structure food webs and contaminant transport

... section defines and explains what food webs are and how they are viewed and analyzed, reviews information on trophic cascades in food webs, and considers top-down (consumercontrol) and bottom-up ... energy flows and species interactions in marine food webs and communities simply because all fished species are components of food webs and interact with other species through predation and competition ... Altered Food Webs, 35 Trophic Cascades, 41 Fishing Down and Through the Food Web, 45 Responding to Regime Shifts, 51 Recovery, Stability, and Multiple Stable States, 53 Major Findings and Conclusions...

Ngày tải lên: 17/02/2014, 19:20

... mathematical modeling, and numerical methods His present interests are in understanding and predicting the transport and fate of sediments and contaminants in surface and ground waters and the effects ... actions, the transport and fate of these sediments and associated contaminants must be understood and quantified More generally, the transport and fate of sediments and contaminants are basic ... a large area of tidal wetlands, the Meadowlands These wetlands serve as a storage area for water and contaminants during tidal cycles and storms Large variations in contaminant concentrations...

Ngày tải lên: 18/06/2014, 22:20

... 104/cm-s and the units of d and ws are cm and cm/s, respectively For d in µm and ws in µm/s, ws = 0.898 d2, or ws © 2009 by Taylor & Francis Group, LLC d2 (2.6) 32 Sediment and Contaminant Transport ... Sediment and Contaminant Transport in Surface Waters mineralogy and size of an inorganic particle tend to be related Large particles with a diameter greater than 62.5 µm are defined as sands and gravels ... flocs, and in the bottom sediments, where they initially form a relatively open and low-density structure that then deforms and compacts into increasingly larger and denser aggregates and clumps...

Ngày tải lên: 18/06/2014, 22:20

... 46 Sediment and Contaminant Transport in Surface Waters annular flume, the Shaker, and Sedflume) are described and compared; advantages and limitations of these as well as ... were retained and still impound water and sediments Because of the relatively large and rapid changes in the river bathymetry, the hydrodynamics and hence sediment properties and transport also ... properties are dynamic properties and depend on the spatial and time-dependent variations in the hydrodynamics and sediment transport and not just on the local water depth and average flow rate Because...

Ngày tải lên: 18/06/2014, 22:20

... collision process The VODL theory by Verwey and Overbeek (1948) and Darjagin and Landau has been developed that includes these forces and assists in understanding the cohesion of colliding particles ... efficient and suitable for use in calculating sediment and contaminant transport in surface waters 4.4.3 A VERY SIMPLE MODEL For exploratory purposes and as a first approximation in transport ... all sides, top, and bottom and kept away from windows and drafts Experiments were usually performed in the late afternoon and evening when the air temperature was about 20°C and relatively constant...

Ngày tải lên: 18/06/2014, 22:20

... Sediment and Contaminant Transport in Surface Waters models are described as a complement to the analyses of specific sediment and contaminant transport problems However, for a thorough understanding ... Taylor & Francis Group, LLC 196 Sediment and Contaminant Transport in Surface Waters maintenance, and decay, and therefore the time scales of interest were weeks and months rather than hours or even ... experimental and theoretical studies in the fields of aerodynamics and hydrodynamics (Daraghi, 1989; Graf and Yulistiyanto, 1998; Deng and Piquet, 1992; Richardson and Panchang, 1998; Ali and Karim,...

Ngày tải lên: 18/06/2014, 22:20

... Sediment and Contaminant Transport in Surface Waters Transport Rate (kg/m/s) 10–1 10–2 10–3 10–4 10–5 10–6 10 20 30 40 50 60 70 Time (hours) Total transport rate Bedload transport Suspended load transport ... treatment of suspended load and bedload, and bed armoring were included (Jones and Lick, 2000, 2001a) The hydrodynamics and sediment transport were approximated as two-dimensional and time dependent; ... experiment and model at the beginning of the experiment (Source: From Jones and Lick, 2001a.) © 2009 by Taylor & Francis Group, LLC 228 Sediment and Contaminant Transport in Surface Waters rates and...

Ngày tải lên: 18/06/2014, 22:20

... complex and requires considerable auxiliary data and computer time Because of this, a general calculation of the transport © 2009 by Taylor & Francis Group, LLC 298 Sediment and Contaminant Transport ... Francis Group, LLC 300 Sediment and Contaminant Transport in Surface Waters size and density distributions are not wide, and the variation in k is less than Because of this and because of our meager ... (7.16) o o and it follows that both Coc and Koc/Koc are functions of KocCw , as implied in Figures 7.9(a) and (b) For = 30, plots of Equations 7.15 and 7.16 are shown in Figures 7.9(a) and (b),...

Ngày tải lên: 18/06/2014, 22:20

... by Taylor & Francis Group, LLC 316 Sediment and Contaminant Transport in Surface Waters A simple and idealized problem of contaminant release and transport during environmental dredging is discussed ... Subscripts s and w denote suspended sediment and water, respectively; e and ne denote equilibrium and nonequilibrium, respectively; f, m, and c denote fine, medium, and coarse sediments; and avg © ... EROSION/DEPOSITION AND TRANSPORT Two HOC transport problems are discussed in this section: (1) the transport of PCBs in the Saginaw River, including the assumption of equilibrium partitioning; and (2) the transport...

