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Towards Sustainable Harvest of Sideneck River Turtles (<italic>Podocnemis spp.</italic>) in the Middle Orinoco, VenezuelaPenaloza, Claudia January 2010 (has links)
<p>Despite 21 years of protection, sideneck river-turtles (<italic>Podocnemis expansa</italic>, <italic>P. unifilis</italic> and <italic>P. vogli</italic>, arrau, terecay and galápago, respectively), an important food resource for riverine communities (<italic>ribereños</italic>) in the Middle Orinoco, have not recovered. To determine the most effective conservation alternative for recovery, we conducted semi-structured interviews of ribereños and determined their attitudes towards turtle conservation; we collected discarded turtle remains in riverine communities to estimate the level of turtle harvest; and constructed a population model to study the effect of reduced survival and future extraction on arrau turtle population growth. We found that ribereños blame continued commercial extraction for the lack of turtle population recovery. Ribereños have a desire to participate actively in conservation and, despite feeling alienated by governmental officials charged with protecting turtles, prefer to be included in conservation efforts. However, ribereños also fear retaliation from turtle poachers. We found widespread turtle harvest along the Middle Orinoco centered on juvenile arrau turtles, and adult female terecay and galápago turtles. In our population model, reducing harvest causes an increase in population growth. A 10% increase in survival causes rapid exponential growth in arrau turtles. The population continues to grow in over 70% of projected scenarios with limited harvest from a recovered stock. Due to the widespread distribution of turtles and their harvest, we recommend increasing ribereño participation in conservation activities, closing outsider (non-ribereño) access to the resource, increasing enforcement against illegal commercial harvest, instating possession limits for subsistence harvest, and promoting localized captive breeding of faster maturing terecay and galápago turtles to satisfy desire for turtle consumption.</p> / Dissertation
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Assessing ecosystem response to natural and anthropogenic disturbances using an eco-hydrological modelAbdelnour, Alex Gabriel 14 November 2011 (has links)
The impact of natural and anthropogenic disturbances on catchment hydrological and biogeochemical dynamics are difficult or impossible to capture through experimentation or observation alone. Process-based simulation models can address this need by providing a framework for synthesizing data describing catchment responses to climate, harvest, fire, and other disturbances. However, existing models are either too simple to capture important process-level hydrological and biogeochemical controls on ecosystem responses to disturbance, or are too computationally expensive to simulate the local dynamics over large watershed areas, or require a high level of expertise to implement.
To this end, a spatially distributed, physically based, eco-hydrological model (VELMA: Visualizing Ecosystems for Land Management Assessments) that is both computationally efficient and relatively easy to implement is developed. VELMA is a state-of-the-art model with real-time visualization tools that shows temporal and spatial patterns of state and flux variables, and is used to address the effects of changes in climate, land-use, and other interacting stressors on multiple ecosystem services such as timber production, carbon sequestration, regulation of water quality and quantity and reduction of greenhouse gases at scales relevant to formulating management decisions.
In this study, VELMA was applied to the H.J. Andrews Experimental forest, an intensively studied watershed with observed daily temperature, precipitation, streamflow, and nutrient losses data. VELMA was first used to explore the factors that controls catchment response to forest harvest. Specifically, elucidate how forest harvest factors such as harvest location and amount control watershed hydrological and biogeochemical fluxes. Thereafter, VELMA was used to reconstruct and analyze the impact of two significant disturbance events − a stand replacing fire and a 100% clearcut − on vegetation and soil carbon and nitrogen dynamics. Finally, VELMA was used to explore the potential impact of climate change on catchment hydrological regime, site productivity and carbon and nitrogen dynamics at high spatial resolution relevant to formulating management decision.
