Author: Nicole A. SeltzerPublisher:
ISBN:
Category : Phosphorus
Languages : en
Pages : 200
Book Description
Evaluating Phosphorus Levels in Lake Champlain Using a Landscape-scale Approach
Author: Nicole A. SeltzerPublisher:
ISBN:
Category : Phosphorus
Languages : en
Pages : 200
Book Description
Suitability of Input-output Models for Evaluating the Impact of Phosphorus Loadings to Lake Champlain
Author: John Van BenschotenPublisher:
ISBN:
Category : Champlain, Lake
Languages : en
Pages : 98
Book Description
A Landscape Scale Evaluation of Phosphorus Retention in Wetlands in the LaPlatte River Basin, Vermont, USA
Author: Lisa J. WindhausenPublisher:
ISBN:
Category : Water
Languages : en
Pages : 138
Book Description
The trophic status and phosphorus loadings of Lake Champlain
Author: E B. HensonPublisher:
ISBN:
Category : Champlain, Lake
Languages : en
Pages : 158
Book Description
Lake Champlain: Partnerships and Research in the New Millennium
Author: Tom ManleyPublisher: Springer Science & Business Media
ISBN: 1475740808
Category : Science
Languages : en
Pages : 424
Book Description
This monograph presents the proceedings of the 2002 Spring Symposium sponsored by the Lake Champlain Research Consortium, hosted by the Missisquoi Bay Watershed Corporation. The book examines this common body of water shared by Canada and the US, and summarizes knowledge of the dynamics of this system with a primary focus on land use, water management, and bridging the gap between researchers and the public.
Evaluation of Soil Factors Controlling Phosphorus Concentration in Runoff from Agricultural Soils in the Lake Champlain Basin
Author: Frederick R. MagdoffPublisher:
ISBN:
Category : Agricultural pollution
Languages : en
Pages : 22
Book Description
Links Between Geomorphic Condition, Water Quality, and Phosphorus Loading in Hungerford Brook, Vermont
Author: Dani NewcombPublisher:
ISBN:
Category :
Languages : en
Pages : 182
Book Description
Nonpoint source pollution by phosphorus and sediment is a wide-spread problem across the United States and specifically in Vermont and the Lake Champlain Basin. Best management of nonpoint source loading will likely involve a combination of land use and stream channel modifications, but few studies have comprehensively examined the relative importance of land use, streambank instability, and soil phosphorus. Thus, it is important to understand the associations between these characteristics, as well as their overall, relationship to watershed nutrient loading dynamics. The main objectives of this study were (1) to examine the impacts of land use at the watershed and near-stream scales on total suspended solids (TSS), total phosphorus (TP), and soluble reactive phosphorus (SRP), (2) to explore the links between geomorphic condition and phosphorus and sediment concentrations and loads throughout the watershed and at different spatial scales, and (3) to investigate the importance of soil phosphorus concentrations in stream banks in contributing to the overall phosphorus load. TP, SRP, and TSS samples were collected from eight sites located at tributary junctures and one site at the mouth of Hungerford Brook, a 50 km2 watershed in the Lake Champlain Basin, under storm and baseflow conditions. Rapid geomorphic assessment (RGA) scores, land use, and soil phosphorus concentrations were collected for reaches upstream of sampling locations. Both nested and unnested design multivariate modeling was used to evaluate the importance of characteristics in the individual subwatersheds (unnested) or the entire upstream watershed (nested). SRP, TP, and TSS were predicted as both concentrations and instantaneous loads, using raw quantifications of subwatershed characteristics as well as these same characteristics standardized by the area of agriculture in the subwatershed. Correlation coefficients and principal components analysis were used to select variables that were used in Akaike information criterion (AIC) model selection and stepwise regression. Unnested variables used were agriculture, agriculture in a streamside buffer, proportion of corn, slope, channel degradation, and soil phosphorus. For the nested design, agriculture, agriculture in the buffer, channel aggradation, RGA score, and soil phosphorus concentrations were used. Best fit models were selected based on AICc scores and overall model R2. n ANOVA was also performed on the percent difference between storm flow concentrations and average baseflow concentrations. Results indicate that phosphorus and sediment transport occurs mainly during storm events and concentrations greatly exceed state water quality standards. Concentrations of SRP and TP were significantly lower at the mouth of Hungerford Brook than in upstream subwatersheds, indicating that deposition and storage are occurring in this downstream part of the watershed. SRP concentrations appear to be best explained by agriculture in the riparian buffer, while TP and TSS are influenced by agricultural land use at multiple spatial scales. Agricultural land use was associated with increased stream instability. These findings suggest that additional phosphorus and sediment management, targeted at increasing stream stability and reducing impacts from agriculture, are needed in order to reduce the overall load traveling to Lake Champlain.
Preliminary Evaluation of Progress Toward Lake Champlain Basin Program Phosphorus Reduction Goals
Author: Lake Champlain Basin ProgramPublisher:
ISBN:
Category : Phosphorus
Languages : en
Pages : 46
Book Description
Developing and Assessing Policy Options for Reducing Phosphorus Loading in Lake Champlain
Author: Publisher:
ISBN:
Category : Agricultural pollution
Languages : en
Pages : 131
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.