The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the... more The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the field is often quite different from that obtained in experimental stations. We developed an approach to explain the actual irrigation performance of drip irrigation systems by linking measured performances to farmers’ irrigation practices, and these practices to the underlying logic of farmers who operate these systems. This approach was applied to 22 farms in Morocco. Four sets of variables helped explain the gap between the actual irrigation performance and the performance obtained in experimental conditions: (1) farmers have agro-economic motivations or want to improve their social status, and for them, irrigation performance is at best an intermediate objective. (2) Irrigation performance is not a static value, but a rapidly evolving process, related to the (perceived) ability of farmers to change irrigation practices and renew irrigation equipment, but also to farmers’ aspirations. (3) The social network of farmers, supporting the introduction and use of drip irrigation, determines how farmers may share experience, information and know-how related to drip irrigation. (4) Today, there is no social pressure to irrigate carefully to save water; only the state explicitly links the use of drip irrigation to saving water. Making the drip user visible in research and policy studies would lead to more realistic assessments of irrigation performance and draw the attention of policy makers to the actual conditions in which drip irrigation is used, and as a consequence help incorporate ‘saving water’ as an objective for drip irrigation users.
The effects of climate change on food security have been unfavorable, particularly in the area of... more The effects of climate change on food security have been unfavorable, particularly in the area of Murcia where there is a water shortage. To satisfy crop needs, farmers combine several irrigation water sources, such as brackish groundwater, desalinated water, reclaimed water, and desalinated water. Good agricultural and irrigation practices are essential for preventing soil salinization and production losses, and remote sensing might be used to evaluate these practices. This research, performed in an experimental field under greenhouse conditions and in an open-air commercial lettuce field irrigated with non-conventional water sources, determined that the Salinity Index (SI) applied to bare soil is a useful spectral index, providing an R2 range of 0.40 to 0.83. The other metric used to the bare soil, the Normalized Difference Salinity Index (NDSI), exhibited poor correlations, with R2 values as high as 0.49. Moreover, the thermal camera did not operate well within the greenhouse, bu...
The study analysed the impact of a farm dam on the river flow in the Limpopo River basin. Two met... more The study analysed the impact of a farm dam on the river flow in the Limpopo River basin. Two methods are used to calculate the water inflow: one uses the runoff component from the catchment water balance; the other uses the drainage output of the SIMFLOW model. The impact on the flow in a sub-catchment with and without the presence of a farm dam, has been analysed. Different farm dam storage capacities and infiltration rates of the soil were considered. In general, the change in natural flow is decreasing when the farm dam capacity becomes higher. On the other hand, the Remaining Natural Flow is increasing when the catchment area becomes larger. The Crop Water Availability was expressed as the relative difference between the crop water requirements and the amount of water supplied by precipitation and irrigation from the farm dam. For a given storage capacity of the farm dam the change in natural flow is calculated when the farm dam covers 90% of the potential evapotranspiration of...
ABSTRACT Drip irrigation figures prominently in water policy debates as a possible solution to wa... more ABSTRACT Drip irrigation figures prominently in water policy debates as a possible solution to water scarcity problems, based on the assertion that it will improve water use efficiencies. We use this article to carefully trace the scientific basis of this assertion. Through a systematic review of the literature, we show that the term efficiency means different things to different people, and can refer to different elements in the water balance. Most articles claim that drip irrigation is irrigation water use efficient and crop water use efficient, but different studies use different definitions of these terms. In addition, measured efficiency gains not only refer to different capacities of the technology, but are also based on very specific boundary (scale) assumptions. We conclude that efficiency gains from drip irrigation will only be achieved under narrowly defined operational conditions, and just apply to very specific spatial and temporal scales. Hence, and unlike what generalized statements in policy documents and the overall enthusiasm for drip as a water saving tool suggest, expectations of increased water efficiencies associated with drip will only be realized, and are just realizable, in very specific circumstances.
