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Urbanization in Pakistan is increasing at 3% annually, the highest in South Asia. 50% of the population is expected to urbanize by 2025. The capital city of Pakistan, Islamabad has experienced phenomenal increase in the urban population and extent in the last four decades. The aim of this research was to analyze the urban sprawl of Islamabad and changes in the Land Use and Land Cover (LULC), with the help of satellite images. LULC statics were extracted from Landsat Multi-Spectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+) and Operational Land Imager (OLI) images, for the years 1979, 1989, 1999, 2008 and 2019. There is an increase of 377 sq. km in built-up areas and slight increase of 47 sq km in the agriculture land. The forest cover has been reduced by 83 sq km and the water bodies have also reduced. The barren land has experienced an unprecedented decrease of 333 sq km in the meanwhile. The master plan is under revision to regularize such uncontrolled constructions and accommodate the increased demand. The city, as a result, has been facing issues of water supply, sanitation, transportation etc. This has seriously jeopardized the master plan of the city.

The unchecked and unplanned expansion of urban areas has led to the conversion of millions of green areas to gray areas. The recent urban growth patterns of Pakistan’s metropolitan twin cities, Islamabad and Rawalpindi, is a matter of concern for the surrounding green areas. The present study aimed to categorize and quantify the land-use and land-cover change (LULCC) patterns and the corresponding impacts on the forest carbon dynamics around Islamabad and Rawalpindi. Multispectral satellite images for the year 1990 (Landsat 5 TM) and 2020 (Landsat 8 OLI) were used to determine, quantify, and compare the LULCC inside and around the twin metropolitan cities. Field inventory surveys in the reserved forests of Rawalpindi and Islamabad were also conducted to determine the amount of stored carbon in these forests. Our results showed an accelerated annual urban expansion (i.e., an increase in the built-up area) of 16.49% and 26.72% in Rawalpindi and Islamabad, respectively, during the study period. Similarly, the amount of barren land and agricultural land was reduced at an annual rate of 2.08% and 2.18%, respectively, in Rawalpindi and 0.25% and 1.04% in Islamabad. A reduction in the area of barren mountains also occurred at an annual of 2.26% in Islamabad, while it increased by 4.16% in Rawalpindi. The amount of carbon stored in the reserved forests of Islamabad stood at 139.17 ± 12.15 Mg C/ha while that of Rawalpindi was 110.4 ± 13.79 Mg C/ha. In addition, total stored forest carbon was found to have decreased from 544.70 Gg C to 218.05 Gg C in Rawalpindi, while in Islamabad it increased from 2779.64 Gg C to 3548.16 Gg C. Investment in ecological urban planning, sustainable cities, and appropriate land-use planning is recommended to curb the degradation and conversion of the surrounding green areas of Rawalpindi and Islamabad.

A comprehensive life cycle assessment (LCA) was conducted for the matchsticks industry in the Khyber Pakhtunkhwa province of Pakistan to quantify environmental footprint, water footprint, cumulative energy use, and to identify improvement opportunities in the matchsticks manufacturing process. One carton of matchsticks was used as reference unit for this study. Foreground data was collected from the matchsticks industry through questionnaire surveys, personal meetings, and field measurements. The collected data was transformed into potential environmental impacts through the Centre for Environment Studies (CML) 2000 v.2.05 method present by default in the SimaPro v.9.1 software. Water footprint was calculated using methodology developed by Hoekstra et al., 2012 (water scarcity index) V1.02 and cumulative energy demand by SimaPro v.9.1 software. The results showed that transport of primary material (wood logs), sawn wood for matchsticks, red phosphorous, acrylic varnish, and kerosene fuel oil contributed to the overall environmental impacts. Transport of primary materials and sawn timber for matchsticks contributed significantly to abiotic depletion, global warming, eutrophication potential, ozone depletion, corrosion, human toxicity, and aquatic ecotoxicity effects. The total water footprint for manufacturing one carton of matchsticks was 0.265332 m3, whereas the total cumulative energy demand was 715.860 Mega Joules (MJ), mainly sourced from non-renewable fossil fuels (708.979 MJ). Scenario analysis was also conducted for 20% and 30% reduction in the primary material distance covered by trucks and revealed that reducing direct material transport distances could diminish environmental impacts and energy consumption. Therefore, environmental footprint could be minimized through diverting matchsticks industries freight from indigenous routes to high mobility highways and by promoting industrial forestry close to industrial zones in Pakistan. Many industries did not have emissions control systems, exceeding the permissible limit for emissions established by the National Environmental Quality Standards (NEQS) of Pakistan. Thus, installation of emissions control system could also diminish emissions from match industry in Pakistan.

