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Analytical methods for Cyhalofop-butyl and its metabolites in Soil and water
(China academic journal electronic publishing house, 2001) Mwalilino, Jilisa K; L i, Zhao; Guonian, Zhu; Yingxu, Chen
A relatively simp le and less expensive m ethod is p ropo sed fo r the determ ination of cyhalofop2butyl (XDE2537) and its m etabo lites: R2(+ ) 222[ 42(22fluo ro242 cyanophenoxy) phenoxy ] p ropano ic acid (AC ID ); R2(+ ) 222[42 (42 carboxyl222fluo ro242 cyanophenoxy) phenoxy ] p ropano ic acid ( D IAC ID ); and 22[42(42carbamoyl222 fluo rophenoxy) phenoxy ] p ropano ic acid (AM IDE). Conversion of the parent compound to its arylöalkylöo r halide derivative fo r determ ination by GC w as found unnecessary. O nly HPLC w as used and under gradient elution all the four compounds separated w ell. Good recoveries w ere obtained w ith the fo rtified so il and w ater samp les. Low pH w as impo rtant fo r the extraction of the four components
Response of gstase and L iver esterase in goldf ish (Ca rra sius aura tus) and topmouth gudegon (Pseudora sboraparva ) after sublethal exposure to cyhalofop-butyl and profur ite-am in ium
(Chinese journal of pesicide science, 2002) ZHU, Guo-nian; Hui ming, WU; Mwalilino, Jilisa K.; Shao-nan, L I
Investigations w ere carried to assess the sublethal effects of a herbicide clincher ( 100 EC) containing cyhalofop2butyl [ 100 g (a. i) ·L - 1 ] as the active ingredient and the insecticide p rofurite2am inium [ 78% SP, 780 g (a. i) ·kg - 1 ] on liver esterases and hepatic glutath ione2S 2transferase (GST ) in go ldfish (Carassius au ratus) and topmouth gudgeon (P seud orasbora p arva). GST w as found to be induced in bo th go ldfish and topmouth gudgeon by the p rofurite2am inium at concentration of 0. 234 m g·L - 1 . Clincher bo th at concentration of 1 and 2 m g·L - 1 caused GST induction in topmouth gudgeon. The m ixture of clincher and p rofurite2am inium had the h ighest effect in topmouth gudgeon 722. 3 nmo l· (m in - 1·m g - 1 p ro tein ) w ith a po ssible indication of additive toxicity. L iver esterases w ere induced by bo th clincher (1 and 2m g·L - 1 ) and p rofurite2am inium (0. 117 and 0. 234m g·L - 1 ) in go ldfish. In topmouth gudgeon liver esterases w ere induced by p rofurite2am inium but inh ibited by clincher. It is suggested that the two bio transfo rm ation enzym es m ay be directly o r indirectly affected by the tested chem icals and that there are differences betw een them
Household waste recovery and recycling: a case study of Kigoma-Ujiji, Tanzania
(Inderscience Enterprises Ltd, 2003) Shams, Shahriar; Ibrahimu, Chikira
Management of waste in most developing countries has become important for most of the cities as they try to curb and control city growth and urbanisation. The general norm where waste management had been the sole duty of municipalities has proved not to work due to lack of funds, public participation, political will and awareness. This paper looks at the general problems faced in household waste recovery and recycling, with a case study from Tanzania. A process scheme that consists of public participation, costs, social acceptance, economic benefits, and hygiene is considered. The overall conclusion is that there is a need for government commitment and general involvement of the public. The setting up of recycling industries will also ease the situation and at the same time create employment for the people.
The biological importance of the Eastern Arc Mountains of Tanzania and Kenya
(Elsevier, 2006-10) Burgess, N.D.; Butynski, T.M.; Cordeiro, N.J.; Doggart, N.H.; Fjeldså, J.; Howell, K.M.; Kilahama, F.B.; Loader, S.P.; Lovett, J.C.; Mbilinyi, B.; Menegon, M.; Moyer, D.C.; Nashanda, E.; Perking, A.
