東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Modeling phosphorus environmental th...

Jones, Sara L.

FindBook

Google Book

Amazon

博客來

Modeling phosphorus environmental thresholds on a watershed scale.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Modeling phosphorus environmental thresholds on a watershed scale./
作者:	Jones, Sara L.
面頁冊數:	94 p.
附註:	Source: Masters Abstracts International, Volume: 54-04.
Contained By:	Masters Abstracts International54-04(E).
標題:	Soil sciences. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=1588083
ISBN:	9781321729665

Modeling phosphorus environmental thresholds on a watershed scale.
Jones, Sara L.

Modeling phosphorus environmental thresholds on a watershed scale. - 94 p.

Source: Masters Abstracts International, Volume: 54-04.

Thesis (M.S.)--West Virginia University, 2015.

Anthropogenic eutrophication of surface waterways is a major environmental concern as it leads to the decline of aquatic resources and degradation of water. Phosphorus is the most limiting nutrient in freshwater systems and, therefore, an important factor in the control of eutrophication. Identifying the natural P thresholds in soils using the relationship between soil P and potential P losses can help determine areas with a high risk of P loss to waterways via leaching. Twenty-three sites covering a range of land uses were sampled by the USDA-NRCS in the Potomac Watershed in the northeast United States. Four pedons described and sampled at each site were used in this analysis. Samples from horizons in the plow layer (0 to 15 cm) were analyzed and Mehlich 3 P and water extractable P determined. A threshold in the relationship between CaCl2 P and Mehlich 3 P was identified using segmented linear regression (change point analysis) for each land use type. The change point identified for forest lands was 42 mg P kg-1, and for agricultural lands it was 64 mg P kg-1. For the pooled land uses, the change point was 66 mg P kg-1. The change point relates to the P level in soil above which an increase in soil test P is expected to lead to a large rise in P loss to waterways. Using environmental covariates such as soil pH, parent material, and elevation, a prediction surface was generated to predict Mehlich 3 P and Mehlich 3 P sorption ratio levels using various kriging techniques. The modeled surface can be used by land managers as additional information to help prevent P losses that lead to eutrophication.

ISBN: 9781321729665Subjects--Topical Terms:

2122699
Soil sciences.

Modeling phosphorus environmental thresholds on a watershed scale.
LDR:02461nmm a2200277 4500 001 2078709
005 20161129073846.5
008 170521s2015 ||||||||||||||||| ||eng d
020 $a 9781321729665
035 $a (MiAaPQ)AAI1588083
035 $a AAI1588083
040 $a MiAaPQ $c MiAaPQ
100 1 $a Jones, Sara L. $3 3194313
245 1 0 $a Modeling phosphorus environmental thresholds on a watershed scale.
300 $a 94 p.
500 $a Source: Masters Abstracts International, Volume: 54-04.
500 $a Adviser: James A. Thompson.
502 $a Thesis (M.S.)--West Virginia University, 2015.
520 $a Anthropogenic eutrophication of surface waterways is a major environmental concern as it leads to the decline of aquatic resources and degradation of water. Phosphorus is the most limiting nutrient in freshwater systems and, therefore, an important factor in the control of eutrophication. Identifying the natural P thresholds in soils using the relationship between soil P and potential P losses can help determine areas with a high risk of P loss to waterways via leaching. Twenty-three sites covering a range of land uses were sampled by the USDA-NRCS in the Potomac Watershed in the northeast United States. Four pedons described and sampled at each site were used in this analysis. Samples from horizons in the plow layer (0 to 15 cm) were analyzed and Mehlich 3 P and water extractable P determined. A threshold in the relationship between CaCl2 P and Mehlich 3 P was identified using segmented linear regression (change point analysis) for each land use type. The change point identified for forest lands was 42 mg P kg-1, and for agricultural lands it was 64 mg P kg-1. For the pooled land uses, the change point was 66 mg P kg-1. The change point relates to the P level in soil above which an increase in soil test P is expected to lead to a large rise in P loss to waterways. Using environmental covariates such as soil pH, parent material, and elevation, a prediction surface was generated to predict Mehlich 3 P and Mehlich 3 P sorption ratio levels using various kriging techniques. The modeled surface can be used by land managers as additional information to help prevent P losses that lead to eutrophication.
590 $a School code: 0256.
650 4 $a Soil sciences. $3 2122699
650 4 $a Geochemistry. $3 539092
690 $a 0481
690 $a 0996
710 2 $a West Virginia University. $b Davis College of Argriculture, Natural Resources, & Design. $3 2098241
773 0 $t Masters Abstracts International $g 54-04(E).
790 $a 0256
791 $a M.S.
792 $a 2015
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=1588083