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In Balochistan, Agriculture is dominated by small-scale farmers and the apple production sector is confronted with the chronic constraint of low output per unit of input. Although some agricultural policies have been implemented in this province, studies on effectiveness and impacts of such policies over apple production and farmers’ performance are still limited. This study is an effort to bridge the research gap on this potential crop in the plateau by investigating technical and scale efficiency of 181 officially designated small-scale apple farmers in mountainous district Mastung in Balochistan; then explored factors that underlie differences in production inefficiency. A two-stage input-oriented Data Envelopment Analysis (DEA) methodology was employed to evaluate technical and scale efficiency followed by truncated bootstrapped regression framework to analyze the correlative determinants to efficiency. Average technical and scale efficiencies of larger landholders were higher than medium and small landholders. Analysis indicated that there is still ample scope for inefficient sample farmers to reduce the input use by 33% without compromising the given yield level. Maximum contributions to the total input savings were from the use of urea, farm yard manure (FYM) and labor-use. Farmer’s experience, farm ownership, irrigation constraints, and farmer’s access to trainings, credit and extension services significantly affected apple farmers’ technical efficiency. Based on the findings of this study, strategies are suggested to enhancing efficiencies by farmers’ capacity development through effective extension services and trainings and provision of adequate credit. 相似文献
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The alpine treeline ecotone is an important component of mountain ecosystems of the Nepal Himalaya; it plays a vital role in the livelihood of indigenous people, and provides ecosystem services. However, the region faces a problem of paucity of data on treeline characteristics at the regional and landscape scales. Therefore, we used Remote Sensing (RS), and Geographic Information Science (GIS) approaches to investigate cross-scale interactions in the treeline ecotone. Additionally, European Space Agency land cover map, International Center for Integrated Mountain Development (ICIMOD) land cover map, ecological map of Nepal, and United States Geological Survey Shuttle Radar Topography Mission-Digital Elevation Model were used to analyze treeline pattern at the regional scale. Digital Globe high-resolution satellite imagery of Barun (eastern Nepal) and Manang (central Nepal) were used to study treeline patterns at the landscape scale. Treeline elevation ranges from 3300-4300 m above sea level. Abies spectabilis, Betula utilis, and Pinus wallichiana are the main treeline-forming species in the Nepal Himalaya. There is an east to west treeline elevation gradient at the regional scale. No slope exposure is observed at the regional scale; however, at the landscape scale, slope exposure is present only in a disturbed area (Manang). Topography and human disturbance are the main treeline controlling factor in Barun and Manang respectively. 相似文献
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Rakesh K. DUMKA Bahadur S. KOTLIA Kireet KUMAR Gokul S. SATYAL Lalit M. JOSHI 《山地科学学报》2014,11(1):41-50
The foremost Global Positioning System(GPS) derived measurements in the Kumaun Himalaya indicate that most of the crustal motion of the Indian plate is accommodating towards the base as well as on the hanging wall of Main Central Thrust(MCT).Deformation pattern within the Kumaun Himalaya varies from south to north and indicates maximum deformation rate near MCT.Our study,based on the campaign mode GPS survey during 2003- 2006,reveals that the area between north of North Almora Thrust(NAT) and at the base of Great Himalaya registers maximum strain rate,which is lowered towards the Trans Himadri Fault(THF).The GAMIT-GLOBK processed campaign data of the area show that currently,the Himalayan Frontal Fault(HFF) and Main Boundary Thrust(MBT) are locked with the Indian plate,and a 6.7 ± 2.5 mm/yr of horizontal shortening is taking place between the Lesser Himalaya and Peninsular India. 相似文献
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The lithostratigraphy, depositional environment and age of the Marwar Supergroup have been reviewed in the light of report
of δ13C depletion recorded in the carbonates of the Bilara Group (middle part of Marwar Supergroup) and discovery of trilobite-like
trace fossils from the ·Red bedsŽ of Nagaur Group (upper part of Marwar Supergroup). The δ13C depletion observed in Bilara carbonates is not a result of glaciation rather due to rapid burial and poor water circulation
in the low energy water of the protected basin. Secondly, the trace fossils are, in fact, traces of notostracan crustaceans
found in shallow fluvial and shallow lacustrine environment. The present paper also records a spiral, burrowing trace-fossil,
possibly Gyrolithes, from a cross-bedded sandstone of the Jodhpur Group. 相似文献
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Mapping soil erosion susceptibility using remote sensing and GIS: a case of the Upper Nam Wa Watershed,Nan Province,Thailand 总被引:7,自引:0,他引:7
K. C. Krishna Bahadur 《Environmental Geology》2009,57(3):695-705
Land degradation is still a very common problem in the mountains of Asia because of inappropriate land use practice in steep
topography. Many studies have been carried out to map shifting cultivation and areas susceptible to soil erosion. Mostly,
estimated soil loss is taken as the basis to classify the level of soil loss susceptibility of area. Factors that influence
soil erosion are: rainfall erosivity, soil erodibility, slope length and steepness, crop management and conservation practices.
Thus the reliability of estimated soil loss is based on how accurately the different factors were estimated or prepared. As
each and every small pixel of our earth surface is different from one area to another, the manner in which the study area
was discretized into smaller homogenous sizes and how the most accurate and efficient technique were adopted to estimate the
soil loss are very important. The purpose of this study is to produce erosion susceptibility maps for an area that has suffered
because of shifting cultivation located in the mountainous regions of Northern Thailand. For this purpose, an integrated approach
using RS and GIS-based methods is proposed. Data from the Upper Nam Wa Watershed, a mountainous area of the Northern Thailand
were used. An Earth Resources Data Analysis System (ERDAS) imagine image processor has been used for the digital analysis
of satellite data and topographical analysis of the contour data for deriving the land use/land cover and the topographical
data of the watershed, respectively. ARCInfo and ARCView have been used for carrying out geographical data analysis. The watershed
was discretized into hydrologically, topographically, and geographically homogeneous grid cells to capture the watershed heterogeneity.
The soil erosion in each cell was calculated using the universal soil loss equation (USLE) by carefully determining its various
parameters and classifying the watershed into different levels of soil erosion severity. Results show that during the time
of this study most of the areas under shifting cultivation fell in the highest severity class of susceptibility. 相似文献
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Jonathan Corcoran Gary Higgs David Rohde Prem Chhetri 《Journal of Geographical Systems》2011,13(2):193-226
Fires in urban areas can cause significant economic, physical and psychological damage. Despite this, there has been a comparative
lack of research into the spatial and temporal analysis of fire incidence in urban contexts. In this paper, we redress this
gap through an exploration of the association of fire incidence to weather, calendar events and socio-economic characteristics
in South-East Queensland, Australia using innovative technique termed the quad plot. Analysing trends in five fire incident
types, including malicious false alarms (hoax calls), residential buildings, secondary (outdoor), vehicle and suspicious fires,
results suggest that risk associated with all is greatly increased during school holidays and during long weekends. For all
fire types the lowest risk of incidence was found to occur between one and six a.m. It was also found that there was a higher
fire incidence in socially disadvantaged neighbourhoods and there was some evidence to suggest that there may be a compounding
impact of high temperatures in such areas. We suggest that these findings may be used to guide the operations of fire services
through spatial and temporal targeting to better utilise finite resources, help mitigate risk and reduce casualties. 相似文献
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The integration of different GNSS constellations offers considerable opportunities to improve Precise Point Positioning (PPP) performance. Being aware of the limited number of the alternatives that utilize the potential advantages of the multi-constellation and multi-frequency GNSS, we developed a MATLAB-based GNSS analysis software, named PPPH. PPPH is capable of processing GPS, GLONASS, Galileo and BeiDou data, and forming their different combinations depending on user’s preference. Thanks to its user-friendly graphical interface, PPPH allows users to determine a variety of processing options and parameters. In addition to an output file including the estimated parameters for every single epoch, PPPH also presents several analyzing and plotting tools for evaluating the results, such as positioning error, tropospheric zenith total delay, receiver clock estimation, satellite number, dilution of precisions. On the other hand, we conducted experimental tests to both validate the performance of PPPH and assess the potential benefits of multi-GNSS on PPP. The results indicate that PPPH provides comparable PPP solution with the general standards and also contributes to the improvement of PPP performance with the integration of multi-GNSS. Consequently, we introduce a GNSS analysis software that is easy to use, has a robust performance and is open to progress with its modular structure. 相似文献
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Seasonal variation of stable isotopes in precipitation of Kathmandu Valley on the southern slope of Himalaya was carried out to understand the controlling mechanism of amount and temperature effect on the basis of one year stable isotope data from 2010 to 2011. Highly depleted isotope values in major rainy period are obtained just after the onset of precipitation in summer, which accounts for "amount effect" due to saturation isotopic compositions in high moisture condition, whereas, the higher values in winter are indicative to regional vapors (temperature effect) recycling of various sources. An abrupt depletion of isotope values in mid-June, indicates the onset date of monsoon precipitation, by the replacement of winter air mass with southern monsoon. Thus, precipitation isotopes are a tool revealing the onset date of summer monsoon and temporal features of variability, in local and regional monsoons precipitations. A comparison of long term monthly values of δ 18 O, temperature, and precipitation with GNIP δ 18 O data shows the temporal variations of stable isotopes are mostly controlled by amount and temperature effects. During summer monsoon, the amount effects are stronger for high values of precipitation (R=0.7) and altitude effect appears for low moisture in late rainy season, thus from December to June (winter to pre-monsoon) the controlling features of isotopes remains under the temperature effect. A temporal rate of temperature effect is derived as 0.04‰ per year which indicates a dry signal of atmospheric condition and a temperature relation δ 18 O=(0.371±0.08)T+(0.156±0.05) is obtained from this analysis. The meteoric water lines of Kathmandu before and after monsoon onset of 2011, are found as δD=(4.36±0.3)δ 18 O+(15.66±1.2) and δD=(6.91±0.2)δ 18 O (7.92±2.26) from lab samples result, and δD=9.2δ 18 O+11.725 and δD=8.53δ 18 O+16.65 from GNIP data, which lacks the consistency both for slopes and intercepts values for the study period. The mean lapse rate values of δ 18 O and δD from GNIP data are obtained as 0.002‰/m and 0.015 ‰/m, which indicate the altitudinal effects in regional precipitation of the southern slope of Himalayas. This study estimates new stable isotopes data in recent precipitation using simple methodology which can be important for regional precipitation monitoring systems, environmental change and paleo-climatic studies. 相似文献
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