AGROFORESTRY ADDRESSING SOCIAL AND ENVIRONMENTAL ISSUES IN PARAGUAY

Paraguay is characterized in part by an economy reliant on a massive soy industry and as facing social and economic challenges resulting from highly inequitable distribution of wealth and land ownership, particularly for smallholder farmers in the rural areas of the country. Yerba mate (Ilex paraguariensis), a native tree of which the leaves are used in tea, has become an increasingly common crop grown among common among smallholder farmers (owners of 10 hectares or less) as a viable alternative to soy production on a small scale. In the rural agricultural community of Libertad del Sur, located in the heart of the severely deforested Bosque Atlántico del Alto-Paraná, a series of development initiatives including tree nurseries and agroforestry projects with yerba mate were implemented with involvement of several governmental and nongovernmental organizations. Research was conducted to identify effectiveness of an agroforestry strategy to promote reforestation activities and sustainable agriculture to achieve economic and subsistence goals of the rural population. Despite a severe drought impacting initial research goals, important lessons are considered regarding promotion of development work within the community as well as community perceptions towards development agencies. Pursuit of compromise between community member and agency goals using sustainable agricultural practices is identified as an effective means to promote mutually beneficial development strategies

Influence of Algae on Soil Saturated Hydraulic Conductivity: An \u3ci\u3ein situ\u3c/i\u3e Treatment Option for Reducing Infiltration Beneath Unlined Algae Cultivation Ponds

Commercial production of algal biofuels is currently limited by high capital costs, including the cost of installation and maintenance of plastic pond liners, which mitigate seepage of cultivation fluids and control the release of salts and nutrients into the subsurface beneath outdoor algae cultivation ponds. However, studies of animal waste settling lagoons show that underlying soils ranging from sands to clay loams can exhibit reduced hydraulic conductivity within days to weeks after construction, reducing the need for plastic liners. The mechanisms of the hydraulic conductivity reductions, or “soil sealing”, are physical rearrangement of soil particles, buildup of fines, and the accumulation of microorganisms and their metabolic products within pore spaces. metabolic products within pore spaces. In this study, laboratory-scale soil column experiments investigated a new application for old technology by using fluids that are low-cost and readily available in algae biofuel production to reduce the saturated hydraulic conductivity (Ks) of soils of varying textures by promoting physical and microbial pore clogging mechanisms. Three fluid treatments were supplied to a fine sand soil 1) a nutrient solution used in commercial algae cultivation (NS), 2) the nutrient solution with glycerol added (NSG) and 3) algae (Scenedesmus dimorphus) growing in the nutrient solution (NSA). Relatively small reductions of Ks by NS (44-63%) indicate that the culture broth alone was insufficient to promote soil clogging. Larger reductions (77-94%) were seen by addition of the carbon substrate glycerol to the nutrient solution, indicative of enhanced bacterial growth. However, the Ks values produced by the NSG varied widely over time. The magnitudes of Ks reductions by NSA were also large (84-95%) and remained stable. The large, stable Ks reductions provided by algae, seen in the fine sand soil, were similar to those for a loamy sand (96-99%) and a loam soil (98%). The approximately two-order-of-magnitude Ks reductions imply that, like organic fines in animal waste holding ponds, algae can also significantly contribute to reductions in Ks of soils. This new technology appears to be successful in reducing the Ks of native soils and suggests the technology could be applied as an alternative to plastic liners

Seasonal variation in sea level in the Pacific Ocean during the International Geophysical Year, 1957-1958

Seasonal variations in sea level derived from IGY measurements are described and compared with those previously published. These measurements confirm the earlier descriptions, which were baaed on observations from gauges attached mostly to continental coastlines. That is, in low latitudes in each hemisphere, sea level is high at the end of summer. There is a zonal band of high sea level from about the Equator to 40° N in September while in comparable southern latitudes sea level is low...

Ocean currents above the continental shelf off Oregon as measured with a single array of current meters

Ocean currents were measured with meters moored above the Oregon continental shelf during four periods of about 25 days each----in July, September, and October 1965 and in February 1966. The data are described with histograms and progressive vector diagrams. Velocity variations having a frequency lower than one cycle in two days were associated with similar variations in wind in the alongshore direction...

Prevention of Hepatitis B reactivation in the setting of immunosuppression

Advances in the treatment of malignant and inflammatory diseases have developed over time, with increasing use of chemotherapeutic and immunosuppressive agents of a range of drug classes with varying mechanism and potency in their effects on the immune system. These advances have been met with the challenge of increased risk of hepatitis B virus (HBV) reactivation in susceptible individuals. The magnitude of risk of HBV reactivation is associated with the individual’s HBV serological status and the potency and duration of immunosuppression. Individuals with chronic hepatitis B (CHB) and previously infected but serologically cleared HBV infection are both susceptible to HBV reactivation. HBV reactivation in the setting of immunosuppression is a potentially life threatening condition leading to liver failure and death in extreme cases. It is important to recognize that HBV reactivation in the setting of immunosuppression is potentially preventable. Therefore, identification of patients at risk of HBV reactivation and institution of prophylactic antiviral therapy prior to initiation of immunosuppression is essential

The seasonal oscillation in sea level

On the basis of all available tide gauge records, bathythermograma, and Nansen bottle casts, we have compiled, on a global scale, monthly departures of recorded and steric sea levels from their annual means. The steric fluctuation is defined in terms of the seasonal fluctuation in specific volume. The results are given in the appendices and in three charts, together with error estimates. In general, the departures are comfortably above the uncertainties introduced by year to year variations and by the effects of local topography...

Poor Perception of Body Weight Category amongst the Overweight and Obese with Chronic Hepatitis C: A Target for Intervention

Obesity in chronic hepatitis C (CHC) is associated with adverse hepatic and metabolic outcomes. This prospective study evaluates the agreement between self-perceived body weight (BW) status and measured body mass index (BMI) category and factors associated with its underestimation in CHC. Body size perception was measured with the Contour Drawing Rating Scale. Two hundred and seventy-three patients with CHC (overweight 45%, obese 18%) participated in this study. Although both overweight and obese demonstrated good body size perception, agreement between perceived BW and measured BMI categories was poor (κ = 0.315, 95% CI 0.231–0.399); 33% of overweight/obese respondents considered themselves normal or underweight. Male gender (OR 2.84) and overweight (OR 2.42) or obese BMI (OR 14.19) were associated with underestimation of BW category. Targeted interventions are needed to improve body weight perception, thereby enhancing the uptake of health advice on management of excess body weight in CHC

Present research, facilities and staff

This report summarizes the present status of research work at the Depart­ment of Oceanography, Oregon State College, under Contract Nonr 1286(02) Project NR 083-102 with the Office of Naval Research. After this date quarterly progress reports will be submitted

Research activities during the period 1 January through 31 March 1961

This report summarizes the research conducted during the first quarter of the calendar year 1961 by the Department of Oceanography, Oregon State University, under Contract Nonr 1286(02) Project NR 083-102 with the Office of Naval Research