Author: United States. Soil Conservation ServicePublisher:
ISBN:
Category :
Languages : en
Pages : 66
Book Description
Computational Methods for Assessing Phosphorus Losses in the Vermont Agricultural Runoff Study
Author: United States. Soil Conservation ServicePublisher:
ISBN:
Category :
Languages : en
Pages : 66
Book Description
Understanding and Mitigating Phosphorus Losses in the Vermont Lake Champlain Basin at the Watershed and Field Scale in a Changing Climate
Author: George Harrison MyersPublisher:
ISBN:
Category : Champlain, Lake, Watershed
Languages : en
Pages : 0
Book Description
Alteration of global nitrogen (N) and phosphorus (P) cycles to support livestock and crop production is the most significant driver of global nutrient surpluses. Losses of excess nutrients to the environment contribute to eutrophication of aquatic systems, leading to harmful algal blooms (HABs), hypoxia, and fish kills. Livestock and dairy production are directly linked to the acceleration of eutrophication via nutrient losses from animal manure. Lake Champlain has been experiencing HABs since the 1970s, and a total maximum daily load (TMDL) is in place to reduce P loading to the lake, with much of the reduction in P load being required to come from the agricultural sector. It is critical to understand nutrient movement and the impact of a changing regional climate in manure-based agricultural watersheds, as dairy farming is the primary agricultural sector in Vermont. Additionally, studying agricultural management practices to mitigate P losses is imperative to meet the target P load reductions set forth by the TMDL. The first portion of this thesis analyzes seasonal differences in nutrient movement in two manure-based agricultural watersheds in the Vermont Lake Champlain Basin (VT LCB) with varying extent of agricultural land use. The results show that the spring and summer had the smallest seasonal loads of total P (TP) and dissolved P (DP) in runoff. The smaller summer P loads appear to be related to periods of drought, while the smaller P loads in the spring are likely related to less manure P built up in the watershed that could be transported to surface waters. Approximately 40% of the cumulative TP load and 43% of the cumulative DP load was discharged from the watersheds in the fall. The increased fall TP and DP loads were likely due to the application of manure across the watersheds during this period. The data suggest that soil erosion is relatively less dominant as a driver of watershed P discharge during times when manure was available for transport post-application (e.g., fall and summer), and more closely linked to watershed P loss during times when less new manure was available (e.g., spring). The results suggest better management of manure application rates and timing as well as increased implementation of agricultural management practices are needed to address increased P transport throughout the year, and especially during the fall. The second portion of this thesis assesses the efficacy of edge-of-field (EOF) iron-based filters for P removal. In-field agricultural management practices such as no-till management and cover cropping target reductions in TP, but do not effectively address DP. EOF filters are a promising management practice for reducing DP losses. Storm runoff at the inlet and outlet of one subsurface and two surface EOF filters was monitored for 10 months. The subsurface filter proved very effective for soluble reactive P (SRP) and TP removal, removing 99% of cumulative SRP load and 91% of TP load from monitored events. The surface filters had varied results, with the east surface filter removing 19% of SRP load and 72% of TP load, and the west surface filter removing 52% of SRP load and having no effect on TP load. The findings highlight the importance of filter sizing and design to minimize the impact of sediment loading and preferential flow pathways on surface EOF filter performance. The study provides early evidence that tile drain filters are a highly effective management strategy for mitigating SRP and TP losses from agricultural fields.
An Analysis of Agricultural Decision-Making for Phosphorus Runoff Reduction in the State of Vermont
Author: Bethany Elizabeth BrownPublisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 122
Book Description
Eutrophication, stimulated by phosphorous (P) runoff from landscapes, compromises water quality and can have long-term impacts on the aesthetics, recreation, property values, and drinkability of bodies of water around the world. In the State of Vermont, efforts are underway to control the amount of P entering Lake Champlain per standards set forth in the Federal Clean Water Act. Agriculture has been identified as a major contributor to excess P in the waterways and will be managed according to Act 64, the Vermont Water Quality Act. The studies presented in this paper will introduce two independent methodologies proposed to aid in evaluating the farmer's willingness to implement pro-environmental practices, (1) determining farmer values towards implementation of best management practices to inform policy, and (2) creating a multifunctional sustainability prioritization scheme for dissemination of Clean Water Fund resources. The Vermont Water Quality Act proposes Required Agricultural Practices (RAP) for agriculture in the State with a limited understanding of what the farming community desires from such a policy. This paper's first article titled, "Determining Farmer Values for Implementing Pro-Environmental Practices," analyzes twenty-four farmers and their associated values towards adopting pro-environmental practices for improved water quality. A hierarchical cluster analysis was used to segment farmers according to their adoption of best management practices on their farms. Further, a one-way analysis of variance (ANOVA) was conducted using dependent functional (quality), functional (price), and emotional, social, conditional, and epistemic variables to understand the variance between the segments. The results from this analysis illuminate farmer values. This information can be used to inform water quality policy, ecosystem service payments, communication strategy, and funding dissemination. The Clean Water Fund was created to support the implementation of water quality initiatives in various sectors throughout the State of Vermont. The resources within the fund are limited; therefore careful prioritization of farms for outreach is essential. In the article titled, Prioritizing Farms for Subsidies: A "Multifunctional Approach," a prioritization methodology is presented using theory from the sustainable multifunctional agriculture literature. The sample includes vegetable, vegetable and meat, meat, and maple producers within the State. The diverse production types included in this study reflects the non-discriminatory-relating to production types-policies in Act 64. The study is limited by the exclusion of the dairy sector. Geographic Information Systems (GIS) software was used to map environmental practices on twelve farm landscapes to generate a spatial representation of environmental stewardship that was then translated into an environmental score. This environmental score was combined with social and economic data to prioritize farms based upon their multifunctional sustainability. This ranking methodology may be useful for the State of Vermont in determining the prioritization of Clean Water Fund resources using farm sustainability measurements.
Phosphorus Reduction and Farm Income
Author: Ralph E. HeimlichProceedings of the Canadian Hydrology Symposium No. 19, 1992
Author: Selected Water Resources Abstracts
Author: Scientific and Technical Aerospace Reports
Author: Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 758
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Selected Water Resources Abstracts
Author: Caves and Karst Across Time
Author: Yongli GaoPublisher: Geological Society of America
ISBN: 081372516X
Category : Science
Languages : en
Pages : 318
Book Description
"Knowledge and understanding of cave and karst systems have evolved dramatically since the creation of the Geological Society of America in 1888. This book, which came out of a session during GSA's 2013 Annual Meeting, highlights the changes in the study and application of cave and karst systems since GSA's origin, while looking ahead to future advancements"--
Author: