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1.
Animals (Basel) ; 11(3)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806298

RESUMO

Protected areas are a critical tool to conserve biodiversity in the face of the global crisis of species extinction. Here, we present the first ever management effectiveness assessment of Pakistan's Protected Areas (PAs). We link these assessments to the delivery of conservation outcomes focusing on the threatened Western Tragopan (Tragopan melanocephalus) endemic to Pakistan and India. We used two approaches, first mapping the spatial distribution of potential habitat coverage using machine learning ensemble models and second, an assessment of the management effectiveness of protected areas. Our results show that only Machiara National Park scored just above 40% (indicating relatively weak management), 22 of the PAs fell within the 25-50% quantile (indicating weak management), and 3 scored below 25% (indicating poor management). PAs within the species distributional range covered 92,387 ha which is only 2% of the total potential habitat of the Tragopan. Scoring of Planning element was insufficient both in term of the site and species. Likewise, inputs (e.g., research and monitoring program, staff numbers, staff training, current budget, security of budget, and management after process) were also inadequate. Finally, we recommend the establishment of more protected areas within the species potential habitat and inclusion of species-specific plans in Pakistan's PAs management.

2.
R Soc Open Sci ; 7(8): 191957, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32968496

RESUMO

The Upper Indus Basin (UIB) is a major source of supplying water to different areas because of snow and glaciers melt and is also enduring the regional impacts of global climate change. The expected changes in temperature, precipitation and snowmelt could be reasons for further escalation of the problem. Therefore, estimation of hydrological processes is critical for UIB. The objectives of this paper were to estimate the impacts of climate change on water resources and future projection for surface water under different climatic scenarios using soil and water assessment tool (SWAT). The methodology includes: (i) development of SWAT model using land cover, soil and meteorological data; (ii) calibration of the model using daily flow data from 1978 to 1993; (iii) model validation for the time 1994-2003; (iv) bias correction of regional climate model (RCM), and (v) utilization of bias-corrected RCM for future assessment under representative concentration pathways RCP4.5 and RCP8.5 for mid (2041-2070) and late century (2071-2100). The results of the study revealed a strong correlation between simulated and observed flow with R 2 and Nash-Sutcliff efficiency (NSE) equal to 0.85 each for daily flow. For validation, R 2 and NSE were found to be 0.84 and 0.80, respectively. Compared to baseline period (1976-2005), the result of RCM showed an increase in temperature ranging from 2.36°C to 3.50°C and 2.92°C to 5.23°C for RCP4.5 and RCP8.5 respectively, till the end of the twenty-first century. Likewise, the increase in annual average precipitation is 2.4% to 2.5% and 6.0% to 4.6% (mid to late century) under RCP4.5 and RCP8.5, respectively. The model simulation results for RCP4.5 showed increase in flow by 19.24% and 16.78% for mid and late century, respectively. For RCP8.5, the increase in flow is 20.13% and 15.86% during mid and late century, respectively. The model was more sensitive towards available moisture and snowmelt parameters. Thus, SWAT model could be used as effective tool for climate change valuation and for sustainable management of water resources in future.

3.
Animals (Basel) ; 10(10)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987899

RESUMO

Gadani shipbreaking area, located on the coastline of Pakistan, is an important fish production area. In this study, levels of four metals (Ni, Pb, Cd, and Mn) in 148 muscle and gill samples of seven fish species (Small-scale terapon, Torpedo scade, Sicklefish, Saddle grunt, Gold silk seabream, Indian mackerel, Spotted sickle fish) and seawater samples, taken from 9 sampling sites in the shipbreaking area, were determined. In addition, multiple approaches were used to assess human health risks from fish consumption. Trace metal concentration in seawater ranged from 0.05 to 1.96 mg/L in shipbreaking vicinity and 0.03 to 0.97 mg/L in the reference site (Miani Hor). However, metal accumulations in fish species ranged from 1.33 to 5.26 µg/g. Among trace metals, the level of Pb in all fish species was highest, followed by Ni, Mn, and Cd. The bioaccumulation factors (BAFs) for both gills and muscles displayed the order: Mn > Cd > Ni > Pb. Estimated daily intake (EDI) values were below the tolerable daily intake (TDI). Based on target hazard quotient (THQ), the investigated fish species were safe regarding Pb and Mn (THQ < 1), while they may cause potential risk regarding Cd and Ni (THQ > 1). After comparison with maximum permissible limits, heavy metal concentration in the edible muscle tissues of all the analyzed fish species from the Gadani coast were found safe for human consumption.

4.
J Environ Sci (China) ; 22(12): 1854-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21462701

RESUMO

Groundwater contamination due to pesticide applications on agricultural lands is of great environmental concern. The mathematical models help to understand the mechanism of pesticide leaching in soils towards groundwater. We developed a user-friendly model called ArcPRZM-3 by integrating widely used Pesticide Root Zone Model version 3 (PRZM-3) using Visual Basic and Geographic Information System (GIS) based Avenue programming. ArcPRZM-3 could be used to simulate pesticide leaching towards groundwater with user-friendly input interfaces coupled with databases of crops, soils and pesticides. The outputs from ArcPRZM-3 could be visualized in user-friendly formats of tables, charts and maps. In this study we evaluated ArcPRZM-3 model by simulating bentazon leaching in soil towards groundwater. ArcPRZM-3 was applied to 37 sites in Woodruff County, Arkansas, USA to observe the daily average dissolved bentazon concentration for soybean, sorghum and rice at a depth of 1.8 m for a period of two years. Nineteen ranks of bentazon leaching potential were obtained using ArcPRZM-3 for all sites having different soil and crop combinations. ArcPRZM-3 simulation results for bentazon were compatible with the field monitored data in term of relative ranking and trend, although some uncertainties exist. This study indicated that macropore flow mechanism would be important in analyzing the effect of irrigation on groundwater contamination due to pesticides. Overall, ArcPRZM-3 could be used to simulate pesticide leaching towards groundwater more efficiently and effectively as compared to PRZM-3.


Assuntos
Benzotiadiazinas/análise , Herbicidas/análise , Modelos Químicos , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análise , Arkansas , Monitoramento Ambiental , Sistemas de Informação Geográfica , Chuva
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