Commercial Farms Research Articles

Association Between Dairy Production System and Milk Functionality Based on Analysis of miRNAs in Exosomes from Milk.

Dairy farming practices significantly affect the nutritional and functional properties of milk. This study compares miRNAs in milk exosomes from extensive and intensive dairy systems and explores their potential implications for human consumers. Extensive systems are believed to produce milk of higher quality with better animal welfare compared to intensive systems. Milk samples from eight extensive and nine intensive dairy farms were analysed. Milk-derived extracellular vesicles were isolated through sequential ultracentrifugation and characterised through Dynamic Light Scattering and Nanosight to determine the size and the concentration of the extracellular vesicles, in addition to immunoblotting to ensure the presence of exosome-specific proteins in their membrane. miRNA levels were quantified using RT-qPCR, and metabolic pathways associated with miRNAs showing significant differences between farm groups were analysed. EVs from extensive farms had higher concentrations. Notably, bta-miR-451 levels were significantly higher in milk from extensive farms (p = 0.021). Like human miRNA hsa-miR-451, it is linked to pathways related to Parkinson's disease and cancer. Our research suggests that milk production in extensive systems not only provides socioeconomic and environmental benefits but may also have positive effects on human health. Further research is warranted to explore the bioactive potential of these miRNAs and their implications for human health.

A cross-regional examination of camelid herding practices in Peru from 900 BCE to 1450 CE: Insights from stable isotopes in camelid bone collagen and fiber.

The economic, socio-political, and cultural significance of camelids in the Andean region is well-recognized, yet an understanding of their management evolution over pre-historical periods remains limited. This study aims to fill this gap by conducting the first cross-regional assessment of camelid pastoralism in Peru from 900 BCE to 1470 CE, using stable carbon and nitrogen isotopic compositions from the bone collagen and fibers of 577archaeological camelids across 21 sites. This research investigates the spatio-temporal shifts in camelid dietary habits, focusing on how the rise of intensive agriculture may have influenced change and led to the evolution of distinct roles for camelids in coastal versus non-coastal Andean economies. Our analysis indicates an increase in δ13C values over time on the coast, suggesting a shift towards maize-based camelid diets. Conversely, δ13C values decrease over time in highland environments, suggesting camelids consumed relatively more wild C3 forage and/or cultivated crops such as tubers. The study also reveals a significant positive relationship between latitude and δ15N values, suggesting increasing environmental aridity enriches δ15N in bone collagen. After controlling for this latitudinal effect, we observe a rise in δ15N values in both coastal and non-coastal camelids, suggesting that in later periods camelids may have been foddered in agricultural fields that were enriched with guano or dung fertilizer used to intensify production. Importantly, this research uncovers a distinct dietary divergence between coastal and inland camelids. The observed divergence in diets suggests contrasting socio-economic uses of camelids, where coastal camelids were predominantly involved in ceremonial and political activities, while those in non-coastal areas were crucial to the subsistence economy.

Improving sustainability of rice-canola rotation through water and nitrogen management in a humid region

Intensive cropping systems face significant environmental and economic challenges due to current water and nutrient management practices. This study addresses the limited research on optimizing these practices in rice-canola rotations, focusing on enhancing sustainability through improved water and nitrogen (N) management. Utilizing the DSSAT crop growth model, we evaluated three irrigation scenarios for rice- I1 (100 % irrigation requirement: IR), I2 (80 % IR), and I3 (60 % IR)-alongside three N application levels: N1 (30 % below RAN: regional average N), N2 (RAN), and N3 (30 % above RAN). Key sustainability indicators, including water productivity (WP), nitrogen use efficiency (NUE), and economic productivity, were analyzed. The DSSAT model demonstrated strong predictive accuracy, with yield differences of only 236 kg ha⁻¹ for rice and 121 kg ha⁻¹ for canola between observed and simulated values. A 40 % reduction in water use increased rice yield to a maximum of 5654 kg ha⁻¹ under I3N2 conditions. Additionally, this reduction in water consumption resulted in a 27 % decrease in production costs, significantly enhancing WP, net benefits, and gross benefits of rice by 46.7 %, 43.1 %, and 47.9 %, respectively. Conversely, a 30 % increase in N application for canola correlated with a 9 % yield increase, underscoring the importance of tailored N strategies. Furthermore, N3 raised WP, NUE, net benefits, and gross benefits of canola by 6.7 %, 1.4 %, 9.1 %, and 9.2 %, respectively, compared with current N application level. Overall, this study illustrates the potential for substantial water savings in rice cultivation while recommending stable or reduced N application levels. These management strategies enhance farm performance, lower production costs, and contribute to the sustainability of rice-canola cropping systems, promoting both agricultural productivity and environmental stewardship.