The Eastern Arc Mountains are renown in Africa for high concentrations of endemic Received 17 June 2005 species of animals and plants. Thirteen separate mountain blocks comprise the Eastern Received in revised Arc, supporting around 3300 km 2 of sub-montane, montane and upper montane forest, less form 29 June 2006 than 30% of the estimated original forested area. At least 96 vertebrate species are endemic, Accepted 8 August 2006 split as follows: 10 mammal, 19 bird, 29 reptile and 38 amphibian species. This includes Available online 12 October 2006 four endemic or nearly endemic species of primate – the Sanje Mangabey, the Iringa Red Colobus, the Mountain Galago and the new Kipunji monkey that forms its own monotypic Keywords: genus. A further 71 vertebrate species are near-endemic. At least 800 vascular plant species Biodiversity conservation are endemic, almost 10% of these being trees. These endemics include the majority of the Eastern Arc Mountains species of African violet – Saintpaulia, a well-known flowering plant in Western households. Protected areas An additional 32 species of bryophytes are also endemic. Many hundreds of invertebrates Diversity are also likely to be endemic, with data for butterflies, millipedes and dragonflies indicating Endemism potential trends in importance. Seventy-one of the endemic or near-endemic vertebrates are threatened by extinction (8 critical, 27 endangered, 36 vulnerable), with an additional seven wide ranging threatened species. Hundreds of plant species are also threatened
Groundwater exploitation and hydraulic parameter estimation for a Quaternary aquifer in Dar-es-Salaam, Tanzania.
(Elsevier Ltd, 2009-07-03) Mjemah, Ibrahimu Chikira; Van Camp, Marc; Walraevens, Kristine
The fact that groundwater exploitation has largely increased since 1997 in the Dar-es-Salaam aquifer, calls for a directed attention towards possible problems of aquifer overexploitation that may arise in the near future. Hydraulic parameters are important for developing local and regional water plans as well as developing numerical groundwater flow models to predict the future availability of the water resource. The determination of aquifer parameters through pumping tests has become a standard step in the evaluation of groundwater resource potential. The pumping tests in the study area were con- ducted in August 2004 and August 2005, where 39 boreholes were tested out of 400 visited. In the study area there are over 1300 recorded boreholes drilled by Drilling and Dam Construction Agency (DDCA) by the year 2005. Total groundwater exploitation in the study area was estimated at 8.59 10 6 m 3 /year, based on yield data collected during the 2004–2005 field campaigns. The pumping tests included single- well tests and tests with measurements on the pumping well and at least one observation well. The tests were conducted for 6 h and 30 min. The pump was shut down after 6 h of pumping and the remaining 30 min were used for recovery measurements. The pumping test analysis methods used include: Neuman type curve matching and Walton type curve matching, checked by specific well capac- ity assessment and Thiem–Dupuit/Thiem’s method. The curve-matching results from the aquifer tests show the following parameters: an average transmissivity and hydraulic conductivity of 34 m 2 /d and 1.58 m/d, respectively for the unconfined aquifer; the semi-confined aquifer has an average value of 63 m 2 /d and 2.14 m/d for transmissivity and hydraulic conductivity, respectively. For the case of the storativity, the unconfined aquifer has an average elastic early-time storativity of 0.01, while the lower aquifer has an average storativity of 3 10 4 . Specific well capacity method and Thiem–Dupuit/Thiem’s method confirm results for transmissivity and hydraulic conductivity of the semi-confined aquifer, while values for the unconfined aquifer are somewhat larger (by a factor of 2–3). The hydraulic param- eters calculated appear to reasonably agree with the geological formation of the aquifers, as deduced from borehole descriptions.
