Prevention strategies for field traffic-induced subsoil compaction: a review: Part 2. Equipment and field practices

The loads imposed by modern farm machinery have considerable potential to increase subsoil stress. Within the context of economically viable and environmentally sustainable systems, the practices associated with subsoil damage and methods for avoidance are identified. The greatest potential for damage is on fragile, wet or loosened subsoils combined with high wheel or track loads and contact pressures that create noticeable ruts in the topsoil. In-furrow ploughing increases this potential considerably by placing loads on the subsoil. Measures to avoid this potential involve a whole farm approach and an understanding of the many interactions between cropping systems and machinery. Alternatives to in-furrow ploughing that involve working from the surface and building a protective topsoil are discussed. Key measures to reduce the risk to subsoils involve a clear understanding of tyre load and inflation data and simple on-farm methods of achieving this are suggested. Although avoidance has the potential to reduce the risk, confinement of damage to specific strips in the field is seen as a realistic alternative. Controlled traffic operations, together with precision guidance, offer an economic means by which compaction on the cropped area can be avoided. The most effective route to improvement in soil care across the European Union (EU) is an appropriate management structure coupled with a best practice framework.     

Phytate, calcium, iron, and zinc contents and their molar ratios in foods commonly consumed in China

A total of 60 food samples commonly consumed in China were analyzed for phytate using the anion-exchange method and for calcium, iron, and zinc using atomic absorption spectrophotometry. The foods analyzed included those based on cereal grains and soybean. Phytate contents expressed on a wet weight basis ranged from 0 for foods made from starches to 1878 mg/100 g for dried stick-shaped soybean milk film. The calcium contents were between 2.08 mg/100 g for ground corn and 760.67 mg/100 g for diced fried soybean curd. The lowest values of iron and zinc were 0.04 mg/100 g for Panjin pearl rice cooked with discarding extra water and 0.08 mg/100 g for potato and bean starches, while the highest values of iron and zinc were observed in dried stick-shaped soybean milk film. Although many foods were relatively rich in calcium, zinc, and iron, many also contained a higher level of phytate. Of the 60 food samples, 34 foods had a phytate/calcium molar ratio >0.24, 53 foods had a phytate/iron molar ratio >1, 31 foods had a phytate/zinc molar ratio >15, and only 7 foods had a phytate x calcium/zinc >200. Phytate in foods impair the bioavailability of calcium, iron, and zinc, which to some extent depends upon food processing and cooking methods.     

Extracting soil microarthropods with olive oil: A novel mechanical extraction method for mesofauna from sandy soils

Many soil ecologists still encounter practical difficulties when extracting microarthropods from the soil. Methods using a humidity gradient, established by the use of a heat source, for collecting soil animals appeared not sufficiently efficient in case of sandy soils. For such type of soils, flotation techniques proved more suitable. The use of toxic or aggressive flotation fluids like kerosene, dibromo ethane, carbon tetrachloride and heptane, however, makes these methods less favourable. To circumvent this problem, a novel technique has been developed based on the flotation principle but using olive oil. The method uses a pumping system that injects olive oil at the base of a Perspex column in which the soil sample is suspended in water using a propeller. In this way, intensive contact between oil droplets and the organisms is established, increasing extraction efficiency. After stopping the propeller, animals can easily be collected from the oil floating to the water surface. Adding coloured mites to soil samples was used to determine extraction efficiency of the method. Average (±SD) recoveries of 82.7 ± 7.4% (n = 34) and 89.7 ± 10.0% (n = 10), respectively were obtained when extracting storage mites and predatory mites from a sandy soil.     

From unplanned to planned agricultural use: making an asset out of wastewater

Urban wastewater is increasingly used for agricultural production, particularly in those areas where access to fresh water resources is limiting. Depending on the prevailing institutional arrangements, this agricultural use is planned or unplanned. If planned, a general policy is to minimise health risks and environmental pollution, leading to an often centralised collection of the city’s sewage, followed by primary, secondary and further treatment until the prevalent discharge effluent use standards are met. If society can afford them, advanced treatment technologies are installed, backed by a well functioning institutional infrastructure. In contrast, in less prosperous countries the agricultural use of wastewater is driven by the high needs for water and the absence of affordable fresh water resources along with insufficient financial means to construct treatment systems and distribution networks that comply with the official regulations. Combined with a poor institutional framework, this results in unplanned and unguided direct or indirect use of raw, partially treated or diluted wastewater. In an effort to mitigate health and environmental problems, we propose using a reverse water chain design approach, in which the ultimate fate of the water is the basis for the design of conveyance and treatment facilities.     

