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FISH ASSEMBLAGE RESPONSES TO DIFFERENT SECONDARY CHANNEL DESIGNS IN THE LOWER mississippi RIVER,U.S.A.:A TEMPLATE FOR RIVER RESTORATION

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水生生物学报 2018年第6期42卷 1089-1106页

作者： KAISER Joseph E. SMITH Shannon C.F. SCHRAMM Jr.,HAROLD L. EGGLETON Michael A. Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff1200 N.UniversityMail Slot 4912Pine BluffArkansas 71601U.S.A U.S.Geological Survey Mississippi Cooperative Fish and Wildlife Research UnitMississippi State University

The lower mississippi River(LMR) has been heavily modified for multiple human purposes such as navigation, flood control, and bank stabilization. However, the LMR simultaneously supports a diverse fish fauna that includes recreational and commercial fisheries. Due to river training and diversion structures constructed during the past 80 years, the historic characteristics of the LMR have been drastically altered and have likely influenced fishes and fisheries in the system. One common restoration measure used throughout the LMR has been to "notch" wing-dike structures that close secondary(side) river channels. Dike notching allows year-round flows through secondary channels, which enhances habitat diversity and promotes biological productivity at the ecosystem scale. Although notching is presumed good for LMR fishes and other biota, few studies have examined its effects on fish assemblages. In this study, fish assemblages were sampled at seven LMR secondary channels spanning from river kilometer(rkm) 628(Louisiana-mississippi, U.S.A.) upstream to rkm 1504(Missouri-Kentucky, U.S.A.). Four secondary channels were termed "permanent"(i.e.,with notched dikes) while three secondary channels were termed "temporary"(i.e., without notched dikes).Fishes were sampled by boat-mounted electrofishing conducted during falling and low stages from1995—1997. Fish assemblages differed between permanent and temporary secondary channels, and varied somewhat between falling and low stages. Gizzard shad(Dorosoma cepedianum), threadfin shad(D. petenense), and white bass(Morone chrysops) demonstrated consistent preferences for low-current conditions associated with temporary secondary channels. Conversely, blue catfish(Ictalurus furcatus), flathead catfish(Pylodictis olivaris), and freshwater drum(Aplodinotus grunniens) were more associated with permanent secondary channels. Future restoration strategies in the LMR should consider dike notching and resultant maintenance of permanent seconda

关键词： mississippi River Secondary channels Dikes Fish assemblages River restoration River rehabilitation

ASIAN CARP EXPANSION IN THE mississippi RIVER:FOCUSING ON THE LEADING EDGE OF THE INVASION FRONT

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水生生物学报 2018年第6期42卷 1075-1080页

作者： TRIPP Sara PHELPS Quinton Big Rivers and Wetlands Field Station Missouri Department of Conservation3815 East Jackson BoulevardJacksonMissouri 63755USA West Virginia University Division of Forestry and Natural Resources307C Percival HallMorgantownWest Virginia 26505USA

Asian carp are expanding their range throughout the mississippi River; however, abundance is thought to be highest in reaches within close proximity to the Illinois River. In the mississippi River, Lock and Dam 19(L&D 19) at Keokuk, Iowa is the primary barrier to slow the expansion upstream. As Asian carp abundance increases below L&D 19, it is important to investigate potential means of control(i.e., reduction through harvest and barriers) that will prevent complete invasion of the mississippi River above L&D 19. Silver Carp and Bighead Carp were collected below L&D 19, a subsample were implanted with ultrasonic transmitters to evaluate passage through the lock chamber and the remainder were used to determine population dynamics at the leading edge of invasion. Although the dam portion of the structure poses a complete barrier to upstream expansion, we documented lock chamber passage demonstrating the lock chamber has the capability to provide passage upstream. Based on the results of the population assessment, in order to induce recruitment overfishing at this leading edge of invasion, Asian carp will need to be intensively harvested at 300 mm and larger. The combination of commercial fishing efforts and research investigating ways to prevent passage upstream must be employed.

