Ground cover, root zone management and irrigation system effects on soil mineral N dynamics in a newly established sweet cherry orchard
Citation
CGU-CSSS-CIG-ESSSA-CSAFM Joint Annual Meeting Niagara Falls 2018/06/10 - 2018/06/14
Plain language summary
Ground cover, root zone management and irrigation system have profound effects on soil nitrogen (N) supply in sweet cherry (Prunus avium L.) orchards. In a four year (2014-2017) study, soil mineral N (SMN) concentrations to 30 cm depth in different soil and water management treatments were measured in a newly established cherry orchard on a sandy loam soil in Summerland, BC. Soil treatments include (1) untreated soil (control), (2) fumigation at planting, (3) preplant incorporation of agricultural waste compost (AWC), (4) surface application of bark chip mulch after planting (BM), and (5) combined application of AWC and BM. All soil treatments were imposed on a 1.5 m wide strip centered on the tree row under either microsprinkler or drip irrigation in April 2014. Compost and mulch were applied at 150 and 250 m3/ha orchard area, respectively. Both AWC and BM were reapplied to soil surface in 2016. All treatments were fertigated with 15 g P/tree at bloom and daily for six weeks with total 30 g N/tree. Soil samples were collected in spring and late summer each year and soil mineral N was determined. The interaction among treatments and irrigation system was significant at each sampling date. Soil mineral N (SMN) concentrations averaged across years, sampling date and irrigation in BM and BM+AWC (9.42 mg N/kg) were comparable or lower than control (14.0 mg N/kg), but always were lower than fumigation and AWC (17.1 mg N/kg). The SMN concentrations under BM+AWC treatment (5-10 mg N/kg) were more consistent compared with other treatments (3-36 mg N/kg). Environmental factors associated with year affect the magnitude of SMN, but the differences between treatments persisted. A pulse of SMN was observed in fumigated plots in the first year, but values were similar to AWC in subsequent years. In 2017 (dry summer) higher SMN values were measured in drip compared with microsprinkler irrigation system. In cherry orchards on light-textured soils with low organic matter content, annual fluctuations in precipitation and water management are the main drivers of SMN in top 30 cm.
Abstract
Ground cover, root zone management and irrigation system have profound effects on soil nitrogen (N) supply in sweet cherry (Prunus avium L.) orchards. In a four year (2014-2017) study, soil mineral N (SMN) concentrations to 30 cm depth in different soil and water management treatments were measured in a newly established cherry orchard on a sandy loam soil in Summerland, BC. Soil treatments include (1) untreated soil (control), (2) fumigation at planting, (3) preplant incorporation of agricultural waste compost (AWC), (4) surface application of bark chip mulch after planting (BM), and (5) combined application of AWC and BM. All soil treatments were imposed on a 1.5 m wide strip centered on the tree row under either microsprinkler or drip irrigation in April 2014. Compost and mulch were applied at 150 and 250 m3/ha orchard area, respectively. Both AWC and BM were reapplied to soil surface in 2016. All treatments were fertigated with 15 g P/tree at bloom and daily for six weeks with total 30 g N/tree. Soil samples were collected in spring and late summer each year and soil mineral N was determined. The interaction among treatments and irrigation system was significant at each sampling date. Soil mineral N (SMN) concentrations averaged across years, sampling date and irrigation in BM and BM+AWC (9.42 mg N/kg) were comparable or lower than control (14.0 mg N/kg), but always were lower than fumigation and AWC (17.1 mg N/kg). The SMN concentrations under BM+AWC treatment (5-10 mg N/kg) were more consistent compared with other treatments (3-36 mg N/kg). Environmental factors associated with year affect the magnitude of SMN, but the differences between treatments persisted. A pulse of SMN was observed in fumigated plots in the first year, but values were similar to AWC in subsequent years. In 2017 (dry summer) higher SMN values were measured in drip compared with microsprinkler irrigation system. In cherry orchards on light-textured soils with low organic matter content, annual fluctuations in precipitation and water management are the main drivers of SMN in top 30 cm.