Water-use efficiency (WUE) at the whole-plant level plays as an important role as an indicator of both the water-use strategy of the plant, and the ecophysiological processes linking the carbon and water cycles. However, the variation in the annual pattern of WUE, the interannual trends, and the regulating factors of WUE in rubber plantations remain poorly understood. Here, we used a four-year (2013–2016) continuous biometric survey along with sap flow data recorded at a monthly resolution to examine the annual and interannual dynamics of WUE and the relationships of WUE with environmental and biological factors in rubber (Hevea brasiliensis) plantations in Southwest China. The results showed that (1) there was no definitive pattern in WUE between April and December, but the peak WUE values generally occurred around August; (2) the multi-year mean WUE was 2.34 ± 0.19 g C·kg−1 H2O, and a negative correlation of WUE to photosynthetically active radiation was found at the interannual scale (r = −0.962, P

The study of Land Use Land Cover (LULC) changes and their patterns enhance our understanding about various man caused phenomenon on earth surface. The Capital City of Pakistan, Islamabad has expereinced high rate of urbanization and population increase in the last 3-4 decades and as a result, the LULC changes have occurred in an unsustainable way. The accurate and reliable data of LULC changes for the study period is not available. The main aim of this study was to provide compatible data on LULC change during the last 40 years for the functional city Islamabad, Pakistan. LULC statistics were extracted from Landsat Multi-Spectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+) and Operational Land Imager (OLI) images. For each of the target years (1979, 1989, 1999, 2009 and 2019) LULC information was obtained through a supervised classification algorithm. The study area was classified into five major landscape categories, namely built-up, agriculture, forest, water bodies and barren land. The results have indicated that the urban expansion has been increasing due to mass migration and uncontrolled urbanization in the city. The urban sprawl analysis revealed that built-up area and agricultural land has expanded by 41.7% and 5.20% respectively, during 1979–2019. On the other hand, the forest and water bodies declined by 9.03% and 1.21% respectively. The land use changes, have forced the planners to revise the original master plan of the city and including the agricultural sector in the housing area during 2019.

This study focused on phytoremediation of chromium (Cr) through endophytic bacteria. Four endophytic bacteria i.e. Pseudomonas putida (CEN2), Pseudomonas aeruginosa (CEN3), Acinetobacter baumanni (CEN4), and Pseudomonas aeruginosa (CEN5) were selected for phytoremediation experiments to investigate its effects on plant growth and Cr uptake. Phytoremediation experiment was carried out by using one hyper accumulator (Brassica napus) and one non-hyper accumulator plant (Coriandrum sativum), grown in agricultural soil amended with three different concentrations 50 ppm, 100 ppm and 200 ppm of Cr for 60 days. In Brassica napus, endophytic consortia showed maximum root, shoot elongation and vigour index at all concentrations. In Coriandrum sativum CEN5 strain showed maximum root, shoot length and vigour index. Brassica napus with consortia produced maximum fresh and dry biomass as compared to the control treatments. Therefore, endophytic-assisted phytoremediation could be a promising tool for mitigating heavy metals toxicity from polluted soil without any negative effects on plant growth.

