CORN-SOYBEAN AND ALTERNATIVE CROPPING SYSTEMS EFFECTS ON NO3-N LEACHING LOSSES IN SUBSURFACE DRAINAGE WATER

In a 4-year study, the biannual crop rotation processing tomato–durum wheat was applied to three cropping systems: (i) an innovative organic coupled with no-tillage (ORG+) where an autumn-sown cover crop was terminated by roller-crimping and then followed by the direct transplantation of processing tomato onto the death-mulch cover; (ii) a traditional organic (ORG) with autumn-sown cover crop that was green manured and followed by processing tomato; and (iii) a conventional integrated low-input (INT) with bare soil during the fall–winter period prior to the processing tomato. N balance, yield and N leaching losses were determined. Innovative cropping techniques such as wheat–faba bean temporary intercropping and the direct transplantation of processing tomato into roll-crimped cover crop biomass were implemented in ORG+; the experiment was aimed at: (i) quantifying the N leaching losses; (ii) assessing the effect of N management on the yield and N utilization; and (iii) comparing the cropping system outputs (yield) in relation to extra-farm N sources (i.e., N coming from organic or synthetic fertilizers acquired from the market) and N losses. The effects of such innovations on important agroecological services such as yield and N recycling were assessed compared to those supplied by the other cropping systems. Independently from the soil management strategy (no till or inversion tillage), cover crops were found to be the key factor for increasing the internal N recycling of the agroecosystems and ORG+ needs a substantial improvement in terms of provisioning services (i.e., yield).

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USING RZWQM TO PREDICT HERBICIDE LEACHING LOSSES IN SUBSURFACE DRAINAGE WATER

Transactions of the ASAE ◽

10.13031/2013.17621 ◽

2004 ◽

Vol 47 (5) ◽

pp. 1415-1426 ◽

Cited By ~ 15

Author(s):

A. Bakhsh ◽

L. Ma ◽

L. R. Ahuja ◽

J. L. Hatfield ◽

R. S. Kanwar

Keyword(s):

Subsurface Drainage ◽

Drainage Water ◽

Leaching Losses

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Water Quality in Organic Systems

Sustainable Agriculture Research ◽

10.5539/sar.v4n3p60 ◽

2015 ◽

Vol 4 (3) ◽

pp. 60 ◽

Cited By ~ 6

Author(s):

Cynthia A. Cambardella ◽

Kathleen Delate ◽

Dan B. Jaynes

Keyword(s):

Water Quality ◽

Water Flow ◽

Cropping Systems ◽

Block Design ◽

Water Flux ◽

Subsurface Drainage ◽

Drainage Water ◽

Nutrient Concentrations ◽

Mineral Fertilization ◽

Organic C

Non-point source contamination is a major water quality concern in the upper Midwestern USA, where plant nutrients, especially NO3-N, are susceptible to leaching due to extensive subsurface draining of the highly productive, but poorly drained, soils found in this region. Environmental impacts associated with intensive mineral fertilization in conventional production have encouraged producers to investigate organic methods. The USDA-ARS Organic Water Quality (OWQ) experiment, established in 2011, compares organic (C-S-O/A-A) and conventional (C-S) crop rotations and an organic pasture (bromegrass, fescue, alfalfa, white clover) system. Thirty fully-instrumented, subsurface-drained plots (30.5 m × 30.5 m) laid out in a randomized block design with 5 field replications, isolate subsurface drainage from each plot and permit comparison of treatment effects on subsurface drainage water flow and nutrient concentrations. Objectives for this study were to quantify growing season subsurface drainage water flow, NO3-N concentrations, and NO3-N loads for conventional and organic grain cropping systems from 2012-2014. Temporal patterns of subsurface drainage water flux were similar for all cropping systems for all years, except for the pasture system in 2012 and subsurface drainage water N concentrations were highest in the conventional C-S system except for the early spring 2012. Subsurface drainage water N loading loss for the entire 3-year period from the conventional C-S system (79.2 kgN ha-1) was nearly twice as much as the N loss from the organic C-S-O/A-A system (39.9 kgN ha-1); the pasture system (16.5 kgN ha-1) lost the least amount of N over the 3 years. Results of this study suggest that organic farming practices, such as the application of composted animal manure and the use of forage legumes and green manures within extended cropping rotations, can improve water quality in Midwestern subsurface-drained landscapes.