Drip irrigation is widely promoted in Spain to increase agricultural production and to save water... more Drip irrigation is widely promoted in Spain to increase agricultural production and to save water. In the Cànyoles watershed, Valencia, we analysed the consequences of change from surface irrigation to drip irrigation over the past 25 years. There were a number of transformations resulting from, or accelerated by, this change including the 1) intensification of well construction causing a redistribution in access to groundwater, water shortages and a lowering of the groundwater table; 2) expansion of irrigation into former rain-dependent uphill areas resulting in increased water use; 3) shift to higher-value monoculture fruit crops, but with associated higher crop water requirements; 4) increased electrical energy consumption and higher costs due to groundwater pumping; and 5) loss of cultural heritage as wells have replaced traditional surface irrigation infrastructure that originated in the Middle Ages. Consequently, the authors argue that transitioning from surface irrigation to ...
Low cost micro drip kit is being touted in South Asia and other developing countries by Internati... more Low cost micro drip kit is being touted in South Asia and other developing countries by International Development Enterprises (iDE) with an objective to empower ‘poor’ smallholder farmers to invest their way out of poverty. ‘Success’ stories are told of the technology being adopted by farmers in India. With this assumption, the development of drip was replicated in Zambia without the much anticipated success. Thousands of low-cost drip kits were sold to targeted farmers but, after a few years, only few were still functional on farmers’ fields. Most of the farmers either did not use the technology or abandoned it after using it for a brief period of time. A number of social, economic, physical, technical as well as institutional challenges can explain this. This study reviewed conditions that characterized the success and challenges of drip in India and Zambia respectively, focusing on the technical configuration of drip systems in the latter. The authors argue that the drip technolo...
Este trabajo no podria haberse realizado sin el apoyo economico del proyecto de investigacion ‘Us... more Este trabajo no podria haberse realizado sin el apoyo economico del proyecto de investigacion ‘Use of Advanced information technologies for Site-Specific management of Irrigation and SaliniTy with degraded water’ (ASSIST) financiado por la Fundacion SENECA en el Programa Regional "SAAVEDRA FAJARDO", y el Proyecto SHui, cofinanciado por el Proyecto de la Union Europea GA 773903 y el MOST de China.
Drip irrigation has long been promoted as a promising way to meet today’s world water, food and p... more Drip irrigation has long been promoted as a promising way to meet today’s world water, food and poverty challenges. In most scientific
and policy documents, drip irrigation is framed as a technological innovation with definitive intrinsic characteristics—that of
efficiency, productivity andmodernity. Based on evidence from North and West Africa aswell as South Asia, we show that there are
multiple actors involved in shaping this imagery, the legitimacy of which largely stems from an engineering perspective that treats
technology and potential as ‘truths’ that exist independently of the context of use. Rather than ascribing the advent of drip irrigation
as a successful technology to intrinsic technical features, this paper proposes to see it as grounded in the ability drip irrigation has to
lend itself to multiple contexts and discourses that articulate desirable futures. We thus adopt a view of technology whereby the
‘real’ (i.e. the drip irrigation hardware) acquires its characteristics only through, and within, the network of institutions, discourses
and practices that enact it. Such a perspective sheds light on the iterative alignments that take place between hardware and context
and treat these as inherent features, rather than externalities, of the innovation process.
The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the... more The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the field is often quite different from that obtained in experimental stations. We developed an approach to explain the actual irrigation performance of drip irrigation systems by linking measured performances to farmers’ irrigation practices, and these practices to the underlying logic of farmers who operate these systems. This approach was applied to 22 farms in Morocco. Four sets of variables helped explain the gap between the actual irrigation performance and the performance obtained in experimental conditions: (1) farmers have agro-economic motivations or want to improve their social status, and for them, irrigation performance is at best an intermediate objective. (2) Irrigation performance is not a static value, but a rapidly evolving process, related to the (perceived) ability of farmers to change irrigation practices and renew irrigation equipment, but also to farmers’ aspirations. (3) The social network of farmers, supporting the introduction and use of drip irrigation, determines how farmers may share experience, information and know-how related to drip irrigation. (4) Today, there is no social pressure to irrigate carefully to save water; only the state explicitly links the use of drip irrigation to saving water. Making the drip user visible in research and policy studies would lead to more realistic assessments of irrigation performance and draw the attention of policy makers to the actual conditions in which drip irrigation is used, and as a consequence help incorporate ‘saving water’ as an objective for drip irrigation users.
