排序方式： 共有9条查询结果，搜索用时 812 毫秒
1
1.
Adnan Mohammed Sarfaraz Gani Dewan Ashraf Zannat Khatun E. Abdullah Abu Yousuf Md 《Natural Hazards》2019,99(1):425-448
Natural Hazards - The occurrence of heavy rainfall in the south-eastern hilly region of Bangladesh makes this area highly susceptible to recurrent flash flooding. As the region is the commercial... 相似文献
2.
Ahmed Md. Kawser Alam Mohammad Samsul Yousuf Abu Hena Muhammad Islam Md. Monirul 《Theoretical and Applied Climatology》2017,129(1-2):473-486
A long-term (1948 to 2012) trend of precipitation (annual, pre-monsoon, monsoon, and post-monsoon seasons) in Bangladesh was analyzed in different regions using both parametric and nonparametric approaches. Moreover, the possible teleconnections of precipitation (annual and monsoon) variability with El Niño/Southern Oscillation (ENSO) episode and Indian Ocean Dipole (IOD) were investigated using both average and individual (both positive and negative) values of ENSO index and IOD. Our findings suggested that for annual precipitation, a significant increasing monotonic trend was found in whole Bangladesh (4.87 mm/year), its western region (5.82 mm/year) including Rangpur (9.41 mm/year) and Khulna (4.95 mm/year), and Sylhet (10.12 mm/year) and Barisal (6.94 mm/year) from eastern region. In pre-monsoon, only Rangpur (2.88 mm/year) showed significant increasing trend, while in monsoon, whole Bangladesh (3.04 mm/year), Sylhet (7.17 mm/year), and Barisal (6.94 mm/year) showed similar trend. In post-monsoon, there was no significant trend. Our results also revealed that the precipitation (annual or monsoon) of whole Bangladesh and almost all of the spatial regions did not show any significant correlation with ENSO events, whereas the average IOD values showed significant correlation only in monsoon precipitation of western region. The individual positive IODs showed significant correlation in whole Bangladesh, western region, and its two divisions (Rajshahi and Khulna). So, in the context of Bangladesh climate, IOD has the more teleconnection to precipitation than that of ENSO. Our findings indicate that the co-occurrence of ENSO and IOD events may suppress their influence on each other.
相似文献3.
Prioritization of sub-watersheds based on morphometric and land use analysis using remote sensing and GIS techniques 总被引：2，自引：0，他引：2
Akram Javed Mohd Yousuf Khanday Rizwan Ahmed 《Journal of the Indian Society of Remote Sensing》2009,37(2):261-274
Watershed prioritization has gained importance in natural resources management, especially in the context of watershed management.
Morphometric analysis has been commonly applied to prioritization of watersheds. The present study makes an attempt to prioritize
sub-watersheds based on morphometric and land use characteristics using remote sensing and GIS techniques in Kanera watershed
of Guna district, Madhya Pradesh. Various morphometric parameters, namely linear and shape have been determined for each sub-watershed
and assigned ranks on the basis of value/relationship so as to arrive at a computed value for a final ranking of the sub-watersheds.
Land use/land cover change analysis of the sub-watersheds has been carried out using multi-temporal data of IRS LISS II of
1989 and IRS LISS III of 2001. The study demonstrates the significant land use changes especially in cultivated lands, open
scrub, open forest, water bodies and wastelands from 1989 to 2001. Based on morphometric and land use/land cover analysis,
the sub-watersheds have been classified into three categories as high, medium and low in terms of priority for conservation
and management of natural resources. Out of the seven sub-watersheds, two sub-watersheds viz., SW1 and SW6 qualify for high
priority, whereas SW7 has been categorised as medium priority based on the integration of morphometric and land use change
analysis. 相似文献
4.
Watershed prioritization using morphometric and land use/land cover parameters: A remote sensing and GIS based approach 总被引：4，自引：0，他引：4
Akram Javed Mohd Yousuf Khanday Subah Rais 《Journal of the Geological Society of India》2011,78(1):63-75
Jaggar watershed is a constituent of the Gambhir river basin, in eastern Rajasthan and covers an area of 352.82 km2, representing arid climate. The drainage network is dendritic to sub-dendritic pattern however parallel to sub-parallel has
also developed locally. The Jaggar watershed has been divided into fourteen sub-watersheds, designated as SW1 to SW14, for
prioritization purpose. The prioritization of the sub-watersheds has been done on the basis of morphometric analysis and land
use/land cover categories. Various morphometric parameters (linear and shape) have been determined for each sub-watershed
and assigned rank on the basis of value/relationship with erodibility so as to arrive at a compound value for final ranking
of the sub-watersheds. Land use/land cover mapping has been carried out using IRS LISS III data of 1998. Based on morphometric
and land use/land cover analysis and their ranks, the subwatersheds have been classified into four categories as very high,
high, medium and low in terms of priority for conservation and management of natural resources. The prioritization results
based on morphometry reveal that only SW7 and SW10 fall under very high priority, whereas SW6, SW11 and SW13 fall under very
high priority on the basis of land use/land cover analysis. However on the integration of morphometry and land use/land cover
only SW14 show common priority whereas rest have little or no correlation. 相似文献
5.