Perennial crops shape the soil microbial community and increase the soil carbon in the upper soil layer

Soil biodiversity is threatened by intensive agriculture that relies on annual grain crop production, thus leading to a decline in soil functions and ecosystem services. Perennial grain crops have a positive impact on the soil microbial community, but the responsive microbial groups and the magnitude of their response remain uncertain. To elucidate this, we analysed soil microbial biomass and community composition, bacterial growth and soil total carbon in five crops: organic perennial intermediate wheatgrass (IWG, Thinopyrum intermedium, Kernza®), organic IWG-alfalfa intercrop, organic biennial grass-legume mixture, organic annual wheat or rye and conventional annual wheat. The analysis was carried out at three time points under two growing seasons at four different soil depths. Five years after establishment, IWG had greater amounts of soil total fungi and bacteria, and of arbuscular mycorrhizal (AM) fungi, saprotrophic fungi, gram-negative (G−) and gram-positive (G+) bacteria compared to annual wheat. Crop perenniality influenced the soil microbial community structure although precipitation, soil temperature and water content were the main drivers of the patterns of and temporal variations in the microbial community. Perennial crops, with reduced tillage and low nitrogen input management increased the proportions of fungi relative to bacteria, AM fungi to saprotrophic fungi, G− bacteria to G+ bacteria, and the growth rate of total bacteria. This resulted in a more active soil microbial community with higher microbial biomass than annual wheat and contributed to the increased soil total carbon storage in the 0–5 cm soil layer in a humid continental climate. The findings emphasize the importance of combining a no tillage strategy with long-term vegetation cover to increase soil quality.

Impact of Feed Bunk Space on the Prevalence of Torsion and Foreleg Distal Asymmetry in Holstein Cows.

Leg torsion and distal asymmetry (LTDA) among cows reared on intensive farms in the Comarca Lagunera region of northern Mexico may be indicative of underlying health concerns. To ascertain whether the incidence of LTDA is associated with trough measurements and with productive, reproductive, and disease variables, the prevalence of LTDA was determined in lactating dairy cows. The data were derived from two intensive dairy farms in northern Mexico (G60: 2043 cows in 13 pens with 142.0 m of linear feed bunk space and 65.0 m of pen depth; G100: 2227 cows in 12 pens with 215.0 m of linear feed bunk space and 49.0 m of pen depth). The cows were observed over the course of a week to identify any macroscopic lesions indicative of LTDA. Cows exhibiting lesions were assigned a value of "1", while those without lesions were assigned a value of "0". Furthermore, data regarding other limb diseases (LDs) were collected and subjected to analysis. A comparison was conducted to ascertain the impact of reproductive, productive, and feed bunk size variables on the prevalence of LTDA and other LDs. To ascertain the prevalence of LTDA and LDs, a chi-squared test was employed. The prevalence of LTDA was found to be 27.6% (G60: 31.4%, G100: 22.4%). No association was identified between LTDA and the variables included in the study. However, a correlation was identified between LDs and the following variables: total width, distance from the edge, width from the feed bunk to the tramp, and the presence of a manure crust on the walls. Principal component analysis (PCA) was conducted to examine the correlation between LDs and various factors at the farm and pen levels. The findings indicated that the distance from the feed bunk to the trough, the presence of manure crusts on the walls, and the breeding time were associated with LDs in G100, as well as in three of the twelve pens (302, 306, and 308) within G100. The findings suggest that the prevalence of LDs is associated with an increase in the width of the feed bunk and the width of the manure crust on the walls, particularly in pregnant cows. The results permit the conclusion that LTDA and LDs are associated with the measurements of the feed bunks, the absence of manure cleaning of the feed bunks, and gestation. This association gives rise to significant health issues for Holstein cows on these farms, with more than one in four cows affected. To reduce the prevalence of LTDA in lactating dairy cows, it is recommended that the standard measurements for feed bunk design be adhered to. This will reduce the prevalence of LTDA and LDs, promote the cleaning protocols to avoid the accumulation of manure crusts, and facilitate close monitoring of pregnant cows, thereby alleviating the impacts of these foot pathologies on animal welfare.