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Response of Vertical Migration and Leaching of Nitrogen in Percolation Water of Paddy Fields under Water-Saving Irrigation and Straw Return Conditions

Water ◽

10.3390/w11040868 ◽

2019 ◽

Vol 11 (4) ◽

pp. 868 ◽

Cited By ~ 4

Author(s):

Chengxin Zheng ◽

Zhanyu Zhang ◽

Yunyu Wu ◽

Richwell Mwiya

Keyword(s):

Vertical Migration ◽

Growth Stage ◽

Nitrogen Leaching ◽

Water Saving ◽

Paddy Fields ◽

N Leaching ◽

Leaching Losses ◽

Leaching Loss ◽

Straw Return ◽

Percolation Water

The use of water-saving irrigation techniques has been encouraged in rice fields in response to irrigation water scarcity. Straw return is an important means of straw reuse. However, the environmental impact of this technology, e.g., nitrogen leaching loss, must be further explored. A two-year (2017–2018) experiment was conducted to investigate the vertical migration and leaching of nitrogen in paddy fields under water-saving and straw return conditions. Treatments included traditional flood irrigation (FI) and two water-saving irrigation regimes: rain-catching and controlled irrigation (RC-CI) and drought planting with straw mulching (DP-SM). RC-CI and DP-SM both significantly decreased the irrigation input compared with FI. RC-CI increased the rice yield by 8.23%~12.26%, while DP-SM decreased it by 8.98%~15.24% compared with FI. NH4+-N was the main form of the nitrogen leaching loss in percolation water, occupying 49.06%~50.97% of TN leaching losses. The NH4+-N and TN concentration showed a decreasing trend from top to bottom in soil water of 0~54 cm depth, while the concentration of NO3−-N presented the opposite behavior. The TN and NH4+-N concentrations in percolation water of RC-CI during most of the rice growth stage were the highest among treatments in both years, and DP-SM showed a trend of decreasing TN and NH4+-N concentrations. The NO3−-N concentrations in percolation water showed a regular pattern of DP-SM > RC-CI > FI during most of the rice growth stage. RC-CI and DP-SM remarkably reduced the amount of N leaching losses compared to FI as a result of the significant decrease of percolation water volumes. The tillering and jointing-booting stages were the two critical periods of N leaching (accounted for 74.85%~86.26% of N leaching losses). Great promotion potential of RC-CI and DP-SM exists in the lower reaches of the Yangtze River, China, and DP-SM needs to be further optimized.

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The implications of lag times between nitrate leaching losses and riverine loads for water quality policy

Scientific Reports ◽

10.1038/s41598-021-95302-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

R. W. McDowell ◽

Z. P. Simpson ◽

A. G. Ausseil ◽

Z. Etheridge ◽

R. Law

Keyword(s):

Water Quality ◽

Mean Transit Time ◽

Lag Time ◽

Practice Change ◽

N Leaching ◽

N Losses ◽

Leaching Losses ◽

Nitrate N ◽

The Mean ◽

Lag Times

AbstractUnderstanding the lag time between land management and impacts on riverine nitrate–nitrogen (N) loads is critical to understand when action to mitigate nitrate–N leaching losses from the soil profile may start improving water quality. These lags occur due to leaching of nitrate–N through the subsurface (soil and groundwater). Actions to mitigate nitrate–N losses have been mandated in New Zealand policy to start showing improvements in water quality within five years. We estimated annual rates of nitrate–N leaching and annual nitrate–N loads for 77 river catchments from 1990 to 2018. Lag times between these losses and riverine loads were determined for 34 catchments but could not be determined in other catchments because they exhibited little change in nitrate–N leaching losses or loads. Lag times varied from 1 to 12 years according to factors like catchment size (Strahler stream order and altitude) and slope. For eight catchments where additional isotope and modelling data were available, the mean transit time for surface water at baseflow to pass through the catchment was on average 2.1 years less than, and never greater than, the mean lag time for nitrate–N, inferring our lag time estimates were robust. The median lag time for nitrate–N across the 34 catchments was 4.5 years, meaning that nearly half of these catchments wouldn’t exhibit decreases in nitrate–N because of practice change within the five years outlined in policy.

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