935 resultados para Northern Areas (Pakistan)--Maps
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specially prepared for the Foreign Department, from India ; published under direction of Colonel F. B. Longe, R. E., Surveyor General of India.
Comparison of Grouper assemblages in northern areas of the wider Caribbean: a preliminary assessment
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Structures transverse/sub-transverse to the shoreline have been identified and characterized on the precambrian basement outcrop on the continent adjacent to the northern Santos Basin. These structures were analyzed from images of digital elevation model SRTM 90m by extracting NW-SE lineaments that intersect the NE-SW foliation. The lineaments were selected, classified into 48 segments that extend toward offshore, and correlated with basin structures. In the basin 25 2D seismic sections, 12 well logs and data from potential methods were interpreted, identifying the key stratigraphic levels and the major structures. Structural maps of each horizon were generated. Six transfer faults (FTs) were recognized and named FT-1 to FT-6, whose extensions correspond to continental lineaments named FC1 to FC6. The FTs are related to the basin deformation and evolution. In seismic sections, these faults have lateral slip in flower structures, displacement inversions from normal at the top to reverse at the base, abrupt changes in thickness or even disappearance of the seismic reflectors. The structural map of the Basement and Top of the Rift shows control of some depocenters by faults and displacements in some areas. The maps of potential methods indicate that there are pronounced anomaly shifts in some areas, associated with FTs. Some seismic sections indicate reactivation of FTs when they intersect horizons from the basement until the most recent layers. The 3D integration of data facilitated the observation of the FT extensions in the continent discontinuity.
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The aim of this study was to identify future distribution areas and propose actions to preserve passion fruit pollination service under a scenario of future climate change. We used four species of Xylocopa bees that are important for passion fruit pollination in Brazilian Tropical Savannas. We also used the known forage plant species (33 species) that are associated with this same area, since passion fruit flowers provide only nectar for bees and only during their blossoming period. We used species distribution modeling to predict the potential areas of occurrence for each bee and plant based on the current day distribution and a future climate scenario (moderate projections of climate change to 2050). We used a geographic information system to classify the models and to analyze the future areas for both groups of species. The current day distribution map showed that Xylocopa and plant species occurred primarily in the southern and central-eastern areas of the Brazilian Tropical Savannas. In the north, Xylocopa species only occurred in a small area between the states of Maranhão and Piauí while forage plant species were only observed in the northern part of the Tocantins State. However, both future scenarios (bees and plants) showed a shift in distribution, with occurrence predominantly detected in the northern areas of Brazilian Tropical Savannas. Possible conservation areas and the use of appropriate agricultural practices were suggested to ensure the maintenance of the bee/plant focal species.
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This study investigated the diarrhoea seasonality and its potential drivers as well as potential opportunities for future diarrhoea control and prevention in China. Data on weekly infectious diarrhoea cases in 31 provinces of China from 2005 to 2012, and data on demographic and geographic characteristics, as well as climatic factors, were complied. A cosinor function combined with a Poisson regression was used to calculate the three seasonal parameters of diarrhoea in different provinces. Regression tree analysis was used to identify the predictors of diarrhoea seasonality. Diarrhoea cases in China showed a bimodal distribution. Diarrhoea in children <5 years was more likely to peak in fall-winter seasons, while diarrhoea in persons > = 5 years peaked in summer. Latitude was significantly associated with spatial pattern of diarrhoea seasonality, with peak and trough times occurring earlier at high latitudes (northern areas), and later at low latitudes (southern areas). The annual amplitudes of diarrhoea in persons > = 5 years increased with latitude (r = 0.62, P<0.001). Latitude 27.8° N and 38.65° N were the latitudinal thresholds for diarrhoea seasonality in China. Regional-specific diarrhoea control and prevention strategies may be optimal for China. More attention should be paid to diarrhoea in children <5 years during fall-winter seasons.
