616 ± 12.48 items/100 m² to 63 ± 3.92 and 347 ± 8.06 items/100 m². Fish density in the reef areas has increased from 406 no. 250 m⁻² to 510 no. 250 m⁻². The study allows an insight into the benefits of effective enforcement of various eco-protection regulations and proper management of the marine ecosystems to revive their health for biodiversity conservation and sustainable utilization.
Afficher plus [+] Moins [-]Water quality assessment of the ecologically stressed Hooghly River Estuary, India: A multivariate approach
2018
Mitra, Soumita | Ghosh, Swayambhu | Satpathy, Kamala Kanta | Bhattacharya, Bhaskar Deb | Sarkar, Santosh Kumar | Mishra, Pravakar | Rājjā,
Spatio-temporal and seasonal variation of the water quality characteristics of the Hooghly River Estuary, India were studied considering eight stations of diverse eco-hydrological characteristics. Wide variations in turbidity, total dissolved solids and fecal coliform exceeded the permissible BIS drinking water level limit. The estuary is observed to be relatively low-oxygenated, mesotropic and phosphate limiting. Spatial heterogeneity and impact of the southwest monsoon were remarkably pronounced in the distribution of the inorganic nutrients revealing the following values (expressed in μgatml−1): nitrate+nitrite (2.42–37.19), phosphate (0.41–1.52) and silicate (38.5–187.75). Water Quality Index (WQI) values confirmed the prevailing ‘bad’ condition, detrimental for sustenance of aquatic biota. Results of Principal Component Analysis identified the major factors liable for water quality deterioration while cluster analysis categorized the stations on the basis of similar water quality status. The authors recommend adopting preventive measures for water quality improvement linked to biodiversity conservation.
Afficher plus [+] Moins [-]Marine protected communities against biological invasions: A case study from an offshore island
2017
Gestoso, I. | Ramalhosa, P. | Oliveira, P. | Canning-Clode, J.
Biological invasions are a major threat to the world's biota and are considered a major cause of biodiversity loss. Therefore, world marine policy has recognized the need for more marine protected areas (MPAs) as a major tool for biodiversity conservation. The present work experimentally evaluated how protected communities from an offshore island can face the settlement and/or expansion of nonindigenous species (NIS). First, NIS colonization success in marine protected and marina communities was compared by deploying PVC settling plates at the Garajau MPA and Funchal marina (SW Madeira Island). Then, the settling plates from the MPA were transferred to Funchal marina to test their resistance to NIS invasion under high levels of NIS pressure. Results indicated that the structure and composition of fouling communities from the MPA differed from those collected in the marina. Interestingly, communities from the protected area showed lower NIS colonization success, suggesting some degree of biotic resistance against NIS invasion.
Afficher plus [+] Moins [-]Commercially important species associated with horse mussel (Modiolus modiolus) biogenic reefs: A priority habitat for nature conservation and fisheries benefits
2017
Kent, Flora E.A. | Mair, J. M. (James M.) | Newton, Jason | Lindenbaum, Charles | Porter, Joanne S. | Sanderson, William G.
Horse mussel reefs (Modiolus modiolus) are biodiversity hotspots afforded protection by Marine Protected Areas (MPAs) in the NE Atlantic. In this study, horse mussel reefs, cobble habitats and sandy habitats were assessed using underwater visual census and drop-down video techniques in three UK regions. Megafauna were enumerated, differences in community composition and individual species abundances were analysed. Samples of conspicuous megafauna were also collected from horse mussel reefs in Orkney for stable isotope analysis.Communities of conspicuous megafauna were different between horse mussel habitats and other habitats throughout their range. Three commercially important species: whelks (Buccinum undatum), queen scallops (Aequipecten opercularis) and spider crabs (Maja brachydactyla) were significantly more abundant (by as much as 20 times) on horse mussel reefs than elsewhere. Isotopic analysis provided insights into their trophic relationship with the horse mussel reef. Protection of M. modiolus habitat can achieve biodiversity conservation objectives whilst benefiting fisheries also.
Afficher plus [+] Moins [-]Identifying the ecological security patterns of the Three Gorges Reservoir Region, China
2022
Dai, Yunchuan
Identifying and improving the existing ecological security patterns (ESPs) are of great importance to promoting ecological security and achieving sustainable development goals. The Three Gorges Reservoir Region (TGRR) is an area with a sensitive, fragile, and complex ecological environment in the Upper Reaches of the Yangtze River. The construction of ESPs for the TGRR is significant for maintaining regional ecosystem stability and promoting peaceful coexistence between humans and nature. The main objective of the study is to identify the ecological nodes, ecological corridors, and ecological sources that play essential roles in the ecosystem. Based on land use data and human interference factors, we have evaluated the current habitat quality using the InVEST model and identified vital ecological sources for the TGRR. The negative exponential transformation function was used to convert habitat suitability into a landscape resistance layer. Circuit theory modeling was utilized to identify ecological corridors, and the final ESPs of the TGRR were then constructed. Results showed that (a) the spatial distribution of habitat varied significantly in the TGRR. The optimal habitats were concentrated in the northeast, east, and southwest, accounting for 45.98% of the total suitable habitats; (b) habitat quality varied through space, with habitat quality being higher in the northeast and lower in the western regions. (c) Ecological sources were distributed primarily in the forests with high vegetation coverage in the east. The total area of ecological sources was about 15,412 km², approximately accounting for 34% of the study area; (d) the ESPs were dominated by ecological sources composed of forests, which were radially connected by ecological corridors. In total, these included 14 significant ecological sources, 25 clusters of ecological corridors, and 23 ecological nodes. The results are of great significance to promote the ecological security of the TGRR and could provide theoretical support for biodiversity conservation and territorial space planning for the Three Gorges Region.
Afficher plus [+] Moins [-]Empirical study of the coupling relationship between biodiversity and environmental geology under different ecological status: Evidence from five typical areas in Guizhou, China
2022
Xie, Yuangui | Zhang, Lanyue | Gong, Xingxiang | Liu, Jiming | Liao, Xiaofeng | Dong, Yanyan
Analyzing the coupling relationship between biodiversity and environmental geology and exploring the factors affecting the coupling degree are of vital significance for the protection and restoration of the ecological environment. In this study, we selected five typical areas (i.e., Caohai, Chishui, Fanjingshan, Maolan, and Guanshanhu) to represent the whole Guizhou Province, China. Based on the coupling coordination degree model, we analyzed their coupling coordination trend. The results showed that the coordinated development stages of the Chishui and Fanjingshan areas both could be categorized as the synchronous development type of primary coordination because of their excellent nature conditions; the Maolan area was categorized as having restrained environmental geology because of its weak environmental geology condition; and the Guanshanhu and Weining areas were strongly affected by human activities, and both could be categorized as having restrained biodiversity. In combination with practical situation, Guizhou province can be categorized into the following three zones: an original ecological zone, a zone with fragile ecological environment, and a zone affected by human activities. Biodiversity conservation measures should be proposed according to the specific ecological situation of these different zones. In this way, the harmonious coexistence of economic development and the ecological environment can be realized.
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