The main insights from this study include: (1) streamflow, nutrient losses to the stream, and gaseous carbon and nitrogen losses to the atmosphere are strongly sensitive to the location of harvest as a result of the spatial variation in soil water content, plant nitrogen uptake, soil organic carbon decomposition, nitrification, and denitrification within the watershed, (2) forested riparian buffers reduce water and nutrient losses to the stream through plant transpiration, plant nitrogen uptake, soil storage, and soil microbial decomposition, (3) following fire and harvest, losses of N from the terrestrial system to the stream are tightly constrained by the hydrological cycle and driven mainly by wet-season rain events large enough to generate hydrologic connectivity and flushing of nutrients along hillslopes, (4) climate change strongly impacts the hydrological regime in the Pacific Northwest as a result of less snowpack, earlier snowmelt, higher winter streamflow, lower summer streamflow, and soil moisture deficit, and (5) climate change increases plant and soil biomass accumulation as a result of longer growing season and higher soil organic decomposition, reduce water quality by increasing the amount of nutrients that reach the stream, and transforms the ecosystem into a net source of carbon to the atmosphere.
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Workshop Metacomputing 9625 March 1996 (has links)
Vortragsfolge
Prof. Uwe Huebner: Metacomputing - neue Aufgabenverteilung im Netz
Dr. Wolfgang Riedel: Was nuetzt uns SGML
Sven Graupner: What's up in Operating System Research
Sven Koehler: IP Security (nach RFC 1825)
Holger Trapp: Kryptographisch gesicherte Kommunikation und Datenhaltung
Dr. Joerg Anders: ATM-Eine kritische Betrachtung
Guenther Fischer: Cacheserver-Hierarchien
Frank Richter: Ein neuer WWW-Server fuer www.tu-chemnitz.de
Steffen Brose: Web-Zugang zu DQS
Jens Kraizci, Volker Holfeld: Wie weiter mit dem CSN?
Jan Wunderlich: Harvest
Michael Hasenstein: Datenbank-Klienten auf Java-Basis
Andreas Koehler: Form-based File Upload in HTML
Gerd Heide: BROADWAY - Interaktivitaet im WWW mittels X-Protokoll
Matthias Ehrig: NFS 2 - Moeglichkeiten und Grenzen
Ronald Koehler: NFS 3
Christoph Ziegler: HSM - Was verbirgt sich dahinter?
Kai Zscheile: Hardware-Loesungen fuer HSM
Matthias Clauss: Vergleich und Bewertung von HSM-Loesungen
Thomas Mueller: Fileserving an der TUCZ
Karsten Baensch: AFS-Loesung fuer die Softwareumgebung der Parsytec-Maschinen
Joern Wohlrab: Alternative verteilte Filesysteme
Jens Junghaenel: Integration von PC's mittels Samba
Merten Schumann: Archivierung elektronisch publizierter Dokumente
Michael Tautenhahn: Fast Ethernet
Jens Wagner: Firmenadressverwaltung am URZ
Dr . Wolfgang Riedel: Neues aus der TeX-Welt (METAPOST, lyx)
Carsten Mund: Untersuchung von Einflussfaktoren auf SPEC CINT- und CFP-Benchmarks
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The effects of wildfire disturbance and streamside clearcut harvesting on instream wood and small stream geomorphology in south-central British ColumbiaScherer, Robert Andrew 05 1900 (has links)
Few field studies have assessed the temporal and spatial dynamics of wood in small streams (bankfull widths < 5 m) flowing through forest ecosystems dominated by stand replacing wildfires. Comparisons of instream wood loads associated with clearcut harvesting, wildfire, and undisturbed, old forests are also scarce. The two main objectives of this research were: (1) to document the temporal and spatial variability of wood and its geomorphic role in relation to stand development stage; and (2) to compare wood loads and its geomorphic role in relation to streamside clearcut harvesting, wildfires and older, undisturbed forest stands. This research focused on 38 small streams with gradients less than 14% situated in the plateau regions of south-central British Columbia, Canada.