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The prospect of climate change has revived both fears of food insecurity and its corollary, market opportunities for agricultural production. In Australia, with its long history of state-sponsored agricultural development, there is renewed interest in the agricultural development of tropical and sub-tropical northern regions. Climate projections suggest that there will be less water available to the main irrigation systems of the eastern central and southern regions of Australia, while net rainfall could be sustained or even increase in the northern areas. Hence, there could be more intensive use of northern agricultural areas, with the relocation of some production of economically important commodities such as vegetables, rice and cotton. The problem is that the expansion of cropping in northern Australia has been constrained by agronomic and economic considerations. The present paper examines the economics, at both farm and regional level, of relocating some cotton production from the east-central irrigation areas to the north where there is an existing irrigation scheme together with some industry and individual interest in such relocation. Integrated modelling and expert knowledge are used to examine this example of prospective climate change adaptation. Farm-level simulations show that without adaptation, overall gross margins will decrease under a combination of climate change and reduction in water availability. A dynamic regional Computable General Equilibrium model is used to explore two scenarios of relocating cotton production from south east Queensland, to sugar-dominated areas in northern Queensland. Overall, an increase in real economic output and real income was realized when some cotton production was relocated to sugar cane fallow land/new land. There were, however, large negative effects on regional economies where cotton production displaced sugar cane. It is concluded that even excluding the agronomic uncertainties, which are not examined here, there is unlikely to be significant market-driven relocation of cotton production.
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ENGLISH: The rate of growth of tropical tunas has been studied by various investigators using diverse methods. Hayashi (1957) examined methods to determine the age of tunas by interpreting growth patterns on the bony or hard parts, but the results proved unreliable. Moore (1951), Hennemuth (1961), and Davidoff (1963) studied the age and growth of yellowfin tuna by the analysis of size frequency distributions. Schaefer, Chatwin and Broadhead (1961), and Fink (ms.), estimated the rate of growth of yellowfin tuna from tagging data; their estimates gave a somewhat slower rate of growth than that obtained by the study of length-frequency distributions. For the yellowfin tuna, modal groups representing age groups can be identified and followed for relatively long periods of time in length-frequency graphs. This may not be possible, however, for other tropical tunas where the modal groups may not represent identifiable age groups; this appears to be the case for skipjack tuna (Schaefer, 1962). It is necessary, therefore, to devise a method of estimating the growth rates of such species without identifying the year classes. The technique described in this study, hereafter called the "increment technique", employs the measurement of the change in length per unit of time, with respect to mean body length, without the identification of year classes. This technique is applied here as a method of estimating the growth rate of yellowfin tuna from the entire Eastern Tropical Pacific, and from the Commission's northern statistical areas (Areas 01-04 and 08) as shown in Figure 1. The growth rates of yellowfin tuna from Area 02 (Hennemuth, 1961) and from the northern areas (Davidoff, 1963) have been described by the technique of tracing modal progressions of year classes, hereafter termed the "year class technique". The growth rate analyses performed by both techniques apply to the segment of the population which is captured by