RESUMO
Sustainability of agricultural production and mitigation of global warming rely on the regeneration of soil organic carbon (SOC), in particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) forms. We conducted a global systematic meta-analysis of the effects of regenerative management practices on SOC, POC, and MAOC in cropland, finding: 1) no-till (NT) and cropping system intensification increase SOC (11.3% and 12.4%, respectively), MAOC (8.5% and 7.1%, respectively), and POC (19.7% and 33.3%, respectively) in topsoil (0 to 20 cm), but not in subsoil (>20 cm); 2) experimental duration, tillage frequency, the intensification type, and rotation diversity moderate the effects of regenerative management; and 3) NT synergized with integrated crop-livestock (ICL) systems to greatly increase POC (38.1%) and cropping intensification synergized with ICL systems to greatly increase MAOC (33.1 to 53.6%). This analysis shows that regenerative agriculture is a key strategy to reduce the soil C deficit inherent to agriculture to promote both soil health and long-term C stabilization.
RESUMO
The larval stages of click beetle (Coleoptera: Elateridae) species, several of which are serious agricultural pests, are called wireworms. Their cryptic subterranean habitat, resilience, among-species differences in ecology and biology, and broad host range, as well as the lack of objective economic injury thresholds, have rendered wireworms a challenging pest complex to control. Significant progress has been made in recent years, introducing a new effective class of insecticides and improving species identification and our understanding of species-specific phenology, chemical ecology (i.e., adult sex pheromones and larval olfactory cues), and abiotic and biotic factors influencing the efficacy of biological control agents. These new developments have created opportunities for further research into improving our risk assessment, monitoring, and integrated pest management capabilities.
Assuntos
Besouros , Inseticidas , Animais , Larva , Ecossistema , AgriculturaRESUMO
BACKGROUND: The soil biota consists of a complex assembly of microbial communities and other organisms that vary significantly across farming systems, impacting soil health and plant productivity. Despite its importance, there has been limited exploration of how different cropping systems influence soil and plant root microbiomes. In this study, we investigated soil physicochemical properties, along with soil and maize-root microbiomes, in an agroecological cereal-legume companion cropping system known as push-pull technology (PPT). This system has been used in agriculture for over two decades for insect-pest management, soil health improvement, and weed control in sub-Saharan Africa. We compared the results with those obtained from maize-monoculture (Mono) cropping system. RESULTS: The PPT cropping system changed the composition and diversity of soil and maize-root microbial communities, and led to notable improvements in soil physicochemical characteristics compared to that of the Mono cropping system. Distinct bacterial and fungal genera played a crucial role in influencing the variation in microbial diversity within these cropping systems. The relative abundance of fungal genera Trichoderma, Mortierella, and Bionectria and bacterial genera Streptomyces, RB41, and Nitrospira were more enriched in PPT. These microbial communities are associated with essential ecosystem services such as plant protection, decomposition, carbon utilization, bioinsecticides production, nitrogen fixation, nematode suppression, phytohormone production, and bioremediation. Conversely, pathogenic associated bacterial genus including Bryobacter were more enriched in Mono-root. Additionally, the Mono system exhibited a high relative abundance of fungal genera such as Gibberella, Neocosmospora, and Aspergillus, which are linked to plant diseases and food contamination. Significant differences were observed in the relative abundance of the inferred metabiome functional protein pathways including syringate degradation, L-methionine biosynthesis I, and inosine 5'-phosphate degradation. CONCLUSION: Push-pull cropping system positively influences soil and maize-root microbiomes and enhances soil physicochemical properties. This highlights its potential for agricultural and environmental sustainability. These findings contribute to our understanding of the diverse ecosystem services offered by this cropping system where it is practiced regarding the system's resilience and functional redundancy. Future research should focus on whether PPT affects the soil and maize-root microbial communities through the release of plant metabolites from the intercrop root exudates or through the alteration of the soil's nutritional status, which affects microbial enzymatic activities.
