Smart Fertilizers and Innovative Organic Amendments for Sustainable Agricultural Systems

A special issue of Agronomy (ISSN 2073-4395). This special issue belongs to the section "Soil and Plant Nutrition".

Deadline for manuscript submissions: closed (20 January 2021) | Viewed by 62204

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Guest Editor
BIOREN, Universidad de la Frontera, Temuco, Chile
Interests: Soil; Materials Chemistry; Plant Biology; Soil Fertility; Environmental Science; Soil Analysis; Plant Physiology; Biotechnology; Plant Nutrition; Adsorption

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Co-Guest Editor
CNRS, Campus AgroParisTech, Batiment EGER, 78850 Thiverval-Grignon, France
Interests: soil biogeochemistry; soil C sequestration; black carbon; biochar; soil biology; deep soil horizons; organic soil amendments; grassland management
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Co-Guest Editor
Nanobiotechnology Laboratory, Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Biotechnological Bioresource Nucleus, BIOREN UFRO, Universidad de La Frontera, Temuco 4811230, Chile
Interests: Environment; Environmental Science; Biotechnology; Environmental Analysis; Environmental Impact Assessment; Plant Biotechnology; Soil Analysis; Water Treatment; Nanomaterials; Soil Fertility
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Sustainable agricultural practices are needed to provide food security for a growing global population. Food production is usually associated with high nutrient inputs in the form of mineral fertilisers. Since the beginning of agriculure, such practices have led to soil degradation and the release of environmental contaminants. In this Special Issue, we will focus on innovations in organic and inorganic fertiliser production. We welcome studies concerning new approaches for smart fertiliser development, including bioformulations with mineral particles, nanomaterials, and plant growth promoting microorganisms. We especially encourage authors taking advantage of ecological interactions to improve plant nutrient-use efficiency. Moreover, we would like to include contributions that focus on organic amendments to increase or propitiate the terrestrial C sequestration and stabilization, in order to contribute to mitigating climate change at the same time increasing food security by soil fertility, thus making win–win–win scenarios. Such techniques may concern, but are not limited to, innovative organic waste recycling procedures and new applications of mycorrhizae, rhizobioms, or free living soil bacteria and fungi.

Prof. Dr. Maria de la Luz Mora
Dr. Cornelia Rumpel
Dr. Marcela Calabi-Floody
Guest Editors

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Keywords

  • sustainable agriculture
  • ecotechnology
  • carbon sequestration
  • soil fertility
  • waste recycling
  • bioformulations
  • innovation
  • PGPB
  • mycorrhizae

Published Papers (12 papers)

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Editorial

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5 pages, 239 KiB  
Editorial
Closing Biogeochemical Cycles and Meeting Plant Requirements by Smart Fertilizers and Innovative Organic Amendments
by María de la Luz Mora, Marcela Calabi-Floody and Cornelia Rumpel
Agronomy 2021, 11(6), 1158; https://doi.org/10.3390/agronomy11061158 - 05 Jun 2021
Cited by 2 | Viewed by 2294
Abstract
Expansion of farmland with food production as a major service has been largely associated with conversion of natural ecosystems like the Amazon and Savanna into new agricultural land [...] Full article

