937 resultados para stream restoration
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CONTENTS: Approaches to understanding pond-dike systems in Asia: the POND-LIVE project approach, by Dave Little, Marc Verdegem and Roel Bosma. The contribution of fish ponds to nutrient cycling in integrated farming systems, by P.N. Muendo, J.J. Stoorvogel and Marc Verdegem. Improving the contribution of fishfarming to livelihoods in Northeast Thailand, by Chittra Arjinkit, Roel Bosma, Danai Turongrouang. Benefits of pond-dike systems in Bangladesh, by M.S. Kabir, M.A. Wahab and Marc Verdegem. Common carp increases rohu production in farmers ponds, by Mohammad Mustafizur Rahman, Md. Abdul Wahab and Marc C.J. Verdegem. Improving pond-dike farming systems in the Mekong delta, Vietnam; the Can Tho approach, by Dang Kieu Nhan, Le Thanh Duong, Le Thanh Phong, Roel H. Bosma and Marc C.J. Verdegem. Fuzzy pathways for farm development in Vietnam, by Roel H. Bosma, Le Thanh Phong, and Dang Kieu Nhan.
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Cambodia is one of the poorest countries in the world; much of its population live in rural areas and many live below the local poverty line. The management of common property aquatic resources is of over-riding importance to food security and sustainable rural development in Cambodia. The key groups of poor people who use aquatic resources as part of their diverse livelihoods portfolios are subsistence fishers, small-scale aquaculture practitioners and aquatic resources collectors. Subsistence fishers access mainly the rivers, lakes and inundated forests in Tonle Sap provinces, the lower Mekong and Bassac regions and the upper part of the Mekong. Small-scale aquaculture and/or the collection of aquatic resources are most important in provinces that are not rich in fisheries resources including Kompong Speu, Ratnakiri, Mondulkiri, Preah Vihear and Ortdar Meanchey. Freshwater capture fisheries probably contribute more to national food security and the national economy in Cambodia than in any other country in the world. (19 p.)
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228pp. (pdf contains 257 pages)
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The effects of the free-stream thermo-chemical state on the test model flow field in the high-enthalpy tunnel are studied numerically. The properties of the free-stream, which is in thermo-chemical non-equilibrium, are determined by calculating the nozzle flow field. A free-stream with total enthalpy equal to the real one in the tunnel while in thermo-chemical equilibrium is constructed artificially to simulate the natural atmosphere condition. The flow fields over the test models (blunt cone and Apollo command capsule model) under both the non-equilibrium and the virtual equilibrium free-stream conditions are calculated. By comparing the properties including pressure, temperature, species concentration and radiation distributions of these two types of flow fields, the effects of the non-equilibrium state of the free-stream in the high-enthalpy shock tunnel are analyzed.
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Health advisories are now posted in northern Florida Bay, adjacent to the Everglades, warning of high mercury concentrations in some species of gamefish. Highest concentrations of mercury in both forage fish and gamefish have been measured in the northeastern corner of Florida Bay, adjacent to the dominant freshwater inflows from the Everglades. Thirty percent of spotted seatrout (Cynoscion nebulosus Cuvier, 1830) analyzed exceeded Florida’s no consumption level of 1.5 μg g−1 mercury in this area. We hypothesized that freshwater draining the Everglades served as the major source of methylmercury entering the food web supporting gamefish. A lack of correlation between mercury concentrations and salinity did not support this hypothesis, although enhanced bioavailability of methylmercury is possible as freshwater is diluted with estuarine water. Stable isotopes of carbon, nitrogen, and sulfur were measured in fish to elucidate the shared pathways of methylmercury and nutrient elements through the food web. These data support a benthic source of both methylmercury and nutrient elements to gamefish within the eastern bay, as opposed to a dominant watershed source. Ecological characteristics of the eastern bay, including active redox cycling in near-surface sediments without excessive sulfide production are hypothesized to promote methylmercury formation and bioaccumulation in the benthos. Methylmercury may then accumulate in gamefish through a food web supported by benthic microalgae, detritus, pink shrimp (Farfantepenaeus duorarum Burkenroad, 1939), and other epibenthic feeders. Uncertainty remains as to the relative importance of watershed imports of methylmercury from the Everglades and in situ production in the bay, an uncertainty that needs resolution if the effects of Everglades restoration on mercury levels in fish are to be modeled and managed.
