Skills and Expertise
Research Items (42)
- Jan 2019
This paper presents an analysis of the potential impact of existing and proposed natural and human activities on the behavior of existing watershed and suggests recommendations to effectively manage such activities to reduce the detrimental impacts on the watershed. The hydrologic behavior of the Piti-Asan watershed in Guam was analyzed through the field measurements of rainfall, stream level, stream flow, and river turbidity over the course of one year. Estimates of the erosion contribution by areas within the watershed and in particular, within 100-meter buffer zone around the major rivers were conducted based on the data collected via field instrumentation and using the geographic information system (GIS) based erosion model. Stage discharge curves were obtained for both watersheds from analyses of field hydrologic data. In addition, the areas contributing the most potential erosion and the major causes of soil erosion in the Piti-Asan watershed were identified. Finally, best management strategies of the watershed system to aid in maximizing the effectiveness and viability of future restoration efforts were suggested.
Question - Pls can give some input in this project ...?
I beleive the key to agricultural sustainability especially for small farmers and how to remain resiliant against climate chnage related issues is to make sure the soil carbon content remain high and above the treshhold level. Soil Carbon content is the key to agriculyural productivity as well as sustainability.
One good way to store the carbon in the soil and even sequester it is to apply 'biochar' as soil amendment. In our related studies we have found that land application of 'biochar' will enhance soil carbon dynamics at the same time increases the crop yield due to increasing cation exchange capacity of the soil.
I hope this answer help.
Talakhaya watershed in Rota is identified as a Coral Reef Management Priority site for CNMI (Commonwealth of Northern Mariana Islands). In 2010 federal and jurisdictional partners developed a Conservation Action Plan (CAP) for the Talakhaya Watershed. The goal of this initial Watershed Soil Loss Assessment therefore, was to assist in evaluating the re-vegetation objectives of ‘Mitigating Sediment Load’ in the Talakhaya watershed by making a thorough characterization of its main river systems. The objectives of this project were to reach those goals by measuring the hydrological parameters following the installation and the use of water meters, barometric level loggers, turbidity meters and rain gauges. The water flow as well as the turbidity level of each stream leading to the ocean from the Talakhaya Watershed was measured and sedimentation level was assessed accordingly. The results from the monitoring of the watershed conducted during the project timeline reported here show that all four rivers under study have statistically different stage-discharge curves. The river's relationship between time and turbidity also vary especially in the summer months of the first-year observations. Linear and convex polynomial relationships were sometimes observed in the different rainfall groupings for the four river systems, however relationships were often not significant. This-being-said, Quantile Regressions suggest that when data from all four river systems are combined for cases where there is some detectable rainfall, a maximum possible turbidity level can be defined. © 2018 International Research and Training Center on Erosion and Sedimentation and China Water and Power Press
- Dec 2017
- Soil Health and Intensification of Agroecosytems
This chapter covers net primary productivity (NPP) in intensified agroecosystems and its effects on soil carbon (C) sequestration, soil health, and carbon dioxide (CO2) emission. Although agricultural lands are a significant source of greenhouse gas (GHG) emissions, these lands also have a high potential for sequestering CO2 from the atmosphere via photosynthesis processes during crop growth and secure storage of C into the soil. Improving soil health by increasing soil C sequestration and the mitigation of GHG emissions into the atmosphere, entails high NPP and increases in soil C pools protected from microbial activities as well as oxidation processes (i.e., tillage). Assessing whether current or new intensified cropping systems result in net sink or source of CO2 and other GHG requires accurate measurements of C budgets. Thus, the focus of this chapter is to improve the knowledge base that is required to understand and implement agricultural practices that purposefully sequester soil C and reduce GHG emissions while simultaneously improving soil health.
Question - Hello great Professors, I have studied Hesperis flava which is already called Diplopilosa flava, I want to know whether it is biennial or perennial?
Dear Atena Eslami
greetings. I am afraid that your question is not within the area of my expertise. My area of work is soil and environmental sciences. people with expertise in plant taxonomy should be able to answer your question in detail.
Project - Soil carbon content dynamics as affected by the conservation practices and crop residue removal from the oxide rich, highly weathered, soils of southern Guam
We are working on two projects simultaneously under the aforementioned topic: 1) a field study, 2) a laboratory study. we are still collecting data from both projects.
