Nitrogen fertilizer (15N) leaching in a central pivot fertigated coffee crop

Nitrogen has a complex dynamics in the soil-plant-atmosphere system. N fertilizers are subject to chemical and microbial transformations in soils that can result in significant losses. Considering the cost of fertilizers, the adoption of good management practices like fertigation could improve the N use efficiency by crops. Water balances (WB) were applied to evaluate fertilizer N leaching using 15N labeled urea in west Bahia, Brazil. Three scenarios (2008/2009) were established: i) rainfall + irrigation the full year, ii) rainfall only; and iii) rainfall + irrigation only in the dry season. The water excess was considered equal to the deep drainage for the very flat area (runoff = 0) with a water table located several meters below soil surface (capillary rise = 0). The control volume for water balance calculations was the 0 - 1 m soil layer, considering that it involves the active root system. The water drained below 1 m was used to estimate fertilizer N leaching losses. WB calculations used the mathematic model of Penman-Monteith for evapotranspiration, considering the crop coefficient equal to unity. The high N application rate associated to the high rainfall plus irrigation was found to be the main cause for leaching, which values were 14.7 and 104.5 kg ha-1 for the rates 400 and 800 kg ha-1 of N, corresponding to 3.7 and 13.1 % of the applied fertilizer, respectively.

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Minimizing Soil Nitrogen Leaching by Changing Furrow Irrigation into Sprinkler Fertigation in Potato Fields in the Northwestern China Plain

Water ◽

10.3390/w12082229 ◽

2020 ◽

Vol 12 (8) ◽

pp. 2229

Author(s):

Wenzhu Yang ◽

Yan Jiao ◽

Mingde Yang ◽

Huiyang Wen ◽

Peng Gu ◽

...

Keyword(s):

Soil Profile ◽

Management Practices ◽

Root Zone ◽

Soil Depth ◽

Irrigation System ◽

Nitrogen Loss ◽

Soil Layer ◽

Furrow Irrigation ◽

N Leaching ◽

N Accumulation

Irrigation water is limiting for crop production in arid areas and application rates of fertilizers often exceed crop requirements, resulting in high accumulation of nitrate nitrogen (NO3−-N) in the soil. Management practices play a significant role in the leaching of NO3−-N. This experiment compares the effects of traditional furrow irrigation and sprinkler fertigation on the soil NO3−-N concentration trend throughout the cropping season in potato fields in China. Two irrigation systems that were fertilized, namely by furrow (NF-FI) and sprinkler fertigation (NF-SI), and two controlling without any fertilizer (C-FI and C-SI) were tested in the same experimental site for three consecutive years. Both the NF-FI soils and NF-SI soils with three replications and fertilizer applications of 273 kg N ha−1 exhibited a different trend of NO3−-N accumulation at different depths of soil profile. However, the magnitude of NO3−-N accumulation was low in the NF-SI soil profile. In NF-SI treatments, higher NO3−-N was observed at 20–40 cm soil layer. In the NF-FI, the concentration of the highest nitrate was observed at the 40–120 cm soil layer. The concentrations of NO3−-N in the fertilized soil were higher than those of the control soil for each irrigation system. Residual levels of NO3−-N in the soil depth of 40–120 cm from NF-FI were 1.54, 3.45 and 5.28 times higher than NF-SI after harvesting potatoes from 2015 to 2017. In NF-FI treatments, apparent nitrogen loss was 234.7, 237.5 and 276.7 kg ha−1 after harvesting potatoes in 2015, 2016 and 2017. Meanwhile, apparent nitrogen loss from NF-SI treatments was only 161.9, 132.1 and 148.9 kg ha−1, which was 31.0%, 44.4% and 46.2% lower than that of NF-FI in 2015, 2016 and 2017, respectively. The risk of NO3−-N leaching below the root zone from NF-FI was higher than that from NF-SI. It has been demonstrated that sprinkler fertigation can also be used as a tool for mitigating NO3−-N accumulation and apparent nitrogen loss.

