The valorization of plant genetic resources and their direct use in local markets can make a significant contribution to the preservation of agrobiodiversity, while also contributing to the sustainability of rural communities. Indeed, plant genetic resources are a precious source of genes, and they represent an important crop heritage for the quality and sensory characteristics that are required by both farmers and consumers. However, an efficient strategy of agrobiodiversity conservation is strictly connected to product marketability and to consumer preferences. In the present study, choice experiments that involved 920 consumers were carried out to determine their willingness to pay for ancient local tomato varieties (landraces) rather than commercial varieties based on their preferences, and to determine how much they valued these products. The results obtained indicate that consumers are willing to pay premium prices for ancient local tomato varieties (an additional €0.90 kg−1), thus demonstrating their increasing attention to sustainable food and the willingness to contribute to agrobiodiversity conservation and enhancement. These results provide the basis for planning strategies and programs to support the cultivation of these landraces and the development of regional and national markets to acknowledge their characteristics, which will considerably increase the effectiveness and efficiency of conservation strategies.

Organic, grassfed (OGF) dairy, which requires higher pasture and forage dry matter intake compared with standard organic dairy practices, is unique both in its management needs and in production challenges. The OGF dairy sector is rapidly growing, with the expansion of this industry outpacing other dairy sectors. There is a lack of research outlining OGF dairy production practices, producer-identified research needs or social factors that affect OGF systems. The objectives of this study were to, with a group of OGF dairy producers, (1) assess information regarding current production practices and producer knowledge, and (2) identify agronomic and social factors that may influence milk production on OGF farms across the United States. A mail survey, focused on demographics, forage and animal management, knowledge, and satisfaction of their farm, was developed and distributed in 2019, with 167 responses (47% response rate). The majority of producers indicated they belonged to the plain, or Amish-Mennonite, community. Milk production was greater on farms that had Holstein cattle, as compared to farms with Jerseys and mixed breeds, and employed intensive pasture rotation. Furthermore, most producers reported the use of supplements such as molasses and kelp meal, which can improve milk production, but also increase feed costs. Producers who indicated that they were at least satisfied with their milk production also reported high levels of knowledge of grazing management and cow reproductive performance. Comparison of response data from plain/non-plain respondents revealed that those that did not identify as plain were more likely to utilize certain government programs, had different priorities and utilized technology more frequently. Based on these results, more research exploring financial and production benchmarks, effective communication strategies to reach OGF producers and methods to improve cattle production through improved forage quality is needed.

Rapid changes in economic, environmental and social conditions generate both problems and opportunities in agriculture. The cycle from problem identification through discovery of potential solutions is lengthy. The objective of this study was to use collaborative methods to speed the cycle of discovery in sustainable organic strawberry (Fragaria × ananassa) production systems in the southeastern USA. This method, stakeholder-driven adaptive research (SDAR), combines farmers' experiential knowledge with scientists' experimental knowledge to develop rigorous research design collectively. Farmers evaluated our biological research and co-designed research experiments with scientists. Farmers and other stakeholders (1) evaluated on-station experiments individually and then made recommendations as a group, (2) served as advisory council members to direct our goals and objectives, and (3) conducted farmer field trials where they implemented aspects of our on-station experiments under their management regimes. The results eliminated potential solutions that were not feasible, ineffective or too costly for farmers to adopt. Key results included eliminating treatments using high tunnel systems altogether on one field trial on a University of Florida (UF) research facility, adding a leguminous cover crop mix treatment, adding companion planting, and eliminating strawberry cultivars Strawberry Festival and Florida Beauty from our research trials. Our proposed methodology allows farmers and other stakeholders to inform the biological research from design through dissemination to reduce the time needed to create research products in an era of rapid bio-physical, social and economic change. Accelerating the discovery cycle could significantly improve our ability to identify and address threats to the USA and global food and fiber production system.

The choice between organic and inorganic farming is an exciting debate in scholarly literature. A large number of studies has enriched the discussion. However, this particular study adds to this debate in unique ways. This study uses a hybrid model based on analytic hierarchy process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), a methodological contribution to the debate of organic and inorganic farming by using multicriteria decision analysis. Also, this study uses several conflicting criteria (such as health benefits, environmental benefits, soil fertility, consumer awareness, etc.) that have not been combined in a single research study earlier to consider the choice of organic and inorganic farming. The study is based on a questionnaire survey undertaken by consumers, farmers and agriculture experts. After the application of the AHP-TOPSIS based hybrid model, several interesting results have been founded that have important policy implications for farming in Pakistan and other developing countries.