Assuntos
Microbiota , Resiliência Psicológica , Solo/química , Zea mays , Fungos/genética , Agricultura/métodos , Bactérias/genética , Microbiologia do SoloRESUMO
Micro/nanoplastic (MNP) pollution in soil ecosystems has become a growing environmental concern globally. However, the comprehensive impacts of MNPs on soil health have not yet been explored. We conducted a hierarchical meta-analysis of over 5000 observations from 228 articles to assess the broad impacts of MNPs on soil health parameters (represented by 20 indicators relevant to crop growth, animal health, greenhouse gas emissions, microbial diversity, and pollutant transfer) and whether the impacts depended on MNP properties. We found that MNP exposure significantly inhibited crop biomass and germination, and reduced earthworm growth and survival rate. Under MNP exposure, the emissions of soil greenhouse gases (CO2, N2O, and CH4) were significantly increased. MNP exposure caused a decrease in soil bacteria diversity. Importantly, the magnitude of impact of the soil-based parameters was dependent on MNP dose and size; however, there is no significant difference in MNP type (biodegradable and conventional MNPs). Moreover, MNPs significantly reduced As uptake by plants, but promoted plant Cd accumulation. Using an analytical hierarchy process, we quantified the negative impacts of MNP exposure on soil health as a mean value of -10.2% (-17.5% to -2.57%). Overall, this analysis provides new insights for assessing potential risks of MNP pollution to soil ecosystem functions.
Assuntos
Oligoquetos , Microbiologia do Solo , Poluentes do Solo , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Poluentes do Solo/efeitos adversos , Animais , Solo/química , Microplásticos/análise , Microplásticos/toxicidade , Gases de Efeito Estufa/análise , Nanopartículas/análise , Produtos Agrícolas/crescimento & desenvolvimentoRESUMO
Our current planetary crisis, including multiple jointly acting factors of global change, moves the need for effective ecosystem restoration center stage and compels us to explore unusual options. We here propose exploring combinatorial approaches to restoration practices: management practices are drawn at random and combined from a locally relevant pool of possible management interventions, thus creating an experimental gradient in the number of interventions. This will move the current degree of interventions to higher dimensionality, opening new opportunities for unlocking unknown synergistic effects. Thus, the high dimensionality of global change (multiple jointly acting factors) would be more effectively countered by similar high-dimensionality in solutions. In this concept, regional restoration hubs play an important role as guardians of locally relevant information and sites of experimental exploration. Data collected from such studies could feed into a global database, which could be used to learn about general principles of combined restoration practices, helping to refine future experiments. Such combinatorial approaches to exploring restoration intervention options may be our best hope yet to achieve decisive progress in ecological restoration at the timescale needed to mitigate and reverse the most severe losses caused by global environmental change.
Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Recuperação e Remediação Ambiental/métodos , Ecologia/métodos , Mudança ClimáticaRESUMO
Mountain agroecosystems in Latin America provide multiple ecosystem functions (EFs) and products from global to local scales, particularly for the rural communities who depend on them. Agroforestry has been proposed as a climate-smart farming strategy throughout much of the region to help conserve biodiversity and enhance multiple EFs, especially in mountainous regions. However, large-scale synthesis on the potential of agroforestry across Latin America is lacking. To understand the potential impacts of agroforestry at the continental level, we conducted a meta-analysis examining the effects of agroforestry on biological activity and diversity (BIAD) and multiple EFs across mountain agroecosystems of Latin America. A total of 78 studies were selected based on a formalized literature search in the Web of Science. We analysed differences between (i) silvoarable systems versus cropland, (ii) silvopastoral systems versus pastureland, and (iii) agroforestry versus forest systems, based on response ratios. Response ratios were further used to understand how climate type, precipitation and soil properties (texture) influence key EFs (carbon sequestration, nutrient provision, erosion control, yield production) and BIAD in agroforestry systems. Results revealed that BIAD and EFs related to carbon sequestration and nutrient provisioning were generally higher in agroforestry systems (silvopastoral and silvoarable) compared to croplands and pasturelands without trees. However, the impacts of agroforestry systems on crop yields varied depending on the system considered (i.e., coffee vs. cereals), while forest systems generally provided greater levels of BIAD and EFs than agroforestry systems. Further analysis demonstrated that the impacts of agroforestry systems on BIAD and EFs depend greatly on climate type, soil, and precipitation. For example, silvoarable systems appear to generate the greatest benefits in arid or tropical climates, on sandier soils, and under lower precipitation regimes. Overall, our findings highlight the widespread potential of agroforestry systems to BIAD and multiple EFs across montane regions of Latin America.
