Towards Achieving Food Security in Nigeria: A Fuzzy Comprehensive Assessment of Heavy Metals Contamination in Organic Fertilizers

In the quest towards achieving the Zero hunger agenda of the sustainable development goals by 2030, the utilization of organic fertilizers, for soil amendment purposes, has been posited as a feasible alternative for overcoming the negative impacts of inorganic fertilizers. Despite its manifold benefits, the use of untreated and improperly treated organic materials in agricultural production is however capable of introducing toxic metals in the soil-plant systems causing health and agro-environmental impacts. In this study, available organic fertilizers use by Nigerian farmers were selected and analyzed for nutrient values and most importantly, heavy metal contamination. The degree of contamination in each sample was modeled using fuzzy comprehensive assessment. The manure samples possessed optimum nutritional values; the nitrogen, phosphate, and potash contents ranged from 0.91 – 7.44, 0.06 – 1.61, 0.14 – 0.58% respectively. The fuzzy algorithm results categorized all the organic fertilizers as pristine, with a membership degree ranging from 35 to 99%. However, an excessive level of toxic contamination, with a membership function between 3 to 33% was observed. The major contaminants were identified as Zn, Cr, and Cd with an individual contribution of 16, 29, and 33% respectively. Adequate remediation techniques and good management practices that reduce the concentration of heavy metals in the organic fertilizers especially that of Zn, Cr, and Cd, should therefore be promoted among the producers and users of these soil improvers in Nigeria.

A multi-level fuzzy comprehensive assessment for supply chain risks

Potential supply chain risks are one of the hidden dangers that may undermine the reliable and stable operation of enterprises. Due to the practicality and complexity of supply chain risk management, the field has attracted wide attention from researchers. The urgent problems of supply chain management at present include how to help enterprises analyze and identify supply chain risk factors, predict and control the potential risks, and provide the corresponding preventive measures for various risks. There are many assessment methods in the research process of supply chain risks. In this paper, a multi-level fuzzy comprehensive assessment method is adopted. Based on the current risk status of the traffic enterprises in our country, an attempt is made to apply the multi-level fuzzy comprehensive assessment method to risk assessment. The main risk factors faced by traffic enterprises in the supply chain are analyzed to obtain the assessment results, which can provide ideas for further research in the future.

Improved Principal Component-Fuzzy Comprehensive Assessment Coupling Model for Urban River Water Quality: A Case Study in Chongqing, China

An improved principal component-fuzzy comprehensive assessment coupling model for urban river water quality is proposed, which fully considers the influence of water quality and quantity. This model can not only choose the key indexes, but also specify the spatial variation and class of water quality. This proposed model was used to assess the water quality of the Qingshui and Fenghuang streams in Chongqing, China. Data of twelve indexes used in the assessment were collected from 17 monitoring points. The assessment results show that the key indexes include TN, TP, NH3-N, CODcr, pH, DO and velocity. Water quality of 14 monitoring points is classified as class Bad V, and that of the remaining points is class V. Mainly affected by the deposition of garbage and discharge of domestic sewage, water quality of the midstream is the worst. The upstream is mainly influenced by farmland non-point source pollution and rural domestic sewage pollution. The downstream is close to the scenic area, and environmental control measures such as river dredging and artificial aeration are regularly carried out. The water quality of it is the best. The results provide valuable information that allow local environmental departments to discover the source of pollutant and formulate water resource management strategies.

Synthetic evaluation of integrated energy system based on AHP- fuzzy comprehensive assessment method

Integrated energy system (IES) is an essential ingredient of energy reform. The construction of IES can promote the coupling utilization of multiple energy sources, and improve the reliability and flexibility of energy system. Based on amounts of literature study and experts’ recommendations, 9 first- class indexes, 13 second-class indexes and 11 third-class indexes are confirmed to assess the integrated energy system from three dimensions of technology, economy, and environmental protection. Analytic Hierarchy Process (AHP) and fuzzy comprehensive assessment method are adopted to assess the overall quality of chosen integrated energy system. An industrial park is chosen to be an example and examine the evaluation condition of IES.