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Forest cover change assessment in conflict-affected areas of northwest Pakistan: the case of swat and shangla districts 总被引：2，自引：2，他引：0
Faisal Mueen QAMER Sawaid ABBAS Rashid SALEEM Khurram SHEHZAD Hassan ALI Hammad GILANI 《山地科学学报》2012,9(3):297-306
This study examines the spatial and temporal forest cover changes in Swat and Shangla districts to understand the deforestation pattern in context of the recent security conflict in these districts. We used multi-resolution satellite images to assess the long term deforestation from 2001 to 2009 and also to identify episodic forest cutting areas appeared during the conflict period of Oct. 2007 - Oct. 2008. There are only 58 ha of deforestation identified during the conflict period while 1268 ha of gross annual deforestation were assessed during last eight years. Most of the deforestation patches persist around the administrative boundaries at sub-district levels (tehsils) which can be attributed to ambiguity in unclear jurisdiction between the forest official. The results highlight that the forest cutting appeared in Swat and Shangla during the conflict period is not as significant when compared with the long term deforestation pattern in the area. On the one side the results of the study are supportive to the picture that emerges from international studies which report high rate of deforestation in the country and on the other side it negates any relation between the security situation and the increasing deforestation in the north western Pakistan. The study concludes that deforestation assessments require verification by independent sources of data, such as satellite imagery to improve our understanding of deforestation processes. 相似文献
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利用瞬变电磁（TEM）和地面电磁（GEM）方法,本文研究了埃及Hawara遗址区的地下水对遗址的影响.这个遗址包括Hawara金字塔、北区墓地、以及被称作“迷宫”的南区墓葬场所.现今Hawara遗址已经完全荒废,被耕作区和Bahr Wahba运河包围.地表水和地下水会破坏Hawara金字塔和“迷宫”遗址的地基,现在金字塔入口已被淹没至地面下约6 m深处.本文在耕作区、金字塔以及“迷宫”等三个地区进行了TEM勘察;在“迷宫”地区进行了GEM勘察.综合分析以上两种勘察数据,我们发现,农业灌溉是浸入到地下的水的主要来源;本地区地下水位随着观测点及海拔的不同,在地面以下2~7 m之间变化. 相似文献
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In this paper, analytical methods, artificial neural network (ANN) and multivariate adaptive regression splines (MARS) techniques were utilised to estimate the discharge capacity of compound open channels (COC). To this end, related datasets were collected from literature. The results showed that the divided channel method with a coefficient of determination (R 2) value of 0.76 and root mean square error (RMSE) value of 0.162 has the best performance, among the various analytical methods tested. The performance of applied soft computing models with R 2=0.97 and RMSE = 0.03 was found to be more accurate than analytical approaches. Comparison of MARS with the ANN model, in terms of developed discrepancy ratio (DDR) index, showed that the accuracy of MARS model was better than that of MLP model. Reviewing the structure of the derived MARS model showed that the longitudinal slope of the channel (S), relative flow depth (H r ) and relative area (A r ) have a high impact on modelling and forecasting the discharge capacity of COCs. 相似文献
4.
1 INTRODUCTION Pelteobagrus fulvidraco (Richardson, 1846) or yellow catfish is slender and scaleless with a gently sloping dorsal profile from anterior to posterior. It is generally black-brown to black-yellow on the back, light yellow on the belly, with … 相似文献
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Deforestation Trends and Spatial Modelling of its Drivers in the Dry Temperate Forests of Northern Pakistan–A Case Study of Chitral 总被引：2，自引：2，他引：0
Khuram Shehzad Faisal M. Qamer M. S. R. Murthy Sawaid Abbas Laxmi D. Bhatta 《山地科学学报》2014,11(5):1192-1207
Deforestation is a major environmental challenge in the mountain areas of Pakistan. The study assessed trends in the forest cover in Chitral tehsil over the last two decades using supervised land cover classification of Landsat TM satellite images from 1992, 2000, and 2009, with a maximum likelihood algorithm. In 2009, the forest cover was 10.3% of the land area of Chitral(60,000 ha). The deforestation rate increased from 0.14% per annum in 1992–2000 to 0.54% per annum in 2000–2009, with 3,759 ha forest lost over the 17 years. The spatial drivers of deforestation were investigated using a cellular automaton modelling technique to project future forest conditions. Accessibility(elevation, slope), population density, distance to settlements, and distance to administrative boundary were strongly associated with neighbourhood deforestation. A model projection showed a further loss of 23% of existing forest in Chitral tehsil by 2030, and degradation of 8%, if deforestation continues at the present rate. Arandu Union Council, with 2212 households, will lose 85% of its forest. Local communities have limited income resources and high poverty and are heavily dependent on non-timber forest products for their livelihoods. Continued deforestation will further worsen their livelihood conditions, thus improved conservation efforts are essential. 相似文献
7.