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Nitrogen doses and water balance components at phenological stages of corn

Scientia Agricola ◽

10.1590/s0103-90162009000400013 ◽

2009 ◽

Vol 66 (4) ◽

pp. 515-521 ◽

Cited By ~ 7

Author(s):

Monica Martins da Silva ◽

Paulo Leonel Libardi ◽

Flávia Carvalho Silva Fernandes

Keyword(s):

Water Balance ◽

Soil Water ◽

Control Volume ◽

Capillary Rise ◽

Soil Layer ◽

Soil Water Balance ◽

Water Balance Components ◽

Phenological Stages ◽

Unknown Quantity ◽

D Values

Determining the intensity of the water balance components in the control volume of a soil, and consequently defining the most likely periods of occurrence of a water deficit in a crop, is an exercise that requires knowledge about soil, climate and plant factors. This research aimed to evaluate soil water balance components at phenological stages of corn (Zea mays L.) under no-till system, when fertilized with 60, 120, and 180 kg ha-1 of nitrogen. The field experiment was carried out in Piracicaba, State of São Paulo, Brazil, on a Typic Hapludox. Evaluations were made in the 2004/2005 and 2005/2006 corn cropping seasons, divided over three stages according to the plant's phenology. Runoff was not taken into account. Measurements were made for precipitation (P), internal drainage (D) (or capillary rise) at a 0.8 m depth, and water storage variation (Δh) in the soil layer from 0.0-0.80 m; actual evapotranspiration (ET) was considered the unknown quantity of the equation. Corn grain yield was evaluated as well. In general, the soil water balance components were modified by N doses, because the soil had been relatively smaller Δh in treatments involving N application than in the treatment without N, resulting in smaller D values in those treatments, which resulted in greater absorption by the plants and greater ET. As expected, the plant developmental stage II had a higher ET value.

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Coastal saline Soils of India: A review

Agricultural Reviews ◽

10.18805/ag.r-1768 ◽

2018 ◽

Vol 38 (01) ◽

Author(s):

V. Sabareshwari ◽

A. Ramya

Keyword(s):

Tamil Nadu ◽

Management Practices ◽

Sea Water ◽

Capillary Rise ◽

Coastal Region ◽

Soil Surface ◽

Anthropogenic Contamination ◽

Rock Interaction ◽

Coastal Soils

Coastal region covers a long strip along the east coast (West Bengal, Orissa, Andhra Pradesh, Pondicherry and Tamil Nadu) and west coast (Gujarat, Maharashtra, Karnataka and Kerala). Salinity is mainly due to the presence of saline ground water at shallow depth and frequent sea water inundation in the low lying areas. Sea water intrusion into the aquifers may be direct, but also range of complex geochemical processes like, inter-aquifer mixing, mobilization of brines, water-rock interaction and anthropogenic contamination. NaCl and Na2SO4 are the dominant salts, with abundance of soluble cations in the order of Na>Mg>Ca>K. The salt reaches the soil surface through capillary rise during dry season and makes the soil saline and unproductive for agriculture. Salinity ranges 0.5 dSm-1 in monsoon and 50 dSm-1 in summer. Proper understanding about the nature, properties and prevailing constraints related to diverse group of coastal soils is necessary to undertake better management practices to improve the productivity and quality of such low productive salty soils.

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Fertilizer 15N balance in a coffee cropping system: a case study in Brazil

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832008000400010 ◽

2008 ◽

Vol 32 (4) ◽

pp. 1459-1469 ◽

Cited By ~ 10

Author(s):

Tatiele Anete Bergamo Fenilli ◽

Klaus Reichardt ◽

José Laércio Favarin ◽

Osny Oliveira Santos Bacchi ◽

Adriana Lúcia Silva ◽

...

Keyword(s):