tuna fishing vessels. The results obtained by both methods are compared in this report. SPANISH: La tasa del crecimiento de los atunes tropicales ha sido estudiada por varios investigadores quienes usaron diversos métodos. Hayashi (1957) examinó los métodos para determinar la edad de los atunes interpretando las marcas del crecimiento de las partes óseas o duras, pero los resultados no han demostrado eficacia. Moore (1951), Hennemuth (1961) y Davidoff (1963) estudiaron la edad y el crecimiento del atún aleta amarilla por medio del análisis de las distribuciones de la frecuencia de tamaños. Schaefer, Chatwin y Broadhead (1961) y Fink (Ms.), estimaron la tasa del crecimiento del atún aleta amarilla valiéndose de los datos de la marcación de los peces; ambos estimaron una tasa del crecimiento algo más lenta que la que se obtiene mediante el estudio de las distribuciones de la frecuencia de longitudes. Para el atún aleta amarilla, los grupos modales que representan grupos de edad pueden ser identificados y seguidos durante períodos de tiempo relativamente largos en los gráficos de la frecuencia de longitudes. Sin embargo, ésto puede no ser posible para otros atunes tropicales para los cuales los grupos modales posiblemente no representan grupos de edad identificables; este parece ser el caso para el barrilete (Schaefer, 1962). Consecuentemente, es necesario idear un método para estimar las tasas del crecimiento de las mencionadas especies sin necesidad de identificar las clases anuales. La técnica descrita en este estudio, en adelante llamada la "técnica incremental", emplea la medida del cambio en la longitud por unidad de tiempo, con respecto al promedio de la longitud corporal, sin tener que identificar las clases anuales. Esta técnica se aplica aquí como un método para estimar la tasa del crecimiento del atún aleta amarilla de todo el Pacífico Oriental Tropical, y de las áreas estadísticas norteñas de la Comisión (Areas 01-04 y 08), como se muestra en la Figura 1. Las tasas del crecimiento del atún aleta amarilla del Area 02 (Hennemuth, 1961) y de las áreas del norte (Davidoff, 1963), han sido descritas por medio de una técnica que consiste en delinear las progresiones modales de las clases anuales, en adelante llamada la "técnica de la clase anual". Los análisis de la tasa del crecimiento llevados a cabo por ambas técnicas se refieren al segmento de la población capturada por embarcaciones pesqueras de atún. Los resultados obtenidos por ambos métodos se comparan en este informe.
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PREFACE: Four species of menhaden, Brevoortia spp., are found along the Atlantic and Gulf of Mexico coasts of the United States. The Atlantic menhaden, B. tyrannus, is found from Nova Scotia, Can., to West Palm Beach, Fla.; the yellowfin menhaden, B. smithi, is found from Cape Lookout, N. C., to the Mississippi River Delta, La.;the Gulf menhaden, B. patronus, is found from Cape Sable, Fla., to Veracruz, Mex.; and the finescale menhaden, B. gunteri, is found from the Mississippi River Delta, La., to Campeche, Mex. Menhaden are euryhaline species that inhabit coastal and inland tidal waters. Spawning occurs principally at sea (in northern areas some spawning occurs in bays and sounds). Eggs hatch at sea and the larvae are moved to estuaries by ocean currents where they metamorphose and develop as juveniles.
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目前全球缺水、水污染、洪涝灾害以及水土流失仍然非常严重,尤其在我国北方地区。流域水文模型可用来进行不同需水管理的情景分析,为解决我国水问题提供科学依据。分布式水文模型是流域水文模型的发展方向,具有显著特点:1)应用前景广泛,不仅可以模拟流域水文过程,还可以协助模拟泥沙或污染物的运移过程,为水利工程设计、水土保持、环境保护等领域提供技术支持;2)能够预测流域土地利用或气候变化下的流域水文响应过程变化,为管理部门提供决策支持;3)模型所需要的参数全部具有物理意义,可通过实际测量确定,适合模拟实测系列较短或是无观测流域的水文过程;4)对于目前国际水文界的前沿问题—水文尺度转换提供了一种有效的解决途径。 然而分布式水文模型还不完善,如1)真实性问题。对一些水文过程和边界条件还不确定。2)尺度转换问题。目前很少考虑尺度对参数有效性的影响。3)检验问题。还无法判断对有些难以测量的水文状态变量的模拟正确与否。4)计算时间和数据存储的问题。有些分布式水文模型虽然具有很强的水文物理基础和完善的模型结构,但是计算时间过长和(或)数据存储过大,难以应用。上述问题的核心就是对分布式水文模型的核心—单元水文模型的研究不够,需要为进一步完善单元水文模型进行研究。 本文采用饱和入渗理论、Saint-Venant方程、Richards方程、Penman-Monteith方程等等构建了以有限差分法求解的适用于森林流域的单元水文模型,并通过实验室模拟试验和坡地径流场资料进行了验证,主要结论为: 通过不同坡度和不同雨强下的室内坡面产汇流实验模拟,表明:该模型模拟的坡面流和壤中流过程与实测过程基本一致,峰现时间、径流历时、峰值流量、出流总量模拟值与实测值的相对误差均较小,基本小于10%。模型的模拟精度较高,实用性较强,为深入研究壤中流机制和改进流域降雨-径流模型提供了理论依据。 通过坡地径流观测场实测资料的验证,表明:该模型模拟的坡面流过程精度较高,累计流量的精度更高于小时过程的精度,离差系数、效率系数、确定系数均较理想,具有应用价值,有助于改善分布式水文模型在森林流域的模拟效果。
