Geo-statistical analysis of climatic variability and trend detection in the Hindu Kush region, North Pakistan.

This paper is an effort of geo-statistical analysis of rainfall variability and trend detection in the eastern Hindu Kush region located in the north-west of Pakistan. The eastern section of the HK region lies in the western part of Pakistan. Exploring rainfall variability and quantifying its trend and magnitude is one of the key indicators among all climatic parameters. In the study area, Pakistan Meteorology Department (PMD) has established seven meteorological stations: Drosh, Chitral, Dir, Timergara, Saidu Sharif, Malam Jabba, and Kalam. Daily, mean monthly, and mean annual rainfall time series data for all the met stations were geo-statistically analyzed in the GIS environment for detecting monthly and annual variability in rainfall, variability, and trend detection. Mann-Kendall (MK) and Theil-Sen's slope (TSS) statistical tests were applied to rainfall data. Initially, the MK test was applied for detection of trends and TSS test was used to quantify the change in magnitude. The results indicate that the rainfall variability in intensity and trend pattern detection. The analysis confirms that an extremely significant rainfall trend in the case of mean annual rainfall was predicted at Dir and Malam Jabba meteorological stations. Opposite to this, at Kalam and Chitral stations, a less significant rainfall trend was noted. In a similar context, no prominent rainfall trend has been found at Drosh, Timergara, and Saidu Sharif meteorological stations. Likewise, using TSS, an extremely negative variation in the magnitude of rainfall was verified at Kalam and Malam Jabba. However, a noteworthy positive change in rainfall magnitude has been noted at Dir and Saidu Sharif meteorological stations. The findings of this research have the potential to assist the decision and policy makers and academicians to think truly and conduct more scientific research studies to mitigate climate change.

Estimation of regional meteorological aridity and drought characteristics in Baluchistan province, Pakistan.

Droughts and prevailing arid conditions have a significant impacts on the natural environment, agriculture, and human life. To analyze the regional characteristics of drought in Baluchistan province, the aridity index (AI) and standardized potential evapotranspiration index (SPEI) were used in. The study analyzed the rainfall, temperature, and potential evapotranspiration (PET) data and the same were used for the calculation of AI as well as SPEI to find out the drought spells during the study period. The linear regression and Mann-Kendall test were applied to calculate the trend in AI as well as in SPEI results. The AI results revealed that most of the meteorological stations are arid and semi-arid, where the highest increasing aridity is noted at Kalat (0.0065/year). The results of the SPEI at 1 and 6-months identified the extreme to severe drought spell during 1998-2002 in all meteorological stations of Baluchistan province. The distinct drought spells identified from the SPEI results were in the years 1998-2003, 2006-2010, 2015-2016 and 2019. The drought frequency results showed highest frequency percentage at Lasbella (46%) of extreme to severe drought. The Mann-Kendall trend results showed negative trend in monthly AI and 1-month SPEI results and most significant trend was observed in April and October months, this shows that aridity and drought in the region are decreasing to some extent except Dalbandin and Lasbella observed increasing trend in winter season (November to January months) and Kalat met-station observed increasing trend in June. Prior investigation and planning of drought situations can help in controlling the far-reaching consequences on environment and human society.

Spatial distribution, health risk assessment, and public perception of groundwater in Bahawalnagar, Punjab, Pakistan: a multivariate analysis.

The current study investigated the hydrogeochemical behavior of groundwater quality attributes including arsenic (As) and their associated health risks in unexplored groundwater aquifers of Bahawalnagar, Punjab, Pakistan. The groundwater samples were collected from 40 colonies of Bahawalnagar city from electric/hand pumps, tube wells and turbines installed at varying depth (20 to > 100 m). The groundwater possessed the highest concentrations of PO4 (0.5 mg/L), HCO3 (425 mg/L), Cl (623 mg/L), NO3 (136.68 mg/L) and SO4 (749.7 mg/L) concentrations. There was no difference in concentration of As in shallow and deep aquifers. Interestingly, none of the water samples showed As concentration higher than the WHO limit of 10 µg/L for drinking water with groundwater As concentration spanning from 2.5 to 7.9 µg/L. The HQ values for As were less than 1 and there was no apparent non-carcinogenic risk from the long-term consumption of As contaminated water. The questionnaire survey indicated that 82% respondents believe that drinking water quality affects human health and 55% of respondents considered that groundwater in the area is not suitable for drinking. Survey results revealed that 29.11, 22.78, 17.08, 15.19, 7.59, 5.06 and 3.16% respondents/family members suffered from hepatitis, skin problems, diabetes, tuberculosis, kidney disorders, muscular weakness and gastro, respectively. However, the data cannot be correlated with As contamination and disease burden in the local community and it can be anticipated that the groundwater may contain other potentially toxic ions that are deteriorating the water quality and compromising human health. The hydrogeochemical analysis revealed Na-Cl/SO4, K-SO4 type of groundwater suggesting the potential role of sulfate containing minerals in releasing As in the groundwater aquifers.

Spatio-temporal assessment of land use dynamics and urbanization: linking with environmental aspects and DPSIR framework approach.

