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  • Kerchner, C. D.; Keeton, W. S. (Forest Policy and Economics, 2015
      Carbon markets have the potential to reward landowners for improved forest management and forest conservation. To date, the Over the Counter (OTC) voluntary market represents the greatest opportunity for forest landowners to participate in carbon transactions. However, lack of a consistent carbon price signal and sporadic demand coupled by high transaction costs has prevented widespread participation from family forest landowners. Adoption of a U.S. based cap-and-trade program reduces price risk and may provide incentives for sustainable forest management across large areas. Yet few studies have examined the supply side of carbon offsets and factors affecting project financial viability. To address this gap, we assessed how (1) property characteristics (i.e. stocking level, forest type, size etc.); (2) silvicultural treatments; and (3) protocol and legislative requirements affect the financial viability of compliance forest offset projects, focusing on California's Air Resource Board (ARE) program due to its significance as the world's second largest carbon market. We used forest inventory data from 25 properties in the northeastern United States to examine the viability of the sites as ARE offset projects. We utilized the U.S. Forest Service Forest Vegetation Simulator for our growth and yield simulations. To examine the factors that influence project viability, we used a classification and regression tree analysis performed in S-Plus software. Results indicate C stocking and property size are the most important property characteristics driving return on investment. However, protocol requirements and legislative assumptions impacting long-term monitoring costs are also important factors. While reduced price risk in a compliance carbon market has the potential to improve forest management in North America; high initial project development costs, long-term monitoring obligations, and legislative uncertainty are significant barriers that will limit family forest landowner market participation. The model developed here can be used by U.S. landowners to assess the financial viability of their property as a compliance offset project and can be utilized by policymakers to develop cost-effective climate change policy. (C) 2014 Elsevier B.V. All rights reserved.
  • Schwenk, W. S.; Donovan, T. M.; Keeton, W. S.; Nunery, J. S. (Ecological Applications, 2012
      Increasingly, land managers seek ways to manage forests for multiple ecosystem services and functions, yet considerable challenges exist in comparing disparate services and balancing trade-offs among them. We applied multi-criteria decision analysis (MCDA) and forest simulation models to simultaneously consider three objectives: (1) storing carbon, (2) producing timber and wood products, and (3) sustaining biodiversity. We used the Forest Vegetation Simulator (FVS) applied to 42 northern hardwood sites to simulate forest development over 100 years and to estimate carbon storage and timber production. We estimated biodiversity implications with occupancy models for 51 terrestrial bird species that were linked to FVS outputs. We simulated four alternative management prescriptions that spanned a range of harvesting intensities and forest structure retention. We found that silvicultural approaches emphasizing less frequent harvesting and greater structural retention could be expected to achieve the greatest net carbon storage but also produce less timber. More intensive prescriptions would enhance biodiversity because positive responses of early successional species exceeded negative responses of late successional species within the heavily forested study area. The combinations of weights assigned to objectives had a large influence on which prescriptions were scored as optimal. Overall, we found that a diversity of silvicultural approaches is likely to be preferable to any single approach, emphasizing the need for landscape-scale management to provide a full range of ecosystem goods and services. Our analytical framework that combined MCDA with forest simulation modeling was a powerful tool in understanding trade-offs among management objectives and how they can be simultaneously accommodated.
  • Wilson, Sandra (2005-10-18
      a Catharanthus selection that took 8 years to release
  • McMahon, Peg (2006-07-07
      Celosia is a colorful bedding plant that comes in two forms, cockscomb and plume.
  • McMahon, Peg (2006-07-07
      Celosia is a colorful bedding plant that has two types of flowers, cockscomb shown here and plume.
  • McMahon, Peg (2006-07-07
      Celosia is a colorful bedding plant that has two types of flowers, plume shown here and cockscomb.
  • Mills, R. W.; Koliba, C. J. (Regulation & GovernanceRegul. Gov., 2015
      A puzzle that faces public administrators within regulatory governance networks is how to balance the need for democratic accountability while increasingly facing demands from elected officials to optimize oversight of industry by utilizing the expertise of the private sector in developing risk-based standards for compliance. The shift from traditional command and control oversight to process oriented regulatory regimes has been most pronounced in highly complex industries, such as aviation and deepwater oil drilling, where the intricate and technical nature of operations necessitates risk-based regulatory networks based largely on voluntary compliance with mutually agreed upon standards. The question addressed in this paper is how the shift to process oriented regimes affects the trade-offs between democratic, market, and administrative accountability frames, and what factors determine the dominant accountability frame within the network. Using post-incident document analysis, this paper provides a case study of regulatory oversight of the deepwater oil drilling industry prior to the explosion of the Deepwater Horizon rig in the Gulf of Mexico, to explore how the shift to a more networked risk-based regulatory regime affects the trade-offs and dominant accountability frames within the network. The results of this study indicate that a reliance on market-based accountability mechanisms, along with the lack of a fully implemented process-oriented regulatory regime, led to the largest oil spill in US history.