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A methodology for analyzing the solar access and its influence on both air temperature and thermal comfort of the urban environment was here developed by applying the potentiality of GIS tools. Urban canyons in a specific area of a Brazilian medium sized city were studied. First, a computational algorithm was applied in order to allow the determination of sky view factors (SVF) and sun-paths in urban canyons. Then, air temperatures in 40 measurement points were collected within the study area. Solar radiation values of these canyons were determined and subsequently stored in a GIS database. The creation of thermal maps for the whole neighbourhood was possible due to a statistical treatment of the data, by promoting the interpolation of values. All data could then be spatially cross-examined. In addition, thermal comfort maps for summer and winter periods were generated. The methodology allowed the identification of thermal tendencies within the neighbourhood, what can be useful in the conception of guidelines for urban planning purposes.
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Context. The complex shape of comet 67P and its oblique rotation axis cause pronounced seasonal effects. Irradiation and hence activity vary strongly. Aims. We investigate the insolation of the cometary surface in order to predict the sublimation of water ice. The strongly varying erosion levels are correlated with the topography and morphology of the present cometary surface and its evolution. Methods. The insolation as a function of heliocentric distance and diurnal (spin dependent) variation is calculated using >10(5) facets of a detailed digital terrain model. Shading, but also illumination and thermal radiation by facets in the field of view of a specific facet are iteratively taken into account. We use a two-layer model of a thin porous dust cover above an icy surface to calculate the water sublimation, presuming steady state and a uniform surface. Our second model, which includes the history of warming and cooling due to thermal inertia, is restricted to a much simpler shape model but allows us to test various distributions of active areas. Results. Sublimation from a dirty ice surface yields maximum erosion. A thin dust cover of 50 pm yields similar rates at perihelion. Only about 6% of the surface needs to be active to match the observed water production rates at perihelion. A dust layer of 1 mm thickness suppresses the activity by a factor of 4 to 5. Erosion on the south side can reach more than 10 m per orbit at active spots. The energy input to the concave neck area (Hapi) during northern summer is enhanced by about 50% owing to self-illumination. Here surface temperatures reach maximum values along the foot of the Hathor wall. Integrated over the whole orbit this area receives the least energy input. Based on the detailed shape model, the simulations identify "hot spots" in depressions and larger pits in good correlation with observed dust activity. Three-quarters of the total sublimation is produced while the sub-solar latitude is south, resulting in a distinct dichotomy in activity and morphology. Conclusions. The northern areas display a much rougher morphology than what is seen on Imhotep, an area at the equator that will be fully illuminated when 67P is closer to the Sun. Self-illumination in concave regions enhance the energy input and hence erosion. This explains the early activity observed at Hapi. Cliffs are more prone to erosion than horizontal, often dust covered, areas, which leads to surface planation. Local activity can only persist if the forming cliff walls are eroding. Comet 67P has two lobes and also two distinct sides. Transport of material from the south to the north is probable. The morphology of the Imhotep plain should be typical for the terrains of the yet unseen southern hemisphere.