Conservation implications of deforestation across an elevational gradient in the Eastern Arc Mountains, Tanzania
(Elsevier, 2009-11) Burgess, Neil D.; Mbilinyi, Boniface; Gereau, Roy E.; Hall, Jaclyn; Lovett, Jon
Deforestation is a major threat to the conservation of biodiversity, especially within global centers of endemism for plants and animals. Elevation, the major environmental gradient in mountain regions of the world, produces a rapid turnover of species, where some species may exist only in narrow elevational ranges. We use newly compiled datasets to assess the conservation impact of deforestation on threatened trees across an elevational gradient within the Eastern Arc Mountains of Tanzania. The Eastern Arc has suffered an estimated 80% total loss in historical forest area and has lost 25% of forest area since 1955. Forest loss has not been even across all elevations. The upper montane zone (>1800 m) has lost 52% of its paleoecological forest area, 6% since 1955. Conversely, the submontane habitat (800–1200 m) has lost close to 93% of its paleoecological extent, 57% since 1955. A list of 123 narrowly endemic Tanzanian East- ern Arc tree taxa with defined and restricted elevational ranges was compiled and analyzed in regard to mountain block locations, elevational range, and area of forest within each 100 m elevational band. Half of these taxa have lost more than 90% of paleoecological forest habitat in their elevational range. When elevational range is considered, 98 (80%) of these endemic forest trees should have their level of extinc- tion threat elevated on the IUCN Red List. Conservation efforts in montane hotspots need to consider the extent of habitat changes both within and across elevations and target conservation and restoration efforts throughout these ecosystems’ entire elevational ranges.
Groundwater vulnerability to petroleum hydrocarbons pollution of quaternary sand aquifer in Dar es Salaam, Tanzania
(The Journal of Building and Land Development., 2010) Mjemah, I. C.; Mato, R.R.A.M.; Thunvik, R.
Groundwater is inherently susceptible to contamination from anthropogenic activities and remediation is very expensive and often impractical. Prevention of contamination is hence critical in effective groundwater management. In this paper, an attempt has been made to assess the aquifer’s vulnerability to petroleum hydrocarbons contamination in Dar es Salaam City, Tanzania. Potential benefit from mapping vulnerability is that it aids in the prioritisation of monitoring boreholes located in high vulnerable area, as well as providing bases for developing appropriate groundwater protection strategies. The DRASTIC model coupled to ArcView-GIS and HSSM model were used in vulnerability assessment. The results from these models have clearly demonstrated that the aquifers in the Dar es Salaam City are likely to be affected from petroleum hydrocarbons, because the pollution sources are located to a moderate and high vulnerability class, which covers about 80% of the Dar es Salaam City. Furthermore, the gasoline estimated arrival time is about 1 year for transport from the ground surface to a water table aquifer at a depth of 7 m. The current situation of petroleum hydrocarbons found in potable water shows very low concentrations (<2.5g/l) compared to the limits of the Tanzania standards of about 0.5 mg/l. However, as the gasoline takes even decade or centuries to migrate through aquifers, the concentrations are likely to increase if no preventive measures are taken.
Integrating the management of the ruaha landscape of Tanzania with local needs and preferences
(University of California, 2010-01) Masozera, M.; Erickson, J.D.; Clifford, D. L.; Coppolillo, P.; Nguvava, M.; Sadiki, H.; Mazet, J. A .K.
ustainable management of landscapes with multiple competing demands requires balancing the diverse preferences and needs of stakeholder groups. Conservation and development organizations have often made unwarranted assumptions about what is desired by, or good for local people without engaging local stakeholders. This study uses conjoint analysis to assess the preferences of representatives from three stakeholder groups—local communities, district government officials, and non-governmental organizations (NGOs)—to identify potential competing conservation and development priorities facing local communities in the Ruaha Landscape of Tanzania. Representatives of local agricultural communities place high importance on investments in farmer’s cooperatives that increase accessibility to supplies, loans, and capacity development. In contrast, district government officials and NGOs perceive investments to improve health, education, and tourism infrastructure as highest priorities for the region. Analysis suggests a need for incorporating issues deemed important by these various groups into a development strategy that aims to promote conservation of the Ruaha Landscape while improving the livelihoods of local communities. To be successful, future projects, whether conservation or development, must reconcile objectives at local to global scales and across sectors.
