STREAM TYPES IN THE DES MOINES RIVER BASIN1

Stream tributaries in the Des Moines River basin have been classified according to the glacial terrain through which they flow. Three stream types were categorized as follows: (1) streams that flow entirely on Wisconsin drift, (2) streams that flow entirely on Kansan drift, and (3) streams that have their headwaters located on new drift but have their lower reaches flowing on older drift. Selected channel and valley characteristics were measured and used to verify the stream type classification. Five variables were chosen for use in a multiple linear discriminatory analysis, which is a statistical technique developed for the purpose of classifying observations into one of several categories which have been predetermined. The streams in each group were verified with the exception of three anomalies based on the probability associated with the largest linear discriminant function. The rationale for the three anomalous streams is not easily determined. But, they are considered to be associated with pre-glacial drainage or at least pre-Wisconsin age drainage. Otherwise, the analysis shows that the major channels and valleys in the Des Moines River basin tend to reflect the glaciated upland surface.     

CLIMATOLOGICAL WATERSHED CALIBRATION1

ABSTRACT: This study tests the hypothesis that climatic data can be used to develop a watershed model so that stream flow changes following forest harvest can be determined. Measured independent variables were precipitation, daily maximum and minimum temperature, and concurrent relative humidity. Computed variables were humidity deficit, saturated vapor pressure, and ambient vapor pressure. These climatic variables were combined to compute a monthly evaporation index. Finally, the evaporation index and monthly precipitation were regressed with measured monthly stream flow and the monthly estimates of stream flow were combined for the hydrologic year. A regression of predicted versus measured annual stream flow had a standard error of 1.5 inches (within 6.1 percent of the measured value). When 10, 15, and 20 years of data were used to develop the regression equations, predicted minus measured stream flow for the last 7 years of record (1972–1978) were within 16.8, 11.5, and 9.7 percent of the measured mean, respectively. Although single watershed calibration can be used in special conditions, the paired watershed approach is expected to remain the preferred method for determining the effects of forest management on the water resource.     

Drought planning and water allocation: an assessment of local capacity in Minnesota

Water allocation systems are challenged by hydrologic droughts, which reduce available water supplies and can adversely affect human and environmental systems. To address this problem, drought management mechanisms have been instituted in jurisdictions around the world. Historically, these mechanisms have involved a crisis management or reactive approach. An important trend during the past decade in places such as the United States has been a shift to a more proactive approach, emphasizing drought preparedness and local involvement. Unfortunately, local capacity for drought planning is highly variable, with some local governments and organizations proving to be more capable than others of taking on new responsibilities. This paper reports on a study of drought planning and water allocation in the State of Minnesota. Factors facilitating and constraining local capacity for drought planning were identified using in-depth key informant interviews with state officials and members of two small Minnesota cities, combined with an analysis of pertinent documentation. A key factor contributing to the effectiveness of Minnesota's system is a water allocation system with explicit priorities during shortages, and provisions for restrictions. At the same time, the requirement that water suppliers create Public Water Supply Emergency Conservation Plans (PWSECP) clarifies the roles and responsibilities of key local actors. Unfortunately, the research revealed that mandated PWSECP are not always implemented, and that awareness of drought and drought planning measures in general may be poor at the local level. From the perspective of the two cities evaluated, factors that contributed to local capacity included sound financial and human resources, and (in some cases) effective vertical and horizontal linkages. This analysis of experiences in Minnesota highlights problems that can occur when senior governments establish policy frameworks that increase responsibilities at the local level without also addressing local capacity.     

The Impact of BSE and FMD on Ethics and Democratic Process

The recent crises of BSE and FMD in the United Kingdom have revealed widespread concerns on the part of farmers and consumers about government regulations and handling of animal movements, animal welfare, and food safety. Both crises raised issues of government accountability and the lack of openness in public debate. The issues of democratic process and decision-making were especially strong in relation to the mass slaughter policy of the government to control FMD. This article explores public disquiet about these matters, as expressed through the reports of two public inquiries, and the perceived links between government decision-making and the needs of global agribusiness, to the detriment of family farms and animal welfare. In light of the growing evidence about the environmental and economic costs of agribusiness, the argument is made that strong programs of citizen action, such as the Devon Foot and Mouth Inquiry, that are grounded in an ethical stance on animal welfare can challenge the perspectives of central governments about concepts of cost, efficiency, and safety in agriculture.     

Schedule tightness among tractor-trailer drivers

The extent to which schedules are sufficiently tight to encourage violations of Hours-of-Service Regulations, speed limits, or both was investigated through a survey of over 1,600 tractor-trailer drivers. The focus was on drivers with refrigerated trailers. The results indicate high incidence levels of tight schedules. For example, assuming average speed limits of 65 mph, 24% had violation-inducing schedules with regard to the movement they were making at the time of the interviews. Incorporating information about previous driving, the incidence of violation-inducing schedules rose to 40%. Comparison with an earlier study suggests that, despite increases in speed limits which would tend to loosen schedules, schedules have become tighter over the past decade. The implications of these findings for reforms of Hours-of-Service Regulations are briefly discussed.     