Land use/land cover change is a global phenomenon which reflects natural resources degradation and/or utilization. Remote sensing and GIS have been widely used to monitor such changes at watershed level. The present study evaluates the LU/LC change during 1989 - 2001 in a semi-arid watershed of central India. Geocoded satellite data of 1989 and 2001 on 1:50,000 scale, were visually interpreted to prepare thematic maps which were later digitized using ArcGIS softwares. The analysis shows that vast tracts of cultivated land have become uncultivated and at some places even converted to wasteland. However, the land under dense forest and open forest has decreased due to expansion of built-up land and other anthropogenic activities. Increase in area of uncultivated land, wasteland and decrease in cultivated land and open scrub is also supported by rainfall analysis, which shows a declining trend and a fall of 186.93 mm in average annual rainfall for 1986-2003 period. The change detection map prepared using land use/land cover of 1989 and 2001 as inputs shows that out of the total geographical area of the watershed, 25.78% of the watershed area has seen a change from one land use category to another, however rest 74.22% has remained unchanged. 相似文献
6.
Anoop A. Krishnan K.S. Yousuf P.L. Kumaran N. Harish B. Anoop V.V. Afsal M. Rajagopalan E. Vivekanandan P.K. Krishnakumar P. Jayasankar 《Estuarine, Coastal and Shelf Science》2008,76(4):909-913
The stomachs of 32 individuals of seven cetacean species incidentally caught in gill net and purseseine fisheries along Mangalore and Chennai coasts (India) between 2004 and 2006 were examined. The whole stomach (fore-gut, mid-gut and hind-gut) was examined in all cases. Prey remains (666 prey items comprising six species of teleosts, one crustacean and one squid species) were found in the stomachs of eight individuals (the remaining 24 stomachs were found to be empty). All cetaceans were found to feed mostly on teleosts with wide range of trophic levels. Based on an index that included frequency of occurrence, percentage by number and by weight, the oil sardine Sardinella longiceps was the main prey in the sample. Cetaceans appear to favour both pelagic as well as demersal prey, possibly indicating surface and benthic feeding habits. 相似文献
7.
Spectrally similar nature of land covers in a glacierized terrain hampers their automated mapping from multispectral satellite data, which may be overcome by using multisource data. In the present study, an artificial neural network (ANN)-based information extraction approach was applied for mapping the Kolahoi glacier and adjoining areas, using Landsat TM (Thematic Mapper) data and several ancillary layers such as image transformations and topographic attributes. Results reveal that ANN (highest overall accuracy (OA): 83.74%) outperforms maximum likelihood classifier (highest OA: 66.90%) and the incorporation of ancillary data into the classification process significantly enhances the mapping accuracy (>9%), particularly the addition of Near Infrared Red/Short Wave Infrared (NIR/SWIR) data to the spectral data. A nine-band combination dataset (spectral data, slope, Red/NIR and decorrelation stretch) was found to be the best multisource dataset. Results of the Z-tests (at 95% confidence level) also corroborate and statistically validate the above findings. 相似文献
8.
Land and water resources development plans are generally adopted at watershed level. Delineation of watersheds and their prioritization within large river basins requires host of terrain parameters to be studied and analysed. Chopan watershed in Central India has been studied for sub-watershed delineation and prioritization based on drainage morphometry, land use/land cover and sediment yield index analysis using remote sensing and GIS techniques. The watershed was demarcated into five sub-watersheds on the basis of drainage flow directions, contour value, slope, elevation. Geocoded satellite data of 1989 and 2001 on 1:50 000 scale were visually interpreted to prepare land use/land cover and drainage maps which were later digitized using Arcview/ArcGIS. Linear and shape aspects of the sub-watersheds were computed and used for prioritization. The results show widespread variation in drainage characteristics, land cover changes and sediment yield rates across sub-watersheds. On the basis of morphometric, land use/land cover change and sediment yield index, sub-watersheds were grouped into low, medium and high priority. A correlation of results show that SW1 and SW5 are common sub-watersheds falling under high and low priority based on morphometric, land use change analysis and SYI. The priority list of sub-watersheds will be crucial for decision making and implementation of land and water resource conservation projects. 相似文献
9.
Mallick Javed Islam Abu Reza Md. Towfiqul Ghose Bonosri Islam H. M. Touhidul Rana Yousuf Hu Zhenghua Bhat Shakeel Ahmed Pal Subodh Chandra Ismail Zulhilmi Bin 《Theoretical and Applied Climatology》2022,147(1-2):307-324
Theoretical and Applied Climatology - The rise in the frequency and magnitude of extreme temperature phenomena across the globe has led to the recurrent incidence of global climate hazards, which... 相似文献
1