The potential of hyper-temporal NDVI data to assess vegetation condition and grazing intensity
(International Institute for Geo-information Science and Earth Observation, 2010-02) Hamad, Amina Amri
Land degradation has been reported to be a major environmental problem in Crete for a long time and is largely caused by excessive grazing. Several attempts have been done using satellite images for the purpose of monitoring the effect of excessive grazing on vegetation as a whole and their distribution. These studies lacked the temporal aspects of monitoring grazed lands since they used satellite imagery of one date. This study used 10 years MODIS hyper temporal NDVI images of 16 days temporal resolution to assess vegetation condition and grazing intensity. Grazed areas were classified by vegetation types into 8 groups. Grass Index measured from field was used as a direct estimate of Grazing Index. Seasonal analysis was done where the pixel NDVI value at the peak and at the end of grazing season was compared separately to Grazing Index to assess vegetation conditions. Not only that but also trend analysis was used to assess vegetation conditions, where the slope of 10 years NDVI was compared to the Grazing Index by vegetation types. Assessment of Grazing Intensity was done by comparing the difference of NDVI at the peak and end of grazing season with the Grazing Index. Seasonal analysis showed that at a confidence interval of 0.05 four groups had significant positive relation between the NDVI at a peak of growing season and grazing index and one had a negative relation. Moreover trend analysis revealed that at a confidence level of 0.15 two groups had significant positive and negative relation between slope of 10 years NDVI and grazing index. These analysis indicate that different vegetation types have different response to high grazing intensities. NDVI difference was found to have a positive relation with Grazing Index indicating it is possible to use this method to estimate grazing intensity. Not only that but also R 2 ranged between 25%-87% which means the analysis explained sufficient variability. MODIS hyper temporal NDVI has shown a potential to assess vegetation conditions and grazing intensity however studies should be done more on how to capture the amount of brown biomass this could improve the estimates and monitoring of grazed lands.
Groundwater exploitation and recharge rate estimation of a quaternary sand aquifer in Dar-es-Salaam area, Tanzania
(Springer-Verlag, 2010-09-10) Mjemah, Ibrahimu Chikira; Van Camp, Marc; Martenes, Kristine; Walraevens, Kristine
Dar-es-Salaam City gets water supply from surface water and groundwater. The groundwater is used to supplement surface water supply and has increasingly become a major source of water supply in the city. The study area comprises three major parts: the central coastal plain with quaternary fluvial–deltaic sediments, the deltaic Mio-Pliocene clay-bound sands and gravels in the north- west and southeast and the Lower Miocene fluviatile sandstones of Pugu Hills in the west of the study area. The main objective of this study was to quantify the integrated water balance. The major source of renewable groundwater in the aquifer is rainfall. Hence, the average recharge of 256.2 mm/year (for the year 2006) to the aquifer was estimated using the balance method of Thornthwaite and Mather, which is equal to 99.4 hm 3 /year for the whole alluvial aquifer. This value was balanced with total groundwater abstraction of 8.59 hm 3 /year, baseflow to rivers of 75.7 hm 3 /year and discharge into the sea (15.11 hm 3 /year).
Enhancing protection of Dar es Salaam quaternary aquifer: Groundwater recharge assessment.
(Springer-Verlag, 2011) Mtoni, Y.; Mjemah, I. C.; Van Camp, M.; Walraevens, K.
Water balance for Dar es Salaam Quaternary coastal aquifer (DQCA) was calculated according to the method of Thornthwaite and Mather. Monthly potential evapotranspiration estimates were calculated from 39 years (1971–2009) of routine meteorological data using Penman-Monteith, Thornthwaite, Hargreaves and Hamon methods. Results were compared in order to show possible differences that could be attributed to the methods. Determination of groundwater recharge rates gave a mean value of 184 mm year -1 which is equivalent to 71.39 x 10 6 m 3 year -1 indicating that 16.5% of the long term average annual precipitation of 1114 mm ends up as groundwater recharge. Groundwater abstraction from DQCA was estimated to be 69.3 x 10 6 m 3 year -1 . These results are alarming in two aspects: high abstraction rate and the increasing trend of borehole drilling. Groundwater abstraction which is nearly equal to the amount of the groundwater recharge is far greater than the least conservative sustainable yield calculated at 70% (equivalent to 49.97 x 10 6 m 3 year -1 ).
