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Semi-Automated Classification Of Gray Scale Aerial Photographs Using Geographic Object Based Image Analysis (Geobia) Technique, Ahmed Harb Rabia, Fabio Terribile Apr 2013

Semi-Automated Classification Of Gray Scale Aerial Photographs Using Geographic Object Based Image Analysis (Geobia) Technique, Ahmed Harb Rabia, Fabio Terribile

Ahmed Harb Rabia A.H. Rabia

Aerial photography is an important source of high resolution remotely sensed data. Before 1970, aerial photographs were the only remote sensing data source for land use and land cover classification. Using these old aerial photographs improve the final output of land use and land cover change detection. However, classic techniques of aerial photographs classification like manual interpretation or screen digitization require great experience, long processing time and vast effort. A new technique needs to be developed in order to reduce processing time and effort and to give better results. Geographic object based image analysis (GEOBIA) is a newly developed area …


Land Suitability Analysis For Policy Making Assistance: A Gis Based Land Suitability Comparison Between Surface And Drip Irrigation Systems, Ahmed Harb Rabia A.H. Rabia, H. Figueredo, T. L. Huong, B. A. A. Lopez,, H. W. Solomon, V. Alessandro Mar 2013

Land Suitability Analysis For Policy Making Assistance: A Gis Based Land Suitability Comparison Between Surface And Drip Irrigation Systems, Ahmed Harb Rabia A.H. Rabia, H. Figueredo, T. L. Huong, B. A. A. Lopez,, H. W. Solomon, V. Alessandro

Ahmed Harb Rabia A.H. Rabia

Land suitability assessment for irrigation is a very important tool not only in terms of agriculture development planning, but also to overcome the global problem of water scarcity. The aim of this study is to spatially evaluate land suitability of the study area, Kilte Awulaelo district in Ethiopia, for surface and drip irrigation methods based on GIS and remote sensing approaches. This work has been done as a part of the 29th Course Professional Master in Istituto Agronomico per l’Oltremare, Florence, Italy. Final suitability maps show the irregularity of suitability classes’ distribution over the study area. Results show that only …


Introducing A New Parametric Concept For Land Suitability Assessment, Ahmed Harb Rabia Mar 2013

Introducing A New Parametric Concept For Land Suitability Assessment, Ahmed Harb Rabia

Ahmed Harb Rabia A.H. Rabia

In an ecosystem, there is need to establish the quantity and quality of resources and their suitability for a certain range of land uses in order to assure its future productivity and sustainability of biodiversity. Parametric methods are widely used for land suitability evaluation. A new parametric concept “equation” of land suitability evaluation has been proposed to improve results of land suitability evaluation. Land suitability assessment for wheat production was conducted in order to compare results of the suggest method with classical parametric methods. Organic matter, CaCO3, pH, Slope, texture, drainage, depth, EC and altitude were recognized as factors affecting …


Planting Desert Sites, David A. Bainbridge Jan 2013

Planting Desert Sites, David A. Bainbridge

David A Bainbridge

Desert planting requires great care in preparing plants, handling plants and planting. With proper consideration of soil, climate and water availability plants can be established despite severe conditions of high temperatures, high winds, herbivory and lack of water.


Container Plants For Desert Restoration, David A. Bainbridge Jan 2013

Container Plants For Desert Restoration, David A. Bainbridge

David A Bainbridge

Container planting is essential for most desert restoration work because direct seeding is rarely successful. The containers best suited for desert planting are often taller (deeper) to facilitate root development. Fertilizer management, inoculation, irrigation and pruning can be used to maximize root growth with minimal shoot development.


Do We Really Need New Policies? A Study On Soil Sealing In Egypt, Ahmed Harb Rabia Oct 2012

Do We Really Need New Policies? A Study On Soil Sealing In Egypt, Ahmed Harb Rabia

Ahmed Harb Rabia A.H. Rabia

Egypt has the lowest area of agricultural land per individual in Africa. The agricultural land stands for a total of approximately 3.5 million ha which characterized about 3.5% of the total area of Egypt in 2007. The urban encroachment over arable productive agricultural land in Egypt is common and is called (urban desertification). Therefore, the annual loss of arable land to urbanization is 1.2%. This indicates a serious situation to the agricultural area. the Academy of Scientific Research & Technology (1994) has reported that during the period from 1978 to 1984, the annual expansion rates of the dwelling area ranged …


What's In Your Nitrogen Budget?, Robert Mikkelsen Aug 2012

What's In Your Nitrogen Budget?, Robert Mikkelsen

Robert Mikkelsen

No abstract provided.


