Hydrodynamic control of microphytoplankton bloom in a coastal sea     

K Narasimha Murty  Nittala S Sarma  Sudarsana Rao Pandi  Gundala Chiranjeevulu  Rayaprolu Kiran  R Muralikrishna 《Journal of Earth System Science》2017,126(6):82

The influence of hydrodynamics on phytoplankton bloom occurrence/formation has not been adequately reported. Here, we document diurnal observations in the tropical Bay of Bengal’s mid-western shelf region which reveal microphytoplankton cell density maxima in association with neap tide many times more than what could be accounted for by solar insolation and nutrient levels. When in summer, phytoplankton cells were abundant and the cell density of Guinardia delicatula reached critical value by tide caused zonation, aggregation happened to an intense bloom. Mucilaginous exudates from the alga due to heat and silicate stress likely promoted and stable water column and weak winds left undisturbed, the transient bloom. The phytoplankton aggregates have implication as food resource in the benthic region implying higher fishery potential, in carbon dioxide sequestration (carbon burial) and in efforts towards improving remote sensing algorithms for chlorophyll in the coastal region.  相似文献   

Explosive felsic volcanism at Palaeo-Mesoproterozoic boundary from Vindhyan Supergroup,Son Valley,Central India—Evidences of crustal contamination     

Meenal Mishra  Shinjana Sen  Kiran Kumari 《Geochemistry International》2017,55(5):474-488

Vindhyan basin witnessed a widespread explosive type of felsic volcanism at Palaeo-Mesoproterozoic boundary which is manifested as Chopan porcellanite shale. This is exposed as a linear belt along the Son valley in Central India. Porcellanite shale is pyroclastics deposit comprising strongly welded to unwelded ignimbrites. CIA values coupled with A–CN–K systematics provide strong evidence regarding their igneous origin and proximity of the source. The pyroclastics are rhyodacitic to rhyolitic in nature. The enriched LREE, LILE, depleted HFSE and incompatible element ratios such as Nb/Th, La/Sm and Zr/Nb indicate contamination and mixing between mantle-derived rocks and the average continental crust. Five distinct phases of volcanic activity have been identified based on field observations and petrological evidences. Pyroclastics at various stratigraphic levels indicate repeated occurrences of intrabasinal felsic volcanism, pointing to episodic extension, rifting and eruption over a period of time. The present studies have suggested that volcanic activity in Son valley and pyroclastic detritus resulted from a common chamber due to the rejuvenation and activation of deep seated faults like Son-Narmada lineament.  相似文献   

Using the Relative Operating Characteristic to Quantify Certainty in Prediction of Location of Land Cover Change in India   总被引：4，自引：0，他引：4  

R Gil Pontius Jr  Kiran Batchu 《Transactions in GIS》2003,7(4):467-484

This paper describes a methodology by which modelers, ecologists and planners can quantify the certainty in predicting the location of change for a given quantity of change. The specification of the quantity of a land cover category and the specification of the location of a land cover category are two distinct fundamental concepts in geographical analysis. It is crucial that scientists have appropriate quantitative tools to analyze each of these two concepts independently of one another. This paper gives methods whereby a scientist can convert a map of relative propensity for disturbance to a map of probability of future disturbance, based on a quantifiable validation of a map's predictive ability. The required inputs are: (1) maps that show a Boolean categorical variable at times 0, 1 and 2, (2) a technique to create a map that shows the relative propensity for membership in the Boolean category, and (3) a predicted proportion of the category at time 3.  相似文献   

Geotechnical properties of stabilised Indian red earth     

P. V. Sivapullaiah  H. Lakshmi Kantha  K. Madhu Kiran 《Geotechnical and Geological Engineering》2003,21(4):399-413

Locally available soils amended with sufficient bentonite are generally used for construction of liners for water and waste retention facilities. The amount of bentonite required to keep the hydraulic conductivity low varies with the nature of the local soil. Many studies have shown that bentonite content higher than 20% by weight is not usually required. This is also the case with Indian red earth containing predominantly quartz and kaolinite minerals. Incorporating bentonite, though keeps the hydraulic conductivity of soil low, increases the swelling and shrinkage potential; increases the loss of strength due to reduction in cohesion. This paper aims to improve the geotechnical properties of red earth and bentonite mixture with lime or cement. The studies reveal that the geotechnical properties of red earth with 20% by weight bentonite stabilised with 1% by weight of lime or cement are greatly enhanced, particularly after curing for 28 days. it has been shown that the early gain in strength is better with cement whereas its long-term strength gain is better with lime.  相似文献   

