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121.
1INTRODUCTION NepentheswhichareknownlocallyinPeninsular Malaysiaasperiukkerabelongtoamonogenericfami lyNepenthaceae.Atpresent,atotalofninespecies(excludingnaturalhybrids)arerecordedfromPenin sularMalaysia.Ofthese,fourspeciesareendemic,whilsttheotherfivespeciesarefoundoutsidethepen insula.Thespeciescanarbitrarilybeclassifiedinto thelowlandspeciesandthehighlandspecies(Clarke,2002;Shivas,1984;Kurata,1976).Threespeciesarefoundinthehighlandhabitatscom monlyatanelevationofabove1000mforaboves…  相似文献   
122.
The aim of this study was to transform the rain into flow in the basin of Wadi Djendjen by using a simulation model in absence of the continuous measurements of the flow. The obtained results indicated and confirmed the strong adaptability of this model with varied hydroclimatic situations. The validation process showed an interesting result, which lead to conclude that the model is well calibrated and has a good performance to be used for the basins with Mediterranean climate. The obtained results for the simulation by the GR2M model over the studied period (1973–1986) showed that there no significant difference between the obtained value for the yearly average flow (197.70 hm3) and that measured at Missa hydrometric station (200.80 hm3), which allow us to estimate quantitatively the flow in Missa hydrometric station. While, for the period of 2000–2012, the results showed that the yearly average flow value (171.90 hm3), is significantly different (reduction of 15% for 12 years), in comparison with that measured at Missa hydrometric station (200.80 hm3). This can be due to the dryness which struck the region since 2000, and the local degradation of the forest ecosystem, which has considerably affected the runoff surface.  相似文献   
123.
Siripatana  Adil  Le Maitre  Olivier  Knio  Omar  Dawson  Clint  Hoteit  Ibrahim 《Ocean Dynamics》2020,70(8):1103-1127
Ocean Dynamics - Bayesian inference with coordinate transformations and polynomial chaos for a Gaussian process with a parametrized prior covariance model was introduced in Sraj et al. (Comput...  相似文献   
124.
In this study, we investigated the spatial characteristics of the rate of soil distribution and the mechanism of major element migration in a typical karst hillslope in Guangxi Province, Southwestern China. Soil redistribution was examined using 137Cs technique under different hillslope components. With the combination of geochemical methods, the migration characteristics of major elements in soils of three hillslope components in both the horizontal and vertical directions were determined. Thirty-seven soil samples were collected and analyzed for 137Cs and the major elements were determined. By using the profile distribution model the mean soil redistribution rates were found to be -17.01, 0.40 and -23.30 t ha-1 yr-1 in the summit (BYSD), shoulder (BYSY) and toeslope (BYSJ) components of the studied hillslope, respectively. In comparison to BYSD, the sesquioxides of Fe2O3 and TiO2 tend to be enriched, whereas the alkalis (CaO, MgO, Na2O and K2O) tend to be depleted, both in the shoulder and toeslope components. Due to human and animal activities, the contents of CaO, MgO, K2O and Na2O have somewhat increased within the topsoil. The results indicated that 137Cs activities are significantly correlated with clay particles and organic matter, and are affected by the pedogenic process and vegatation. Overall, it maybe necessary to use techniques such as 137Cs to investigate soil erosion with the combination of geochemical methods.  相似文献   
125.
This study is designed to determine ammonia and nitrite excretion by Penaeus monodon 25–30 day old postlarvae fed with different diets (artificial and natural). Shrimps were fed with Chaetoceros calcitrans (phytoplankton), chironomid larvae (benthos), Brachionus sp. (rotifer) and artificial diet. In the control treatment, shrimps were not fed. The highest concentration of ammonia was excreted by shrimps fed with artificial diet and the lowest by that of control treatment. All treatments except where shrimps fed on C. calcitrans showed a sudden increase in ammonia-N excretion after 36 h. C. calcitrans contributed to high ammonia excretion only after 61 h. Shrimps fed with Brachionus sp. (rotifer) showed significantly higher nitrite excretion rate compared to other treatments. Shrimps fed on C. calcitrans depicted the lowest nitrite excretion. This experiment indicated that nitrogenous excretion was predominant in shrimps fed with artificial diets. Live food like algae and chironomids, despite a high protein content, contribute to low nitrogenous excretion and hence pose less adverse effects on water quality compared to artificial diets.  相似文献   
126.
We analyze and integrate energy andforestry carbon mitigation scenarios for Mexicobetween the year 1994 and 2010. The energy optionsrange from efficient end-use technologies to renewabletechnologies for electricity generation. Forestryoptions include avoiding deforestation through themanagement of native forests, and two afforestationoptions: restoration plantations and agroforestrysystems. The methodology utilized to evaluatedifferent energy and forestry scenarios is based on a`bottom up' model. In the year 2010, total carbonemissions will reach 879 Tg of CO2, of which 83%comes from energy consumption. The total carbonmitigation potential reaches 348 Tg of CO2 by2010, 62% of which comes from forestry options.Mitigation costs range from $–45.9/ton CO2 to$106.4/ton CO2. Several options, particularlyconcerning energy technologies, are cost effectivefrom a national perspective. In each sector, differentbarriers can hinder the implementation of mitigationalternatives.  相似文献   
127.