Positive relationships between plant species diversity, soil microbial function and nutrient cycling have been well documented in natural systems, and these relationships have the potential to improve the production and sustainability of agroecosystems. Our objectives were to study the long-term effects of planted species composition and nitrogen (N) fertilization on soil microbial biomass C, extracellular enzyme activity, changes in total soil C, soil fertility and aboveground biomass yield in mixtures of native prairie species managed with and without N fertilizer for bioenergy production at four sites in Minnesota (MN), USA. Species were sown into mixture treatments and composition was not maintained (i.e., no weeding) throughout the duration of the study. Species mixture treatments at establishment included a switchgrass (Panicum virgatum L.) monoculture (SG), a four-species grass mixture (GM), an eight-species legume/grass mixture (LG) and a 24-species high diversity forb/legume/grass mixture (HD). Species diversity and aboveground productivity were similar for most mixture treatments at final sampling after 11 or 12 years of succession. Despite this homogenization of productivity and diversity throughout the study, the effects of planted species diversity and a decade of succession resulted in some differences in soil variables across species mixture treatments. On a peat soil in Roseau, MN, soil enzyme activities including β-glucosidase (BG), cellobiohydrolase (CBH) and phosphatase (PHOS) were highest in HD compared to GM treatments. On a sandy soil at Becker, MN, total soil C increased in all treatment combinations at the 0–15 and 15–30 cm depth intervals, with SG showing greater increases than HD at the 15–30 cm depth. Final soil pH also varied by species mixture at the Becker and Roseau sites, but differences in treatment comparisons varied by location. Nitrogen fertilization did not affect any response variable alone, but interacted with species mixture treatment to influence PHOS and total soil C at Becker. The inconsistent effects of species mixture and N fertilization on soil biological and chemical properties observed across sites highlight the importance of local soil and climate conditions on bioenergy and ecosystem service provisioning of perennial bioenergy cropping systems.

Despite continuous growth in demand for organic food and farm products, US domestic supply is not keeping pace. Increasing domestic supply requires, in part, that more farms transition to certified organic production. This in turn requires a better understanding of the transition process. This paper reports on a national survey of farmers transitioning to organic certification through participation in the United States Department of Agriculture's (USDA) Natural Resources Conservation Service (NRCS) Environmental Quality Incentives Program Organic Initiative (EQIP-OI). Our analysis focuses on what motivates farmers to undertake transition to organic certification and what obstacles they confront in the process. The survey population included farmers in the midst of the transition process and farmers who began transition but decided not to pursue organic farming, allowing us to compare both groups to farmers who successfully transitioned to certified organic. Because farmers do not control all of the factors that influence their success, we use a ‘spheres of influence’ framework to analyze obstacles at four levels: the farm, local and regional infrastructure, the marketplace and policy. Our results improve our understanding of the transition process and apply to a wide range of stakeholders and service providers who support farmers in different ways, through crop research, infrastructure development, market development and policy.

Legume green manures (GM) are a vital source of nitrogen (N) for many organic grain systems. A common practice among organic growers is to undersow clover into a small grain, harvest the grain crop and terminate the clover stand in late fall by moldboard plowing in preparation for a cash crop the following spring. While fall plowing offers excellent clover kill, growers increasingly seek an alternative termination method that reduces tillage intensity and bare winter soil. This study, performed at two sites in Maine, evaluates three clover termination methods for kill efficacy, winter soil cover, spring soil conditions and N uptake and grain yield and protein of a subsequent test crop of hard red spring wheat (Triticum aestivum L., var. Glenn). Red clover (Trifolium pratense L.) was intercropped with spring barley (Hordeum vulgare L.) and terminated in late fall by moldboard plowing (PL), skim plowing (SK) or undercutting (UC). A control treatment received no clover and was fall plowed. An additional treatment, winterkilled field peas (WK), was evaluated at one site. SK, UC and WK increased soil cover relative to PL, though UC resulted in low clover kill efficacy in a wet spring and is in need of improved design. Grain yield was higher following red clover compared to the no-clover control at one site, but was unaffected by termination method. At one site, grain crude protein was higher following PL than the other treatments, indicating the possibility for more favorable timing of N availability associated with PL.

