Spatial and temporal variability of Mehlich-1 extractable Fe, Mn and Zn over a rice field as a function of lime amendment

Abstract

This study compares the effect of lime additions on the spatial variability of Fe, Mn and Zn extracted by Mehlich-1 during three different growth stages from an acid paddy soil, a Typic Plintacualf, in Corrientes, Argentina. Field trials were set up involving three treatments: control, without lime addition, plus two different dolomite doses of 625 and 1250 kg ha -1 . Soil was sampled first before sowing in aerobic conditions and then two more times in anaerobic conditions, i.e. by bunch formation and flowering. Ninety-six samples per plot were taken per lime treatment and sampling period, using a nested sampling strategy. Liming significantly increased extractable Fe and Mn, but decreased extractable Zn. The spatial variability of the studied soil properties was assessed using semivariogram analysis and examination of kriging maps. Models were fitted to experimental semivariograms for 27 data sets, i.e. three different soil properties, each of them sampled in three treatments and during three dates. Soil extractable and Fe, Mn and Zn exhibited a rather strong spatial dependence, as nugget variance was either null or a small proportion of the total variance, and this all over the three different study periods and for the three lime treatments. Geostatistical analysis provided insight into possible processes responsible of the observed spatial variability patterns within the rice soil. Kriging was useful in mapping soil micronutrient variability allowing identifying microrregions with high or low Fe, Mn and Zn concentrations, which showed the presence of small scale variability. These findings indicate the potential for applying the principles of precision agriculture to control spatiotemporal variability in rice fields.

Spatial Distribution and Temporal Variability of Ammonium-Nitrogen, Phosphorus, and Potassium in a Rice Field in Corrientes, Argentina

“…Three successive sampling campaigns were carried out to assess the stability of the spatial distribution along the growing season of the studied soil properties. Results reported on previous work for pH and Eh [ 17 ] and for extractable Fe, Mn, and Zn [ 12 ] showed a rather strong seasonality in the spatial distribution of these variables with changing patterns between sampling dates. Seasonal stability of nutrient maps has been considered as a prerequisite for efficient precision agriculture management [ 20 ].…”

“…However, more recently it has also been shown that factors such as small differences in elevation after land-levelling [ 18 ] and redistribution of soil components and/or nutrients by lateral water movement across neighbouring small fields surrounded by ridges [ 19 , 20 ] may drive heterogeneity of crop yield and soil properties at different scales. Temporal oscillations in the spatial patterns of variability of soil properties or soil nutrients in rice fields have been also previously reported [ 12 , 13 , 16 , 20 ], even if this issue has been less frequently addressed.…”

“…More recently, the value of spatial measurements of soil properties coupled with geostatistical techniques to develop site specific management practices also has been widely acknowledged [ 2 , 9 , 10 ]. Indeed, geostatistical analysis has been carried out to assess heterogeneity in paddy soils, focussing either on soil properties and/or crop yield [ 5 , 11 ] or on soil properties and/or nutrients [ 12 – 17 ].…”

“…Because these soils are characterized by a relatively flat topography and seasonal flooding, in the past they have been thought to be apparently homogeneous. However, large spatial variability in soil properties has been reported for paddy fields of different countries [ 5 , 11 , 12 , 14 , 16 ], even if at a first sight this might be considered as a quite unexpected result. However, more recently it has also been shown that factors such as small differences in elevation after land-levelling [ 18 ] and redistribution of soil components and/or nutrients by lateral water movement across neighbouring small fields surrounded by ridges [ 19 , 20 ] may drive heterogeneity of crop yield and soil properties at different scales.…”

Low water input confers sustainable rice production without affecting soil, plant physiological and yields parameters

“…The redox potential (Eh) of flooded rice soil is low and NO , and S 2− (Fan et al, 2008). The flooding condition increases the availability of phosphorus (Gupta et al, 2007, Jahan, 2016 and controls soil pH, chemical equilibrium and induce the phytoavailability of plant nutrients (Morales et al, 2011;Jahan, 2016). The influences of flooding on physical, chemical and electrochemical properties of the soil were comprehensively documented and reviewed (Narteh and Sahrawat, 1999;De Datta, 1981).…”