The impact of cow dung augmentation on soil restoration and bio-accumulation of metals (Lead and Cadmium) in Pheretima posthuma (Annelida: Clitellata)

To investigate the role of cow dung in soil reclamation and bio assimilation along with bio accumulation of heavy metals in earthworm (P. posthuma) (N=900) earthworms were used and treatment groups of CD-soil mixture of different proportion of cow dung were designed. Nonlethal doses of lead acetate and cadmium chloride were added in treatment groups. Mature P. posthuma were released in each experimental pot maintaining the favorable conditions. The pH, carbon, nitrogen, phosphorus, exchangeable cations, and heavy metal level of each mixture was evaluated. The results indicated that bio-assimilation of Pb and Cd by P. posthuma were significantly (P ˂ 0.01) higher in different soil-CD treatments compared to control. Highest bio-assimilation of both metals was observed in T1 of both groups (Pb = 563.8 mg/kg and Cd = 42.95 mg/kg). The contents of both metals were significantly (P ˂ 0.05) lowered in casting. The nutrient concentration in the final castings of all soil-CD treatments were also equally transformed from less or insoluble to more soluble and available for plants, except for carbon level which increased with CD proportion. It is concluded that cow dung as organic matter has a positive effect on soil reclamation and bio-assimilation of metals by P. posthuma.

Influence of Vegetable and Fruit Wastes Vermicompost on the Growth and Yield of Black Gram (Vigna mungo L.)

Background: Composting is the process of breaking down of organic matter using living organisms which can be used as manure for soil conditioning. Vermicomposting is the rapid decomposition of biowastes using earthworm species which will enhance the growth and yield of plants. Methods: The vermicomposting of vegetable and fruit wastes was carried out during summer season (May-July) and by using the vermicompost a pot culture experiment was conducted in black gram for three months from August to October, 2019. The treatments consist of combinations of vermicomposted wastes and cowdung along with bioinoculants, Soil served as control. The biometric parameters such as root length, shoot length, fresh weight and dry weight on 15, 35, 55 DAS and yield characters like number of pods/plants, number of seeds/pods, pod length, weight of seed/pod, pod fresh weight and pod dry weight were recorded and statistically analysed. The present study has been attempted to convert the vegetables and fruit waste into compost as manure and analyse its effect on vegetative growth and yield parameters of Black gram (Vigna mungo L.). Result: The highest value of shoot length, root length, fresh weigh and dry weight were noted in fruit waste + cow dung + Pleurotus eous (APK1) + Trichoderma asperelloides + Eudrilus eugeniae on 15, 35 and 55 day after sowing (DAS) and the least was reported in control (only soil). The application of T8 treatment reported the highest yield characters which were followed by other treatments and control on 15, 35 and 55 DAS. The study concluded that T8 (F.W + cow dung + P. eous + T. asperelloides + Eudrilus eugeniae) is an effective biocompost for the growth and yield of black gram (Vigna mungo L.) which is eco-friendly.

Effectiveness of bioactive compounds in amending the soil infested with soil-borne Ralstonia solanacearum of potato

Three natural bioactive compounds, viz. cow dung, bee propolis and turmeric powder were applied to amend the Ralstonia solanacearum infested soil of potato. Sun dried cow dung @ 30 t/ha, aqueous extraction of turmeric powder @ 30 kg/ha and propolis @ 5 lit/ha were applied to the inoculated soil by mixing with field soil in SAU (Dhaka) and BARI (Gazipur). Data on pH, organic matter, total cfu/ml and avirulent cfu/ml of the treatment applied soil and per cent disease index (PDI) of bacterial wilt of potato were recorded. Significant difference in soil pH and per cent organic matter (OM) occurred in all the amended soil as compared to control. A decreased total cfu/ml of R. solanacearum occurred in all the treated soil, but propolis (8.2 X 107) and cow dung (1.1 X 108) showed the lowest count. However, in increasing the avirulent count of R. solanacearum, turmeric powder (1.8 X 109) showed the highest count compared to other amended soil. Significant disease reduction over control was also observed in all the treatments, but propolis (45.65%) and turmeric powder (43.48%) showed the best results in wilt disease reduction. J. Biodivers. Conserv. Bioresour. Manag. 2021, 7(1): 43-50

Influence of various commercially available organic manures on growth, yield and nutrient accumulation in mint plants (Mentha sp.)

