Citrus Residue Enhances the Effectiveness of Beef Cattle Manure Improving the Phosphorus Availability in Acidic Andisol

ABSTRACT

Phosphorus availability and acid pH are major limiting factors for grass and crop production in the Andisols of Southern Chile. Sustainable management requires both the efficient use of fertilizers and the recycling of agricultural waste. The aim of this study was to investigate the effect of citrus waste, alone or in combination with beef cattle manure (CM), on phosphorus availability. Controlled laboratory incubations were carried out for up to six weeks. Lemon (L) and mandarin (M) fruit wastes were added to an Andisol, amended or not with dried CM. Fruit parts (Peel, Juice or whole fruit), and for whole fruit the size of the fruit pieces added to soil, were compared. Water-extractable (WE) P, phosphatase activity (P-ase), and pH were monitored. In general, the size and distribution of the citrus fruit wastes gave similar trends in WE-P, P-ase, and pH. Lemon induced larger effects on WE-P and pH than did mandarin. CM caused sustained soil alkalization, increased soil WE-P and P-ase. Citrus addition produced a short-lived acidification followed by net alkalization and immediate increases in WE-P and P-ase. The combined amendment with citrus wastes enhanced the positive effect of CM on soil WE-P and alkalization, with only a small effect on P-ase. These findings indicate that citrus wastes would intensify the beneficial effects of CM amendment on soil P availability and additionally the liming effect on acid soils.

KEYWORDS:

• Organic residues
• cost effective soil amendment
• liming effect
• sustainable agriculture
• water-extractable phosphorus
• phosphatase activity

Acknowledgments

We would like to thank the Scientific and Technological Bioresource Nucleus (BIOREN-UFRO) and Soil and Plant Laboratory of Universidad de La Frontera for providing access to specialized equipment.

Disclosure statement

All authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Author contributions

The work presented here was carried out in collaboration between all authors. CP and MLM defined the research theme. CP performed all the experiments under the supervision of SS and MLM. CP, SS, MR, AV and MLM wrote the manuscript. All authors have contributed to, seen and approved the manuscript.

Additional information

Funding

This work was supported by the FONDECYT 1181050.