Organic matter water extract, or so-called ‘tea’, may be used to correct nutrient deficiencies in crops or enhance their defense systems. Such tea mixtures are prepared locally by Mediterranean farmers to offset a multitude of constraints, particularly a scarcity of organic manure or high synthetic input costs. However, the diverse range of tea production and usage practices and farmers' underlying rationales have yet to be thoroughly studied. Yet locally they constitute real alternatives that allow farmers to maintain their income levels while reducing reliance on chemical inputs. The main objective of this study was to gain insight into farmers' rationale and practices regarding the production of homemade dry manure tea (HMT) in North Africa, while also highlighting the benefits perceived by farmers. Nearly 50 interviews with farmers were thus conducted in three irrigated cropping areas in Morocco, Algeria and Tunisia. Our results showed that HMT is widely used in intensified family horticultural cropping systems that usually rely on drip irrigation and chemical fertilization. The analysis of farmers' practices revealed that HMT was generally made from aged manure that was pure or consisted of a mixture of sheep, cow or poultry dung. The production protocol varied in terms of drenching techniques, maceration time, container volume and type, and filtration techniques. Farmers applied the derived tea via the drip irrigation system, regularly or with a limited number of applications. The analysis of farmers' rationales and perceptions regarding HMT clearly highlighted that they felt that these practices played a positive role. HMT was considered to improve vegetative growth, yield and, to a lesser extent, soil properties. These benefits could in turn lead to decreased use of synthetic fertilizers by farmers, while boosting their income. The increased understanding of HMT and the underlying rationales showcased in this study could help scientists better analyze and assess these practices in the future. The findings could also facilitate improvement and wider dissemination of these practices to achieve more sustainable irrigation systems in the intensified irrigated cropping areas that abound in North Africa.

Degradation of crop and grazing lands is a pervasive problem that negatively impacts agricultural productivity and livelihoods of crop-livestock farmers in the Blue Nile basin of Ethiopia. Area enclosure together with a cut and carry livestock feeding system is often advocated as an approach for the regeneration of degraded grazing lands. This paper reports the results of a two-year farmer participatory study conducted to assess the effects of infiltration trenches (ITs) and Chloris gayana Kunth (Rhodes grass; cultivar Masaba; tetraploid; C4 grass species) reseeding on restoration of degraded grazing lands. A split plot design was used with IT as the main plot and C. gayana reseeding as a sub-plot on 28 private grazing plots under enclosure. The results showed that IT alone increased soil moisture content and prolonged the growing period. IT and C. gayana reseeding together significantly (P ≤ 0.05) increased herbage dry matter yield and improved soil chemical properties. The highest mean herbage dry matter yield (21 Mg ha−1 per cut) was recorded for plots treated with IT and reseeded with C. gayana. The higher herbage dry matter yield was attributed to increased soil moisture and the resultant prolonged growing period induced by the trenches coupled with the ability of C. gayana to effectively utilize the retained water. The results suggest that an integrated land management approach involving enclosure, in-situ water conservation and C. gayana reseeding can rapidly increase biomass productivity on degraded grazing lands while also enhancing soil quality with concomitant livelihood benefits for farmers.

