15 research outputs found
Quantifying farmersâ preferences for cropping systems intensification: A choice experiment approach applied in coastal Bangladeshâs risk prone farming systems
Sustainable intensification (SI) is envisioned as an effective strategy for developing countries to increase farm productivity while reducing negative environmental and social externalities. The development of regionally appropriate SI options however requires accounting for the knowledge and preferences of key stakeholders. In Bangladesh, the Government has requested international donors to support the development of dry season rice expansion in the coastal region. Policies however tend to be made without adequate study of farmersâ preferences and ambitions; this can render crop intensification efforts ineffective. Understanding farmersâ preferences for alternative crops and crop management practices are therefore crucial for success where agricultural development investments aim at incorporating the principles of SI.
OBJECTIVE(S): Using coastal Bangladesh as a case studyâ we aim to (1) quantify farmersâ preferences for alternative irrigated crop and crop management options in comparison to the status quo (land fallowing), (2) analyze whether farmersâ preferences are conditioned by concerns regarding the cost and availability of irrigation and fertilizer inputs in comparison to expected net revenues, (3) understand how the heterogeneity in preferences can be attributed to farmer and/or farm characteristics, institutional, and biophysical factors, (4) determine how much farmersâ are willing to invest in different crops and crop management options â including
those reliant and not reliant on irrigation.
METHODS: Taking 300 farmers in two diverse coastal environments, a choice experiment (CE) was employed to explore the heterogeneity in farmersâ preferences for different dry ârabiâ season intensification options (âboroâ rice, maize, wheat and mungbean) against the status quo (dry season land fallowing after harvest of the monsoon season rice crop). Analyses included random parameter logit modeling followed by willingness-to-invest and profit simulations.
RESULTS AND CONCLUSIONS: Analyses revealed strong farmer preferences against rice and in favor of irrigated maize, and also in favor of rainfed or partially irrigated mungbean as an alternative to land fallowing. Irrespective of their location and environmental conditions, respondents had largely a negative preference for irrigation and fertilizer use due to high investment costs and associated production risks in the dry season. Nonetheless, a significant positive effect on their willingness-to-intensify cropping was observed where farmers felt it feasible to provide in-field drainage to limit waterlogging risks.EstaciĂłn Experimental Agropecuaria BarilocheFil: Aravindakshan, Sreejith. Wageningen University and Research. Farming Systems Ecology, ; HolandaFil: Aravindakshan, Sreejith. International Maize and Wheat Improvement Center (CIMMYT); BangladeshFil: Krupnik, Timothy J. International Maize and Wheat Improvement Center (CIMMYT); BangladeshFil: Amjath-Babu, T.S. International Maize and Wheat Improvement Center (CIMMYT); BangladeshFil: Speelman, Stijn. Ghent University. Department of Agricultural Economics; BĂ©lgicaFil: Tur-Cardona, Juan. Ghent University. Department of Agricultural Economics; BĂ©lgicaFil: Tittonell, Pablo Adrian. Instituto Nacional de TecnologĂa Agropecuaria (INTA). EstaciĂłn Experimental Agropecuaria Bariloche; ArgentinaFil: Tittonell, Pablo Adrian. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Investigaciones Forestales y Agropecuarias Bariloche; ArgentinaFil: Tittonell, Pablo Adrian. Groningen University. Groningen Institute of Evolutionary Life Sciences; HolandaFil: Groot, Jeroen C.J. Wageningen University and Research. Farming Systems Ecology; HolandaFil: Groot, Jeroen C.J. Bioversity International; ItaliaFil: Groot, Jeroen C.J. International Maize and Wheat Improvement Center (CIMMYT); Mexic
Predicting the distribution of forest tree species using topographic variables and vegetation index in eastern Acre, Brazil