Assuntos
Ecossistema , Solo , América Latina , Agricultura/métodos , BiodiversidadeRESUMO
Tropospheric ozone (O3 ) threatens agroecosystems, yet its long-term effects on intricate plant-microbe-soil interactions remain overlooked. This study employed two soybean genotypes of contrasting O3 -sensitivity grown in field plots exposed elevated O3 (eO3 ) and evaluated cause-effect relationships with their associated soil microbiomes and soil quality. Results revealed long-term eO3 effects on belowground soil microbiomes and soil health surpass damage visible on plants. Elevated O3 significantly disrupted belowground bacteria-fungi interactions, reduced fungal diversity, and altered fungal community assembly by impacting soybean physiological properties. Particularly, eO3 impacts on plant performance were significantly associated with arbuscular mycorrhizal fungi, undermining their contribution to plants, whereas eO3 increased fungal saprotroph proliferation, accelerating soil organic matter decomposition and soil carbon pool depletion. Free-living diazotrophs exhibited remarkable acclimation under eO3 , improving plant performance by enhancing nitrogen fixation. However, overarching detrimental consequences of eO3 negated this benefit. Overall, this study demonstrated long-term eO3 profoundly governed negative impacts on plant-soil-microbiota interactions, pointing to a potential crisis for agroecosystems. These findings highlight urgent needs to develop adaptive strategies to navigate future eO3 scenarios.
Assuntos
Microbiota , Micorrizas , Ozônio , Solo/química , Ozônio/efeitos adversos , Ozônio/análise , Microbiologia do Solo , Glycine maxRESUMO
Redesigning agrosystems to include more ecological regulations can help feed a growing human population, preserve soils for future productivity, limit dependency on synthetic fertilizers, and reduce agriculture contribution to global changes such as eutrophication and warming. However, guidelines for redesigning cropping systems from natural systems to make them more sustainable remain limited. Synthetizing the knowledge on biogeochemical cycles in natural ecosystems, we outline four ecological systems that synchronize the supply of soluble nutrients by soil biota with the fluctuating nutrient demand of plants. This synchrony limits deficiencies and excesses of soluble nutrients, which usually penalize both production and regulating services of agrosystems such as nutrient retention and soil carbon storage. In the ecological systems outlined, synchrony emerges from plant-soil and plant-plant interactions, eco-physiological processes, soil physicochemical processes, and the dynamics of various nutrient reservoirs, including soil organic matter, soil minerals, atmosphere, and a common market. We discuss the relative importance of these ecological systems in regulating nutrient cycles depending on the pedoclimatic context and on the functional diversity of plants and microbes. We offer ideas about how these systems could be stimulated within agrosystems to improve their sustainability. A review of the latest advances in agronomy shows that some of the practices suggested to promote synchrony (e.g., reduced tillage, rotation with perennial plant cover, crop diversification) have already been tested and shown to be effective in reducing nutrient losses, fertilizer use, and N2 O emissions and/or improving biomass production and soil carbon storage. Our framework also highlights new management strategies and defines the conditions for the success of these nature-based practices allowing for site-specific modifications. This new synthetized knowledge should help practitioners to improve the long-term productivity of agrosystems while reducing the negative impact of agriculture on the environment and the climate.
Assuntos
Ecossistema , Solo , Humanos , Agricultura , Plantas , CarbonoRESUMO
The effects of compost on physical and chemical characteristics of soil are well-studied but impacts on soil microbiomes are poorly understood. This research tested effects of green waste compost on bacterial communities in soil infested with the plant pathogen Fusarium oxysporum. Compost was added to pathogen-infested soil and maintained in mesocosms in a greenhouse experiment and replicated growth chamber experiments. Bacteria and F. oxysporum abundance were quantified using quantitative PCR. Taxonomic and functional characteristics of bacterial communities were measured using shotgun metagenome sequencing. Compost significantly increased bacterial abundance 8 weeks after amendment in one experiment. Compost increased concentrations of chemical characteristics of soil, including phosphorus, potassium, organic matter, and pH. In all experiments, compost significantly reduced abundance of F. oxysporum and altered the taxonomic composition of soil bacterial communities. Sixteen bacterial genera were significantly increased from compost in every experiment, potentially playing a role in pathogen suppression. In all experiments, there was a consistent negative effect of compost on functions related to carbohydrate use and a positive effect on bacteria with flagella. Results from this work demonstrate that compost can reduce the abundance of soilborne plant pathogens and raise questions about the role of microbes in plant pathogen suppression.
