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1.
Rashid Umar M. Muqtada A. Khan Izrar Ahmed Shakeel Ahmed 《Journal of Earth System Science》2008,117(1):69-78
The Kali-Hindon inter-stream region extends over an area of 395 km2 within the Ganga-Yamuna interfluve. It is a fertile tract for sugarcane cultivation. Groundwater is a primary resource for
irrigation and industrial purposes. In recent years, over-exploitation has resulted in an adverse impact on the groundwater
regime. In this study, an attempt has been made to calculate a water balance for the Kali-Hindon inter-stream region. Various
inflows and outflows to and from the aquifer have been calculated. The recharge due to rainfall and other recharge parameters
such as horizontal inflow, irrigation return flow and canal seepage were also evaluated. Groundwater withdrawals, evaporation
from the water table, discharge from the aquifer to rivers and horizontal subsurface outflows were also estimated. The results
show that total recharge into the system is 148.72 million cubic metres (Mcum), whereas the total discharge is 161.06 Mcum,
leaving a deficit balance of −12.34 Mcum. Similarly, the groundwater balance was evaluated for the successive four years.
The result shows that the groundwater balance is highly sensitive to variation in rainfall followed by draft through pumpage.
The depths to water level are shallow in the canal-irrigated northern part of the basin and deeper in the southern part. The
pre-monsoon and post-monsoon water levels range from 4.6 to 17.7 m below ground level (bgl) and from 3.5 to 16.5 m bgl respectively.
It is concluded that the groundwater may be pumped in the canal-irrigated northern part, while withdrawals may be restricted
to the southern portion of the basin, where intense abstraction has led to rapidly falling water table levels. 相似文献
2.
The Krishni–Yamuna interstream area is a micro-watershed in the Central Ganga Plain and a highly fertile track of Western
Uttar Pradesh. The Sugarcane and wheat are the major crops of the area. Aquifers of Quaternary age form the major source of
Irrigation and municipal water supplies. A detailed hydrogeological investigation was carried out in the study area with an
objective to assess aquifer framework, groundwater quality and its resource potential. The hydrogeological cross section reveals
occurrence of alternate layers of clay and sand. Aquifer broadly behaves as a single bodied aquifer down to the depth of 100 m bgl
(metre below ground level) as the clay layers laterally pinch out. The depth to water in the area varies between 5 and 16.5 m bgl.
The general groundwater flow direction is from NE to SW with few local variations. An attempt has been made to evaluate groundwater
resources of the area. The water budget method focuses on the various components contributing to groundwater flow and groundwater
storage changes. Changes in ground water storage can be attributed to rainfall recharge, irrigation return flow and ground
water inflow to the basin minus baseflow (ground water discharge to streams or springs), evapotranspiration from ground water,
pumping and ground water outflow from the basin. The recharge is obtained in the study area using Water table fluctuation
and Tritium methods. The results of water balance study show that the total recharge in to the interstream region is of the
order of 185.25 million m3 and discharge from the study area is of the order of 203.24 million m3, leaving a deficit balance of −17.99 million m3. Therefore, the present status of groundwater development in the present study area has acquired the declining trend. Thus,
the hydrogeological analysis and water balance studies shows that the groundwater development has attained a critical state
in the region. 相似文献
3.
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5.
Ali Sajid Haider Rashid Abbas Wahid Basharat Muhammad Reicherter Klaus 《Natural Hazards》2021,106(3):2437-2460
Natural Hazards - The Karakoram Highway links north Pakistan with southwest China. It passes through unique geomorphological, geological and tectonic setting. This study focused 200-km-long section... 相似文献
6.
Muhammad Khurshid Mohammad Nafees Abdullah Khan Mehmet Somuncu Ashfaq Ahmad Khan Wajid Rashid 《地理学报(英文版)》2019,29(10):1758-1770
Journal of Geographical Sciences - Pastoralism is a viable socio-economic system-shaped by landless and agro-pastoral communities in many pastoral regions of the world. This system is mainly based... 相似文献
7.
This paper reviews the socio-economic and ecological context of Fijian reef fisheries. This review is deemed necessary because improved understanding of the state and trends of Fiji's coral reef fisheries on a national level is required for designing an effective management plan for Fiji's inshore reef fisheries. The most important point that emerges from our review is that despite numerous studies of Fiji's reef fisheries, the current status of reef-associated fisheries at the national level is still uncertain due, mainly, to the lack of dependable data on the subsistence fisheries. This in turn leads to uncertainty about how the continuation of fishing, in particular, fishing focused on target species for the coral reef resources trade, will affect fishing communities and the ecosystem. 相似文献
8.
Brian N. Tissot Barbara A. Best Eric H. Borneman Andrew W. Bruckner Cara H. Cooper Heather D’Agnes Timothy P. Fitzgerald Amanda Leland Susan Lieberman Amy Mathews Amos Rashid Sumaila Teresa M. Telecky Frazer McGilvray Brian J. Plankis Andrew L. Rhyne Glynnis G. Roberts Benjamin Starkhouse Todd C. Stevenson 《Marine Policy》2010
As the world’s largest importer of marine ornamental species for the aquaria, curio, home décor, and jewelry industries, the United States has an opportunity to leverage its considerable market power to promote more sustainable trade and reduce the effects of ornamental trade stress on coral reefs worldwide. Evidence indicates that collection of some coral reef animals for these trades has caused virtual elimination of local populations, major changes in age structure, and promotion of collection practices that destroy reef habitats. Management and enforcement of collection activities in major source countries such as Indonesia and the Philippines remain weak. Strengthening US trade laws and enforcement capabilities combined with increasing consumer and industry demand for responsible conservation can create strong incentives for improving management in source countries. This is particularly important in light of the March 2010 failure of the parties to the Convention on International Trade in Endangered Species (CITES) to take action on key groups of corals. 相似文献
9.
10.
The Primrose Prospect lies 48 km east of Sable Island on the Scotian Shelf below 80 km of water. The subsurface geology is characterized by the presence of Jurassic salt that has pierced the early Cretaceous sediments and uplifted late Cretaceous and early Tertiary beds to provide localized structural closure, shale compaction, and anomalously high heat gradients in the younger sediments overlying the salt mass.The reservoir rocks interbedded with the compacted shales contain wet gas, condensate, and 31° API oil. The organic matter in these shales, which consists essentially of amorphous material, has undergone thermal alteration and maturation at a very shallow depth, a condition not apparent in coeval beds elsewhere in the area. This localized alteration of the organic matter is considered to have occurred in response to the thermal and pressure effects of the underlying halokinetic structure and could have resulted in the genesis of the mature hydrocarbons. 相似文献