1,232 research outputs found
Coarse Root Biomass and Architecture: Applications of Ground Penetrating Radar
The effectiveness of ground penetrating radar (GPR) to identify and quantify coarse roots was tested in a mixed-oak forest in Southeastern Virginia using experimental pits and locally excavated root segments. GPR was found to be highly dependent on low soil moisture levels as it is unable to differentiate root structures if they possess similar moisture content as their surrounding soil. Likewise, GPR was unable to identify simulated dead roots. This does not alter the effectiveness of GPR to measure living coarse root biomass, but does present the potential for underestimation of carbon storage in coarse root structures, as a dead roots continue to store carbon. GPR was able to recognize and quantify increasing root density suggesting an ability to quantify change in root mass over time, but it was not able to reliably represent changes in root diameter.
Coarse root biomass estimation using GPR was conducted using a grid scanning technique applied to sample plots located within multiple systems. GPR effectively measured coarse root biomass across multiple systems, showing no significant difference between estimated and observed coarse root biomass in a Virginia mixed-oak forest ecosystem, a Florida scrub-oak ecosystem, or a Florida longleaf pine flatwoods ecosystem. GPR appears to have difficulty with root structures near the surface, as it is not able to reliably separate these structures from the soil-air interface.
Post-experimental disturbance effects were examined in a Florida scrub-oak ecosystem, following an 11-year open-top chamber elevated CO2 experiment that concluded in 2006 and had been abandoned for seven years. Aboveground harvest showed a significantly higher regrowth two years post fire in previously elevated CO2 plots when compared with plots that were kept at ambient CO2 levels throughout the duration of the original experiment. No significant difference was found in coarse root biomass between the two treatments; however, a non-significant trend of 12% higher biomass in the previously elevated CO2 plots was found that coincided with a similar trend observed during the original experiment. Long-lasting effects of elevated CO2 appear to exist within this system, indicating an ability for plants to store additional carbon and to regrow more rapidly following fire disturbance.
Carbon storage within coarse roots was examined in a Florida longleaf pine flatwoods ecosystem as part of a larger, ongoing effort to quantify total carbon storage and flux within multiple systems relative to longleaf pine restoration. Coarse root carbon storage was estimated at 3.5 – 3.7 kg C/m2, suggesting large carbon storage potential associated with longleaf pine restoration.
GPR is an effective, non-destructive tool for quantifying coarse root biomass and an effective but limited tool for determining root architecture. Both applications of GPR are highly dependent on user-determined settings during data collection and post-collection processing, thus effective GPR application is highly dependent on the level of familiarity possessed by the operator
The Colorado River Experience: Assessing The Value Of Motorized Rafting
Although free markets provide superior solutions to resource allocation, the National Park Service controls access, use, and mode of travel on the Colorado River through the canyon. There is an aggregate number of “user days” allowed for the river. There is a split between motorized and non-motorized travel, and daily limits on the types of trips that can be launched from Lees Ferry, the starting point for Grand Canyon river trips. This paper explores a rather straightforward economic question – How much would it take to entice existing motorized providers to switch to oar powered rafts? Available data allows the development of different scenarios to determine the cost of enticing motorized providers to switch to nonmotorized guided trips. However, there is also intrinsic some providers possess which may make change a purely economic decision to one with other values
Virginia Game Fish Tagging Program Annual Report 2002
The Virginia Game Fish Tagging Program (VGFTP), in its eighth year during 2002, systematically trains and assists anglers in tagging a select number of species important to Virginia\u27s marine recreational fishery and maintains the resulting tagging database. A cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), the program is primarily funded with revenues from Virginia\u27s saltwater recreational fishing license funds (Recreational Fishing Development Fund). In addition, support for the program is provided by Virginia\u27s Sea Grant Marine Advisory Program at VIMS
Virginia Game Fish Tagging Program Annual Report 2000
The Virginia Game Fish Tagging Program (VGFTP), in its sixth year during 2000, systematically trains and assists anglers in tagging a select number of species important to Virginia\u27s marine recreational fishery and maintains the resulting tagging database. A cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), the program is primarily funded with revenues from Virginia\u27s saltwater recreational fishing license funds (Recreational Fishing Development Fund). In addition, support for the program is provided by Virginia\u27s Sea Grant Marine Advisory Program at VIMS
Ensuring the Alignment of Genetic/Epigenetic Designed Swarms.
. One of the major concerns of AI researchers and implementers is how to ensure that the systems
stay aligned with the aspirations of the humans they interact with. This problem becomes even more
complex for systems that develop their own operational rules and where multiple agents are involved. The
paper addresses some of the implications of using genetic/epigenetic design techniques where the control
structure is developed without direct human involvement. This presents particular difficulties in ensuring
that the control protocols stay aligned with the desires of the instigators and do not cause unpredicted
harm. It also explores how this problem is further complicated when the AI system has many agents.
Modern control systems are often decentralized which provides a more robust solution than using a
central controller. A specific example of this approach is Self-Organising Swarms where the agents act
independently of the central control. From an alignment point of view, it generates particular problems.
Not only must the individual agents act in the best human interest but the swarm as a collective must do it
as well. This is difficult for a homogeneous swarm and no proposal for a heterogeneous one has yet been
made. There have been and continue to be considerable research and discussions on how to create and
what form a global AI ethics might take, but any progress has been slow. This is partly because even the
4 ISSN 1028-9763. Математичні машини і системи. 2022. № 1
Universal Declaration of Human Rights has difficulties. All the nations that have signed up to the UN
Human Rights Declaration believe they are at least trying to implement it. The problem is in the
interpretation where many signatories believe others are in breach. The same would apply to any
universal AI ethics agreement. This paper proposes a solution where the AI systems’ basic ethics are
individual but have to comply where they interface with either other AI entities or humans.
Keywords: genetic/epigenetic algorithms, AI alignment, AI ethics
Virginia Game Fish Tagging Program Annual Report 2006
The Virginia Game Fish Tagging Program (VGFTP), initiated in 1995, coordinates tagging and a tag-recapture fish database generated through contributed efforts of a dedicated corps of trained marine anglers. Through 2006, the program’s database includes over 103,000 tagged fish records of tag-released fish and approximately over 10,300 recapture records (Table 4)
Virginia Game Fish Tagging Program Annual Report 2001
The Virginia Game Fish Tagging Program (VGFTP), in its seventh year during 2001, systematically trains and assists anglers in tagging a select number of species important to Virginia\u27s marine recreational fishery and maintains the resulting tagging database. A cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), the program is primarily funded with revenues from Virginia\u27s saltwater recreational fishing license funds (Recreational Fishing Development Fund). In addition, support for the program is provided by Virginia\u27s Sea Grant Marine Advisory Program at VIMS
Virginia Game Fish Tagging Program Annual Report 2001
The Virginia Game Fish Tagging Program (VGFTP), in its seventh year during 2001, systematically trains and assists anglers in tagging a select number of species important to Virginia\u27s marine recreational fishery and maintains the resulting tagging database. A cooperative project of the Virginia Marine Resources Commission and the Virginia Institute of Marine Science (VIMS), the program is primarily funded with revenues from Virginia\u27s saltwater recreational fishing license funds (Recreational Fishing Development Fund). In addition, support for the program is provided by Virginia\u27s Sea Grant Marine Advisory Program at VIMS
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