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Information is presented on establishment, survival, and growth of seven selected browse species in a ponderosa pine forest over a 10-year period. Methods of establishment included hand seeding and planting bare-root and containerized stock. Success of different methods differed with shrub species.
The decline of martens in Minnesota is reviewed and a recent increase documented. Adjacent and partially overlapping home ranges of 4.3 to 19.9 sq km were determined by telemetry for a female and three males. Habitat use is described. If current trapping and timber management practices persist, martens should continue to increase.
The purpose of the research was to evaluate the efficacy of point count surveys in bottomland hardwood forests. The specific objectives were to determine: (1) whether the recommended distance measures for point count circular plots are useful in bottomland hardwood forests, (2) the optimum duration for each point count, (3) the optimum number of points to sample at each locality, (4) the optimum number of counts at each point during a season, and (5) the minimum sample size to accommodate the variation in bird species distribution and relative abundance throughout the lower MAV.
This report presents updated information on a 1981 Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco var. menziesii ) plantation spacing trial at 33 years from planting. Stand statistics at the most recent measurement were compared for initial spacing of 1 through 6 meters and associated relative densities. There was no clear relationship of spacing to top height. Diameter, live crown ratio, and percent survival increased with spacing; basal area and relative density decreased with increase in spacing. Volume in trees ≥ 4 cm diameter was greatest at 2 m spacing, while utilizable volume (trees ≥20 cm dbh) was greatest at 4 m spacing. Live crown ratio decreased and total crown projectional area increased with increasing relative density indices. Total crown projectional area was more closely related to relative density than to basal area.
Six species of sand lance ( Ammodytes ) in temperate and boreal regions are currently recognized. Sand lance can occupy a wide range of environmental conditions, but all appear to be dormant predominantly in winter, and one species is in summer also. They lack a swim bladder and spend much of their time buried in specific substrates. Copepods are the primary food. Spawning usually occurs in fall or winter (although some species also spawn in spring), eggs are demersal, and larvae may hatch at times of low food abundance. Sand lance usually occur in schools and are regarded as a relatively high-quality forage fish. Sand lance constitute a major prey for at least some populations of over 100 species of consumer, including 40 species of birds, 12 species of marine mammals, 45 species of fishes, and some invertebrates. Variation in the availability of sand lance (and other forage fishes) can have major effects on the breeding success and survival of their predators. Commercial fishing and other pressures on sand lance populations potentially have ramifying effects on many species of wildlife. The bibliography contains over 1,700 references on the family Ammodytidae, with an emphasis on the genus Ammodytes . Keywords are provided for each reference and have been further organized into taxonomic, geographic, subject, and predator indexes.
Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus mykiss). Whether stocked trout use tributaries in this system for spawning is unknown. Furthermore, an inventory of the resident fish communities in these tributaries is lacking. To address these gaps, we surveyed 10 tributaries, from intermittent through third order, for fishes during presumed spawning periods of rainbow trout; we used backpack electrofishing in February and April 2015 and 2016 to determine the composition of the fish assemblages and whether trout were present. Stocked adult trout were found in three tributaries in 2015; wild juvenile rainbow trout were found in Bee Branch in 2015 and in an intermittent tributary of Spillway Creek, just above the “Cold Hole,” in 2016. Fish assemblages were dominated by highland stonerollers (Campostoma spadiceum) in larger, wider systems and by orangebelly darters (Etheostoma radiosum) in smaller, narrower streams. These data fill an information gap in our understanding of small streams in the Ouachita Mountains, and they demonstrate that some streams are suitable for rainbow trout reproduction.
Passive acoustic monitoring is a promising method for monitoring rare and nocturnal species, and for tracking changes in forest wildlife biodiversity. We conducted simulations to compare and evaluate various passive acoustic sampling designs effectiveness for monitoring spotted owl ( Strix occidentalis caurina ) population trends. We found that each design was effective for detecting a decline (or stability) in spotted own populations within 10 years with even a moderate amount of sampling. There are however, important considerations and tradeoffs among the various design options. Often, estimated changes in use of the landscape were biased with a consistently lower magnitude of change compared to simulated changes in the population. Although this method has challenges, passive acoustic monitoring can be used to effectively monitor northern spotted owls in the Pacific Northwest.
