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Developing participatory models of watershed management in the Sugar Creek watershed (Ohio, USA)
Jason Shaw Parker,Richard Moore,Mark Weaver
Water Alternatives , 2009,
Abstract: The US Environmental Protection Agency (USEPA) has historically used an expert-driven approach to water and watershed management. In an effort to create regulatory limits for pollution-loading to streams in the USA, the USEPA is establishing limits to the daily loading of nutrients specific to each watershed, which will affect many communities in America. As a part of this process, the Ohio Environmental Protection Agency ranked the Sugar Creek Watershed as the second "most-impaired" watershed in the State of Ohio. This article addresses an alternative approach to watershed management and that emphasises a partnership of farmers and researchers, using community participation in the Sugar Creek to establish a time-frame with goals for water quality remediation. Of interest are the collaborative efforts of a team of farmers, researchers, and agents from multiple levels of government who established this participatory, rather than expert-driven, programme. This new approach created an innovative and adaptive model of non-point source pollution remediation, incorporating strategies to address farmer needs and household decision making, while accounting for local and regional farm structures. In addition, this model has been adapted for point source pollution remediation that creates collaboration among local farmers and a discharge-permitted business that involves nutrient trading.
Delineation of Potential Aquifer Zones from Geoelectric Soundings in KWA IBO River Watershed, Southeastern, Nigeria
M.U.Igboekwe,E.E. Okwueze,C.S. Okereke
Journal of Engineering and Applied Sciences , 2012,
Abstract: Geoelectric soundings have been carried out around the KWA IBO River watershed in Ikwuano and Umuahia, southeastern Nigeria. The geology of the area (Benin Formation) mainly consists of fine-medium-coarse grained sands. The data of eleven Schlumberger Vertical Electrical Soundings (VES), with a maximum AB/2=500 m, were analyzed using the resist software. The layer parameters thus obtained were used to calculate the Longitudinal Conductance (S) and the Transverse Resistance (T) distribution. Assuming the sandy aquifer is homogeneous and using the existing lithologs and pumping test data, data analysis was done to arrive at the Hydraulic Conductivity (K) and Transmissivity (Tr) distribution within the study area. Aquifer characterization of the area also showed that the resistivity range is between 400-350WM and aquifer thickness ranged between 68 m near Usaka Elegu and 325 m near Government College Umuahia. From the results obtained, aquifer hydraulic conductivity and transmissivity values in most parts of the Watershed were observed to be high. Average aquifer transmissivity was 1722 m2/day. In general sandy aquifer are known for their excellent groundwater potential due to the fact that the (K) values in such aquifer are high. The thick sandy aquifer exhibits high transmissivity values, which reflect the geological setting of typical sandy formation. Based on the above analysis potential aquifer zones have been identified for regional groundwater development.
The quaternary geological history of the Santa Catarina Southeastern Region (Brazil)
Anais da Academia Brasileira de Ciências , 2000, DOI: 10.1590/S0001-37652000000200011
Abstract: this paper supply subsidies for quaternary geological reconstruction of the southeastern state of santa catarina coast in brazil, being based on detailed geological mapping supported by a series of drilling data, which allowed to establish a stratigraphical hierarchy of the sedimentary deposits. among the mapped geological units stand out the extensive pleistocene shallow marine sandy sediments, which are commonly referred as a barrier island - lagoonal depositional system. a drilling campaign done in the domain permitted the sampling of material for 14c datings, and the obtained data confirmed some previously assumed ages. the sequence of events, that originated the holocene deposits, has been also reconstructed through drilling and 14c dating of the collected peat and shell samples. finally, the main characteristics of the most promising mineral prospect of the area, represented by voluminous calcareous shell deposits associated with holocene sediments, are also presented.
The quaternary geological history of the Santa Catarina Southeastern Region (Brazil)  [cached]
Anais da Academia Brasileira de Ciências , 2000,
Abstract: This paper supply subsidies for Quaternary geological reconstruction of the southeastern State of Santa Catarina coast in Brazil, being based on detailed geological mapping supported by a series of drilling data, which allowed to establish a stratigraphical hierarchy of the sedimentary deposits. Among the mapped geological units stand out the extensive Pleistocene shallow marine sandy sediments, which are commonly referred as a barrier island - lagoonal depositional system. A drilling campaign done in the domain permitted the sampling of material for 14C datings, and the obtained data confirmed some previously assumed ages. The sequence of events, that originated the Holocene deposits, has been also reconstructed through drilling and 14C dating of the collected peat and shell samples. Finally, the main characteristics of the most promising mineral prospect of the area, represented by voluminous calcareous shell deposits associated with Holocene sediments, are also presented.