Assuntos
Compostagem , Fusarium , Solo/química , Microbiologia do Solo , Bactérias/genética , Análise de SequênciaRESUMO
Chemical soil fumigation (CSF) and reductive soil disinfestation (RSD) have been proven to be effective agricultural strategies to improve soil quality, restructure microbial communities, and promote plant growth in soil degradation remediation. However, it is still unclear how RSD and CSF ensure soil and plant health by altering fungal communities. Field experiments were conducted to investigate the effects of CSF with chloropicrin, and RSD with animal feces on soil properties, fungal communities and functional composition, and plant physiological characteristics were evaluated. Results showed that RSD and CSF treatment improved soil properties, restructured fungal community composition and structure, enhanced fungal interactions and functions, and facilitated plant growth. There was a significant increase in OM, AN, and AP contents in the soil with both CSF and RSD treatments compared to CK. Meanwhile, compared with CK and CSF, RSD treatment significantly increased biocontrol Chaetomium relative abundance while reducing pathogenic Neonectria relative abundance, indicating that RSD has strong inhibition potential. Furthermore, the microbial network of RSD treatment was more complex and interconnected, and the functions of plant pathogens, and animal pathogen were decreased. Importantly, RSD treatment significantly increased plant SOD, CAT, POD activity, SP, Ca, Zn content, and decreased MDA, ABA, Mg, K, and Fe content. In summary, RSD treatment is more effective than CSF treatment, by stimulating the proliferation of probiotic communities to further enhance soil health and plant disease resistance.
Assuntos
Microbiota , Micobioma , Panax , Solo/química , Agricultura/métodos , Microbiologia do SoloRESUMO
Microplastics threaten soil ecosystems, strongly influencing carbon (C) and nitrogen (N) contents. Interactions between microplastic properties and climatic and edaphic factors are poorly understood. We conducted a meta-analysis to assess the interactive effects of microplastic properties (type, shape, size, and content), native soil properties (texture, pH, and dissolved organic carbon (DOC)) and climatic factors (precipitation and temperature) on C and N contents in soil. We found that low-density polyethylene reduced total nitrogen (TN) content, whereas biodegradable polylactic acid led to a decrease in soil organic carbon (SOC). Microplastic fragments especially depleted TN, reducing aggregate stability, increasing N-mineralization and leaching, and consequently increasing the soil C/N ratio. Microplastic size affected outcomes; those <200 µm reduced both TN and SOC contents. Mineralization-induced nutrient losses were greatest at microplastic contents between 1 and 2.5% of soil weight. Sandy soils suffered the highest microplastic contamination-induced nutrient depletion. Alkaline soils showed the greatest SOC depletion, suggesting high SOC degradability. In low-DOC soils, microplastic contamination caused 2-fold greater TN depletion than in soils with high DOC. Sites with high precipitation and temperature had greatest decrease in TN and SOC contents. In conclusion, there are complex interactions determining microplastic impacts on soil health. Microplastic contamination always risks soil C and N depletion, but the severity depends on microplastic characteristics, native soil properties, and climatic conditions, with potential exacerbation by greenhouse emission-induced climate change.
Assuntos
Carbono , Clima , Microplásticos , Nitrogênio , Solo , Nitrogênio/análise , Solo/química , Carbono/análise , Poluentes do Solo/análiseRESUMO
The aim of this study is to investigate the effects of vermicompost on the biological and microbial properties of lettuce rhizosphere in an agricultural field in Samsun, Turkey. The experiment was conducted in a completely randomised design (CRD) and included four vermicompost dosages (0%, 1%, 2%, and 4%) and two application methods (with and without plants). Batavia lettuce was selected as the test plant due to its sensitivity to environmental conditions and nutrient deficiencies. The study evaluated the changes in organic matter (OM), pH, electrical conductivity (EC), carbon dioxide (CO2), dehydrogenase activity (DHA), microbial biomass carbon (MBC), and catalase activity (CA) in the rhizosphere of lettuce plants treated with different vermicompost levels (0%, 1%, 2%, and 4%). The findings showed that vermicompost application significantly increased chlorophyll content in lettuce plants, with the highest content observed in plants treated with V1 compared to the control. Different vermicompost concentrations also influenced chlorophyll b and total chlorophyll levels, with positive effects observed at lower concentrations than the control. Plant height and fresh weight were highest in plants treated with V2, indicating the positive impact of vermicompost on plant growth. Additionally, vermicompost application increased plant dry weight and improved soil properties such as pH, organic matter content, and microbial activity. The findings showed that vermicompost increased the rhizosphere's microbial biomass and metabolic activity, which can be beneficial for plant growth and disease suppression. The study highlights the importance of understanding the effects of organic amendments on soil properties and the microbial community in the rhizosphere, which can contribute to sustainable agricultural practices. Overall, the results suggest that vermicompost can be used as an effective organic amendment for enhancing plant growth and improving soil properties in agricultural fields. Moreover, based on the data, it can be suggested that a dose between 1% and 2% vermicompost is beneficial for the overall growth of plants.
