Long-Term Effects of Animal Manures on Nutrient Recovery and Soil Quality in Acid Typic Hapludalf under No-Till Conditions

Abstract

No-till farming and manure application are means of storing carbon in soil and increasing soil quality. However, the organic fertilization of no-till soils may sustain subtropical agroecosystems for only a limited period until the soil quality declines. The C, N, P, and other nutrient cycles are perturbed due to the nutrient imbalance in manures and their application on the soil surface, which poses a risk for nutrient dispersion into the environment. Long-term N-based manure application also impacts the apparent nutrient recovery (ANR) by crops and, hence, the crop quality. Our objective was to monitor changes in soil quality and to measure nutrient recovery from N-based organic fertilization in a Brazilian agroecosystem. A long-term experiment was established in May 2004 on Typic Hapludalf soil in Southern Brazil. The experiment comprised two periods: 2004–2009 and 2009–2020. The treatments were unfertilized (control), pig slurry, pig deep litter (swine manure and rice husk), cattle slurry, and mineral fertilizer (urea, triple superphosphate, and K chloride). Grain and cover crops were grown. The maize grain yield and oat biomass were used as indicators of productivity. The application of cattle slurry, pig deep litter, and pig slurry increased the grain production by 20% on average compared to mineral fertilization. Organic manuring increased the soil pH by up to one unit, while urea acidified the soil. The highest crop yields were obtained with pig deep litter, which increased the levels of P, K, Ca, Mg, and C in the soil test. Pig deep litter showed the highest N-ANR for the aboveground part of the plants. The ANRs for P, K, Ca, and Mg were also highest when pig slurry had been applied. The ANR values for the micronutrients varied widely among the organic sources but indicated large marginal offtake gains compared to mineral fertilization. The N-based fertilization with animal manures increased the rate of nutrient uptake by plants but led to an accumulation of nutrients in the soil, threatening the sustainability of the system. Manure applications must be monitored regularly to avoid the accumulation of nutrients that could impair the soil quality and become an environmental problem in the future.

Can Dairy Slurry Application to Stubble, without Incorporation into the Soil, Be Sustainable?

“…In contrast to the mineral fertilizers, dairy slurry supplies simultaneously several nutrients ( Table 5 ) that can contribute to the increased crop yield. However, unlike what is reported in long-term experiments [ 46 , 59 ], our results showed that there were no significant differences in soil P, K, Ca, Mg and Na levels between mineral fertilizer and dairy slurry-based treatments. As P and K inputs were levelled among the treatments, the absence of differences was already expected.…”

“…Among the strategies evaluated, ADS was the one that presented the ANR values closest to MB, MS and IN, thus showing its potential to replace them when applied to stubble-covered soils, without incorporation into the soil. Greater nutrient use efficiency is commonly related to the greater nutrient availability in the soil and at the same time, to the lower nutrient losses such as gas emissions and leachate [ 45 , 46 ]. MS, MB, ADS and IN led to the highest values of N-ANR, significantly superior to RDS T16.…”

“…The acidification ability to dissolve the slurry inorganic P could lead to higher P recovery and P-ANR, probably the P uptake was impaired as an effect of the soil buffer capacity as well as the high p sorption capacity [ 56 ]. In addition, the soil sorption capacity and the relatively low P requirement of ryegrass [ 57 ] appear to be the main reasons why P-ANR was lower than N-ANR [ 46 ]. The apparent K recovery efficiency was similar among the treatments, likely because the K input was levelled among the treatments.…”

The Potential of Pig Sludge Fertilizer for Some Pasture Agricultural Lands’ Improvement: Case Study in Timiș County, Romania

“…Pig slurry and pig deep litter (swine manure and rice husk), tested with other organic and mineral fertilizers, in a long experiment (2004−2020), led to an increase in soil pH by up to one unit, increasing the C content of the soil, and the level of mineral elements in the soil (P, K, Ca, Mg) [45].…”

Perceived determinants of maize production output among small-scale maize producers in Anambra State, Nigeria

“…The result conforms with Asfaw (2022) [4] who reported that poultry manure unlike chemicals and other organic fertilizers, added organic matter to the soil which improved soil composition, nutrient retention, aeration, soil moisture-holding capacity, and water infiltration. Also, Ferreira, Ceretta, Lourenzi, De-Conti, Marchezan, Girotto, et al, (2022) [5] opined that animal manure significantly increases soil moisture, as well as soil compaction, which results to increase in soil moisture and water retention capacity. On the other hand, the amount of fertilizer used was positive and statistically significant at 1% level, which agrees with the "apriori" expectation.…”