Seed Bank Variation under Contrasting Site Quality Conditions in Mixed Oak Forests of Southeastern Ohio, USA  [PDF]
Christine J. Small,Brian C. McCarthy
International Journal of Forestry Research , 2010, DOI: 10.1155/2010/419482
Abstract: Seed bank composition was sampled in 192–2.5? quadrats, established in six regenerating clearcut ( 7 years) and six second-growth ( 125 years) mixed-oak forest stands in southeastern Ohio. Seed bank and aboveground composition diverged markedly (S?rensen's coefficient <10%), emphasizing the importance of fast-growing, early-successional germinants to early ecosystem recovery. Seed richness was significantly ( ) higher in clearcut stands, suggesting declining richness with stand age. Richness estimations 28%–60% higher than observed values demonstrated high seed bank heterogeneity, emphasizing the need for intensive sampling to assess temperate forest seed bank variation. Site quality (topographic aspect) strongly influenced seed bank composition, with greater importance of early-successional trees, thicket-forming shrubs, and nonnative species on mesic sites. Thus, forest seed banks are likely to play an important, site-dependent role in shaping competitive environments for commercially important timber species after harvesting and soil disturbance and have the potential for marked influence on postharvest forest development. 1. Introduction Management priorities in US National Forests have changed markedly over the past century, with current policy emphasizing management of forests as intact and functioning ecosystems [1, 2]. This ecosystem-based approach seeks to maintain forest productivity and production of goods and services, while protecting the physical, chemical, and biological processes associated with healthy ecosystem function (e.g., soil and water quality, nutrient cycling, and biological diversity) [2–4]. As disturbance is an essential component of forested ecosystems, influencing forest structure, function, and development, it follows that management practices based on a comprehensive understanding of forest disturbance and recovery processes should be the most successful in regenerating preharvest forest structure and composition and minimizing ecosystem impacts [1, 5]. Designing ecosystem-based management plans for large-scale, stand-initiating harvests are particularly challenging, as postharvest conditions may be quite different from similarly scaled natural disturbances [3, 6]. Like natural canopy-opening disturbance, stand-level harvest substantially alters site conditions (e.g., light availability, air and soil temperatures, soil moisture, nitrification, organic content), which in turn influences survival and reservoirs of plant species diversity in the postharvest community [7–9]. However, complete removal of overstory trees and
Examining Local Climate Variability in the Late Pennsylvanian Through Paleosols: An Example from the Lower Conemaugh Group of Southeastern Ohio, USA  [PDF]
Nicole D. Dzenowski,Daniel I. Hembree
Geosciences , 2012, DOI: 10.3390/geosciences2040260
Abstract: Three temporally close stratigraphic sections were excavated in Glenshaw Formation of Athens County, Ohio. The described units are Upper Pennsylvanian (Gzhelian, 305–302 Ma) and located in the distal portion of the Appalachian foreland basin. Mudstone units interpreted as paleosols were identified across all three sections. Detailed field and micromorphological studies lead to the recognition of two separate paleosols within the profile. The profile consists of a composite paleosol composed of two cumulative paleosols. The lower paleosol is interpreted as a calcic Vertisol which formed in a seasonally dry environment whereas the upper paleosol is interpreted as a gleyed Inceptisol which formed in a seasonally wet environment. The change in paleosol types is the result of increased precipitation which led to saturation of the soil and surface ponding. Pedogenic carbonate nodules are a common feature throughout the entire profile as are stress cutans. A coalesced carbonate horizon (Bk) was observed approximate 120 cm from the top of the profile in all three sections. This carbonate horizon formed in the Vertisol and later served as a barrier which limited the downward movement of surface water. This limited the gleization of the bottom portion of the overprinted Vertisol resulting in a diffuse boundary with the overlying Inceptisol and producing a composite paleosol.
Land Use/Cover and Naturalness Changes for Watershed Environmental Management (Southeastern Brazil)  [PDF]
R?mulo Theodoro Costa, Camila Francisco Gon?alves, Angela Terumi Fushita, José Eduardo dos Santos
Journal of Geoscience and Environment Protection (GEP) , 2017, DOI: 10.4236/gep.2017.511001
Abstract: Driving forces on the landscape require regional management and/or local actions, together with other external factors. To operationalize this approach, this paper carried out a comparative analysis of the naturalness dynamics of the Jacaré-Guaçu and Jacaré-Pepira watershed, based on land use/cover changes and a structural indicator of the landscape, over the 10-year (2004-2014), as support opportunities for improving its environmental planning and management. Land use/cover dynamics were obtained based on screen digitizing of LandSat imagery, using polygon manual digitalization. Naturalness scenarios of the watersheds, over the 10-year (2004-2014), were obtained based on Urbanity Indicator, which evaluates how much the natural landscapes are dominated by altered systems. The total area of watersheds showed a predominantly scenario, induced by anthropogenic agricultural and non-agricultural expansion areas, mainly by conversion of other land use/cover types in sugarcane cultivation. Despite the increase in natural vegetation areas, over the 10-year (2004-2014), Jacaré-Guaçu and Jacaré-Pepira watersheds are far from a sustainable condition. However Jacaré-Guaçu watershed presents a scenario of more committed naturalness due to the increase in Urbanity Index values ≥ 0.7. The historical process of land use occupation for agricultural production remains the main driving force of naturalness changes, occupying more than 70% of the total area of watersheds. These results have significant implications for fast urbanizing municipalities in providing key information about long term land use impact on the watershed structure and function, making it possible for policy makers, scientists and stakeholders to identify land uses which are hindered or enhanced under various scenarios of land use change over the time, and making it possible to explore the trade-offs between them to improve watershed management.
