A study was conducted from 2010 to 2017 to determine the water footprint for producing blueberries in the Entre Ríos province of Argentina. Three cultivars of southern highbush blueberry (hybrid cross of Vacciniu...A study was conducted from 2010 to 2017 to determine the water footprint for producing blueberries in the Entre Ríos province of Argentina. Three cultivars of southern highbush blueberry (hybrid cross of Vaccinium sp.) were evaluated in the study, including “Star”, “Emerald”, and “Snowchaser”. In each case, the plants were irrigated by drip and protected from frost using overhead sprinklers. Water requirements for irrigation and frost protection varied among the cultivars due to differences in the timing of flowering and fruit development. The annual water footprint for fruit production in each cultivar is expressed in units of cubic meters of water used to produce one ton of fresh fruit and ranged from 212 - 578 m<sup>3</sup>∙t<sup>−1</sup> for “Star”, 296 - 985 m<sup>3</sup>∙t<sup>−1</sup> for “Emerald”, and 536 - 4066 m<sup>3</sup>∙t<sup>−1</sup> for “Snowchaser”. “Snowchaser” flowered earlier than the other cultivars and, therefore, needed more water for frost protection. “Star”, on the other hand, ripened the latest among the cultivars and required little to no water for frost protection. Frost protection required a minimum of 30 m<sup>3</sup>∙h<sup>−1</sup> of water per hectare and in addition to drip irrigation was a major component of the water footprint.展开更多
Compared with the use of expensive pressure-compensating drip tapes,installing pressure regulators(PRs)at the inlet of cost-effective non-pressure-compensating drip tapes is obviously a more economical technology to a...Compared with the use of expensive pressure-compensating drip tapes,installing pressure regulators(PRs)at the inlet of cost-effective non-pressure-compensating drip tapes is obviously a more economical technology to achieve precision agriculture.However,most drip lateral PRs may not meet the requirements of the design and use of complex drip irrigation systems(hilly or large-scale systems),and there is seldom research on their application in drip irrigation systems,both restricting the promotion of this precision agriculture technology.In this paper,two types of PRs(A-and B-type)for complex drip irrigation systems are proposed,and compared with two conventional PRs(C-and D-type)under 9 different pressure and flow conditions of the drip irrigation system.The main advantage of A-and B-type PRs over conventional PRs is that their outlet pressures are scarcely affected by inlet pressure and flow.Therefore,A-and B-type PRs not only cope with large submain pressure differences,but also guarantee irrigation uniformity CU up to 90%in drip irrigation systems with different drip-tape lengths(flow range:350-1400 L/h),while CU can be lower than 80%under the same conditions without PRs or using conventional PRs.When designing drip irrigation systems,the use of A-and B-type PRs can allocate greater pressure deviation to the laterals(h_(v2))to increase the lateral laying length,thus further reducing pipeline network investment.Under the requirements of maximum pressure deviation hv≤40%and submain pressure deviation hv1≤20%,the results of h_(v2) with A-,B-,C-,and D-type PRs were 30%-35%,30%-37%,33%-35%,and 21%-27%,respectively.This research provides a device and method that can improve the irrigation uniformity of drip irrigation systems across a wider application range.Based on this research,users can reasonably select the PRs according to different design standards,significantly enhancing the irrigation uniformity of the system in a cost-effective manner.展开更多
文摘A study was conducted from 2010 to 2017 to determine the water footprint for producing blueberries in the Entre Ríos province of Argentina. Three cultivars of southern highbush blueberry (hybrid cross of Vaccinium sp.) were evaluated in the study, including “Star”, “Emerald”, and “Snowchaser”. In each case, the plants were irrigated by drip and protected from frost using overhead sprinklers. Water requirements for irrigation and frost protection varied among the cultivars due to differences in the timing of flowering and fruit development. The annual water footprint for fruit production in each cultivar is expressed in units of cubic meters of water used to produce one ton of fresh fruit and ranged from 212 - 578 m<sup>3</sup>∙t<sup>−1</sup> for “Star”, 296 - 985 m<sup>3</sup>∙t<sup>−1</sup> for “Emerald”, and 536 - 4066 m<sup>3</sup>∙t<sup>−1</sup> for “Snowchaser”. “Snowchaser” flowered earlier than the other cultivars and, therefore, needed more water for frost protection. “Star”, on the other hand, ripened the latest among the cultivars and required little to no water for frost protection. Frost protection required a minimum of 30 m<sup>3</sup>∙h<sup>−1</sup> of water per hectare and in addition to drip irrigation was a major component of the water footprint.
基金financially supported by China Institute of Water Resources and Hydropower Research(Grant No.MK2021J10)China Agriculture Research System of MOF and MARA(Grant No.CARS-03-43)The Open University of China Youth Research Project:Research of the synergistic control mechanism of microirrigation submain and lateral pressure/flow regulator(Grant No.Q23A0009).
文摘Compared with the use of expensive pressure-compensating drip tapes,installing pressure regulators(PRs)at the inlet of cost-effective non-pressure-compensating drip tapes is obviously a more economical technology to achieve precision agriculture.However,most drip lateral PRs may not meet the requirements of the design and use of complex drip irrigation systems(hilly or large-scale systems),and there is seldom research on their application in drip irrigation systems,both restricting the promotion of this precision agriculture technology.In this paper,two types of PRs(A-and B-type)for complex drip irrigation systems are proposed,and compared with two conventional PRs(C-and D-type)under 9 different pressure and flow conditions of the drip irrigation system.The main advantage of A-and B-type PRs over conventional PRs is that their outlet pressures are scarcely affected by inlet pressure and flow.Therefore,A-and B-type PRs not only cope with large submain pressure differences,but also guarantee irrigation uniformity CU up to 90%in drip irrigation systems with different drip-tape lengths(flow range:350-1400 L/h),while CU can be lower than 80%under the same conditions without PRs or using conventional PRs.When designing drip irrigation systems,the use of A-and B-type PRs can allocate greater pressure deviation to the laterals(h_(v2))to increase the lateral laying length,thus further reducing pipeline network investment.Under the requirements of maximum pressure deviation hv≤40%and submain pressure deviation hv1≤20%,the results of h_(v2) with A-,B-,C-,and D-type PRs were 30%-35%,30%-37%,33%-35%,and 21%-27%,respectively.This research provides a device and method that can improve the irrigation uniformity of drip irrigation systems across a wider application range.Based on this research,users can reasonably select the PRs according to different design standards,significantly enhancing the irrigation uniformity of the system in a cost-effective manner.
