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Range extension of four highland agamid lizards in Shimshal Pamir,pakistan

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Journal of Arid Land 2012年第1期4卷 77-84页

作者： Babar KHAN Waseem AHMED Abdukadir Ablimit Shamim FAKHRI Hassan ALI pakistan Wildlife Foundation Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences world wide fund for nature pakistan Zoological Survey Department

As part of the Sino-Pak trans-boundary cooperation for conservation and sustainable development in Pamir border region, world Wild fund （WWF）-pakistan conducted a preliminary social, economic and ecological survey in the ShimshaI-Pamir Lakes area in July 2009. The purpose of the study was to explore potentials and opportunities for future collaborative conservation of some species, habitats and high altitude ecosystems in the border region between China and pakistan. The two-week herpetological study in the Shimshal Pamir area of Khunjerab National Park （KNP） along pakistan-China border was an integral part of the survey, conducted exclu- sively to document reptilian fauna with a special emphasis on investigating their occurrence, distribution and status in the study area. Field investigations were performed during daytime when it was hot enough and reptiles were active, basking or feeding. A total of 15 specimens belonging to four species of the Agamidae family were captured by striking stones and beating bushes with sticks. Collected specimens were preserved using 10% formalin solution, tagged with field information and stored in Zoological Survey Department, Karachi for future reference. Laboratory investigations were carried out for pholidosic counts and morphometric measurements. A detailed review of relevant literature, habitat characteristics and laboratory investigations revealed the occurrence of Laudakia himalayana, L. pakistanica, L. tuberculata and L. badakhshana at 4,082 m, 4,172 m, 4,005 m and 4,240 m asl, respectively, which are much higher altitudes as compared to the previously reported heights of 3,353 m, 3,200 m, 2,500 m and 2,400 m asl. The terrain offers a variety of ecological barriers, in the form of fast and freezing running waters and massive glaciers with peculiar harsh climatic conditions prevailing for nine months of the year, which restricts species migration and thus increases endemism. Although one of the four species recorded from the

关键词： Laudakia himalayana L. pakistanica L. tuberculat L. badakhshana Agarnidae Gilgit-Baltistan Khunjerab National Park pakistan

Forest Cover Change Assessment in Conflict-affected Areas of Northwest pakistan: the Case of Swat and Shangla Districts

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Journal of Mountain Science 2012年第3期9卷 297-306页

作者： Faisal Mueen QAMER Sawaid ABBAS Rashid SALEEM Khurram SHEHZAD Hassan ALI Hammad GILANI world wide fund for nature(WWF)pakistan LahorePakistan International Centre for Integrated Mountain Development(ICIMOD) KathmanduNepal Asian Institute of Technology BangkokThailand

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.

关键词： Forest cover change Deforestation Conflict-affected area GIS pakistan

The effects of prey depletion on dietary niches of sympatric apex predators in Southeast Asia

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Integrative Zoology 2021年第1期16卷 19-32页

作者： Robert STEINMETZ Naret SEUATURIEN Pairoj INTANAJITJUY Pichet INRUEANG Kittipat PREMPREE world wide fund for nature-Thailand BangkokThailand and 2 Kuiburi National ParkPrachuapkirikhanThailand

Resource depletion exerts opposing pressures on co-occurring consumers to expand diets while limiting overlap with *** foraging theory as a framework,we tested the effects of prey availability on diet spe-cialization and overlap among competing Asian predators:dhole,leopard,and *** used scat analysis from a prey-poor site,combined with a quantitative synthesis of 40 other diet studies,to determine biomass of different prey types consumed by each *** then assessed diet composition in relation to prey density,and compared diet breadth and overlap between prey-poor and prey-rich *** prey rich areas,all three predators specialized on energetically profitable medium and large ungulates(>30 kg),resulting in narrow,overlapping *** predator shifted toward less profitable small-bodied prey(≤30 kg)as preferred ungulates declined,whereas con-sumption of preferred ungulates was unrelated to small prey abundance,as predicted by foraging *** breadths doubled under prey depletion(except leopard),but overlap declined as diets diverged via species-specific traits that facilitated capture of different types of alternative ***’s apex predators adapt similarly to depletion of mutually preferred ungulates by switching to more numerous but less profitable small *** they can also partition a depleted prey base through intrinsic niche differences,thereby avoiding competitive *** find-ings illuminate the stabilizing properties of adaptive foraging and niche differences in ecological communities,and provide insights into the behavior and resilience of Asia’s endangered apex predators in response to prey depletion in the heavily poached forests of this region.

关键词： coexistence dhole leopard niche overlap optimal foraging theory

Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture

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Acta Geochimica 2024年第2期43卷 214-234页

作者： Maria Kaleem Erum Bashir Shahid Naseem Tahir Rafique Bushra Shahab Department of Geology University of KarachiKarachi 75270Pakistan Applied Chemistry Research Centre PCSIR Laboratories ComplexKarachi 75280Pakistan

This study is theﬁrst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical *** outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the ***-ﬁve soil samples were collected,mainly from the arable land of the Porali *** drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric ***-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial *** granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt *** indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of *** indices reﬂect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr *** of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the *** correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type *** may result in the undesirable accumulation of certain trace elements which adversely affects crops.

