2,573 research outputs found
Survey among Belgian pig producers about the introduction of group housing systems for gestating sows
There is a global move from individual to group housing of gestating sows. In the European Union, individual gestating stalls will be banned by 2013. Just like in other industrialized regions, these stalls have been the standard housing system for intensively kept sows from the 1960s onward in the Flemish region of Belgium. Because the socioeconomic consequences for the pig industry may be far-reaching and because farmer attitude may influence the realization of the hoped-for improvement in animal welfare in practice, we conducted a survey from 2003 until 2009 among representative samples of Flemish pig producers every 2 yr. The share of farms with group housing increased from 10.5% in 2003 to 29.8% in 2007, but then dropped to 24.6% in 2009. It appears that after 2005 users of old group housing systems in particular stopped farming. Because sow herd size increased more on farms with vs. without group housing and because the proportion of the herd that was group-housed also tended to increase between 2003 to 2009, the change to group housing took place faster when expressed at the level of the sow (from 9.1% in 2003 to 34.1% in 2009) instead of farm. The percentage of farmers planning to convert to group housing within 2 yr was 4.1% in 2003, and 6 to 7% thereafter. These were typically young farmers (P = 0.006) with a large sow herd (P < 0.001) and with a likely successor (P = 0.03). Free access stalls were the most common group housing system (31% of farms, 37% of sows). Their popularity is expected to increase further at the expense of electronic feeding stations, ad libitum feeding, and stalls/troughs with manual feed delivery. User satisfaction was generally high but depended on whether or not all gestating sows were kept in group (P < 0.001), the provisioning of environmental enrichment (P = 0.057), and the age (P = 0.012) and type (P = 0.016) of system. The main criteria for choosing a certain group housing system were the investment costs and sow health and welfare. The importance of economic reasons (P = 0.007) and type of labor (P = 0.043) decreased with the age of the system. In 2003 and 2005 the main reason for not having converted to group housing was that farmers would stop keeping sows by 2013. In 2007 and 2009 the reasons mainly concerned uncertainty about the future and maximally delaying the conversion. Belgium is one of the European Union countries where the pig industry is expected to undergo drastic changes during the few years remaining before the ban on individual housing
Integrated Pest Management on Rangeland: State of the Art in the Sagebrush Ecosystem
Several sagebrush communities represent optimum levels of negative development plant productivity for certain peculiar sites, and therefore should be managed for their preservation. Other sagebrush communities may be profitably modified to favor forage species that are more palatable to domestic livestock. Modification techniques can range from subtle (i.e., grazing strategies) to tracematic (i.e., brush removal and revegetation), and an associated spectrum of management tactics are described. Interrelationships between and problems associated with management of forage resources, management of weeds, and management of insects (including grasshoppers, black grass bugs, and beneficial insects) are discussed. Economical analyses, the role of modeling as a management tool, and impacts of management tactics on wildlife and non-target species also are discussed
Comparison of soil properties measurements in pipeline corrosion estimation
Soil corrosion is a hazardous electrochemical process that affects buried metals in contact with soil. Corrosion in soils resembles atmospheric corrosion with corrosion rates usually higher and depending on the soil type. There are numerous properties of soil and thus soils can be classified in many different ways. Soil resistivity is one of the main indicators of soil corrosivity and thus of the hazardous impact the soil has on metal materials in soil environment, although it is not the only parameter affecting the risk of corrosion damage. In this work on-site measurements and laboratory measurements of soil characteristics are performed and compared. On- site measurements include measuring the redox potential and soil resistivity by Wenner 4-pin method, while the measurements in laboratory include measuring soil conductivity, as well as moisture content, pH, content of sulphates, chlorides and sulfides and polarization measurements, which give the most accurate results. The measurements have shown that if the Wenner 4- pin method is performed in a convenient way the obtained results are not precise but can give an indicative picture of the corrosivity of the observed soil
Epidemic Spruce Beetle Outbreak Changes Drivers of Engelmann Spruce Regeneration
Climateāmediated disturbances outside the range of historical variability can have severe consequences on vital, postādisturbance regeneration processes. Highāelevation forests of the Rocky Mountains that are dominated by Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) are expected to be sensitive to climate change. Additionally, these forests have experienced recent epidemic spruce beetle (Dendroctonus rufipennis) outbreaks that have often resulted in \u3e95% mortality of overstory Engelmann spruce. Therefore, the future distribution of Engelmann spruce forests depends largely on natural regeneration processes. We examined Engelmann spruce seedlings across gradients in soil moisture and stand structural conditions 20 yr postādisturbance on the Markagunt Plateau in southern Utah. All Engelmann spruce seedlings were mapped, measured, and aged, and aspects of stand structure and the microclimate were measured. The goal of our research was to infer processes affecting Engelmann spruce establishment by determining if patterns of advance regeneration that established before the outbreak (~60% of individuals) differed from seedlings that established during and immediately following the outbreak (combined into one group, ~40% of individuals). A generalized linear multiāmodel approach identified that the density of advance regeneration (seedlings/saplings) was negatively influenced by historical competition with overstory trees. In contrast, postāoutbreak regeneration was related to microclimate conditions, including positive relationships with climatic moisture deficit and July soil water content. All seedlings were not significantly clustered around Engelmann spruce snags; however, there was evidence of facilitation of postāoutbreak seedlings by preāoutbreak seedlings at higher elevation sites with lower moisture deficit. Together, these findings suggest postāoutbreak seedlings were not moistureālimited at lower elevations but instead encouraged by higher evapotranspiration. Moreover, facilitation at higher elevations likely resulted from how preāoutbreak seedlings modify snowpack and associated seedbed environments. Our study provides insight for managing Engelmann spruce after a beetle outbreak. In these forests, preā and postāoutbreak regeneration can increase resilience to climateādisturbance interactions, but are patchy and structured at different scales. Therefore, the presence of advance regeneration and the likelihood of postāoutbreak seedlings depend on local environment (soil moisture and stand structure) and could be taken into account to most effectively plan postādisturbance planting activities
