Abstract

In this study, we investigate the effect of nitrogen fertilizer application rates with and without phosphorus-loaded biochar (BCP) on the productivity of tomato (Solanum lycopersicum cv GS) planted on a contaminated soil based on pot and incubation experiments. The release kinetic of toxic metals as affected by BCP was also investigated. BCP at rate of 2% (w/w) and nitrogen levels (250 and 500 mg N kg⁻¹) were added to sandy loam soil polluted with Cd, Pb, Zn, and Cu. The experiment consisted of five treatments including: Control (C), nitrogen a rate of 250 (N₂₅₀), or 500 mg kg (N₅₀₀), BCP + N₂₅₀, and BCP + N₅₀₀. Maximum tomato growth was achieved in the soil that was treated with BCP + N₅₀₀, followed by BCP + N₂₅₀, while lowest one was observed in the control. Tomato yield as affected by the BCP and N-fertilization was in the descending order: BCP + N₅₀₀ > BCP + N₂₅₀ > N_{500 =} N₂₅₀ > C. The addition of N₂₅₀, N₅₀₀, BCP + N₂₅₀, and BCP + N₅₀₀ increased the fruit yield by 24, 31, 35, 58% in comparison with the control. Levels of Zn, Cu, and Pb in tomato fruit was in the descending order: N₅₀₀> N₂₅₀ > C > BCP + N₅₀₀ > BCP + N₂₅₀. The combined application of BCP and N-fertilization augmented the availability and uptake of essential nutrients and effectively reduced those of toxic ones. The addition of BCP + N₂₅₀ decreased Zn, Cu, Cd, and Pb content in fruit of tomato by 16, 10, 54, 54, and 58%, respectively, compared to the control soil, while these decreases were 13, 16, 60, 60, and 72% in the case of BCP + N₅₀₀. BCP succeeded significantly in reducing the release of toxic chemicals, which ultimately may restrict the transfer of toxic chemical to the food chain solution.

Novelty statement Tomato grown on metal-contaminated soils contains high levels of toxic metals. Phosphorus-loaded biochar (BCP) reduced the negative effects of high inorganic-N rates by reducing the release of toxic metals to the soil solution. BCP enhanced the soil quality indicators and increased the soil microbe’s activity.

摘要

在这项研究中，我们基于盆栽和孵化实验研究了氮肥施用量在有和没有载磷生物炭 (BCP) 的情况下对种植在污染土壤上的番茄 ( Solanum lycopersicum cv GS) 生产力的影响。还研究了受 BCP 影响的有毒金属的释放动力学。将 2% (w/w) 的 BCP 和氮水平（250 和 500 mg N kg ^-1）添加到被 Cd、Pb、Zn 和 Cu 污染的沙壤土中。该实验由五种处理组成，包括：对照 (C)、氮肥 250 (N ₂₅₀ ) 或 500 mg kg (N ₅₀₀ )、BCP + N ₂₅₀和 BCP + N ₅₀₀. 在用 BCP + N ₅₀₀处理的土壤中实现了最大的番茄生长，其次是 BCP + N ₂₅₀，而在对照中观察到最低的一个。BCP和N施肥对番茄产量的影响依次为：BCP + N ₅₀₀ > BCP + N ₂₅₀ > N _{500 =} N ₂₅₀ > C。添加N ₂₅₀、N ₅₀₀、BCP + N ₂₅₀和BCP + N ₅₀₀比对照提高果实产量24%、31%、35%、58%。番茄果实中Zn、Cu、Pb含量由高到低依次为：N ₅₀₀ > N ₂₅₀ > C > BCP + N ₅₀₀> BCP + N ₂₅₀。BCP和N施肥的联合应用增加了必需营养素的可用性和吸收，并有效地减少了有毒营养素。与对照土壤相比，添加 BCP + N ₂₅₀使番茄果实中 Zn、Cu、Cd 和 Pb 的含量分别降低了 16%、10%、54%、54% 和 58%，而这些降低了 13%、16%、在 BCP + N ₅₀₀的情况下为 60、60 和 72% 。BCP 成功地显着减少了有毒化学物质的释放，这最终可能会限制有毒化学物质向食物链溶液的转移。

新颖性声明在受金属污染的土壤上种植的番茄含有大量有毒金属。负载磷的生物炭 (BCP) 通过减少有毒金属释放到土壤溶液中来降低高无机氮含量的负面影响。BCP提高了土壤质量指标，增加了土壤微生物的活性。