Organic fertilization in nectarine (Prunus persica var. nucipersica) orchard combines nutrient management and pollution impact

Abstract

Recycled organic fertilizers may be used to replace chemical source of nutrients; however, some nutrients such as nitrogen and heavy metals released by mineralization can become potential pollutants. The objective of this experiment was to compare, over a 3-year-period of time, the effectiveness of two organic fertilizers (cow manure and compost) with a traditional mineral fertilizer on soil fertility, tree nutritional status, heavy metal concentration in soil and plant in a mature nectarine orchard. Trees were subjected, since their plantation (made in 2001) to the following treatments: (1) mineral fertilization (including nitrogen at 130 kg ha -1 year -1 );(2) cow manure (5 t DW year -1 ha -1 ); (3) compost (5 t DW year -1 ha -1 ). Soil organic matter and total nitrogen concentration increased as a consequence of compost application. Soil nitrate concentration was increased by mineral fertilizer and compost applications. In summer, macro and micro nutrient concentrations in leaves were not affected by treatments with the exception of N that was increased by mineral fertilization. At the end of the season, leaf N, K and Zn were remobilized to storage organs, while Ca, Mg, Cu, Fe and Mn accumulated in abscised leaves and returned to the soil, with no differences among treatments. Nitrogen and K were found principally in fruit flesh. With the exception of Cu and Zn, the concentration of heavy metals in leaves and fruits was below detection limits. Total and DTPA-extractable heavy metals in soil were not increased by organic fertilization if compared with mineral fertilizer.

Animal Manure as Fertilizer: Changes in Soil Attributes, Productivity and Food Composition

“…In addition, the carboxyl and phenolic functional groups, proper of organic matter, form stable complexes with metals, therefore the addition of organic material to the soil may lead to a fixation of metals and decrease in their availability for root uptake. Similar results were found in a trial on nectarine tree supplied with cow manure, municipal solid waste compost or mineral fertilizer that showed a decreased of Pb soil accumulation when cow manure was applied and no effect on heavy metal accumulation in fruit (Baldi et al, 2016). It is possible that organic matter promoted the formation of soluble organic form of Pb, that moved to the deeper soil profiles outside the root volume.…”

Use of In Situ Soil Solution Electric Conductivity to Evaluate Mineral N in Commercial Orchards: Preliminary Results

“…In the soil of the Po Valley, in northern Italy, mineral N is mainly comprised of NO 3 − -N, since NH 4 + -N oxidizes rapidly [16]. As a result, the mineral-N:NO 3 − -N ratio is almost steady, and only water soluble NO 3 − -N is commonly detected for fertilization management [17]. During the growing season, the optimal NO 3 − -N concentration ranges between 5-20 mg kg −1 [18,19].…”

Fertilizer Potential of Organic-Based Soil Amendments on cv. Sangiovese (V. vinifera L.) Vines: Preliminary Results

“…As for woody plants [8,9], the effects of compost on grapevine growth, yield, berry composition [10,11], and on changes induced on soil chemical, biological, and physical properties [12,13] have been widely examined. Whereas inorganic fertilizers are promptly available for plants, organic amendments decompose gradually, mineralizing nutrients over time, and consequently supplying plants with elements during the whole growing season [14].…”