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751.
Enock Warinda Dickson M Nyariki Stephen Wambua Reuben M Muasya Munir A Hanjra 《Natural resources forum》2020,44(1):3-39
Investments in agricultural technologies, capacity building and policy harmonization are needed to support sustainable development across Africa. Regional development projects can facilitate the adoption of agricultural technologies and innovations across nation-state borders and generate benefits for shared prosperity. This paper uses panel data from 1,160 smallholder households including beneficiaries and non-beneficiaries from five countries in East Africa - Burundi, Kenya, Rwanda, Tanzania, and Uganda. From a pool of over 90 projects implemented over a span of 15 years, 23 regional projects are included in this study. The major economic benefits to smallholder participants are higher crop productivity and income, access to adaptable technologies, access to markets, higher livestock and milk production, gender equality, enhanced food security, resilience and capacity building for uptake and scaling up of future innovation platforms. For example, the adoption of low-cost tissue culture banana by the beneficiaries increased their incomes by 15% in Rwanda while the adoption of appropriate land and water management technologies increased the potato yields from 2.8 tons (USD 2,840/ha) to over 7.5 tons (USD 7,410/ha) in Kenya. The beneficiaries ensured value added to commodities like bananas (for export) and orange-fleshed sweet potatoes (a nutrition-sensitive intervention for enhancing domestic intake of vitamin A) in Burundi, Kenya, Rwanda and Uganda. Additionally, milk production increased from 6 to 11 L per cow per day in Uganda and from 6 to 8 L per cow per day in Tanzania, with increases in sales generating USD 115 per cow per month above the non-beneficiaries. These results are supported by previous studies on technology adoption, investments in agriculture and well-being outcomes. Our findings with the higher farm income Difference-in-Differences (DiD) estimator for the female beneficiaries compared to male beneficiaries might have important implications for investing in regional development projects that will close the gender gap in agricultural productivity in Africa. Regional projects can also support post-conflict development efforts for food security and peace in fragile contexts such as in Burundi. Our findings might serve as an input to the African Union's Comprehensive Africa Agriculture Development Programme, localization of the United Nations Sustainable Development Goals related to food security and agriculture in Africa and an input to monitoring, evaluation and learning. 相似文献
752.
Jeremy P. Bird Robert Martin H. Reşit Akçakaya James Gilroy Ian J. Burfield Stephen T. Garnett Andy Symes Joseph Taylor Çağan H. Şekercioğlu Stuart H. M. Butchart 《Conservation biology》2020,34(5):1252-1261
Birds have been comprehensively assessed on the International Union for Conservation of Nature (IUCN) Red List more times than any other taxonomic group. However, to date, generation lengths have not been systematically estimated to scale population trends when undertaking assessments, as required by the criteria of the IUCN Red List. We compiled information from major databases of published life-history and trait data for all birds and imputed missing life-history data as a function of species traits with generalized linear mixed models. Generation lengths were derived for all species, based on our modeled values of age at first breeding, maximum longevity, and annual adult survival. The resulting generation lengths varied from 1.42 to 27.87 years (median 2.99). Most species (61%) had generation lengths <3.33 years, meaning that the period of 3 generations—over which population declines are assessed under criterion A—was <10 years, which is the value used for IUCN Red List assessments of species with short generation times. For these species, our trait-informed estimates of generation length suggested that 10 years is a robust precautionary value for threat assessment. In other cases, however, for whole families, genera, or individual species, generation length had a substantial impact on their estimated extinction risk, resulting in higher extinction risk in long-lived species than in short-lived species. Although our approach effectively addressed data gaps, generation lengths for some species may have been underestimated due to a paucity of life-history data. Overall, our results will strengthen future extinction-risk assessments and augment key databases of avian life-history and trait data. 相似文献
753.
Musah Mohammed Kong Yusheng Mensah Isaac Adjei Antwi Stephen Kwadwo Donkor Mary 《Environment, Development and Sustainability》2021,23(8):11525-11552
Environment, Development and Sustainability - This study examined the nexus between urbanization and carbon emissions in West Africa. Second-generation econometric techniques that are robust to... 相似文献
754.
Dick Morris Sue Oreszczyn Christine Blackmore Raymond Ison Stephen Martin 《Local Environment》2013,18(6):683-699
Abstract Defining and putting into practice sustainable land use is a complex, systemic problem. Systems models and techniques were used in a study of Herefordshire to clarify the situation and identify the potential for a more locally focused, learning-based approach to land use. Issues included: (i) uncertainty about the boundary of a ‘system of sustainable Herefordshire land use’; (ii) the complexity of economic flows in the county and the absence of some critical data; (iii) the importance of the Herefordshire landscape to tourism and the role of agriculture as a determinant of the state of that landscape; (iv) weakness of the institutional linkage between tourism and agriculture; (v) the current lack of inclusion of many relevant stakeholders in concerted action. Factors favouring a learning approach included a strong local identity, local food-related developments, and educational initiatives. Barriers to such an approach included questions of power and landholding, government policies, and attitudes and skills within organizations. These findings are considered in relation to the wider debate over approaches to sustainability. 相似文献
755.