We examined the diet of juvenile fish of four species – Eucinostomus melanopterus (Gerreidae), Ethmalosa fimbriata (Clupeidae), Monodactylus sebae (Monodactylidae), and Sarotherodon melanotheron (Cichlidae) – between their appearance on the nursery ground and the end of the recruitment season, when they began to shift to deeper parts of the estuary. Fish were collected from the Sine-Saloum, an inverse estuary in Senegal, West Africa. Sampling was conducted at six sites located along the salinity gradient. The study was conducted in the context of an inverse estuary where increasing salinity leads to the disappearance of mangroves.  相似文献   
128.
Application of the Linkam TS1400XY heating stage to melt inclusion studies   总被引:1,自引:0,他引:1  
Melt inclusions (MI) trapped in igneous phenocrysts provide one of the best tools available for characterizing magmatic processes. Some MI experience post-entrapment modifications, including crystallization of material on the walls, formation of a vapor bubble containing volatiles originally dissolved in the melt, or partial to complete crystallization of the melt. In these cases, laboratory heating may be necessary to return the MI to its original homogeneous melt state, followed by rapid quenching of the melt to produce a homogeneous glass phase, before microanalyses can be undertaken. Here we describe a series of heating experiments that have been performed on crystallized MI hosted in olivine, clinopyroxene and quartz phenocrysts, using the Linkam TS1400XY microscope heating stage. During the experiments, we have recorded the melting behaviors of the MI up to a maximum temperature of 1360°C. In most of the experiments, the MI were homogenized completely (without crystals or bubbles) and remained homogeneous during quenching to room temperature. The resulting single phase MI contained a homogeneous glass phase. These tests demonstrate the applicability of the Linkam TS1400XY microscope heating stage to homogenize and quench MI to produce homogeneous glasses that can be analyzed with various techniques such as Electron Microprobe (EMP), Secondary Ion Mass Spectrometry (SIMS), Laser ablation Inductively Coupled Plasma Mass Spectrometry (LA ICP-MS), Raman spectroscopy, FTIR spectroscopy, etc. During heating experiments, the optical quality varied greatly between samples and was a function of not only the temperature of observation, but also on the amount of matrix glass attached to the phenocryst, the presence of other MI in the sample which are connected to the outside of the crystal, and the existence of mineral inclusions in the host.  相似文献   
129.
Limestone bedrock topography has complex phenomena and highly relief subsurface topography due to the presence of karstic features. Geotechnical and environmental problems arise whenever foundations are established on the surface of the limestone bedrock or within the overburden soils. Geographical information system (GIS) and remote sensing are emerging as powerful techniques widely applicable in natural resources management to detect land use changes and devise strategies based on these changes. The study focuses on using aerial photography for the detection of changes and effects of mining on geomorphology, especially the use of sequential images that allows to detect changes taken place from time to time, by using. Volumetric Surface Movement Spatiotemporal Data Model (VSMSDM) application has been employed to create karst terrain surface movements and visualized 3D information in the Virtual Geographical Information Systems (VGIS). VSMSDM application was implemented by developing prototype of visualization system using with integrated time in the TIN structure. The data have been collected from aerial photography in 1981 and 2004, and the results displayed that the proposed data model is able to view the changing in karst topography to detect significant landscapes and landforms changes.  相似文献   
130.
The Devasthal Fast Optical Telescope (DFOT) is a 1.3 meter aperture optical telescope, recently installed at Devasthal, Nainital. We present here the first results using an Hα filter with this telescope on a Wolf–Rayet dwarf galaxy Mrk 996. The instrumental response and the Hα sensitivity obtained with the telescope are (3.3 ± 0.3) × 10???15 erg s?1 cm?2/counts s?1 and 7.5 × 10???17 erg s?1 cm?2 arcsec?2 respectively. The Hα flux and the equivalent width for Mrk 996 are estimated as (132 ± 37) × 10?14 erg s?1 cm?2 and ~96 Å respectively. The star formation rate is estimated as 0.4 ± 0.1M yr?1. Mrk 996 deviates from the radio-FIR correlation known for normal star forming galaxies with a deficiency in its radio continuum. The ionized gas as traced by Hα emission is found in a disk shape which is misaligned with respect to the old stellar disk. This misalignment is indicative of a recent tidal interaction in the galaxy. We believe that galaxy–galaxy tidal interaction is the main cause of the WR phase in Mrk 996.  相似文献   
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