Research

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14 pages, 1083 KiB  
Article
Biochar-Compost Interactions as Affected by Weathering: Effects on Biological Stability and Plant Growth
by Marie-Liesse Aubertin, Cyril Girardin, Sabine Houot, Cécile Nobile, David Houben, Sarah Bena, Yann Le Brech and Cornelia Rumpel
Agronomy 2021, 11(2), 336; https://doi.org/10.3390/agronomy11020336 - 13 Feb 2021
Cited by 11 | Viewed by 3642
Abstract
Biochar addition to compost is of growing interest as soil amendment. However, little is known about the evolution of material properties of biochar-compost mixtures and their effect on plants after exposure to physical weathering. This study aimed to investigate the physico-chemical characteristics of [...] Read more.
Biochar addition to compost is of growing interest as soil amendment. However, little is known about the evolution of material properties of biochar-compost mixtures and their effect on plants after exposure to physical weathering. This study aimed to investigate the physico-chemical characteristics of fresh and weathered biochar-compost mixtures, their biological stability and their effect on ryegrass growth. To this end, we used the contrasting stable isotope signatures of biochar and compost to follow their behavior in biochar-compost mixtures subjected to artificial weathering during 1-year of incubation. We assessed their impact on ryegrass growth during a 4-week greenhouse pot experiment. Weathering treatment resulted in strong leaching of labile compounds. However, biochar-compost interactions led to reduced mass loss and fixed carbon retention during weathering of mixtures. Moreover, weathering increased carbon mineralization of biochar-compost mixtures, probably due to the protection of labile compounds from compost within biochar structure, as well as leaching of labile biochar compounds inhibiting microbial activity. After soil application, weathered mixtures could have positive effects on biomass production. We conclude that biochar-compost interactions on soil microbial activity and plant growth are evolving after physical weathering depending on biochar production conditions. Full article
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19 pages, 510 KiB  
Article
Innovative Controlled-Release Polyurethane-Coated Urea Could Reduce N Leaching in Tomato Crop in Comparison to Conventional and Stabilized Fertilizers
by Luca Incrocci, Rita Maggini, Tommaso Cei, Giulia Carmassi, Luca Botrini, Ferruccio Filippi, Ronald Clemens, Cristian Terrones and Alberto Pardossi
Agronomy 2020, 10(11), 1827; https://doi.org/10.3390/agronomy10111827 - 20 Nov 2020
Cited by 18 | Viewed by 3091
Abstract
Large amounts of fertilizers are being used in agriculture to sustain growing demands for food, especially in vegetable production systems. Soluble fertilizers can generally ensure high crop yields, but excessive leaching of nutrients, mainly as nitrate, can be a major cause of water [...] Read more.
Large amounts of fertilizers are being used in agriculture to sustain growing demands for food, especially in vegetable production systems. Soluble fertilizers can generally ensure high crop yields, but excessive leaching of nutrients, mainly as nitrate, can be a major cause of water pollution. Controlled-release fertilizers improve the nutrient use efficiency and lower the environmental hazard, usually without affecting the production. In this study, an innovative controlled-release coated urea fertilizer was compared to conventional nitrogen (N) fertilizers and a soluble ammonium-based fertilizer containing a nitrification inhibitor, in a round table tomato cultivation. Both the water and N balance were evaluated for each treatment, along with the yield and quality of the production. The experiment was repeated in three different seasons (spring, autumn and summer-autumn) in a glasshouse to prevent the effect of uncontrolled rainfall. The results indicated that N leaching decreased by increasing the percentage of coated urea. The application of at least 50% total N as coated urea strongly reduced N leaching and improved N agronomic efficiency in comparison with traditional fertilizers, ensuring at the same time a similar fruit production. Due to reduced leaching, the total N amount commonly applied by growers could be lowered by 25% without detrimental effects on commercial production. Full article
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14 pages, 1079 KiB  
Article
Improved Growth and Yield Response of Jew’s Mallow (Corchorus olitorius L.) Plants through Biofertilization under Semi-Arid Climate Conditions in Egypt
by Ahmed Fathy Yousef, Mohamed Ahmed Youssef, Muhammad Moaaz Ali, Muhammed Mustapha Ibrahim, Yong Xu and Rosario Paolo Mauro
Agronomy 2020, 10(11), 1801; https://doi.org/10.3390/agronomy10111801 - 16 Nov 2020
Cited by 10 | Viewed by 2943
Abstract
This study was conducted to comparatively assess the effects of fertilization typology (organic, inorganic, and biofertilization) on the growth, yield, and compositional profile of Jew’s mallow. The experiment was carried out over two growing seasons, under semi-arid climate conditions on silty loam soil. [...] Read more.
This study was conducted to comparatively assess the effects of fertilization typology (organic, inorganic, and biofertilization) on the growth, yield, and compositional profile of Jew’s mallow. The experiment was carried out over two growing seasons, under semi-arid climate conditions on silty loam soil. We adopted three fertilization strategies: (1) inorganic NPK fertilizer (146, 74, and 57 kg ha−1 for N, P2O5, and K2O, respectively), (2) farmyard manure (36 m3 ha−1), and (3) a biofertilizer (a set of mixed cultures of Bacillus spp., Candida spp., and Trichoderma spp. at 36 L ha−1). Treatment combinations were control (without fertilization, T1), NPK fertilizer (T2), farmyard manure (FYM, T3), biofertilizer (T4), NPK+biofertilizer (T5), and FYM+biofertilizer (T6). The T5 treatment maximized both plant and leaf biomass (up to 31.6 and 8.0 t ha−1, respectively), plant height (68.5 cm), leaf area (370 cm m−2), leaf protein content (18.7%), as well as N, P, and K concentration in leaves (2.99, 0.88, and 2.01 mg 100 g−1, respectively). The leaves’ weight incidence was lower in T5 treatment (36.7%) as compared to the unfertilized plants (T1). The results revealed that the combined application of inorganic NPK plus biofertilizer is most beneficial to increase growth, yield, and nutrient accumulation in Jew’s mallow plants. Full article
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12 pages, 1394 KiB  
Communication
Suitability of Black Soldier Fly Frass as Soil Amendment and Implication for Organic Waste Hygienization
by Thomas Klammsteiner, Veysel Turan, Marina Fernández-Delgado Juárez, Simon Oberegger and Heribert Insam
Agronomy 2020, 10(10), 1578; https://doi.org/10.3390/agronomy10101578 - 15 Oct 2020
Cited by 106 | Viewed by 13339
Abstract
Because of its nutritious properties, the black soldier fly has emerged as one of the most popular species in advancing circular economy through the re-valorization of anthropogenic organic wastes to insect biomass. Black soldier fly frass accumulates as a major by-product in artificial [...] Read more.
Because of its nutritious properties, the black soldier fly has emerged as one of the most popular species in advancing circular economy through the re-valorization of anthropogenic organic wastes to insect biomass. Black soldier fly frass accumulates as a major by-product in artificial rearing set-ups and harbors great potential to complement or replace commercial fertilizers. We applied frass from larvae raised on different diets in nitrogen-equivalent amounts as soil amendment, comparing it to NH4NO3 fertilizer as a control. While the soil properties did not reveal any difference between mineral fertilizer and frass, principal component analysis showed significant differences that are mainly attributed to nitrate and dissolved nitrogen contents. We did not find significant differences in the growth of perennial ryegrass between the treatments, indicating that frass serves as a rapidly acting fertilizer comparable to NH4NO3. While the abundance of coliform bacteria increased during frass maturation, after application to the soil, they were outcompeted by gram-negatives. We thus conclude that frass may serve as a valuable fertilizer and does not impair the hygienic properties of soils. Full article
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15 pages, 782 KiB  
Article
Application of Single Superphosphate with Humic Acid Improves the Growth, Yield and Phosphorus Uptake of Wheat (Triticum aestivum L.) in Calcareous Soil
by Muhammad Izhar Shafi, Muhammad Adnan, Shah Fahad, Fazli Wahid, Ahsan Khan, Zhen Yue, Subhan Danish, Muhammad Zafar-ul-Hye, Martin Brtnicky and Rahul Datta
Agronomy 2020, 10(9), 1224; https://doi.org/10.3390/agronomy10091224 - 19 Aug 2020
Cited by 109 | Viewed by 7060
Abstract
In calcareous soil, the significant portion of applied phosphorus (P) fertilizers is adsorbed on the calcite surface and becomes unavailable to plants. Addition of organic amendments with chemical fertilizers can be helpful in releasing the absorbed nutrients from these surfaces. To check out [...] Read more.