Receptivity to free-stream disturbance waves for blunt cone axial symmetry hypersonic boundary layer
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Based on high-order compact upwind scheme, a high-order shock-fitting finite difference scheme is studied to simulate the generation of boundary layer disturbance waves due to free-stream waves. Both steady and unsteady flow solutions of the receptivity problem are obtained by resolving the full Navier-Stokes equations. The interactions of bow-shock and free-stream disturbance are researched. Direct numerical simulation (DNS) of receptivity to free-stream disturbances for blunt cone hypersonic boundary layers is performed.
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Executive Summary: The Estuary Restoration Act of 2000 (ERA), Title I of the Estuaries and Clean Waters Act of 2000, was created to promote the restoration of habitats along the coast of the United States (including the US protectorates and the Great Lakes). The NOAA National Centers for Coastal Ocean Science was charged with the development of a guidance manual for monitoring plans under this Act. This guidance manual, titled Science-Based Restoration Monitoring of Coastal Habitats, is written in two volumes. It provides technical assistance, outlines necessary steps, and provides useful tools for the development and implementation of sound scientific monitoring of coastal restoration efforts. In addition, this manual offers a means to detect early warnings that the restoration is on track or not, to gauge how well a restoration site is functioning, to coordinate projects and efforts for consistent and successful restoration, and to evaluate the ecological health of specific coastal habitats both before and after project completion (Galatowitsch et al. 1998). The following habitats have been selected for discussion in this manual: water column, rock bottom, coral reefs, oyster reefs, soft bottom, kelp and other macroalgae, rocky shoreline, soft shoreline, submerged aquatic vegetation, marshes, mangrove swamps, deepwater swamps, and riverine forests. The classification of habitats used in this document is generally based on that of Cowardin et al. (1979) in their Classification of Wetlands and Deepwater Habitats of the United States, as called for in the ERA Estuary Habitat Restoration Strategy. This manual is not intended to be a restoration monitoring “cookbook” that provides templates of monitoring plans for specific habitats. The interdependence of a large number of site-specific factors causes habitat types to vary in physical and biological structure within and between regions and geographic locations (Kusler and Kentula 1990). Monitoring approaches used should be tailored to these differences. However, even with the diversity of habitats that may need to be restored and the extreme geographic range across which these habitats occur, there are consistent principles and approaches that form a common basis for effective monitoring. Volume One, titled A Framework for Monitoring Plans under the Estuaries and Clean Waters Act of 2000, begins with definitions and background information. Topics such as restoration, restoration monitoring, estuaries, and the role of socioeconomics in restoration are discussed. In addition, the habitats selected for discussion in this manual are briefly described. (PDF contains 116 pages)
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Healthy coastal habitats are not only important ecologically; they also support healthy coastal communities and improve the quality of people’s lives. Despite their many benefits and values, coastal habitats have been systematically modified, degraded, and destroyed throughout the United States and its protectorates beginning with European colonization in the 1600’s (Dahl 1990). As a result, many coastal habitats around the United States are in desperate need of restoration. The monitoring of restoration projects, the focus of this document, is necessary to ensure that restoration efforts are successful, to further the science, and to increase the efficiency of future restoration efforts.
