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  • Zencey, Eric (The North American ReviewUniversity of Northern Iowa, New York, NY., 2007
  • Pagliarulo, Chris; Giacomelli, Gene (2005-07-15
  • Wright, Wesley (2005-03-14
      Lake Louise , Victoria Glacier, Chateau Lake Louise as seen from slope of Lake Louise ski resort
  • Erickson, Daniel L.; Lovell, Sarah Taylor; Mendez, V. Ernesto (Landscape and Urban Planning, 2011
      Throughout the world, urbanization is causing a loss of agricultural land as residential and commercial development expand. In Chittenden County, Vermont, U.S.A., this land use conversion has resulted in subdivision of farms into large residential parcels. Some of these residential parcels retain sizeable areas of undeveloped prime agricultural soil, yet the land is effectively removed from agricultural production. This study explored landowner willingness to enroll a portion of their land in a cooperative land management (CLM) scheme. Our results show support for embedding production agriculture and other cooperative land use options in residential parcels. Almost half of the respondents (45.6%) indicated they would enroll a portion of their land in a CLM program, while another 28.4% said "maybe". A cluster analysis partitioned the respondents into five clusters based on the following variables: percent agricultural land on parcel, parcel size, years in residence, and the population density of the town where the parcel is located. Willingness to participate in the CLM program and different land use options (livestock grazing, vegetables, fruit, field crops, biofuel, maple sugaring, wildflowers, medicinal plants, wildlife corridor, and recreational trails) varied across the clusters. A cluster containing a high percentage of agricultural land ("farms") had the highest support for production agriculture options, while a cluster of long term residents (old timers) had the lowest. These results are encouraging for farmers seeking access to affordable farmland and for planning efforts seeking increased regional landscape multifunctionality. (C) 2011 Elsevier B.V. All rights reserved.
  • Ricketts, T. H.; Regetz, J.; Steffan-Dewenter, I.; Cunningham, S. A.; Kremen, C.; Bogdanski, A.; Gemmill-Herren, B.; Greenleaf, S. S.; Klein, A. M.; Mayfield, M. M.; Morandin, L. A.; Ochieng, A.; Potts, S. G.; Viana, B. F. (Ecology Letters, 2008
      Pollination by bees and other animals increases the size, quality, or stability of harvests for 70% of leading global crops. Because native species pollinate many of these crops effectively, conserving habitats for wild pollinators within agricultural landscapes can help maintain pollination services. Using hierarchical Bayesian techniques, we synthesize the results of 23 studies – representing 16 crops on five continents – to estimate the general relationship between pollination services and distance from natural or semi-natural habitats. We find strong exponential declines in both pollinator richness and native visitation rate. Visitation rate declines more steeply, dropping to half of its maximum at 0.6 km from natural habitat, compared to 1.5 km for richness. Evidence of general decline in fruit and seed set – variables that directly affect yields – is less clear. Visitation rate drops more steeply in tropical compared with temperate regions, and slightly more steeply for social compared with solitary bees. Tropical crops pollinated primarily by social bees may therefore be most susceptible to pollination failure from habitat loss. Quantifying these general relationships can help predict consequences of land use change on pollinator communities and crop productivity, and can inform landscape conservation efforts that balance the needs of native species and people.
