Factors affecting children's participation and amount of labor on family farms

METHOD: A two-stage decision-making model is estimated to explain children's participation and labor supply on family farms using unitary and cooperative bargaining frameworks. RESULTS: Results indicate that parents have different preferences about whether their children work and how much they work. The models incorporate non-economic factors and allow for different stochastic processes in the participation and labor supply decisions. CONCLUSIONS: Concerns about children's social development appear to be crucial in deciding children's labor participation, while the child's economic contribution significantly influences both whether they work and how much they work. Some variables affect the two decisions differently. For instance, the higher the parents' education level, the higher the probability children will work but the fewer hours they will work.     

Consequences of livestock grazing on water quality and Benthic algal biomass in a Canadian natural grassland plateau

The effects of livestock grazing on selected riparian and stream attributes, water chemistry, and algal biomass were investigated over a two-year period using livestock enclosures and by completing stream surveys in the Cypress Hills grassland plateau, Alberta, Canada. Livestock enclosure experiments, partially replicated in three streams, comprised four treatments: (1) early season livestock grazing (June–August), (2) late season livestock grazing (August–September), (3) all season grazing (June–September), and (4) livestock absent controls. Livestock grazing significantly decreased streambank stability, biomass of riparian vegetation, and the extent to which aquatic vegetation covered the stream channels compared with livestock-absent controls. Water quality comparisons indicated significant differences among the four livestock grazing treatments in Battle and Graburn creeks but not in Nine Mile Creek. In Graburn Creek, the concentration of total phosphorus in the all-season livestock grazing treatment was significantly higher than that in the livestock-absent control, and the early season and late season grazing treatments. Concentrations of soluble reactive phosphorus in the all-season livestock grazing treatment also exceeded that in livestock-absent control. In contrast, differences in water quality variables in the remaining 22 comparisons (i.e., 22 of the total 24 comparisons) were minor even when differences were statistically significant. Effects of livestock grazing on algal biomass were variable, and there was no consistent pattern among creeks. At the watershed scale, spatial variation in algal biomass was related (P < 0.05) with concentrations of NO₂ ⁻ + NO₃ ⁻ and soluble reactive phosphorus in two of the four study creeks. Nutrient diffusing substrata experiments showed that algal communities were either nitrogen-limited or not limited by nutrients, depending on stream and season.     

Managing Radioactively Contaminated Land: Implications for Habitat Diversity

Radioactive contamination of agricultural land may necessitate long-term changes in food production systems, through application of selected countermeasures, in order to reduce the accumulation of radionuclides in food. We quantified the impact of selected countermeasures on habitat diversity, using the hypothetical case of two agricultural areas in Finland. The management scenarios studied were conversions from grassland to cereal production and from grassland and crop production to afforestation. The two study sites differed with respect to present agricultural production: one being predominantly cereal production and seminatural grasslands, while the other was dominated by intensive grass and dairy production. Some of the management scenarios are expected to affect landscape structures and habitat diversity. These potential changes were assessed using a spatial pattern analysis program in connection with geographic information systems. The studied landscape changes resulted in a more monotonous landscape structure compared to the present management, by increasing the mean habitat patch size, reducing the total habitat edge length and reducing the overall habitat diversity calculated by the Shannon diversity index. The degree of change was dependent on the present agricultural management practice in the case study sites. Where dairy production was predominant, the landscape structure changes were mostly due to conversion of intensive pastures and grasslands to cereal production. In the area dominated by cereal production and seminatural grasslands, the greatest predicted impacts resulted from afforestation of meadows and pastures. The studied management changes are predicted to reduce biodiversity at the species level as well as diminishing species-rich habitats. This study has predicted prominent side effects in habitat diversity resulting from application of management scenarios. These potential long-term impacts should be considered by decision-makers when planning future strategies in the event of radionuclide deposition.     

Comparative Analysis of New Zealand and US Approaches for Agricultural Nonpoint Source Pollution Management

The role of the central government in New Zealand is generally limited to research and policy development, and regional councils are responsible for most monitoring and management of the problem. The role of the federal government in the United States includes research and monitoring, policy development, and regulation. States also have a significant management role. Both countries rely on voluntary approaches for NPS pollution management. Very few national water quality standards exist in New Zealand, whereas standards are widely used in the United States. Loading estimates and modeling are often used in the United States, but not in New Zealand. A wide range of best management practices (BMPs) are used in the United States, including buffer strips and constructed/engineered wetlands. Buffer strips and riparian management have been emphasized and used widely in New Zealand. Many approaches are common to both countries, but management of the problem has only been partly successful. The primary barriers are the inadequacy of the voluntary approach and the lack of scientific tools that are useful to decision-makers. More work needs to be performed on the evaluation of approaches developed in both countries that could be applied in the other countries. In addition, more cooperation and information/technology transfer between the two countries should be encouraged in the future.     

