Decline in extractable antibiotics in manure-based composts during composting

A wide variety of antibiotics have been detected in natural water samples and this is of potential concern because of the adverse environmental effects of such antibiotic residues. One of the main sources of antibiotics effluence to the surrounding environment is livestock manures which often contain elevated concentrations of veterinary antibiotics (VAs) which survive digestion in the animal stomach following application in animal husbandry practices. In Korea, livestock manures are normally used for compost production indicating that there is potential for antibiotic release to the environment through compost application to agricultural lands. Therefore, reduction of the amount of VAs in composts is crucial. The purpose of this study was to understand the influence of the composting process and the components of the compost on the levels of three common classes of antibiotics (tetracyclines, sulfonamides, and macrolides). Composted materials at different stages of composting were collected from compost manufacturing plants and the variation in antibiotic concentrations was determined. Three different antibiotics, chlortetracycline (CTC), sulfamethazine (SMZ), and tylosin (TYL) at three different concentrations (2, 10, and 20 mg kg⁻¹) were also applied to a mixture of pig manure and sawdust and the mixtures incubated using a laboratory scale composting apparatus to monitor the changes in antibiotic concentrations during composting together with the physicochemical properties of the composts. During composting, in both field and lab-scale investigations, the concentrations of all three different antibiotics declined below the relevant Korean guideline values (0.8 mg kg⁻¹ for tetracyclines, 0.2 mg kg⁻¹ for sulfonamides and 1.0 mg kg⁻¹ for macrolides). The decline of tetracycline and sulfonamide concentrations was highly dependent on the presence of sawdust while there was no influence of sawdust on TYL decline.     

Field testing of conversion of sewage sludge to daily landfill cover material

Solidification of sewage sludge has been actively investigated in Japan and Europe since the 1970s. Most previous studies have focused on only the mechanical aspects of potential alternative cover soil made using sewage. Most solidification processes, however, suffer from severe odor problems because of the high alkalinity of the material. The objectives of this study are to develop a cost-effective solidifying agent for conversion of sewage sludge in order to reduce the odor generation, as an alternative to the conventional cement lime-based solidifying agent, and to demonstrate its applicability in the field experimentally. Field test results showed compressive strength well above the 1.0 kg/cm² criterion for landfill cover soil in Korea. Also, the permeability coefficient was far below the 5 × 10⁻⁵ cm/s design criterion for landfill cover soil. Even in harsh weather conditions, such as in winter and summer, the compressive strength was increased. In addition, the permeability was decreased from 3.45 × 10⁻⁶ cm/s to 4.78 × 10⁻⁷ cm/s, and from 2.27 × 10⁻⁶ cm/s to 3.62 × 10⁻⁷ cm/s, at 7 days after placement in January and August, respectively. It can therefore be postulated that the proposed solidification process is an appropriate alternative for production of daily landfill cover material. Concerning the odor problem, 5 min of mixing of sewage with TS103, one of the proprietary agents used in this work, was sufficient to suppress the concentration of ammonia emitted to below 10 ppm. Considering all of these experimental field test results, it is expected that the proposed method could be a competitive approach for manufacture of alternative landfill cover material.     

Is kin cooperation going on undetected in marine bird colonies?

In multitudinous breeding colonies, kin interactions could go unnoticed because we are unaware of the kinship among adults we observe. Evidence of cooperation and competition between close adult kin in a blue-footed booby colony was sought by analyzing patterns of natal dispersal and proximity of nests. Male and female recruits nested closer to their own natal sites than to their parents’ current sites. Males (only) dispersed less far when both parents were present than when no parent or one parent was present, but not selectively close to fathers versus mothers when these were divorced. Neither parental presence nor parental proximity affected breeding success of recruits of either sex. Although distances between the nests of simultaneously recruiting broodmates were unrelated to their sex, males dispersed 13.1 m less when a sister was present than when a brother was present. Neither sex was affected in its dispersal distance by the presence or hatching order/dominance of a broodmate. Neither sex was affected in its breeding success by the presence versus absence of a broodmate, although female success increased with proximity of their brothers. Parents and sisters may actively or passively help males establish their first territories near their natal sites and nearby brothers may help females in their first breeding attempts; otherwise, boobies do not influence each other’s natal dispersal and first breeding success. It appears that boobies do not nest selectively close to or far from their parents, offspring, or broodmates. Why there is apparently so little cooperation and altruism between close adult relatives in booby colonies is puzzling.     

Community gardens and sustainable land use planning: A case-study of the Alex Wilson community garden