  • Puryear, Kristen (University of Vermont. Dept. of Botany, 2004-05
      Executive Summary Grassland birds are declining throughout most of their range. As a result, artificial habitats such as the agricultural fields of Vermont's Champlain Valley have been identified as important for grassland bird conservation. In order to address the regional and statewide concerns about grassland bird populations, Audubon Vermont has recognized two Important Bird Areas (IBAs) in the Champlain Valley, Dead Creek and Little Otter Creek. Audubon Vermont has also proposed the development of a Landscape-Level Important Bird Area Complex that would encompass these two IBAs and contribute to regional grassland bird conservation efforts as they are developed by the North American Bird Conservation Initiative and Partners in Flight. In the summer of 2003 I surveyed grassland birds in the two IBAs to assess the effects of agricultural management on breeding success. I also developed a habitat model that identifies the best potential habitat for grassland birds in the Champlain Valley , to help Audubon Vermont develop a strategy towards landscape-level grassland bird conservation. The following considerations for Audubon Vermont summarize my findings. For additional information about each consideration, please refer to the associated chapter, noted below. Grassland Bird Inventory (Chapter 1) Develop and implement a more extensive Upland Sandpiper monitoring program within Dead Creek and Little Otter Creek Important Bird Areas (IBAs) that will assess breeding success on an annual basis. Regularly monitor the same fields using a method that can detect breeding success (such as behavior mapping with a reproductive index [Vickery et al. 1992] or nest searching), which can provide information on breeding success, demographics, and responses to field management. Broadcasting surveys could be used as a supplemental tool for identifying additional survey fields and previously undetected individuals, and to help measure abundance. Monitor fields within the IBAs more than once during the breeding season to increase ,the chance of detecting rare species, assess breeding success, and help detect whether fields are ecological traps or sinks. Share field inventory results with the Vermont Department of Fish and Wildlife to help inform future revisions to their management plans for Dead Creek and Little Otter Creek Wildlife Management Areas (WMAs). Breeding Success and Field Management (Chapter 2) To maximize the potential for young to fledge, encourage a delay of mowing on hayfields until at least July 15, but preferably August 1. The later date will help protect species that fledge late or are attempting a second clutch after a failed nest attempt. On pastures being managed for grassland birds, encourage the reduction of stocking densities and delayed pasturing until July 15. Encourage a delay of mowing the pasture for forage until after July 15 (preferably August 1). Gather data on the day-to-day mowing trends within the two week period from late June to early July and on farmers needs for forage cut at that time. Assess the costs and benefits to the farmer and the grassland birds of delaying mowing for a few additional days during this critical breeding stage. Grassland Bird Survey Methods ( Chapter 3) If the monitoring objective is to calculate density, abundance and species richness values for grassland bird species, then point count surveys are recommended as a time efficient and informative method. This method is capable of detecting relative differences between survey areas. If the monitoring objective is to collect as much information as possible regarding species richness (i.e., detecting less abundant species or individuals that are sitting on nests and would likely be missed by a stationary observer), to detect breeding- related activity or breeding success, or to monitor trends as they change through the breeding season or with field management, then behavior mapping using a reproductive index (Vickery et al. 1992) is recommended as the most useful and potentially informative method. This is a reliable method for recording the progress of birds through the stages of breeding behavior (when compared with ground-truthed nest data), and provides a better approximation of bird abundance (when compared to point counts, which survey a smaller area). Landscape Level Grassland Bird Conservation Area (Chapter 4) The zones that are mapped as the "best" potential habitat should be ground- truthed in order to test the accuracy of the Scored Grassland Bird Habitat Map, and 1) verify that the mapped conditions currently exist (i.e., landcover type or amount of edge), and 2) test the assumptions made in terms of what constitutes the best habitat for grassland birds in the Champlain Valley. Gaps in knowledge of grassland bird distribution should be addressed, especially for species that could serve as focal species (Upland Sandpiper) or are rare and will require extra attention for management and protection (Grasshopper Sparrow and Sedge Wren). To enhance monitoring, land protection, management, and advocacy for grassland birds, a collaborative effort between interested organizations and agencies will be important. Collaborate with The Nature Conservancy of Vermont to create a strategy for grassland bird conservation that does not conflict with future Valley Clayplain Forest restoration. To maximize the potential for maintaining grassland bird species richness, abundance, number of breeding pairs, and potential for protecting species with large area requirements, consider protecting a complex of fields that together provide at least 50 ha but preferably 200 ha of habitat. Adjust the size, location, and management of protected fields according to species, population, or habitat conservation goals as those goals are developed. Consider the costs and benefits of locating grassland bird conservation efforts in heavily agricultural areas, where economic needs for higher productivity and intense field management decrease the chance that birds will breed successfully. Consider locating grassland bird conservation efforts in less agricultural areas that still contain suitable habitat but may be surrounded by land that is managed with less intensity. Less productive or wet fields should also be considered, as they are less likely to be managed as intensively. Within these areas, alternative farming practices (such as delayed mowing) may be more practical and more accepted by landowners and conservation organizations. Combining Grassland Bird and Marsh Bird Conservation (Chapter 5) Address the habitat needs of both grassland and marsh bird species by protecting and managing land where their habitat overlaps, such as upland fields that are adjacent to marshes.