Nitrate pollution of Neogene alluvium aquifer in Morogoro Municipality, Tanzania.
(International Formulae Group, 2011-02) Kibona, Irene; Mkoma, Stelyus L.; Mjemah, Ibrahimu C.
Concern over nitrate pollution of groundwater in integrated water quality management has been growing recently. The levels of nitrate in wells from septic tanks and urban agriculture with nitrogen fertilizers application may increase the potential groundwater pollution by nitrate. The purpose of this study was to determine the concentrations and spatial distribution of nitrate (NO 3 − ) in groundwater in Morogoro Municipality. Groundwater samples were collected from 20 wells during wet season period in March-April 2010 in 6 wards namely Kihonda, Mji Mpya, Mafisa, Saba Saba, Boma and Kilakala. The spectrophotometer was used to measure the NO 3 − concentration in water samples. The minimum and maximum nitrate levels were 1.4 and 32.5 mg/L respectively in the wards studied with an average of 7.76 mg/L. These results showed that all of the groundwater samples have NO 3 − concentration below the Tanzania Bureau of Standards upper limit value and World Health Organization guideline of 75 mg/l and 50 mg/l respectively. Also, the level of nitrate concentration tend to decrease with depth for most of the places due to the anoxic condition that is available at the higher depth which facilitates the utilization of nitrate by anaerobic microorganisms.
Influence of meteorology on ambient air quality in Morogoro, Tanzania
(International Journal of Enviromental Science., 2011-03) Mkoma, Stelyus L.; Mjemah, Ibrahimu C.
The influence of meteorological parameters on air quality was investigated for a rural background site in Morogoro. Precipitation, temperature, relative humidity and wind speed were measured during wet and dry seasons of 2005 and 2006 period and their relationship with reported mass of particles of aerodynamic diameter smaller than 10 μm (PM10) for the site was assessed. The results show that higher PM10 mass concentrations (45μg/m 3 ) were obtained during the 2005 dry season and the lowest (13 μg/m 3 ) during the 2006 wet season. It is interpreted that reasons for the higher levels of the particulate matter mass in the dry season are due to temperature inversions and absence of rain washdown. The observed particulate matter levels are also affected by the variations in sources strengths and in meteorological conditions such as mixing height, precipitation, relative humidity, wind speed and direction as supported by air mass trajectories.
Saltwater intrusion in the quaternary aquifer of the Dar es Salaam region, Tanzania
(GEOLOGICA BELGICA, 2012) Mtoni, Yohana; Mjemah, Ibrahimu C.; Msindai, Kristoko; Van Camp, Marc; Walraevens, Kristine
A description of the occurrence of the salt water intrusion from seawater close to the coastline of Dar es Salaam Region is presented. The present status of intrusion in two pilot areas located between Mlalakuwa and Msimbazi Rivers (locality I) and Msimbazi and Kizinga Rivers (locality II) is evaluated. The causes, effects, remedial measures and future possibility of intrusion are discussed. An investigation on the hydrodynamics of the phenomenon and analysis of the formations as well as the interfacial transition zone is currently being performed. Water samples from Mikocheni, Oysterbay, Msasani, Masaki and City Centre areas show elevated chloride, sulphate and sodium concentrations. Using Stuyfzand (1986) water classification method, about 60 percent of the samples are classified as fresh-brackish to salt and 30 percent as extremely hard. Groundwater was classified into several categories by subtype, i.e., Sodium-Chloride, Sodium-Bicarbonate, Calcium-Bicarbonate, Magnesium-Bicarbonate, Sodium-Mix and Calcium-Mix. The growing human population in and around the investigated areas has had an adverse impact on the water in the shallow aquifer through, among other factors, indiscriminate abstraction of water without knowledge of the aquifer’s capacity.