Preface The 2nd 2016 International Conference on Agricultural and Biological Sciences (ABS 2016) was successfully held from July 23rd to July 26th in Shanghai, China, which is one of the largest urban areas in the world and the showpiece of the booming economy of mainland China. Agriculture is the cultivation and production of animals, plants, fungi, and other life forms for food, fiber, and biofuel, medicinal and other products used to sustain and enhance human life. Biological Sciences deals with the study of the many living organisms, which is closely related to agricultural sciences. Agriculture was the key development in the rise of sedentary human civilization. Promoting scientific and technological progress in the field of agricultural and biological sciences has become the consensus of all the countries in the world. Further challenges come from the climate change caused by global warming, environment pollutions, shortage of water resources and various animal and plant diseases pose new requirements for sustainable agricultural development. ABS conference series was held accordingly to provide a platform for scientists and researchers from all over the world to exchange their researches and new findings in those fields. Based on the success of ABS2015, ABS2016 attracts more than 100 participants from all over the world. With the theme of plant and animal sciences, the key focus of ABS2016 is on the areas of "Botanical Sciences", "Animal Sciences", "Soil and Environmental Science" and "Other fields in Agricultural Sciences". A special session named "Soil and environmental Science" also enriched the content of the Conference. More than 300 papers were submitted to ABS2016, and 82 submitted manuscripts have met the scope of IOP Conference Series on Earth and Environmental Sciences to form this special book. After pre-review on the originality and language, peer review process was arranged by the editorial committee. The editorial board was led by the Guest Editor Professor Mohammad Golabi and Associated Professor Peiyue Li, with support from following editors: Dr. Dionisios Gasparatos, Dr. Zisheng Xing, Dr. Ademir de Oliveira Ferreira, Dr. Elaheh Moussavi Kiassari, Dr. Khaled Ibrahimi, Dr. B. C. Dhananjaya, Hamed Kashi, Maria Regina Gusmao Valerio Menino and Dr. Ankit Garg. The 33 best manuscripts were selected after the pre-review and peer review, and those manuscripts provide some insights in the field of soil and environmental sciences. On behalf of the conference organizers, we would like to take this opportunity to express our sincere thanks to all the reviewers for their tremendous efforts and dedication to the Conference, to all the authors for their trust and contributions to the Conference, as well as all the colleagues from IOP publisher for their support and their endless efforts towards the publication of the proceedings for the Conference. The International Conference on Agricultural and Biological Sciences is convened annually where experts and scholars gather to exchange their newest ideas and experiences in this field, and we believe that with their earnest support and contributions, future ABS Conferences would scale new heights.
Question - What are the new global researches in the field of salinity / alkalinity management?
Dear Dr. Kumar Dubey
Greetings and thank you for your question regarding the soil salinity and alkalinity.
As you may know there are two conditions there that your question is referring to: 1) the soil salinity, and 2) soil alkalinity.
Here in Guam we do not have much problem with soil salinity however, as I am teaching about these conditions in my upper level soil courses, I can provide you with textbook answers on soil salinity.
On the other hand, we have a major problem with soil alkalinity here in Guam as the northern part of the island is all alkaline soil formed from the limestone parent material.
Among my soil research projects in northern Guam we have been trying to remedy the alkalinity problems there by employing various techniques and by using different amendments. Among the amendments that I have found to work the best is the application of compost material made from the organic waste including animal manure. You can use acidifying fertilizers such as ammonium sulfate or ammonium nitrate however, a good mature compost works better for neutralizing the alkalinity of the soil without having to deal with the problems associated with the commercial fertilizers. In addition, the compost will improve the physical, chemical and the biological properties of the soil for a sustainable agricultural system. I hope this will help however, please do not hesitate for asking me further questions if I can provide answer.
