2,600 research outputs found
Impacts of the sustainable forestry initiative landscape level measures on hydrological processes
The effects on hydrological processes of the application of the landscape level measures included in the sustainable forestry initiative (SFI) program were analyzed through simulation. A landscape scenario where limitation of harvesting units’ size, imposition of a green-up interval, and establishment of streamside management zones (SMZ) were simulatedwas compared with a reference scenario where no SFI rules were followed. An intensively managed forested landscape located in
East Texas, USA, was used as the study area. The HARVEST landscape model was used to simulate landscape pattern and a modified version of the APEX model was used to simulate hydrological processes. Water and sediment yields were generally small within the observation period and most
of the runoff and erosion observed occurred during intense storm events. Water and sediment yield at the subarea level and water yield at the watershed level were similar in both scenarios. However,
sediment yield at the watershed level was higher in the non-SFI scenario. The differences were due to the reduction in channel erosion resulting from the presence of SMZs. The effect of buffer zones
in terms of sediment deposition was not different between scenarios, which can be attributed to the level slopes of the study area. Landscape measures of the SFI program, namely buffer zones, seem
important in reducing channel degradation, particularly during major storm events, in intensively managed forest landscapes in East Texas.PRODEP II
20GHz picosecond pulse generation by 1300nm mode-locked quantum dot master oscillator power amplifier
An integrated 1300 nm QD mode-locked narrow stripe MOPA is shown to generate 10.5 ps Fourier transform limited pulses at 20 GHz. The pulse train has an average power of 46.4 mW and peak powers exceeding 0.31 W
Effects of the Sustainable Forestry Initiative on Landscape Pattern and Processes
We used simulation modeling to study the changes in landscape pattern and function resulting from the application of the Sustainable Forestry Initiative (SFI) program in East Texas, USA. Changes in landscape structure were examined by comparing landscapes with different management histories. The effects of pattern on processes were analyzed considering vertebrate habitat quality and configuration and hydrological processes such as water and sediment yield. Landscapes managed according to the SFI program presented increased general fragmentation. The application of measures under SFI increased habitat diversity in the landscape as well as Habitat Suitability Index (HSI) values for most of the species. Habitat for species requiring large patches of mature forest was almost absent. Landscapes managed under the SFI program showed lower sediment yield at the watershed level than those under the non-SFI program due to higher channel erosion related to the absence of buffer strips in the non-SFI scenario
The role of the sustainable forestry Initiative in forest landscape changes in Texas, USA
We studied the changes in landscape pattern and function resulting from the application of the Sustainable Forestry Initiative (SFI) in East Texas, USA. Changes in landscape structure were studied by comparing land-scapes with different management histories. A methodology to integrate landscape and stand pattern dynamics with processes was developed based upon modeling and simulation. The effects of pattern on processes were analyzed with this methodology considering the quality, quantity and con-figuration of vertebrate habitat and hydrological processes.
Comparisons among landscapes revealed that forest management has a strong influence on landscape structure. The SFI program has increased overall fragmentation with an increase in number of patches, length of edges and shape complexity and a decrease in patch size, and number and size of core areas.
Management according to the SFI program resulted generally in higher habitat suitability for many of the species analyzed and higher habitat di-versity in the landscape. The SFI program induced fragmentation of the habitat of pine warbler and the establishment of narrow and elongated habitats in a network structure for most of the remaining species. Land-scapes managed under the SFI program showed lower sediment yield at the watershed level than those under the non-SFI program due to lower channel erosion. The effects of the SFI program at the landscape level are related to the network of buffer strips.
In general we conclude that relevant measures at the landscape level improve the sustainability of forested landscapes in East Texas
Wandering globular clusters: the first dwarf galaxies in the universe?
In the last decade we witness an advent of new types of dwarf stellar systems
in cluding ultra-compact dwarfs, ultra-faint dwarf spheroidals, and exotic
globular clusters, breaking the old simple paradigm for dwarf galaxies and
globular clusters. These objects become more intriguing, and understanding of
these new findings be comes more challenging. Recently we discovered a new type
of large scale structure in the Virgo cluster of galaxies: it is composed of
globular clusters. Globular clusters in Virgo are found wandering between
galaxies (intracluster globular clusters) as well as in galaxies. These
intracluster globular clusters fill a significant fraction in the area of the
Virgo cluster and they are dominated by blue globular clusters. These
intracluster globular clusters may be closely related with the first dwarf
galaxies in the universe.Comment: 6 pages, 3 figures, Conference Proceedings: "A Universe of Dwarf
Galaxies", 14-18 June 2010, Lyon, Franc
Methods for the recognition of geological weakness zones and other surface discontinuities caused by underground mining in Carboniferous terrain
Since March 1992 the British Geological Survey (BGS) has collaborated in a CEC part-funded project under the leadership of Dr Clasen of Saarberg, Saarbrueken, Germany. The aim of this project was to determine the most efficient combination of surface geophysical techniques to be used in combination with airborne optical scanning data for the routine detection of shallow faults. Such features, when reactivated following undermining, may become the locii of damaging subsidence, but where they can be traced in advance of mining operations then remedial measures (such as underpinning etc) may be undertaken. This final report outlines the geophysical methods applied and describes our most significant results. Conclusions are drawn concerning the relative efficiencies of each technique and possible
complementary applications
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Quantitative Microanalysis with high Spatial Resolution: Application of FEG-DTEM XEDS Microanalysis to the Characterization of Complex Microstructures in Irradiated Low Alloy Steet
To assist in the characterization of microstructural changes associated with irradiation damage in low alloy steels, the technique of quantitative x-ray mapping using a field emission gun scanning transmission electron microscope (FEG-STEM) equipped with an x-ray energy Dispersive spectrometer (XEDS) has been employed. Quantitative XEDS microanalyses of the matrix and grain boundaries of irradiated specimens have been compared with previous quantitative analyses obtained using 3D-Atom Probe Field-Ion Microscopy (3D-APFIM). In addition, the FEG-STEM XEDS maps obtained from the irradiated steel have revealed the presence of 2 to 3 nm Ni-enriched 'precipitates' in the matrix, which had previously been detected using 3D-APFIM. These quantitative FEG-STEM XEDS results represent the first direct and independent microchemical corroboration of the 3D-APFIM results showing ultra-fine irradiation-induced hardening features in low alloy steel
Nonperturbative QCD Vacuum Effects in Nonlocal Quark Dynamics
A straightforward calculation reveals the essentially nonlocal character of
the leading heavy interaction arising from nonperturbative gluon
field correlations in the model of a fluctuating QCD vacuum. In light of this
quarkonium spin splitting ratio predictions which have supported the scalar
confinement ansatz are reconsidered as a specific example of possible
consequences for spectroscopy.Comment: Latex, 9 page
The Holocene fluvial sedimentary record and alluvial geoarchaeology in the Nile Valley of northern Sudan
A Placebo‐Controlled Double‐Blinded Randomized Pilot Study of Combination Phytotherapy in Biochemically Recurrent Prostate Cancer
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136500/1/pros23317_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136500/2/pros23317.pd
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