In calcareous soil, the significant portion of applied phosphorus (P) fertilizers is adsorbed on the calcite surface and becomes unavailable to plants. Addition of organic amendments with chemical fertilizers can be helpful in releasing the absorbed nutrients from these surfaces. To check out this problem, a field experiment was conducted for two years to determine the effect of P fertilizers and humic acid (HA) in enhancing P availability in soil and their ultimate effect on growth, yield and P uptake of wheat in calcareous soils. The experiment was comprised of five levels of P (0, 45, 67.5, 90 and 112.5 kg P2O5 ha−1) as a single superphosphate (SSP) and 2 levels of locally produced humic acid (with and without HA) arranged in a two factorial randomized complete block design (RCBD) with three replications. Wheat plant height, spike length, number of grains per spike, 1000-grain weight, grain, straw and biological yield were significantly improved by the addition of HA with SSP. Very often, the performance of 67.5 kg P2O5 ha−1 with HA were either similar or better than 90 or even 112.5 kg P2O5 ha−1 applied without HA. Post-harvest soil organic matter, AB-DTPA extractable and water-soluble P, plant P concentration and its uptake were also significantly improved by the addition of HA with SSP compared to sole SSP application. It was evident that P efficiency could be increased with HA addition and it has the potential to improve crop yield and plants P uptake in calcareous soils. Full article
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17 pages, 3528 KiB  
Article
Silicon Modulates the Production and Composition of Phenols in Barley under Aluminum Stress
by Isis Vega, Cornelia Rumpel, Antonieta Ruíz, María de la Luz Mora, Daniel F. Calderini and Paula Cartes
Agronomy 2020, 10(8), 1138; https://doi.org/10.3390/agronomy10081138 - 05 Aug 2020
Cited by 19 | Viewed by 2965
Abstract
Silicon (Si) exerts beneficial effects in mitigating aluminum (Al) toxicity in different plant species. These include attenuating oxidative damage and improving structural strengthening as a result of the increased production of secondary metabolites such as phenols. The aim of this research was to [...] Read more.
Silicon (Si) exerts beneficial effects in mitigating aluminum (Al) toxicity in different plant species. These include attenuating oxidative damage and improving structural strengthening as a result of the increased production of secondary metabolites such as phenols. The aim of this research was to evaluate the effect of Si on phenol production and composition in two barley cultivars under Al stress. Our conceptual approach included a hydroponic experiment with an Al-tolerant (Sebastian) and an Al-sensitive (Scarlett) barley cultivar treated with two Al doses (0 or 0.2 mM of Al) and two Si doses (0 or 2 mM) for 21 days. Chemical, biochemical and growth parameters were assayed after harvest. Our results indicated that the Al and Si concentration decreased in both cultivars when Al and Si were added in combination. Silicon increased the antioxidant activity and soluble phenol concentration, but reduced lipid peroxidation irrespective of the Al dose. Both barley cultivars showed changes in culm creep rate, flavonoids and flavones concentration, lignin accumulation and altered lignin composition in Si and Al treatments. We concluded that Si fertilization could increase the resistance of barley to Al toxicity by regulating the metabolism of phenolic compounds with antioxidant and structural functions. Full article
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12 pages, 1109 KiB  
Article
Cover Crop Selection by Jointly Optimizing Biomass Productivity, Biological Nitrogen Fixation, and Transpiration Efficiency: Application to Two Crotalaria Species
by Verónica Berriel, Jorge Monza and Carlos H. Perdomo
Agronomy 2020, 10(8), 1116; https://doi.org/10.3390/agronomy10081116 - 01 Aug 2020
Cited by 10 | Viewed by 2679
Abstract
Crotalaria spectabilis and Crotalaria juncea are cover crops (CC) that are used in many different regions. Among the main attributes of these species are their high potential for biomass production and biological fixation of nitrogen (BNF). Attempting to maximize these attributes, while minimizing [...] Read more.
