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11.
《Scandinavian Journal of Forest Research》2012,27(2):200-209
Abstract It is claimed that reduced emissions from deforestation and forest degradation (REDD) could contribute to sustainable management of forests and enhancement of forest carbon stocks as well as having the potential to deliver significant social and environmental co-benefits (+). From the perspectives of local factors and broader governance issues related to REDD+, this study aims to explore findings related to three crucial elements, commitment, transparency and continuity, implemented jointly with participatory forest management in Tanzania in the case of the REDD+ mechanism. This paper argues that commitment and transparent systems are needed at village level, as well as at the various levels of forest governance and among the donors, in order for REDD+ benefits to be shared equitably at the REDD+ project level. Any REDD+ project should include safeguards that recognise and protect the continuity of multipurpose functions of the forest to local people and avoid dependence on external payments. 相似文献
12.
Counts of bushbuck tracks were used to estimate their population densities. Good correlations were obtained between various indices of track frequency and estimated absolute population density. The technique is therefore recommended for assessing the absolute density of a population. High sampling costs, however, disqualify the technique for detecting small changes in density. 相似文献
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14.
M. M. Keregero K. Mtebe 《Plant foods for human nutrition (Dordrecht, Netherlands)》1994,46(4):305-312
The acceptability of sorghum as human food has been a problem in Tanzania even in regions showing promising potential for its production and utilization. Reasons given for low acceptability of sorghum products as human foods include unpleasant colour, aroma, mouthfeel, taste, unpleasant aftertaste and stomachfeel. An acceptability test of selected sorghum products was, therefore, conducted in the Department of Food Science and Technology, Sokoine University of Agriculture, Morogoro, Tanzania. The objective of the test was to determine consumers' preference for the following wheat-sorghum composite flour products: bread and buns or maandazi. The products were prepared using sorghum flour composited with wheat flour in the following proportions: 100% brown sorghum flour (standard products); and 80:20%; 60:40%; 40:60% and 20:80% for wheat/sorghum (white and brown) composite flours. Results indicated that in the case of composite flour bread, preference for the product improved as the amount of sorghum flour decreased. In the case of buns or maandazi the 100% sorghum flour products of both white and brown were equally preferred. Buns prepared from 100% sorghum flour of white and brown varieties showed promising potential in the improvement of the acceptability of sorghum products. Taking advantage of such products, especially in villages, could enhance sorghum utilization in rural communities. 相似文献
15.
Norman Owen-Smith 《Landscape Ecology》2004,19(7):761-771
Large mammalian herbivores are notorious for their propensity towards population irruptions and crashes, yet many herbivore populations remain relatively stable. I explore how resource heterogeneity within landscapes dampens population instability, using a metaphysiological modelling approach considering patch state distributions. Resource heterogeneity is functionally stabilizing through spreading consumption away from preferred resources before these become critically depleted. Lower-quality resources act as a buffer against starvation during critical periods of the seasonal cycle. Enriching resource quality is destabilizing, even if patch diversity is maintained, because food quantity then becomes the limitation. The potential consequences of landscape fragmentation are explored using the Serengeti ecosystem, characterised by broadscale resource gradients, as a hypothetical example. Further insights provided by the model are illustrated with specific examples concerning the effects of patch scales and waterpoint distribution. A metaphysiological modelling approach enables the basic consequences of landscape heterogeneity to be distinguished from further effects that may arise from specific patch scales and configurations, without the distracting detail of spatially explicit models. 相似文献
16.
Elin Enfors Jennie Barron Hodson MakuriraJohan Rockström Siza Tumbo 《Agricultural Water Management》2011,98(11):1687-1695
Yield levels in smallholder farming systems in semi-arid sub-Saharan Africa are generally low. Water shortage in the root zone during critical crop development stages is a fundamental constraining factor. While there is ample evidence to show that conservation tillage can promote soil health, it has recently been suggested that the main benefit in semi-arid farming systems may in fact be an in situ water harvesting effect. In this paper we present the result from an on-farm conservation tillage experiment (combining ripping with mulch and manure application) that was carried out in North Eastern Tanzania from 2005 to 2008. Special attention was given to the effects of the tested treatment on the capacity of the soil to retain moisture. The tested conservation treatment only had a clear yield increasing effect during one of the six experimental seasons (maize grain yields increased by 41%, and biomass by 65%), and this was a season that received exceptional amounts of rainfall (549 mm). While the other seasons provided mixed results, there seemed to be an increasing yield gap between the conservation tillage treatment and the control towards the end of the experiment, and cumulatively the yield increased with 17%. Regarding soil system changes, small but significant effects on chemical and microbiological properties, but not on physical properties, were observed. This raises questions about the suggested water harvesting effect and its potential to contribute to stabilized yield levels under semi-arid conditions. We conclude that, at least in a shorter time perspective, the tested type of conservation tillage seems to boost productivity during already good seasons, rather than stabilize harvests during poor rainfall seasons. Highlighting the challenges involved in upgrading these farming systems, we discuss the potential contribution of conservation tillage towards improved water availability in the crop root zone in a longer term perspective. 相似文献
17.