Eggplant (Solanum melongena L.) is a plant native to tropical regions of Southeast Asia. The water crisis and drought on the one hand and eggplant greenhouse crop development as one of the most popular fruit vegetables for people on the other hand, led to the need for more research on the use of saline water and water stress to optimize salinity level and their impact on eggplant evapotranspiration and encounter better yield and crop quality. The objective of the present study was to investigate the interactions of water salinity and hydroponic growth medium on qualitative and quantitative properties of eggplant and its water-use efficiency. The study used the factorial experiment based on completely randomized design with three replications of four levels of water salinity (electrical conductivity of 0.8 (control), 2.5, 5, and 7dSm−1) and three growth media (cocopeat, perlite, and a 50–50 mixture of the two by volume). Total yield, yield components, evapotranspiration, and water-use efficiency were determined during two growing periods, one each in 2012 and 2013. All of these indices decreased significantly as water salinity increased. Water with of 0.8dSm−1 produced an average eggplant yield of 2510g per plant in 2012 and 2600g in 2013. The highest yield was observed in cocopeat. Water with 7dSm−1 reduced yield to 906g per plant in 2012 and to 960g in 2013. Lowest yield was observed in perlite. The highest evapotranspiration values occurred in cocopeat at the lowest salinity in both years. Cocopeat and the cocopeat–perlite mixture were equally good substrates. The mixture significantly improved the quantitative and qualitative properties of eggplant yield.
Question - How soil microorganisms are related with the greenhouse gases (CH4, N2O, CO2) emission under agroecosystems?
soil microorganisms produce huge amount of Carbon dioxide, methane and other gases. when the soil surface is disturbed (e.g., tillage) the CO2 will emit into the atmosphere causing greenhouse effect thus global warming. Also, organic carbon that is stored in the soil will oxidize upon disturbances to the soil surface again adding another source of carbon dioxide emission to the atmosphere. amount of carbon dioxide emission from the soil is ten times more than all the carbon dioxide emission from fossil fuel burnings in a year.
Question - Is there anyone who can help me and give me information about the important parameters of salt mines in the treatment of respiratory diseases?
Dear Ms. Narjes Bay
your question is outside my expertise. However, I will try to talk to colleagues whom may know an answer.
The soils of southern Guam are formed from very deep; well-drained Saprolite derived from volcanic based tuff and tuff breccias. These soils suffer severe erosion as the result of rapid overland flow, wind and intensive rain events typical of southern Guam. An integrated approach to control the accelerated soil erosion was designed to include conservation tillage, crop rotation with leguminous plant, and residue management for soil surface cover. The objectives of this study are; 1) to evaluate the use of crop rotation and tillage management for increasing organic-matter content to improve the overall quality of these severely eroded soils, 2) to evaluate the effect of conservation practices on harvested yield and crop productivity of these eroded soils and, 3) to assess the effects of conservation techniques including no-tillage systems on water runoff and infiltration. This paper discusses the effect of conservation strategies and techniques on these severely eroded soils of southern Guam.
Question - What is the solution to the problem of the use of municipal waste compost, which increases heavy metal and EC in soil at long time?
I believe one remedy for lowering the EC and/or heavy metal content of the Municipal composting is to avoid composting the Municipal waste alone. Mixing the municipal waste with other organic material such as wood chips, animal manure and food waste could possibly lower the EC and even the heavy metal content by dilution and/or formation of complex compound. However, it all depends on the composting techniques. The aerobic composting via turning the compost with mechanical compost turner regularly could remedy some of the aforementioned problems.
- Jul 2013
One of the major problems with agricultural soils in the tropical region of the western Pacific islands is their low organic matter content, which results from rapid decomposition due to the hot and humid environment. Composted organic material is frequently applied on agricultural fields as an amendment to provide nutrients and also to increase the organic matter content and to improve the physical and chemical properties of soils. Our goal is to develop management strategies that can use available organic wastes on the farm for improving soil quality for better crop production while conserving resources and preserving environmental quality. The project described here is designed to improve soil fertility by addition of composted organic wastes and to assess the contribution of nitrogen and other essential nutrients to long-term soil fertility and crop productivity in the absence of synthetic fertilizers. In our pilot project, compost was produced from wood chips derived from grounded typhoon debris and animal manure, fish feed, and other organic wastes available at or in proximity of the farms. Mature compost was then applied to experimental plots of the eroded Cobbly soils of southern Guam at a rate of 0, 74, 148, or 296 metric tons per hectare. Maize planted on the plots showed great increases in both quality and yield, and the soil quality improved with each successive application of compost.
