Large Water Area Research Articles

Kinetic theory for aquatic animal distribution simulation

Identifying the underlying mechanisms that influence the spatial patterns in populations improves the forecasts of the alternative management strategies on the spatial dynamics of the populations, which are critical for assessing and managing the fisheries and improving the water resource management. This paper described a new approach of the numerical model for the prediction of the aquatic animal distribution in the flows. The model was developed based on the kinetic theory of gases, the mechanism of the aquatic animal movement and the flow hydrodynamic patterns. The model was validated using the available experimental data and an acceptable agreement was obtained. A comprehensive parameter study was then conducted to help understand the impact and the sensitivity of each parameter to the aquatic animal distribution. The promising results of the model reveal the prospect of applying this model to the reliable prediction of the aquatic animal distribution within a relatively large water area.

Improving optimization efficiency for the total pollutant load allocation in large two-dimensional water areas: Bohai Sea (China) case study

The total pollutant load allocation (TPLA) can be transformed into an optimization problem with regards to water quality constraints. The optimization calculation may become very time consuming when the number of water quality constraint equations is great. A Trial and Error Method (TEM) to remove the redundant points was first introduced through iterative calculations under structure and non-structure model grids. The TEM was applied for the TPLA in the Bohai Sea in China. The calculation time was reduced to about 2min under the condition that 103,433 model grids met the water quality standards. In the best case, the optimization efficiency was improved by 98.9%. The allocation results showed that approximately 90% of total nitrogen (TN) load should be reduced in the 56 pollution sources around the Bohai Sea; of these values, roughly 85% of the reduction could come from 10 pollution sources.

Challenge in Design and Construction of Submerged Floating Tunnel and State-of-art

Submerged Floating Tunnel (SFT) is a new type of transport structure. It is different from the general bridges and tunnels engineering, it has a significant advantage over conventional structures in crossing long, large and deep water areas. Hence, SFT has great potential for development of infrastructures in crossing straits. Aiming at features of SFT, this article discuses some challenges and problems, which are faced in design and construction of SFT, such as wave load determination, vortex-induced vibration, immigration and reduction of accidental load and situation, durability, innovational construction method, risk identification and control etc. The state-of-art and works done by Zhejiang University in the relative areas of SFT were introduced. The technological difficulties and corresponding solution were proposed. At last, the several key problems to be needed further research were proposed, so as to provide reference for the design, construction and project risk analysis of future SFT.

Recording seismoacoustic signals of a surface vessel with a two-coordinate strainmeter

Experimental data are analyzed, obtained during the recording of seismoacoustic signals with a two-coordinate laser strainmeter; the signals were generated by a surface vessel moving over the shelf and deep water. Based on analysis of the obtained data, we substantiate the prospect of applying shore-based laser strainmeters for the direction finding of vessels and the creation of monitoring systems for large water areas.

ASSESSING THE POTENTIAL OF WAVE ENERGY IN COASTAL WATERS OF CRIMEA PENINSULA

The present study reviews the previously used methods of wave energy evaluation and the results of these evalu tions for the marginal seas of the Russian Federation. Currently in the international practice the methods based on the processing of data reanalysis (wind speed) and the mathematical modeling (characteristics of the waves) are widely used for the wave energy evaluation. This approach allows energy for large water areas, individual points or local areas. For a selected point of the Black Sea the authors have conducted assessment of the wave energy usin mulating Waves Nearshore). The calculations used the wind field at a height of 10 m, derived from reanalysis NCEP / NCAR, with a time step of 6 hours, and the spatial resolution of 1,875 ° (i period from 1948 to 2010. For a specific date the map of significant wave heights and transport of energy in the Black Sea was created. A set of such maps or maps of tion can be used for identifying water area that are most relevant to accommodate the wave power plants

On numerical simulation of tsunami run‐up

AbstractThe improved adaptive grid method is presented for the numerical modelling of propagation of long surface waves in large water areas and their interaction with coasts. (© 2015 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Robust and fast scale-invariance feature transform match of large-size multispectral image based on keypoint classification