  • Windhausen, L. J.; Braun, D. C.; Wang, D. (Kluwer Academic/Plenum Publishers, New York, NY.New York, NY, 2004
      We used a landscape scale approach to examine phosphorus retention in wetlands of the LaPlatte River basin (13,723 ha), Vermont. Total phosphorus (TP) export from 15 study catchments (149-1,396 ha) was measured on 18 dates, representing a range in seasons and hydrologic conditions. Multiple regression models were developed to relate TP export to 14 possible explanatory variables based on land cover/use, quantified using a geographic information system. Most wetland variables had significant (p < 0.10) negative relationships with TP export on at least 1 date. These relationships were strongest on 2 spring snowmelt events, when 31% of the annual TP export from the LaPlatte River basin occurred. Overall, the percentage of nonagricultural poorly and very poorly drained soils was the best representation of phosphorus sinks in the study catchments. Identifying lands with poorly drained soils and no known sources of phosphorus may be a more functional and simpler method of delineating P sinks in the landscape than identifying wetlands using jurisdictional definitions.
  • Zia, A. (Sustainability, 2012
      Global climate change, especially the phenomena of global warming, is expected to increase the intensity of land-falling hurricanes. Societal adaptation is needed to reduce vulnerability from increasingly intense hurricanes. This study quantifies the adaptation effects of potentially policy driven caps on housing densities and agricultural cover in coastal (and adjacent inland) areas vulnerable to hurricane damages in the Atlantic and Gulf Coastal regions of the U.S. Time series regressions, especially Prais-Winston and Autoregressive Moving Average (ARMA) models, are estimated to forecast the economic impacts of hurricanes of varying intensity, given that various patterns of land use emerge in the Atlantic and Gulf coastal states of the U.S. The Prais-Winston and ARMA models use observed time series data from 1900 to 2005 for inflation adjusted hurricane damages and socio-economic and land-use data in the coastal or inland regions where hurricanes caused those damages. The results from this study provide evidence that increases in housing density and agricultural cover cause significant rise in the de-trended inflation-adjusted damages. Further, higher intensity and frequency of land-falling hurricanes also significantly increase the economic damages. The evidence from this study implies that a medium to long term land use adaptation in the form of capping housing density and agricultural cover in the coastal (and adjacent inland) states can significantly reduce economic damages from intense hurricanes. Future studies must compare the benefits of such land use adaptation policies against the costs of development controls implied in housing density caps and agricultural land cover reductions.
  • Giacomelli, Gene (2005-05-05
      Large exhaust fan for ventilating greenhouse.
  • Heleba, David (2005-01-14
      Picture of large Modine hot water heater
  • Tignor, Milton (2005-03-31
      large open hanging baskets made of copper tubing and wire will be soon lined with sheet moss, potting soil, and plants
  • McMahon, Margaret (2004-10-18
      Shadecloth being used to protect large poinsettias from too much light. Demonstrates that sometimes even high-light requiring plants need shade.
  • Wilson, Sandra (2005-10-18
      smaller seed are subjected to standard germination tests performed in germination boxes containing moistened filter paper
  • Wilson, Sandra (2005-05-15
      Agristarts is a biological technology company that produces and sells tissue culture liners on a wholesale level. Micropropagated plantlets are mass produced clonally in the laboratory from mother stock plants.
  • Trudel, R. E.; Bomblies, A. (Parasites & VectorsParasites Vectors, 2011
      Background: Synthetic insecticides are employed in the widely-used currently favored malaria control techniques involving indoor residual spraying and treated bednets. These methods have repeatedly proven to be highly effective at reducing malaria incidence and prevalence. However, rapidly emerging mosquito resistance to the chemicals and logistical problems in transporting supplies to remote locations threaten the long-term sustainability of these techniques. Chinaberry (Melia azederach) extracts have been shown to be effective growth-inhibiting larvicides against several insects. Because several active chemicals in the trees' seeds have insecticidal properties, the emergence of resistance is unlikely. Here, we investigate the feasibility of Chinaberry as a locally available, low-cost sustainable insecticide that can aid in controlling malaria. Chinaberry fruits were collected from Asendabo, Ethiopia. The seeds were removed from the fruits, dried and crushed into a powder. From developmental habitats in the same village, Anopheles arabiensis larvae were collected and placed into laboratory containers. Chinaberry seed powder was added to the larval containers at three treatment levels: 5 g m(-2), 10 g m(-2) and 20 g m(-2), with 100 individual larvae in each treatment level and a control. The containers were monitored daily and larvae, pupae and adult mosquitoes were counted. This experimental procedure was replicated three times. Results: Chinaberry seed powder caused an inhibition of emergence of (3% at the 5 g m(-2) treatment level, and 100% inhibition of emergence at the two higher treatment levels. The Chinaberry had a highly statistically significant larvicidal effect at all treatment levels (chi(2) = 184, 184, and 155 for 5 g m(-2), 10 g m(-2) and 20 g m(-2), respectively; p < 0.0001 in all cases). In addition, estimates suggest that sufficient Chinaberry seed exists in Asendabo to treat developmental habitat for the duration of the rainy season and support a field trial. Conclusions: Chinaberry seed is a very potent growth-inhibiting larvicide against the major African malaria vector An. arabiensis. The seed could provide a sustainable additional malaria vector control tool that can be used where the tree is abundant and where An. arabiensis is a dominant vector. Based on these results, a future village-scale field trial using the technique is warranted.
