Phosphate fertilization strategies for soybean production after conversion of a degraded pastureland to a no-till cropping system
Introduction
In Brazil, low yield pasturelands cover approximately 200 million hectares (Mha), and about 20% of these areas are degraded (Barretto et al., 2013, Dias-Filho, 2014). Increased yields in these areas, without associated environmental risks, are possible if good management practices are applied, especially with regard to soil fertility (Bruun et al., 2015, Cerdà et al., 2009). Conservative agriculture practices that avoid improper management are essential to the establishment of agricultural crops on previously degraded soils, which is particularly important because these soils are highly vulnerable to erosion (Cerdà, 2000, Trabaquini et al., 2015). The no-till system is a recommended conservation system for annual crops in Brazil, and it is currently used in just over 32 Mha (Derpsch et al., 2010). The establishment of no-till cropping systems is beneficial to improve yield and to cultivate annual crops in previously degraded pasturelands. However, several limitations need to be addressed, especially those associated with soil fertility.
The low availability of phosphorus (P) in the soil is a concern in degraded pastureland restoration. This plant nutrient is likely to be in short supply and, therefore, techniques that recycle P and minimize its loss should be developed (Lal, 2001). The consumption of fertilizers including P has recently increased, especially in tropical regions (Cordell and White, 2011, Rodrigues et al., 2016), due to high P fixation in highly weathered soils (which require high P concentrations) and to increased P demand resulting from the inclusion of new croplands (typically degraded areas) that require high P addition (Rodrigues et al., 2016, Santos et al., 2008, Tiecher et al., 2015). The efficiency of P use is associated with the ability of a cultivated crop to acquire this nutrient. Some studies in Brazil showed the remarkable importance of soil organic P in the enhancement of P-use efficiency (Carvalho et al., 2014, Rosolem and Calonego, 2013, Tiecher et al., 2012).
The cultivation of cover crops during the winter is a common practice in Southern Brazil, and this practice can help ensure high levels of organic P. In highly weathered soils, P fixation is a concern. To increase P availability in these soils, it is important to ensure proper P sources and application times (Novais and Smyth, 1999). Plants with enhanced capacity to absorb P from the soil can help recycle P, especially if they are cultivated as cover crops. Black oat (Avena strigosa Schreb.) is a cover crop with this capacity (Dalla Costa and Lovato, 2004), as well as other cover crops cultivated in tropical regions (Almeida and Rosolem, 2016, Merlin et al., 2013, Teles et al., 2017). Increased P recycling results in a reduced time of mineral P exposure to soil particles, and this might help minimize P fixation. However, several uncertainties remain about the feasibility of applying P-fertilizers to cover crops and these uncertainties must be addressed to boost P recycling and to potentially provide P to the grain crops cultivated after cover crops.
The success of P management also depends on the P source. Several studies have demonstrated the feasibility of less soluble P sources (Chien et al., 2009, Galvani et al., 2008, Olibone and Rosolem, 2010, Prochnow et al., 2006). When using P sources with higher solubility (e.g., superphosphates), it is necessary to ensure P supply during times of higher P uptake (Raij, 2011). However, if part of the P supply is not properly used by the crop, the risk of loss increases. In this sense, less soluble P sources might be an interesting alternative, particularly when applied in advance and in narrow rows to simulate total incorporation into the soil. On the other hand, P sources with high water-soluble P contents can provide enough P for cover crop development, thus increasing soil protection and P recycling.
Improvements in soil-P status during the conversion from degraded pasturelands to no-till cropping systems are highly important. However, there are concerns about better strategies that improve soil-P efficiently without using high P inputs. In highly weathered soils, it is essential to ensure good soil cover for the establishment of a no-till system. In this regard, phosphate fertilization on the cover crop is promising, since it improves both P recycling and crop development. Moreover, the application of P to the winter crop row instead of the soybean row results in advantages regarding the rapidity of soybean sowing operations, which could help avoid late sowing and the subsequent crop yield restrictions (Pavinato and Ceretta, 2004), and improves horizontal P distribution. Therefore, this study aimed to evaluate the effects of P fertilization strategies, using a 4-year black oat-soybean succession, by varying P sources and P application times to ensure improved no-till establishments in a previously degraded pastureland.