Ngày tải lên: 18/06/2014, 22:20

Ngày tải lên: 07/03/2014, 02:20

... variables For lakes and reservoir study, contaminant transport and thermal stratification processes are important Hence contaminant c and water temperature T are chosen The contaminant transport equation ... guidance, understanding and support I will never forget Her wisdom, knowledge and commitment to the highest standards inspired and motivated me Her excellent guidance, discussions and patience helped ... Thesis Objectives and Outline 10 Mathematical model and Numerical methods vi 12 2.1 Laterally averaged model for lakes and reservoirs 13 2.2 Transport and thermal properties...

Ngày tải lên: 09/09/2015, 10:06

... environment, 2002) Food waste is the major source of decay, odor, and leachate in collection and transportation due to the high volatile solids (VS; 80~90%) and moisture content (75~85%) Food waste, ... 100 50 30 25 20 15 10 12000 Food waste composition 1.00 Food waste composition 0.80 Food waste composition 0.60 Food waste composition 0.40 Food waste composition 0.20 Food waste composition 0.00 ... contour lines against food waste composition and VS concentration CONCLUSIONS Food waste and sewage sludge at various VS concentration (from 0.5 to 5.0 %, w/v) and mixing ratio of food waste to sewage...

Ngày tải lên: 05/09/2013, 08:40

... controlled - 168 - MATERIALS AND METHODS Feedstock and seeding source Food waste collected from a school cafeteria, and paper waste comprised of toilet paper, newspaper, and copy paper were shredded ... standard temperature and pressure (STP), 0°C and 760 mmHg The contents of CH4, N2, and CO2 were determined by gas chromatography (GC; Gow Mac series 580) using a thermal conductivity detector and ... waste was 7:3 on a weight basis and a certain amount of water was added to adjust the TS concentration The TS concentration of food waste and paper waste was 20% and 99%, respectively Volatile...

Ngày tải lên: 05/09/2013, 10:15

... Exploring the Structure of Space and Time http://www.nap.edu/catalog/9680.html Gravitational Physics Exploring the Structure of Space and Time Committee on Gravitational Physics Board on Physics and Astronomy ... provide candid and critical comments that will assist the authors and the NRC in making the published report as sound as possible and to ensure that the report meets institutional standards for ... Exploring the Structure of Space and Time http://www.nap.edu/catalog/9680.html GRAVITATIONAL PHYSICS: EXPLORING THE STRUCTURE OF SPACE AND TIME When gravitational fields are weak and vary only...

Ngày tải lên: 12/02/2014, 16:20

... FLUID -STRUCTURE INTERACTIONS SLENDER STRUCTURES AND AXIAL FLOW VOLUME FLUID -STRUCTURE INTERACTIONS SLENDER STRUCTURES AND AXIAL FLOW VOLUME MICHAEL P PAIDOUSSIS ... velocity and pressure fields, V and p For fluid -structure interaction problems in which the forces induced by the fluid on the structure are the only concern, most of the information on V and p ... analytical modelling and interpretation of experimental observation far easier than in systems involving bluff bodies and cross-flow; it permits a better understanding of the physics and makes a more...

Ngày tải lên: 13/02/2014, 16:20

... Food Security and World Food Summit Plan of Action, World Food Summit Rome, Italy FAO (1999a) ‘Agriculture, Trade and Food Security: Issues and Options in WTO negotiations,’ Report and papers of ... with widespread poverty and malnutrition, large national food deficits and increasingly higher dependence on food imports and other concessionary aid However, the problem of food insecurity varies ... morbidity and mortality, which both worsened and was exacerbated by the food crisis, creating a dual tragedy Commercial and subsistence agriculture are particularly susceptible to the pandemic and...

Ngày tải lên: 15/02/2014, 19:20

... insights into food- webs structure and ecosystem functioning (Hillebrand and Shurins chapter) The structure and functioning of ecological systems is determined not only by local constraints and interactions, ... Introduction Andrea Belgrano PART I Structure and function Biosimplicity via stoichiometry: the evolution of food- web structure and processes James J Elser and Dag O Hessen Spatial structure and dynamics ... traditional food- web snapshot analyses to take into account space and time when assessing changes in food- web structure and species composition By comparing food webs from different environments and...

Ngày tải lên: 17/02/2014, 19:20

... Consumer trust in food production and consumer satisfaction from food products Horizontal lines Sustainable Food Production Systems and Packaging Systems Traceability and Food safety Food chain Raw ... consumer trust and consumer satisfaction, is determining all other issues and therefore requires a proper approach to understand the consumers perception of food and food processing This demands the ... needs and demands related to food safety and health were analysed, including questions of behavioural science and communication Secondly a priority setting within the large landscape of food safety...

Ngày tải lên: 22/02/2014, 05:20

... article is to review and evaluate the available epidemiological evidence about the association between dietary exposure to preformed nitrosamine and related food intake and gastric and oesophageal ... type and quality of dietary assessment method, number and type of food items; results including the most fully adjusted odds ratio or rate ratios and 95% confidence intervals for the highest and ... two groups: nitrosamines and nitrites; food sources of endogenous (red meat) and exogenous (processed meat, beer, pickled and dried vegetables, smoked fish or meat, salted and dried fish or meat)...

Ngày tải lên: 06/03/2014, 02:21