The Floras of Southern and Tropical Southeastern Yunnan Have Been Shaped by Divergent Geological Histories  [PDF]
Zhu Hua
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0064213
Abstract: The southern and tropical southeastern regions of the Yunnan Province in southwestern China have similar monsoonal climates and lowland tropical rain forest vegetations. The floras of both regions are dominated by tropical floristic elements (78.3% in southern Yunnan and 68.83% in southeastern Yunnan), and both belong to the Indo-Malaysian flora at the northern margin of tropical Asia. However, some temperate East Asian characteristic families are well represented in the flora of tropical southeastern Yunnan, while families characteristic of tropical Asia are well represented in the flora of southern Yunnan. Additionally, there are 14 mainly east Asian families in tropical southeastern Yunnan that are not found in southern Yunnan. Although the two regions share 80% of their genera, 237 genera are restricted to southern Yunnan, and 349 genera to tropical southeastern Yunnan. Furthermore, 57 genera with an East Asian distribution, 53 genera with a North temperate distribution, 22 genera endemic to China, and 17 genera with an East Asia and North America disjunct distribution are found only in tropical southeastern Yunnan. The flora of tropical southeastern Yunnan is more closely related to Eastern Asian flora, while the flora of southern Yunnan is more closely related to Indo-Malaysian flora. The divergence of the flora is well supported by the geological history of the region; the flora of tropical southeastern Yunnan was mainly derived from the South China Geoblock, while the southern Yunnan flora derived from the Shan-Thai Geoblock.
Aeromagnetic Data Modeling for Geological and Structural Mappings over the DJADOM-ETA Area, in the Southeastern Cameroon  [PDF]
Justine Yandjimain, Théophile Ndougsa-Mbarga, Marcelin Bikoro Bi-Alou, Arsène Meying
International Journal of Geosciences (IJG) , 2018, DOI: 10.4236/ijg.2018.96022
Abstract: The DJADOM-ETA area is in south-eastern of Cameroon, within the Congo Craton (CC) formations and composed of gneiss and amphibolite, migmatites and intrusive rocks. Few geophysical studies have been carried out over surrounding areas, but no investigation on the study area. The existence of aeromagnetic data covering the study area has motivated the application of a multiscale approach for tectonic features identification. The aim of this work is to interpret Aeromagnetic Data for Geological and Structural Mappings in the southeastern Cameroon. The GIS and GEOSOFT v8.4 softwares are used to treat data of Compagnie Minière du Cameroun getting in February 2012. The Tilt Angle method is used to delineate geological structures and to estimate the depth. The Euler’s Deconvolution method is used to estimate the specific depth of structural contacts. The presence of bifurcations, accompanied by virgations, leading to the occurrence of several faults. Principal lineaments are determined with the main direction being ESE-WNW and E-W for the minor lineaments. The study highlights two major faults: ESE-WNW and ENE-WSW, where the former dominates, what could be called the geological accident of ETA. The Euler’s Correlation and Tilt derivative contact map shows that most of the faults are vertical contacts. The geometrical description of this structure suggests an open synclinal transposed on vertical foliations: the major fault at the DJADOM axis is quasi-parallel to the Northern limit of the CC and parallel to the Sanaga Fault (SF) and the Central Cameroon Shear Zone (CCSZ). The features show a base strongly affected by tectonic which characterizes the transition between the zone from the CC and the belt from folds of the Pan-African. Also, the presence of the network characterizes the subsurface undulation in this study area: the intrusion of sandstone ochre quartz and schist of the Bek complex, the dolerite of the doleritic complex, and the silver micaschiste and ore quartzite in the base complex. On the TMI anomalies map, several places show high susceptibility contrasts, which is an indication of strong magnetization. Geological indicators point to inferred magnetite, dolerite and ochre schist quartzite which have a strong magnetization in this zone. The presence of weakly magnetized anomalies would be due to the migmatites of the base complex series. This study improved the knowledge of the subsurface structure of this area. It highlighted two major and minor faults. TMI anomalies map, in several places shows high susceptibility contrasts, which is an
Seed technology at The Ohio State University
Waters Jr., L.;
Scientia Agricola , 1998, DOI: 10.1590/S0103-90161998000500002
Abstract: the present paper shows the development of teaching, research and extension programs in seed technology at the ohio state university.
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