J. D. Keyyu N. C. Kyvsgaard J. Monrad A. A. Kassuku 《Tropical animal health and production》2009,41(1):25-33
A longitudinal field trial was conducted to determine the effectiveness of strategic anthelmintic treatments in the control
of gastrointestinal (GI) nematodes and Fasciola gigantica in cattle. A total of 167 cattle (6–18 months) from three large-scale dairy farms, four traditional farms and nine small-scale
dairy farms were randomly selected. The selected animals on each farm were ear tagged and allocated into three groups based
on live weight and treated as follows: Group T4 was treated with albendazole 10% drench at 10 mg/kg four times a year (mid
rainy, end of the rain, mid dry and late dry/early rainy season). Group T2 was treated with albendazole 10% drench at 10 mg/kg
two times a year (mid rainy and late dry/early rainy season). Group UT remained as untreated control. Faecal, blood and pasture
samples were taken every month for 13 months. In addition, individual body weight (BWT) was measured on every sampling date.
Results showed that two and four strategic treatments significantly reduced faecal egg counts (FEC) by 49.5% and 62.3% respectively
compared to untreated control animals (P < 0.001). Two and four strategic treatments per year significantly reduced the proportion
of animals passing Fasciola eggs in faeces by 30.6% and 51.7% (P < 0.001), respectively. Animals treated two and four times a year significantly outgained
untreated animals by 14.8 kg and 17.7 kg respectively at the end of the trial (P < 0.05). The management system had a significant
effect on packed cell volume and the proportion of animals passing Fasciola eggs in faeces (P < 0.05). The programme of two strategic treatments per year was only effective in controlling GI nematodes.
It is concluded that a programme of four strategic treatments per year was effective in controlling GI nematodes and F. gigantica and improved weight gain. 相似文献
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19.
Sadruddin F. H. Jiwa Rudovick R. Kazwala Romuald Tungaraza Sharadhuli I. Kimera William J. Kalaye 《Preventive veterinary medicine》1996,26(3-4):341-346
A total of 13078 cattle 8 months of age and older belonging to 558 units in the Lake Victoria zone of Tanzania were screened for brucellosis using the serum agglutination test (SAT). This exercise was executed as a Tanzanian Agriculture Ministry's directive for screening all adult bovines in the country reared under controlled grazing and receiving good veterinary supervision and inputs so that brucellosis control measures could be instituted. In this category two types of management systems were encountered: Dairy, comprising 15 units totalling 3626 Exotic (Friesian and Ayrshire) and Grade (Zebu and Exotic) crosses, and Ranch, comprising two units totalling 6756 mainly dual-purpose Mpwapwa (MPW) animals. These three animal types have much higher milk production potential than the indigenous Tanganyika shorthorn Zebu (TSZ). This latter beef type is reared under local management system and owned wholly by subsistence stock owners practising uncontrolled communal grazing and having little or no veterinary supervision and inputs. However, TSZ animals from 541 farm units totalling 2705 members were also screened from the east and south sub-zones because of their close proximity to the Dairy/Ranch units and also the Serengeti Wildlife National Park. This exercise revealed an overall prevalence rate of 10.8%. There was moreover a significant difference in the seroprevalence rates among the management systems (P < 0.001). The lowest prevalence rate (4.3%) was found in the Local management system, with Dairy intermediate (6.3%) and Ranch highest (15.8%). There was also significant variation in prevalence rates between TSZ and Grade animals, and between MPW and Exotic animals (P < 0.001). 相似文献
20.
This paper presents experience on working with farmers in water scarce environments in improving crop yield through the application of locally available materials in semi-arid areas of Mpwapwa District, central Tanzania. Findings are presented from the interdisciplinary study that involved documenting farmers perceptions and on-farm field experimentation. In the farmers’ perceptions study, three different traditional tillage practices applied by smallholder farmers in the area were identified. These are traditional no-till (TNT), shallow tillage (ST) and ridging tillage (RT). The impacts of various tillage practices on soil fertility improvement, reduced weed infestation, soil moisture retention and crop yield were the main factors considered by farmers when selecting a particular tillage practice to apply. In two cropping seasons (i.e. 2006/7 and 2007/8) on-farm field experimentations were carried to test the effects of the three traditional tillage practices, manure and mulching practices on soil moisture retention and crop yield. Results from this experiment showed traditional no-till fields to have the lowest soil moisture retention capacity and the lowest infiltration flow rate as well as lowest crop yield compared to other studied practices. It was observed that improving the current tillage practices by the application of manure to both ST and RT, and mulching to ST at rates affordable to smallholder farmers as identified during perception study (i.e. 5 tons/ha for manure and 3 tons/ha for mulching materials) results in increased crop yield. When the grain yield is compared between traditional no-till and shallow tillage with manure and mulching practices, the yield increase is between 50 and 100%. It was concluded that crop yield in water scarce environments such as the semi-arid areas of Mpwapwa District can be increased by applying locally available materials such as cow manure and mulching at rates affordable to smallholder farmers. 相似文献