Ammonium Sulfate ◽

Management Practices ◽

Soil Depth ◽

N Recovery ◽

15N Balance ◽

Fertilizer N ◽

Perennial Crop ◽

Deep Drainage ◽

N Losses ◽

Total N

Knowledge about the fate of fertilizer nitrogen in agricultural systems is essential for the improvement of management practices in order to maximize nitrogen (N) recovery by the crop and reduce N losses from the system to a minimum. This study involves fertilizer management practices using the 15N isotope label applied in a single rate to determine the fertilizer-N balance in a particular soil-coffee-atmosphere system and to deepen the understanding of N plant dynamics. Five replicates consisting of plots of about 120 plants each were randomly defined within a 0.2 ha coffee plantation planted in 2001, in Piracicaba, SP, Brazil. Nine plants of each plot were separated in sub-plots for the 15N balance studies and treated with N rates of 280 and 350 kg ha-1 during 2003/2004 and 2004/2005, respectively, both of them as ammonium sulfate enriched to a 15N abundance of 2.072 atom %. Plant shoots were considered as separate parts: the orthotropic central branch, productive branches, leaves of productive branches, vegetative branches, leaves of vegetative branches and fruit. Litter, consisting of dead leaves accumulated below the plant canopy, was measured by the difference between leaves at harvest and at the beginning of the following flowering. Roots and soil were sampled down to a depth of 1.0 at intervals of 0.2 m. Samples from the isotopic sub-plots were used to evaluate total N and 15N, and plants outside sub-plots were used to evaluate dry matter. Volatilization losses of NH3 were estimated using special collectors. Leaching of fertilizer-N was estimated from deep drainage water fluxes and 15N concentrations of the soil solution at 1 m soil depth. At the end of the 2-year evaluation, the recovery of 15N applied as ammonium sulfate was 19.1 % in aerial plant parts, 9.4 % in the roots, 23.8 % in the litter, 26.3 % in the fruit and 12.6 % remaining in the 0_1.0 m soil profile. Annual leaching and volatilization losses were very small (2.0 % and 0.9 %, respectively). After two years, only 6.2 % N were missing in the balance (100 %) which can be attributed to other non-estimated compartments and experimental errors. Results show that an enrichment of only 2 % atom 15N allows the study of the partition of fertilizer-N in a perennial crop such as coffee during a period of two years.

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Field Measurements and Simulation of Nitrogen Fate under Citrus Production

HortScience ◽

10.21273/hortsci.33.3.498c ◽

1998 ◽

Vol 33 (3) ◽

pp. 498c-498

Author(s):

A. Fares ◽

A.K. Alva ◽

S. Paramasivam

Keyword(s):

Mass Balance ◽

Best Management Practices ◽

Rainy Season ◽

Crop Production ◽

Management Practices ◽

Root Zone ◽

Field Measurements ◽

Irrigation Scheduling ◽

N Leaching ◽

Citrus Production

Water and nitrogen (N) are important inputs for most crop production. The main objectives of nitrogen best management practices (NBMP) are to improve N and water management to maximize the uptake efficiency and minimize the leaching losses. This require a complete understanding of fate of N and water mass balance within and below the root zone of the crop in question. The fate of nitrogen applied for citrus production in sandy soils (>95% sand) was simulated using a mathematical model LEACHM (Leaching Estimation And Chemistry Model). Nitrogen removal in harvested fruits and storage in the tree accounted the major portion of the applied N. Nitrogen volatilization mainly as ammonia and N leaching below the root zone were the next two major components of the N mass balance. A proper irrigation scheduling based on continuous monitoring of the soil water content in the rooting was used as a part of the NBMP. More than 50% of the total annual leached water below the root zone was predicted to occur in the the rainy season. Since this would contribute to nitrate leaching, it is recomended to avoid N application during the rainy season.

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Corrigendum to: Conservation agriculture effects on soil properties and crop productivity in a semiarid region of India

Soil Research ◽

10.1071/sr18145_co ◽

2019 ◽

Vol 57 (2) ◽

pp. 200 ◽

Cited By ~ 1

Author(s):

J. Somasundaram ◽

M. Salikram ◽

N. K. Sinha ◽

M. Mohanty ◽

R. S. Chaudhary ◽

...

Keyword(s):

Soil Properties ◽

Management Practices ◽

Crop Yields ◽

Cropping Systems ◽

Soil Layer ◽

Conservation Agriculture ◽

Semiarid Region ◽

Reduced Tillage ◽

Organic C ◽

Residue Retention

Conservation agriculture (CA) including reduced or no-tillage and crop residue retention, is known to be a self–sustainable system as well as an alternative to residue burning. The present study evaluated the effect of reduced tillage coupled with residue retention under different cropping systems on soil properties and crop yields in a Vertisol of a semiarid region of central India. Two tillage systems – conventional tillage (CT) with residue removed, and reduced tillage (RT) with residue retained – and six major cropping systems of this region were examined after 3 years of experimentation. Results demonstrated that soil moisture content, mean weight diameter, percent water stable aggregates (>0.25mm) for the 0–15cm soil layer were significantly (Pmoderately labile>less labile. At the 0–15cm depth, the contributions of moderately labile, less labile and non-labile C fractions to total organic C were 39.3%, 10.3% and 50.4% respectively in RT and corresponding values for CT were 38.9%, 11.7% and 49.4%. Significant differences in different C fractions were observed between RT and CT. Soil microbial biomass C concentration was significantly higher in RT than CT at 0–15cm depth. The maize–chickpea cropping system had significantly (P–1 followed by soybean+pigeon pea (2:1) intercropping (3.50 t ha–1) and soybean–wheat cropping systems (2.97 t ha–1). Thus, CA practices could be sustainable management practices for improving soil health and crop yields of rainfed Vertisols in these semiarid regions.

