Is returning farmland to forest an effective measure to reduce phosphorus delivery across distinct spatial scales?
J Environ Manage
; 252: 109663, 2019 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-31622793
ABSTRACT
As one typical land use change, the mechanism of returning farmland to forests (RFF) on nonpoint source pollution (NPS) is not clear, especially at multiple spatial scales. In this study, by using the Soil and Water Assessment Tool (SWAT), the changes in several flow-related and NPS-related indicators across several nested catchments were quantified and compared in the Three Gorges Reservoir Region, China. The results indicated that RFF could reduce the total flow and total phosphorus (TP), which are higher in the dry season (41% and 79%, respectively) than in the wet season (21% and 47%, respectively) at the watershed with a total area of 2423.74â¯km2. In comparison, RFF has a larger impact on the baseflow index during the wet season (367.02%) than during the dry season (166.54%). The results also indicated that a spatial scaling effect did exist, while the reduction in TP increased from 24.57% to 48.46% as the drainage area increased from 65.92â¯km2 to 2104.35â¯km2. Specific thresholds of RFF efficiency were also observed (approximately 2000â¯km2 for the study area). It is suggested that other source control measures could supplement RFF by stabilizing the efficiency of RFF across different spatial scales. The results of this study could provide valuable suggestions for land use development and water quality protection, especially for large, complex watersheds.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fósforo
/
Poluentes Químicos da Água
País/Região como assunto:
Asia
Idioma:
En
Revista:
J Environ Manage
Ano de publicação:
2019
Tipo de documento:
Article