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Carla Roncoli Benjamin S. Orlove Merit R. Kabugo Milton M. Waiswa 《Agriculture and Human Values》2011,28(1):123-138
Climate change is confronting African farmers with growing uncertainties. Advances in seasonal climate predictions offer potential
for assisting farmers in dealing with climate risk. Experimental cases of forecast dissemination to African rural communities
suggest that participatory approaches can facilitate understanding and use of uncertain climate information. But few of these
studies integrate critical reflections on participation that have emerged in the last decade which reveal how participatory
approaches can miss social dynamics of power at the community level and in the broader context. Furthermore, neither climate
application research nor theoretical critiques of participation fully examine the culturally constructed nature of participation.
Drawing on sociolinguistic analysis, in-depth interviews, and ethnographic observation, this paper examines how Ugandan farmers
engage in participation in the context of discussions of seasonal climate forecasts. Forecasts were presented to farmers groups
whose members were then asked to discuss the forecast among themselves. In doing so, groups sought to develop a common understanding
of the forecast and consensual plans for response strategies. Focusing on one particular group meeting as an example, we show
how different cultural styles of participation affect the interpretation of the forecast and the formulation of response strategies.
Group interaction is shown to be mostly structured around two styles of participation. On the one hand, there is the “Western”
style advocated by NGOs and the government, which centers on ensuring that all individuals who are present have opportunities
to speak during discussion and to vote on group decisions. On the other hand, a “Kiganda” style of participation emphasizes
the importance of affirming ties to a collectivity, respect for social hierarchy, deployment of good manners, and consensus
building. The case study illuminates how the performance of different styles of participation is grounded in localized frameworks
of language and culture but also draw on political and policy discourses at the national level. Although a cultural high value
on consensus may work in favor of prominent members, the availability of multiple styles of participation also enables group
members to exercise their agency in positive ways. Attention to the interplay of different styles of participation throws
light on the subtle social processes that shape how knowledge is assessed, which sources are trusted, which and whose interpretations
prevail, what options are deemed viable, how costs and benefits are calculated, and whose resources are mobilized in the effort
to reduce vulnerability to climate risk. These are key questions for an assessment of the role of boundary organizations,
such as farmer associations, in the communication and application of climate forecasts in agriculture. 相似文献
2.
Merit Meier Regula Bettschart-Wolfensberger Colin Claudio Schwarzwald Karine Portier Annette Gysler Simone Katja Ringer 《Journal of veterinary pharmacology and therapeutics》2020,43(5):470-476
Dobutamine is routinely used to improve cardiovascular function in anaesthetized horses. However, dobutamine in conscious horses is insufficiently investigated. Ten research horses that were already instrumented for a preceding trial were included into the study. Cardiovascular variables were recorded and blood samples taken after instrumentation (Baseline), before starting dobutamine and after 10 min of dobutamine infusion (2 µg kg−1 min−1). A significant increase in systemic blood pressure, mean pulmonary artery pressure and right atrial pressure, and a decrease in heart rate were observed with dobutamine compared with baseline measurements. Arterial and mixed venous haemoglobin and oxygen content, as well as mixed venous partial pressure of oxygen increased. No significant changes in cardiac output, stroke volume, systemic vascular resistance, arterial partial pressure of oxygen, or oxygen consumption, delivery and extraction ratio were detected. Concluding, dobutamine increased systemic blood pressure without detectable changes in stroke volume, cardiac output or systemic vascular resistance in conscious horses. 相似文献
3.
