Sajid Rashid Ahmad

Municipal solid waste (MSW) continues to generate polluted gases, toxic leachate, and thermal emissions even after landfill closure. This study evaluates long-term bio-hazard, thermal, and moisture impacts of MSW using 9 years of satellite observations for the functional phase (FP) and post-functional phase (PFP) of a dumping site in Multan, Pakistan. The average annual radius of bio, thermal, and moisture influence zones during FP was 1097 m, 1454 m, and 1248 m, respectively, increasing to 1249 m, 1504 m, and 1470 m in PFP. Seasonal analysis showed rising trends during FP and declining trends in PFP. The novelty of this study lies in combining the multi-index remote sensing, zonal proximity, and trend-detection techniques to distinguish environmental reactions between FP and PFP. The findings provide evidence-based spatial hazard thresholds and demonstrate the long-term value of remote sensing in characterizing persistent landfill impacts. Mann–Kendall and innovative trend analysis were applied to detect temporal trend variations. Overall, this work offers a cost-effective, scalable, and reliable approach for monitoring environmental risks from MSW and supports improved landfill management strategies. This study significantly offers a cost-effective, scalable, and reliable approach for monitoring environmental risks from MSW and supports improved landfill management strategies.

Microplastic (MP) pollution has become a global environmental concern due to its ubiquitous presence and potential threats to ecosystems. Cetaceans, as top predators, have served as sentinel species for monitoring ecosystem changes and as flagship species for establishing environmental conservation strategies. Here, we investigated MPs for the first time in the complete gastrointestinal tract of five individuals of an endangered Indus River dolphins (Platanista minor) stranded along the Indus River from 2019−2022. MPs were detected from all examined specimens with an average of 286.4 ± 109.1 MPs per individual, indicating the potential pathways for the accumulation of MPs due to prey consumption and unintentional ingestion during food uptake in Indus River dolphin. The properties of MPs demonstrated that the most prevalent shapes were fibers, with sizes mostly ranging from 5 mm-300µm. Polyethylene terephthalate (PET) was the predominant composition identified via FT-IR spectroscopy. Moreover, the prevalence of MPs observed in the small intestine was higher than in other parts due to length and structure. This is the first study to highlight the ecological risks posed by MP polymers through a polymer risk assessment (H) showing medium (Level III) to high risks (Level IV) to Indus River dolphins. This study represents the first baseline assessment of MPs pollution caused by anthropogenic activities and offers valuable insights for the conservation of this endangered freshwater species. Our results emphasize the need for further ecotoxicological studies to better understand the potential impacts of MPs in this endangered species.

To investigate the seasonal and temporal variations of environmental impacts surrounding the municipal solid waste (MSW) dumping site in Bahawalpur, the study accomplished spatiotemporal analysis for three satellite-based indicators: bio indicators (B-Is), thermal indicators (T-I), and moisture indicators (M-I) over 7 years of data acquired using a space-based platform from 2015 to 2021. The average annual expansions of bio-, thermal-, and moisture-influenced zones are 1114, 1158, and 1129 m with severity range averages to 0.07, 2.96, and 0.07 respectively. The seasonal averages of bio-influenced zone are 1341, 1277, 1151, 1103, 1044, and 779 m; thermal-influenced zones are 1163, 1391,1433, 790, 1376, and 797 m; moisture-influenced zone are 1361, 1312, 1125, 1028 1148, and 803 m as found in wet summer, monsoon, winter I, winter II, spring, and dry summer respectively. The analysis discovers that bio- and moisture-influenced zones are dependent on meteorological conditions; however, seasonal temperature variations affect the thermal influence zone. In addition, both the Mann–Kendall test and innovative trend analysis have been used to find trends. The importance of SRS data as an alternative for costly and time-consuming in situ datasets has been verified by the present investigation. Consequently, in order to address the problem of environmental degradation, the proposed research will be beneficial in a variety of waste management domains, such as the location of engineered waste disposal facilities and contamination monitoring of different locations adjacent to the dumping sites.