During 2015 and 2016, studies were conducted at Absaraka and Dickinson, North Dakota to evaluate the impacts of hemp (applied at 1156 m3 ha−1) and commercial paper mulch, as well as soil-applied biochar (applied at 11.25 m3 ha−1), on weed suppression and strawberry growth during the establishment year, and on weed suppression and strawberry yield during the production year, in a matted row production (MRP) system. During 2015, biochar influenced dry weed biomass only within the hemp mulch, with slightly more weed biomass associated with biochar application compared to zero biochar (3.1 vs 0.4 g m−2), suggesting that biochar may have increased weed germination and/or emergence from beneath hemp mulch. Biochar application also slightly increased soil pH, from 6.9 in non-amended soil to 7.0 in amended soil. Strawberry runner number during 2015 was greater in association with hemp or paper mulch compared to zero mulch (4.5 and 4.9 vs 2.4 runners plant −1, respectively). This result mirrored a similar differential in per berry mass across sites (7.6 and 7.4 vs 6.2 g berry −1 for hemp mulch, paper mulch and zero mulch, respectively). These results may be related to hemp and paper mulch reducing maximum soil temperatures during summer 2015. During the establishment year, both hemp and paper mulch suppressed weeds well compared to zero mulch, although at Absaraka hemp mulch provided slightly better weed suppression than paper mulch. During the production year, both mulches continued to suppress weeds compared to zero mulch at Dickinson. However, at Absaraka, only hemp mulch provided weed suppression compared to zero mulch, possibly because of faster paper degradation caused by greater numbers of large precipitation events and greater relative humidity at Absaraka compared to Dickinson. Weeds were removed from plots during 2015 to allow separation of weed suppression from other possible mulch impacts; therefore, yield data do not reveal striking differences among mulch treatments. Because previous research has demonstrated the impact of weed management during the establishment of strawberries in a matted row system, we concluded that hemp mulch may provide more durable weed suppression compared to paper mulch, which would increase strawberry yield protection in an MRP system. Material cost may be an issue for implementing hemp mulch, as hemp hurd cost was 25 times paper mulch at the application rates used in this study. However, hemp mulch could still be a beneficial option, especially for organic strawberry growers desiring a renewable and environmentally sound replacement for plastic mulch who are able to find affordable local sources of this material.

To tackle the problem of soil erosion and moisture stress, the government of Ethiopia introduced a yearly mass campaign where communities get together and implement various soil and water conservation (SWC) and water harvesting (WH) practices. Although the interventions are believed to have reduced soil erosion/sediment yield and enhanced surface and ground water, quantitative information on the impacts of various options at different scales is scarce. The objective of this study was to assess the impacts different land uses, SWC and WH interventions on water and suspended sediment yield (SSY) at plot and watershed scales in the central highlands of Ethiopia. Standard erosion plot experiments and hydrological stations were used to monitor the daily water and SSY during 2014 to 2017. The results show differences between treatments both at plot and watershed scales. Runoff and soil loss were reduced by an average 27 and 37%, respectively due to SWC practices at the plot level. Overall, SWC practices implemented at the watershed level reduced sediment yield by about 74% (in the year 2014), although the magnitude of sediment reduction due to the SWC interventions reduced over time. At both scales it was observed that as the number of years since SWC measures have been in place increased, their effectiveness declined due to the lack of maintenance. This study also revealed that extrapolating of plot data to watershed scale causes over or under estimation of net erosion.

The sustainability of an agricultural field is largely influenced by crop growth habit and management practices such as tillage. Both strongly interact to shape ecosystem properties such as the fluxes and stocks of carbon and nitrogen. Recently, researchers have worked to develop perennial grain crops in order to enhance key ecosystem processes, such as carbon cycling and nitrogen fixation, with the use of perennial crops rather than traditionally used annual crops. In this study, we aimed to understand how soil disturbance combined with vegetation type [annual monoculture crops vs. perennial monocultures (intermediate wheatgrass (IWG)) vs restored native vegetation (RNV)] influenced the soil carbon and nitrogen dynamics. We collected soil samples at two depths (0–15 cm and 15–30 cm) from each vegetation treatment and incubated the soils in the laboratory for 120 days to determine the efflux of carbon and also analyzed the mineralization of both carbon and nitrogen. The results demonstrated the soils from the IWG had the greatest carbon flux, as well as carbon and nitrogen storage (annual monoculture < RNV < IWG). The differences in carbon flux, carbon and nitrogen storage from the IWG to the annual monoculture were 27, 40, 20%, respectively, while the IWG to the RNV was 11, 20, 10%. Shallow soil samples exhibited greater differences in all C and N comparisons between treatments compared to deeper soil samples. Taken together, our findings indicate that crop vegetation type and soil depth strongly influence carbon and nitrogen dynamics.

There are fewer Certified Organic producers in the Mid-South US (southern half of Missouri, western Kentucky and Tennessee, northern Arkansas and eastern Oklahoma) than in other regions of the country such as the Upper Midwest, West Coast, or Northeastern US. Taus et al. (2013) The Professional Geographer 65, 87–102, posit that these clusters suggest regional characteristics impact adoption of organic agriculture and admit that regional studies lack consensus on the role of factors that drive adoption. This paper seeks to understand if there are regionally distinct challenges and opportunities for organic production in the region. Fourteen certified organic producers in Missouri were interviewed and areas of challenges and opportunities specific to their certification were identified within the three a priori themes of (1) biophysical characteristics, (2) marketing infrastructure and (3) financial feasibility. We suggest directions for future policy support from the National Organic Program (NOP) and bolstered feedback structures within the National Organic Standards Board to address regional disparities.