Cerebral Accumulation of Dietary Derivable Plant Sterols does not Interfere with Memory and Anxiety Related Behavior in Abcg5?/? Mice

Plant sterols such as sitosterol and campesterol are frequently applied as functional food in the prevention of atherosclerosis. Recently, it became clear that plasma derived plant sterols accumulate in murine brains. We questioned whether plant sterols in the brain are associated with alterations in brain cholesterol homeostasis and subsequently with brain functions. ATP binding cassette (Abc)g5-/- mice, a phytosterolemia model, were compared to Abcg5+/+ mice for serum and brain plant sterol accumulation and behavioral and cognitive performance. Serum and brain plant sterol concentrations were respectively 35-70-fold and 5-12-fold increased in Abcg5-/- mice (P<0.001). Plant sterol accumulation resulted in decreased levels of desmosterol (P<0.01) and 24(S)-hydroxycholesterol (P<0.01) in the hippocampus, the brain region important for learning and memory functions, and increased lanosterol levels (P<0.01) in the cortex. However, Abcg5-/- and Abcg5+/+ displayed no differences in memory functions or in anxiety and mood related behavior. The swimming speed of the Abcg5-/- mice was slightly higher compared to Abcg5+/+ mice (P<0.001). In conclusion, plant sterols in the brains of Abcg5-/- mice did have consequences for brain cholesterol metabolism, but did not lead to an overt phenotype of memory or anxiety related behavior. Thus, our data provide no contra-indication for nutritional intake of plant sterol enriched nutrition.     

Factors affecting fish yield and profit in fish pen culture in flooded ricefields

In recent years, a rotational system consisting of two rice crops followed by a fish pen culture during the monsoon flood period was adopted in parts of the flood-prone region of the Mekong Delta. In this paper, we use the survey data from 51 fish pen farmers at Co Do and Vinh Thanh district, Can Tho City, to investigate the factors affecting fish yield and profit in such fish pen culture system. The net yield of all stocked fish varies from 377 to 3,782?kg/ha/crop while the return above variable costs varies from ?5.3 to 9.8 million VND/ha/crop. Low fish price at harvest and the difficulty to sell below market sized fish at a period of oversupply are the main problems for fish pen culture. Fish net yield significantly increases with stocking density and is linked with specific polycultures. Common carp and bighead carp perform best in fish pen culture, both in production and profit considerations. Harvest body mass of common carp is mainly limited by increasing common carp stocking density. Therefore, a stocking density of common carp of about 6,000 fish/ha is recommended to obtain the optimum combination of reasonable body masses, and a good price, as well as a high return above fingerling costs.     

Risk analysis-based food safety policy: scientific factors versus socio-cultural factors

The purpose of this article is to illustrate the importance of socio-cultural factors in risk management and the need to incorporate these factors in a standard, internationally recognized (WTO) framework. This was achieved by analysing the relevance of these factors in three cases. It can be concluded that the pre-eminent role of science in food-related regulatory decisions is debatable. At a risk management level, other factors, such as cultural, social, or economic issues, are often more important than scientific advice in determining policy. There is a need for transparency at an international level as trade barriers are gradually being removed and these other factors are becoming more apparent. Therefore it is important that all the factors implicated in the food safety policy-making process are recognized in a standard framework.     

Risk management in primary apicultural production. Part 2: a Hazard Analysis Critical Control Point approach to assuring the safety of unprocessed honey

In managing risks associated with the human consumption of honey, all sectors of the production chain must be considered, including the primary production phase. Although the introduction of the Hazard Analysis Critical Control Point (HACCP) system has not been made compulsory for purposes of quality and safety control in farming operations, European legislation makes many references to the key role of primary production in food safety management and the HACCP system has been indicated as the preferred tool to ensure that consumers are provided with safe foods. This article describes a systematic HACCP-based approach to identifying, preventing and controlling food safety hazards occurring in primary apicultural production. This approach serves as a useful tool for beekeepers, food business operators, veterinary advisors, and for Food and Veterinary Official Control Bodies in their planning and conducting of audits and for establishing priorities for the evaluation of training programmes in the apicultural sector.