Yassine Gueroui

Sustainability is a major challenge for global food systems, particularly in the context of food loss and waste. Approximately one-third of food produced worldwide (1.3 billion tons annually) is lost or wasted, contributing to 8–10% of global greenhouse gas emissions, with a large share occurring during post-harvest handling and food processing. These stages generate by-products such as shells, skins, pulp, stems, and seeds, which can account for 30–50% of raw materials. Although often discarded, these residues are rich in valuable bioactive compounds, including phenolics, peptides, carotenoids, fibers, secondary metabolites, minerals, amino acids, and vitamins. This review emphasizes the valorization of agrifood by-products as a pathway toward sustainability and the achievement of the Sustainable Development Goals (SDGs). It encompasses extraction methods, characterization, and potential uses of such active compounds in the food, pharmaceutical, packaging, and cosmetic sectors. Moreover, it examines the interaction between valuing agrifood by-products and key SDGs like eliminating hunger (SDG 2), ensuring good health and well-being (SDG 3), promoting affordable and clean energy (SDG 7), promoting economic growth and decent work (SDG 8), ensuring responsible consumption and production (SDG 12), and tackling climate action (SDG 13). These approaches have high potential to improve food security and economic sustainability of the world’s food systems.

Approximately a third (1.3 billion tons) of the food that is generated globally is lost each year, and it accounts for over 20% of the global greenhouse gas emissions. Most of this loss is by-products generated during post-harvest and food processing, which account for 30–50% of raw materials, including shells, skins, pulp, stems, and seeds. While generally wasted, such by-products contain precious bioactive molecules such as phenolic acids, bioactive peptides, carotenoids, fibers, and secondary metabolites (e.g., terpenes, polyphenols, alkaloids) and minerals, amino acids, and vitamins. This review outlines how these high value agrifood by-products can be utilized towards achieving sustainable development goals (SDGs). It encompasses extraction methods, characterization, and potential uses of such active compounds in the food, pharmaceutical, packaging, and cosmetic sectors. Moreover, it examines the interaction between valuing agrifood by-products and key SDGs like eliminating hunger (SDG 2), ensuring good health and well-being (SDG 3), promoting affordable and clean energy (SDG 7), promoting economic growth and decent work (SDG 8), ensuring responsible consumption and production (SDG 12), and tackling climate action (SDG 13). These approaches have high potential to improve food security and economic sustainability of the world's food systems.

This study evaluates the performance of machine learning (ML) algorithms in predicting the Irrigation Water Quality Index (IWQI) for irrigation in the Bouhamdane Basin, with XGBoost ML-2 emerging as the most accurate model (R2 = 0.93, root mean square error (RMSE) = 0.047). Other boosting-based methods like ADABoost ML-4 (R2 = 0.79, RMSE = 0.085) and CatBoost ML-2 (R2 = 0.87, RMSE = 0.065), as well as random forest (RF) ML-2 (R2 = 0.89, RMSE = 0.06), also demonstrate strong predictive capabilities, outperforming linear and support vector regression models. Additionally, voting ensemble models (R2 = 0.90, RMSE = 0.06) highlight the effectiveness of integrating multiple algorithms. The study also analyzes key water quality parameters, revealing variability in irrigation suitability, with some samples posing salinity and sodicity risks (sodium adsorption ratio (SAR) up to 24.509, IWQI as low as 16.86) and others being suitable (IWQI up to 53.80). Overall, the study underscores the significant role of advanced ML techniques in improving water quality assessment for irrigation, offering valuable insights for environmental monitoring and agricultural water management.