Although consumers' interest in organic products has increased in recent years, the total demand for these products is still small in most countries. This mismatch between the positive perception of these products and their limited final demand is the so-called intention-behavior gap. The aim of this study is twofold. The first aim is to evaluate the effect of self-reported attitudes toward organic foods in the willingness to pay (WTP) for these products. Second, we analyze the effects of these self-reported attitudes in the final purchasing decision when consumers are asked to evaluate several food attributes simultaneously. The results show that self-reported attitudes toward organic products are useful predictors of higher WTP and can be arranged in different categories (range 15.2–20.1%). However, when a conjoint analysis of different food attributes was conducted, the segment of pro-organic consumers reported that the origin of the product was more important for them than the production system. This opens a new debate about the advisability of promoting the joint use of both labels (organic and origin labels) to engage pro-organic consumers.

In the Mediterranean Basin, sheep meat production systems are based on grazing, and help to conserve biodiversity, mitigate the greenhouse gases emissions and maintain the population in rural areas. However, the lack of differentiation of pastoral systems, as opposed to the intensive model, puts its continuity at risk. In this sense, organic farming can be an alternative to sustain extensive sheep-cereal production systems in marginal Mediterranean drylands. The aim of this research was to evaluate the conversion possibilities of pastoral meat sheep production systems to the organic production model in the Mediterranean Basin, working with the autochthonous Segureña breed sheep. 46 farms were studied, classified into four clusters by mean of multivariate analysis. In order to determine the degree to which farms approached the organic model, 60 variables, grouped into nine indicators were analyzed to obtain an Organic Conversion Index (OCI). The Nutritional management indicator has a high value of approaching the organic model, as well as Animal welfare and Food safety. Marketing and business management, Breeds and reproduction, Weed and pest control and Sustainable pasture management indicators also reach a good approximation level. Only the Breeds and reproduction indicator presented values with significant differences between clusters. The average value of the OCI for the 46 farms ranges from 63 to 70%, and therefore it can be concluded that extensive meat sheep herds in the region are close to this production model. Among the recommendations that can be made to improve the conversion possibilities to the organic model are: (i) to increase own fodder production or find a way to obtain it easily and economically; (ii) to complete the plant−soil−animal cycle, (iii) to seek greater marketing autonomy and (iv) to achieve closer contact with the final consumer. At the same time, government policy both in Spain and other parts of Europe should persevere to find more ways to support the progress of this type of production, in an effort to address limitations and overcome the lack of alternative markets.

Agriculture is one of the high input energy using sectors which ultimately produces the output energy for the survival of human beings. Wheat is an important cereal in the agriculture production system. It is a major food crop and staple food for many countries in the world. Higher population growth has increased demand for wheat, and this demand has been met through the adoption of modern agricultural practices which are heavily dependent on energy. The current study was planned to examine the input energy use efficiency of rainfed wheat growers in Pakistan and Turkey (countries among the top 10 global wheat producers). A total of 119 wheat growers from the rainfed areas of both countries were randomly selected. The data envelopment analysis was executed to estimate the input energy use efficiency score of the growers. The results of the study revealed that almost a similar source of input energy is used in both countries in wheat cultivation. The largest input energy consumption in Turkey was nitrogen fertilizer (10,531.50 MJ ha−1), while in Pakistan was farmyard manure (12,837.32 MJ ha−1). The Turkish growers have higher energy use efficiency 2.42 as compared to Pakistani growers, whose energy use efficiency was 1.09. Results further revealed that there is a substantial potential for energy savings in both countries by optimizing energy use. The study concluded that the exchange of energy-efficient practices between both countries can significantly reduce energy use and improve the yield of wheat.

