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1.
Environ Sci Pollut Res Int ; 31(22): 32746-32765, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38662291

RESUMO

Insufficient freshwater recharge and climate change resulted in seawater intrusion in most of the coastal aquifers in Pakistan. Coastal aquifers represent diverse landcover types with varying spectral properties, making it challenging to extract information about their state hence, such investigation requires a combination of geospatial tools. This study aims to monitor erosion along the major coastal aquifers of Pakistan and propose an approach that combines data fusion into the machine and deep learning image segmentation architectures for the erosion and accretion assessment in seascapes. The analysis demonstrated the image segmentation U-Net with EfficientNet backbone achieved the highest F1 score of 0.93, while ResNet101 achieved the lowest F1 score of 0.77. Resultant erosion maps indicated that Sandspit experiencing erosion at 3.14 km2 area. Indus delta is showing erosion, approximately 143 km2 of land over the past 30 years. Sonmiani has undergone substantial erosion with 52.2 km2 land. Miani Hor has experienced erosion up to 298 km2, Bhuri creek has eroded over 4.11 km2, east Phitii creek over 3.30 km2, and Waddi creek over 3.082 km2 land. Tummi creek demonstrates erosion, at 7.12 km2 of land, and East Khalri creek near Keti Bandar has undergone a measured loss of 5.2 km2 land linked with quantified reduction in the vertical sediment flow from 50 (billion cubic meters) to 10 BCM. Our analysis suggests that intense erosions are primarily a result of reduced sediment flow and climate change. Addressing this issue needs to be prioritized coastal management and climate change mitigation framework in Pakistan to safeguard communities. Leveraging emerging solutions, such as loss and damage financing and the integration of nature-based solutions (NbS), should be prioritized for the revival of the coastal aquifers.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Aprendizado de Máquina , Paquistão , Monitoramento Ambiental/métodos , Erosão do Solo , Mudança Climática
2.
J Hered ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897187

RESUMO

Among the three main divergent lineages of gray wolf (Canis lupus), the Holarctic lineage is the most widespread and best-studied, particularly in North America and Europe. Less is known about Tibetan (also called Himalayan) and Indian wolf lineages in southern Asia, especially in areas surrounding Pakistan where all three lineages are thought to meet. Given the endangered status of the Indian wolf in neighboring India and unclear southwestern boundary of the Tibetan wolf range, we conducted mitochondrial and genome-wide sequencing of wolves from Pakistan and Kyrgyzstan. Sequences of the mitochondrial D-loop region of 81 wolves from Pakistan indicated contact zones between Holarctic and Indian lineages across the northern and western mountains of Pakistan. Reduced-representation genome sequencing of 8 wolves indicated an east-to-west cline of Indian to Holarctic ancestry, consistent with a contact zone between these two lineages in Pakistan. The western boundary of the Tibetan lineage corresponded to the Ladakh region of India's Himalayas with a narrow zone of admixture spanning this boundary from the Karakoram Mountains of northern Pakistan into Ladakh, India. Our results highlight the conservation significance of Pakistan's wolf populations, especially the remaining populations in Sindh and Southern Punjab that represent the highly endangered Indian lineage.

3.
Sci Total Environ ; 880: 163356, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37030381

RESUMO

This study focused on an integrated assessment of coastline change and its impacts on the deltaic sustainability of the Indus Delta, the world's fifth-largest delta. The increase in salinity and degradation of mangrove habitat was examined using multi-temporal Landsat satellite imagery from 1990 to 2020. The tasselled cap transformation indices, multi-statistical End Point Rate and Linear Regression were used to extract the shorelines rates. Mangrove cover area was estimated by applying the Random Forest clasification approach. Impacts of coastal erosion on mangroves and sea-water salinity were determined through the association between electrical conductivity and vegetation soil salinity index (VSSI). The accuracy of the analysis was evaluated using ground truth information obtained from field surveys and Fixed-Point Photography. Major findings of the analysis indicate that the North-West Karachi experienced accretion at an average rate of 7.28 ± 1.15 m/year, with medium salinity (VSSI<0.81) and increased mangrove cover, from 11.0 km2 area in 1990 to 14.5 km2 in 2020. However, the Western Delta has undergone massive erosion at a mean rate of -10.09 ± 1.61 m/year with obtrusive salinity (0.7 ≤ VSSI ≤ 1.2) and 70 km2 of mangrove cover loss. In the Middle West Delta and Middle East Delta erosion is observed at an average rate of -28.45 ± 0.55 m/year rate, with high obtrusive salinity (0.43 ≤ VSSI ≥ 1.32) and rapid mangroves cover loss (14 km2). The Eastern Delta was relatively stable and accelerating towards the sea with increasing mangrove cover (629 km2). Our analysis revealed that erosion, which occured due to reduced sediments flow linked to development of water infrastructures as well as climate change, have serious implications for the ecosystem. Future policy and action-plans should priotitise addressing vulnerabilities by integrate nature-based solutions for revival of the Delta.

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