In semi-arid and arid regions, groundwater is crucial but fluctuates due to regional factors, usage, and climate. Climate change exacerbates these variations, affecting agriculture, wildlife, and human life, making sustainable management of freshwater resources essential. This study aims to delineate the groundwater potential area in the northeastern part of Algeria, using remote sensing (RS), Geographic Information Systems (GIS), and the Analytical Hierarchy Process (AHP). Thematic layers, including rainfall, lithology, drainage density, geology, land use and land cover (LULC), and slope percentage, were generated. After that, potential groundwater areas within the study region were defined by applying weights to layers and combining them linearly. SWOT (strengths, weaknesses, opportunities, and threats) analysis was used to assess GIS and RS techniques for groundwater potential estimation. Subsequently, prospective zones are classified into four categories with groundwater potential ranging from very high to very low: 30.6% (very high), 44.06% (high), 22.42% (low), and 2.9% (very low). SWOT analysis revealed that RS and GIS techniques can offer accurate, quick, and easy-to-use, data for free (not all the time) concerning groundwater potential estimation covering large areas and permitting repetitive coverage. They offer several opportunities, such as the development of specific training programs and the establishment of new legislation to safeguard groundwater resources. However, climate change, limited funding, restricted satellite data access, and inadequate legislation are key barriers to the development and implementation of RS and GIS techniques. These findings underscore the potential of RS and GIS data to support more efficient and sustainable groundwater management.

Small ruminants, such as sheep (Ovisaries) and goats (Capra hircus), contribute to approximately 475 million metric tons of carbon dioxide equivalent (MtCO₂e) greenhouse gas (GHG) emissions, accounting for approximately 6.5% of the global emissions in the agriculture sector. Crop residues, silage, grasses, hay, browse, plant leaves, shrubs, agro-industrial by-products, poultry litter, and other alternative feed sources are frequently utilized for small ruminant production. The use of these valuable alternative feeds can significantly improve animal productivity and reduce carbon footprints and GHG fluxes, making it both environmentally friendly and cost-effective. Additionally, these alternative feeds possess antioxidant, antimicrobial, and antiseptic properties that can enhance the quality of the meat and milk produced. By impacting the bacteria involved in ruminal biohydrogenation, alternative feeds can reduce methane emissions and contribute to a decrease in the carbon footprint. Overall, the use of alternative feed sources for small ruminants generally improves their apparent nutrient digestibility and productivity, and has an impact on the production of greenhouse gases, especially methane. Finally, this review recommends evaluating the economic analysis of reducing methane emissions in small ruminants by utilizing different feed sources and feeding techniques.

The present study aims to evaluate the groundwater quality in an area characterized by significant human anthropic activities within the upper Seybouse. In order to assess the quality, a total of 20 samples were analyzed to identify the chemical and bacteriological composition of the water, its variations, and their potential impacts on the environment and human health. The results revealed concentrations of the chemical and bacteriological elements exceeding the WHO standards, with high levels of electrical conductivity (EC) (peak = 4210 μS/cm), Ca²⁺ (peak = 340.68 mg/L), Na⁺ (peak = 360 mg/L), HCO₃⁻ (peak = 287 mg/L), Cl⁻ (peak = 542 mg/L), SO₄²⁻ (peak = 687 mg/L), NO₃⁻ (pek = 65.91 mg/L), fecal coliforms (FC) (peak = 160 UFC/mL), fecal Streptococcus (FS) (peak = 43 UFC/mL), and Clostridium perfringens (CP) (peak = 29 UFC/mL). Within the basin, two different facies have been identified: Cl-SO₄-Na type and Cl-SO₄-Ca type. The calculated Water Quality Index (WQI) indicates that none of the groundwater samples are suitable for drinking or human consumption. The detection of pathogenic microorganisms through diverse molecular methods has revealed the existence of eight distinct species, encompassing pathogenic strains that can affect human health. Moreover, the dissolution of geologic formations can influence the water’s chemistry. In this region, groundwater pollution seems to be influenced by anthropogenic and agricultural factors such as fertilizer application, irrigation practices, and the release of domestic sewage.

