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Dhia Al Bakri 《Geomorphology》1996,17(4):323-337
The coastal zone in Kuwait has been under a considerable pressure from conflicting land uses since the early 1960s, as well as from the destruction and oil pollution caused by the Gulf War. To avoid further damage and to protect the coastal heritage it is essential to adopt an environmentally sustainable management process. This paper shows how the study of coastal geomorphology can provide a sound basis for sustainable planning and management. Based on coastal landforms, sediments and processes, the coastline of Kuwait was divided into nine geomorphic zones. These zones were grouped into two main geomorphic provinces. The northern province is marked by extensive muddy intertidal flats and dominated by a depositional and low-energy environment. The southern geomorphic province is characterised by relatively steep beach profiles, rocky/sandy tidal flats and a moderate to high-energy environment. The study has demonstrated that pollution, benthic ecology and other environmental conditions of the coast are a function of coastline geomorphology, sedimentology and related processes. The geomorphological information was used to determine the coastal vulnerability and to assess the environmental impacts of development projects and other human activities. Several strategies were outlined to integrate the geomorphic approach into the management of the coastal resources. 相似文献
2.
This paper examines along-channel winds within Howe Sound, British Columbia, Canada, that occur from both the interior plateau out toward the coast as outflows and from the coast inland as inflows. First, the relationships between along-channel winds and pressure, temperature, and humidity are explored in Howe Sound–Cheakamus Valley. The pressure gradients between Pam Rocks and Squamish and Pam Rocks and Pemberton have the strongest correlations with outflow strength and that between Pam Rocks and Squamish has the strongest correlation with inflow strength. Outflows (inflows) have lower (higher) temperatures and dew point temperatures, except for the inflows in summer, which have lower dewpoint temperatures than the overall mean. Second, two case studies of outflow events are presented and described during the period of intensive observations prior to and during the Vancouver 2010 Winter Olympics. The January 2010 outflow event is caused by a zone of strong across-barrier mean sea level pressure gradient. The pressure gradient is formed behind an Arctic front that moved southward across Howe Sound. The February 2010 outflow event is caused by an approaching sea level low pressure centre from the Pacific that formed a northeast–southwest mean sea level pressure gradient across southern British Columbia. In the January case, the outflow layer is about 1.5?km deep, while it is shallower in the February case. Only the January outflow case exhibits hydraulic behaviour. 相似文献
3.
Data of hourly interplanetary plasma (field magnitude, solar wind speed, and ion density), solar (sunspot number, solar radio
flux), and geomagnetic indices (Kp, Ap) over the period 1970-2010, have been used to examine the asymmetry between the solar
field north and south of the heliospheric current sheet (HCS). A persistent yearly north-south asymmetry of the field magnitude
is clear over the considered period, and there is no magnetic solar cycle dependence. There is a weak N-S asymmetry in the
averaged solar wind speed, exhibited well at times of maximum solar activities. The solar plasma is more dense north of the
current sheet than south of it during the second negative solar polarity epoch (qA < 0). Moreover, the N - S asymmetry in solar activity (Rz) can be statistically highly significant. The sign of the average N - S asymmetry depends upon the solar magnetic polarity.
The annual magnitudes of N - S asymmetry depend positively on the solar magnetic cycle. Most of the solar radio flux asymmetries
occurred during the period of positive IMF polarity. 相似文献
4.
Contribution of diffuse sources to the sediment and phosphorus budgets in Ben Chifley Catchment,Australia 总被引：3，自引：3，他引：0
Relative contribution of different diffuse sources to the sediment and phosphorous (P) budgets in the Ben Chifley Reservoir
was estimated using a multivariate mixing model and geochemical indices and tracers. The influence of the underlying geology
on land use characteristics and the dynamics of sediment and P in the catchment were discussed. Sediments currently in transport
to the reservoir are derived mainly from areas underlain by Quaternary alluvium, accounting for 33% of the reservoir sediment
budget. A major portion of the sediments from the Quaternary alluvium originates from pasture land which also contributes
about 60% of sediment-bound P in the reservoir, followed by cropland (30%) and forest area (10%). Phosphorus-based fertiliser
contributes more than 50% of the soil P in pasture and cropland and more than 60% in forest plantation area. The remaining
P reaching the reservoir originates from natural soils (native sources). Phosphate from both fertiliser and native sources
are transported to the water courses and ultimately the reservoir as a consequence of gully, stream bank and surface erosion.
Erosion control, trapping of fertiliser runoff, establishing riparian vegetation and reducing application of P-based fertiliser
by increasing native pasture cultivation in the risk areas should be considered as management options for controlling the
impact of P and sediment in the reservoir. 相似文献
5.