关键词： Weathering indices Pollution indices Accumulation Repercussions Trace elements Multivariate analyses Porali Plain Balochistan

Variable range hopping transport and dielectric relaxation mechanism in GdCrO_(3) rare-earth orthochromite perovskite

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Journal of Rare Earths 2024年第7期42卷 1304-1316,I0004页

作者： Muhammad Javed Ayaz Arif Khan Jamal Kazmi Naeem Akbar Said Nasir Khisro Amanullah Dar Aleem Dad Khan Tareen Mohd Ambri Mohamed Department of Physics The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Physics University of Kotli Azad Jammu and KashmirKotli11100Pakistan Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia Department of Mathematics University of Kotli Azad Jammu and KashmirKotli11100Pakistan

The polycrystalline GdCrO_(3)(GCO)perovskite orthochromite was synthesized by the sol-gel auto-combustion *** Rietveld refined X-ray diffraction(XRD)profile of GCO confirms that the orthorhombic phase crystallizes in perovskite crystal structure with space group *** transmission electron microscopy and selected area electron diffraction divulge the polycrystalline nature of the perovskite *** field emission scanning electron microscopy(FESEM)images reveal the microstructural polyhedral growth of grains separated by sharp grain *** chemical states of the ions present in the compound were investigated by X-ray photoelectron spectroscopy(XPS)studies,and the electrical pathways were *** impedance studies were carried out in the experimental frequency and temperature ranges of 40 Hz-4 MHz and 178-408 K,*** equivalent circuit model(RGQG)(RGBQGB)resolves the impedance response into two contributions originating from the intra-grain and inter-granular micro-constituents of the *** electrical conduction mechanism is based on the Mott variable range hopping *** complex electric modulus studies demonstrate the short-and long-range mobility of the charge carriers and rule out the presence of electrode effects on the dielectric relaxation mechanism of the *** decreasing pattern of dielectric permittivity with frequency is explained by the Maxwell-Wagner type of *** frequency dependence of the loss factor exhibits the presence of thermally activated relaxation time distribution in the material.

关键词： Auto-combustion Perovskite Electro-ceramic Dielectric Electrical transport Impedance

Robinia pseudoacacia leaves improve soil physical and chemical properties

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Journal of Arid Land 2010年第4期2卷 266-271页

作者： Babar KHAN Abdukadir Ablimit Rashed MAHMOOD Muhammad QASIM world wide fund for nature Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences COMSATS Institute of Information Technology

The role of the leaves of Robinia pseudoacacia L., which is widely distributed in the arid lands, on improving soil physical and chemical properties was analyzed at various incubation periods. The incubated soils added with 0, 25, 50 and 75 g Robinia pseudoacacia leaves were tested after consecutive incubation intervals of 6, 8 and 10 months and the different soil parameters were measured. The results showed the increases in organic matter (OM), extractable K, cation exchange capacity (CEC), aggregate stability and water holding capacity, but the decreases in pH value and bulk density after 6 months’ incubation. The gradual decrease in change rates of soil properties indicated less microbial population and organic residual mineralization under acidic conditions, which were resulted from fast decomposition of leaves after the first 6 months incubation. The increases in soil organic matter content, extractable K, CEC, aggregate stability and water holding capacity and the decreases in soil pH and bulk density provide favorable conditions for crop’s growth.

关键词： soil physical and chemical properties Robinia pseudoacacia Gilgit-Baltistan

The reproductive biology of a Central American cichlid Neetroplus nematopus in Lake Xiloá ,Nicaragua

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Current Zoology 2010年第1期56卷 43-51页

作者： Kenneth R.McKAYE Jeremy HALE Eric P.van den BERGHE world wide fund for nature Finland Universidad de Centroamericana Department of Mathematics Science and Technology Ave Maria University Latin American Campus

This study was conducted to provide a five-year database on the breeding seasonality and breeding biology of a Central American cichlid fish Neetroplus nematopus, a biparental substratum-spawning cichlid that cares for its eggs, wrigglers, and fry for up to six weeks. A total of 503 breeding pairs were monitored for breeding success. Breeding pairs of N. nematopus are sexually dimorphic in size, with females averaging 39% of male body mass. Fry emerged from 85% of nesting cavities. After three weeks, only 30% of the broods were present in the nesting cavity; these broods had a 30% survival rate, giving a 9% overall survival rate. Nineteen percent of the successful parents with three-week-old broods adopted foreign fry. A consistent unimodal breeding peak in December was observed for five years. This breeding peak differed dramatically from the bimodal breeding season 20 years found in the 1970s. The effects of extensive grenade fishing practices during the 1980s might have played a substantial role in the observed change. Grenade fishing stopped in 1991, and the number ofN. nematopus pairs increased by 136% from 1990 to 1995. With increased density of breeding fish, the breeding season for this species also expanded. The balance between divergent selection due to competition for breeding sites and stabilizing selection due to predation pressure on offspring is likely to mold the breeding season for N. nematopus and other cichlids of Lake Xilofi. We suggest that brood adoption and synchrony of breeding is a strategy to reduce predation on the parent＇s own young [Current Zoology 56 （1）： 43-51 2010].