A distinct temporal trend in wood loading was observed, with elevated volumes present 30-50 years subsequent to the wildfire disturbances following a “reverse J-shaped” trend in relation to time since the last major wildfire disturbance. The number of wood pieces was highly variable and few of the wood characteristics exhibited a significant trend in relation to time since the last major wildfire disturbance. Except at the smallest spatial scale (<3 m segments longitudinally along the stream) the spatial distribution of wood followed a random pattern with no trend, indicating that wood loads are related to local wood recruitment processes associated with episodic or chronic tree mortality and low wood transport.
Instream wood volumes were three times higher in streams recently (30 – 50 years ago) disturbed by wildfire as compared to the older riparian forest stands, confirming that wildfire disturbance is an important mechanism to recruit wood into streams. No significant differences in wood loads were identified between the streamside clearcut streams and the wildfire-disturbed or older, undisturbed streams. The lack of reductions in wood loads are likely related to the low transport capacity of our study streams, retention of non-merchantable trees and recruitment of slash from harvesting. A lack of morphologic variability was observed in relation to the disturbances indicating that the streams included in this study are relatively robust and unresponsive to wildfire or streamside clearcut harvesting disturbances.
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Volunteer spring triticale (× Triticosecale Wittmack) seed persistence and controlRaatz, Lisa L Unknown Date
No description available.
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Evaluating Surgical Outcomes: A Systematic Comparison of Evidence from Randomized Trials and Observational Studies in Laparoscopic Colorectal Cancer SurgeryMartel, Guillaume 10 January 2012 (has links)
Background: Laparoscopic surgery for colorectal cancer is a novel healthcare technology, for which much research evidence has been published. The objectives of this work were to compare the oncologic outcomes of this technology across different study types, and to define patterns of adoption on the basis of the literature.
Methods: A comprehensive systematic review of the literature was conducted using 1) existing systematic reviews, 2) randomized controlled trials (RCTs), and 3) observational studies. Outcomes of interest were overall survival, and total lymph node harvest. Outcomes were compared for congruence. Adoption was evaluated by means of summary expert opinions in the literature.
Results: 1) Existing systematic reviews were of low to moderate quality and displayed evidence of overlap and duplication. 2) Laparoscopy was not inferior to open surgery in terms of oncologic outcomes in any study type. 3) Oncologic outcomes from RCTs and observational studies were congruent. 4) Expert opinion in the literature has been supportive of this technology, paralleling the publication of large RCTs.
Conclusions: The evaluation of laparoscopic surgery for colorectal cancer in RCTs and observational studies suggests that it is not inferior to open surgery. Adoption of this technology has paralleled RCT evidence.
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Characterization of Forest Harvest Residue from the Great Lakes-St Lawrence Forests of South-eastern OntarioAcquah, Gifty Ewurama 14 December 2010 (has links)
The use of fossil derived products and the environmental and economic problems associated with them have made a shift to abundant renewable resources such as forest biomass more attractive. However before forest biomass can be used as a resource, its properties must be known.
This study determined the physical properties of heterogeneous biomass residues produced during harvesting on two operational forest sites within the Great Lakes-St Lawrence forest of south-eastern Ontario. Properties measured were moisture content, size distribution, bulk density, and wood-to-bark ratio; also thermo-chemical properties including elemental composition, thermal reactivity and energy content were measured. The effects of forest site and harvest type, storage and position in storage pile, on the properties of biomass were also investigated.
Results of the study showed that the various heterogeneous forest harvest residues differed more physically than thermo-chemically for the different variables, and this affected biomass procurement more than the potential utilization options.
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Leading selected church members in developing a ministry-driven strategy for family members of chemically addicted persons in Capshaw Baptist Church of Harvest, AlabamaAshford, William H., January 2005 (has links)
Thesis (D. Min.)--New Orleans Baptist Theological Seminary, 2005. / Includes abstract and vita. Includes project proposal. Includes bibliographical references (leaves 225-228).
