Climate variability and change are among the biggest challenges of the 21st century. Like in many other areas globally, the coastal communities of Tanzania have always been facing climatic variability at various time ...Climate variability and change are among the biggest challenges of the 21st century. Like in many other areas globally, the coastal communities of Tanzania have always been facing climatic variability at various time scales. Using focus group discussion and a household survey, this study analyzes the perceptions of climate variability and change and the strategies for coping and adaptation by the selected coastal rural and peri-urban communities in Tanzania. The perception of climate variability and change is complemented with the time-series analysis of rainfall and temperature data from Julius Nyerere International Airport Met. station and Kisarawe using Instant Statistical Software. Results indicate that households are aware of climate variability and identify indicators of climate change and variability as being decreasing rainfall trends, increasing incidences of droughts, unpredictable rainfall patterns, disappearance of wetlands and failure to predict on-set of rainy season using traditional knowledge. Households primarily attribute reduced crop yields to changes in rainfall pattern and increasing incidences of drought leading to soil moisture stress. The implications are that the agriculture dependent households are now food insecure. As a way of coping to the observed changes, the coastal communities among others have shifted to production of high value horticultural crops and use of forest resources. Nevertheless, the increased use of forest resources is threatening the existence of coastal forests and contributes to the decline of forest resources and disappearance of wildlife in the forest reserves. It is concluded that the communities studied are aware of climate issues as revealed from perceived indicators of climate variability and changes. The results from statistical analysis of 30 years climatic data are consistent with community’s perception of climate variability and change. The study recommends examining the present coping strategies for the sustainability of the coastal forests and in designing of alternative adaptive strategies such as alternative energy options, crop diversification and environmental friendly activities such as beekeeping.展开更多
Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanza...Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1：50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base （FAO-WRB） for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/（＋）kg to 24 cmol/（＋）kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.展开更多
The tropical forest kapok tree occurs widely in urban environments, dispersing thousands of floss during the fruiting season. However, its seedlings are rarely seen around human settlements, raising questions on what ...The tropical forest kapok tree occurs widely in urban environments, dispersing thousands of floss during the fruiting season. However, its seedlings are rarely seen around human settlements, raising questions on what factorsmight be limiting its recruitment. We examined the pattern of floss release, seed fall post-dispersal and influences of watering frequency on germination ofCeiba pentandraseeds. Evening,overall, was associated with a significantlyhigher rate and quantity of floss release (p= 0.0001) than were mid-day and morning, correlating well with the speed of wind across the day (rh = 0.666,p= 0.001). Mean dispersal quantity differed significantly between the individual sampled trees, in which the highest dispersal was recorded from trees located in relatively open areas and the lowest was recorded in closed stand trees. Seed fall was higher within100 mdistances than seed fall farther away from dispersing trees, depending on the microsites and weather conditions. Germination started on day 5 onwards and only 15.67% of sown seeds germinated. Watering frequency strongly influenced seed germination while local human activities determined fate of dispersed seeds. We conclude that recruitment ofC. pentandraspecies in the study area may have been limited by environmental and human factors operating at various local and spatial scales.展开更多
Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these...Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these habitats in many tropical wetlands. To effectively restore these natural grasslands and conserve avifaunal biodiversity, understanding of the relationships between habitat conditions and bird community structure are central. We used a combination of information from nearby villagers and field surveys to establish two important grassland habitats with low and high disturbance histories, and related the habitats to bird community structure. We surveyed a total of 119 sites in the two habitats to examine variation in the abundance, richness, diversity and composition of birds at Kilombero Wetland Tanzania. In total, 3049 individuals, 126 species, 88 genera and 45 families were recorded from Kilombero grasslands. Our results show that grasslands with low human disturbance had more number of bird species, genera, families and diversity (both ShannonWiener and Simpson) than the most disturbed grasslands atp 0.05) between low and highly disturbed grassland habitats suggesting that other factors including variety of foraging sites are important. This study confirms that the wetland grasslands of Kilombero are important for conservation of birds including rare and endemic species. It is recommended that anthropogenic disturbancesshould be minimized including control of fire, regulation of agricultural activities and population of cattle within the wetland system to restore and conserve biodiversity.展开更多