A pot experiment was set up using completely randomized design (CRD) to compare the influences of different commonly available organic manures in the markets of Dhaka, Bangladesh on the growth parameters and nutrient contents in Mint plants (Mentha sp.). Eight different manures were used as treatments for the comparison, viz. ACI, Alo, Annopurna Vermicompost, Cow dung, Kazi, Mazim, Modern Vermicompost and Trichocompost GBD, along with a control, taking three replications of each treatment. After 2.5 months (75 days) the plants were harvested. Trichocompost GBD showed the highest average number of leaves (130.33 plant-1), plant height (27.67 cm plant-1), number of branches (11.00 plant-1) and number of stolons at harvest (1.67 plant-1). The maximum average single leaf area (2.01 cm2 plant-1) and fresh weight (1.68 g plant-1) were observed in Kazi. ACI was observed to have the highest dry weight (0.26 g plant-1), whereas cow dung had the longest root (8.57 cm plant-1). Nutrient accumulation in leaf and stem exhibited the highest N in ACI, highest P and K in Alo, and highest S in Kazi. Correlation analysis of the explored traits with nutrient concentration of plant shoots was performed to elucidate the impact of plant nutrient contents on the analysed parameters. J. Biodivers. Conserv. Bioresour. Manag. 2021, 7(1): 73-84

What Makes Cow-Dung Stabilised Earthen Block Water-Resistant

The water-resistance of cow-dung has made it a widely used stabiliser in traditional earthen structures in several Asian and African countries. Multiple studies have shown an improvement in water-resistance with the addition of cow-dung, but none provides insight into this behaviour. The present study investigates the water-resistance behaviour of cow-dung stabilised earthen blocks through an extensive experimental programme to identify and characterise the components of cow-dung responsible for its water-resistance. Fresh cow-dung was collected and separated into fibres (>63 μm), medium-sized microbial aggregates (1-63 μm) and small-sized microbial aggregates (0.5-7 μm). Each component was mixed with soil and samples were prepared at different water contents (optimum water content corresponding to the highest dry density and water content higher than optimum) and compacted with 2.5 MPa force to prepare compressed blocks. The water-resistance of these blocks was evaluated through the immersion and modified drip/rain test. It was found that the small-sized microbial aggregates are almost entirely responsible for water-resistance behaviour of cow-dung stabilised earthen blocks. Small-sized microbial aggregates were further characterised by gas chromatography, mercury intrusion porosimetry, N2- BET surface area, zeta potential measurement and electron microscopy. The results indicate that the small-sized microbial aggregates are composed of clay-sized negatively charged particles that are rich in fatty acids. The hydrophobicity of these particles is hypothesised to be responsible for water-resistance behaviour. These insights are further used to produce stabilised blocks that performed at least 30 times better than the unstabilised blocks in both water-resistance tests. The study concludes with practical recommendations for the use of wet cow-dung over dry cow-dung and a reduction of fibre content to increase the water-resistance of earthen blocks.

Biological Stabilisers in Earthen Construction: A Mechanistic Understanding of their Response to Water-Ingress

Earthen construction is re-gaining popularity as an ecological and economical alternative to contemporary building materials. While building with earth offers several benefits, its performance due to water ingress is a concern for its widespread application. This limitation is often solved by adding chemical stabilisers such as Portland cement and hydraulic lime. Chemical stabilisers are a subject of widespread debate as they increase the cost and embodied energy of the structure, and reduce the desirable characteristics of raw or unstabilised earth. This along with perceived environmental performance, renewability, and proven effectiveness in traditional earthen construction has led to a growing interest in biological or organic stabilisers. Although the strengthening mechanism of biological stabilisers is widely covered in scientific studies, discussion regarding the water-resistance is limited. This review aggregates the research from the field of earthen construction and geotechnical engineering and extends it to explain the possible mechanism responsible for the water-resistance behaviour of biologically stabilised earthen materials. This study includes a wide range of traditional and industrial biological stabilisers derived from animals (cow-dung, casein, chitosan), plants (starch, guar gum, cactus mucilage, lignin, tannin) seaweeds (alginate, agar, carrageen) and microbes (xanthan gum, gellan gum). A conceptual model of water-ingress in unstabilised earthen blocks is proposed and the response of biological stabiliser to water ingress and related physico-chemical and physical factors is discussed using the model at microscale (stabiliser interaction with clay, sand) and macroscale (hydraulic conductivity of block). Properties of stabilisers such as hydrophobicity, stability under wet conditions or interaction with cations have a dominant effect on the overall response to water ingress. Key gaps have been identified in the existing knowledge that are necessary to investigate in order to understand the water-resistance behaviour comprehensively. The study concludes with a brief assessment of biological stabilisers based on their performance and feasibility to use in contemporary earthen construction.