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Coal Fly Ash and Polyacrylamide Influence Transport and Redistribution of Soil Nitrogen in a Sandy Sloping Land

Agriculture ◽

10.3390/agriculture11010047 ◽

2021 ◽

Vol 11 (1) ◽

pp. 47

Author(s):

Kai Yang ◽

Zejun Tang ◽

Jianzhang Feng

Keyword(s):

Fly Ash ◽

Sandy Soil ◽

Coal Fly Ash ◽

Soil Layer ◽

Nutrient Retention ◽

Soil Surface ◽

Rainfall Event ◽

N Losses ◽

N Concentration ◽

Application Rates

Sandy soils are prone to nutrient losses, and consequently do not have as much as agricultural productivity as other soils. In this study, coal fly ash (CFA) and anionic polyacrylamide (PAM) granules were used as a sandy soil amendment. The two additives were incorporated to the sandy soil layer (depth of 0.2 m, slope gradient of 10°) at three CFA dosages and two PAM dosages. Urea was applied uniformly onto the low-nitrogen (N) soil surface prior to the simulated rainfall experiment (rainfall intensity of 1.5 mm/min). The results showed that compared with no addition of CFA and PAM, the addition of CFA and/or PAM caused some increases in the cumulative NO3−-N and NH4+-N losses with surface runoff; when the rainfall event ended, 15% CFA alone treatment and 0.01–0.02% PAM alone treatment resulted in small but significant increases in the cumulative runoff-associated NO3−-N concentration (p < 0.05), meanwhile 10% CFA + 0.01% PAM treatment and 15% CFA alone treatment resulted in nonsignificant small increases in the cumulative runoff-associated NH4+-N concentration (p > 0.05). After the rainfall event, both CFA and PAM alone treatments increased the concentrations of NO3−-N and NH4+-N retained in the sandy soil layer compared with the unamended soil. As the CFA and PAM co-application rates increased, the additive effect of CFA and PAM on improving the nutrient retention of sandy soil increased.

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Earthworm Abundance Changes Depending on Soil Management Practices in Slovenian Vineyards

Agronomy ◽

10.3390/agronomy11061241 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1241

Author(s):

Stanko Vršič ◽

Marko Breznik ◽

Borut Pulko ◽

Jesús Rodrigo-Comino

Keyword(s):

Management Practices ◽

Human Impacts ◽

Soil Layer ◽

Soil Management ◽

Weather Conditions ◽

Soil Tillage ◽

Soil Biodiversity ◽

Straw Mulch ◽

Green Cover ◽

The Impact

Earthworms are key indicators of soil quality and health in vineyards, but research that considers different soil management systems, especially in Slovenian viticultural areas is scarce. In this investigation, the impact of different soil management practices such as permanent green cover, the use of herbicides in row and inter-row areas, use of straw mulch, and shallow soil tillage compared to meadow control for earthworm abundance, were assessed. The biomass and abundance of earthworms (m2) and distribution in various soil layers were quantified for three years. Monitoring and a survey covering 22 May 2014 to 5 October 2016 in seven different sampling dates, along with a soil profile at the depth from 0 to 60 cm, were carried out. Our results showed that the lowest mean abundance and biomass of earthworms in all sampling periods were registered along the herbicide strip (within the rows). The highest abundance was found in the straw mulch and permanent green cover treatments (higher than in the control). On the plots where the herbicide was applied to the complete inter-row area, the abundance of the earthworm community decreased from the beginning to the end of the monitoring period. In contrast, shallow tillage showed a similar trend of declining earthworm abundance, which could indicate a deterioration of soil biodiversity conditions. We concluded that different soil management practices greatly affect the soil’s environmental conditions (temperature and humidity), especially in the upper soil layer (up to 15 cm deep), which affects the abundance of the earthworm community. Our results demonstrated that these practices need to be adapted to the climate and weather conditions, and also to human impacts.