Family Farm Resilience during the COVID-19 Pandemic in Indonesia: Case Studies on Organic and Conventional Farming

The COVID-19 pandemic has brought additional stressors to Indonesian family farms, which are already subject to drought, flood, landslide, pest attack, and market price fluctuations. This study aims to analyse family farms’ resilience to the stressors caused by the COVID-19 pandemic using Henry’s family resilience model. Applying a qualitative approach, this study collected data using focus group discussions in two villages in East Java and a village in Center Java. The data was analysed using thematic analysis. We discovered that stressors related to the COVID-19 pandemic are lower demand on agricultural products and lower income among farmers. Organic and conventional farmers have different protection and vulnerability factors. Organic farmers are able to reach buyers directly using social media amid COVID-19 restrictions while conventional farmers still rely on sales through middlemen. The adaptive process of farming families is influenced by social psychological factors within the family such as meaning, emotion, control, and maintenance systems. This study suggests that family farmers have to be empowered in terms of their innovative production in current stressors and increase their access to the market as a priority for agricultural extension programmes.

Appropriate sampling to aid on-farm assessments of the haplotype composition of Zymoseptoria tritici populations.

Zymoseptoria tritici causes Septoria tritici blotch (STB), which is the biggest threat to wheat in the UK. Azole fungicides have been used since the 1980s to control STB, but resistance to these chemicals is now widespread. The main resistance mechanism is based on the accumulation of CYP51 mutations, with 33 mutations reported. Hence, farmers need an accurate estimate of the haplotype composition of Z. tritici populations to develop effective fungicide treatments and resistance management. Isolates from Z. tritici lesions were collected from three fields across three commercial farms using two sampling approaches. Analysis of the isolate sequences revealed that the number of distinct haplotypes and the haplotype composition of the most dominant haplotypes varied only between and not within farms. Conventional W-shaped and point sampling both found the same percentage of distinct haplotypes and frequencies of the six most dominant haplotypes. The results from this survey suggest that farm-resistance-management strategies should be based on farm-specific rather than national data, and that sampling within a single field is sufficient. W-shaped sampling is often recommended in sampling approaches, but this survey finds no evidence of this approach being more appropriate for detecting a greater percentage of distinct haplotypes which may aid the discovery of potential new resistance threats. © 2024 Fera Science Ltd. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Economic Assessment of Hydrologic Ecosystem Services in Morocco’s Protected Areas: A Case Study of Ifrane National Park

This study delves into the complex interplay between land use dynamics, hydrological services, and intangible benefits within the context of Ifrane National Park (INP) in Morocco. Due to its extensive mountain forests and numerous wetlands, INP is a crucial contributor to the nation’s water supply and a vital source of hydrological ecosystem services (HES). However, climate change and evolving land use patterns have led to diminishing water resources and the desiccation of certain wetlands. This research used the Integrated Valuation of Ecosystem Services and Tradeoffs software (InVEST 3.10.2) for HES quantification and environmental economics approach for monetization to comprehend how HES values respond to challenges posed by urbanization, intensive agriculture, and other land use alterations. This work underscores INP’s role as a significant “water tower”, emphasizing the evolution of its services amidst challenges. Our findings reveal an annual decrease in HES economic value by USD 4000. This economic assessment serves as a compelling tool to enlighten decision-makers and park users about the imperative need to preserve natural ecosystems and use water resources judiciously. It advocates for investments in conservation and restoration within protected areas to sustain these vital services.

Effect of Gestational Direct-Fed Microbials Supplementation on the Metabolic Profile in Periparturient Dairy Cows.