Scale-invariance feature transform (SIFT)–based algorithms often suffer from false matches of keypoints while being utilized to register multispectral remote sensing images. It is even worse for the registration of large water areas due to the lack of keypoints and high similarity of textures in such regions. To tackle these problems, a robust and fast SIFT match algorithm for multispectral image registration based on keypoint classification is proposed. This algorithm establishes match candidates through classifying the keypoints based on their scale spaces, where the keypoint matching is restricted on the same scale group. To obtain an accurate scale group, the ground sampling distance of images to be registered is normalized, while the initial scale ratio is estimated, relying upon the seed matches. Furthermore, for refining the match candidates and improving the matching robustness on water areas of the image, the keypoints are classified into keypoints of the land region (L-KPs) and keypoints of the water area (W-KPs). The L-KPs of the match candidates with sparse region on the two-dimensional representation of the location offset are excluded by the iterative bivariate histogram, and then the average location offset of the correct land matches is employed to exclude the outliers of the candidates associated with the W-KPs. Meanwhile, to reduce the computational cost, the images to be registered are divided into corresponding overlapped blocks, providing parallel computing and local rectification. Experiments were conducted on large-size remote sensing images at different resolutions and the results demonstrate the effectiveness of the proposed approach.

Editorial: Environmental phytoremediation: plants and microorganisms at work.

Editorial: Environmental phytoremediation: plants and microorganisms at work.

Rethinking the Mississippi River diversion for effective capture of riverine sediments

Abstract. Many river deltas in the world are vibrant economic regions, serving as transportation hubs, population centres, and commercial hotspots. However, today, many of these deltaic areas face a tremendous challenge with land loss due to a number of factors, such as reduced riverine sediment supply, coastal land erosion, subsidence, and sea level rise. The development of the Mississippi River Deltaic Plain (MRDP) in southeast Louisiana, USA, over the past century is a good example. Since 1932, approximately 4877 km2 of the coastal land of MRDP has become submerged. The lower Mississippi River main channel entering the Gulf of Mexico has become an isolated waterway with both sides losing land. In contrast, large open water areas in the Mississippi River’s distributary basin, the Atchafalaya River basin, have been silted up over the past century, and the river mouth has developed a prograding delta feature at its two outlets to the Gulf of Mexico. The retrospective analysis of this paper makes it clear that the main cause of the land loss in the MRDP is not the decline of riverine sediment, but the disconnection of the sediment sources from the natural flood plains. Future sediment management efforts in the MRDP should focus on restoring the natural connection of riverine sediment supplies with flood plains, rather than solely using channelized river diversion. This could be achieved through controlled overbank flooding (COF) and artificial floods in conjunction with the use of a hydrograph-based sediment availability assessment.

Pyrosequencing Revealed SAR116 Clade as Dominant dddP-Containing Bacteria in Oligotrophic NW Pacific Ocean

Dimethyl sulfide (DMS) is a climatically active gas released into the atmosphere from oceans. It is produced mainly by bacterial enzymatic cleavage of dimethylsulfoniopropionate (DMSP), and six DMSP lyases have been identified to date. To determine the biogeographical distribution of bacteria relevant to DMS production, we investigated the diversity of dddP—the most abundant DMS-producing gene—in the northwestern Pacific Ocean using newly developed primers and the pyrosequencing method. Consistent with previous studies, the major dddP-containing bacteria in coastal areas were those belonging to the Roseobacter clade. However, genotypes closely related to the SAR116 group were found to represent a large portion of dddP-containing bacteria in the surface waters of the oligotrophic ocean. The addition of DMSP to a culture of the SAR116 strain Candidatus Puniceispirillum marinum IMCC1322 resulted in the production of DMS and upregulated expression of the dddP gene. Considering the large area of oligotrophic water and the wide distribution of the SAR116 group in oceans worldwide, we propose that these bacteria may play an important role in oceanic DMS production and biogeochemical sulfur cycles, especially via bacteria-mediated DMSP degradation.

