28 research outputs found
Predicted land use and land cover outlook for semi-arid Lokere and Lokok catchments in Karamoja region, Uganda
The semi-arid Lokere and Lokok catchments in northeastern Uganda are
experiencing land use and land cover (LULC) change driven by policies
and actions aimed at pastoralist sedentarisation. While these efforts
present a trajectory of a landscape dominated by farming, livestock
herding or grazing persists. The objective of this study was to project
medium, and long-term LULC for Lokere and Lokok catchments in Karamoja,
Uganda. We applied automatic multi-perceptron neural network, built on
Markov chain modeling method, along with multi-criteria evaluation
strategies; all embedded in the IDRISI Land Change Modeler (LCM) to
project the catchments\u2019 LULC to the year 2030 and 2050. The model
was trained using 1994 and 2003 LULC, and validated with 2013 LULC.
Results of three modelled policy scenarios; business as usual (BAU),
pro-livestock and pro-farming; to the years 2030 and 2050 showed that
small scale farming (SSF) would increase in all scenarios, even if
policy shifts to promote livestock rearing. Pro-farming policies would,
in both 2030 and 2050, result in reduction of grassland as SSF
increases; doubling the 2003 land area by 2050. The results of this
study facilitate assessment of potential impacts of the future LULC and
policy evaluation in the catchments.Les bassins versants semi-arides de Lokere et de Lokok dans le nord-est
de l\u2019Ouganda connaissent un changement d\u2019utilisation des
terres et de couverture terrestre (UTCT) motiv\ue9 par des politiques
et des actions visant la s\ue9dentarisation des pasteurs. Si ces
efforts pr\ue9sentent une trajectoire d\u2019un paysage domin\ue9
par l\u2019agriculture, l\u2019\ue9levage ou le p\ue2turage
persiste. L\u2019objectif de cette \ue9tude \ue9tait de projeter
une UTCT \ue0 moyen et long terme pour les bassins versants de Lokere
et Lokok \ue0 Karamoja, en Ouganda. Nous avons appliqu\ue9 un
r\ue9seau neuronal multi-perception automatique, construit sur la
m\ue9thode de mod\ue9lisation de cha\ueene de Markov, ainsi que
des strat\ue9gies d\u2019\ue9valuation multicrit\ue8res; tous
int\ue9gr\ue9s dans le mod\ue8le IDRISI Land Change Modeler (LCM)
pour projeter le UTCT des bassins versants jusqu\u2019en 2030 et 2050.
Le mod\ue8le a \ue9t\ue9 form\ue9 \ue0 l\u2019aide de 1994
et 2003 UTCT, et valid\ue9 avec UTCT de 2013. R\ue9sultats de trois
sc\ue9narios de politique mod\ue9lis\ue9s; business as usual
(BAU), pro-b\ue9tail et pro-agriculture; a montr\ue9 que
l\u2019agriculture \ue0 petite \ue9chelle (SSF) augmenterait dans
tous les sc\ue9narios, m\ueame si les politiques changeaient pour
promouvoir l\u2019\ue9levage pour les ann\ue9es 2030 et 2050. Des
politiques favorables \ue0 l\u2019agriculture entra\ueeneraient,
en 2030 et 2050, une r\ue9duction des prairies \ue0 mesure que les
champs de culture augmentent; doubler sa superficie de 2003 d\u2019ici
2050. Les r\ue9sultats de cette \ue9tude facilitent
l\u2019\ue9valuation des impacts potentiels de UTCT future et
l\u2019\ue9valuation des politiques dans les bassins versants
VEGETATION BIOMASS PREDICTION IN THE CATTLE CORRIDOR OF UGANDA
Pastoralists in Sub-Saharan Africa face complex problems notably
frequent and severe droughts. This study was conducted in the cattle
corridor of Uganda, a largely semiarid area to estimate the likely
vegetative biomass production under the 2O71-2100 projected rainfall
conditions. Spatio-temporal pattern of vegetative biomass production
were determined by analysis of the seasonal variation of Normalised
Difference Vegetation Index (NDVI) for 10 years from 2001-2010. A
biomass relationship was established between the NDVI and the
Standardised Precipitation Index (SPI); and used to project the period
2071-2100 NDVI using downscaled rainfall for the cattle corridor. A
change trajectory performed on the annual means revealed the highest
increase in vegetation in 2008 (0.031) and decrease in 2009 (-0.022).