This study was conducted at a commercial dairy farm in Queensland, Australia to evaluate the effects of feeding a lactic acid bacteria-based direct-fed microbial (DFM) during gestation on the metabolic profile of periparturient dairy cows and its effects on milk production and body weight. A total of 150 multiparous Holstein cows were randomly selected based on parity (2.3) and days in milk (130 DIM) and divided into two groups of 75 cows each (control and DFM). The control cows were assigned to a basal diet consisting of a silage-based partial mixed ration (PMR), concentrate fed in the dairy twice a day, and ad libitum pasture. The DFM group received the same basal diet supplemented with three strains of Lactobacillus top-dressed in the feed. The DFM supplementation continued during both the dry period and the subsequent lactation. A subset of 82 cows (40 control and 42 DFM) were monitored during the calving season (March to July 2022) to assess the metabolic profile and postpartum performance. Blood samples were collected during the periparturient period (-4 to -2 w prepartum, around calving, and at weeks 1, 3, and 6 postpartum) to measure the levels of metabolites, enzymes, and minerals. Overall, the serum glucose, NEFA, and chloride levels were higher, while protein and urea were lower in cows supplemented with the DFM (p < 0.005). The pre-calving levels of glucose were higher and the total bilirubin, urea, and BHB were lower in cows supplemented with DFM than in the control (p < 0.05). The post-calving levels of glucose and Mg were also higher in the DFM cows than in the control cows (p < 0.05). Average milk production at 110 DIM was significantly higher in the DFM cows compared to control cows (p = 0.03). Although the total milk production over 305 days was numerically greater in the DFM cows, the difference was not statistically significant (p = 0.3), whereas the milk protein percentage was higher in the control cows (p = 0.03). The body weight of the DFM cows was greater during the periparturient period (p = 0.001) than that of the control cows. In the DFM cows, glucose levels had a positive correlation (r = 0.16) with milk yield, at 110 DIM, while serum total protein had a positive correlation with body weight (r = 0.32) (p < 0.05). In conclusion, feeding Lactobacillus-based DFM during gestation can positively influence the metabolic profile of periparturient cows, which, in turn, may affect the milk production and body weight of postpartum dairy cows.

Engaging commercial dairy demonstration farmers in farmland biodiversity management communication

ABSTRACT Purpose: This paper presents the process, experiences and outcomes of piloting various communi­cation activities relating to farmland biodiversity management with 11 Irish dairy demonstration farmers. Design/Method/Approach: A 17-month cycle of action research, which included a 12-month communication activity pilot, researcher diary entries, and baseline and endline semi-structured interviews with participating demonstration farmers. Findings: The integration of farmland biodiversity management into an on-farm group meeting was identified by the demonstration farmers as most influential on their decisions to make changes to biodiversity management on their farms, while the integration of farmland biodiversity management into online group meetings was ranked lowest. Positive attitude and practice changes were identified over the communication activity pilot. Practical Implications: Awareness of communication activities that effectively engage demonstration dairy farmers on farmland biodiversity management, with foundation and guidance for the implementation of such activities with a wider cohort of farmers. Theoretical Implications: Identification of the potential to positively influence on-farm biodiversity management change through co-creative, participatory communication activities. Originality/Value: Addresses communication on farmland biodiversity management with demonstration dairy farmers in Ireland.

The prevalence and shedding of porcine epidemic diarrhea virus in intensive swine farms of China from 2022 to 2023

Porcine epidemic diarrhea has emerged as a significant threat to the global swine industry. The shedding and exposure status of porcine epidemic diarrhea virus (PEDV) in intensive farms is not completely understood. In this study, a total of 56,598 clinical samples collected from 256 intensive pig farms in 20 provinces in China from 2022 to 2023, were evaluated for PEDV using quantitative real-time PCR. The overall PEDV prevalence was 11.78 % and 28.45 % at the sample and farm levels, respectively, which are relatively high in Northern China and the fourth and first quarter of the year. The PEDV-positive rates and viral loads in suckling piglet herds were higher than those in growing-finishing pigs and multiparous sows. Meanwhile, 15.61 % of pig pens, 9.51 % of corridors, 9.4 % of office areas, 9.23 % of production personnel, and 8.33 % of pig cart driver samples were positive for PEDV, indicating potential biosafety gaps in intensive pig farms. In addition, 93.41 % of inguinal lymph node tissue samples contained viral nucleic acids, revealing a possible persistent infection of PEDV in pig herds. Our study presents the first report of the large-scale detection of PEDV in intensive pig farms, which constitutes indirect evidence of virus circulation in pig herds. This study provides valuable data for preventing and controlling PEDV infection in the future.