The field of urban stream ecology has evolved rapidly in the last 3 decades, and it now includes natural scientists from numerous disciplines working with social scientists, landscape planners and designers, and land and water managers to address complex, socioecological problems that have manifested in urban landscapes. Over the last decade, stream ecologists have met 3 times at the Symposium on Urbanization and Stream Ecology (SUSE) to discuss current research, identify knowledge gaps, and promote future research collaborations. The papers in this special series on urbanization and stream ecology include both primary research studies and conceptual synthesis papers spurred from discussions at SUSE in May 2014. The themes of the meeting are reflected in the papers in this series emphasizing global differences in mechanisms and responses of stream ecosystems to urbanization and management solutions in diverse urban streams. Our hope is that this series will encourage continued interdisciplinary and collaborative research to increase the global understanding of urban stream ecology toward stream protection and restoration in urban landscapes.
This collection of 30 short papers is the third published chapter of "Geological Survey Research 1972." The papers report on scientific and economic results of current work by members of the Geologic and Water Resources Divisions of the U.S. Geological Survey. Chapter A, to be published later in the year, will present a summary of significant results of work done in fiscal year 1972, together with lists of investigations in progress, cooperating agencies, and Geological Survey offices. "Geological Survey Research 1972" is the thirteenth and last volume of the annual series Geological Survey Research. The short-papers chapters (B, C, and D) will be replaced in 197 3 by the "Journal of Research of the U.S. Geological Survey," and the summary chapter (A) will be published as a separate professional paper. The twelve volumes already published are listed below, with their series designations.
This collection of 59 short papers on subjects in the fields of geology, hydrology, topography, and related sciences is one of a, series to be relea~ed during the year as chapters of Professional Paper 450. The papers in this chapter report on the scientific and economic· results of current work by members of the Geologic, Topographic, and 'Vater Resources Division of the United States Geological Survey. Some of the pa.pers annom1ce new discoveries or present observations on problems of limited scope; other papers draw conclusions from more extensive or continuing investigations that in large part will be discussed in greater detail in reports to be published in the future.
The devastating consequences of the 2004 Indian Ocean and 2011 Tohoku-oki tsunamis have led to increased research into many different aspects of the tsunami phenomenon. In this paper, we review research related to the observed complexity and uncertainty associated with tsunami generation, propagation, and occurrence described and analyzed using a variety of stochastic models. In each case, tsunamis generated by earthquakes are primarily considered. Stochastic models are developed from the physical theories that govern tsunami evolution combined with empirical models fitted to seismic and tsunami observations, as well as tsunami catalogs. These stochastic models are key to providing probabilistic forecasts and hazard assessments for tsunamis. The stochastic methods described here are similar to those described for earthquakes (Vere-Jones, 2013) and volcanoes (Bebbington, 2013) in this Encyclopedia.
This paper provides an overview of some of the more important developments in fluid-inclusion research and applications in recent years, including fluid-inclusion petrography, PVTX studies, and analytical techniques. In fluid-inclusion petrography, the introduction of the concept of 'fluid-inclusion assemblage' has been a major advance. In PVTX studies, the use of synthetic fluid inclusions and hydrothermal diamond-anvil cells has greatly contributed to the characterization of the phase behaviour of geologically relevant fluid systems. Various analytical methods are being developed and refined rapidly, with the Laser-Raman and LA-ICP-MS techniques being particularly useful for volatile and solute analyses, respectively. Ore deposit research has been and will continue to be the main field of application of fluid inclusions. However, fluid inclusions have been increasingly applied to other fields of earth science, especially in petroleum geology and the study of magmatic and earth interior processes.
No abstract available.