关键词： Nicaragua Cichlids Breeding Reproduction Synchrony Seasonality

Analysis of deposition and erosion of Dongting Lake by GIS

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Journal of Geographical Sciences 2001年第4期11卷 22-30页

作者： Gao Jun-feng Zhang Chen Jiang Jia-hu Huang Qun Nanjing Institute of Geography Limnology CAS world wide fund of nature

The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of them are transported into the Yangtze River in Chenglingji, which is located at the exit of the Dongting Lake, some of them deposit into drainage system in the lake region and the rest deposit into the lake. The annual mean sediment is 166,555x104 t, of which 80% come from the four channels, 18% from the four tributaries and 2% from local area, whereas 26% of the total sediments are transported into the Yangtze River and 74% deposited into the lake and the lake drainage system. Based on topographic maps of 1974, 1988 and 1998, and the spatial analysis method with geographic information system (GIS), changes in sediment deposition and erosion are studied in this paper. By overlay analysis of 1974 and 1988, 1988 and 1998, erosion and sediments deposition areas are defined. The main conclusions are: (1) sediment rate in the lake is larger than erosion rate from 1974 to 1998. The mean deposition in the lake is 0.43 m; (2) annual sediment deposition is the same between 1974-1988 and 1988-1998, but the annual volume of deposition and erosion of 1988-1998 is bigger than that in 1974-1988; (3) before the completion of the Three Gorges Reservoir, there will be 7.82x108 m3 of sediments deposited in the lake, which would make the lake silted up by 0.33 m; (4) in the lake, the deposition area is found in the north of the east Dongting Lake, the south-west of the south Dongting Lake, and the east of the west Dongting Lake; while the eroded area is in the south of the east Dongting Lake, the middle of the south Dongting Lake, the west of the west Dongting Lake, as well as Xiangjiang and Lishui river flood channels.

关键词： Dongting Lake sediment deposition and erosion spatial distribution GIS

Impact of numerous larval diets on the biology of pink bollworm Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)under laboratory conditions

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Journal of Cotton Research 2024年第1期7卷 69-78页

作者： AKHTAR Shamim ARIF Muhammad Jalal GOGI Muhammad Dildar HAQ Imran-ul Department of Entomology University of Agriculture FaisalabadPunjabPakistan Ayub Agricultural Research Institute(Entomological Research Institute) FaisalabadPunjabPakistan Department of Plant Pathology University of AgricultureFaisalabadPunjabPakistan

Background Pink bollworm,Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)has become a poten-tial pest of cotton by causing substantial yield losses around the world including *** in view the facts like limited research investigations,unavailability,and high cost of artificial diet’s constituents and their premixes,the present research investigations on the dietary aspect of *** were *** larvae of *** were reared on different diets that were prepared using indigenous *** standard/laboratory diet com-prised of wheat germ meal 34.5 g,casein 30.0 g,agar–agar 20.0 g,sucrose 10.0 g,brewer’s yeast 5.0 g,α-cellulose 1.0 g,potassium-sorbate1.5 g,niplagin 0.5 g,decavitamin 0.01 g,choline-chloride 0.06 g,maize-oil 3.30 g,honey 2.0 g,and water 730.0 *** to cotton bolls and wheat germ meal were okra seed sprouts,okra fruit,cottonseed meal,and okra seed meals,which were included in the study to introduce an efficient and economic mass-rearing *** The larval development completed in 19.68d±0.05 d with a weight of 20.18mg±0.20 mg at the fourth instar fed on the cottonseed meal-based diet instead of wheat germ meal based *** the same diet,84.00%±4.00%,17.24 mg±0.03 mg,and 7.76d±0.06 d were recorded as pupae formation,pupal weight,and pupal duration,*** emergence,76.00%±1.00%was recorded from pupae collected from larvae raised on cottonseed meal-based *** male and female moths lived for 40.25d±0.10 d,and 44.34d±0.11 d,*** deposited 21.28±0.04 eggs per day with the viability of 65.78%±0.14%.The larval mortal-ity at the fourth instar was 37.20%±1.36%and malformed pupation of 12.00%±1.41%was *** of wheat germ meal with that of local meals(cottonseed and okra seed)in the standard laboratory diet has saved 463.80 to 467.10 PKR with 1.62 to 1.63 cost economic returns,*** This research is of novel nature as it provides a concis

关键词： Artificial diets Cottonseed meal Laboratory rearing Pectinophora gossypiella Wheat germ meal