The SPI revealed two main droughts that were established to have
occurred in the years of 2004 - 2005 and 2008-2009. The wettest year
was 2003 and corresponded with the increase in NDVI. A strong positive
correlation of rainfall and vegetation was established (r=0.99).
Precipitation has influenced vegetative biomass in the cattle corridor
as there is a positive correlation between precipitation and the
vegetative biomass production. Secondly, vegetation is likely to be
concentrated in areas that will have high precipitation in 2070-2100,
such as Luwero and the districts south of it of the cattle corridor
compared to those in the north of the cattle corridor of Uganda.Les \ue9leveurs en Afrique Sub-saharienne se confrontent aux
probl\ue8mes complexes notamment les s\ue9cheresses fr\ue9quentes
et plus graves. Cette \ue9tude a \ue9t\ue9 men\ue9e dans le
corridor du b\ue9tail de l\u2019ouganda, une r\ue9gion largement
semi-aride pour estimer la production susceptible de biomasse
v\ue9g\ue9tale sous les conditions pluviom\ue9triques
projet\ue9es en 2071-2100. Le mod\ue8le spatio-temporel de
production de biomasse v\ue9g\ue9tale a \ue9t\ue9
d\ue9termin\ue9 par l\u2019analyse de la variation
saisonni\ue8re de l\u2019Indice de V\ue9g\ue9tation par
Diff\ue9rence Normalis\ue9e (NDVI) pendant 10 ans dans
l\u2019intervalle de temps 2001-2010. Une relation de biomasse a
\ue9t\ue9 \ue9tablie entre l\u2019indice de v\ue9g\ue9tation
NDVI et l\u2019indice de pr\ue9cipitations normalis\ue9 (SPI), et
elle est utilis\ue9e pour projeter le NDVI de la p\ue9riode
2071-2100 en utilisant les pr\ue9cipitations \ue0 \ue9chelle
r\ue9duite pour le corridor du b\ue9tail. Une trajectoire de
changement effectu\ue9e sur les moyennes annuelles a
r\ue9v\ue9l\ue9 la plus forte augmentation de la
v\ue9g\ue9tation en 2008 (0.031) et une diminution en 2009
(-0.022). Le SPI a r\ue9v\ue9l\ue9 deux principales
s\ue9cheresses qui ont \ue9t\ue9 \ue9tablies pour avoir eu lieu
dans les ann\ue9es 2004 - 2005 et 2008-2009. L\u2019ann\ue9e la
plus humide \ue9tait 2OO3 et correspondait \ue0 une augmentation de
l\u2019indice de v\ue9g\ue9tation NDVI. Une forte corr\ue9lation
positive entre les pr\ue9cipitations et la v\ue9g\ue9tation a
\ue9t\ue9 \ue9tablie (r = 0.99). Les pr\ue9cipitations ont
influenc\ue9 la biomasse v\ue9g\ue9tale dans le corridor du
b\ue9tail, car il existe une corr\ue9lation positive entre les
pr\ue9cipitations et la production de la biomasse v\ue9g\ue9tale.
Deuxi\ue8mement, la v\ue9g\ue9tation est susceptible
d\u2019\ueatre concentr\ue9e dans les zones qui auront de fortes
pr\ue9cipitations en 2070-2100, comme Luwero et les districts du Sud
de celui-ci du corridor du b\ue9tail par rapport \ue0 ceux dans le
nord du corridor du b\ue9tail de l\u2019ouganda
REGIONAL CLIMATE MODEL PERFORMANCE AND PREDICTION oF SEASONAL RAINFALL AND SURFACE TEMPERATURE oF UGANDA
Knowledge about future climate provides valuable insights into how the
challenges posed by climate change and variability can be addressed.
This study assessed the skill of the United Kingdom (UK) Regional
Climate Model (RCM) PRECIS (Providing REgional Climates for Impacts
Studies) in simulating rainfall and temperature over Uganda and also
assess future impacts of climate when forced by an ensemble of two
Global Climate Models (GCMs) for the period 2070-2100. Results show
that the models captured fairly well the large scale flow signals
influencing rainfall and temperature patterns over Uganda. Rainfall and
temperature patterns were better resolved by the RCM than the GCMs. The
rainfall and temperature patterns differed among the three seasons.