Assuntos
Rizosfera , Solo , Solo/química , Lactuca , Agricultura , Plantas , ClorofilaRESUMO
Even though researches have shown that biochar can improve soil-health and plant-growth even in harsh environments and get rid of harmful heavy metals and new contaminants, it is still not sustainable, affordable, or effective enough. Therefore, scientists are required to develop nanomaterials in order to preserve numerous aquatic and terrestrial species. The carbonaceous chemical known as nano-biochar (N-BC) can be used to get rid of metal contamination and emerging contaminants. However, techniques to reduce hetero-aggregation and agglomeration of nano-biochar are needed that lead to the emergence of emerging nano-biochar (EN-BC) in order to maximise its capacity for adsorption of nano-biochar. To address concerns in regards to the expanding human population and sustain a healthy community, it is imperative to address the problems associated with toxic heavy metals, emerging contaminants, and other abiotic stressors that are threatening agricultural development. Nano-biochar can provide an effective solution for removal of emerging contaminants, toxic heavy metals, and non-degradable substance. This review provides the detailed functional mechanistic and kinetics of nano-biochar, its effectiveness in promoting plant growth, and soil health under abiotic stress. Nonetheless, this review paper has comprehensively illustrated various adsorption study models that will be employed in future research.
Assuntos
Carvão Vegetal , Metais Pesados , Desenvolvimento Vegetal , Poluentes do Solo , Metais Pesados/análise , Carvão Vegetal/química , Poluentes do Solo/análise , Poluentes do Solo/química , Adsorção , Desenvolvimento Vegetal/efeitos dos fármacos , Cinética , Recuperação e Remediação Ambiental/métodosRESUMO
Rise in climate change-induced drought occurrences have amplified pollution of metal(loid)s, deteriorated soil quality, and deterred growth of crops. Rice straw-derived biochars (RSB) and cow manure-enriched biochars (CEB) were used in the investigation (at doses of 0%, 2.5%, 5%, and 7.5%) to ameliorate the negative impacts of drought, improve soil fertility, minimize arsenic pollution, replace agro-chemical application, and maximize crop yields. Even in soils exposed to severe droughts, 3 months of RSB and CEB amendment (at 7.5% dose) revealed decreased bulk density (13.7% and 8.9%), and increased cation exchange capacity (6.0% and 6.3%), anion exchange capacity (56.3% and 28.0%), porosity (12.3% and 7.9%), water holding capacity (37.5% and 12.5%), soil respiration (17.8% and 21.8%), and nutrient contents (especially N and P). Additionally, RSB and CEB decreased mobile (30.3% and 35.7%), bio-available (54.7% and 45.3%), and leachable (55.0% and 56.5%) fractions of arsenic. Further, pot experiments with Bengal gram and coriander plants showed enhanced growth (62-188% biomass and 90-277% length) and reduced arsenic accumulation (49-54%) in above ground parts of the plants. Therefore, biochar application was found to improve physico-chemical properties of soil, minimize arsenic contamination, and augment crop growth even in drought-stressed soils. The investigation suggests utilisation of cow manure for eco-friendly fabrication of nutrient-rich CEB, which could eventually promote sustainable agriculture and circular economy. With the increasing need for sustainable agricultural practices, the use of biochar could provide a long-term solution to enhance soil quality, mitigate the effects of climate change, and ensure food security for future generations. Future research should focus on optimizing biochar application across various soil types and climatic conditions, as well as assessing its long-term effectiveness.