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Cambodia is one of the poorest countries in the world; much of its population live in rural areas and many live below the local poverty line. The management of common property aquatic resources is of over-riding importance to food security and sustainable rural development in Cambodia. Aquatic resources are utilized principally by subsistence fishers and the landless, for whom aquatic resource use is an important livelihood activity. Subsistence fishers access mainly the rivers, lakes and inundated forests in Tonle Sap provinces, the lower Mekong and Bassac regions and the upper part of the Mekong. Freshwater capture fisheries probably contribute more to national food security and the national economy in Cambodia than in any other country in the world. (PDF contains 52 pages)
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This is the report of the “DoF/NACA-STREAM/FAO Workshop on Livelihoods Approaches and Analysis” that was conducted in Yangon, Union of Myanmar from 11-15 May 2004. The purpose of the workshop was to develop and document mechanisms for training in livelihoods approaches and analysis, and to build national capacity to conduct livelihoods studies. The workshop in Yangon was the first STREAM event in Myanmar, with colleagues coming to participate from Yangon and many Divisions and States throughout the country. The workshop in Yangon was the fourth in a series, the first of which was held in Iloilo City, Philippines, in November 2003, the second in Ranchi, India, in February 2004, and the third in Vientiane, Lao PDR in March 2004. A subsequent workshop will take place in Yunnan, China. The objectives of the workshop were to: Understand issues of interest to people whose livelihoods include aquatic resources management, especially those with limited resources Build “(national) livelihoods teams” to do livelihoods analyses and training, and share their experiences with communities and other stakeholders Share understandings of livelihoods approaches and analysis using participatory methods Review current NACA-STREAM livelihoods analysis documentation, adapt and supplement, towards the drafting of a Guide for Livelihoods Analysis Experience the use of participatory tools for livelihoods analysis Plan activities for carrying out livelihoods analyses, and Consider how to build capacity in monitoring and evaluation (M&E) and “significant change”. (Pdf contains 56 pages).
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The Scientific Forum on the Gulf of Mexico: The Islands in the Stream Concept took place in January 2008 in Sarasota, Florida. The purpose of the meeting was to bring together scientists and managers from around the Gulf of Mexico to discuss a range of topics on our knowledge of the Gulf of Mexico, from its geology to larger-scale connectivity to the Caribbean region, and their applications to the concept of a more integrated approach to area-based management. The forum included six panels of invited experts who spoke on the oceanographic and biological features in the Gulf of Mexico, including connections with Mexico and the Mesoamerican barrier reef system, and the legal and regulatory structure currently in place. The charge to the group was to share information, identify gaps in our knowledge, identify additional potential areas for protection, and discuss available science about connectivity and the potential value of establishing a marine protected area network in the Gulf of Mexico. (PDF has 108 pages.)
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This document presents the results of the first three monitoring events to track the recovery of a repaired coral reef injured by the M/V Elpis vessel grounding incident of November 11, 1989. This grounding occurred within the boundaries of what at the time was designated the Key Largo National Marine Sanctuary (NMS), now designated the Key Largo NMS Existing Management Area within the Florida Keys National Marine Sanctuary (FKNMS). Pursuant to the National Marine Sanctuaries Act (NMSA) 16 U.S.C. 1431 et seq., and the Florida Keys National Marine Sanctuary and Protection Act (FKNMSPA) of 1990, NOAA is the federal trustee for the natural and cultural resources of the FKNMS. Under Section 312 of the NMSA, NOAA has the authority to recover monetary damages for injury, destruction, or loss of Sanctuary resources, and to use the recovered monies to restore injured or lost sanctuary resources within the FKNMS. The restoration monitoring program tracks patterns of biological recovery, determines the success of restoration measures, and assesses the resiliency to environmental and anthropogenic disturbances of the site over time. To evaluate restoration success, reference habitats adjacent to the restoration site are concurrently monitored to compare the condition of restored reef areas with natural coral reef areas unimpacted by the vessel grounding. Restoration of the site was completed September 1995, and thus far three monitoring events have occurred; one in the summer of 2004, one in the summer of 2005, and the latest in the summer of 2007. The monitoring in 2004 was in the nature of a “pilot project,” or proof of concept. Only the quantitative results of the 2005 and 2007 monitoring are presented and discussed. Monitoring has consisted of assessment of the structural stability of limestone boulders used in the restoration and comparison of the coral communities on the boulders and reference areas. Corals are divided into Gorgonians, Milleporans, and Scleractinians. Coral densities at the Restored and Reference areas for the 2005 and 2007 events are compared, and it is shown that the densities of all taxa in the Restored area are greater by 2007, though not significantly so. For the Scleractinians, number and percentage of colonies by species, as well as several common biodiversity indices are provided. The greater biodiversity of the Restored area is evidenced. Also, size-class frequency distributions for Agaricia spp. (Scleractinia) are presented. These demonstrate the approaching convergence of the Restored and Reference areas in this regard. An inter-annual comparison of densities, within both areas, for all three Orders, is presented. The most noteworthy finding was the relative consistency across time for all taxa in each area. Finally, certain anomalies regarding species settlement patterns are presented. (PDF contains 48 pages.)