Developing sustainable practices to adapt to the impacts of climate change: a case study of agricultural systems in eastern England (UK)

The weight of scientific evidence suggests that human activities are noticeably influencing the world's climate. However, the effects of global climate change will be unevenly spread, due to local variations in vulnerability and adaptive capacity. Using downscaled projections of future UK climates over the next 50 years, this paper investigates the impacts of, and possible responses to, climate change in one small area in eastern England, selected as a test-bed for sustainable agriculture. It shows that local agricultural systems are vulnerable to changes in the climate. At present, however, these considerations have a limited effect on agricultural operations, which are mainly driven by short-term events and 'non-climate' policies, such as agricultural price support. The capacity of agricultural systems to adapt successfully to climate change will be determined by the ability of producers to integrate climate change into their planning strategies with a view to ultimately ensuring sustainable agricultural practices in the long term. Electronic Publication     

晋冀鲁豫地区的干旱及干旱对农业影响的研究

本文分析了晋冀鲁豫地区近500年来的干旱和干旱对农业的影响,讨论了农业抗旱对策制定所需考虑的降水指标。     

The use and effectiveness of the site of special scientific interest designation in the east midlands region of the nature conservancy council

This paper looks at the use and effectiveness of the Site of Special Scientific Interest designation in three counties in the East Midlands region of the Nature Conservancy Council, namely Nottinghamshire, Northamptonshire and Cambridgeshire. Using unpublished sources within the NCC an analysis is made of the SSSI system in practice since its inception in 1949. A number of findings relating to weaknesses in the designation and the operation of the designation system emerge. Each of these findings is discussed in turn with the presentation of the appropriate evidence from the county case studies.     

沈阳市“十一五”期间的农村农业环境保护对策

根据沈阳市农村农业面临的环境问题,确定“十一五”期间农村农业环境保护目标、指标,提出改善农村农业环境质量的对策措施,保证沈阳市农村农业环境质量的持续改善。     

Lessons learnt from a participatory integrated assessment of greenhouse gas emission reduction options in firms

This article discusses an approach for identification and evaluation of short-term greenhouse gas (GHG) emission reduction options in firms. The approach is based on lessons learnt from a project using Participatory Integrated Assessment (PIA) and builds on the idea that effective public climate policy for firms requires options that have support from stakeholders and are practically feasible. Scenarios are used to provide a link with short-term policy developments and a model assists to communicate quantitative effects of options to participating stakeholders. Our approach can be seen as a first step towards a framework that meets the need for more systematic approaches to PIAs identifying effective public policies for short-term GHG emission reduction options in firms. In order to identify effective options for non-carbon dioxide GHG emission reductions, our approach has been applied to Dutch dairy farms, after which it has been refined. The case study suggests that our approach can provide balance between practical, context specific issues and scientific-theoretical aspects, thereby avoiding common pitfalls of participatory research projects to focus too much on either theory or practical issues.

Stream-bed phosphorus in paired catchments with different agricultural land use intensity

Stream-bed sediments from three paired catchments, each draining a lower agricultural intensity system and a higher agricultural intensity system, were analysed for (a) total P (TP), (b) bioavailable-P (Resin-P), (c) equilibrium phosphorus concentration (EPC₀), and (d) degree of phosphorus saturation (DPS). The influence of agriculture on sediment P was explored within the context of other key variables that may control the sediment P concentrations such as particle size, Fe, Ca and organic matter content, and in terms of potential implications of sediment P to in-stream biota. TP concentrations, EPC₀, and the proportion of fine sediment were highest at the sites with the greater agricultural impact. Higher concentrations of bioavailable-P were also found in higher intensity agricultural systems. However, the highest concentrations of bioavailable-P were found at sites with point source inputs. Sites with high Fe concentrations had higher TP concentrations relative to agricultural intensity, but also had lower DPS values, illustrating that the sediment still had the capacity to take up P in a strongly bound form. The results from this study show that higher risk agricultural practices (intensive arable production and dairy and beef production) can lead either directly, or indirectly through increased inputs of fine sediment, to increased sediment TP concentrations. The importance of geochemical and physical controls on the bed sediments’ capacity to mitigate high P inputs in headwater lowland streams, especially under low flows and times of eutrophication risk in spring and summer is illustrated.