ASHRAF Sobia ABBAS Farhat IBRAHIM Muhammad RASHID Umer KHALID Shoaib Raza AHMAD Hammad Rehman HAKEEM Khalid MAJEED Tahir 《地理学报(英文版)》2015,25(2):225-235
Groundwater is the most appropriate and widely used source of drinking water, which is increasingly threatened by pollution from industrial and agricultural activities. To check the severity of the problem, 156 groundwater samples were collected from various depths (60-110 ft) of 52 different localities in Faisalabad city, the third largest metropolis in Pakistan, and analyzed for the metals (Zn, Cu, Cd, Ni, Pb, Mn and Fe) concentration in 2009. Quantification was done by using Flame Atomic Absorption Spectrophotometer technique and the results were compared with WHO standards for drinking water quality. Results showed that the levels of Cu, Mn and Fe were below the WHO standards while the concentrations of Zn, Cd, Ni and Pb were above the recommended levels of safe drinking water. Correlation analysis among the occurrence of these heavy metals revealed a highly significant and positive correlation of Mn with Zn and Fe. A significant and positive correlation of Cd was also found with Cu and groundwater depth showing that there is strong association between Cu-Cd pair and that the Cd concentration varies with depth of groundwater in the study area. Regional patterns of heavy metals occurrence were mapped using Geographical Information System (GIS) for the identification and demarcation of risk areas. The concentration maps may be used by policymakers of the city to mitigate groundwater pollution. 相似文献
8.
The Lower Carboniferous sediments at Wadi Abu El Mogheirat consist of four stratigraphic formations, from base upwards: Um Bogma, El Hashash, Magharet El Maiah and Abu Zarab formations. The most-concentrated radioactive anomalies at Wadi Abu El Mogheirat are in the middle member of the Um Bogma Formation. The gibbsitic marl in this formation shows the highest uranium contents (around 710 ppm). Gibbsitic marl and black gibbsite of the middle Um Bogma Formation show higher enrichment in Co, Cu, Mn, Ni, Pb, Zn, U, V, Ce and Th. Black gibbsite contains the highest total rare earth elements concentration, especially in terms of LREEs, while gibbsitic marl contains the highest content of HREEs. Anomalous contents of gold at Wadi Abu El Mogheirat are recorded for the first time in the gibbsitic marl (content: 10.4 ppm), black gibbsite (2.8 ppm) of the middle member of the Um Bogma Formation and in the siltstones of the El Hashash Formation (0.6 ppm). Gibbsitic marl shows the presence of uranothorite, celestite, zircon, atacamite, barite, xenotime and rutile. These characteristic demonstrate that the middle member of the Um Bogma Formation constitutes a potential source for gold. This conclusion is reinforced by the potential to exploit other metals such as Co, Cu, Mn, Ni, Pb, Zn, U, V, Th and Ce as by-products. 相似文献
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Paleozoic rocks in the Wadi El Sahu area are affected by many major faults in different directions. A reverse fault trending NE-SW is exposed for about 300 m of its length as it cuts through the Abu Hamata and Adedia formations on the south side of Wadi El Sahu. A secondary ascending hydrothermal solution carrying heavy metals and radioactive minerals passed through the fault plain and the surrounding fractures, forming mineralized and radioactive zone. The mineralized zone thickness ranges from 60 cm to 200 cm along the fault plain. These rocks were analyzed radiometrically using a portable gamma-ray spectrometer, chemically by employing ICP-ES and ICP-MS, as well as mineralogically by both binocular and Environmental Scanning Electron microscope. Gold content was also determined by fire assay. REE and U contents reached up to 2682 and 1216 ppm, respectively. Mineralogical investigations indicated the presence of uraninite, torbernite, autunite, sklodowskite, kasolite as uranium minerals, thorite as a thorium mineral, monazite, allanite and xenotime as REE-bearing minerals, zircon and columbite as accessory minerals, gold and nickel as precious and base metals, in addition to cassiterite, chalcopyrite, chalcocite and chrysocolla. High REE and U contents are attributed to the circulation of epigenetic U and REE-bearing hydrothermal solutions along the fault plain and its surrounding fractures. Hydrothermal alteration processes could then be confirmed by the presence of the M-type tetrad effect in the REE-patterns of the ferruginous sandstone. The non-chondritic ratio of Nb/Ta, Zr/Hf and Y/Ho in the studied sandstone may be attributed to the tetrad effect. The Ce and Eu anomaly with unusual REE-patterns was represented by the presence of conjugated M-W tetrad effects, indicating either the dual effect of hydrothermal solutions or groundwater with seawater. The results clarify that the tetrad-effects could be used as evidence for the environment of deposition and as an indication for gold mineralization. 相似文献
10.
Sobia Ashraf Farhat Abbas Muhammad Ibrahim Umer Rashid Shoaib Khalid Hammad Raza Ahmad Khalid Rehman Hakeem Tahir Majeed 《地理学报(英文版)》2015,(2):225-235
Groundwater is the most appropriate and widely used source of drinking water,which is increasingly threatened by pollution from industrial and agricultural activities.To check the severity of the problem,156 groundwater samples were collected from various depths(60-110 ft) of 52 different localities in Faisalabad city,the third largest metropolis in Pakistan,and analyzed for the metals(Zn,Cu,Cd,Ni,Pb,Mn and Fe) concentration in 2009.Quantification was done by using Flame Atomic Absorption Spectrophotometer technique and the results were compared with WHO standards for drinking water quality.Results showed that the levels of Cu,Mn and Fe were below the WHO standards while the concentrations of Zn,Cd,Ni and Pb were above the recommended levels of safe drinking water.Correlation analysis among the occurrence of these heavy metals revealed a highly significant and positive correlation of Mn with Zn and Fe.A significant and positive correlation of Cd was also found with Cu and groundwater depth showing that there is strong association between Cu-Cd pair and that the Cd concentration varies with depth of groundwater in the study area.Regional patterns of heavy metals occurrence were mapped using Geographical Information System(GIS) for the identification and demarcation of risk areas.The concentration maps may be used by policymakers of the city to mitigate groundwater pollution. 相似文献