Mapping Soil Erosion Risk Using Rusle, Gis And Remote Sensing Techniques, Ahmed Harb Rabia A.H. Rabia Jul 2012

Mapping Soil Erosion Risk Using Rusle, Gis And Remote Sensing Techniques, Ahmed Harb Rabia A.H. Rabia

Ahmed Harb Rabia A.H. Rabia

Soil erosion is one of the major causes of land degradation in arid and semi-arid areas like Ethiopia, including Tigray Highlands, which is highly affected by the risk of desertification. Tackling on-site effects of soil erosion requires understanding of the rates of soil loss as well as identification of the major controlling factors that accelerate or slow down these processes. The study aims to quantify the soil loss by erosion process and to specify the main factor affecting the Erosion development in the study area. The Study area was Kilte Awulaelo District which is situated in the eastern part of …


Modeling Of Soil Sealing By Urban Sprawl In Wukro, Ethiopia Using Remote Sensing And Gis Techniques, Ahmed Harb Rabia A.H. Rabia May 2012

Modeling Of Soil Sealing By Urban Sprawl In Wukro, Ethiopia Using Remote Sensing And Gis Techniques, Ahmed Harb Rabia A.H. Rabia

Ahmed Harb Rabia A.H. Rabia

Soil sealing is the covering of the soil surface with materials like concrete and stone, as a result of new buildings, roads, parking places but also other public and private space. Soil sealing by urban sprawl continues to increase all over the world where the area of urbanized land is increasing even more rapidly than the population. The degree of sealing is associated to the land use type and the density of population. Techniques of Remote Sensing and Geographical Information System (GIS) have been used widely to measure urban sprawl and to analyze the spatial features and unique mechanism of …


Gis Spatial Modeling For Land Degradation Assessment In Tigray, Ethiopia., Ahmed Harb Rabia A.H. Rabia May 2012

Gis Spatial Modeling For Land Degradation Assessment In Tigray, Ethiopia., Ahmed Harb Rabia A.H. Rabia

Ahmed Harb Rabia A.H. Rabia

Land degradation can be described as reduction in the present and prospective land quality and production, due to natural or anthropogenic dynamics. This phenomenon is one of the most important problems facing farmers and decision makers in several countries. This study aims to use GIS spatial modeling to quantify land (physically and chemically) degradation in the study area based on remotely sensed and field survey’s data. A GIS spatial model has been developed based on the LADA- FAO methodology to apply a land degradation assessment in the study area. Final land degradation map has been produced by combining the outputs …


Simulation Of Barley Grain Yield Using Artificial Neural Networks And Multiple Linear Regression Models, Omar Maghawri Ibrahim Hassan Jan 2012

Simulation Of Barley Grain Yield Using Artificial Neural Networks And Multiple Linear Regression Models, Omar Maghawri Ibrahim Hassan

Dr. Omar Maghawri Ibrahim

Developing models for simulation of barley grain yield is important for making early prediction. To simulate barley grain yield, a simple and advanced modeling techniques were used based on a field experiment that was conducted using 40 foreign barley genetic resources from 2007/08 to 2008/09 winter seasons at Kalubia Governorate, Egypt. The barley genotypes were imported from International Center for Agricultural Research in Dry Areas (ICARDA), Syria. Artificial neural network (ANN) and multiple linear regression (MLR) models were developed to simulate barley grain yield. The models were constructed using the first year of field data and validated with the second …


Constructing New Technology: The Crop Circle Gps Cart In Pictures, Gregory Keith Bartley Jr., Brandon J. Horvath Sep 2011

Constructing New Technology: The Crop Circle Gps Cart In Pictures, Gregory Keith Bartley Jr., Brandon J. Horvath

Gregory Keith Bartley Jr.

The crop circle spectrometer represents a breakthrough in unbiased sensor data. Unlike traditional passive sensors, it pulses light at a speed of 20,000 times per second. With this comes the ability of these filters to discern reflectance measurements from that of natural sunlight, allowing it to be used in environments of sun, shade, and even darkness. From these various reflectance values at different wavelengths, we get measurements of plant health known as vegetation indices. And different vegetation indices can tell us different things about the health of a plant. Couple this with the recent advances in GPS technology, we can …


Magnesium: An Overlooked Nutrient?, Robert Mikkelsen Jun 2011

Magnesium: An Overlooked Nutrient?, Robert Mikkelsen

Robert Mikkelsen

Magnesium nutrition of plants is frequently overlooked and shortages can adversely impact plant growth. Many essential functions require adequate Mg supplies... the most visible being its role in chlorophyll and photosynthesis... but less visible reactions are also dependent on an adequate supply of Mg. When needed, a variety of soluble and slowly soluble Mg sources are available to meet crop demands.