Climate characteristics over southern highlands Tanzania
(Scientific Research, 2012) Mbululo, Yassin; Nyihirani, Fatuma
This study was conducted to examine the climate characteristic of southern highland Tanzania (Latitude 6°S - 12°S and Longitude 29°E - 38°E). The study findings reveal that rainfall over the region is linked with SST over the Indian Ocean, where warmer (cooler) western Indian Ocean is accompanied by high (low) amount of rainfall over Tanzania. During wet (dry) years, weaker (stronger) equatorial westerlies and anticyclone (cyclonic) anomaly over the southern tropics act to reduce (enhance) the export of equatorial moisture away from East Africa. The wettest (driest) season was found to be 1978/79 (1999/00) which can be classified as the severely wet (moderate drought). Two different modes of rainfall have been identified at time scale of 1.5 and 6 years which have been associated with the quasi biennial oscillation (QBO) and El Nino Southern Oscillation (ENSO), respectively.
Climate change impacts and adaptation among coastal and mangrove dependent communities: a case of Bagamoyo district
(2012) Mbwambo, J.S; Madalla, D; Zahabu, E; Ndelolia, D; Mnembuka, B; Lamtane, H. A; Mwandya, A. W
The study was done to determine perception, impacts and adaptation of coastal communities towards climate change. A total of three villages and 120 respondents were involved in the study. Both Focus Group Interviews and a structured questionnaire survey were employed for collection of both qualitative and quantitative data. Content and structural functional analysis was used for qualitative data while descriptive and logistic and regression analysis was employed for quantitative data. Results indicates that majority of the community are involved in both fishing and farming activities for both food and cash income. Results indicates further that majority of the respondents are aware of climate change and they perceive the same in relation to unusual rainfall (87.5%), drought (93.3%), floods (74.1%) and increased incidence of pest and diseases (55.8%). It was also found that farmers are coping with food insecurity as a result of declining food stocks and they have also developed adaptation strategies related to farming operations and livelihoods. However, adaptation varies depending on various farm and household factors and in this income, number of plots, extension services and farm size were highly significant and showed strong positive influence on adaptation to climate change. It is concluded that farmers are aware of climate change and have developed both coping and adaptation strategies against climate hazards. Promotion of extension and enhancement of off-farm activities are recommended for enhancing adaptive capacity of the population in the study area.
Urban climate and bioclimate of Dar es Salaam, Tanzania – preliminary results
(Meteorological Institute, Albert-Ludwigs University Freiburg, Freiburg im Breisgau, Germany, 2012) Ndetto, Emmanuel L; Matzarakis, Andreas
Understanding of the urban climate of a city is important for future planning and human wellbeing. The well known Physiologically Equivalent Temperature (PET) and the Universal Thermal Climate Index (UTCI) indices were calculated with RayMan model using meteorological data (2001-2011) in order to study the human thermal bioclimate of Dar es Salaam. Results indicate that afternoons from late September to May is the heat stressful period. On the other hand, the June-August period is relatively a comfortable time of the year especially the morning hours. These results are however treated as preliminary to the detailed and reliable study that uses hourly datasets and of a long duration.
The role of development projects in strengthening community-based adaptation strategies: the case of Uluguru mountains Agricultural development project (UMADEP)-Morogoro-Tanzania
(International Scholars Journals, 2012) Mussa, Kassim Ramadhani; Mjemah, Ibrahimu Chikira; Malisa, Emmanuel Timothy
This study was trying to find out whether the designing and implementation of the Uluguru Mountain Agricultural Development Project (UMADEP) has taken into account the hazards, impacts and risks associated with climate change and the local coping strategies of their project beneficiaries, since its inception, 17 years ago . Data were gathered using the Community-based Risk Screening–Adaptation and Livelihoods (CRiSTAL) tool, complemented with a series of semi-structured and structured interviews containing both close and open-ended questions. The Vulnerability and Capacity Assessment (VCA) method was also used in identifying resources, capacities and vulnerabilities which pertained to different livelihood settings in the study area. The study found out that coping strategies applied by affected people in the study area vary from one community to the other, depending on level of education, income, household size and agro-ecological zone. Ranking of the identified livelihood resources revealed that natural resources are very crucial in adapting to climate change. Generally, the results indicate a moderate influence of project activities towards enhancing adaptive capacities of the surrounding communities, with the observed positivity of the project activities towards community-based adaptation being more of a coincidence than a planned state-of-affairs. Lack of training to development project officers, managers and planners on the importance of integrating climate change management during the early stages of project development was clearly depicted as a key hindrance to mainstreaming climate change into development planning.