Rainy season March to May (MAM) is likely to experience increment in
both surface temperature (0.9\ub0 C) and rainfall (0.2 mm day-1). For
September to october (SON) rainy season, an opposite trend in the two
climate parameters, temperature and rainfall, will be registered with
the former increasing by 0.9 \ub0C and the latter dropping by 0.7 mm
day-1. For the dry season, June to August (JJA), both temperature and
rainfall are projected to decrease by 0.3 \ub0 C and 0.4 mm day-1,
respectively.La connaissance du climat de demain fournit un aper\ue7u sur la
mani\ue8re dont les d\ue9fis pos\ue9s peuvent \ueatre
adress\ue9s. Cette \ue9tude a \ue9valu\ue9 la comp\ue9tence
du Mod\ue8le Climatique R\ue9gional (RCM) PRECIS du Royaume Uni
(fournissant des climats r\ue9gionaux pour des \ue9tudes
d\u2019impacts) dans la simulation de la pluviom\ue9trie et la
temp\ue9rature en ouganda et, d\u2019autre part, \ue9tudier les
impacts des climats une fois forc\ue9e par un ensemble de deux
Mod\ue8les Climatiques \ue0 l\u2019\ue9chelle de l\u2019Univers
(GCMs) pour les p\ue9riodes 2070-2100. Les r\ue9sultats montrent
que les mod\ue8les ont raisonnablement saisi une large \ue9chelle
du flow des signaux qui influencent la tendance de la pluviom\ue9trie
et la temp\ue9rature en ouganda. Les tendances de la
pluviom\ue9trie et la temp\ue9rature \ue9taient mieux
d\ue9termin\ue9es par RCM que GCMs. Les tendances de la
pluviom\ue9trie et la temp\ue9rature diff\ue9raient au cours des
trois saisons. La saison pluvieuse Mars \ue0 Mai (MAM) connaitra
probablement une augmentation de la temp\ue9rature (0.9 \ub0C) et
de la pluviom\ue9trie (0.2 mm jr-1). Pour la saison de pluie de
Septembre \ue0 octobre, une tendance contraire dans les deux
param\ue8tres climatiques sera enregistr\ue9e avec la m\ueame
augmentation de 0.9 \ub0C et une diminution de 0.7 mm jr-1de pluie.
Pour la saison s\ue8che de Juin \ue0 Ao\ufbt (JJA), les
projections montrent une diminution de la temp\ue9rature et de la
pluie de 0.3 \ub0C et 0.4 mm jr-1, respectivement
LAND USE/COVER CHANGE PATTERNS IN HIGHLAND ECOSYSTEMS OF LAKE BUNYONYI CATCHMENT IN WESTERN UGANDA
Land use and cover changes influence the livelihood and degradation of
fragile ecosystems. The extents of these changes in pattern were
investigated in Lake Bunyonyi Catchment which lies in the South Western
Highlands of Uganda. The dynamics and magnitude of land use and cover
changes were assessed using Landsat (TM/ETM+) satellite images and
collection of socio-economic data through interviews. The images were
processed and analysed using the mean-shift image segmentation
algorithm to cluster and quantify the land use and cover features. The
study noted that in the assessment period 1987-2014, the small-scale
farmlands, open water and grasslands remained quasi constant; while the
woodlots followed a quadratic trend, with the lowest acreage
experienced in 2000. The tropical high forests and wetlands cover types
experienced significant decline over the years (P<0.05). Patches of
small-scale farmlands, woodlots, and wetland interchangeably lost or
gained more land dependant on climate variability. Even though the
tropical high forest lost more than it gained, it only gained and lost
to small scale farmland and woodlots; while grassland mainly lost to
small scale farmland and woodlots.L\u2019occupation du sol et les changements de couverture influencent
la subsistance et la d\ue9gradation des \ue9cosyst\ue8mes
fragiles. La tendance des niveaux de ces changements \ue9taient
\ue9valu\ue9e dans le basin versant du lac Bunyonyi qui relie les
r\ue9gions montagneuses du Sud-Ouest d\u2019Ouganda. Les dynamiques
et l\u2019 envergure d\u2019utilisaton de la terre et les changements
de couverture \ue9taient \ue9valu\ue9es en utilisant les images
du satellite Landsat (TM/ETM+) et la collecte des donn\ue9es
socio-\ue9conomiques \ue0 travers des interviews. Les images
\ue9taient trait\ue9es et analy\ue9es en utilisant
l\u2019algorithme de segmentation de passage-moyen-d\u2019image pour
grouper et quantifier les occupations du sol et les
caract\ue9ristiques de la couverture. L\u2019\ue9tude a