Literature Review - Pigments In Plant Health, Gregory Keith Bartley Jr. Apr 2011

Literature Review - Pigments In Plant Health, Gregory Keith Bartley Jr.

Gregory Keith Bartley Jr.

The solar radiation received at the Earth’s surface helps power the photochemical processes in photosynthesis. However, under sunlight, photosynthetic organisms are unavoidably exposed to potentially harmful levels of ultraviolet and visible light radiation. Consequently, plants have developed many mechanisms for the avoidance and dissipation of excess light energy. The growth of crops under increased solar irradiance during sub- and supra-optimal temperature conditions is an obstacle for increasing seasonal crop production in the transition zone. New methods for reducing the photoinhibitory effects of solar irradiation have been observed in the field of turfgrass. Through the application of pigment compounds to the …


Phenotypic, Pathogenic, Molecular And Phylogenetic Comparisons Of Bacteria Causing Aloe Rot From Three Countries, Yogeshwar Kumar, Jatindra Nath Samanta, Kunal Mandal, Narendra A. Gajbhiye Jan 2011

Phenotypic, Pathogenic, Molecular And Phylogenetic Comparisons Of Bacteria Causing Aloe Rot From Three Countries, Yogeshwar Kumar, Jatindra Nath Samanta, Kunal Mandal, Narendra A. Gajbhiye

Kunal Mandal

Bacterial soft rot disease of Aloe caused by heterogeneous genus Erwinia was reported from different parts of the world. In the recent past the genus underwent major taxonomic modifications. In the present study, four Aloe pathogenic bacterial strains isolated from India, The Netherlands and Yugoslavia have been compared. Different cultural, biochemical, physiological and pathological characters and protein/lipid profiles indicated that the strains belonged to two different genera, Pectobacterium and Dickeya. Species specific amplification of pel gene sequences also supported this. Phylogenetic analysis of rRNA gene (rDNA) sequence placed these Dickeya strains close to D. dieffenbachiae and D. zeae. On the …


Geologic Constraints On Rain-Fed Qocha Reservoir Agricultural Infrastructure,Northern Lake Titicaca Basin, Peru, Nathan Craig, Mark Aldenderfer, Catherine Rigsby, Paul Baker, Luis A. Flores Jan 2011

Geologic Constraints On Rain-Fed Qocha Reservoir Agricultural Infrastructure,Northern Lake Titicaca Basin, Peru, Nathan Craig, Mark Aldenderfer, Catherine Rigsby, Paul Baker, Luis A. Flores

Luis FLORES

This paper reports new data on qocha ponds from the Rio PucaraeAzángaro interfluvial zone, northern Lake Titicaca Basin, Peru. Qocha are a little known form of Andean agriculture that developed around 800e500 B.C. and remain in use today. Prior estimates suggested that in the study area, there were more than 25,000 qocha. While most Andean sunken beds are excavated to reach groundwater, qocha are rainfed ponds. How these rain-fed ponds functioned has been an open question, but one that is answered in part by research presented in this paper. We suggest that a thick impermeable stratum of clay that was …


Effects Of Fully Developed Vesicular Arbuscular Mycorrhizal Hyphae On Seed Germination Of Lolium Perenne, G Keith Bartley Jr, Richard J. Gualandi Jr, Robert M. Augé Apr 2010

Effects Of Fully Developed Vesicular Arbuscular Mycorrhizal Hyphae On Seed Germination Of Lolium Perenne, G Keith Bartley Jr, Richard J. Gualandi Jr, Robert M. Augé

Gregory Keith Bartley Jr.

Previous studies demonstrate that the inoculation of mycorrhizal spores in seeds can improve speed of germi- nation and establishment in grass seedlings. The universally positive effects of arbuscular mycorrhiza on plants suggest that fully developed mycorrhizal hyphae could potentially induce faster germination in seeds. This study presents data indicating that the inoculation of full grown hyphae in seeds of Lolium perenne inhibits speed of germination, independent of level of available soil nutrients. Daily measurements of seedling height between in- fected and non-infected plants at different starter fertilization rates in a sand profile showed that abuscular mycor- hiza influenced seeds emerged …


The Future Of Southern Agriculture, Gregory Keith Bartley Jr. Mar 2010

The Future Of Southern Agriculture, Gregory Keith Bartley Jr.

Gregory Keith Bartley Jr.