Optimal aquarium shape for rearing male Siamese fighting fish (Betta splendens)

The aggressive behavior of male Siamese fighting fish (Betta splendens) necessitates their rearing in isolation in small aquaria. For intensive production, the major concerns are growth promotion and feed utilization. The small aquaria are connected to save space but little is known about the suitable characteristics of aquaria for this species. In this study, solid-red male Siamese fighting fish (0.57–0.58 g body weight) were individually housed in aquaria that had square (SQ), rectangular (RE), equilateral triangular (ET), or right triangular (RT) cross sections. The water in the aquaria had the same depth (6 cm) and volume (180 mL). At the end of the eight-week trial, fish housed in the ET and RT aquaria exhibited superior growth rate and feed utilization to fish housed in SQ or RE aquaria (P < 0.05). No differences in morphometrics, skin coloration, muscle quality, and whole-body composition were observed. Protein- and lipid-digesting enzyme activities, as well as amylase/trypsin ratios, indicated differences in feed utilization that were correlated with aquarium shape. The findings of our study indicated that the triangular aquaria were more suitable for rearing this fish in isolation. This study could be used as an animal protocol for experimental set-up, to improve betta fish farm management, and also for the development of intensive farming systems for this species.

Unveiling the Molecular Mechanisms Regulating Muscle Elasticity in the Large Yellow Croaker: Insights from Transcriptomics and Metabolomics.

The large yellow croaker (Larimichthys crocea) is an important economic fish in China. However, intensive farming practices, such as high stocking densities, suboptimal water quality, and imbalanced nutrition, have led to a decline in muscle quality. Muscle elasticity is a key texture property influencing muscle quality. Herein, transcriptomic and metabolomic analyses were performed on four groups: male high muscle elasticity (MEHM), female high muscle elasticity (MEHF), male low muscle elasticity (MELM), and female low muscle elasticity (MELF), to explore the molecular regulation underlying muscle elasticity in the large yellow croaker. Transcriptomics identified 2594 differentially expressed genes (DEGs) across the four groups, while metabolomics revealed 969 differentially expressed metabolites (DEMs). Association analysis indicated that the valine, leucine, and isoleucine biosynthesis pathways were significantly enriched between the MELF and MEHF groups; 2-Oxoisovalerate and L-Valine were DEMs; and the gene encoding L-threonine ammonia-lyase was a DEG. In the MELM and MEHM groups, pathways such as arginine biosynthesis; arginine and proline metabolism; and valine, leucine, and isoleucine degradation were significantly enriched. 4-guanidinobutanoate, L-aspartate, N-acetylornithine, and L-leucine were among the DEMs, while the DEGs included glul, gls, srm, hmgcs, and aacs. These findings provide insights into the molecular mechanisms controlling muscle elasticity, representing a theoretical foundation to breed high-quality large yellow croakers.

Change in Bee Pollinators’ Guild Over the Time in the Punjab: State Under Intensive Agriculture

Change in Bee Pollinators’ Guild Over the Time in the Punjab: State Under Intensive Agriculture

Microbiology, induction, and management practices to mitigate lameness caused by bacterial chondronecrosis with osteomyelitis in broiler chickens

Bacterial chondronecrosis with osteomyelitis (BCO) lameness is the most prevalent skeletal disorder in poultry, implicated by the inherent risk of the high growth rate of modern broilers. The non-synchronization of massive body mass accretion vs maturation of the structural bone induces vulnerability to bone microfracture and immunosuppression, leading to bacterial necrosis in the skeletal and thoracic vertebral bones, leg paralysis, and eventual death. BCO lameness also imposes animal welfare issues and confers food safety risks. A study in 20 broiler farms in Australia recorded 28% BCO lesions of the necropsied birds, while a study in commercial flocks in Europe reported 19% moderate-to-severe lameness symptoms. The high incidence of lameness in commercial broiler farms reduces production value and leads to a huge economic loss in the poultry industry. Managing BCO lameness in broiler poultry is more challenging than that of other species because the peak of lameness incidence emerges at the marketing age of broilers. Moreover, curative treatment of the affected broilers is arduous due to their larger populations but shorter production cycles. Thus, condemnation of clinically lame birds has been a common practice in broiler farms to prevent the transmission of highly contagious BCO throughout the broiler populations. This practice decreases the production value and increases the economic forfeits. Therefore, presenting intervention measures for managing and controlling BCO in broiler poultry is necessary. Knowledge of etiological agents, pathogenesis, detection, and experimental lameness models to evaluate the efficacy of the intervention measures is highly important in presenting approaches to mitigate BCO lameness. Thus, this review focuses on microbiology studies of BCO, models of creating experimental lameness, and intervention measures mitigating BCO lameness in broiler chickens.

