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At least 1,261 records · Page 70Linked to original sources
USGS2005

A landscape perspective for forest restoration

Forest managers throughout the West are anxiously seeking solutions to the problem of “large crown fires” - destructive blazes atypical of many forest types in the region. These wildfires have created a crisis mentality in management that has focused on rigid prescriptions for fuels reduction, rather than the restoration of diverse, resilient, and self-regulating forest ecosystems. Now, as we shape our responses to the threat of larger and more frequent crown fires, we are in danger of missing the forest for the trees.

Journal of Forestry↗
USGS2000

Would ecological landscape restoration make the Bandelier Wilderness more or less of a wilderness?

The purpose of this paper is to foster discussion on the basic issue of whether it is appropriate or not to intervene in designated wilderness areas that have been “trammeled by man” and, as a result, no longer retain their “primeval character and influence.” We explore this wilderness management dilemma (whether we can or should actively manage wilderness conditions to restore and protect wilderness and other values) by asking seven questions relating to a wilderness area that is no longer “natural.” (For the purposes of this discussion, “natural” is defined by words and phrases used in the 1964 Wilderness Act: “a community of life untrammeled by man”; “land retaining its primeval character and influence”; and or existing in an “unimpaired condition.”) Debate on this issue is not new, but is intensifying, since most wilderness areas in the continental United States are not pristine and ecosystem research has shown that conditions in many are deteriorating. To facilitate dialog on this wilderness management topic we focus on a case-study of a proposed large-scale project to restore piñon-juniper woodlands in the Bandelier Wilderness, New Mexico.

New Mexico↗
USGS1999

The partnership between park wild life management policy and landscape wild life management policy. How shall we then manage?

Resources management practices are changing in North America, not only based on greater understanding of the resources that are being managed, but also on some critical sociological relationship changes between human beings and between humans and nature. The entire way that humans look at the natural world and our own society is changing dramatically as we come to the end of the twentieth century. Managers are changing from making belief-based decisions to making informed knowledge-based decisions through better science programs. Society appears to increasingly be making a shift to a community mind-set, a mind-set of connectedness and interdependence, and away from strict individualism. Managers appear to be ready to embrace the concept of unity and wholeness; to understand that humans and nature are inextricably tied to each other’s wellbeing

George Wright Society Forum↗
USGS2001

Scientific and social landscapes: New frameworks and forums for water management and sustainability

The Two Decades of Water Law and Policy Reform conference examines the agenda for reforming and improving water law that has developed during the past two decades in the West, assesses what has (and has not) been accomplished by pursuing these reforms, and explores lessons and implications for future water law and policy. The papers and discussion provide analysis and lessons that can guide the new administration, Congress, federal agencies, state governments, and communities as they seek to find policy solutions to the challenges posed by the tremendous economic and demographic changes occurring in the West, in order to ensure the sustainability of the region’s unique environment. Specific sessions focus on reforms such as improving the scientific and technical basis for water management, water conservation and efficiency, protecting environmental values in meeting water demands, and creating new models of governance for water issues.

Conference Paper↗
USGS2017

Amphibians, pesticides, and the amphibian chytrid fungus in restored wetlands in agricultural landscapes

Information on interactions between pesticide exposure and disease prevalence in amphibian populations is limited, especially from field data. Exposure to certain herbicides and insecticides has the potential to decrease the immune response in frogs, which can potentially lead to increased abundance of Batrachochytrium dendrobatidis (Bd) zoospores on individuals and in the wetlands. In contrast, exposure to certain fungicides can decrease Bd abundance on frog skin. We examined the relationships between the abundance of Bd on the skin of individual Boreal Chorus Frogs (Pseudacris maculata) and the concentrations of pesticides in the water and in frog tissue at six agriculturally dominated wetlands in Iowa, USA. We collected frogs from each wetland, swabbed them for Bd, and analyzed their tissues for a suite of fungicides, herbicides, and insecticides. We collected surface water from the wetlands and we analyzed it for the same suite of pesticides. We observed no relationship between Bd zoospores on the skin of individual frogs and the concentrations of total pesticides, total herbicides/insecticides and total fungicides in frog tissue. Similarly, we observed no relationship between Bd zoospore abundance in water and the concentration of total pesticides or total herbicides in water. However, we observed a negative relationship between Bd zoospore abundance in water and neonicotinoid concentrations in surface water. Negative results are seldom reported but can be important contributors to a more complete understanding of the complex and potentially synergistic relationships between disease and pesticides. Data from field studies on these relationships are particularly scarce. As our laboratory understanding of these relationships expands, the need for field based, or applied, studies grow.

