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61.
Ashley McCrea-Strub Dirk Zeller Ussif Rashid Sumaila Jay Nelson Andrew Balmford Daniel Pauly 《Marine Policy》2011
While the recurrent cost of managing marine protected areas (MPAs) has been documented and estimated, there has been virtually no attempt to quantify the cost of establishing MPAs in the first place. This lack of attention is likely the result of the complexity of the process, involving often uncoordinated efforts of a multitude of governmental and non-governmental entities over a protracted period of time with no clear start and end-point. Using information gathered from a representative subset of MPAs worldwide, this paper presents the first attempt to identify and describe the various components, and explore potential predictors of the total funds spent in the course of establishment. The thirteen MPAs studied vary in size (from <1 to >360,000 km2), location (including near- and offshore in both developed and developing countries), objectives and degree of protection. Variation in MPA start-up costs is shown to be most significantly related to both MPA size and the duration of the establishment phase. Development of a method to estimate the potential cost of establishing proposed MPAs should play a crucial role in the conservation planning process. 相似文献
62.
Sebastian Heinz Andrea Merloni Tiziana Di Matteo Rashid Sunyaev 《Astrophysics and Space Science》2005,300(1-3):15-21
The scale invariance model (Heinz, S. and Sunyaev, R.A.: 2003, MNRAS 343, L59) can be used to derive robust scaling relations between the radio luminosity from accreting black holes and the black
hole mass and accretion rate. These relations agree well with the recently found “fundamental plane” of black hole activity
(Merloni, A., Heinz, S. and Di Matteo, T.: 2003, MNRAS 345, 1057). This relation provides a new, powerful tool for the comparison of jets from black holes of different masses and accretion
rates. The regression coefficients of this relation contain information about the nature of the X-ray emission mechanism driving
the correlation. We argue that X-ray synchrotron emission from the base of the jets is unlikely to be the dominant contribution
to the X-ray spectrum in most of the sources. 相似文献
63.
Harun A. Rashid Harry H. Hendon Matthew C. Wheeler Oscar Alves 《Climate Dynamics》2011,36(3-4):649-661
Predictions of the Madden?CJulian oscillation (MJO) are assessed using a 10-member ensemble of hindcasts from POAMA, the Australian Bureau of Meteorology coupled ocean?Catmosphere seasonal prediction system. The ensemble of hindcasts was initialised from observed atmosphere and ocean initial conditions on the first of each month during 1980?C2006. The MJO is diagnosed using the Wheeler-Hendon Real-time Multivariate MJO (RMM) index, which involves projection of daily data onto the leading pair of eigenmodes from an analysis of zonal winds at 200 and 850?hPa and outgoing longwave radiation (OLR) averaged about the equator. Forecasts of the two component (RMM1 and RMM2) index are quantitatively compared with observed behaviour derived from NCEP reanalyses and satellite OLR using the bivariate correlation skill, root-mean-square error (RMSE), and measures of the MJO amplitude and phase error. Comparison is also made with a simple vector autoregressive (VAR) prediction model of RMM as a benchmark. Using the full hindcast set, we find that the MJO can be predicted with the POAMA ensemble out to about 21?days as measured by the bivariate correlation exceeding 0.5 and the bivariate RMSE remaining below ~1.4 (which is the value for a climatological forecast). The VAR model, by comparison, drops to a correlation of 0.5 by about 12?days. The prediction limit from POAMA increases by less than 2?days for times when the MJO has large initial amplitude, and has little sensitivity to the initial phase of the MJO. The VAR model, on the other hand, shows a somewhat larger increase in skill for times of strong MJO variability and has greater sensitivity to initial phase, with lower skill for times when MJO convection is developing in the Indian Ocean. The sensitivity to season is, however, greater for POAMA, with maximum skill occurring in the December?CJanuary?CFebruary season and minimum skill in June?CJuly?CAugust. Examination of the MJO amplitudes shows that individual POAMA members have slightly above observed amplitude after a spin-up of about 10?days, whereas examination of the MJO phase error reveals that the model has a consistent tendency to propagate the MJO slightly slower than observed. Finally, an estimate of potential predictability of the MJO in POAMA hindcasts suggests that actual MJO prediction skill may be further improved through continued development of the dynamical prediction system. 相似文献
64.