Five bacterial strains from genera Pseudomonas, Rhodococcus, Micrococcus and Bacillus isolated from petroleum-contaminated soils were selected for their capacity to grow in the presence of petroleum and some aromatic hydrocarbons. Their growth rates and biodegradation ability were investigated in mineral basic media supplemented with light oil, crude oil, aniline plus catechol, aniline, toluene and naphthalene. The results revealed the extents to which these strains could degrade different aromatic hydrocarbon that are toxic in the environment. The plasmid profiles of isolated bacteria were also determined and in some strains, biodegradation ability proved to be plasmid related.
- Jun 2008
Rainfall simulation and ponded inflltrometer methods were used to investigate the infiltration characteristics of no-till vs. conventional tillage farms. Seven pairs of no-till and conventional till farms under a corn-soybean rotation were selected on soils ranging from sandy loam to silty clay loams. The relative importance of surface residue and macroporosity (number of earthworms and middens) in both tillage systems was evaluated through the use of three different infiltration measurement techniques, and by the removal or addition of surface residue. The results of the ponded infiltration tests indicate that on the silt loam and silty clay loam soils, no-till farms had higher infiltration rates than those of conventional farms when earthworm activity and/or residue amount were higher in the no-till farms. On sandy loam soil, when earthworm activities were similar for both no-till and conventional farms, conventional farms had higher infiltration rates than the no-till farms. Under simulated rainfall, placing residue cover on the conventional plots generally increasedfinal infiltration rates for silt loam and silty clay loam soils. Furthermore, in the absence of plant residues, the no-till farms had equal and/or significantly higher infiltration rates than the corresponding conventional farms on the sites with silt loam and silty clay loam soils. As was the case with ponding infiltration, the terminal infiltration rate for the no-till farm was less with the rainfall simulator than for the conventional farm, at the site with sandy loam soil.
- Aug 2006
One of the major problems of agricultural soils in the tropical regions of the Pacific is the low organic matter content. Because of the hot and humid environment, the soil organic matter (SOM) is minimal due to rapid decomposition. Composted organic material is being applied on agricultural fields as an amendment to provide nutrients and enhance the organic matter content for improving the physical and chemical properties of the cultivated soils. In addition land application of composted material as a fertilizer source effectively disposes of wastes that otherwise are buried in landfills. In our soil program at the University of Guam, we are evaluating the use of organic material as an alternative to synthetic fertilizers. Its goal is to develop management strategies and use available resources for improving crop production while conserving resources and preserving environmental quality. Our case study project is designed to improve soil fertility status by using composted organic wastes and assessing how the nitrogen and other essential nutrients contribute to long-term soil fertility and crop productivity without application of synthetic fertilizers. In our pilot project, compost is produced from wood chips, grinded typhoon debris mixed with animal manure, fish feed, shredded paper and other organic wastes. Mature compost is then applied on the field at the rates of 0, 5, 10 and 20 t/ha as a soil amendment on the eroded cobbly soils of southern Guam. Corn is planted and monitored for growth performance and yield. The effect of land application of composted material on the SOM content and overall soil quality indices are being evaluated in this pilot study.
- May 2005
Severely eroded lands of southern Guam are referred to as BadLands. These are actively eroding areas of very deep, well–drained saprolite derived from tuff and tuff breccia. These badlands are exposed to overland flow, wind and rain causing sever erosion as the result of rapid runoff from the pitted, sloping sites void of vegetation. Through soil removal or sediment transport, erosion also alters the inherent physical and chemical properties of these soils. This alteration resulted in degradation, in turn affecting the environment as well as water quality in the down stream. The on-site damage from erosion is indeed a problem to environmental ecosystem of the island. Sediment lost due to erosion clogs rivers, lakes, and waterways. It reduces the water storage capacity of reservoirs and canals and increases flooding.The challenge facing soil and environmental scientists is to develop conservation and restoration strategies at the farm as well as at the watershed level that address crop production and natural resources protection needs, within a framework of increasing environmental and financial constraints. In our soil conservation program at the College of Natural and Applied Sciences of the University of Guam we have adopted integrated approaches to evaluate a variety of strategies, including the effect of conservation tillage and residue management, crop rotation with leguminous plants (sunnhemp) as green manure as well as the use of composted organic wastes as soil amendment for organic matter build up, all for soil rehabilitation and restoration of the badlands in southern Guam. In a companion study we are evaluating the effectiveness of Vetiver technology as a sediment trap to mitigate sediment transport in a typical watershed basin in southern Guam. This paper discusses the methodology as well as up to date data that shows the effect of Vetiver technology on sediment trapping at the watershed level.