Iowa↗
USGS2018

Incorporating an approach to aid river and reservoir fisheries in an altered landscape

Reservoir construction for human-use services alters connected riverine flow patterns and influences fish production. We sampled two pelagic fishes from two rivers and two reservoirs and related seasonal and annual hydrology patterns to the recruitment and growth of each species. River and reservoir populations of Freshwater Drum Aplodinotus grunniens reached similar ages (32 and 31, respectively). Likewise, longevity of Gizzard Shad Dorosoma cepedianum between the two systems was also similar (7 and 8 years, respectively). However, both species grew larger in the rivers compared to reservoir residents. Recruitment of Freshwater Drum in reservoirs was negatively related to water retention time (r2=0.59) suggesting moving water through the reservoir was beneficial. Riverine recruitment of Freshwater Drum populations was negatively related to the annual number of flow reversals and positively related to prespawn discharge (r2 = 0.33). Unlike Freshwater Drum, there was no relationship between flow metrics and Gizzard Shad recruitment in reservoirs. However, recruitment of riverine Gizzard Shad was positively related to high flow pulses during the prespawn and spawning seasons (r2 = 0.48). The growth of both species in reservoirs was positively related to the number of days each year that water levels were above the conservation pool. Growth of Freshwater Drum was also negatively related to minimum reservoir summer water levels (r2 = 0.84). Growth of both Freshwater Drum and Gizzard Shad occupying lotic systems was positively related to May (r2 = 0.86) and July discharge (r2 = 0.84), respectively. In general, growth and recruitment of the reservoir populations was more related to annual water patterns, whereas riverine fishes responded more to seasonal flow patterns. Results of this study provide important information on the relationship between hydrology and pelagic fish production in both rivers and reservoirs. This information is useful if agencies are interested in developing holistic river-reservoir water-allocation plans.

Cooperator Science Series↗
USGS2002

Grassland bird communities and environmental health: The role of landscape features

Ecosystems throughout the world are imperiled by myriad anthropogenic factors. It is critical to develop tools for evaluating and monitoring the health or integrity of various ecosystems. Because of the broad scale of the problem, the urgency to address informational needs, and the limited financial resources committed to the problem, relatively inexpensive tools that encompass large areas are especially desirable. Remote sensing offers possibilities for such large-scale evaluation and monitoring. With aerial or satellite imagery, vast quantities of information from very large areas can be collected periodically.

Book chapter↗
USGS2019

Restoring a forest icon: Could returning the American chestnut remodel our wildlife landscape?

Mother Nature was not making it easy. It was February 18, 2009, and winds were gusting, sleet was falling, and temperatures were hovering around 40° F. Our crew of 9 which consisted of personnel from the USDA Forest Service Southern Research Station, the Cherokee National Forest, and The University of Tennessee’s Tree Improvement Program, was attempting to establish the first test planting of American chestnuts ( Castanea dentata ) bred for resistance to an exotic fungal pathogen, the chestnut blight ( Cryphonectria parasitica ). With each hole dug and seedlings tamped into the ground, our hope was that we were one step closer to restoring an important wildlife food to eastern hardwood forests.

Alabama, Connecticut, Delaware, Georgia, Illinois,↗