Section snippets
Field and soil characterization and agricultural management
The experiment was performed in Ponta Grossa, PR, Brazil (25°10′S; 50°05′W) on an Oxisol (sandy loam, kaolinitic, and thermic Typic Hapludox). According to the Köppen-Geiger System (Peel et al., 2007), the climate at the site is categorized as a Cfb type (mesothermal, humid, and subtropical) with mild summers and frequent frosts during the winter. The average altitude is 970 m, and average maximum and minimum temperatures are 22 and 13 °C, respectively; annual rainfall is approximately 1550 mm.
Results
Table 2 presents the results of the soil samplings performed after the soybean harvest in 2013. Therefore, sampling was conducted after the cultivation of four black oat-soybean cycles and a total application of 176 kg ha− 1 P. Soil-P values at all studied depths were significantly influenced by the interaction effects of P-fertilizer sources and application times (Table 2). Overall, soil-P values were highest in the treatments in which P was applied to the soybean furrow at all evaluated soil
Soil-P status changes
The use of all P sources resulted in improved soil P contents (Table 2). Despite the differences observed between sources at studied depths, the mean values at the 0–0.20 m layer at different application times were similar after P fertilization: 14.2 mg dm− 3 with RPR, 11.6 mg dm− 3 with TP, and 14.0 mg dm− 3 with TSP (Table 2). Overall, the highest P-soil levels were observed after the application of TSP and RPR sources. The TSP source presented greater solubility in water than the other sources, so
Conclusions
The soil P status of a degraded pastureland improved by no-till establishment and P fertilization in crop furrows, indicating the usefulness of this practice for soil fertility restoration. The interpretation of soil-P levels in the production system should account for the effects of management practices such as P recycling by cover crops, banded P application, soil sampling methods, and P-fertilizer sources.
Phosphate fertilizer application at the sowing of cover crop (black oat) in degraded
Acknowledgments
We are grateful to CAPES for providing the second author with a scholarship and the company Fertisystem for providing the precision-fertilizer-dosing system.
Funding
This work was supported by CNPq [grant numbers 480447/2008-0 and 304208/2010-8] for research funding and the scholarship for corresponding author.
References (71)
Aggregate stability against water forces under different climates on agriculture land and scrubland in southern Bolivia
Soil Tillage Res.
(2000)- et al.
Soil erosion and agriculture
Soil Tillage Res.
(2009) - et al.
Recent developments of fertilizer production and use to improve nutrient efficiency and minimize environmental impacts
Adv. Agron.
(2009) - et al.
Recognizing the role of soil organic phosphorus in soil fertility and water quality
Resour. Conserv. Recycl.
(2015) - et al.
Adsorption and desorption of phosphorus in subtropical soils as affected by management system and mineralogy
Soil Tillage Res.
(2016) - et al.
Liming in the conversion from degraded pastureland to a no-till cropping system in southern Brazil
Soil Tillage Res.
(2016) - et al.
Sense and nonsense in conservation agriculture: principles, pragmatism and productivity in Australian mixed farming systems
Agric. Ecosyst. Environ.
(2014) - et al.
Phosphorus fractions in Brazilian Cerrado soils as affected by tillage
Soil Tillage Res.
(2009) - et al.
Legacy phosphorus and no-tillage agriculture in tropical Oxisols of the Brazilian savanna
Sci. Total Environ.
(2016) - et al.
Phosphorus and potassium budget in the soil – plant system in crop rotations under no-till
Soil Tillage Res.
(2013)
Soil phosphorus dynamics during 17 years of continuous cultivation: a method to estimate long-term P availability
Geoderma
Ruzigrass grown in rotation with soybean increases soil labile phosphorus
Agron. J.
Potential of carbon accumulation in no-till soils with intensive use and cover crops in southern Brazil
J. Environ. Qual.
Agricultural intensification in Brazil and its effects on land-use patterns: an analysis of the 1975–2006 period
Glob. Chang. Biol.
Soil phosphate chemistry and the P-sparing effect of previous phosphate applications
Plant Soil
Soybean sowing date: the vegetative, reproductive, and agronomic impacts
Crop Sci.
Nutrient uptake, partitioning, and remobilization in modern soybean varieties
Agron. J.
Principles of Soil Conservation and Management
Phosphorus sorption by sandy soils from Western Australia: effect of previously sorbed P on P buffer capacity and single-point P sorption indices
Aust. J. Soil Res.
Nutrientes minerais na biomassa da parte aérea em culturas de cobertura de solo
Pesqui. Agropecu. Bras.
Organic carbon dynamics in different soil types after conversion of forest to agriculture
Land Degrad. Dev.
Performance of maize landrace under no-till as affected by the organic and mineral fertilizers
Braz. Arch. Biol. Technol.
Phosphorus and potassium balance in a corn-soybean rotation under no-till and chiseling
Nutr. Cycl. Agroecosyst.
Forms of phosphorus in an Oxisol under different soil tillage systems and cover plants
Rev. Bras. Ciênc. Solo
Agronomic use of phosphate rock for direct application
Better Crop.
Peak phosphorus: clarifying the key issues of a vigorous debate about long-term phosphorus security
Sustainability
Phosphorus in soil and soybean growth as affected by phosphate fertilization and cover crop residues
Pesq. Agrop. Brasileira
Taxas de decomposição e de liberação de macronutrientes da palhada de aveia preta em plantio direto
Bragantia
Fosfatases na dinâmica do fósforo do solo sob culturas de cobertura com espécies micorrízicas e não micorrízicas
Pesq. Agrop. Brasileira
Current status of adoption of no-till farming in the world and some of its main benefits
Int. J. Agric. Biol. Eng.
Diagnóstico das Pastagens no Brasil
Manual de métodos de análise de solos
Stage of development descriptions for soybeans, Glycine max (L.) Merrill
Crop Sci.
Sisvar: a computer statistical analysis system
Cienc. Agrotecnol.
Agronomy of Oats
Cited by (14)
Spatial distribution of soil phosphorus fractions in a clayey Oxisol submitted to long-term phosphate fertilization strategies
2022, GeodermaCitation Excerpt :Phosphate sources of medium solubility can be considered as slow-release P fertilizers. Applications of reactive phosphate rock (RPR) to low STP areas are often initially less effective than that of an equivalent total P dose of a water soluble phosphate source (Caires et al., 2017; Nunes et al., 2020). However, in the long-term the residual effect of RPR P inputs to soils is more pronounced than when a soluble source is used (Oliveira et al., 2019).
Phosphorus speciation by P-XANES in an Oxisol under long-term no-till cultivation
2020, GeodermaCitation Excerpt :As a result, the efficiency of P fertilization in these areas is generally low (Bayuelo-Jiménezet al., 2020; Pradhan et al., 2020). Many attempts to increase P use efficiency (PUE) in tropical soils have been made including the use of P-rich animal wastes as P sources (Abdala et al., 2012; Boitt et al., 2018), application of organo-mineral P fertilizers (Corrêa et al., 2018; Borges et al., 2019), improved P fertilizer placement (Vandamme et al., 2018; Williams et al., 2018), induced P solubilization by root and microbial processes (Richardson et al., 2011), and by adopting soil cultivation practices that could lower P retention in soils, such as no-tillage (NT) system (Abdala et al., 2015a; Caires et al., 2017; Tiecher et al., 2017). Among the strategies to increase P availability to plants, the adoption of NT is the most practical one for farmers.
Recovery of light rare earth elements by leaching and extraction from phosphate mining waste (Fluorapatite and Carbonate-Fluorapatite)
2020, Journal of African Earth SciencesCitation Excerpt :Algeria produces more than 2 million tons of phosphates per year, thanks to the Kef Es Sennoun deposit, a complex of Djebel-onk located at 600 km southeast of Algiers (Bezzi et al., 2012) (Fig. 1). Phosphates are crucial in life, besides the economic benefits, they have various applications in agriculture, where they are used for the fertilization and enrichment of soils (Caires et al., 2017). A deposit of Kef Es Sennoun is dedicated only to the exploitation of phosphates, ensured by the Somiphos Society.
National-scale evaluation of phosphorus emissions and the related water-quality risk hotspots accompanied by increased agricultural production
2018, Agriculture, Ecosystems and EnvironmentCitation Excerpt :Previous studies have reported that the majority of agricultural P emissions are driven by storm events and delivered via overland flow as non-point source (NPS) pollution (Chen et al., 2017, 2014). To date, the recognition of the impacts of agricultural fertilizer application on aquatic systems has driven observational networks at plot and catchment scales, as well as the funding of models and remote sensing to expand studies to regional, national, and even global scales (Caires et al., 2017; Ju et al., 2009). However, considerable uncertainty remains in our knowledge of the sources, magnitude, and spatial-temporal changes of agriculture non-point-source phosphorus (NPS-P) emissions, especially for large-scale regions (Chen et al., 2016).
The management of phosphate fertilization affects soil phosphorus and yield of autumn/winter crops
2023, Acta Scientiarum - AgronomyChallenges for sustainable production in sandy soils: A review
2023, Environment, Development and Sustainability