GIS-based impact assessment of land-use changes on groundwater quality: study from a rapidly urbanizing region of South India   总被引：4，自引：0，他引：4  

Haris H. Khan  Arina Khan  Shakeel Ahmed  Jerome Perrin 《Environmental Earth Sciences》2011,63(6):1289-1302

This study attempts to assess the influence of changing land-use patterns on the groundwater quality of the hard rock aquifer system in the Maheshwaram watershed, near Hyderabad, India. The study area is a rapidly urbanizing region with land development progressing at a fast pace. To study the impact of this rapid urbanization and overall land-use transition, a groundwater quality index (GQI) was prepared within a geographical information system (GIS). The GQI integrates the different water quality parameters to give a final index value that can be used for spatio-temporal comparisons. The land-use transitions were closely monitored from 2003 to 2008 using multispectral satellite images. The land-use pattern has changed drastically with an increase in the built-up area at the expense of other land uses. The analysis reveals a rapid deterioration of groundwater quality related mainly to the increase in built-up land with unsewered sanitation and poultry farms. Seasonal variability of the groundwater quality was also assessed. Mean GQI decreased from 84.16 to 83.26 over a period of 5 years from 2003 to 2008, while seasonal variability of water quality increased. GQI and Seasonal Variability of water quality were integrated in GIS to yield a groundwater sustainability map, in terms of water quality. Zones of sustainable and unsustainable groundwater use were demarcated for better decision making related to municipal land allotment in this rapidly urbanizing region.  相似文献   

阿尔金断裂带对青藏高原北部生长、隆升的制约   总被引：62，自引：3，他引：59  

李海兵  杨经绥  许志琴  孙知明  Paul TAPPONNIER 《地学前缘》2006,13(4):59-79

大量的同位素年代学证据表明(古)阿尔金断裂带可能形成于三叠纪,后又经历了侏罗纪、白垩纪的强烈左旋走滑活动,自印度板块与欧亚大陆碰撞后阿尔金断裂再次活动。主要的走滑活动发生在:(1)245~220Ma;(2)180~140Ma;(3)120~100Ma;(4)90~80Ma;(5)60~45Ma;(6)渐新世至中新世;(7)上新世至更新世以及(8)全新世。沿阿尔金断裂带,伴随左旋走滑活动形成一系列的逆冲断裂和正断裂,反映走滑过程中伴随隆升作用的存在,并且形成自北向南包括祁连山、大雪山、党河南山、柴北缘山、祁漫塔格山和昆仑山,表明阿尔金断裂带制约着青藏高原北部的生长和隆升。阿尔金断裂带东、西两端的白垩纪和新生代火山活动是断裂走滑活动的响应。  相似文献   

Analysis of nocturnal air temperature in districts using mobile measurements and a cooling indicator     

Leconte  François  Bouyer  Julien  Claverie  Rémy  Pétrissans  Mathieu 《Theoretical and Applied Climatology》2017,130(1-2):365-376

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Tunable diode laser measurements of trace gases during the 1988 Polarstern cruise and intercomparisons with other methods     

G. W. Harris  D. Klemp  T. Zenker  J. P. Burrows  B. Mathieu 《Journal of Atmospheric Chemistry》1992,15(3-4):315-326

Measurements of NO₂, HCHO, and H₂O₂ were made by the highly specific method of mid infra-red absorption spectroscopy using tunable diode lasers (TDLAS) during the 1988 Polarstern expedition. The TDLAS data are compared to those obtained during the cruise using less direct methods. Southern Hemisphere NO₂ levels suggest nett photochemical destruction of O₃ in the boundary layer. Northern Hemisphere HCHO averaged 0.47±0.2 ppbv; the HCHO measurements are used in a simple calculation to estimate OH noontime maxima of 3–6×10⁶ cm^-3.  相似文献   

Erratum to: 3D thermal history and maturity modelling of the Levant Basin and its eastern margin,offshore–onshore Lebanon     

Samer Bou Daher  Mathieu Ducros  Pauline Michel  Nicolas Hawie  Fadi H. Nader  Ralf Littke 《Arabian Journal of Geosciences》2016,9(9):550

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Intercomparison of statistical and dynamical downscaling models under the EURO- and MED-CORDEX initiative framework: present climate evaluations     

Pradeebane Vaittinada Ayar  Mathieu Vrac  Sophie Bastin  Julie Carreau  Michel Déqué  Clemente Gallardo 《Climate Dynamics》2016,46(3-4):1301-1329

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The ancient glaciers of the Midland Counties of England     

W. Jerome Harrison 《Proceedings of the Geologists' Association. Geologists' Association》1898,15(9):400-408

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Sketch of the geology of the Birmingham District: With special reference to the long excursion of 1898     

C. Lapworth  W.W. Watts  W. Jerome Harrison 《Proceedings of the Geologists' Association. Geologists' Association》1898,15(9):313-IN3