Changes in land use cover, particularly from forest to agriculture, is a major contributing factor in increasing carbon dioxide (CO2) level in the atmosphere. Using satellite images of 1999 and 2011, land use and land use changes in the Kumrat valley KPK, Pakistan, were determined: a net decrease of 11.56 and 7.46 % occurred in forest and rangeland, while 100 % increase occurred in agriculture land (AL). Biomass in different land uses, forest land (FL), AL, and range land (RL) was determined by field inventory. From the biomass data, the amount of carbon was calculated, considering 50 % of the biomass as carbon. Soil carbon was also determined to a depth of 0–15 and 16–30 cm. The average carbon stocks (C stocks) in all land uses ranged from 28.62 ± 13.8 t ha−1 in AL to 486.6 ± 32.4 t ha−1 in pure Cedrus deodara forest. The results of the study confirmed that forest soil and vegetation stored the maximum amount of carbon followed by RL. Conversion of FL and RL to AL not only leads to total loss of about 56 % (from FL conversion) and 37 % (RL conversion) of soil carbon in the last decades but also the loss of a valuable carbon sink. In order to meet the emissions reduction obligations of the Kyoto Protocol, Conservation of forest and RL in the mountainous regions of the Hindu Kush will help Pakistan to meet its emissions reduction goals under the Kyoto Protocol.

Biomass is the component of living organism and mostly obtained from plants, animals, insects and the residue of all the mentioned organisms. Biomass is the key source of energy present in the form of organic matter. The study aimed to find out biomass and its variation in each component of Betula utilis D. Don (Birch Tree) with varying diameter at Kalam forest division Swat, Khyber Pakhtunkhwa (KPK) province, Pakistan. The biomass of different components was determined by non-destructive methods. Overall, 30 trees were selected from different diameter classes viz a viz up to 10, 11 - 20 and greater than 20 cm. Ten trees were selected from each class. The diameter of stem and large branches and their length were measured in the field. Later, the volumes of stem and branches were calculated and converted into biomass. The study revealed that stem contributes 42.65% biomass followed by large and sub branches as 39.22% and 13.54% respectively. Leaves contribute 4.59% only. The above tree biomass contribution by different components was arranged as stem was greater than large branches; these were greater than sub branches and the lowest was in leaves. The total above ground biomass of single tree was 20.59, 58.041 and 197.214 kg·tree-1 respectively for diameter up to 10, 11 - 20 and greater than 20 cm. The averaged biomass in all diameter classes was 91.95 ± 93.064 kg·tree-1. The total biomass of single tree of diameter class up to 10, 11 - 20 and greater than 20 cm was 24.71, 69.649 and 236 kg respectively. The below ground biomass of single tree of diameter class up to 10, 11 - 20 and greater than 20 cm was 4.11 ± 1.24 kg, 11.61 ± 3.56 kg and 39.44 ± 8.9 kg respectively. The biomass expansion factor was 1.34, 1.47, and 1.5 t·m-3 respectively for diameter classes up to 10 cm, 11 - 20 cm and greater than 20 cm respectively. The mean biomass expansion factor for all diameter classes was 1.44 t·m-3.

Mountain environments in the world host highly specialized flora and fauna which are vulnerable because of land use and climate change. Transhumance and other land use traditional practices are present in most of the mountains of the world, and management tools able to cope with new socioeconomic settings and environmental changes are urgently needed. During past centuries, yak (Bos grunniens) herding in Northern Pakistan involved the migration of herds to high mountain international rangelands, but the recent establishment of international borders breaks the traditional transhumance paths, promoting several ecological problems. In this paper, we propose the use of least cost path (LCP) algorithm to identify the most efficient corridors of transhumance for yak herds on northern high altitudes of Pakistan. Specifically, LCP was implemented to identify the critical grazing areas and the connecting zones to be accounted in a new management plan for the yaks in the region. The LCP analysis showed that some grazing areas are connected with several paths, whereas other areas are connected to a lesser extent. The analyses identified a set of best minimum cost paths able to guarantee local connectivity. We also delineated several medium and low efficient paths that could play a crucial role for maintaining regional connectivity which is essential for reducing the isolation of herds and the consequent inbreeding problems. The analytical framework implemented in this study allowed to (1) provide valuable information concerning the movement of yak herds in Gilgit-Baltistan, (2) identify potential corridors that are able to promote herd movement between villages and high mountain rangelands, and (3) identify critical areas for the connectivity of yaks by ranking of the potential corridors according to their length and permeability. The analysis would be extended to other transhumant herds and high mountain areas that are facing sociopolitical transformations and environmental changes.