D. Purushotham Mehnaz Rashid Mahjoor Ahmad Lone A. Narsing Rao Shakeel Ahmed E. Nagaiah Farooq A. Dar 《Journal of the Geological Society of India》2013,81(3):385-396
Anthropogenic activities in Maheshwaram watershed have deteriorated water, air and soil quality during the last ten years due to rapid urbanisation and industrial development. Maheshwaram watershed experienced drastic changes in land use pattern, being very close to the Hyderabad city. Base-line data was collected during post monsoon season (October-November) of 2010 in Maheshwaram watershed to assess the impacts of change in land use, urbanisation and industrialisation on air, water and soil quality for Environmental Impact Assessment (EIA). Air samples were analysed for Suspended Particulate Matter (SPM) and Respirable Suspended Particulate Matter (RSPM). Groundwater samples were analysed for pH; EC; TDS; TH; cations, anions and heavy metals viz., Fe, Mn, Al, Si, V, Cr, As, Sr, Rb, Se, Ba, Li, B, Be, Co, Ni, Zn, Cd, and Pb using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Analysed data were compared with the National and International Standards and subjected to Factor Analysis (FA) for six chemical variables to assess and characterise hydro-chemical processes. A comparison of the results of groundwater samples with WHO and BIS guidelines show that most of the groundwater samples are heavily contaminated with heavy metals like lead, chromium, nickel, barium, aluminium, boron and selenium, which was quantified and presented in the form of spatial variation diagrams prepared using ArcGIS. 9.3.1. Similarly the results of air samples compared with the Central Pollution Control Board, Ministry of Environment and Forests, Government of India guidelines show that most of the air samples for residential, rural and industrial areas are contaminated by SPM and RSPM. 相似文献
65.
Ruzinoor Che Mat Abdul Rashid Mohamed Shariff Biswajeet Pradhan Ahmad Rodzi Mahmud Mohd Shafry Mohd Rahim 《Arabian Journal of Geosciences》2013,6(12):4881-4889
The objective of this paper is to discuss the effectiveness of visualizing online 3D terrain draped with different satellite imageries. The topographic data of the study area were obtained from the contour maps of Universiti Putra Malaysia, Selangor, Malaysia. The high resolution satellite imageries used in this project involving QUICKBIRD (0.6 m resolution), IKONOS (1 m resolution), and SPOT5 (5 m resolution). R2V software was used for editing the contour data, whereas Arc GIS was used for overlaying the imageries over the 3D terrain data. Then the data were exported into Virtual Reality Markup Language to compare the effectiveness of different satellite imageries based on the data file size, imageries size, number of images tile, loading time during office hours (from 8 a.m. to 5 p.m.) and out of office hours (after 5 p.m.), frame rate per second, and visualization quality. The results revealed that IKONOS satellite imageries are better for an effective online 3D terrain visualization utilizing GIS data even though it has lower resolution compared to QUICKBIRD. 相似文献
66.
Up to one-third of commercial fishery stocks may be overfished at present. By analyzing catch trends and applying an empirical relationship derived from stock assessments, this article tracks the geographic spread of overfishing at the country level in terms of lost catch and lost revenue, from the start of industrialized fishing in 1950-2004. The results tell a cautionary tale of serial depletion to meet the ever-rising demand for fish. Examining country losses with respect to fishery management reveals that overcapacity and excess fishing effort are widespread, but also that recent trends towards sustainability can stabilize or reverse losses (e.g. for Norway, Iceland, the US, Canada, Australia, and New Zealand). Global trade effectively masks the successive depletion of stocks, so that without decisive action to reduce fishing effort, many more stocks will suffer and undernourishment impacts for the major exporting, food-deficit nations will only magnify. 相似文献
67.