关键词： mississippi River remainder

One-Dimensional Modeling of Sedimentation Impacts for the mississippi River at the West Bay Diversion

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Journal of Water Resource and Protection 2013年第9期5卷 16-29页

作者： Jeremy A. Sharp Ronald E. Heath Nathan D. Clifton USACE Engineering Research and Development Center Coastal and Hydraulics Lab Vicksburg USA

The Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) funded construction of the West Bay Sediment Diversion Project (WBSD) on the west bank of the mississippi River for the purpose of coastal restoration. A multi-tiered sediment study for the WBSD was conducted to determine impacts to the adjacent navigation channel and to the Pilottown Anchorage Area (PAA). One tier of the study is the implementation of HEC-6T, a one-dimensional (1-D) sediment model, to evaluate the regional impacts of the WBSD. The HEC-6T model results shows the long-term channel changes associated with the WBSD to be increasing shoaling in the adjacent areas on the order of 10% - 20%, as compared to the no WBSD condition. However, it is extremely difficult to isolate the impacts associated with a single diversion due to multiple diversions in the region. From a holistic vantage point, the 1-D model shows the necessity to examine, on a regional scale, the lower mississippi River as a single congruent system on a regional scale.

关键词： Diversion Dredging mississippi River Navigation Sediment

Irrigation Methods and Scheduling in the Delta Region of mississippi: Current Status and Strategies to Improve Irrigation Efficiency

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American Journal of Plant Sciences 2014年第20期5卷 2917-2928页

作者： Hirut Kebede Daniel K. Fisher Ruixiu Sui Krishna N. Reddy Crop Production Systems Research Unit USDA-ARS Stoneville MS USA

Even though annual rainfall is high in the Delta region of mississippi, only 30% occurs during the months in which the major crops are produced, making irrigation often necessary to meet crop water needs and to avoid risk of yield and profitability loss. Approximately, 65% of the farmland in this region is irrigated. The shallow mississippi River Valley Alluvial Aquifer is the major source of water for irrigation and for aquaculture in the predominant catfish industry. This groundwater is being heavily used as row-crop irrigation has increased tremendously. Water level in this aquifer has declined significantly over the past twenty five years, with overdraft of approximately 370 million cubic meters of water per year. Moreover, the common irrigation practices in the Delta re-gion of mississippi do not use water efficiently, further depleting the ground water and making ir-rigation more expensive to producers due to increasing energy prices. Irrigation experts in the re-gion have tested and verified various methods and tools that increase irrigation efficiency. This article presents a review of the current status of the irrigation practices in the Delta region of Mis-sissippi, and the improved methods and tools that are available to increase irrigation efficiency and to reduce energy costs for producers in the region as well as to stop the overdraft of the declining aquifer, ensuring its sustainable use.

关键词： The Delta Region of mississippi Irrigation Efficiency Irrigation Scheduling Furrow Irrigation Crop Water Use

Land Resource Areas and Spatial Analysis of Potential Location of Bioenergy Crops Production in mississippi

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Journal of Sustainable Bioenergy Systems 2021年第4期11卷 187-214页

作者： Yaw Adu Twumasi Edmund Chukwudi Merem John Bosco Namwamba Jacob Banafo Annan Tomas Ayala-Silva Abena Boatemaa Asare-Ansah Zhu Hua Ning Judith Oppong Priscilla Mawuena Loh Diana Botchway Frimpong Faustina Owusu Janeth Ernest Mjema Ronald Okwemba Olipa Simon Mwakimi Brilliant Mareme Petja Caroline Olufunke Akinrinwoye Joyce McClendon-Peralta Hermeshia Jonee Mosby Department of Urban Forestry and Natural Resources Southern University and A&M College Baton Rouge Louisiana USA Department of Urban and Regional Planning Jackson State University Jackson Mississippi USA USDA-ARS Tropical Agriculture Research Station 2200 P.A. Mayaguez Puerto Rico USA Institute of Resource Assessment University of Dares Salam Dares Salam Tanzania Water Research Commission (WRC) Private Bag X03 Gezina South Africa