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Evaluation of Image-Based Phenotyping Methods for Measuring Water Yam (Dioscorea alata L.) Growth and Nitrogen Nutritional Status under Greenhouse and Field Conditions

Agronomy ◽

10.3390/agronomy11020249 ◽

2021 ◽

Vol 11 (2) ◽

pp. 249

Author(s):

Emmanuel Frossard ◽

Frank Liebisch ◽

Valérie Kouamé Hgaza ◽

Delwendé Innocent Kiba ◽

Norbert Kirchgessner ◽

...

Keyword(s):

Management Practices ◽

Leaf Surface ◽

Plant Traits ◽

Soil Surface ◽

Shoot Biomass ◽

N Content ◽

Total Leaf ◽

Image Pixels ◽

Leaf N Content ◽

Yield Formation

New management practices must be developed to improve yam productivity. By allowing non-destructive analyses of important plant traits, image-based phenotyping techniques could help developing such practices. Our objective was to determine the potential of image-based phenotyping methods to assess traits relevant for tuber yield formation in yam grown in the glasshouse and in the field. We took plant and leaf pictures with consumer cameras. We used the numbers of image pixels to derive the shoot biomass and the total leaf surface and calculated the ‘triangular greenness index’ (TGI) which is an indicator of the leaf chlorophyll content. Under glasshouse conditions, the number of pixels obtained from nadir view (view from the top) was positively correlated to shoot biomass, and total leaf surface, while the TGI was negatively correlated to the SPAD values and nitrogen (N) content of diagnostic leaves. Pictures taken from nadir view in the field showed an increase in soil surface cover and a decrease in TGI with time. TGI was negatively correlated to SPAD values measured on diagnostic leaves but was not correlated to leaf N content. In conclusion, these phenotyping techniques deliver relevant results but need to be further developed and validated for application in yam.

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Application of the vertical model of the seasonally thawed layer for the Tulik Lake area (Alaska)

Вычислительные технологии ◽

10.25743/ict.2021.26.4.002 ◽

2021 ◽

pp. 4-15

Author(s):

Виктор Михайлович Белолипецкий ◽

Светлана Николаевна Генова

Keyword(s):

Air Temperature ◽

Stefan Problem ◽

Soil Layer ◽

Vertical Direction ◽

Soil Surface ◽

Dirichlet Condition ◽

Transfer Model ◽

Problem Solution ◽

Computational Domain ◽

Lake Area

Практический интерес в районах вечной мерзлоты представляет глубина сезонного оттаивания. Построена одномерная (в вертикальном направлении) упрощенная полуэмпирическая модель динамики вечной мерзлоты в “приближении медленных движений границ фазового перехода”, основанная на задаче Стефана и эмпирических соотношениях. Калибровочные параметры модели выбираются для исследуемого района с использованием натурных измерений глубины оттаивания и температуры воздуха. Проверка работоспособности численной модели проведена для района оз. Тулик (Аляска). Получено согласие рассчитанных значений глубины талого слоя и температуры поверхности почвы с результатами измерений Due to the change in global air temperature, the assessment of permafrost reactions to climate change is of interest. As the climate warms, both the thickness of the thawed soil layer and the period for existence of the talik are increased. The present paper proposes a small-size numerical model of vertical temperature distributions in the thawed and frozen layers when a frozen layer on the soil surface is absent. In the vertical direction, thawed and frozen soils are separated. The theoretical description of the temperature field in soils when they freeze or melt is carried out using the solution of the Stefan problem. The mathematical model is based on thermal conductivity equations for the frozen and melted zones. At the interfacial boundary, the Dirichlet condition for temperature and the Stefan condition are set. The numerical methods for solving of Stefan problems are divided into two classes, namely, methods with explicit division of fronts and methods of end-to-end counting. In the present work, the method with the selection of fronts is implemented. In the one-dimensional Stefan problem, when transformed to new variables, the computational domain in the spatial variable is mapped onto the interval [0 , 1]. In the presented equations, the convective terms characterize the rate of temperature transfer (model 1). A simplified version of the Stefan problem solution is considered without taking into account this rate (“approximation of slow movements of the boundaries of the phase transition”, model 2). The model is tuned to a specific object of research. Model parameter values can vary significantly in different geographic regions. This paper simulates the dynamics of permafrost in the area of Lake Tulik (Alaska) in summer. Test calculations based on the proposed simplified model show its adequacy and consistency with field measurements. The developed model can be used for qualitative studies of the long-term dynamics of permafrost using data of the air temperature, relative air humidity and precipitation

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