Sedimentation as the result of runoff is the principle human-caused threat to the environment in general and the water quality in particular in the Pacific island of Guam. Runoff water is characterized by flash floods of high velocity but short duration. The rapid flow is attributed to low soil infiltration, a high proportion of rain converted to overland flow, and scanty or absent vegetation cover due to wildfires. In the areas where protective vegetation cover is lowest, the soil is subjected to the high shearing force by such an overland flow. Erosion damage is a serious problem to the environmental ecosystem of the island. Sediment lost to erosion clogs rivers, lakes, and waterways. Erosion and sedimentation loss are also a major source of water-quality problems in Guam. Sedimentation provides a vehicle for the transport of agricultural chemical residues into the canals, streams, rivers and eventually the near-shore ecosystems, where it damages coral reefs. The objective of the project reported here was to assess the sediment-loading rate to the near-shore coral reef originating from the upland watershed. The effectiveness of vetiver systems (VS) as a sediment trap and its effect on quality of the water leaving the upland watershed was evaluated. Four plots (22 x 1.5 m) were laid out on a uniformly sloped (12%) watershed for estimation of sedimentation rates. Each plot was equipped with 20 cm high flume wall that separated its surface from those of the other plots and their surroundings. Flumes are equipped with cone-shaped weirs that directed the runoff and sediments into a collecting tank beneath the weirs. In order to evaluate the effect of different soil surface management on erosion and quantify the sedimentation and turbidity of the runoff water from each plot, the following treatments were examined at this particular watershed: (i) Natural vegetation 'as it is' treatment, (ii) 'VS' treatment as a restoration technique, (iii) 'controlled burn' treatment, (iv) 'exposed surface-no-cover' treatment The above-mentioned treatments represent a wide range of conditions that are present in a typical watershed area in southern Guam.
- Jan 2005
Sedimentation as the result of runoff is the principle anthropogenic threat to environment in general and the water quality in particular in the Pacific Island of Guam. Runoff water is characterized by flash floods of high velocity but short duration. The rapid flow is attributed to low soil infiltration, a high proportion of rain converted to overland flow, and scanty or no vegetation cover due to wildfires. In the areas that protective vegetation cover is at its minimum, the soil is subjected to the high shearing force of such an overland flow. The on site damage from erosion is indeed a problem to environmental ecosystem of the island. Sediment lost due to erosion clogs rivers, lakes, and waterways. Erosion and sedimentation loss are a major source of water-quality problems in Guam. Sedimentation provides a vehicle for the transport of agricultural chemical residues into the canals, streams, rivers and eventually the near-shore coral reef ecosystems, damaging the coral reefs. The objective of this project is to make an assessment on the sediment-loading rate to the near-shore coral reef originated from the upland watershed. The effect of Vétiver grass as sediment trapping technique, as well as on water quality leaving the upland watershed is evaluated in this study. To achieve these objectives four plots (72ft × 5.5ft) are laid out on a uniformly sloped (12%) selected watershed to estimate the sedimentation rates. Each plot is equipped with 8-inch high flume wall in order to separate the individual plot's surface treatments from each other and surroundings. Flumes are equipped with a cone shape weirs, which will direct the runoff and sediments into a collecting tank beneath the weirs. In order to evaluate the effect of different soil surface management on erosion and quantify the sedimentation and turbidity of the runoff water from each plot, the following treatments are being examined at this particular watershed: a) Natural vegetation "As it is" treatment b) "Vetiver technology" treatment as a restoration technique c) "Controlled burned" treatment d) "Exposed surface - No-cover" treatment The above-mentioned treatments represent a wide range of conditions that are present in a typical watershed area in southern Guam.
- May 1988
Highly weathered soils of the Southeastern USA are poorly structured and may present special problems under continuous no-tillage production. Soil physical properties were examined in a long-term tillage experiment starting in its 10th year to determine if there were differences due to tillage. Fall/spring tillage treatments consisted of moldboard plow/moldboard plow (CT), moldboard plow/no-tillage (MT), and no-tillage/no-tillage (NT). Cone index measurements in NT exceeded 4 MPa at a depth of 0. 10 to 0. 20 m, indicating the presence of a compacted zone. We conclude that during short-term summer rainfall events, infiltration in conventionally tilled soil is controlled by surface crusting.