Muscle tetanus and loading condition effects on the elastic and viscous characteristics of the thorax

Thoracic deformation under an applied load is an established indicator of injury risk, but the force required to achieve an injurious level of deformation currently is not understood adequately. This article evaluates how two potentially important factors, loading condition and muscle tensing, affect the structural response of the dynamically loaded thorax. Structural models of two human cadaver thoraxes and two porcine thoraxes were used to quantify the effects. The human cadavers, which represent anthropometric extremes, were subjected to anterior loading from (1) a 5.1-cm-wide belt oriented diagonally (i.e., seatbelt-like loading), (2) a 15.2-cm-diameter rigid hub, and (3) a 20.3-cm-wide belt oriented laterally (i.e., a distributed load). A structural model having the mathematical formulation of a quasilinear viscoelastic material model was used to model the elastic and viscous response, with ramp-hold tests used to determine the model coefficients. The effect of thoracic musculature was assessed using similar ramp-hold tests on the porcine subjects, each with and without forced muscle contraction. Even maximally contracted thoracic musculature is shown to have a minimal effect on the response, with similar elastic and viscous characteristics exhibited by each subject regardless of muscle tone. The elastic response is shown to be approximately a factor of three stiffer for diagonal belt loading and for this distributed loading condition than for the hub loading, indicating that the response is influenced most by the particular anatomical structures that are engaged and, secondarily, by the area of load application. Specifically, shoulder involvement is shown to have a strong influence. The force relaxation is found to be pronounced, but insensitive to the loading condition, with long-time force relaxation coefficients (G( infinity )) in the range of 0.1 to 0.3. The findings of this study provide restraint-specific guidelines for the force-deflection characteristics of both physical and computational thoracic models.     

Pathogen survival in swine manure environments and transmission of human enteric illness--a review

The influence of zoonotic pathogens in animal manure on human health and well-being as a direct or indirect cause of human enteric illness is examined. Available international data are considered, but the study is focused on the developing situation in western Canada, where it is certain there will be further rapid growth in livestock numbers, particularly hogs. Major pathogens considered are Escherichia coli O157:H7, Salmonella, Campylobacter, Yersinia, Cryptosporidium, and Giardia. Canada is now the leading exporter of pork internationally, but recent increases in production contrast with constant domestic levels of pork consumption and declining levels of foodborne illness caused by pork. Effects of increased levels of manure production are not quantifiable in terms of effects on human health. The presence of major pathogens in manure and movement to human food sources and water are considered on the basis of available data. Survival of the organisms in soil, manure, and water indicate significant variability in resistance to environmental challenge that are characteristic of the organisms themselves. Generally, pathogens survived longer in environmental samples at cool temperatures but differences were seen in liquid and solid manure. Based on actual data plus some data extrapolated from cattle manure environments, holding manure at 25 degrees C for 90 d will render it free from the pathogens considered above.     

Spatial variability of soil carbon in forested and cultivated sites: implications for change detection

The potential to sequester atmospheric carbon in agricultural and forest soils to offset greenhouse gas emissions has generated interest in measuring changes in soil carbon resulting from changes in land management. However, inherent spatial variability of soil carbon limits the precision of measurement of changes in soil carbon and hence, the ability to detect changes. We analyzed variability of soil carbon by intensively sampling sites under different land management as a step toward developing efficient soil sampling designs. Sites were tilled cropland and a mixed deciduous forest in Tennessee, and old-growth and second-growth coniferous forest in western Washington, USA. Six soil cores within each of three microplots were taken as an initial sample and an additional six cores were taken to simulate resampling. Soil C variability was greater in Washington than in Tennessee, and greater in less disturbed than in more disturbed sites. Using this protocol, our data suggest that differences on the order of 2.0 Mg C ha(-1) could be detected by collection and analysis of cores from at least five (tilled) or two (forest) microplots in Tennessee. More spatial variability in the forested sites in Washington increased the minimum detectable difference, but these systems, consisting of low C content sandy soil with irregularly distributed pockets of organic C in buried logs, are likely to rank among the most spatially heterogeneous of systems. Our results clearly indicate that consistent intramicroplot differences at all sites will enable detection of much more modest changes if the same microplots are resampled.     

How future trends in societal aging, air bag availability, seat belt use, and fleet composition will affect serious injury risk and occurrence in the United States

The objective of this study was to quantify the importance of societal aging relative to other factors that are known to affect injury risk. An aging population's effect on Maximum Abbreviated Injury Scale (MAIS) 3+ injury trends for passenger car drivers in frontal crashes was projected and compared to the effects of projected changes in fleet composition, changes in seat belt usage, and changes in air bag availability. It was determined that increased frailty due to an aging population will result in 19,816 to 43,568 additional injuries to passenger car drivers in frontal crashes from 1996 to 2012. Aging was shown to have an effect similar to the increased presence of light trucks in the fleet (a cumulative increase of approximately 47,428 injuries). Aging and changing fleet composition were shown to have a smaller effect than the projected increases in seat belt use or air bag availability, though the effect of increased belt use is not much greater than the effect of aging. After 2012, however, air bag availability and seat belt use will plateau, while societal aging will continue.     

Ethical Codes in Humanitarian Emergencies: From Practice to Research?

Notable strides have been made in recent years to develop codes of conduct for humanitarian intervention in conflicts on the part of international NGOs and UN organisations. Yet engagement by the academic and broader research communities with humanitarian crises and ongoing complex political emergencies remains relatively ad hoc and unregulated beyond the basic ethical guidelines and norms developed within universities for research in general, and within the governing and representative bodies of particular academic disciplines. This paper draws on a case study of research on humanitarian assistance to Liberia during that country's civil war from 1989 to 1996. The difficulties faced by humanitarian agencies in Liberia led to the development of two key sets of ethical guidelines for humanitarian intervention: the Joint Policy of Operations (JPO) and Principles and Policies of Humanitarian Operations (PPHO). This paper seeks to address what lessons, if any, these ethical guidelines, together with different experiences of conducting research in war-torn Liberia, can provide in terms of the role of academic researchers--and research itself--in humanitarian crises.