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Preparation and characterization of subcellular fractions suitable for studies of xenobiotic metabolism from leaf sheaths of a marine seagrass: Posidonia oceanica (Linnaeus) Delile     

Dounia Hamoutene  Anne Mathieu  Paul Hofmann  Jean-Pierre Salaun  Marc Lafaurie 《Marine environmental research》1995,39(1-4)

The capacity of the mammalian liver microsomal P-450-dependent systems to metabolize a wide variety of endogenous and exogenous compounds is thought to reflect the presence of multiple forms of P-450 haemoproteins with broad and overlapping substrate specificity. In plants, the functions and specificity of cytochrome P-450 systems are less well known.This study was designed to prepare and characterize subcellular fractions from fresh sheaths (basal parts of leaves) of a mediterranean seagrass Posidonia oceanica (Linnaeus) Delile, the aim being the preparation of a microsomal fraction suitable for studying xenobiotic metabolism. The purity of the different fractions obtained by centrifugation, as well as the recovery of different organelles, was determined using enzyme markers (cytochrome c oxidase, alkaline phosphatase, glucose-6-phosphatase) and morphological examination by transmission electron microscopy. Some assays of enzymes involved in xenobiotic metabolism (cytochrome c reductase, laurate hydroxylase, ethoxyresorufin O-deethylase and glutathione-S-transferase) were also performed on different fractions of the preparation. The subcellular distribution for drug metabolism and marker enzymes showed a loss of endoplasmic reticulum in the pellet obtained after the first centrifugation, but the microsomal fraction was relatively free of mitochondria and fragments of the plasma membrane.Some assays are still being performed to avoid the small loss of endoplasmic reticulum experienced with the first pellet. However, the microsomes prepared in this study from sheaths of Posidonia oceanica appear suitable for further investigation of xenobiotic metabolism.  相似文献   

Simulation of upper-ocean biogeochemistry with a flexible-composition phytoplankton model: C, N and Si cycling in the western Sargasso Sea     

Mathieu Mongin  David M. Nelson  Philippe Pondaven  Mark A. Brzezinski  Paul Trguer 《Deep Sea Research Part I: Oceanographic Research Papers》2003,50(12):1445-1480

We report the first application of a biogeochemical model in which the major elemental composition of the phytoplankton is flexible, and responds to changing light and nutrient conditions. The model includes two phytoplankton groups: diatoms and non-siliceous picoplankton. Both fix C in accordance with photosynthesis-irradiance relationships used in other models and take up NO₃⁻ and NH₄⁺ (and Si(OH)₄ for diatoms) following Michaelis-Menten kinetics. The model allows for light dependence of photosynthesis and NO₃⁻ uptake, and for the observed near-total light independence of NH₄⁺ uptake and Si(OH)₄ uptake. It tracks the resulting C/N ratios of both phytoplankton groups and Si/N ratio of diatoms, and permits uptake of C, N and Si to proceed independently of one another when those ratios are close to those of nutrient-replete phytoplankton. When the C/N or Si/N ratio of either phytoplankton group indicates that its growth is limited by N, Si or light, uptake of non-limiting elements is controlled by the content of the limiting element in accordance with the cell-quota formulation of Droop (J. Mar. Biol. Ass. U.K 54 (1974) 825).We applied this model to the Bermuda Atlantic Time-series Study (BATS) site in the western Sargasso Sea. The model was tuned to produce vertical profiles and time courses of [NO₃⁻], [NH₄⁺] and [Si(OH)₄] that are consistent with the data, by adjusting the kinetic parameters for N and Si uptake and the rate of nitrification. The model then reproduces the observed time courses of chlorophyll-a, particulate organic carbon and nitrogen, biogenic silica, primary productivity, biogenic silica production and POC export with no further tuning. Simulated C/N and Si/N ratios of the phytoplankton indicate that N is the main growth-limiting nutrient throughout the thermally stratified period and that [Si(OH)₄], although always limiting to the rate of Si uptake by diatoms, seldom limits their growth rate. The model requires significant nitrification in the upper 200 m to yield realistic time courses and vertical profiles of [NH₄⁺] and [NO₃⁻], suggesting that NO₃⁻ is not supplied to the upper water column entirely by physical processes. A nitrification-corrected f-ratio (f_NC), calculated for the upper 200 m as: (NO₃⁻ uptake—nitrification)/(NO₃⁻ uptake+NH₄⁺ uptake) has annual values ranging from only 0.05–0.09, implying that 90–95% of the N taken up annually by phytoplankton is supplied by biological regeneration (including nitrification) in the upper 200 m. Reported discrepancies between estimates of organic C export based on seasonal chemical changes and POC export measured at the BATS site can be almost completely resolved if there is significant regeneration of NO₃⁻ via organic-matter decomposition in the upper 200 m.  相似文献