ABSTRACT

In the present investigation, an attempt was made to determine the direct effects of fertilizers on various soil properties like acidification, organic matter content, the content of essential and toxic trace metals in soils and food grains under long term (>25 years) fertilizer experiment. Soil and plant samples were collected from Bengaluru center of All India Coordinated Research Project on Long-Term Fertilizer Experimental site in the sub-regions AESR 8.1 of India, with the treatments e.g. control, 100% N, 100% NP, 100% NPK, 150% NPK, 100% NPK + Lime, 100% NPK+ farmyard manure (FYM) at 0 to 60 cm depth with an interval of 15 cm. Laboratory analysis was conducted to know the vertical distribution of heavy metals and micronutrient cations in soil and plant produce by following the standard method. The DTPA soil Zn remained unchanged with the higher rates of N application, i.e. 100% N. There was very little effect of N, NP, and NPK application on the buildup of DTPA-able Zn, Fe, Mn, and Cu content in both the soils. However, the application of NPK + FYM showed a buildup in comparison to control for Fe 10 mg kg⁻¹, Mn 18 mg kg⁻¹, Zn 1.23 mg kg⁻¹, and Cu 0.84 mg kg⁻¹ in soil. Continuous fertilizer application contributed a meager amount accumulation of Cd, Pb, Ni, Co, and Cr in the soil under the finger millet – maize cropping sequence. The estimation of heavy metals in food grains, supposed to come from fertilizers, lime materials applied in soil was also of our concern. All the cited heavy metals were present in the maize and finger-millet grains. Risk assessment to human health (Hazard Quotient, HQ) for the intake of heavy metals through consumption of contaminated food grains was computed and observed that the values of ‘HQ’ for all the crops were far less than unity (<1) and safe for the consumers.

摘要

在本研究中，尝试确定肥料在长期（> 25年）试验下对酸碱度，有机质含量，土壤和粮食中必需和有毒微量金属含量等各种土壤特性的直接影响。 。土壤和植物样品是从印度AESR 8.1分区域的长期肥料实验站点全印度协调研究项目的班加罗尔中心采集的，采用了对照，100％N，100％NP，100％NPK， 150％NPK，100％NPK +石灰，100％NPK +农家肥（FYM），深度为0至60 cm，间隔为15 cm。按照标准方法进行了实验室分析，以了解土壤和植物产品中重金属和微量营养素阳离子的垂直分布。氮肥施用率较高，即100％氮时，DTPA土壤中的锌保持不变。氮，磷和氮磷钾的施用对可施用DTPA的锌，铁，锰和铜含量的影响很小。土壤。但是，NPK + FYM的施用与铁10 mg kg的对照相比显示出堆积^-1，土壤中的Mn 18 mg kg ^-1，Zn 1.23 mg kg ^-1和Cu 0.84 mg kg ^-1。在小米－玉米种植顺序下，连续施用肥料有助于土壤中Cd，Pb，Ni，Co和Cr的少量积累。估计食物中的重金属估计应该来自化肥，土壤中使用的石灰材料也引起了我们的关注。所有引用的重金属都存在于玉米和小米谷粒中。计算了通过食用受污染的粮食谷物摄入重金属对人体健康的风险评估（危险商，HQ），并观察到所有作物的“ HQ”值均远低于统一值（<1），并且对于人类来说是安全的消费者。