A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows
When urban areas expand without concomitant increases in wastewater treatment capacity, vast quantities of wastewater are released to surface waters with little or no treatment. Downstream of many urban areas are large areas of irrigated croplands reliant on these same surface water sources. Case st...
| Autores principales: | , , , |
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| Formato: | Journal Article |
| Lenguaje: | Inglés |
| Publicado: |
IOP Publishing
2017
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| Materias: | |
| Acceso en línea: | https://hdl.handle.net/10568/82641 |
| _version_ | 1855525014491627520 |
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| author | Thebo, Anne Louise Drechsel, Pay Lambin, Eric Nelson, Kara |
| author_browse | Drechsel, Pay Lambin, Eric Nelson, Kara Thebo, Anne Louise |
| author_facet | Thebo, Anne Louise Drechsel, Pay Lambin, Eric Nelson, Kara |
| author_sort | Thebo, Anne Louise |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | When urban areas expand without concomitant increases in wastewater treatment capacity, vast quantities of wastewater are released to surface waters with little or no treatment. Downstream of many urban areas are large areas of irrigated croplands reliant on these same surface water sources. Case studies document the widespread use of untreated wastewater in irrigated agriculture, but due to the practical and political challenges of conducting a true census of this practice, its global extent is not well known except where reuse has been planned. This study used GIS-based modeling methods to develop the first spatially-explicit estimate of the global extent of irrigated croplands influenced by urban wastewater flows, including indirect wastewater use. These croplands were further classified by their likelihood of using poor quality water based on the spatial proximity of croplands to urban areas, urban wastewater return flow ratios, and proportion of wastewater treated. This study found that 65% (35.9 Mha) of downstream irrigated croplands were located in catchments with high levels of dependence on urban wastewater flows. These same catchments were home to 1.37 billion urban residents. Of these croplands, 29.3 Mha were located in countries with low levels of wastewater treatment and home to 885 million urban residents. These figures provide insight into the key role that water reuse plays in meeting the water and food needs of people around the world, and the need to invest in wastewater treatment to protect public health. |
| format | Journal Article |
| id | CGSpace82641 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2017 |
| publishDateRange | 2017 |
| publishDateSort | 2017 |
| publisher | IOP Publishing |
| publisherStr | IOP Publishing |
| record_format | dspace |
| spelling | CGSpace826412025-11-12T05:10:18Z A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows Thebo, Anne Louise Drechsel, Pay Lambin, Eric Nelson, Kara indirect water reuse water quality gis spatial analysis return flow ratio urban sanitation wastewater treatment irrigated land farmland urban wastes water reuse sanitation surface water irrigated farming downstream catchment areas public health case studies When urban areas expand without concomitant increases in wastewater treatment capacity, vast quantities of wastewater are released to surface waters with little or no treatment. Downstream of many urban areas are large areas of irrigated croplands reliant on these same surface water sources. Case studies document the widespread use of untreated wastewater in irrigated agriculture, but due to the practical and political challenges of conducting a true census of this practice, its global extent is not well known except where reuse has been planned. This study used GIS-based modeling methods to develop the first spatially-explicit estimate of the global extent of irrigated croplands influenced by urban wastewater flows, including indirect wastewater use. These croplands were further classified by their likelihood of using poor quality water based on the spatial proximity of croplands to urban areas, urban wastewater return flow ratios, and proportion of wastewater treated. This study found that 65% (35.9 Mha) of downstream irrigated croplands were located in catchments with high levels of dependence on urban wastewater flows. These same catchments were home to 1.37 billion urban residents. Of these croplands, 29.3 Mha were located in countries with low levels of wastewater treatment and home to 885 million urban residents. These figures provide insight into the key role that water reuse plays in meeting the water and food needs of people around the world, and the need to invest in wastewater treatment to protect public health. 2017-07-01 2017-07-04T15:36:00Z 2017-07-04T15:36:00Z Journal Article https://hdl.handle.net/10568/82641 en Open Access application/pdf IOP Publishing Thebo, A.L.; Drechsel, P.; Lambin, E.; Nelson, K. 2017. A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows. Environmental Research Letters.12(7):20p. |
| spellingShingle | indirect water reuse water quality gis spatial analysis return flow ratio urban sanitation wastewater treatment irrigated land farmland urban wastes water reuse sanitation surface water irrigated farming downstream catchment areas public health case studies Thebo, Anne Louise Drechsel, Pay Lambin, Eric Nelson, Kara A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows |
| title | A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows |
| title_full | A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows |
| title_fullStr | A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows |
| title_full_unstemmed | A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows |
| title_short | A global, spatially-explicit assessment of irrigated croplands influenced by urban wastewater flows |
| title_sort | global spatially explicit assessment of irrigated croplands influenced by urban wastewater flows |
| topic | indirect water reuse water quality gis spatial analysis return flow ratio urban sanitation wastewater treatment irrigated land farmland urban wastes water reuse sanitation surface water irrigated farming downstream catchment areas public health case studies |
| url | https://hdl.handle.net/10568/82641 |
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