The effects of climate change on food security have been unfavorable, particularly in the area of... more The effects of climate change on food security have been unfavorable, particularly in the area of Murcia where there is a water shortage. To satisfy crop needs, farmers combine several irrigation water sources, such as brackish groundwater, desalinated water, reclaimed water, and desalinated water. Good agricultural and irrigation practices are essential for preventing soil salinization and production losses, and remote sensing might be used to evaluate these practices. This research, performed in an experimental field under greenhouse conditions and in an open-air commercial lettuce field irrigated with non-conventional water sources, determined that the Salinity Index (SI) applied to bare soil is a useful spectral index, providing an R2 range of 0.40 to 0.83. The other metric used to the bare soil, the Normalized Difference Salinity Index (NDSI), exhibited poor correlations, with R2 values as high as 0.49. Moreover, the thermal camera did not operate well within the greenhouse, bu...
The study analysed the impact of a farm dam on the river flow in the Limpopo River basin. Two met... more The study analysed the impact of a farm dam on the river flow in the Limpopo River basin. Two methods are used to calculate the water inflow: one uses the runoff component from the catchment water balance; the other uses the drainage output of the SIMFLOW model. The impact on the flow in a sub-catchment with and without the presence of a farm dam, has been analysed. Different farm dam storage capacities and infiltration rates of the soil were considered. In general, the change in natural flow is decreasing when the farm dam capacity becomes higher. On the other hand, the Remaining Natural Flow is increasing when the catchment area becomes larger. The Crop Water Availability was expressed as the relative difference between the crop water requirements and the amount of water supplied by precipitation and irrigation from the farm dam. For a given storage capacity of the farm dam the change in natural flow is calculated when the farm dam covers 90% of the potential evapotranspiration of...
ABSTRACT Drip irrigation figures prominently in water policy debates as a possible solution to wa... more ABSTRACT Drip irrigation figures prominently in water policy debates as a possible solution to water scarcity problems, based on the assertion that it will improve water use efficiencies. We use this article to carefully trace the scientific basis of this assertion. Through a systematic review of the literature, we show that the term efficiency means different things to different people, and can refer to different elements in the water balance. Most articles claim that drip irrigation is irrigation water use efficient and crop water use efficient, but different studies use different definitions of these terms. In addition, measured efficiency gains not only refer to different capacities of the technology, but are also based on very specific boundary (scale) assumptions. We conclude that efficiency gains from drip irrigation will only be achieved under narrowly defined operational conditions, and just apply to very specific spatial and temporal scales. Hence, and unlike what generalized statements in policy documents and the overall enthusiasm for drip as a water saving tool suggest, expectations of increased water efficiencies associated with drip will only be realized, and are just realizable, in very specific circumstances.
Drip irrigation is widely promoted in Spain to increase agricultural production and to save water... more Drip irrigation is widely promoted in Spain to increase agricultural production and to save water. In the Cànyoles watershed, Valencia, we analysed the consequences of change from surface irrigation to drip irrigation over the past 25 years. There were a number of transformations resulting from, or accelerated by, this change including the 1) intensification of well construction causing a redistribution in access to groundwater, water shortages and a lowering of the groundwater table; 2) expansion of irrigation into former rain-dependent uphill areas resulting in increased water use; 3) shift to higher-value monoculture fruit crops, but with associated higher crop water requirements; 4) increased electrical energy consumption and higher costs due to groundwater pumping; and 5) loss of cultural heritage as wells have replaced traditional surface irrigation infrastructure that originated in the Middle Ages. Consequently, the authors argue that transitioning from surface irrigation to ...
