Reclaimed water (RW) applied in drip irrigation systems could be a solution to cope with the challenges of limited freshwater resources. Biofilm growth in irrigation systems is an unavoidable issue when using RW. To date, strong chemical bactericides mostly dominate the commercial market in controlling biofilms. However, recently scientists have been concerned about their real efficacy and environmental risks. This study assesses a low-concentration microbial antagonist (i.e., Bacillus amyloliquefaciens inoculums, BAI) intermittently injected into the systems to mitigate biofilm formation in three types of drip emitters using two kinds of treated RW. The results indicated that the application of BAI significantly (p < .05) mitigated the microbial biomass within biofilms when compared with the control groups (no-BAI). In addition, BAI reduced the contents of extracellular polysaccharides and proteins of biofilms, which decreased the total biomass in BAI treatments by 44.9%–73.8%. Consequently, BAI effectively improved the emitter performances and increased the discharge variation rate by 31.9%–44.3%. These findings might provide a new perspective to control biofouling when applying RW in irrigation systems, with potential implications for sustainable water management in agricultural production.

Presented at: 73rd IEC Meeting, Adelaide, Australia, 2022

Within the Chinese Loess Plateau, water resources are scarce, and irrigation ef?ciency is a challenging issue. Traditional surface drip irrigation (SDI) methods have failed to improve irrigation ef?ciency and reduce surface evaporation in the region. An easy-to-install and practicable root-zone injection irrigation (RII) method, with a low risk of emitter clogging and which uses subsurface in?ltration-promoting apparatuses (SIPA) to deliver water directly to the root zone, was designed and tested in an apple orchard over 3 years in northern Shaanxi, China. In the 0–0.6 m soil layer (where the apple roots are concentrated), the RII method produced consistently higher soil water content than the SDI method over all three growing seasons. The soil water content was consistently higher than 60% of ?eld capacity, thus meeting the water requirements of fruit-bearing apple trees. In addition, the RII method alleviated soil desiccation, signi?cantly increased apple yields and improved fruit quality compared with the SDI method using the same volume of irrigation water. Both irrigation ef?ciency and water-use ef?ciency were improved with the RII method. These results provide a theoretical basis for the utilisation of the RII irrigation method in apple orchards in semi-arid regions, which may improve water conservation and the sustainability of apple production.

Keywords: Root-zone injection irrigation, subsurface, emitter clogging, surface drip irrigation

Presented at: 72nd IEC Meeting 2021, Marrakesh, Morocco

Keywords: Climate, agriculture, river

Presented at: 71st IEC Meeting 2020, New Delhi, India

Keywords: Inter-basin; multi-reservoir operation; early risk warning system; mixed Copula function; early warning signals; uncertain factor; emergency water shortage measures

Presented at: 70th IEC Meeting 2019, Bali, Indonesia

Keywords: Fertigation; drainage water of fish farms; yield production; SALTMED

Presented at: 69th IEC Meeting 2018, Saskatoon, Canada

Keywords: ANFIS; groundwater level; salinity; SVM; waterlogging

Presented at: 69th IEC Meeting 2018, Saskatoon, Canada

Keywords: Irrigation scheduling; soil water tension-based irrigation; crop coefcient; crop growth modelling; multi-objective optimization; white cabbage

Presented at: 68th IEC Meeting 2017, Mexico City, Mexico,

Keywords: Groundwater irrigation; energy; greenhouse gas emissions; water depletion

Presented at: 67th IEC Meeting 2016, Chiang Mai, Thailand

Keywords: Water–food–energy nexus; green economy; water efficiency; energy efficiency; food waste; virtual water; water footprint; integrated water resource management; supply chain; environment; ecology

Presented at: 66th IEC Meeting 2015, Montpellier, France

Keywords: Multi-sector water sharing; stakeholder collaboration; social and economic factors in water management

Presented at: 65th IEC Meeting 2014, Gwangju, Rep. of Korea

Keywords: Land use planning; water productivity; remote sensing; economic analysis; water indicators

Presented at: 64th IEC Meeting 2013, Mardin, Turkey

Keywords: Irrigation mosaics; mosaics; irrigation impact; irrigation patches

Presented at: 63rd IEC Meeting 2012, Adelaide, Australia

Keywords: water leak detection; airborne remote sensing; multispectral imaging; irrigation distribution network; canal leakage; field reconnaissance; thermal imagery; normalized difference vegetation index

Presented at: 62nd IEC Meeting 2011, Tehran, Iran

Keywords: Drainage; irrigation; salinity; perception; problem tree; oasis; Tunisia

Presented at: 61st IEC Meeting 2010, Yogyakarta, Indonesia

Keywords: BHIWA model; water budgets; scenarios development; water situation indicators

Presented at: 60th IEC Meeting 2009, New Delhi, India

Keywords: systemlevel water saving; system dynamic model; production and profit functions; China

Presented at: 59th IEC Meeting 2008, Lahore, Pakistan

Keywords: Drainage; drain depth; waterlogging; salinity

Presented at: 59th IEC Meeting 2008, Lahore, Pakistan

Keywords: irrigated agriculture; user charges; market trades; water user associations; socioeconomic transformation; South Africa

Presented at: 58th IEC Meeting 2007, Sacramento, USA

Keywords: Farmers' participation; land leveling; crop irrigation scheduling; water saving; wheat yield

Presented at: 57th IE Meeting 2006, Kuala Lumpur, Malaysia