Overview Cattail ( Typha ) is an iconic emergent wetland plant found worldwide. By producing an abundance of wind-dispersed seeds, cattail can colonize wetlands across great distances, and its rapid growth rate, large size, and aggressive expansion result in dense stands in a variety of aquatic ecosystems such as marshes, ponds, lakes, and riparian areas. Cattail can also quickly dominate disturbed areas with waterlogged soils such as roadside ditches, retention areas, and fringes of stormwater ponds. These dense stands impact local plant and animal life, biogeochemical cycling, and wetland hydrology, which in turn alter wetland functions. Over recent decades, the distribution and abundance of cattail in North America has increased as a result of human disturbances to natural water cycles and increased nutrient loads. In addition, highly competitive nonnative and hybrid taxa have worsened the rapid spread of cattail. Because cattail invasion and expansion often change wetlands in undesirable ways, wetland managers often respond with widespread management efforts, though these efforts may have short-lived or weak effects. Notwithstanding the negative impacts, cattail provides beneficial ecosystem services including the reduction of pollution through bioremediation and the production of biofuel material. Despite the widespread distribution and invasive characteristics of cattail, a comprehensive review and synthesis of past and current research on cattail was lacking. To address this gap, a diverse team of researchers produced a paper that details the spread and management of cattail throughout North America, summarizing 4 decades of research from more than 650 references (Bansal and others, 2019). This fact sheet highlights the primary topics covered in the paper.
Ground motion selection and scaling comprises undoubtedly the most important component of any seismic risk assessment study that involves time-history analysis. Ironically, this is also the single parameter with the least guidance provided in current building codes, resulting in the use of mostly subjective choices in design. The relevant research to date has been primarily on single-degree-of-freedom systems, with only a few studies using multi-degree-of-freedom systems. Furthermore, the previous research is based solely on numerical simulations with no experimental data available for the validation of the results. By contrast, the research effort described in this paper focuses on an experimental evaluation of selected ground motion scaling methods based on small-scale shake-table experiments of re-configurable linear-elastic and nonlinear multi-story building frame structure models. Ultimately, the experimental results will lead to the development of guidelines and procedures to achieve reliable demand estimates from nonlinear response history analysis in seismic design. In this paper, an overview of this research effort is discussed and preliminary results based on linear-elastic dynamic response are presented.
Arsenic (As) distribution and toxicology in the environment is a serious issue, with millions of individuals worldwide being affected by As toxicosis. Sources of As contamination are both natural and anthropogenic and the scale of contamination ranges from local to regional. There are many areas of research that are being actively pursued to address the As contamination problem. These include new methods of screening for As in the field, determining the epidemiology of As in humans, and identifying the risk of As uptake in agriculture. Remediation of As-affected water supplies is important and research includes assessing natural remediation potential as well as phytoremediation. Another area of active research is on the microbially mediated biogeochemical interactions of As in the environment. In 2005, a conference was convened to bring together scientists involved in many of the different areas of As research. In this paper, we present a synthesis of the As issues in the light of long-standing research and with regards to the new findings presented at this conference. This contribution provides a backdrop to the issues raised at the conference together with an overview of contemporary and historical issues of As contamination and health impacts.
The research outlined in this paper marks an initial global cooperative effort between visualization and collaboration researchers to build a persistent virtual visualization facility linked by ultra-high-speed optical networks. The goal is to enable the comprehensive and synergistic research and development of the necessary hardware, software and interaction techniques to realize the next generation of end-user tools for scientists to collaborate on the global Lambda Grid. This paper outlines some of the visualization research projects that were demonstrated at the iGrid 2005 workshop in San Diego, California.
This collection of 43 short papers is the last of the chapters of Geological Survey Research 1964. The papers report on scientific and economic results of current work by members of the Geologic, Conservation, Water Resources, and Topographic Divisions of the U.S. Geological Survey. Some of the papers present results of completed parts of continuing investigations; others announce new discoveries or preliminary results of investigations that will be discussed in greater detail in reports to be published in the future. Still others are. scientific notes of limited scope, and short papers on techniques and instrumentation. Chapter A of this series presents a summary of results of work done during the present fiscal year.