武汉与世界城市的水景形态学对比分析

在“武汉2049”长期发展战略规划提出将在2049年将武汉打造成为世界城市的背景下，关注到大部分的世界城市不仅拥有较高的经济水平，同时也提供一个优越的软环境，如城市水环境，为居民营造高质量的景观与居住环境。由此采用同时期遥感影像，从水景形态出发，将武汉与其他世界城市及一部分国内一二线城市进行比较，以四项重要的量化指标水体量、水斑块、水陆混合度、水岸线描述案例城市的水景特征，具体比较了8个指数包括不同类型水体量、水斑块均匀度、最大斑块比、分离度、熵值、水岸线长度、边缘密度等。研究结果显示：武汉是一个具有中等水量的城市、城市水斑块均衡、拥有相当长的水岸线、水陆混合度非常高；湖区是武汉高水陆混合度的主要原因；武汉拥有其他城市不能比肩的极长水岸线，水岸线是其最重要的城市特征。基于此总结提出了武汉在水景形态影响下的三个重点发展策略。 In November 2013, Wuhan “Year of 2049” Long-term Development Strategic Plan put forward to build Wuhan a world city. Under this background, we notice that most of the world cities not only have a higher economic level, but also have a good soft ambient just like waterscape to provide high-quality landscape and life for the citizens just like New York and Chicago. This article compares Wuhan to some typical world cities and some influential Chinese urban areas in term of the waterscape to emphasize the uniqueness and advantage. First we chose some case cities, then an evaluation system was built to analyze the water data extracted from the remote sensing image including four important quantitative indicators which were raised to describe the characteristic of the waterscape. Detailed indexes include water area, patches number, largest patch index, Split, entropy and total water line and edge density. The results indicate that Wuhan is a city with fairly large water area; its patch size is quite suitable for creating high quality living space and waterfront. The mixing degree of the land and water is extremely high and the longest waterline is a unique advantage of it. Then longest water line is the most important water character. In the comparison you can see Wuhan is the only one who owns so many lakes which several layers of living space are easy to form. Based on the research conclusion, three key development strategies were brought forward to participate in the development process of Wuhan.

Lagrangian analysis of the transport and processing of agricultural runoff in the lower Maumee River and Maumee Bay

Lagrangian analyses is used to evaluate the processing of nutrients and sediments during storm runoff events as water moved from the Maumee River loading station at Waterville, OH through the lower river, Maumee Bay and into Lake Erie's western basin. Chemical signatures of storm water at Waterville were used in combination with frequent collections of water at transects along the flow paths to evaluate processing. These signatures consisted of the contrasting chemographs of conservative parameters (chloride and sulfate), dissolved nutrients (dissolved reactive phosphorus (DRP) and nitrate) and particulate substances (suspended solids (SS) and particulate phosphorus (PP)). During low flow, sharp drops in concentrations of chloride and sulfate indicated that mixing zones between river water and bay/lake water occurred at the river mouth. During high flows, the location of the mixing zone between riverine and bay/lake water was indicated by the margin of storm-event sediment plumes, with larger storms extending further into the lake. Steep concentration gradients of DRP and nitrate between high storm water concentrations and low bay/lake water concentrations were also present at the plume margin. The large areas of storm water inside the plume margin contained high DRP and nitrate concentrations but relatively low SS and PP concentrations, due to SS and PP deposition along the flow paths. Because this deposition occurred in water with high DRP concentrations, little of the bioavailable PP was likely to have been released prior to deposition. This storm runoff water provides excellent media for algal growth.

Factors affecting the establishment success of the invasive piscivorous chub in small irrigation ditches in northern Kyushu, Japan

Habitat matching is an important factor for the establishment of alien fishes in recipient environments. The piscivorous chub, Opsariichthys uncirostris uncirostris, originally exclusively inhabited large water areas; however, the species has been introduced and established in small irrigation ditches on Kyushu Island. The evaluation of the habitat use of the piscivorous chub suggested that this alien fish uses the lentic-type irrigation ditches as a nursery ground and the lotic-type ditches as a spawning ground. This finding implies that the establishment of the piscivorous chub may require connectivity between lentic and lotic habitats.