Dhia Al Bakri 《Environmental Geology》2002,42(6):588-596
This article demonstrates a key role that geoscience and geoscientists could be playing in promoting sustainable catchment and resource management. A new geoscience-based approach supported by a landscape-genesis (LG) model was employed to provide an alternative approach for integrated catchment management and sustainable resource use and development. The Ben Chifley Catchment case study is used to explain the application of the approach and the landscape-genesis model. The study confirmed that lithological composition, tectonic and diagenetic processes, and landform were critical factors in determining the intrinsic properties and variation in soil type, land use, land capability, steepness of terrain, erosion, and resource degradation within the catchment. The landscape-genesis model, which is based on the geological and geomorphic genesis of the landscape, proved to be a powerful tool to predict the inherent carrying capacity and resilience of the various biophysical systems in the catchment. Although this approach is still in its infancy, its application has demonstrated that it has a strong potential in terms of undertaking sound integrated assessment, predicting potential resource degradation under different land uses, and developing sound management practices and solutions to advance the goal of ecological sustainability. 相似文献
6.
Niels Schütze Sebastian Kloss Franz Lennartz Ahmed Al Bakri Gerd H. Schmitz 《Environmental Earth Sciences》2012,65(5):1511-1521
In this contribution, we introduce a stochastic framework for decision support for optimal planning and operation of water
supply in irrigation. This consists of (1) a weather generator for simulating regional impacts of climate change on the basis
of IPCC scenarios, (2) a tailor-made evolutionary optimization algorithm for optimal irrigation scheduling with limited water
supply, (3) a mechanistic model for simulating water transport and crop growth in a sound manner, and (4) a kernel density
estimator for estimating stochastic productivity, profit, and demand functions by a nonparametric method. As a result of several
simulation/optimization runs within the framework, we present stochastic crop-water production functions (SCWPF) for different
crops which can be used as a basic tool for assessing the impact of climate variability on the risk for the potential yield
for specific crops and specific agricultural areas. A case study for an agricultural area in the Al Batinah region of the
Sultanate of Oman is used to illustrate these methodologies. In addition, microeconomic impacts of climate change and the
vulnerability of the agro-ecological system are discussed. 相似文献
7.
Chiao-Yao She David A. Krueger Rashid Akmaev Hauke Schmidt Elsayed Talaat Sam Yee 《Journal of Atmospheric and Solar》2009,71(14-15):1558-1564
During 1990–2007, there were 894 lidar observations of nocturnal mesopause region temperatures over Fort Collins, Colorado. In an earlier analysis with data to April 1997, an unexpected episodic warming, peaking in 1993 with a maximum value over 10 K, was reported and attributed to the Mount Pinatubo eruption in June 1991. With all data, long-term temperature trends from a 7-parameter linear regression analysis including solar cycle effect and long-term trends leads to a cooling of as much as 6.8 K/decade at 100 km, consistent with some reported observations but larger than model predictions. Including the observed episodic warming response in an 11-parameter nonlinear regression analysis reduces the maximum long-term cooling trends to 1.5 K/decade at 91 km, with magnitude and altitude dependences consistent with the prediction of two models, Spectral Mesosphere/Lower Thermosphere Model (SMLTM) and Hamburg Model of the Neutral and Ionized Atmosphere (HAMMONIA). In addition, the mid-latitude middle-atmospheric response to solar flux variability in Thermosphere–Ionosphere-Energetics and Dynamics (TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperatures is presented. 相似文献
8.
Towards developing a geoscientific approach to sustainable agricultural and rural development 总被引：3，自引：0，他引：3
Dhia Al Bakri 《Environmental Geology》2001,40(4-5):543-556
Conventional practices employed to achieve sustainable agricultural and rural development (SARD) tend to be subjective, focus
on effects rather than causes, and have little diagnostic or predictive value. Consequently, many of the management options
and solutions adopted to restore degraded natural resources are, often, economically unviable and environmentally unsustainable.
These shortcomings are believed to be caused, partly, by overlooking or insufficiently recognizing the role and importance
of geology to SARD. This paper demonstrates that geology is the most critical factor in the genesis of biophysical resources
and in determining sustainability of agricultural and rural development. A case study from Australia shows how geological
principles can be employed to obtain goals of ecological sustainability. A geologically-based model for cold temperate regions
is provided to assist resource users and managers in understanding and predicting the genetic influence of geology on the
inherent potential, constraint and resilience of the biophysical resources.
Received: 7 January 2000 · Accepted: 23 May 2000 相似文献
9.
A finite element model was developed in order to solve for both regional groundwater flow and conservative solute transport in porous medium. The model was applied to a 55-sq-km groundwater basin in the Ruehen region of Germany using a network of 1450 elements and 780 nodes. This model was used in simulating a contaminant plume done through injection. Similarly, the model was applied to a 4750-sq-km portion in the eastern Nile Delta aquifer in Egypt. The model was applied to this portion of the delta using a network of 543 elements and 310 nodes with the main objective of simulating the problem of salt water intrusion. 相似文献
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