The increasing demand for the supply of energy in the south heavily impacts the allocation of water for use in agriculture. With such a high percentage of the south's freshwater going towards energy production, little can make its way into food, feed, and fiber. Because the need for this exponential energy production in the south is currently greater than its agricultural importance, southern farmers are left to endure heavy irrigation restrictions. The solution to this problem can manifest itself in one of two ways. Southern states can either implement strategies that can reduce plant water consumption without reducing yield, or …


Container Substrate Temperatures Affect Mineralization Of Composts, Helen T. Kraus, Robert Mikkelsen, Stuart L. Warren Jan 2000

Container Substrate Temperatures Affect Mineralization Of Composts, Helen T. Kraus, Robert Mikkelsen, Stuart L. Warren

Robert Mikkelsen

Traditional N mineralization studies have been conducted by soil scientists using soils and temperatures found in field production. As temperature, in part, governs the rate of mineralization, and container substrates reach much higher temperatures than do soils, the effect of these elevated temperatures on mineralization must be considered to begin to understand N mineralization in container substrates during production. The N mineralization patterns of three composts [turkey (Meleagris gallopavo) litter, yard waste, and municipal waste] were determined under three temperature regimes (45, 25, and 45/25 °C). More organic N was mineralized from composted turkey litter (CTL) than from municipal or …


Beneficial Use Of Swine By-Products: Opportunities For The Future, Robert Mikkelsen Jan 2000

Beneficial Use Of Swine By-Products: Opportunities For The Future, Robert Mikkelsen

Robert Mikkelsen

No abstract provided.


Soil Treatment For Restoration Projects, David A. Bainbridge Jan 1999

Soil Treatment For Restoration Projects, David A. Bainbridge

David A Bainbridge

Soil treatment is a critical step in restoration projects. When soil problems are ignored restoration projects fail. Erosion, compaction, limited infiltration and other problems can make a site very different from its historic function and structure. Treatment can be done with equipment or by hand and will greatly improve chances for success.


A Comparison Of Three Methods For Determining Root-Knot Nematode Infection Of Cotton Roots, Robert G. Mcbride, Robert Mikkelsen Jan 1999

A Comparison Of Three Methods For Determining Root-Knot Nematode Infection Of Cotton Roots, Robert G. Mcbride, Robert Mikkelsen

Robert Mikkelsen

Three methods for determining the extent of infection of cotton roots (Gossypium hirsutum L.) by root-knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, were compared. Root-knot nematode eggs were added to pots containing either sterilized soil or soil amended with rye, and cotton seedlings were planted. Cotton root systems were then assessed for infection/damage after 14 and 28 days of exposure. At the 14-day sampling, the roots were stained, using the lactophenol acid fuchsin method and the juvenile nematodes counted. At the 28-day samplings, the cotton roots were given a visual rating for nematode-induced root galling (0-100), and the galls …


Swine Waste Disposal Dilemma, Robert Mikkelsen Jan 1995

Swine Waste Disposal Dilemma, Robert Mikkelsen

Robert Mikkelsen

The swine industry has grown rapidly in North Carolina in the past decade, with the majority of the growth occurring in a few counties in the Coastal Plain region of the state. With this expansion has come the problem of swine waste disposal. Mr. Blevins, a local farmer in this region, has been raising swine since 1985. The swine waste on his farm is collected in an anaerobic lagoon and then irrigated onto a bermudagrass (Cynodon dactylon(L.) Pers.) pasture where cattle are fed using intensive rotational grazing techniques. A study of Mr. Blevins' farm revealed very high nitrate concentrations in …


Using Hydrophilic Polymers To Control Nutrient Release, Robert Mikkelsen Jan 1994

Using Hydrophilic Polymers To Control Nutrient Release, Robert Mikkelsen

Robert Mikkelsen

Using diverse technological approaches, many types of delivery devices have been used to supply plant nutrients at a controlled rate in the soil. One new approach is the use of hydrophilic polymers as carriers of plant nutrients. These polymers may be generally classified as 1) natural polymers derived from polysaccharides, 2) semi-synthetic polymers (primarily cellulose derivatives), and 3) synthetic polymers. By controlling the reaction conditions when forming the polymers, various degrees of cross-linking, anionic charge, and cationic charge can be added, thereby changing their effectiveness as fertilizer carriers. When fertilizer-containing solutions are mixed with hydrophilic polymers to form a "gel" …


Addition Of Gel-Forming Hydrophilic Polymers To Nitrogen Fertilizer Solutions, Robert Mikkelsen, A David Behel Jan 1993

Addition Of Gel-Forming Hydrophilic Polymers To Nitrogen Fertilizer Solutions, Robert Mikkelsen, A David Behel