文摘Climate variability and change are among the biggest challenges of the 21st century. Like in many other areas globally, the coastal communities of Tanzania have always been facing climatic variability at various time scales. Using focus group discussion and a household survey, this study analyzes the perceptions of climate variability and change and the strategies for coping and adaptation by the selected coastal rural and peri-urban communities in Tanzania. The perception of climate variability and change is complemented with the time-series analysis of rainfall and temperature data from Julius Nyerere International Airport Met. station and Kisarawe using Instant Statistical Software. Results indicate that households are aware of climate variability and identify indicators of climate change and variability as being decreasing rainfall trends, increasing incidences of droughts, unpredictable rainfall patterns, disappearance of wetlands and failure to predict on-set of rainy season using traditional knowledge. Households primarily attribute reduced crop yields to changes in rainfall pattern and increasing incidences of drought leading to soil moisture stress. The implications are that the agriculture dependent households are now food insecure. As a way of coping to the observed changes, the coastal communities among others have shifted to production of high value horticultural crops and use of forest resources. Nevertheless, the increased use of forest resources is threatening the existence of coastal forests and contributes to the decline of forest resources and disappearance of wildlife in the forest reserves. It is concluded that the communities studied are aware of climate issues as revealed from perceived indicators of climate variability and changes. The results from statistical analysis of 30 years climatic data are consistent with community’s perception of climate variability and change. The study recommends examining the present coping strategies for the sustainability of the coastal forests and in designing of alternative adaptive strategies such as alternative energy options, crop diversification and environmental friendly activities such as beekeeping.
文摘Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1：50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base （FAO-WRB） for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/（＋）kg to 24 cmol/（＋）kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.
文摘The tropical forest kapok tree occurs widely in urban environments, dispersing thousands of floss during the fruiting season. However, its seedlings are rarely seen around human settlements, raising questions on what factorsmight be limiting its recruitment. We examined the pattern of floss release, seed fall post-dispersal and influences of watering frequency on germination ofCeiba pentandraseeds. Evening,overall, was associated with a significantlyhigher rate and quantity of floss release (p= 0.0001) than were mid-day and morning, correlating well with the speed of wind across the day (rh = 0.666,p= 0.001). Mean dispersal quantity differed significantly between the individual sampled trees, in which the highest dispersal was recorded from trees located in relatively open areas and the lowest was recorded in closed stand trees. Seed fall was higher within100 mdistances than seed fall farther away from dispersing trees, depending on the microsites and weather conditions. Germination started on day 5 onwards and only 15.67% of sown seeds germinated. Watering frequency strongly influenced seed germination while local human activities determined fate of dispersed seeds. We conclude that recruitment ofC. pentandraspecies in the study area may have been limited by environmental and human factors operating at various local and spatial scales.
文摘Wetland natural grasslands are important habitats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricultural land have degraded these habitats in many tropical wetlands. To effectively restore these natural grasslands and conserve avifaunal biodiversity, understanding of the relationships between habitat conditions and bird community structure are central. We used a combination of information from nearby villagers and field surveys to establish two important grassland habitats with low and high disturbance histories, and related the habitats to bird community structure. We surveyed a total of 119 sites in the two habitats to examine variation in the abundance, richness, diversity and composition of birds at Kilombero Wetland Tanzania. In total, 3049 individuals, 126 species, 88 genera and 45 families were recorded from Kilombero grasslands. Our results show that grasslands with low human disturbance had more number of bird species, genera, families and diversity (both ShannonWiener and Simpson) than the most disturbed grasslands atp 0.05) between low and highly disturbed grassland habitats suggesting that other factors including variety of foraging sites are important. This study confirms that the wetland grasslands of Kilombero are important for conservation of birds including rare and endemic species. It is recommended that anthropogenic disturbancesshould be minimized including control of fire, regulation of agricultural activities and population of cattle within the wetland system to restore and conserve biodiversity.