Rigid Body Interaction for Large-Scale Real-Time Water Simulation

Simulating large amounts of water in real time is often achieved using heightfield methods. Allowing the water to interact with rigid bodies is essential for applications such as games, but traditional heightfield interaction methods concentrate on water-to-body effects by letting water flow through the bodies. We instead take an approach where the bodies block water. Our earlier method is improved in several ways, taking steps toward a single method to create both water-to-body and body-to-water effects. The new method is also visually compared to a traditional method by Thürey et al. A drawback of our method is that it has some grid aliasing artifacts that appear especially when the method is used for floating bodies. However, our method is demonstrated to work together with the Thürey method, which allows us to get the best of both worlds to simulate both floating and blocking bodies in a single scene. The method runs in real time for large areas of water even with a very limited GPU budget.

Monitoring the water area changes in Tetima-Kanglayka lakes region over the past four decades by remotely sensed data

车尔臣河下游自1989年改道以来,河道北边形成若干小湖,使台特玛湖-康拉克地区的水域格局发生了很大变化.干涸30多年的台特玛湖,随着自2000年起塔里木河下游应急生态输水工程的实施开始形成大片水域,且水域面积呈扩大趋势.2002年车尔臣河改道结束后康拉克地区的湖泊格局基本形成,而台特玛湖地区的水域则继续大幅变化.本文在1972-2012年102期遥感影像及其相关辅助数据基础上进行各项定量分析,详细描述台特玛湖-康拉克地区的水域变化过程,总结变化趋势,试图找出变化主导因素.笔者认为台特玛湖-康拉克地区的湖泊水域景观格局变化自1970s-2000年主要受车尔臣河径流量年际变化的控制,而21世纪以来则主要受塔里木河下游应急生态输水工程措施的影响.;From starting of diversions of lower reaches of Qarqan River, in 1989, there has been a lot of small lakes in the north side of the new riverbed, drives fluctuated changes of water area patterns in Tetima-Kanglayka lakes region. Since Emergency Ecological Water Transfusion(EEWT) project in lower reaches of Tarim River started in 2000, there are large water area began to reappear and expand in old Tetima lake bed, where there was dried up over than 30 years since a water caused by construction of Dashkol Reservoir. The lakes are already in stable position in Kanglayka region, but there are still big changes of water area in Tetima lake region, when the river diversions are finished in autumn 2002. In this paper, the water area change process and its change trend in Tetima-Kanglayka lakes region was analyzed in high temporal resolution based on a serial, 102 times, remotely sensed imageries which acquired from 1972 to 2012. A further study carried on integrated the result with runoff and transformed water amount data to find out dominant drivers of the changes. We concluded that water area landscape pattern changes was caused by interannual changes of Qarqan River run-off during 1970s till 2000, and has been controlled by the EEWT project in the lower reaches of the Tarim River till the end of research period.

On the prospects of Ultra-High Energy Cosmic Rays detection by high altitude antennas

Radio emission from Ultra-High Energy Cosmic Rays (UHECR) showers detected after specular reflection off the Antarctic ice surface has been recently demonstrated by the ANITA balloon-borne experiment. An antenna observing a large area of ice or water from a mountaintop, a balloon or a satellite may be competitive with more conventional techniques. We present an estimate of the exposure of a high altitude antenna, which provides insight on the prospects of this technique for UHECR detection. We find that a satellite antenna may reach a significantly larger exposure than existing UHECR observatories, but an experimental characterization of the radio reflected signal is required to establish the potential of this approach. A balloon-borne or a mountaintop antenna are found not to be competitive under any circumstances.

Heat Island Intensity in Seongseo, Daegu, South Korea - a Rural Suburb Containing Large Areas of Water

We examined urban heat island intensity in Seongseo, Dae gu, South Korea, where a large area of water is located within the suburb. We found a maximum urban heat island intensity of <TEX>$4.2^{\circ}C$</TEX>, which occurred around 7 PM in the summer season. Throughout the remainder of the year, we observed the largest heat island intensity levels during late night hours. In contrast, the winter season displayed the smallest values for heat island intensity. Our results conflicted with heat island intensity values for cities where suburbs did not contain water areas. Generally, cities with suburbs lacking water displayed the largest heat island intensity levels before sunrise in the winter season. We also observed negative urban heat island intensity levels at midday in all seasons except for the summer, which is also in contrast with studies examining suburbs lacking water areas. The heat island intensity value observed in this study (<TEX>$4.2^{\circ}C$</TEX>) was relatively large and fell between the averages for, Asia and Europe according to the relationship between urban population and heat island intensity.