Sustainable Use of Macrotermes spp. to Improve Traditional Poultry Farming through an Efficient Trapping System in Burkina Faso

This study aimed to promote the use of termites as feed in traditional poultry farming by developing sustainable and inexpensive termite trapping techniques. Various tests were carried out in Burkina Faso to improve the traditional technique of trapping termites of the genus Macrotermes using a reversed container filled with organic matters. We studied the effect of containers’ types, substrates, habitats, harvesting times, duration of trap deposition, and season on the quantity of termites trapped. Calabashes and terra cotta pots trapped more termites than iron boxes, but calabashes were quickly destroyed by termites. The quantity of termites harvested increased proportionally with the volume of the pot and was higher in a cultivated habitat than in a forest, despite the higher number of termite mounds in the forest. The quantity of termites harvested was lowest in the cold-dry season and highest during the rainy season, however, sizeable amounts of termites were collected throughout the year. Among six substrates and mixtures of substrates tested, maize cobs trapped the highest number of termites and cow dung the lowest. The best time of harvest varied among seasons and, if substrates are abundant, it is more efficient to empty the containers on a daily basis.

Surveillance on Emission of Herbal Woods and Cow Dung for Refinement of Atmosphere with Vedic Mantra

Earth's atmosphere is made of two gases Nitrogen and Oxygen. Five major air pollutants are Ground level Ozone, Airborne particles or aerosols, Carbon monoxide, Sulfur dioxide, Nitrogen dioxide. Air pollutants risky to human health are Ground level Ozone and Aerosols. They are the main ingredients of Smog . The ground level ozone is formed when sunlight reacts with certain chemical emissions like nitrogen dioxide, carbon monoxide or methane These chemicals are emitted from industrial waste, car exhaust, gasoline vapors etc. Air quality is measured with the Air Quality Index. An AQI under 50 is considered as good air quality however as the AQI number increases , it becomes a concern for human health . Researcher measured the PM level (PM 2.5 and PM 10), temperature, Humidity and other related parameters continuously on different woods in different times in a fixed size room and constrained environment to establish that Yagya is a reliable source to reduce environment pollution .

Potential of Earthworm (Perionyx Excavatus) in food treatment in Ho Chi Minh City

In Ho Chi Minh City, Vietnam, there are about 9 thousand tons of domestic waste every day and 73% of them are treated by using landfill sites [2]. With the population growth rate in recent years, the generated waste volume will then increase in the future and is estimated to reach a total of around 13 thousand tons that could cost Ho Chi Minh City about 260 thousand dollars in treating this waste in 2025 [3]. Although this treatment method is not without advantages, the downsides will be far more significant. Moreover, in recent years, the cultivation of Perionyx Excavatus, a species that had been reported to have the ability to treat organic waste in some foreign articles, has become increasingly popular in Vietnam. So, this research was aimed to evaluate the potentiality of Earthworm (Perionyx Excavatus) for food waste management of households in Lab-scale in Ho Chi Minh City, Vietnam. According to this study, the average outdoor humidity and temperature of Ho Chi Minh City are higher than optimal conditions to raise Earthworm. In addition, the percentage of biomass is highest when rising the proportion of food waste and cow dung 4:6, respectively. It’s a point for encourage the applying Earthworm (Perionyx Excavatus) for food waste management in Ho Chi Minh.