Species distribution modeling has relevant implications for the studies of biodiversity, decision making about conservation and knowledge about ecological requirements of the species. The aim of this study was to evaluate if the use of forest inventories can improve the estimation of occurrence probability, identify the limits of the potential distribution and habitat preference of a group of timber tree species. The environmental predictor variables were: elevation, slope, aspect, normalized difference vegetation index (NDVI) and height above the nearest drainage (HAND). To estimate the distribution of species we used the maximum entropy method (Maxent). In comparison with a random distribution, using topographic variables and vegetation index as features, the Maxent method predicted with an average accuracy of 86% the geographical distribution of studied species. The altitude and NDVI were the most important variables. There were limitations to the interpolation of the models for non-sampled locations and that are outside of the elevation gradient associated with the occurrence data in approximately 7% of the basin area. Ceiba pentandra (samaúma), Castilla ulei (caucho) and Hura crepitans (assacu) is more likely to occur in nearby water course areas. Clarisia racemosa (guariúba), Amburana acreana (cerejeira), Aspidosperma macrocarpon (pereiro), Apuleia leiocarpa (cumaru cetim), Aspidosperma parvifolium (amarelão) and Astronium lecointei (aroeira) can also occur in upland forest and well drained soils. This modeling approach has potential for application on other tropical species still less studied, especially those that are under pressure from logging
Posaconazole treatment of refractory eumycetoma and chromoblastomycosis Tratamento com posaconazol de casos de cromoblastomicose e micetoma maduromicĂłtico resistentes a outros antifĂșngicos
Eumycetoma and chromoblastomycosis are chronic, disfiguring fungal infections of the subcutaneous tissue that rarely resolve spontaneously. Most patients do not achieve sustained long-term benefits from available treatments; therefore, new therapeutic options are needed. We evaluated the efficacy of posaconazole, a new extended-spectrum triazole antifungal agent, in 12 patients with eumycetoma or chromoblastomycosis refractory to existing antifungal therapies. Posaconazole 800 mg/d was given in divided doses for a maximum of 34 months. Complete or partial clinical response was considered a success; stable disease or failure was considered a nonsuccess. All 12 patients had proven infections refractory to standard therapy. Clinical success was reported for five of six patients with eumycetoma and five of six patients with chromoblastomycosis. Two patients were reported to have stable disease. As part of a treatment-use extension protocol, two patients with eumycetoma who initially had successful outcome were successfully retreated with posaconazole after a treatment hiatus of > 10 months. Posaconazole was well tolerated during long-term administration (up to 1015 d). Posaconazole therapy resulted in successful outcome in most patients with eumycetoma or chromoblastomycosis refractory to standard therapies, suggesting that posaconazole may be an important treatment option for these diseases.<br>Eumicetoma e cromoblastomicose sĂŁo infecçÔes fĂșngicas crĂŽnicas do tecido subcutĂąneo que evoluem com aspecto desfigurado, raramente involuindo espontaneamente. A maioria dos pacientes nĂŁo apresenta melhora sustentada por longo tempo com os tratamentos disponĂveis, sendo de grande importĂąncia as novas opçÔes terapĂȘuticas. A eficĂĄcia do posaconazol, um novo agente antifĂșngico de amplo espectro do grupo dos triazĂłis, foi estudada em 12 pacientes com eumicetoma ou cromoblastomicose refratĂĄria Ă s terapĂȘuticas antifĂșngicas disponĂveis. Os pacientes receberam por no mĂĄximo 34 meses, doses divididas de 800 mg/dia de posaconazol. Resposta clĂnica parcial ou completa foi considerada como sucesso; doença estĂĄvel ou falha terapĂȘutica foi considerada como insucesso. Todos os 12 pacientes tinham infecçÔes comprovadas ou provĂĄveis, refratĂĄrias Ă terapĂȘutica padrĂŁo preconizada. Sucesso clĂnico foi registrado em cinco de seis pacientes com eumicetoma e cinco de seis pacientes com cromoblastomicose. Em dois pacientes observou-se doença estĂĄvel. Como parte do protocolo de extensĂŁo do tratamento, dois pacientes com eumicetoma que inicialmente tinham tido sucesso terapĂȘutico e que apĂłs um intervalo maior de 10 meses apresentaram recidiva da micose, foram retratados com sucesso com posaconazol. Posaconazol foi bem tolerado durante o longo perĂodo de administração (atĂ© 1015 dias). A terapĂȘutica com posaconazol foi seguida de sucesso na maioria dos pacientes com eumicetoma ou cromoblastomicose refratĂĄria Ă terapĂȘutica padrĂŁo, sugerindo que tal droga possa ser uma importante opção no tratamento de tais doenças