Big Sagebrush Response to One-Way and Two-Way Chaining in Southeastern Utah
A decadent, mixed stand of Wyoming big sagebrush, Artemisia tridentata wyomingensis, and mountain big sagebrush, Artemisia tridentata vaseyana, located north of Cisco, Utah, was subjected to one-way and two-way chaining treatments in November 1987. The effect of the treatments on plant community characteristics and shrub vigor was documented over a 3-year period. Stand density was reduced 60 percent on sites chained two ways and 43 percent on sites chained over once. Shrubs on one-way chained sites produced more leader growth in 1989 and 1990 than those on untreated sites or sites chained two ways. Browse production on one-way chained sites surpassed that of untreated sites and two-way chained sites by 140 percent and 350 percent, respectively. Over the short term, a one-way chaining was shown to be an effective method for improving sagebrush vigor and production on a critical mule deer winter range
Assessing Interconnections Between Wilderness and Adjacent Lands: The Grand Staircase-Escalante National Monument, Utah
Wilderness managers have traditionally managed wilderness lands based on the ecological and social content of wilderness areas. The authors propose a framework to systematically account for the biophysical, socioeconomic, and wildness characteristics of the broader landscape context. The method was applied to the proposed wilderness lands of the Grand Staircase-Escalante National Monument in southern Utah. The results illustrate patterns of interdependencies across the landscape. Spatial data demonstrate links between the integrity of proposed wilderness lands and the management of adjacent land units, and links between the economic health of local communities and the management of proposed wilderness and adjacent federal lands
Fungicide, Insecticide, and Foliar Fertilizer Effect on Soybean Yield, Seed Composition, and Canopy Retention
Soybean [Glycine max (L.) Merr.] yield has increased over time through the introduction of new varieties and improved agronomic practices. However, seed protein concentration has decreased. We conducted field studies in 2018 and 2019 to investigate the effects of fungicide, insecticide, and foliar fertilizer application on grain yield and seed quality in two soybean maturity groups (MG). Ināseason treatments targeted nutrient availability and soybean canopy duration during the seedāfilling period by fungicide, insecticide, or foliar fertilizer application at the onset of this period. Biomass samples were collected at R5, R6, and R7 and partitioned into plant parts. Year, location, and MG often influenced yield and seed composition, but foliar fungicide, insecticide, or fertilizer application had no impact on these parameters
Assessment the flood hazard arising from land use change in a forested catchment in northern Iran
The provinces of northern Iran that border the Caspian Sea are forested and may be prone to increased risks of flooding due to deforestation and other land use changes, in addition to climate change effects. This research investigated changes in runoff from a small forested catchment in northern Iran for several land use change scenarios and the effects of higher rainfall and high antecedent soil moisture. Peak discharges and total runoff volumes from the catchment were estimated using the US Soil Conservation Service 'Curve Number' (SCS-CN) method and the SCS dimensionless unit hydrograph. This method was selected for reasons of data availability and operational simplicity for flood managers. A GIS was used to manipulate spatial data for use in the catchment runoff modelling. The results show that runoff is predicted to increase as a result of deforestation, which is dependent on the proportion of the catchment area affected. However, climate change presents a significant flood hazard even in the absence of deforestation. Other land use changes may reduce the peak discharges of all return period floods. Therefore a future ban on timber extraction, combined with agricultural utilisation of rangeland, could prove effective as 'nature-based' flood reduction measures throughout northern Iran
Risk of Childhood Cancers Associated with Residence in Agriculturally Intense Areas in the United States
Background: The potential for widespread exposure to agricultural pesticides through drift during application raises concerns about possible health effects to exposed children living in areas of high agricultural activity.
Objectives: We evaluated whether residence in a county with greater agricultural activity was associated with risk of developing cancer in children \u3c 15 years of age.
Methods: Incidence data for U.S. children 0ā14 years of age diagnosed with cancer between 1995 and 2001 were provided by member registries of the North American Association of Central Cancer Registries. We determined percent cropland for each county using agricultural census data, and used the overall study distribution to classify agriculturally intense counties. We estimated odds ratios and 95% confidence intervals for all ages and 5-year age groups for total cancers and selected cancer sites using logistic regression.
Results: Our study results showed statistically significant increased risk estimates for many types of childhood cancers associated with residence at diagnosis in counties having a moderate to high level of agricultural activity, with a remarkably consistent doseāresponse effect seen for counties having ā„ 60% of the total county acreage devoted to farming. Risk for different cancers varied by type of crop.
Conclusions: Although interpretation is limited by the ecologic design, in this study we were able to evaluate rarer childhood cancers across a diverse agricultural topography. The findings of this exploratory study support a continued interest in the possible impact of long-term, low-level pesticide exposure in communities located in agriculturally intense areas
Demystifying Governance and its Role for Transitions in Urban SocialāEcological Systems
Governance is key to sustainable urban transitions. Governance is a system of social, power, and decisionāmaking processes that acts as a key driver of resource allocation and use, yet ecologistsāeven urban ecologistsāseldom consider governance concepts in their work. Transitions to more sustainable futures are becoming increasingly important to the management of many ecosystems and landscapes, and particularly so for urban systems. We briefly identify and synthesize important governance dimensions of urban sustainability transitions, using illustrations from cities in which longāterm socialāecological governance research is underway. This article concludes with a call to ecologists who are interested in environmental stewardship, and to urban ecologists in particular, to consider the role of governance as a driver in the dynamics of the systems they study
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