109 research outputs found
APC Communiqué
This is the archive of the summer 2012 APC Communiqué, a bi-annual newsletter, which features a special report entitled, "President Rupiah Banda defends democracy in Zambia and Africa". Banda was APC's eighth President-in-Residence
Inquiry into the interests of certain eighth-grade science pupils
Thesis (Ed.M.)--Boston University, 1946. This item was digitized by the Internet Archive
Utilization of non-timber forest products as alternative sources of food and income in the highland regions of the Kahuzi-Biega National Park, eastern Democratic Republic of Congo
peer reviewedIn developing countries, studies on sustainable preservation of forests (including non-timber forest products NTFPs) have been poorly carried out for promoting alternative income generating activities (IGA) to alleviate pressure on praised resources by local communities living close by protected areas. This study aimed at (1) inventorying NTFPs exploited by local communities around the Kahuzi Biega National Park (KBNP), (2) assessing their therapeutic values and nutritional contributions, and (3) analyzing their rural and urban market values to determine their potential as alternative income sources as well as the major constraints in their exploitation. Individual interviews were conducted with 790 rural and urban households in Kabare, Walungu, Kalehe, and Bukavu City, eastern Democratic Republic of Congo (DRC) coupled with focus group discussions with key stakeholders around KBNP. Street vendors, restaurants, hotels, and market owners were also interviewed on uses, awareness of the nutritional and therapeutic values, and factors hindering NTFPs wide use in Bukavu urban environments. Physicochemical analyses were also conducted on main NTFPs to determine their nutritional values. Results showed that local populations around KBNP exploit at least 55 NTFPs, mainly for self-consumption as food, feed, and medicine. NTFPs represent the second most important income source around KBNP, accounting for 23.3 % of total households’ income after agriculture that generates 25.7 % of total households’ income. Income from NTFP trade was primarily used for food supply (29 %), investment in small businesses (19.6 %), children's education (17.7 %), and healthcare expenses (5.1 %). These NTFPs had varying nutritional values (in terms of proximate composition, essential minerals, and bioactive compounds). Solanum nigrum (24.9 %), Termitomyces robustus (18.0 %), Amaranthus viridis (17.6 %), and Piper nigrum (16.9 %) are valuable sources of proteins while Zingiber officinale (25.5 %), T. robustus (15.4 %) and P. nigrum (14.3 %) are rich in dietary fibres. Piper nigrum (37.0 and 128.3 mg/kg) and Basella alba (35.1 and 108.7 mg/kg) had the highest zinc and iron contents, respectively. Some of the most nutritious NTFPs, such as S. nigrum, Dioscorea spp., and P. nigrum had high contents in anti-nutritional elements and should be processed properly to maximize bioavailability. Besides, NTFPs created employment opportunities for collectors, vendors, supermarkets, hotels, and restaurants both in rural and urban areas. Though varying with rural communities, the main challenges in the NTFP value chain were low market values (48.6 %), short shelf life (22.5 %), and excessive taxation (19.1 %) while in urban areas, seasonality (36.9 %), scarcity (17.7 %), and prohibiting high prices (17.7 %) were the major limiting factors. This study highlights the significant role played by NTFPs in providing healthy and nutritious food and income for households surrounding the KBNP, and thus emphasizes the necessity for their promotion as alternative income sources and healthy diets to alleviate poverty and hidden hunger around the KBNP
Predicting the Electron Requirement for Carbon Fixation in Seas and Oceans
Marine phytoplankton account for about 50% of all global net primary productivity (NPP). Active fluorometry, mainly Fast Repetition Rate fluorometry (FRRf), has been advocated as means of providing high resolution estimates of NPP. However, not measuring CO2-fixation directly, FRRf instead provides photosynthetic quantum efficiency estimates from which electron transfer rates (ETR) and ultimately CO2-fixation rates can be derived. Consequently, conversions of ETRs to CO2-fixation requires knowledge of the electron requirement for carbon fixation (Φe,C, ETR/CO2 uptake rate) and its dependence on environmental gradients. Such knowledge is critical for large scale implementation of active fluorescence to better characterise CO2-uptake. Here we examine the variability of experimentally determined Φe,C values in relation to key environmental variables with the aim of developing new working algorithms for the calculation of Φe,C from environmental variables. Coincident FRRf and 14C-uptake and environmental data from 14 studies covering 12 marine regions were analysed via a meta-analytical, non-parametric, multivariate approach. Combining all studies, Φe,C varied between 1.15 and 54.2 mol e- (mol C)-1 with a mean of 10.9±6.91 mol e- mol C)-1. Although variability of Φe,C was related to environmental gradients at global scales, region-specific analyses provided far improved predictive capability. However, use of regional Φe,C algorithms requires objective means of defining regions of interest, which remains challenging. Considering individual studies and specific small-scale regions, temperature, nutrient and light availability were correlated with Φe,C albeit to varying degrees and depending on the study/region and the composition of the extant phytoplankton community. At the level of large biogeographic regions and distinct water masses, Φe,C was related to nutrient availability, chlorophyll, as well as temperature and/or salinity in most regions, while light availability was also important in Baltic Sea and shelf waters. The novel Φe,C algorithms provide a major step forward for widespread fluorometry-based NPP estimates and highlight the need for further studying the natural variability of Φe,C to verify and develop algorithms with improved accuracy. © 2013 Lawrenz et al
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