8 research outputs found

    Characteristics of Wetland Habitats and Waterfowl Populations in Oklahoma

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    Wildlife Ecolog

    Chapter 3 Wetland Design and Development

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    The history of efforts to design and develop wetland sites is extensive and rich, especially in the United States. This chapter provides an annotated view of the current state of wetland design and recommends an approach to future efforts using “Hydrogeomorphic Methodology.” Experience over the past century indicates that the most important part of wetland design and development is upfront work to: (1) determine what type of wetland historically occurred in, and is appropriate for a site; (2) understand and attempt to emulate the key ecological processes that created and sustained specific wetland types; (3) compare historical landscapes and wetland attributes with contemporary landscape and site conditions to understand remediating needs; and (4) determine management objectives and capabilities. The foundation for hydrogeomorphic assessments is analysis of historical and current information about geology and geomorphology, soils, topography and elevation, hydrological regimes, plant and animal communities, and physical anthropogenic features. The availability of this information is discussed and the sequence of actions used to prepare hydrogeomorphic matrices of potential historical vegetation communities and maps is provided as in application of information. Specific considerations for designing wetland infrastructure and restoring wetland vegetation are reviewed. An example of a wetland restoration project for the Duck Creek Conservation Area, Missouri is provided to demonstrate use of the hydrogeomorphic approach. We believe that future wetland design and development strategies should include the following actions: (1) wetland conservation must seek to achieve incremental gains at landscape-level scales; (2) the foundation of wetland design is determining the appropriate wetland type for the site being considered; (3) wetland designs should seek to restore and emulate historical form and process as completely as possible and to make systems as self-sustainable as possible; and (4) future design and development of wetlands must anticipate change related to climate, land uses, encroachments, and water availability and rights

    Chapter 3 Wetland Design and Development

    Get PDF
    The history of efforts to design and develop wetland sites is extensive and rich, especially in the United States. This chapter provides an annotated view of the current state of wetland design and recommends an approach to future efforts using “Hydrogeomorphic Methodology.” Experience over the past century indicates that the most important part of wetland design and development is upfront work to: (1) determine what type of wetland historically occurred in, and is appropriate for a site; (2) understand and attempt to emulate the key ecological processes that created and sustained specific wetland types; (3) compare historical landscapes and wetland attributes with contemporary landscape and site conditions to understand remediating needs; and (4) determine management objectives and capabilities. The foundation for hydrogeomorphic assessments is analysis of historical and current information about geology and geomorphology, soils, topography and elevation, hydrological regimes, plant and animal communities, and physical anthropogenic features. The availability of this information is discussed and the sequence of actions used to prepare hydrogeomorphic matrices of potential historical vegetation communities and maps is provided as in application of information. Specific considerations for designing wetland infrastructure and restoring wetland vegetation are reviewed. An example of a wetland restoration project for the Duck Creek Conservation Area, Missouri is provided to demonstrate use of the hydrogeomorphic approach. We believe that future wetland design and development strategies should include the following actions: (1) wetland conservation must seek to achieve incremental gains at landscape-level scales; (2) the foundation of wetland design is determining the appropriate wetland type for the site being considered; (3) wetland designs should seek to restore and emulate historical form and process as completely as possible and to make systems as self-sustainable as possible; and (4) future design and development of wetlands must anticipate change related to climate, land uses, encroachments, and water availability and rights

    13.1.3. Life History Strategies and Habitat Needs of the Northern Pintail

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    The northern pintail (hereafter pintail) is a common dabbling duck distributed throughout the Northern Hemisphere. Since 1955, the breeding population in North America has averaged 5,566,000, fluctuating between 10,124,000 (1956) and 2,471,000 (1989; Fig. 1). Pintail numbers are especially sensitive to habitat conditions that reflect the wet–dry cycle in the shortgrass prairie breeding areas of south-central Canada and the northern Great Plains of the United States. Populations of pintails also are affected by habitat conditions in key wintering areas, such as the Central Valley of California and Gulf Coast marshes. When wintering areas are fairly dry, birds have fewer resources and subsequent spring recruitment is lowered. Through the 1970’s, continental populations recovered when wetland conditions on breeding and wintering areas were good but fell when the prairies were dry and wetland conditions in wintering areas were poor. Unfortunately, habitat losses and degradation of prairie habitats caused by agricultural practices have coincided with prolonged drought since the early 1980’s. This combination of detrimental factors resulted in declining pintail numbers in the past decade. The long-term downward trend in pintail numbers has focused renewed attention on this species. This leaflet describes aspects of pintail life history that may be important for pintail management. It is not intended as a general reference on pintail biology. Readers interested in this should consult Bellrose (1980)

    Die Defektproteinämien und die Antikörpermangelsyndrome

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