The effect of land use type on the dynamics and annual rate of net nitrogen mineralization (NNM) in a naturally generated silver birch stand and in a grassland, both on abandoned agricultural land, was assessed in situ in the upper 0–20 cm soil layer using the method of buried polyethylene bags. Annual NNM rate in the birch stand (156 kg N ha−1 year−1) was higher than in the grassland (102 kg N ha−1 year−1); in both cases NNM covered a major part of the plants annual nitrogen demand. The rate of NNM in the upper 0–10 cm soil layer in the birch stand (99 kg N ha−1 year−1) exceeded the respective rate of NNM in the grassland (51 kg N ha−1 year−1) roughly two times. In the grassland the rates of NNM in the 0–10 and 10–20 cm layers were equal; in the birch stand NNM in the 0–10 cm layer was 1.7 times higher than in deeper 10–20 cm layer. The intensity of daily NNM in the upper 0–10 cm soil layer in the birch stand was the highest in June and in the grassland in May, 776 and 528 mg kg−1 N day−1, respectively. In our study no significant correlation was found between NNM and the environmental factors monthly mean soil temperature, soil moisture content and pH. 相似文献
4.
Merit Kund Aivo Vares Allan Sims Hardi Tullus Veiko Uri 《European Journal of Forest Research》2010,129(4):679-688
Eight-year-old plantations (11) of silver birch were studied on abandoned agricultural land in Estonia. Trees were planted
on uncovered soil and on polyethylene. After eight growing seasons, the height and diameter at breast height of the trees
grown on polyethylene were significantly (P < 0.001) larger than corresponding parameters of the trees grown on uncovered soil. The annual height increment of the birches
grown on the polyethylene was significantly (P < 0.05) larger during six growing seasons after planting compared to that of the trees grown on uncovered soil. However,
annual height increments were not significantly different in the 7th and the 8th growing seasons. The use of polyethylene
mulching had a statistically significant effect (P < 0.001) on the height of the beginning of the live crown in 8-year-old plantations. The differences between the values of
live crown ratio of the trees grown on polyethylene and the values of live crown ratio of the trees grown on uncovered soil
decreased during six growing seasons. However, by the 7th and 8th growing seasons, there was no significant difference (P > 0.05) between the values of the live crown ratio. The height growth of silver birch grown without mulching as well as with
mulching was found to be more intensive on Glossic Podzoluvisol, Calcaric Cambisol, Calcaric Luvisol and Dystric Gleysol; however, the height growth was more intensive on mulched soil. The height growth of the birches was modelled on the single-tree
and stand levels for five soil types. 相似文献
5.
Veiko Uri Krista Lõhmus Ivika Ostonen Hardi Tullus Renal Lastik Merit Vildo 《European Journal of Forest Research》2007,126(4):495-506
The above-ground biomass and production, below-ground biomass, nutrient (NPK) accumulation, fine roots and foliar characteristics
of a 8-year-old silver birch (Betula pendula) natural stand, growing on abandoned agricultural land in Estonia, were investigated. Total above-ground biomass and current
annual production after eight growing seasons was 31.2 and 11.9 t DM ha−1, respectively. The production of stems accounted for 62.4% and below-ground biomass accounted for 19.2% of the total biomass
of the stand. Carbon sequestration in tree biomass reaches roughly 17.5 t C ha−1 during the first 8 years. The biomass of the fine roots (d < 2 mm) was 1.7 ± 0.2 t DM ha−1 and 76.2% of it was located in the 20 cm topsoil layer. The leaf area index (LAI) of the birch stand was estimated as 3.7 m2 m−2 and specific leaf area (SLA) 15.0 ± 0.1 m2 kg−1. The impact of the crown layer on SLA was significant as the leaves are markedly thicker in the upper part of the crown compared
with the lower part. The short-root specific area (SRA) in the 30 cm topsoil was 182.9 ± 9.5 m2 kg−1, specific root length (SRL), root tissue density (RTD) and the number of short-root tips (>95% ectomycorrhizal) per dry mass
unit of short roots were 145.3 ± 8.6 m g−1, 58.6 ± 3.0 kg m−3 and 103.7 ± 5.5 tips mg−1, respectively. In August the amount of nitrogen, phosphorus and potassium, accumulated in above ground biomass, was 192.6,
25.0 and 56.6 kg ha−1, respectively. The annual flux of N and P retranslocation from the leaves to the other tree parts was 57.2 and 3.7 kg ha−1 yr−1 (55 and 27%), respectively, of which 29.1 kg ha−1 N and 2.8 kg ha−1 P were accumulated in the above-ground part of the stand. 相似文献
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