An analytical account of the history and aspirations of the Alex Wilson Community Garden in Toronto provides an ideal opportunity to examine the connections between two typically distinct enterprises: ecological restoration and community gardening. These are both important contemporary ecological movements, but are rarely combined in a single project that demonstrates the principles of sustainable land use and community planning. The garden is named in memory of Alex Wilson, a landscape designer, community activist and writer who worked and lived in Toronto, Canada. During his life, Wilson established a community garden which was eventually replaced by conventional urban development. After his death in 1993, friends and colleagues decided to honour his memory by establishing a permanent community garden in his name. The Alex Wilson Community Garden opened to the public in June 1998. The case-study explores how the garden reflects Wilson's work by linking community gardening and ecological restoration. These features are unified in Wilson's work as a means of nurturing relationships between people, communities and the landscape—relationships that are social, economic and ecological. In his book,The Culture of Nature: North American landscape from Disney to the Exxon Valdez (1991), Wilson argues that “we must build landscapes that heal and empower, that make intelligible our relations with each other and the natural world”. The Alex Wilson Community Garden illustrates in a practical manner the principles espoused by Wilson through its design, planning and functioning. The case-study reports on the innovative approach to landscape design taken in the garden, which reconstructs the natural and cultural history of southern Ontario, featuring lake-shore, agricultural and woodland sections. The garden has been planted exclusively with native plant species, and is expected to have a positive impact on local biodiversity. The planning process which led up to the design of the garden was participatory in nature, encompassing friends and colleagues of Alex Wilson, local residents and city planning officials, and made use of a number of planning tools not usually applied in an urban setting, including the granting of a conservation easement. The garden also addresses emerging issues associated with globalisation and large cities by providing food production opportunities for local residents, including a low-income housing complex and a nearby drop-in centre. Ecological monitoring and assessment of the naturalised area will be carried out by local residents.     

Electrochemical conversion of biomass-derived aldehydes into fine chemicals and hydrogen: A review

Environmental Chemistry Letters - The decrease in fossil fuel usage and the projected 28% increase in the global energy demand by 2040 are calling for advanced methods to convert modern biomass...     

“Life just keeps throwing lemons”: the lived experience of food insecurity among Aboriginal people with disabilities in the West Kimberley

This paper reports findings of a qualitative study conducted in collaboration with Aboriginal people with disabilities and their carers residing in the rural and remote Kimberley region of Western Australia, specifically the impact of chronic food insecurity on their daily lives. Nutritious food is important to maintaining health, particularly for Aboriginal people with disabilities who are at the greatest risk of a range of chronic health conditions, illnesses and secondary disability. In the remote areas of the West Kimberley, the high cost of living, including food expenses and the generally low incomes of residents mean that food insecurity is common. A large portion of the population living in remote and rural areas of the Kimberley is Aboriginal, and chronic illness and disability are twice as likely among this group. Lack of access to nutritious food has a cyclical interaction with disability, resulting in secondary impairments and ill health, which leads to greater economic exclusion and further food insecurity. Participants in this research consistently reported that they coped with food insecurity by fishing and crabbing on their traditional lands, “in country”. This link between land sovereignty, food sovereignty and food security for Aboriginal Australians has echoes with global food sovereignty movements.     

Metagenomic assessment of the microbial diversity in ground pork products from markets in the North Central Region of South Korea

The purpose of this study was to characterize the microbial community in ground pork using molecular approaches. Forty six ground pork products were purchased from local stores in the north central area of South Korea. Aerobic plate counts varied 4.23 ± 5.14 × 10⁵ CFU/g with the range between 5.00 × 10³ and 1.85 × 10⁶ CFU/g for ground pork samples. Four ground meat samples were further processed for metagenomic analysis. Pseudomonas species was the most relative abundant with a wide range occurring (1.72 to 77.7%) as part of the microbial genera in ground pork. Bacteria such as Carnobacterium, Yersinia, Photobacterium were also identified in ground pork. Despite the prominence of certain genera across all samples there was still extensive microbial diversity among ground pork products that originated from different slaughter houses and were processed in different markets. Such diversity indicates that designing interventions to extend shelf life may be hampered by the extensive variability in the microbial consortia associated with pork products. However, this diversity may be useful for developing microbial traceability signatures unique to a slaughter house or a particular market.     

Demonstration of a high throughput on-board hydrogen generation reactor system using aluminum coil as fuel for a vehicle

A novel on-board hydrogen generation concept using Al coil with NaOH was investigated. The reaction rate was successfully controlled by introducing a pumping system for the NaOH solution. The time for the flow to develop fully was mainly dependent on the solution temperature, and the fastest start time recorded was 60 sec at a solution temperature of 70°C. The maximum H₂ generation rate was 200 L min^–1 with a prototype design of the on-board hydrogen generation system 1/8 times the size of a full-size reactor. The H₂ generation process coupled with the solution pumping system was simulated with three-dimensional fluid dynamic software, and the calculated H₂ flow and temperature rise of the system were validated with experimental data.     

Reduction of nitrogen excretion and emission in poultry: A review for organic poultry

Organic poultry is an alternative to conventional poultry which is rapidly developing as a response to customers' demand for better food and a cleaner environment. Although organic poultry manure can partially be utilized by organic horticultural producers, litter accumulation as well as excessive nitrogen still remains a challenge to maintain environment pureness, animal, and human health. Compared to conventional poultry, diet formulation without nitrogen overloading in organic poultry is even more complicated due to specific standards and regulations which limit the application of some supplements and imposes specific criteria to the ingredients in use. This is especially valid for methionine provision which supplementation as a crystalline form is only temporarily allowed. This review is focused on the utilization of various protein sources in the preparation of a diet composed of 100% organic ingredients which meet the avian physiology need for methionine, while avoiding protein overload. The potential to use unconventional protein sources such as invertebrates and microbial proteins to achieve optimal amino acid provision is also discussed.