RESUMO
Microplastic pollution has emerged as a critical global environmental issue due to its widespread distribution, persistence, and potential adverse effects on ecosystems and human health. Although research on microplastic pollution in aquatic environments has gained significant attention. However, a limited literature has summarized the impacts of microplastic pollution the agricultural land and human health. Therefore, In the current review, we have discussed how microplastic(s) affect the microorganisms by ingesting the microplastic present in the soil, alternatively affecting the belowground biotic and abiotic components, which further elucidates the negative effects on the above-ground properties of the crops. In addition, the consumption of these crops in the food chain revealed a potential risk to human health throughout the food chain. Moreover, microplastic pollution has the potential to induce a negative impact on agricultural production and food security by altering the physiochemical properties of the soil, microbial population, nutrient cycling, and plant growth and development. Therefore, we discussed in detail the potential hazards caused by microplastic contamination in the soil and through the consumption of food and water by humans in daily intake. Furthermore, further study is urgently required to comprehend how microplastic pollution negatively affects terrestrial ecosystems, particularly agroecosystems which drastically reduces the productivity of the crops. Our review highlights the urgent need for greater awareness, policy interventions, and technological solutions to address the emerging threat of microplastic pollution in soil and plant systems and mitigation strategies to overcome its potential impacts on human health. Based on existing studies, we have pointed out the research gaps and proposed different directions for future research.
Assuntos
Metais Pesados , Microplásticos , Humanos , Microplásticos/toxicidade , Solo/química , Plásticos , Ecossistema , Metais Pesados/toxicidade , Produtos AgrícolasRESUMO
Plants remove carbon dioxide from the atmosphere through photosynthesis. Because agriculture's productivity is based on this process, a combination of technologies to reduce emissions and enhance soil carbon storage can allow this sector to achieve net negative emissions while maintaining high productivity. Unfortunately, current row-crop agricultural practice generates about 5% of greenhouse gas emissions in the United States and European Union. To reduce these emissions, significant effort has been focused on changing farm management practices to maximize soil carbon. In contrast, the potential to reduce emissions has largely been neglected. Through a combination of innovations in digital agriculture, crop and microbial genetics, and electrification, we estimate that a 71% (1,744 kg CO2e/ha) reduction in greenhouse gas emissions from row crop agriculture is possible within the next 15 y. Importantly, emission reduction can lower the barrier to broad adoption by proceeding through multiple stages with meaningful improvements that gradually facilitate the transition to net negative practices. Emerging voluntary and regulatory ecosystems services markets will incentivize progress along this transition pathway and guide public and private investments toward technology development. In the difficult quest for net negative emissions, all tools, including emission reduction and soil carbon storage, must be developed to allow agriculture to maintain its critical societal function of provisioning society while, at the same time, generating environmental benefits.
Assuntos
Agricultura/métodos , Dióxido de Carbono/análise , Conservação dos Recursos Naturais , Produção Agrícola , Tecnologia , Amônia/metabolismo , Produtos Agrícolas/genéticaRESUMO
Conventional petroleum-derived polymers are valued for their versatility and are widely used, owing to their characteristics such as cost-effectiveness, diverse physical and chemical qualities, lower molecular weight, and easy processability for large-scale production. However, the extensive accumulation of such plastics leads to serious environmental issues. To combat this existing situation, an alternative lies in the production of bioplastics from natural and renewable sources such as plants, animals, microbes, etc. Bioplastics obtained from renewable sources are compostable and susceptible to degradation caused by microbes hydrolyzing to CO2, CH4, and biomass. Also, certain additives are reinforced into the bioplastic films to improve their physicochemical properties and degradation rate. However, on degradation, the bio-microplastic (BM) produced could have positive as well as negative impact on the soil health. This article thus focuses on the degradation of various fossil based as well as bio based biodegradable plastics such as polyhydroxyalkanoates (PHA), polyhydroxy butyrate (PHB), polylactic acid (PLA), polybutylene succinate (PBS), polycaprolactone (PCL), and polysaccharide derived bioplastics by mechanical, thermal, photodegradation and microbial approaches. The degradation mechanism of each approach has been discussed in detailed for different bioplastics. How the incorporation or reinforcement of various additives in the biodegradable plastics effects their degradation rates has also been discussed. In addition to that, the impact of generated bio-microplastic on physicochemical properties of soil such as pH, bulk density, carbon, nitrogen content etc. and biological properties such as on genome of native soil microbes and on plant nutritional health have been discussed in detailed.
