Suchergebnisse

For decades, non-renewable resources have been the basis of worldwide economic development. The extraction rate of natural resources has increased by 113% since 1990, which has led to overexploitation and generation of vast amounts of waste. For this reason, it is essential that a sustainable development model is adopted—one which makes it possible to produce more food and energy with fewer fossil fuels, low pollutant gas emissions and minimal solid waste. Certain management policies and approaches, such as the strategy of a circular ecocomy or bioeconomy, are oriented towards sustainable production and consumption. The present study focuses on the importance of intensive horticulture in the Mediterranean region, specifically in the province of Almería (Spain). After having conducted a study of the main crops in this area, it was determined that the waste biomass generated presented strong potential for exploitation. With the proper regulatory framework, which promotes and prioritises the circularity of agricultural waste, there are several opportunities for improving the current waste management model. In the same way, the results of the economic evaluation demonstrate that the alternative of self-management of waste biomass is profitable, specifically from tomato crops. Compost and green fertilizer production also prove to be a key strategy in the transition towards a more circular and sustainable agricultural production model. As for the said transition, government support is vital in terms of carrying out awareness campaigns and training activities and providing financing for Research and Development (R&D).

Abstract
Background
Waste disposal is an activity that pollutes the environment. The European Union has developed different legislative measures which are based on the circular economy (CE) to avoid this negative externality. The management of agricultural packaging (fertilizers and phytosanitary products) is carried out through Collective Deposit, Return, and Refund Systems (CDRRS). New regulations on waste tax the consumption of non-recyclable plastic in packaging, but also reward the use of plastic by-products from packaging. The administrations recommend using biodegradable plastic in the means of production, as well as establishing a traceability system (TS) to control the proper management of all the generated waste. The proposed measures can affect producer cost accounts. This work aimed to identify and evaluate the existing agricultural packaging management system in Spain. It also studied the influence of the price of a barrel of oil, crop surface, irrigation regime, and the type of subsectors on CDRRS, and quantified the impact of the latest fiscal measures and initiatives proposed by Spanish administrations.

Results
The generation of agricultural packaging is influenced by variables including the cultivated area, irrigation regime, and agricultural subsector. The price of a barrel of oil directly influences the current by-product utilization system. Using biodegradable plastic or implementing a TS can increase production costs by up to 9.80%. The current system of subsidies to producers can soften the economic impact caused by the additional cost of biodegradable plastic (4.03%), but no subsidies have been foreseen to encourage the use of environmentally friendly alternatives.

Conclusions
Findings indicate that public administrations should be guided by the specific characteristics of the different agricultural systems when defining regulations on agricultural waste management. The fixed rate in the current system of subsidies for using plastic by-products obtained from packaging should be substituted for a variable rate. Transferring powers to autonomous communities to define by-products may lead to heterogeneity in the Spanish territory. New measures derived from the recent environmental agreements to comply with the 2030 Agenda will increase production costs even after considering the current aid scheme. The subsidy coefficient should be increased to 80% of the purchase invoice.

In recent decades, ecosystems have suffered diverse environmental impacts caused by anthropogenic activities, including the dumping of plastic waste. This situation has prompted the European Union to introduce a new policy based on the circular economy. In this study, the present state and future perspectives on the generation and treatment of plastic waste in the intensive agriculture of Almeria (Spain) are analyzed. This activity generates 1503.6 kg·ha−1·year−1, on average, of plastic waste with an approximate treatment cost of 0.25 €/kg. The present study shows that the volume of plastic waste from intensive agriculture in Almeria is constantly increasing (48,948.2 tons in 2020/21) and it is suggested that the current management system does not meet the needs of the sector. Although it presents great opportunities for improvement under the framework of the circular economy. Furthermore, this work reports a direct relationship between the price of the raw materials needed for the production of plastic and the volume of recycled plastics. For this reason, it would be advisable for the administration to consider the implementation of a tax rebate system for the sector and specifically when the petroleum derivatives used to manufacture plastic are less expensive, and the recycling option is not so attractive.

AbstractBackgroundThe agricultural and construction sectors demand enormous amounts of natural resources and generate environmental impacts that negatively affect ecosystems. One of the main problems is the generation and inadequate management of waste. For this reason, under the approaches of the new sustainable and circular models, waste valorization has been prioritised as a strategy for advancing towards the sustainability of production systems. This research aims to carry out a general analysis of Agricultural Waste Biomass (AWB) in the production of bio-based products for the construction sector. Bibliometric techniques were applied for the general analysis of the scientific production obtained from Scopus. A systematic review identified the main research approaches. In addition, European projects were reviewed to assess the practical application. This study is novel and provides relevant contributions to new trends in the valorisation of AWB in the building sector and the sustainability benefits. For policymakers, it is a source of information on the contribution of new policies to scientific advances and the aspects that need to be strengthened to improve sustainable and circular practices in both sectors.ResultsThe results show that 74% of the research has been published within the last 5 years. Regarding the main types of AWBs, rice husk ash and sugar cane bagasse ash are the most commonly used in manufacturing a wide variety of bio-based building products. Cement, concrete and bricks are the main bio-based products obtained from AWB. However, a new approach to utilisation was identified in road construction.ConclusionsThe findings indicate that the AWB is an important resource with great potential for the construction sector. Similarly, that policies on sustainable and circular development have driven scientific progress on new alternatives for the valorisation of AWB to improve sustainability in the construction sector. Although the practical application has also been driven through European projects, development at this level is still low. Therefore, it is necessary to strengthen partnerships between these two sectors and improve government strategies on sustainability and circularity to overcome existing constraints.