  • Unknown author (2005-06-07
  • Keeton, W. S.; Whitman, A. A.; McGee, G. C.; Goodale, C. L. (Forest Science, 2011
      Managing the contribution of forest ecosystems to global carbon cycles requires accurate predictions of biomass dynamics in relation to stand development. Our study evaluated competing hypotheses regarding late-successional biomass dynamics in northern hardwood-conifer forests using a data set spanning the northeastern United States, including 48 mature and 46 old-growth stands. Continuous data on dominant tree ages were available for 29 of these and were used as an indicator of stand development. Aboveground live biomass was significantly (P < 0.001) different between mature (195 Mg/ha) and old-growth (266 Mg/ha) sites. Aboveground biomass was positively (P < 0.001) and logarithmically correlated with dominant tree age; this held for live trees (r(2) = 0.52), standing dead trees (r(2) = 0.36), total trees (r(2) = 0.63), and downed woody debris (r(2) = 0.24). In a Classification and Regression Tree analysis, stand age class was the strongest predictor of biomass, but ecoregion and percent conifer accounted for similar to 25-33% of intraregional variability. Biomass approached maximum values in stands with dominant tree ages of similar to 350-400 years. Our results support the hypothesis that aboveground biomass can accumulate very late into succession in northern hardwood-conifer forests, recognizing that early declines are also possible in secondary forests as reported previously. Empirical studies suggest a high degree of variability in biomass development pathways and these may differ from theoretical predictions. Primary forest systems, especially those prone to partial disturbances, may have different biomass dynamics compared with those of secondary forests. These differences have important implications for both the quantity and temporal dynamics of carbon storage in old-growth and recovering secondary forests. FOR. SCI 57(6):489-505.
  • Stovall, J. P.; Keeton, W. S.; Kraft, C. E. (Canadian Journal of Forest Research-Revue Canadienne De Recherche Forestiere, 2009
      Late-successional riparian forests often regulate autotrophic microhabitats in low-order streams through shading provided by canopies. However, few studies have linked forest structure with periphyton microhabitat in adjoining streams. Our hypotheses were that (1) the heterogeneous horizontal structure in old-growth forests creates more spatially variable below-canopy light environments compared with mature forests and (2) site-specific light availability over streams correlates with spatial distributions of periphyton microhabitat. We surveyed 15 low-order stream reaches in late-successional northern hardwood-hem lock forests in the Adirondack Mountains of New York, USA. We measured forest structure and the below-canopy light environment at all reaches and the periphyton chlorophyll a concentration on artificial substrates in eight reaches. While stand age was not statistically significant, multivariate models of horizontal forest structure (e.g., gap distribution) and topography showed strong relationships (R(2) > 0.70) with the below-canopy light environment across all late-successional forests. Furthermore, metrics of below-canopy light availability explained a small but statistically significant proportion of the variation in chlorophyll a concentration. This variation in chlorophyll a indicates that complex late-successional riparian forests, both mature and old-growth, create a mosaic of heterotrophic (shaded) and autotrophic (lighted) microhabitats along low-order streams. These results reveal important and previously unrecognized links between stream habitat heterogeneity and the horizontal heterogeneous late-successional forest structure.
  • Wilson, Sandra (2005-06-07
      Leachate from potted chrysanthemum is routinely collected and monitored.

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