The definition of urban stormwater tolerance threshold and its conceptual estimation: an example from Taiwan

The combination of climate change and urbanization is worsening urban flooding problems. Estimating the amount of rainfall that a city can tolerate without flooding is a fundamental task that is difficult to perform, although large amounts of resources are invested in urban flood control. The purpose of this study is to determine the tolerance threshold for stormwater in a city. Based on hydrometeorological characteristics and existing flood control facilities, the urban adaptive water capacity is analyzed to determine the critical rainfall loading. Different critical levels are defined. The low critical point represents the beginning of the water accumulation, while the intermediate and high critical points are defined as flooding with heights of 300 and 600 cm, respectively, in low-lying areas. This study adopts a simple conceptual method to illustrate the critical levels instead of applying complex hydrologic and hydraulic modeling, which require high-resolution spatial data. Three cities and one township in Taiwan are used as urban case studies and to verify the conceptual method. As the capital, Taipei City utilizes the highest flood control engineering technology of our case studies; it is also the site in which the lowest rainfall thresholds cause the accumulation of water to reach the intermediate and high critical points because its small ‘internal water areas’ increase the height of floods rapidly. Conversely, Taichung City has a large internal water area that can disperse accumulating waters without increasing flood height. The estimations of urban storm tolerance thresholds increase the understanding of the limitations of water protection facilities. These estimations may be combined with rainfall forecasts to increase early warning functions and provide a reference point for subsequent planning related to urban flood adaptation strategies.

Regional climate model: investigating the impacts of climate change on water availability in Nigeria.

Nigeria and the rest of African nations, despite the fact that they produce less than 4% of global greenhouse gas emissions, are considered the world’s most vulnerable regions with regard to the effects of climate change due to the fragility of their economies. However, it is still very difficult to assess the extent of such changes and the specific environmental impacts particularly on water supply and management over most Africa nations due to poor technological development and inadequate research work on this topical subject. In this paper, the third version of the ICTP regional climate model (RegCM3) and the observed surface data were used to investigate the evidence of climate change over Nigeria in the past years (1958 to 2007) with a view to determining the impacts of climate change on the water supply and management - one of the key areas where the climate change impact is adjudged most. The results of the study showed that in the recent past, the region had been witnessing higher temperatures, increased fluctuations in annual rainfall and increase in the salinity of soils and large areas of surface and underground water due to the increasing aridity of the climate; inadequate water supply and control installations as well as intensified marine pollution which are inimical to the health of the millions of Nigerians particularly along the coast of the Atlantic ocean. Key words: Climate change, impact, rainfall, temperature, water resources.

The penetrative mixing in the Laptev Sea coastal polynya pycnocline layer

The large recurrent areas of open water and/or thin ice (polynyas) producing cold brine-enriched waters off the fast-ice edge are evident in the Laptev Sea in winter time. A number of abrupt positively correlated transitions in temperature and salinity were recorded in the bottom and intermediate layers at a mooring station in the West New Siberian (WNS) polynya in February–March 2008. Being in the range of ∼0.5°C and ∼1.6psu these changes are induced by horizontal motions across the polynya and correspond to temperature and salinity horizontal gradients in the range of 0.3–1.0°C/10km and 1.4–3.5psu/10km, respectively. The events of distinct freshening and temperature decrease coincide with a northward current off the fast-ice edge, while southward currents brought saltier and warmer waters at intermediate depths. We suggest that the observed transitions are connected to altering pycnocline depths across the polynya. The source of relatively fresher waters at the intermediate depths in polynya is supposed to originate from penetrative mixing of surface low salinity waters to intermediate water depth. Several forcing processes that could be responsible for a penetrative mixing through the density interface in polynya are discussed. These are penetrative convection and shear-driven mixing that originates from two-layer water dynamics and/or baroclinic tidal motions. The heavily ridged seaward fast-ice edge could produce an additional source of turbulent mixing even through a shear-free density interface due to the increased roughness at the ice–water interface.