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This document presents the results of the first two monitoring events to track the recovery of a repaired coral reef injured by the M/V Wellwood vessel grounding incident of August 4, 1984. This grounding occurred within the boundaries of what at the time was designated the Key Largo National Marine Sanctuary (NMS), now designated the Key Largo NMS Existing Management Area within the Florida Keys National Marine Sanctuary (FKNMS). Pursuant to the National Marine Sanctuaries Act (NMSA) 16 U.S.C. 1431 et seq., and the Florida Keys National Marine Sanctuary and Protection Act (FKNMSPA) of 1990, NOAA is the federal trustee for the natural and cultural resources of the FKNMS. Under Section 312 of the NMSA, NOAA has the authority to recover monetary damages for injury, destruction, or loss of Sanctuary resources, and to use the recovered monies to restore injured or lost sanctuary resources within the FKNMS. The restoration monitoring program tracks patterns of biological recovery, determines the success of restoration measures, and assesses the resiliency to environmental and anthropogenic disturbances of the site over time. To evaluate restoration success, reference habitats adjacent to the restoration site are concurrently monitored to compare the condition of restored reef areas with “natural” coral reef areas unimpacted by the vessel grounding or other injury. Restoration of the site was completed on July 22, 2002, and thus far two monitoring events have occurred; one in the Fall of 2004, and one in the Summer/Fall of 2006. The monitoring has consisted of: assessment of the structural stability of restoration modules and comparison of the coral recruitment conditions of the modules and reference sites. Corals are divided into Gorgonians, Milleporans, and Scleractinians and (except where noted) recruits are defined as follows: Gorgonians—maximum size (height) 150 mm at first monitoring event, 270 mm at second; Milleporans—maximum size (height) 65 mm at first event, 125 mm at second; Scleractinians—maximum size (greatest diameter) 50 mm at second event (only one species was size-classed at first event, at smaller size). Recruit densities at the restored and reference areas for each event are compared, as are size-class frequency distributions. For the Scleractinians, number and percentage of recruits by species, as well as several common biodiversity indices are provided. Finally, a qualitative comparison of recruit substrate settlement preference is indicated. Generally, results indicate that restored areas are converging on reference areas, based on almost all parameters examined, with one noted exception. Further monitoring is planned and the trends are anticipated to continue; close attention will be paid to the indicated anomaly. (PDF contains 63 pages.)
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This document presents the results of the monitoring of a repaired coral reef injured by the M/V Connected vessel grounding incident of March 27, 2001. This grounding occurred in Florida state waters within the boundaries of the Florida Keys National Marine Sanctuary (FKNMS). The National Oceanic and Atmospheric Administration (NOAA) and the Board of Trustees of the Internal Improvement Trust Fund of the State of Florida, (“State of Florida” or “state”) are the co-trustees for the natural resources within the FKNMS and, thus, are responsible for mediating the restoration of the damaged marine resources and monitoring the outcome of the restoration actions. The restoration monitoring program tracks patterns of biological recovery, determines the success of restoration measures, and assesses the resiliency to environmental and anthropogenic disturbances of the site over time. The monitoring program at the Connected site was to have included an assessment of the structural stability of installed restoration modules and biological condition of reattached corals performed on the following schedule: immediately (i.e., baseline), 1, 3, and 6 years after restoration and following a catastrophic event. Restoration of this site was completed on July 20, 2001. Due to unavoidable delays in the settlement of the case, the “baseline” monitoring event for this site occurred in July 2004. The catastrophic monitoring event occurred on August 31, 2004, some 2 ½ weeks after the passage of Hurricane Charley which passed nearby, almost directly over the Dry Tortugas. In September 2005, the year one monitoring event occurred shortly after the passage of Hurricane Katrina, some 70 km to the NW. This report presents the results of all three monitoring events. (PDF contains 37 pages.)