Algerian indigenous cattle breeds are well adapted to the harsh local arid and semi-arid environments. This study aims to summarize livestock practices, milk quality, and discuss the potential of local cattle breeds to maintain production capacity in the face of global warming conditions. A total of 175 smallholder farmers who practice the breeding of the Algerian local cattle breed were interviewed using a formal questionnaire. Following that, 122 milk samples were collected for physicochemical and bacteriological analyses. Climate data variability in the study area was evaluated. Results reveal that between 1980 and 2018, the average annual temperature rose by 0.3 ± 0.001 °C per year. Predictions suggest that by 2081 to 2100, temperatures could increase by 1.18°C under SSP1-2.6, 2.33°C under SSP2-4.5, and 4.59°C under SSP5-8.5. In the same period from 1980 to 2018, annual precipitation decreased by -0.99 ± 0.24 mm per year. Projections indicate a further decline of 22.5 mm for SSP1-2.6, 44.4 mm for SSP2-4.5, and 95.2 mm for SSP5-8.5 from 1980-2000 to 2081-2100. These changes in temperature and precipitation coincided with an expansion of cropland, which increased by 90.3% from 1992 to 2005. Conversely, pasture areas decreased by 53.7% between 1993 and 2009. A socio-demographic survey revealed that breeders have a low educational level (39.4% are unlettered). They own a small herd (6.84 ± 8.66 cattle). Moreover, the average daily milk production was 4.13 ± 2.12 Liters/cow, with acceptable physicochemical quality but poor bacteriological quality. Considering the climate change vulnerability of the study area, we can conclude that the exploitation of local breeds seems to be the best adaptation strategy to climate change effects. Conservation programs for local breeds can enhance biodiversity and ecosystem balance. Concurrently, genetic improvement programs have the potential to boost productivity and profitability, making substantial contributions to social equity and local economies.

The indigenous cattle populations are threatened by extinction in many countries of the Mediterranean area. The objective of this study is the analysis of local cattle breeds’ production systems in Algeria, Greece, and Tunisia and the identification of their future challenges and opportunities. A total of 385 surveys were conducted in these study areas: central and northern Greece (43); northern and northwestern Tunisia (167), and northeastern Algeria (175). Data collected concerned socio-economic parameters as well as the production system’s functionality, constraints, and opportunities. Results revealed an average farmers’ age of 52.6 years old. The illiteracy rate is high, especially in Algeria (39%) and Tunisia (44%), where the farm size is relatively small with an average of 14 and four animals per farm, respectively. In Greece, much higher numbers were recorded (89 animals/farm). The average cultivated feedstuffs’ area is larger in Greece (12.07 ha) and smaller in Algeria and Tunisia (6.11 and 2.88 ha, respectively). Feeding resources are based on rangelands. Farming systems are traditional extensive and complemented when needed. Milk and meat marketing vary throughout countries and are not well valorized. The main constraints are high feeding costs, low milk and meat prices, and absence of labeling. Local and local-crossbred bovine populations could be valorized based on their good adaptation criteria when applying convenient genetic and development strategies.

In order to deal with the effects of globalization, urbanization, increase in world population, global warming, and climate change; and according to the Sustainable Development Goals (SDG) 2 targets, which aim to end hunger, achieve food security and improved nutrition and promote sustainable agriculture, it is urgently needed to transform our agriculture and livestock farming systems by taking into account the environmental considerations. The Breeding and management practices of indigenous bovine breeds: Solutions towards a sustainable future (BOVISOL) project is a scientific cooperation between three Mediterranean countries (Greece, Tunisia and Algeria) supported and funded by the European Commission under the European Research Area Networks (ERA-NET) scheme of the 7th Framework Programme. This project has been formed around the hypothesis that the local bovine breeds must be preserved since they possess a valuable genetic pool, and they are a part of the landscape and the biodiversity of rural areas. Moreover, their products (milk, cheese, meat, etc.) could contribute significantly to the local economies as they could easily be associated with recent food trends like “local” and “slow food”, which are considered today, as, not only a mean of nutrition, but also a way of living and a part of people’s identity. BOVISOL project aims to: (i) identify the local breeds and populations in a national level, (ii) describe the existing farm and breeding practices, (iii) analyze the quality of the main local animal products, (iv) propose solutions that will promote the sustainability of the traditional farming systems, especially nowadays that climate change proposes new challenges on animal production, and (v) disseminate the solutions on all the levels of the sector (farmers, scientists, local communities, governmental agencies).