Double-cropping winter rye cover crops (CC) with soybean in the North Central US could help with the global effort to sustainably intensify agriculture. Studies addressing the management of these systems are limited. Therefore, a field study was conducted from 2017 to 2019 in Central Iowa, US to evaluate winter rye CC biomass production, aboveground N accumulation, estimated economics, estimated within-field energy balance and estimated greenhouse gas (GHG) emissions under three N application rates (0, 60, 120 kg N ha−1) and three planting methods (pre- and post-harvest broadcast and post-harvest drilling). Averaged over N rates, all planting methods resulted in >5.0 Mg ha−1 year−1 rye aboveground biomass dry matter. Averaged over the 2-year study and compared with unfertilized treatments, applying 60 kg N ha−1 produced 1.1 Mg ha−1 more aboveground biomass (6.1 vs 5.0 Mg ha−1), accumulated 30 kg ha−1 more N in aboveground biomass (88 vs 58 kg N ha−1), and led to 20 GJ ha−1 more net energy. Biomass production was not significantly higher with 120 kg N ha−1 compared with the 60 kg N ha−1 rate. Even when accounting for an estimated 0.75 Mg ha−1 of above ground rye biomass left in the field after harvesting, more N was removed than applied at the 60 kg N ha−1 rate. The minimum rye prices over the 2-year study needed for double-cropping winter rye CC to be profitable (breakeven prices) averaged $117 and $104 Mg−1 for the 0 and 60 kg N ha−1 rates, which factors in estimated soybean yield reductions in 2019 compared with local averages but not off-site transportation. GHG emissions were estimated to increase approximately threefold between the unfertilized and 60 kg N ha−1 rates without considering bioenergy offsets. While environmental tradeoffs need further study, results suggest harvesting fertilized rye CC biomass before planting soybean is a promising practice for the North Central US to maximize total crop and net energy production.

Land degradation is a global challenge that affects lives and livelihoods in many communities. Since 1950, about 65% of Africa's cropland, on which millions of people depend, has been affected by land degradation caused by mining, poor farming practices and illegal logging. One-quarter of the land area of Ethiopia is severely degraded. As part of interventions to restore ecosystem services, exclosures have been implemented in Ethiopia since the 1980s. But the lack of tools to support prioritization and more efficient targeting of areas for large-scale exclosure-based interventions remains a challenge. Within that perspective, the overarching objectives of the current study were: (i) to develop a Geographic Information System-based multicriteria decision-support tool that would help in the identification of suitable areas for exclosure initiatives; (ii) to provide spatially explicit information, aggregated by river basin and agroecology, on potential areas for exclosure interventions and (iii) to conduct ex-ante analysis of the potential of exclosure areas for improving ecosystem services in terms of increase in above-ground biomass (AGB) production and carbon storage. The results of this study demonstrated that as much as 10% of Ethiopia's land area is suitable for establishing exclosures. This amounts to 11 million hectares (ha) of land depending on the criteria used to define suitability for exclosure. Of this total, a significant proportion (0.5–0.6 million ha) is currently under agricultural land-use systems. In terms of propriety river basins, we found that the largest amount of suitable area for exclosures falls in the Abay (2.6 million ha) and Tekeze (2.2 million ha) river basins, which are hosts to water infrastructure such as hydropower dams and are threatened by siltation. Ex-ante analysis of ecosystem services indicated that about 418 million tons of carbon can be stored in the AGB through exclosure land use. Ethiopia has voluntarily committed to the Bonn Challenge to restore 15 million ha of degraded land by 2025. The decision-support tool developed by the current study and the information so generated go toward supporting the planning, implementation and monitoring of these kinds of local and regional initiatives.

This study is aimed to evaluate the efficiency of biochar and crude glycerin as additives in N retention throughout the composting of cattle slaughterhouse waste in static piles receiving forced aeration. There were five treatments (control, biochar accounting for 5 and 10%, and glycerin accounting for 5 and 10%, both at total solids) and four times (20, 50, 70 and 90 days of composting). The slaughterhouse waste was composted with a bulking agent at a ratio of 3:1, and the mixtures of waste and the tested additives were placed in nylon bags. The piles reached thermophilic temperatures soon after the process started and following turnings. The reductions of volatile solids, carbon, hemicellulose, cellulose and lignin were not influenced by the additives, resulting in averages of 69.1, 67.1, 62.1, 51.6 and 35.3%, respectively. The control showed greater N losses (58.38%), compared to the treatments with additives. The inclusions of biochar yielded an average loss of 48.47% N, while 10% of glycerin resulted in the lowest N losses (44.83%). The use of biochar and glycerin as additives in the composting of slaughterhouse waste is recommended in order to decrease N losses and improve the concentration of nutrients, without compromising the biodegradation of organic components.