Leachate samples taken from the perimeter of the Ordot Landfill, in central Guam, were screened for priority pollutants listed under Section 307(a) of the Clean Water Act. Identified contaminants of concern were the fecal indicator bacteria, Enterococci and E. coli, inorganic nitrogen (N) and phosphorus (P), and several heavy metals. These contaminants were monitored in surface and subsurface waters down gradient of the landfill at monthly intervals for one year. Fecal indicator bacteria MPN counts in receiving surface waters dropped sharply within a few hundred meters downstream of leachate stream impaction points. However, values often exceeded the U.S. EPA rec- reational water quality standards all the way to the coast. Inorganic N was dominated by ammonium in the leachate stream and nitrate in the river. Occasional exceedences of the U.S. EPA surface water quality standard for nitrate (as NOx) were observed at all downstream sites. Inorganic (reactive) P was mostly undetectable in surface waters despite relatively high levels in the leachate stream. Likewise, heavy metal contaminants that were enriched in the leachate stream were mostly close to the limits of analytical detection in the river. Soil pore waters collected at various depths (0.61-1.83 m) ~100 m down gradient of the landfill were comparatively free of fecal indicator bacteria. Inorganic nitrogen levels, though enriched, were appreciably lower than those in the leachate stream, suggesting either denitrification, high assimilation by soil microbes, and/or high sorption by clays. Average P levels were also low suggesting removal by oxidic iron in surface layers. Neither inorganic N nor P concentrations varied significantly with soil depth. In contrast, mean pore water concentrations of alum- inum, cadmium, iron and zinc were generally more concentrated at the shallowest soil level. Inorganic N enrichment, and its effect on plant and algae growth in the lower reaches of the Lonfit River, was considered to be the most significant ecological impact of the landfill on the watershed. The transmission of human pathogens from the landfill into the river, in leachate streams and surface runoff, and the incorporation of potentially toxic metals into food chains ultimately leading to man, are likely the most important issues from a human health perspective.
Sedimentation as a result of runoff is the principal human-caused threat to the environment in general and to water quality in particular on the Pacific island of Guam. Runoff takes the form of flash floods of high velocity but short duration. The rapid flow is attributed to low soil infiltration, a high proportion of rain converted to overland flow, and scanty or absent vegetation cover due to wildfires. In the areas where protective vegetation cover is lowest, the soil is subjected to high shearing forces by such overland flow. Erosion damage is a serious problem to the environmental ecosystem of the island. Sediment lost to erosion clogs rivers, lakes, and waterways. Erosion and sedimentation loss are also a major source of water-quality problems in Guam. Sedimentation provides a vehicle for the transport of agricultural chemical residues into canals, streams, rivers, and eventually near-shore ecosystems, where it damages coral reefs. The objective of the project reported here was to assess the sediment-loading rate to the near-shore coral reef originating from the upland watershed. The effectiveness of Vetiver grass as a sediment trap and its effect on quality of the water leaving the upland watershed were evaluated. Four plots (each 72 5.5 ft.) were laid out on a uniformly sloped (12%) watershed for estimation of sedimentation rates. Each plot was equipped with an 8-inch-high flume wall that separated its surface from those of the other plots and their surroundings. Flumes were equipped with cone- shaped weirs that directed the runoff and sediments into a collecting tank beneath the weirs.