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En febrero de 1998 se observó en cultivos de pimiento y ají de Mendoza (Argentina) muerte anticipada de plantas con severos daños en la producción. La magnitud del problema motivó una prospección en los principales oasis de la provincia, a fin de describir la sintomatología, conocer su dispersión, estimar los daños causados y recolectar material para realizar estudios en laboratorio tendientes a confirmar su etiología. Se constató que la afección se encontraba distribuida en todos los oasis del centro y norte. La sintomatología en hojas se caracterizó por la presencia en la cara adaxial de manchas amarillentas, de forma circular de 15 a 20 mm de diámetro, con puntuaciones necróticas, con tendencia a presentarse en anillos concéntricos. En la cara abaxial, generalmente las lesiones eran acompañadas de un micelio blanco tenue. Posteriormente siguió una severa defoliación. La producción disminuyó notablemente y además en pimiento los frutos fueron afectados por escaldaduras de sol y perdieron su valor comercial. A partir de aislamientos de pimiento y ají, mantenidos en plantas de brincos (Impatiens balsamina L.), se inocularon plantas sanas y se logró reproducir la enfermedad en condiciones de invernáculo.
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Well-preserved diatoms are present in high sedimentation rate Pleistocene cores retrieved on Ocean Drilling Program (ODP) Legs 151, 152, 162 and IMAGES cruises of R/V Marion Dufresne from the North Atlantic. Investigation of the stratigraphic occurrence of diatom species shows that the youngest diatom event observed in the area is the last occurrence (LO) of Proboscia curvirostris (Jousé) Jordan and Priddle. P. curvirostris is a robust species that can easily be identified in the sediments, and therefore can be a practical biostratigraphic tool. We have mapped its areal distribution, and found that it stretches from 40°N to 80°N in the North Atlantic. Further, we have correlated the LO P. curvirostris to the oxygen isotope records of six cores to refine the age of this biostratigraphic event. The extinction of P. curvirostris is latitudinally diachronous through Marine Isotope Stages (MIS) 9 to 8 within the North Atlantic. This is closely related to the paleoceanography of the area. P. curvirostris first disappeared within interglacial MIS 9 (324 ka) from the northern areas that are most sensitive to climatic forcing, like the East Greenland current and the sea-ice margin. It survived in mid-North Atlantic until the conditions of the MIS 8 (glaciation) became too severe (260 ka). In the North Pacific at ODP Site 883 the LO P. curvirostris falls within MIS 8. The observed overlap in age between the North Atlantic and the North Pacific strongly suggests that the extinction of P. curvirostris is synchronous between these oceans.
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Fine-grained sediment depocenters on continental shelves are of increased scientific interest since they record environmental changes sensitively. A north-south elongated mud depocenter extends along the Senegalese coast in mid-shelf position. Shallow-acoustic profiling was carried out to determine extent, geometry and internal structures of this sedimentary body. In addition, four sediment cores were retrieved with the main aim to identify how paleoclimatic signals and coastal changes have controlled the formation of this mud depocenter. A general paleoclimatic pattern in terms of fluvial input appears to be recorded in this depositional archive. Intervals characterized by high terrigenous input, high sedimentation rates and fine grain sizes occur roughly contemporaneously in all cores and are interpreted as corresponding to intensified river discharge related to more humid conditions in the hinterland. From 2750 to 1900 and from 1000 to 700 cal a BP, wetter conditions are recorded off Senegal, an observation which is in accordance with other records from NW-Africa. Nevertheless, the three employed proxies (sedimentation rate, grain size and elemental distribution) do not always display consistent inter-core patterns. Major differences between the individual core records are attributed to sediment remobilization which was linked to local hydrographic variations as well as reorganizations of the coastal system. The Senegal mud belt is a layered inhomogeneous sedimentary body deposited on an irregular erosive surface. Early Holocene deceleration in the rate of the sea-level rise could have enabled initial mud deposition on the shelf. These favorable conditions for mud deposition occur coevally with a humid period over NW-Africa, thus, high river discharge. Sedimentation started preferentially in the northern areas of the mud belt. During mid-Holocene, a marine incursion led to the formation of an embayment. Afterwards, sedimentation in the north was interrupted in association with a remarkable southward shift in the location of the active depocenter as it is reflected by the sedimentary architecture and confirmed by radiocarbon dates. These sub-recent shifts in depocenters location are caused by migrations of the Senegal River mouth. During late Holocene times, the weakening of river discharge allowed the longshore currents to build up a chain of beach barriers which have forced the river mouth to shift southwards.