Richard A. Mbih Steven L. Driever Stephen K. Ndzeidze Mbongowo J. Mbuh Carine S. Bongadzem Harry M. Wirngo 《Environment, Development and Sustainability》2018,20(2):789-807
The Fulani pastoralists of the Western Highlands of Cameroon are a subgroup of the Fulbe, a wider pastoral group whose members are dispersed across Sub-Saharan Africa. They migrated and settled in the region in the early twentieth century at different times in migratory waves. Since arriving in the region, they have experienced different stages of transformation due to changing socioeconomic, political and ecological conditions influencing their nomadic lifestyle. The Fulani pastoralists have moved from a purely nomadic lifestyle that involved permanent seasonal migration with their herds and families to a semi-nomadic lifestyle involving return to their previous settlements at the end of each transhumance season, and they finally have adopted a more sedentary community lifestyle that involves only the seasonal movement of herdsmen and their cattle during dry periods. This pastoralist transformation process was motivated by the hospitality of native farming communities, the British colonial administration and postcolonial government of Cameroon, population growth and environmental degradation in the Western Highlands of grazing and cultivable land. This transformation has been beneficial to both pastoralists and native farming groups by improving local community development through increased agro-pastoral production and the realization of communal development projects in education and non-agro-pastoral economic activities. Several challenges have confronted this Fulani pastoralist transformation and its community development in the Western Highlands of Cameroon: landuse competition involving farmer–herder conflicts and inter-tribal wars; climate change, including rainfall variability; and environmental degradation including the disappearance of agro-pastoral lands. This paper, based on field research, investigates the various approaches, benefits and challenges involved in Fulani pastoralists’ settlement transformation in the Western Highlands of Cameroon. 相似文献
756.
757.
Freshwater aquaculture plays an important role in the economy of Bangladesh, providing food, income, livelihoods and export earnings. However, freshwater aquaculture in the Mymensingh area of north-central Bangladesh has been accompanied by recent concerns over climate change. Field survey revealed that different climatic variables including flood, drought, rainfall variation and temperature fluctuation have had adverse effects on pond-fish culture. These climatic variables have detrimental effects on the ecosystem of ponds and thus affect survival, growth and production of fish. Changes in climatic variables have adverse effects on fish reproduction, grow-out operation, parasite infestation and disease occurrence. Considering vulnerability to the effects of climate change on pond-fish culture, we propose adaptation strategies that need to be introduced to cope with the challenges. 相似文献
758.
759.
760.
Ruth R. Brockman Carmen T. Agouridis Stephen R. Workman Lindell E. Ormsbee Alex W. Fogle 《Journal of the American Water Resources Association》2012,48(2):391-406
Brockman, Ruth R., Carmen T. Agouridis, Stephen R. Workman, Lindell E. Ormsbee, and Alex W. Fogle, 2012. Bankfull Regional Curves for the Inner and Outer Bluegrass Regions of Kentucky. Journal of the American Water Resources Association (JAWRA) 48(2): 391‐406. DOI: 10.1111/j.1752‐1688.2011.00621.x Abstract: Bankfull regional curves that relate channel dimensions and discharge to watershed drainage area are useful tools for assisting in the correct identification of bankfull elevation and in stream restoration and reconstruction. This study assessed 28 stable streams located in two physiographic regions of Kentucky: the Inner Bluegrass and the Outer Bluegrass. Bankfull channel dimensions, discharge, and return period as well as average channel slope, median bed material size, sinuosity, Rosgen stream classification, and percent impervious area were determined. Significant relationships were found between drainage area and the bankfull characteristics of cross‐sectional area, width, mean depth, and discharge for both the Inner Bluegrass and Outer Bluegrass regions (α = 0.05). It was also found that the percent impervious area in a watershed had minimal effect on bankfull dimensions, which is attributed to the well‐vegetated nature of the streambanks, cohesive streambank materials, and bedrock control. No significant differences between any of the Inner Bluegrass and Outer Bluegrass regional curves were found (α = 0.05). Comparisons were made between the Inner Bluegrass and Outer Bluegrass curves and others developed in karst‐influenced areas in the Eastern United States. Although few significant differences were found between the regional curves for bankfull discharge and width, a number of the curves differed with regards to bankfull cross‐sectional area and mean depth. 相似文献