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Leading selected church members in developing a ministry-driven strategy for family members of chemically addicted persons in Capshaw Baptist Church of Harvest, AlabamaAshford, William H., January 1900 (has links)
Thesis (D. Min.)--New Orleans Baptist Theological Seminary, 2005. / Includes abstract and vita. Includes project proposal. Includes bibliographical references (leaves 225-228).
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The use of time study, method study and GPS tracking in improving operational harvest planning in terms of system productivity and costsOdhiambo, Benedict O. 12 1900 (has links)
Thesis (MScFor (Dept. of Forest and Wood Science)--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: This study aims to quantify the benefits of implementing an operational
harvesting plan in forest harvesting operations. This is to be achieved by
comparing productivity and costs from unplanned and planned harvesting
operations. The study was conducted on a Pinus radiata plantation owned
by Mountain to Ocean Forestry Company (Pty) Ltd (MTO) located near the
town of Grabouw in the Western Cape Province of South Africa.
MTO conducts harvesting operations using semi-mechanised tree-length
harvesting systems. A wheeled H67 Clark Ranger cable skidder is used to
extract tree-lengths from infield to the landing. Data was obtained both
manually (work study) and from GPS tracking. Choking and dechoking data
was obtained through time and method studies. GPS tracking was used to
measure travel loaded and travel empty times, as well as travel distances
and travel speeds. The aim of using both manual techniques and GPS
tracking was to obtain detailed and spatially accurate information about the
operation. The operating costs were estimated using South African
Harvesting and Transport Costing Model.
Productivity of the newly introduced tagline system (45.97 m³/pmh) exceeded
that of mainline system (37.85 m³/pmhh) by 26%. The unit production cost of
using tagline system (R20.21/m³) was 10% lower than the unit production
cost of using mainline system (R22.54/³3). There were no benefits to be
gained from improving the level of skid trail construction by removal of
logging residue or cutting down stumps to as near the ground level as
possible. A combination of manual (time and method studies) data collection
and GPS tracking provided more detailed and accurate information on the
semi-mechanised harvesting system. / AFRKAANSE OPSOMMING: Hierdie studie beoog om die voordele van die uitvoering van 'n operasionele
inoestingsplan te kwantifiseer. Dit word bereik deur produktiwiteit en kostes
van beplande en onbeplande inoestingswerksaamhede te vergelyk. Die
studie is gedoen in Pinus radiata opstande van Mountain to Ocean Forestry
Company (Pty) Ltd (MTO) naby Grabouw in die Wes-Kaap provinsie van
Suid Afrika.
MTO gebruik semi-gemeganiseerde boomlengte inoestingstelsels in hul
inoestingswerksaamhede. . H67 Clark Ranger wielsleeptrekker met kabel en
wenas is gebruik om boomlengtes van die veld na die pad te sleep. Data is
versamel deur van beide hand (werkstudie) en GPS-opsporing gebruik te
maak. Afhaak en aanhaak data is verkry deur van tyd- en metodestudies
gebruik te maak. Gelaaide en ongelaaide tyd, spoed en afstande is met
behulp van die GPS gemeet. Deur van beide hand en GPS
versamelingsmetodes gebruik te maak, kon omvattende sowel as ruimtelik
akkurate inligting oor die werksaamhede verkry word. Die bedryfskostes is
verkry van die South African Harvesting and Transport Costing Model.
Produktiwiteit van die nuut ingestelde verbindingslynstelsel (45.97 m³/pmh)
het die hooflynstelsel (37.85 m³/pmh) met 26% oorskry. Die
eenheidsproduksiekoste van die verbindingslynstelsel (R20.21/m³) was 10%
laer as die eenheidsproduksiekoste van die hooflynstelsel (R22.54/m³). Daar
was geen voordeel in die verbetering van die sleeppad konstruksie deur afval
te verwyder of stompe nader aan die grondvlak af te sny nie. 'n Kombinasie
van hand (tyd- en metodestudies) dataversameling en GPS-opsporing het
meer akkurate en omvattende inligting oor die semi-gemeganiseerde
inoestingstelsel verskaf.
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