Terrain mapping camera for Chandrayaan-1     

A. S. Kiran Kumar  A. Roy Chowdhury 《Journal of Earth System Science》2005,114(6):717-720

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Analysis of Terra Modis satellite data for Ecological Impact Assessment (EcIA) studies     

T. R. Kiran Chand  K. Madhavi Latha  K. V. S. Badarinath  M. S. R. Murthy 《Journal of the Indian Society of Remote Sensing》2005,33(3):457-463

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Studies on urban heat islands using envisat AATSR data   总被引：1，自引：0，他引：1  

K. V. S. Badarinath  T. R. Kiran Chand  K. Madhavilatha  V. Raghavaswamy 《Journal of the Indian Society of Remote Sensing》2005,33(4):495-501

Urbanization has significant effects on local weather and climate and among these effects one of the most familiar is the urban heat island, for which the temperatures of the central urban locations are several degrees higher than those of nearby rural areas of similar elevation. Satellite data provides important inputs for estimating regional surface albedo and evapotranspiration required in the studies related to surface energy balance. Present study describes the analysis of day and night ENVISAT-AATSR satellite data for Urban heat island and surface thermal inertia. Field campaigns have been conducted in synchronous with the satellite data over pass for validating the surface temperature estimated from AATSR data. Satellite derived surface temperature values are within ±1° C from ground measured values. Heat island formations in urban regions of Hyderabad and environs can be clearly seen in the night time data with core urban regions showing high temperatures. Apparent thermal inertia derived from AATSR day and night data sets have shown typical variations over urban regions.  相似文献   

Simulation of monsoon boundary-layer processes using a regional scale nested grid model     

Kiran Alapaty  Sethu Raman  R. V. Madala 《Boundary-Layer Meteorology》1994,67(4):407-426

A nested grid regional model with a high vertical resolution in the atmospheric boundary layer is used to simulate various atmospheric processes during an active monsoon period. A turbulence kinetic energy closure scheme is used to predict the boundary-layer structure. Model predictions indicate different structures of the boundary layer over land and oceans, as observed. Significant diurnal variation in boundary-layer structure and associated processes is predicted over land and negligible variations over oceans. The Somali jet over the Arabian Sea is well predicted. Location of the predicted monsoon depression and the associated rainfall are in good agreement with the observations. Also, predicted rainfall and its spatial distribution along the west coast of India are in good agreement with the observations.  相似文献   

Geo-spatial assessment of community vulnerability to flood along the Ravi River,Ravi Town,Lahore, Pakistan     

Mahmood  Shakeel  Hamayon  Kiran 《Natural Hazards》2021,106(3):2825-2844

Natural Hazards - Pakistan is exposed to hydro-meteorological and geological hazards. Flood is one of the hydro-meteorological hazards, and so far 25 major floods have occurred in Indus River...  相似文献   

Stability of breakwater defenced by a seaward submerged reef     

Kiran G. Shirlal  Subba Rao  Venkata Ganesh  Manu 《Ocean Engineering》2006,33(5-6):829-846

The stability of a uniformly sloped conventional rubble mound breakwater defenced by a seaward submerged reef is investigated using physical model studies. Regular waves of wide ranging heights and periods are used. Tests are carried out for different spacings between two rubble mound structures (X/d=2.5–13.33) and for different relative heights (h/d=0.625–0.833) and relative widths (B/d=0.25–1.33) of the reef. It is observed that a reef of width (B/d) of 0.6–0.75 constructed at a seaward distance (X/d) of 6.25–8.33 breaks all the incoming waves and dissipates energy and protects the breakwater optimally.  相似文献