Crotalaria spectabilis and Crotalaria juncea are cover crops (CC) that are used in many different regions. Among the main attributes of these species are their high potential for biomass production and biological fixation of nitrogen (BNF). Attempting to maximize these attributes, while minimizing water consumption through high transpiration efficiency (TE), is a challenge in the design of sustainable agricultural rotations. In this study, the relationship between biomass productivity, BNF, and TE in C. spectabilis and C. juncea was evaluated. For this purpose, an experiment was carried out under controlled conditions without water limitations and using non-inoculated soil. BNF was determined by the natural abundance of 15N, while TE was estimated by several different methods, such as gravimetric or isotopic method (13C). C. juncea produced 42% less dry matter, fixed 28% less nitrogen from the air, and had 20% less TE than C. spectabilis. TE results in both species were consistent across methodologies. Under simulated environmental conditions of high temperature and non-limiting soil water content, C. spectabilis was a relatively more promising species than C. juncea to be used as CC. Full article
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19 pages, 21606 KiB  
Article
Improving Productivity in Integrated Fish-Vegetable Farming Systems with Recycled Fish Pond Sediments
by Chau Thi Da, Phan Anh Tu, John Livsey, Van Tai Tang, Håkan Berg and Stefano Manzoni
Agronomy 2020, 10(7), 1025; https://doi.org/10.3390/agronomy10071025 - 16 Jul 2020
Cited by 7 | Viewed by 5066
Abstract
The increasing intensification of aquaculture systems requires the development of strategies to reduce their environmental impacts such as pollution caused by the discharge of nutrient rich sediments into local water bodies. Recycling of fish pond sediments (FPS) as fertilizer has been proposed as [...] Read more.
The increasing intensification of aquaculture systems requires the development of strategies to reduce their environmental impacts such as pollution caused by the discharge of nutrient rich sediments into local water bodies. Recycling of fish pond sediments (FPS) as fertilizer has been proposed as a possible solution that may also reduce the reliance on synthetic fertilizers. With a case study in the Mekong Delta, Vietnam, we determined suitable mixtures of striped catfish (Pangasianodon hypophthalmus) pond sediment (PPS) and locally sourced organic amendments of rice straw (RS), or common water hyacinth (WH) to fertilize cucumber plants (Cucumis sativus L.) in an integrated cucumber–giant gourami fish (Osphronemus goramy) farming system. Highest nutrient concentrations were found when mixing 30% PPS with 70% RS or WH. When used in combination with chemical fertilizer, it was found that a 25% to 75% reduction in chemical fertilizer application could be achieved, while also increasing cucumber yields, with the highest yields found when RS was used in organic amendments. In combination with the additional income from fish production, integrated farming systems such as that demonstrated in this study, may increase both farm income and production diversity. Full article
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27 pages, 4269 KiB  
Article
Solubility and Efficiency of Rock Phosphate Fertilizers Partially Acidulated with Zeolite and Pillared Clay as Additives
by Ana Paula Bettoni Teles, Marcos Rodrigues and Paulo Sergio Pavinato
Agronomy 2020, 10(7), 918; https://doi.org/10.3390/agronomy10070918 - 27 Jun 2020
Cited by 14 | Viewed by 7232
Abstract
Soluble phosphates are the most common sources currently used in crop production in tropical soils; however, they present low efficiency and are more expensive than natural rock phosphates. The objective was to develop new phosphate fertilizers with slow solubility through the partial acidification [...] Read more.
Soluble phosphates are the most common sources currently used in crop production in tropical soils; however, they present low efficiency and are more expensive than natural rock phosphates. The objective was to develop new phosphate fertilizers with slow solubility through the partial acidification of rock phosphates (RPs), incorporating materials with adsorption characteristics to favor slow dissolution and prevent phosphorus (P) fixation in the soil. Three rock phosphates, Araxá (ARP), Bayovar (BRP) and Morocco (MRP), were evaluated at two acidulation levels (25 and 50% Ac.) and two additives; pillared clays (PILC) and zeolites (Zeo), plus triple superphosphate (TSP) and a control (nil-P). The soil diffusion was evaluated in concentric rings in Petri dishes. Solubility was evaluated in leaching columns and sampled in layers from surface for P forms in the soil profile. The relative agronomic efficiency (RAE) was evaluated in maize. Greater diffusion was provided by TSP, followed by BRP and MRP both with 50% Ac. + Zeo, and MRP with 50% Ac. + PILC. Percolated P was more pronounced under TSP, followed by RPs (BRP and MRP) with 50% Ac. + Zeo. BRP and MRP + 50% Ac. were the most promising sources with RAE above 74% compared to TSP. Full article