A spatial assessment of temporal forest cover changes is essential for effective forest conservation and management practices. This study analyzes changes in forest cover and the evolution of forest spatial configuration using Landsat satellite imagery over the past three decades (1990–2020) in Azad Jammu and Kashmir (AJK), Pakistan. To achieve the objectives, landscape metrics and forest fragmentation analyses were applied. Additionally, a pattern-based spatial analysis was conducted to examine forest cover changes in the study area. Overall, the forest cover change from 1990 to 2020 was 74 km² (− 1.75%), with an average annual forest cover change rate of − 2.5 km² (− 0.06%) for the entire study period. A gradual decline in forest cover was observed between 1990 and 2020, with the most significant decline of − 29.92 km² from 2000 to 2010. The forest fragmentation analysis reveals that the core forest areas (> 500 acres) are increasingly being divided into smaller (< 250 acres) and medium-sized (250–500 acres) patches. Landscape metrics at the class level show that, with a few exceptions, the overall forests in AJK remain connected and aggregated. Based on forest cover and ecoregions in the region, the pattern-based spatial and dissimilarity analysis identifies forest hotspots (areas of gains or losses) and clusters. To conserve, restore, and monitor the forests in the study area, decision-making and policy-making institutions can establish conservation priorities. They can also implement a more robust incentive-based UN-REDD + mechanism. This would involve formulating management strategies aimed at curbing forest loss and reducing forest degradation.

In recent decades, the use of pesticides has become fundamental to agricultural growth. However, the persistent and toxic nature of pesticides has led to significant concerns regarding their ecological and human health consequences. Therefore, for a better understanding of pesticide contamination and its potential risks, here we assessed the levels of five emerging pesticides—acetochlor, imidacloprid, MCPA, atrazine, and allethrin—in soil samples from ponds used for irrigation and in drinking water samples from nearby areas in Lahore, Pakistan. Our findings revealed that 100% of the samples were contaminated, posing substantial ecological and human health risks. Based on the toxic units (TU_sum), all the soil samples showed higher toxic pressure, exceeding acute and chronic toxicity thresholds for earthworms, while 100% of water samples posed chronic toxicity risks to crustaceans and 10% to algae. Pollution index (PI) analysis further classified 100% of the soil samples and 10% of the water samples as highly polluted. These findings show high-pesticide residues in both soil and water and highlight immediate risk assessment and mitigation measures to protect non-target organisms. This preliminary information can be used to adopt risk assessment monitoring programmes and help higher authorities in making policies and guidelines to mitigate the escalating risk for ecology and humans.

This study uses an environmentally friendly approach to explore a new synthetic pathway for Schiff bases and their metal complexes. A new Schiff base ligand (C) was synthesized by reacting 7-aminodeacetoxycephalosporanic acid with benzaldehyde. The resulting Schiff base was then reacted with three transition metal (Zn, Fe, and Mn) nanoparticles facilitated by ethanolic extracts from three different plant leaves (Moringa oleifera, Azadirachta indica, and Trigonella foenum-graecum) to formulate environmentally friendly nanometal complexes (C1 to C9), which were subsequently evaluated for their anti-bacterial and antioxidant activities. These complexes exhibited crystallite sizes in the range of 7.24-64.24 nm. Structural, compositional, and elemental analysis of the Schiff base ligand and its metal complexes was carried out using FTIR, 1H-NMR, 13C-NMR, XRD, and SEM-EDX, which confirmed the integration of metal moieties within non-uniform sheet-like nanostructures. The thermal properties of all synthesized samples were quantified via TGA, which provides a comprehensive understanding of the thermal properties and decomposition mechanisms of Schiff bases and their metal complexes. Assessment of the antibacterial activity of the Schiff bases and their complexes revealed strong action against both gram-positive (Staphylococcus aureus and Stenotrophomonas maltophilia) and gram-negative (Pseudomonas aeruginosa and Xanthomonas campestris) strains. The prepared samples showed antioxidant activity in the following order: C4 > C5 > C6 > C1 > C2 > C3 > C7 > C8 > C9. Most of the samples, particularly the Zn-complex derived from Moringa, exhibit promising potential for pharmaceutical applications.