mississippi State is renowned for its land resource areas (LRA) and production of bioenergy crops which generate both agricultural and economic benefits. Agricultural commodities play a key role in economic growth, therefore the ability to produce more would enhance development. This paper offers an analysis of the production of bioenergy crops in mississippi. Relative measures, time series graphs and descriptive statistics coupled with geographic information systems (GIS) mapping using ArcMap were employed to generate the outcome of this research. The outcome of the statistical analysis indicated that corn and soybeans were the most produced crops in Agricultural Districts 10 and 40. These districts produced more bioenergy crops than the other districts. GIS mapping results also showed that the potential area for bioenergy crops is in zone 131 of the mississippi Land Resource Area (MLRA). This zone has an absolute advantage in the production of these crops which includes the diversity of biomass production such as corn, cotton, soybeans, wheat, rice, barley, grain sorghum, canola, camelina, algae, hardwoods, and softwood. The paper recommends a constant GIS mapping and land management systems for each agricultural district in mississippi to enable researchers and farmers to determine the factors which contribute towards the increasing and decreasing trends in the production of the bioenergy crops.

关键词： Land Resource Areas GIS Bioenergy Crops Descriptive Statistics mississippi

The mississippi River in The Adventures of Huckleberry Finn

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海外英语 2014年第8X期 199-200页

作者：欧阳哈尔滨师范大学西语学院黑龙江哈尔滨150025

In The Adventures of Huckleberry Finn,The mississippi River is not just to provide a general background,but to constitute the center image of the *** gives"form"to the whole novel,all the adventures in the book begins with the river and ends with the *** paper talks about the important *** is a symbol of freedom and maternity,and it has deep meaning of life and regeneration,purification and *** symbols and senses of this river deepen the theme of the novel,and prop up its broad and profound metaphorical world.

关键词： The Adventures of Huckleberry Finn The mississippi

mississippi电厂远距离汽包水位指示器以它本身的优越性确立了其地位

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电站辅机 1988年第2期 46-47页

作者：沈家民 TOM ELLIOTT 华东电管局

在靠近Miss,Gulfport的mississippi电力公司的500MW Watson发电厂,一台汽包水位远距离传送的电子系统自从去年4月在一台2700psig(即～189.81公斤/厘米。)锅炉汽包上试验性安装以来正在正常地运行,

关键词：玻璃水位计 mississippi 水位指示器汽包锅筒电厂

国际摄影大展巡礼(之三) 美国Wilmington和mississippi　Valley国际摄影

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照相机 2002年第3期 26-27页

作者：邵大浪

美国是举办国际影展较多的国度,每年举办国际影展往往多达几十个.在这众多的国际影展中,除了美国摄影学会举办的PSA国际影展,Wilmington和mississippi Valley国际影展应是颇具特色和影响的.

关键词：国际摄影新闻摄影艺术摄影 Valley Wilmington mississippi 美国美利坚合众国北美洲

Convection–Diffusion Model for the Prediction of Anthropogenically-Initiated Wildfire Ignition

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International Journal of Disaster Risk Science 2014年第4期5卷 274-295页

作者： Ravi Sadasivuni Shanti Bhushan William H.Cooke Department of Geosciences Mississippi State UniversityStarkvilleMS 39759USA Center for Advance Vehicular Systems Mississippi State UniversityStarkvilleMS 39759USA

A spatial interaction model to predict anthropogenically-initiated accidental and incendiary wildfire ignition probability is developed using fluid flow analogies for human movement patterns. Urban areas with large populations are identified as the sites of global influencing factors, and are modeled as the gravity term. The transportation corridors are identified as local influencing factors, and are modeled using fluid flow analogy as diffusion and convection terms. The model is implemented in ArcGIS, and applied for the prediction of wildfire hazard distribution in southeastern mississippi. The model shows87 % correlation with historic data in the winter season,whereas the previously developed gravity model shows only 75 % correlation. The normalized error for convection–diffusion model predictions is about 5 % in the winter season, whereas the gravity model shows an error of 7 %.The proposed model is robust as it couples a multi-criteria behavioral pattern within a single dynamic equation to enhance predictive capability. At the same time, the proposed model is more costly than the gravity model as it requires evaluation of distance from intermodal transportation corridors, transportation corridor density, and traffic volume maps. Nonetheless, the model is developed in a modular fashion, such that either global or local terms can be neglected if required.

关键词： Anthropogenic-fire Convection–diffusion model Fire ignition potential mississippi Wildfire hazard