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10 pages, 2468 KiB  
Article
Assessing the Potential of Jellyfish as an Organic Soil Amendment to Enhance Seed Germination and Seedling Establishment in Sand Dune Restoration
by Iraj Emadodin, Thorsten Reinsch, Raffaele-Romeo Ockens and Friedhelm Taube
Agronomy 2020, 10(6), 863; https://doi.org/10.3390/agronomy10060863 - 18 Jun 2020
Cited by 3 | Viewed by 2214
Abstract
Worldwide, sandy coastlines are affected by extensive wind and water erosion. Both soil quality and periodic drought present major problems for sand dune restoration projects. Hence, soil amendments are needed to improve soil quality and enhance soil restoration efficiency. The jellyfish population has [...] Read more.
Worldwide, sandy coastlines are affected by extensive wind and water erosion. Both soil quality and periodic drought present major problems for sand dune restoration projects. Hence, soil amendments are needed to improve soil quality and enhance soil restoration efficiency. The jellyfish population has increased in some aquatic ecosystems and is often considered as a nuisance because of their negative impacts on marine ecosystem productivity as well as coastal attractiveness. Thus, development of new products derived from jellyfish biomass has received attention from researchers although utilization is still at a preliminary stage. Herein, our main objective was to test seed germination, seedling establishment, and seedling vitality of annual ryegrass (Lolium multiflorum L.) when supplied with organic soil amendment from two different jellyfish species (Aurelia aurita and Cyanea capillata) in comparison with an unfertilized control and mineral fertilizer treatment. We hypothesized that jellyfish dry matter as an organic soil amendment would improve seed germination and seedling establishment in sand dune environments. Germination and seedling growth experiments were conducted in the laboratory and greenhouse. The results indicate that jellyfish enhanced seedling growth and establishment in sand dune soil significantly (p < 0.05 and p < 0.01) under water scarcity conditions. Therefore, jellyfish may have potential for an auxiliary role in sand dune restoration projects in coastal areas in the future. Full article
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8 pages, 1299 KiB  
Communication
Earthworms (Lumbricus terrestris L.) Mediate the Fertilizing Effect of Frass
by Anne-Maïmiti Dulaurent, Guillaume Daoulas, Michel-Pierre Faucon and David Houben
Agronomy 2020, 10(6), 783; https://doi.org/10.3390/agronomy10060783 - 31 May 2020
Cited by 13 | Viewed by 7321
Abstract
With the forecasted dramatic growth of insect rearing in the near future, frass (insect excreta) has been increasingly considered a sustainable resource for managing plant nutrition in cropping systems and a promising alternative to conventional fertilizer. However, the impact of soil fauna on [...] Read more.
With the forecasted dramatic growth of insect rearing in the near future, frass (insect excreta) has been increasingly considered a sustainable resource for managing plant nutrition in cropping systems and a promising alternative to conventional fertilizer. However, the impact of soil fauna on its fertilizing effect has not been investigated so far. In this study, we investigated the effect of earthworms (Lumbricus terrestris L.) on nitrogen (N), phosphorus (P), potassium (K) and calcium (Ca) uptake and crop growth in the presence of frass from mealworm (Tenebrio molitor L.). Using a pot experiment, we found that earthworms increased N, P, K and Ca concentration in barley (Hordeum vulgare L.) in the presence of frass, suggesting that earthworm activity enhances the short-term recycling of nutrients from frass. Compared to treatments with and without frass and earthworms, the specific leaf area of barley was the highest in the presence of both earthworms and frass. This confirms that earthworms and frass have a synergistic effect on soil fertility. Overall, our study shows that earthworms may improve the efficiency of organic fertilizers and argues therefore for the importance of developing sustainable agricultural practices that promote earthworm populations. Full article
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