Towards regional, error-bounded landscape carbon storage estimates for data-deficient areas of the world
(PLOS ONE, 2012-09-14) Willcock, Simon; Phillips, Oliver L.; Platts, Philip J; Balmford, Andrew; Burgess, Neil D.; Lovett, Jon C.; Ahrends, Antje; Mbilinyi, Boniface; Lewis, Simon L.
Monitoring landscape carbon storage is critical for supporting and validating climate change mitigation policies. These may be aimed at reducing deforestation and degradation, or increasing terrestrial carbon storage at local, regional and global levels. However, due to data-deficiencies, default global carbon storage values for given land cover types such as ‘lowland tropical forest’ are often used, termed ‘Tier 1 type’ analyses by the Intergovernmental Panel on Climate Change (IPCC). Such estimates may be erroneous when used at regional scales. Furthermore uncertainty assessments are rarely provided leading to estimates of land cover change carbon fluxes of unknown precision which may undermine efforts to properly evaluate land cover policies aimed at altering land cover dynamics. Here, we present a repeatable method to estimate carbon storage values and associated 95% confidence intervals (CI) for all five IPCC carbon pools (aboveground live carbon, litter, coarse woody debris, belowground live carbon and soil carbon) for data-deficient regions, using a combination of existing inventory data and systematic literature searches, weighted to ensure the final values are regionally specific. The method meets the IPCC ‘Tier 2’ reporting standard. We use this method to estimate carbon storage over an area of33.9 million hectares of eastern Tanzania, reporting values for 30 land cover types. We estimate that this area stored 6.33 (5.92–6.74) Pg C in the year 2000. Carbon storage estimates for the same study area extracted from five published Africa-wide or global studies show a mean carbon storage value of ,50% of that reported using our regional values, with four of the five studies reporting lower carbon storage values. This suggests that carbon storage may have been underestimated for this region of Africa. Our study demonstrates the importance of obtaining regionally appropriate carbon storage estimates, and shows how such values can be produced for a relatively low investment.
Modeling approaches and strategies for data-scarce aquifers: example of the Dar es Salaam aquifer in Tanzania
(Springer, 2013) Camp, Marc Van; Mjemah, Ibrahimu Chikira; Farrah, Nawal Al; Walraevens, Kristine
Management of groundwater resources can be improved by using groundwater models to perform risk analyses and to improve development strategies, but a lack of extensive basic data often limits the implementation of sophisticated models. Dar es Salaam in Tanzania is an example of a city where increasing groundwater use in a Pleistocene aquifer is causing groundwater-related problems such as saline intrusion along the coastline, lowering of water-table levels, and contamination of pumping wells. The lack of a water-level monitoring network introduces a problem for basic data collection and model calibration and validation. As a replacement, local watersupply wells were used for measuring groundwater depth, and well-top heights were estimated from a regional digital elevation model to recalculate water depths to hydraulic heads. These were used to draw a regional piezometric map. Hydraulic parameters were estimated from short-time pumping tests in the local wells, but variation in hydraulic conductivity was attributed to uncertainty in well characteristics (information often unavailable) and not to aquifer heterogeneity. A MODFLOW model was calibrated with a homogeneous hydraulic conductivity field and a sensitivity analysis between the conductivity and aquifer recharge showed that average annual recharge will likely be in the range 80–100mm/year.

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