RESUMO
Soil health plays a crucial role in crop production, both in terms of quality and quantity, highlighting the importance of effective methods for preserving soil quality to ensure global food security. Soil quality indices (SQIs) have been widely utilized as comprehensive measures of soil function by integrating multiple physical, chemical, and biological soil properties. Traditional SQI analysis involves laborious and costly laboratory analyses, which limits its practicality. To overcome this limitation, our study explores the use of visible near-infrared (vis-NIR) spectroscopy as a rapid and non-destructive alternative for predicting soil properties and SQIs. This study specifically focused on seven soil indicators that contribute to soil fertility, including pH, organic matter (OM), potassium (K), calcium (Ca), magnesium (Mg), available phosphorous (P), and total nitrogen (TN). These properties play key roles in nutrient availability, pH regulation, and soil structure, influencing soil fertility and overall soil health. By utilizing vis-NIR spectroscopy, we were able to accurately predict the soil indicators with good accuracy using the Cubist model (R2 = 0.35-0.93), offering a cost-effective and environmentally friendly alternative to traditional laboratory analyses. Using the seven soil indicators, we looked at three different approaches for calculating and predicting the SQI, including: (1) measured SQI (SQI_m), which is derived from laboratory-measured soil properties; (2) predicted SQI (SQI_p), which is calculated using predicted soil properties from spectral data; and (3) direct prediction of SQI (SQI_dp), The findings demonstrated that SQI_dp exhibited a higher accuracy (R2 = 0.90) in predicting soil quality compared to SQI_p (R2 = 0.23).
RESUMO
The integrated application of inorganic fertilizers, organic fertilizers, and biofertilizers helps sustain the nutrient pool and benefits the soil quality, thereby boosting plant health. The effect of different combinations of biofertilizers (consortium biofertilizer [CBF]-non-rhizobial PGPR), inorganic fertilizers, and organic fertilizers on soil health, growth, and yield of cowpea was evaluated by conducting a field experiment. The application of N100 FYM + CBF resulted in significantly higher populations of bacteria, fungi, PSB, and diazotroph, as well as soil dehydrogenase and alkaline phosphatase enzyme activities. However, the application of N100 FYM recorded a significantly higher actinomycetes population. The application of N100 FYM + CBF resulted in significantly higher soil OC, available nitrogen, phosphorus, and potassium. The soil pH was recorded to be highest in control, and soil EC was recorded to be lowest in control. The plant uptake of nitrogen, phosphorus, and potassium was significantly higher with N50 FYM + NP50 + CBF. The root-shoot biomass, number of leaves, nodules/plant, number of pods/plants, pod biomass, pod length, and pod width were significantly higher in treatment having N50 FYM + NP50 + CBF. However, the height of the plant, number of branches, and biomass of leaves were highest in treatment with N25 FYM + NP75 + CBF. The pod and stover yield were significantly higher in treatment with N50 FYM + NP50 + CBF. The results showed that the integrated application of non-rhizobial PGPR along with organic and inorganic fertilizer helps to improve overall soil health, quality, and plant growth of forage cowpea contributing to an increase in crop yield.
RESUMO
Exogenous carbon (C) inputs stimulate soil organic carbon (SOC) decomposition, strongly influencing atmospheric concentrations and climate dynamics. The direction and magnitude of C decomposition depend on the C and nitrogen (N) addition, types and pattern. Despite the importance of decomposition, it remains unclear whether organic C input affects the SOC decomposition under different N-types (Ammonium Nitrate; AN, Urea; U and Ammonium Sulfate; AS). Therefore, we conducted an incubation experiment to assess glucose impact on N-treated soils at various levels (High N; HN: 50 mg/m2, Low N; LN: 05 mg/m2). The glucose input increased SOC mineralization by 38% and 35% under HN and LN, respectively. Moreover, it suppressed the concentration of NO3--N by 35% and NH4+-N by 15% in response to HN and LN soils, respectively. Results indicated higher respiration in Urea-treated soils and elevated net total nitrogen content (TN) in AS-treated soils. AN-amended soil exhibited no notable rise in C mineralization and TN content compared to other N-type soils. Microbial biomass carbon (MBC) was higher in glucose treated soils under LN conditions than control. This could result that high N suppressed microbial N mining and enhancing SOM stability by directing microbes towards accessible C sources. Our results suggest that glucose accelerated SOC mineralization in urea-added soils and TN contents in AS-amended soils, while HN levels suppressed C release and increased TN contents in all soil types except glucose-treated soils. Thus, different N-types and levels play a key role in modulating the stability of SOC over C input.