Urbanization is the main force of the global environmental as well as land use land cover changes (LULC). Urbanization is caused by prompt increase in population growth, migration, and urge for employment. In this study, Geographic Information System (GIS) was applied for the analysis and representation of spatio-temporal changes in LULC in Peshawar district and these results were linked with environmental aspects and Driver-Pressure-State-Impact-Response (DPSIR) framework approaches. For LULC classification, the Landsat freely available satellite imageries were used. The analysis revealed that the vegetation cover has increased from 37.8% of the total area to 71.3% during 1990-2020 and this change in vegetation is attributed to the government initiatives of Billion Tree Tsunami afforestation project after 2014 which has substantially decreased the barren land (from 66% in 1990 to 19% in 2020) in southeastern part of Peshawar district. Although, there was reduction in the vegetation cover in the past but due to extensive plantation between 2014 and 2020 resulted rapid increase in vegetation cover in the study area. The results of the present study detected a remarkable increase in built-up area which has increased almost 224.6% from 1990 to 2020. The study area population has increased from 2.12 million during 1998 to 4.26 million in 2017. The DPSIR results revealed that drivers and pressure have adverse effects on the carrying capacity of natural resources which have resulted deterioration of ecosystem. The resulted reduced capacity leading towards land degradation, loss of agricultural land, decline the groundwater level and resulted in pluvial flooding in Peshawar district. Government and environmental protection agency should implement the land use bylaws to reduce the rapid and unplanned urban growth and its negative impacts on natural environment.

Spatio-temporal characteristics of meteorological drought in Khyber Pakhtunkhwa, Pakistan.

This study analysed spatio-temporal fluctuations in rainfall to assess drought and wet spells in Khyber Pakhtunkhwa, Pakistan. Temporal changes in rainfall were assessed using a linear regression method, while aridity conditions at each meteorological station were measured using the United Nations Environment Programme climate aridity index. In this study, drought and wet spell patterns were identified using the Standardized Precipitation Evapotranspiration Index (SPEI). The Spearman's Rho (SR) test was applied to find trends in the temporal 1-month and 12-month SPEI data. Balakot, Dir, Kakul, Kalam, Malam Jabba, Parachinar, Patan and Saidu were humid whereas Cherat and Timergara were sub-humid meteorological stations while Bannu, Chitral, Drosh and Peshawar were semi-arid and D.I. Khan was found to be the only arid meteorological station in the study area. The regression results revealed that the amount of rainfall is decreasing at Balakot, Kakul and Dir, while in the southern part of the province the amount of rainfall is increasing, such as in Parachinar and Cherat. The SPEI results revealed distinct drought spells in 1971-1974, 1984-1989, 1998-2004 and recently in 2017-2018, in almost all met-stations results. The SR results indicated a significant wet trend at met-station Parachinar, located in the west, while a significant drying trend has been noted at Balakot in the north-eastern part of the study area. Detailed knowledge about rainfall variability can provide a foundation for the planning and use of water resources.

Bio-monitoring of Tissue Accumulation and Genotoxic Effect of Heavy Metals in Cyprinus carpio from River Kabul Khyber Pakhtunkhwa Pakistan.

The study explored (I) the concentration of heavy metals in water samples (II) their bioaccumulation in common carp Cyprinus carpio (III) and the subsequent genotoxicity in the selected organs of carp; from river Kabul, Khyber Pakhtunkhwa Pakistan. Except for Mercury (Hg) the water samples had all the heavy metals within permissible limits of recommended dietary allowance (RDA). Nonetheless a number of heavy metals (Zn, Ni, Cr, Cd, Pb and Hg) showed bioaccumulation at levels higher than permissible. Zinc (Zn) was the most while Cadmium (Cd) was the least accumulated metal in all tissue samples analyzed. The metal burden in different organs of C. carpio was in sequence of intestine > skin > liver > gills > muscle. The Comet assay established DNA damage in selected organs to be in accordance with metal burden; the most to least damage being in sequence of blood > intestine > skin > liver > gills > muscle. In conclusion assessment of DNA damage in the organs of C. carpio appears to be a useful bio-marker to evaluate genotoxic effects of heavy metal pollution.

The Role of Repeat Head Computed Tomography in The Management of Mild Traumatic Brain Injury Patients with A Positive Initial Head CT

This was a prospective observational study done to evaluate the role of a repeat head CT in patients with mild traumatic brain injury. The aim was to evaluate wether the repeat head CT were useful in providing information that leads to any neurosurgical intervention. 279 adult patients with a mild head injury (GCS 13-15) were enrolled, and these comprised of patients with an initial traumatic intracranial haemorrhage not warranting any surgical intervention. All patients were subjected to a repeat head CT within 48 hours of admission and these showed no change or improvements of the brain lesion in 217 patients (79.2%) and worsening in 62 patients (20.8%). In thirty-one patients, surgical intervention was done following the repeat head CT. All of these patients had a clinical deterioration prior to the repeat head CT. Even if a repeat head CT had not been ordered on these patients, they would have had a repeat head CT due to deteriorating neurological status. When the 62 patients with a worsening repeat head CT were compared with the 217 patients with an improved or unchanged repeat head CT, they were found to have older age, lower GCS on admission, presenting symptoms of headache, higher incidence of multiple traumatic intracranial pathology and lower haemoglobin level on admission. On stepwise multiple logistic regression analysis, three factors were found to independently predict a worse repeat head CT (Table IV). This includes age of 65 years or older, GCS score of less than 15 and multiple traumatic intracranial lesion on initial head CT. As a conclusion, we recommend that, in patients with a MTBI and a normal neurological examination, a repeat cranial CT is not indicated, as it resulted in no change in management or neurosurgical intervention. Close monitoring is warranted in a subset of patients with risk factors for a worsening repeat head CT.