High-yield rice with rich nutrition and low toxicity can be obtained under potato-rice cropping system.

Rice is often rotated with dryland crops to produce sufficient foodstuff, as rice is the main food crop of humans. In order to verify whether under the intensive rice-based cropping system, high yield and good quality of rice can be achieved simultaneously to ensure food security. Five long-term paddy-upland rotations - wheat-rice (WR), rapeseed-rice (RR), garlic-rice (GR), broad beans-rice (BR) and potato-rice (PR) - were conducted from 2014 to investigate rice yield, along with the profiling of 24 elements in rice grain. Mg, Zn, Cu, As, Mo and Sb concentrations were highest in the aleurone layer, and Ag and Cd concentrations showed little variation among different parts of the rice grain. Al, Ti, V, Si, Fe and Tl concentrations in the endosperm under GR were higher, while the Se concentration under PR was the highest. Furthermore, the yield of GR and PR were higher than the other three rotations with N supplementation, and the sustainable yield index of PR and WR were larger than 0.8. When we consider the concentration of toxic (As, Cd and Pb) and nutrient elements (Ca, Fe, Zn, Se, Cu and Mg) in the endosperm and grain yields, PR can simultaneously achieve high yield, high nutrition and low toxicity with different nitrogen treatments. Here we provide novel insights regarding the selection of rice-based cropping systems, focused on producing nutritious and safe rice with high grain yield. © 2024 Society of Chemical Industry.

Anomalous white shrimp detection in intensive farming based on improved YOLOv8

Timely detection of anomalous shrimp is crucial for ensuring farming safety. Therefore, this study developed an effective model to detect abnormal shrimp behaviors, including curling, floating, leaping, cannibalism, and death. The proposed model uses YOLOv8 as the baseline, adjusts network parameters to align with the characteristics of abnormal shrimp, employs content-aware reassembly of features (CARAFE) to preserve more semantic information, and utilizes dynamic convolution to enhance the network's expressiveness. Achieving a 97.8 % mAP@0.5 and 96.1 % F1 score on a custom dataset, the model demonstrated superior detection performance and a smaller size compared with Faster-RCNN, single-shot multi-box detector (SSD), YOLOv5, YOLOv6, and YOLOv7. Based on the proposed model, we developed an abnormal shrimp monitoring system with significant potential to benefit white shrimp cultivators.

Conservation agriculture improves soil health and sustains crop yields after long-term warming

Climate warming threatens global food security by exacerbating pressures on degraded soils under intensive crop production. Conservation agriculture is promoted as a sustainable solution that improves soil health and sustains crop yields in a changing climate, but these benefits may be affected by long-term warming. Here, we investigate the effects of conservation agriculture compared to conventional agriculture on 17 soil properties, microbial diversity and crop yields, during eight-years’ experimental warming. An overall positive effect of warming on soil health over time under conservation agriculture is characterized by linear increases in soil organic carbon and microbial biomass carbon. Warming-triggered shifts in microbial biomass carbon and fungal diversity (saprogen richness) are directly linked to a 9.3% increase in wheat yields over eight years, but only under conservation agriculture. Overall, conservation agriculture results in an average 21% increase in soil health and supports similar levels of crop production after long-term warming compared to conventional agriculture. Our work provides insights into the potential benefits of conservation agriculture for long-term sustainable food production because improved soil health improves resilience to the effects of climate warming.

Greenhouse gas emissions during alfalfa cultivation: How do soil management and crop fertilisation of preceding maize impact emissions?