Robert Mikkelsen

Environmental and economic concerns are causing a search for more effective fe rtilizer products and improved methods for managing existing fertilizers. This laboratory and greenhouse study was conducted to determine if the addition of gel-forming hydrophilic polymers to N fertilizer solutions could reduce N leaching loss and increase plant uptake of N. In the first experiment, a solution of urea ammonium nitrate (UAN, 32% N) was mixed with a variety of polymers at three concentrations, band applied to a sandy soil, and leached weekly for six weeks. Nitrogen leaching losses were reduced from 0 to 45% during the first four …


Controlled-Release Fertilizers To Increase Efficiency Of Nutrient Use And Minimize Environmental Degradation - A Review, Avi Shaviv, Robert Mikkelsen Jan 1993

Controlled-Release Fertilizers To Increase Efficiency Of Nutrient Use And Minimize Environmental Degradation - A Review, Avi Shaviv, Robert Mikkelsen

Robert Mikkelsen

Total world consumption of fertilizer N, P2 O5, and K2O in 1990 / 1991 was 78. 37. and 26 million tons per annum respectively, with a projected yearly increase of demand of about 2 to 3% . Trends in crop production (maize and wh eat) in the last four decades s how that N application rates increased about 15 times whereas its accumulation in grain increased only 3 to 4 times. At the same time nutrient recovery by crops remained relatively low (e .g. a bout 50% for N). This represents a potentially alarming situation from environmental, economic and resource …


The Effect Of Selenium On Sulfur Uptake By Barley And Rice, Robert Mikkelsen, Hongfu Wan Jan 1990

The Effect Of Selenium On Sulfur Uptake By Barley And Rice, Robert Mikkelsen, Hongfu Wan

Robert Mikkelsen

Because of their chemical and physical similarities, plant uptake of sulfur and selenium are closely related. Barley and rice were grown in greenhouse solution culture to examine the synergistic interactions between sulfate and selenate in plant uptake. In the presence of low concentrations of solution sulfate, shoot and root yields were decreased with additions of selenate. However, when sulfate was present in elevated concentrations, no selenium-induced yield reductions occurred. A synergistic interaction between sulfate and selenate caused an increase in the shoot sulfur concentrations with increasing concentrations of selenate at low sulfate solution concentrations. At elevated sulfate concentrations, no synergism …


Biuret In Urea Fertilizer, Robert Mikkelsen Jan 1990

Biuret In Urea Fertilizer, Robert Mikkelsen

Robert Mikkelsen

Urea has become the leading form of N fertilizer worldwide. Historically there has been concern about biuret formed during the manufacturing of urea fertilizer and the potential adverse effect of biuret on plant growth. In this paper, the fate of biuret in soils and its phytotoxicity is reviewed. Biuret is mineralized by many soil micoorganisms, but the process is much slower than for urea. Excessively high biuret concentrations can damage seedlings and, like urea, should not be placed in close proximity to germinating seeds. Crop tolerance to biuret varies according to the plant species, soil conditions, fertilizer placement, and method …


Phosphorus Fertilization Through Drip Irrigation, Robert Mikkelsen Jan 1989

Phosphorus Fertilization Through Drip Irrigation, Robert Mikkelsen

Robert Mikkelsen

Although P fertilization through drip irrigation systems has not been widely recommended, a review of currently available literature indicates this fertilizer application technique can offer many advantages when performed properly. Using drip irrigation to apply P fertilizer allows nutrient placement directly into the plant root zone during critical periods of nutrient demand. Less P fertilizer is generally required to achieve sufficient tissue P concentrations and equivalent yields when it is drip-applied than with other application methods. The distribution of drip-applied P in soil depends on soil properties, the source of P fertilizer, the rate of application, and the amount of …


Factors Affecting Selenium Accumulation By Agricultural Crops, Robert Mikkelsen, Albert L. Page, Frank T. Bingham Jan 1989

Factors Affecting Selenium Accumulation By Agricultural Crops, Robert Mikkelsen, Albert L. Page, Frank T. Bingham

Robert Mikkelsen

The accumulation of selenium by plants is of concern worldwide. Many regions grow crops that contain insufficient Se to meet animal nutritional requirements. In these locations with low Se, efforts have been made to increase tissue Se concentrations. Other areas have problems with excessive Se found in vegetation grown on seleniferous soils. Plant species vary in their ability to accumulate and tolerate Se. Selenium accumulator plants can accumulate extremely high Se concentrations (several thousand mg Se kg-1) when grown in seleniferous soils, whereas typical agricultural crops have a much lower Se tolerance (<50 mg Se kg>-1 ). It has been suggested that …