Low cost micro drip kit is being touted in South Asia and other developing countries by Internati... more Low cost micro drip kit is being touted in South Asia and other developing countries by International Development Enterprises (iDE) with an objective to empower ‘poor’ smallholder farmers to invest their way out of poverty. ‘Success’ stories are told of the technology being adopted by farmers in India. With this assumption, the development of drip was replicated in Zambia without the much anticipated success. Thousands of low-cost drip kits were sold to targeted farmers but, after a few years, only few were still functional on farmers’ fields. Most of the farmers either did not use the technology or abandoned it after using it for a brief period of time. A number of social, economic, physical, technical as well as institutional challenges can explain this. This study reviewed conditions that characterized the success and challenges of drip in India and Zambia respectively, focusing on the technical configuration of drip systems in the latter. The authors argue that the drip technolo...
Este trabajo no podria haberse realizado sin el apoyo economico del proyecto de investigacion ‘Us... more Este trabajo no podria haberse realizado sin el apoyo economico del proyecto de investigacion ‘Use of Advanced information technologies for Site-Specific management of Irrigation and SaliniTy with degraded water’ (ASSIST) financiado por la Fundacion SENECA en el Programa Regional "SAAVEDRA FAJARDO", y el Proyecto SHui, cofinanciado por el Proyecto de la Union Europea GA 773903 y el MOST de China.
Drip irrigation has long been promoted as a promising way to meet today’s world water, food and p... more Drip irrigation has long been promoted as a promising way to meet today’s world water, food and poverty challenges. In most scientific
and policy documents, drip irrigation is framed as a technological innovation with definitive intrinsic characteristics—that of
efficiency, productivity andmodernity. Based on evidence from North and West Africa aswell as South Asia, we show that there are
multiple actors involved in shaping this imagery, the legitimacy of which largely stems from an engineering perspective that treats
technology and potential as ‘truths’ that exist independently of the context of use. Rather than ascribing the advent of drip irrigation
as a successful technology to intrinsic technical features, this paper proposes to see it as grounded in the ability drip irrigation has to
lend itself to multiple contexts and discourses that articulate desirable futures. We thus adopt a view of technology whereby the
‘real’ (i.e. the drip irrigation hardware) acquires its characteristics only through, and within, the network of institutions, discourses
and practices that enact it. Such a perspective sheds light on the iterative alignments that take place between hardware and context
and treat these as inherent features, rather than externalities, of the innovation process.
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Papers by Harm Boesveld
and policy documents, drip irrigation is framed as a technological innovation with definitive intrinsic characteristics—that of
efficiency, productivity andmodernity. Based on evidence from North and West Africa aswell as South Asia, we show that there are
multiple actors involved in shaping this imagery, the legitimacy of which largely stems from an engineering perspective that treats
technology and potential as ‘truths’ that exist independently of the context of use. Rather than ascribing the advent of drip irrigation
as a successful technology to intrinsic technical features, this paper proposes to see it as grounded in the ability drip irrigation has to
lend itself to multiple contexts and discourses that articulate desirable futures. We thus adopt a view of technology whereby the
‘real’ (i.e. the drip irrigation hardware) acquires its characteristics only through, and within, the network of institutions, discourses
and practices that enact it. Such a perspective sheds light on the iterative alignments that take place between hardware and context
and treat these as inherent features, rather than externalities, of the innovation process.
and policy documents, drip irrigation is framed as a technological innovation with definitive intrinsic characteristics—that of
efficiency, productivity andmodernity. Based on evidence from North and West Africa aswell as South Asia, we show that there are
multiple actors involved in shaping this imagery, the legitimacy of which largely stems from an engineering perspective that treats
technology and potential as ‘truths’ that exist independently of the context of use. Rather than ascribing the advent of drip irrigation
as a successful technology to intrinsic technical features, this paper proposes to see it as grounded in the ability drip irrigation has to
lend itself to multiple contexts and discourses that articulate desirable futures. We thus adopt a view of technology whereby the
‘real’ (i.e. the drip irrigation hardware) acquires its characteristics only through, and within, the network of institutions, discourses
and practices that enact it. Such a perspective sheds light on the iterative alignments that take place between hardware and context
and treat these as inherent features, rather than externalities, of the innovation process.