Very old natural forests comprising the species of Fagaceae (Lithocarpus xylocarpus, Castanopsis wattii, Lithocarpus hancei) have been prevailing since years in the Ailaoshan Mountain Nature Reserve (AMNR) SW China. Within these forest trees, density is quite variable. We studied the forest structure, stand dynamics and carbon density at two different sites to know the main factors which drives carbon sequestration process in old forests by considering the following questions: How much is the carbon density in these forest trees of different DBH (diameter at breast height)? How much carbon potential possessed by dominant species of these forests? How vegetation carbon is distributed in these forests? Which species shows high carbon sequestration? What are the physiochemical properties of soil in these forests? Five-year (2005–2010) tree growth data from permanently established plots in the AMNR was analysed for species composition, density, stem diameter (DBH), height and carbon (C) density both in aboveground and belowground vegetation biomass. Our study indicated that among two comparative sites, overall 54 species of 16 different families were present. The stem density, height, C density and soil properties varied significantly with time among the sites showing uneven distribution across the forests. Among the dominant species, L. xylocarpus represents 30% of the total carbon on site 1 while C. wattii represents 50% of the total carbon on site 2. The average C density ranged from 176.35 to 243.97 t C ha−1. The study emphasized that there is generous degree to expand the carbon stocking in this AMNR through scientific management gearing towards conservation of old trees and planting of potentially high carbon sequestering species on good site quality areas.

The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions, including those related to forests. This paper describes the status of carbon stocks in sub tropical forests of Pakistan. There are two major sub types in subtropical forests of Pakistan viz a viz Subtropical Chir Pine and Subtropical broadleaved forests. A network of sample plots was laid out in four selected site. Two sites were selected from sub tropical Chir Pine (Pinus roxburghii) forests and two from Subtropical broadleaved forests. Measurement and data acquisition protocols were developed specifically for the inventory carried out from 2005 to 2010. In total 261 plots (each of 1ha.) were established. Estimation of diameter, basal area, height, volume and biomass was carried out to estimate carbon stocks in each of the four carbon pools of above- and below-ground live biomass. Soil carbon stocks were also determined by doing soil sampling. In mature (∼100 years old) pine forest stand at Ghoragali and Lehterar sites, a mean basal area of 30.38 and 26.11 m2·ha−1 represented mean volume of 243 and 197 m3·ha−1, respectively. The average biomass (t·ha−1) was 237 in Ghoragali site and 186 t·ha−1in Lehterar site, which is equal to 128 and 100 t C ha−1 including soil C. However, on average basis both the forests have 114.5± 2.26 t·ha−1 of carbon stock which comprises of 92% in tree biomass and only 8% in the top soils. In mixed broadleaved evergreen forests a mean basal area (m2·ha−1) was 3.06 at Kherimurat with stem volume of 12.86 and 2.65 at Sohawa with stem volume of 11.40 m3·ha−1. The average upper and under storey biomass (t·ha−1) was 50.93 in Kherimurat site and 40.43 t·ha−1in Sohawa site, which is equal to 31.18 and 24.36 t C ha−1 including soil C stocks. This study provides a protocol and valuable baseline data for monitoring biomass and carbon stocks in Pakistan’s managed and unmanaged sub-tropical forests.