Agricultural development and improvement plays a major role in the overall economic development of Iran. The contribution from the agricultural sector towards the gross national product and supply of food and fiber is substantial. About 51 percent of Iran's 165 million hectares (ha) are made up of mountains, lakes, desert lands and towns, 11 percent are cultivated or fallow, 7 percent are forest, and 31 percent are marginal or rangeland. Only about fourth of the geographic area is potentially suitable for agricultural production, but in many areas rainfall is inadequate to permit cultivation without irrigation. Furthermore, the range of natural conditions creates differing agro-ecological zones and a wide variety of farming systems (UNDP- Irrigation Improvement Project, 1993). Iran has a history of irrigation extending back over several thousand years. In addition to major rivers such as 'Arras River', water for irrigation is supplied by "Ghanat", a way of conveying water from the mountain aquifers to villages as well as in some cities. In term of the water resources Iran has the highest per capita water availability in the Middle East ( 2150m 3 per capita against the average for the region of 950m 3 ). Resources are, however, not evenly spread, and only ten percent of the country has enough water for agriculture, and there is growing competition from municipal and industrial use around large towns (UNDP-Irrigation Improvement Project, 1993). In this respect the conservation and proper management of Soil and Water resources becomes crucial in the development and the sustainability of the agricultural production in Iran. Climatic conditions in the subproject areas vary from semi-arid in Behbahaan and Moghaan with average rainfalls of around 300mm, to sub-humid in Tajan, with an average annual rainfall of around 650mm. Annual evapotranspiration is 2,234mm in Behbahaan, 827mm in Moghaan, 1,184mm in Zarrineh Roud, and 838mm in Tajan (UNDP-Irrigation Improvement Project, 1993). Soils in these regions are of alluvial origin with textures that vary from silt loam to clay loam. Soils in Moghaan are mainly class I, those of Behbahaan are class II (UNDP-Irrigation Improvement Proj., 1993). In terms of fertility, Moghaan has the best soils while Behbahaan has relatively the least fertile soils (UNDP-Irrigation Improvement Proj., 1993). The agricultural development in Moghaan as well as in Behbahaan regions have brought into focus several problems such as over-exploitation of soil and water resources. Accelerated soil erosion due to lack of protection and excessive grazing by livestock in these areas have created alarming conditions. In this report the problem of soil erosion and the environmental impact of the erosion related to the irrigation projects in Moghaan and Behbahaan regions is discussed. Appropriate solution is suggested following each problem identification. 2 Historical background of subproject areas Due to its agricultural potential and capability, Moghaan has received special attention from the authorities prior to 1970 in which the government and private sector invested in the agricultural development in the region. They have invested considerable amounts of capital for the establishment of irrigation canals and irrigation systems. The "Arras River" diversion works in Moghaan were completed in 1970, with cost shared between the two riparian countries, ex-USSR and Iran. The net command area
Proceedings of the 1991 Georgia Water Resources Conference, March 19-20, 1991, Athens, Georgia. No-tillage and other conservation tillage systems are very effective in reducing erosion, in part because macropores consisting of cracks, root channels, and worm and insect burrows can speed the flow of water through the root zone. Macropores may also lead to faster movement of nitrates and pesticides through surface horizons under no-tillage, with the potential to contaminate shallow groundwater in Georgia. Our objectives were to compare macroporosity in conventional and no-tillage soils from Georgia, and to determine the effect of the initial rainfall on chemical leaching in these soils. Sponsored by U.S. Geological Survey, Georgia Department of Natural Resources, the University of Georgia, Georgia State University, and Georgia Institute of Technology. This book was published by the Institute of Natural Resources, The University of Georgia, Athens, Georgia 30602 with partial funding provided by the U.S. Department of the Interior, Geological Survey, through the Georgia Water Research Institute as authorized by the Water Resources Research Act of 1984 (P.L. 98242). The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of The University of Georgia or the U.S. Geological Survey or the conference sponsors.
Recent educational reports have suggested that the developments or key transferable skills, such as group working in the field, are a necessary outcome of higher education. A group working soil lab exercises were developed to evaluate the effectiveness of group field work by assigning formalized, individual group roles. Student responses and instructor observations suggested that there was considerable merit in this approach in terms of development of academic and transferable skills. It is suggested that this could serve as a precursor to a more formalized identification of group roles that would benefit both instructors and students alike in terms of successful field soil course delivery and meeting learning outcomes. Studies shown that field work is an essential element to learning soil science that provides a practical and stimulating supplement to classroom lectures. If facilitated appropriately, field work can provide an invaluable opportunity for students to develop many generic and subject-based skills, in addition to being a highly enjoyable experience. Field work can provide experiential learning in different environments, enabling students to compare and contrast knowledge acquired in the classroom with observations in the field. Field work also provides team building opportunities, produces a cohesive student body and develops instructor-students relationships. Despite the concerns regarding the quality of learning in the field, teaching/learning in the filed has been identified as essential for courses such as in Soil, Geography, and Environmental Sciences. The purpose of this article is to describe the use of group working in the field as a way of fostering active involvement of students in the natural resource classes that deal with natural settings. In this presentation some of the aspects of soil subject matter teaching and student learning in the field will be discussed and illustrated.