美国俄亥俄州土壤有机碳密度空间分布(英文) 总被引:2,自引:1,他引:1
Historical database of National Soil Survey Center containing 1424 geo-referenced soil profiles was used in this study for estimating the organic carbon(SOC) for the soils of Ohio,USA.Specific objective of the study was to estimate the spatial distribution of SOC density(C stock per unit area) to 1.0-m depth for soils of Ohio using geographically weighted regression(GWR),and compare the results with that obtained from multiple linear regression(MLR).About 80% of the analytical data were used for calibration and 20% for validation.A total of 20 variables including terrain attributes,climate data,bedrock geology,and land use data were used for mapping the SOC density.Results showed that the GWR provided better estimations with the lowest(3.81 kg m 2) root mean square error(RMSE) than MLR approach.Total estimated SOC pool for soils in Ohio ranged from 727 to 742 Tg.This study demonstrates that,the local spatial statistical technique,the GWR can perform better in capturing the spatial distribution of SOC across the study region as compared to other global spatial statistical techniques such as MLR.Thus,GWR enhances the accuracy for mapping SOC density. 相似文献
68.
Mureed Hussain Nisar Ahmed Wang Yan Chun Perveiz Khalid Azhar Mahmood Sajid Rashid Ahmad Umair Rasool 《Journal of the Geological Society of India》2017,89(3):331-338
The lower Indus basin is one of the largest hydrocarbon producing sedimentary basins in Pakistan. It is characterized by the presence of many hydrocarbon-bearing fields including clastic and carbonates proven reservoirs from the Cretaceous to the Eocene age. This study has been carried out in the Sanghar oil field to evaluate the hydrocarbon prospects of basal sand zone of lower Goru Formation of Cretaceous by using complete suite of geophysical logs of different wells. The analytical formation evaluation by using petrophysical studies and neutron-density crossplots unveils that litho-facies mainly comprising of sandstone. The hydrocarbons potentialities of the formation zone have been characterized through various isoparameteric maps such as gross reservoir and net pay thickness, net-to-gross ratio, total and effective porosity, shaliness, and water and hydrocarbons saturation. The evaluated petrophysical studies show that the reservoir has net pay zone of thickness range 5 to 10 m, net-togross ratio range of 0.17 to 0.75, effective porosity range of 07 to 12 %, shaliness range of 27 to 40 % and hydrocarbon saturation range of 12 to 31 %. However, in the net pay zone hydrocarbon saturation reaches up to 95%. The isoparametric charts of petrophysically derived parameters reveal the aerial distribution of hydrocarbons accumulation in basal sand unit of the lower Goru Formation which may be helpful for further exploration. 相似文献
69.
70.
Rashid Umar Izrar Ahmed Fakhre Alam Mohammad Muqtada Khan 《Environmental Geology》2009,58(6):1295-1300
The present study was undertaken to assess major ion chemistry of groundwater in parts of the Central Ganga Plain and observe
seasonal variations in its chemical quality. Systematic sampling was carried out during November 2005 and June 2006. The major
ion chemistry of groundwater shows large variations, so much so that at times the meteoric signature seems to be completely
obliterated. In many samples the concentrations of SO4, NO3 and F are above the permissible limit for human consumption. The graphical treatment of major ion chemistry helps in identifying
four types of groundwater. All possible ionic species such as NaCl, KCl, NaHCO3, NaSO4, KNO3, NaNO3, CaHCO3, MgHCO3, MgSO4 are likely to occur in groundwater system. The observed chemical variations may be attributed to sediment water interaction,
ion exchange, dissolution mechanisms and anthropogenic influences such as application of fertilizers and effluents from sugar
factories and paper mills. A general increase in TDS is observed in samples during June 2006. The increase in salinity is
attributed to evaporation from water table, irrigation return flows, anthropogenic activities and below average rainfall in
2005 and 2006.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献