ContextThe use of alfalfa in rotation with intensive crops is common practice to mitigate the physical and chemical issues arising from intensive farming practices. However, there is a dearth of studies on this practice. Given the current concern regarding climate change and the significant impact agriculture has on greenhouse gas (GHG) emissions, understanding the emissions associated with this practice, as well as the most suitable soil and crop management techniques for their mitigation, is of paramount importance. ObjectiveThe present study aimed to (i) quantify emissions of N2O, CO2 and CH4 in an alfalfa crop following a maize cropping scenario; (ii) to determine which tillage system generates the lowest GHG emissions, and; (iii) to determine how N fertilisation from a preceding intensive maize crop affects GHG emissions during alfalfa cropping period. MethodsA three-year field experiment (2019, 2020 and 2021) was conducted to assess the emissions of N2O, CO2 and CH4 from alfalfa cultivation following a three-year period of irrigated maize. Two soil management practices (no-tillage and conventional tillage) were implemented during both the maize cropping period and the alfalfa establishment. Additionally, the nitrogen (N) fertilisation rates applied to the preceding maize crop were included as a treatment (0, 200, and 400 kg N ha⁻¹, corresponding to zero, medium, and high fertilisation levels, respectively) in a randomized block design with two factors. ResultsEmissions of N2O in alfalfa ranged from 0.05 to 0.32 mg N2O-N m⁻² day⁻¹, being significantly higher only during first month of sampling in the treatments that had received fertilisation. CO2 emissions ranged from 1158 to 4258 mg CO2-C m⁻² day⁻¹. Year-average CH4 fluxes were −0.27 g C ha⁻¹ day⁻¹. The average total dry matter produced by alfalfa was 17700 kg ha⁻¹ year⁻¹, being higher for the no-tillage treatment, though significantly so only during first month of sampling. ConclusionsUnder Mediterranean conditions, the tillage system and mineral N fertilizer rates have a relative effect on greenhouse gas emissions during the alfalfa cropping period. Plots without N fertilization initially produced lower N2O emissions and higher total dry matter, resulting in the lowest scaled emissions. For the tillage treatment, no significant differences were found in emission dynamics, which may be due to the fact that alfalfa does not involve soil disturbance, leading to a homogenization of the treatments. However, the NT treatment showed lower scaled emissions due to higher yields in the first year. Therefore, alfalfa cultivation is characterized by low GHG emissions, high yields, and a notable capacity to mitigate the negative effects of previous intensive crops. SignificanceThis study provides data on GHG emissions during alfalfa cropping in the typical Maize-alfalfa crop rotation under Mediterranean irrigated systems, which is useful for new agricultural policies aimed at reducing pollution in the agricultural sector. Additionally, it demonstrates the capability of this crop to mitigate adverse agronomic and environmental conditions caused by preceding intensive farming practices.

Potential of integrated multitrophic aquaculture to make prawn farming sustainable in Bangladesh

Farmed freshwater prawn (Macrobrachium rosenbergii) and black tiger shrimp (Penaeus monodon) comprise a significant portion of Bangladesh’s seafood exports, raising concerns about their environmental impacts. Freshwater prawn farms, which require a relatively high amount of feed supply, release 1.0 MT CO2-equivalents/year, equating to 18.8 kg CO2e/MT prawn, contributing significantly to global warming and climate change risks. Integrated Multi-Trophic Aquaculture (IMTA) offers an alternative farming method to conventional prawn farming systems, as it minimizes greenhouse gas (GHG) emissions and climate change impacts. Systematically reviewing 112 scientific articles on IMTA, this article offers recommendations for adopting IMTA to promote sustainable freshwater prawn farming in Bangladesh. IMTA is undergoing extensive experimentation and practice in many parts of the world, offering economic benefits, social acceptability, and environmental sustainability. In addition to native prawn species, various indigenous organic extractive freshwater mollusks, and inorganic extractive plants are available which can seamlessly be used to tailor the IMTA system. Extractive organisms, including aquatic mollusks and plants within prawn farms, can capture blue carbon effectively lowering GHG emissions and helping mitigate climate change impacts. Aquatic mollusks offer feed for fish and livestock, while aquatic plants serve as a dual food source and contribute to compost manure production for crop fields. Research on IMTA in Bangladesh was primarily experimented on finfish in freshwater ponds, with the absence of studies on IMTA in prawn farms. This necessitates conducting research at the prawn farmer level to understand the production of extractive aquatic mollusk and plants alongside prawn in the prawn-producing regions of southwestern Bangladesh.