  • Costanza, R.; Kubiszewski, I.; Roman, J.; Sutton, P. (Migration and Global Environmental Change, 2011
      This paper examines the history and current status of ecosystem services in low-lying coastal areas (LLCAs), their potential changes because of wider environmental and social shifts, and the potential impacts of these changes on human migration. We synthesised information from a number of sources on the status and value of ecosystem services in LLCAs, including information about key ecosystems that are likely to be particularly vulnerable to environmental change. We created maps of ecosystem and human population changes in LLCAs and then estimated changes in ecosystem services. Estimating the impacts of these potential changes depends on the future scenario one assumes. For our analysis four scenarios were developed for future ecosystem and ecosystem services conditions in 2060, based on the four SRES (Special Report on Emissions Scenarios) scenarios with additional reference to the Millennium Ecosystem Assessment and the Great Transition Initiative scenarios. The two axes of the SRES scenarios are global vs. regional and material economy vs. environment foci. This allowed an assessment of the plausible range of future uncertainty about ecosystem services in LLCAs and the potential for changes in ecosystem services to drive human migration.
  • McMahon, Margaret (2004-10-13
      Chapin water system laid out and ready for plants
  • Guilbert, J.; Betts, A. K.; Rizzo, D. M.; Beckage, B.; Bomblies, A. (Geophysical Research Letters, 2015
      We present evidence of increasing persistence in daily precipitation in the northeastern United States that suggests that global circulation changes are affecting regional precipitation patterns. Meteorological data from 222 stations in 10 northeastern states are analyzed using Markov chain parameter estimates to demonstrate that a significant mode of precipitation variability is the persistence of precipitation events. We find that the largest region-wide trend in wet persistence (i.e., the probability of precipitation in 1day and given precipitation in the preceding day) occurs in June (+0.9% probability per decade over all stations). We also find that the study region is experiencing an increase in the magnitude of high-intensity precipitation events. The largest increases in the 95th percentile of daily precipitation occurred in April with a trend of +0.7mm/d/decade. We discuss the implications of the observed precipitation signals for watershed hydrology and flood risk.
  • Stephens, Jennie C.; Hansson, Anders; Liu, Yue; de Coninck, Heleen; Vajjhala, Shalini (Global Environmental Change-Human and Policy Dimensions, 2011
      Carbon capture and storage (CCS) is a controversial climate change mitigation technology that has been receiving increased public and private investment over the past decade in several countries. During this time, a diverse international network of professionals focused on the advancement of CCS technology has emerged. Within this international CCS community, a shared perception of the value of advancing CCS technology is generally assumed, and this community has been influential in lobbying for increased support for the development of CCS in many countries and at the international level. The phenomenon of an apparently shared perspective within a specific community relates to Haas' (1992a) description of the evolution of an epistemic community, or a knowledge-based network of recognized experts who "not only hold in common a set of principled and causal beliefs but also have shared notions of validity and a shared policy enterprise". Understanding the extent to which a given community can be characterized as an epistemic community can provide insights about the effectiveness of its policy intervention, its association with the broader public, and the success of communicating the messages that it wants to convey. The goal of this research is to begin to explore the nature of the CCS community; to provide a preliminary characterization of the community, and to consider whether and in what ways the community might be considered to be an epistemic community or a compilation of multiple different epistemic communities. This characterization suggests that although the CCS community may be influencing decision-makers and successfully garnering political support for advancing CCS technology, a potential disconnect with the concerns of a broader public is deserving of more attention and social science research. (C) 2011 Elsevier Ltd. All rights reserved.
  • Balogh-Brunstad, Z.; Keller, C. K.; Bormann, B. T.; O'Brien, R.; Wang, D.; Hawley, G. J. (Global Biogeochemical Cycles, 2008
      Mineral weathering and chemical denudation of terrestrial environments are understood by both geochemists and ecologists to be affected by rooted plant growth. We used unique 20-year "sandbox'' experiments to test the predictions of both disciplines regarding the influence of tree growth and harvest on chemical weathering and denudation of Ca(2+), Mg(2+) and K(+). Results showed 3 temporal phases: 1) weathering-dominated rapid uptake of mineral nutrients with retention in trees and soil, and low denudation; 2) biocycling-dominated nutrient uptake with slower tree growth, and chemical fluxes reduced to near zero; and 3) denudation-dominated loss of nutrient reserves after harvest by disruption of biotic regulation. Overall, a red pine sandbox used and retained its resources more effectively than a reference non-vascular system. The results suggest that disturbance may be an important factor controlling chemical denudation rates. Temporal variations of the fluxes highlight difficulties of extrapolating weathering and denudation rates over long timescales.
  • Tignor, Milton (2005-03-17
      cherry tomato vines wrap around the row as the plants are lowered. Lower leaves are removed as plants grow taller.
  • Unknown author (2005-07-08
  • Unknown author (2005-06-07
  • Unknown author (2005-06-20
  • Wilson, Sandra (2006-03-28
      Image looking down aisle of mum propagation facility. Plants are grown for stock blocks used in cutting production.
  • Wilson, Sandra (2005-12-22
      Thousands and thousands of Chrysanthemum cuttings are growing in this greenhouse range. Note the mist irrigation emitters high in ceiling of greenhouse.
  • Heleba, David (2005-11-30
      Grafted citrus plants in large square deep pots to enhance tap root growth. The pots on right are same depth as left. Mist emitters can be seen below roof trusses running down length of greenhouse. You can see saw toothed pattern of roof ridge on upper right side of image. The roof vent is open in this image. Fiberglass side wall at far end of image is discolored due to age.

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