montr\ue9 que dans la p\ue9riode d\u2019\ue9valuation de
1987-2014, la petite \ue9tendue de terres cultivables, l\u2019eau
libre et les prairies sont demeur\ue9es quasi constantes; tandis que
les terres bois\ue9es ont suivi une tendance quadratique, avec la
plus petite superficie observ\ue9e en l\u2019an 2000. Les grandes
for\ueats tropicales et les zones humides ont exp\ue9riment\ue9
un d\ue9clin significatif au cours des ann\ue9es (P<0.05). Les
petites parcelles de terres agricoles, les terres bois\ue9es, et les
zones humides indistinctement ont perdu et gagn\ue9 plus de terres
d\ue9pendamment de la variabilit\ue9 climatique. Bien que la grande
for\ueat tropicale aie perdu plus qu\u2019elle en a gagn\ue9e;
elle a seulement perdu de tr\ue8s petites \ue9tendues de terres
agricoles et bois\ue9es; alors que les prairies ont principalement
perdu de tr\ue8s petites \ue9tendues de terres agricoles et
bois\ue9es
The Effect of Land Cover Change on Soil Properties around Kibale National Park in South Western Uganda
The change from natural forest cover to tea and Eucalyptus is rampant in protected areas of western Uganda. The objectives were; to examine the trend in land-use /cover change and determine the effect of these changes on the physico-chemical properties of soils around Kibale National Park. The trend in land use/cover change was assessed by analyzing a series of landsat images. Focused group discussions and key informant interviews were used for land-use/cover reconstruction. Three major land uses were included; woodlot (Eucalyptus grandis; 5 years old) ), tea (57 years old) and natural forest used as a control. Each of these land-uses were selected at two different North facing landscape positions and were replicated three times. A total of 36 composite soil samples were taken at 0–15 and 15–30 cm depth from natural forest, Tea plantation and eucalyptus on three ridges. Results showed that small scale farming, tea and eucalyptus plantation and built up area have increased over time, to the expense of woodlot and forest cover. Tea and Eucalyptus have induced changes in: exchangeable Mg and Ca, available P, SOM, pH, and bulk density of sub soil (P<.05). Landscape positions within land use also significantly influenced most soil properties (P<.05). Similar findings were observed by Wang et al. (2006) in commercial tea plantations in China that received nitrogen fertilizers
Multilingual global e-learning pediatric endocrinology and diabetes curriculum for front line health care providers in resource-limited countries: Development study
Background: Electronic learning (e-learning) is a widely accessible, low-cost option for learning remotely in various settings that allows interaction between an instructor and a learner. Objective: We describe the development of a free and globally accessible multilingual e-learning module that provides education material on topics in pediatric endocrinology and diabetes and that is intended for first-line physicians and health workers but also trainees or medical specialists in resource-limited countries. Methods: As complements to concise chapters, interactive vignettes were constructed, exemplifying clinical issues and pitfalls, with specific attention to the 3 levels of medical health care in resource-limited countries. The module is part of a large e-learning portal, ESPE e-learning, which is based on ILIAS (Integriertes Lern-, Informations-und Arbeitskooperations-System), an open-source web-based learning management system. Following a review by global experts, the content was translated by native French, Spanish, Swahili, and Chinese-speaking colleagues into their respective languages using a commercial web-base
Water use efficiency of maize (Zea mays L.) crop under selected soil and water conservation practices along the slope gradient in Ruzizi watershed, eastern D.R. Congo
Open Access Journal; Published online: 18 Oct 2022Maize (Zea mays L.) productivity is constrained by water shortages in the predominantly rainfed agriculture of the tropical semi-arid Ruzizi Plain, in the eastern Democratic Republic of Congo (DRC). The region is characterized by a high seasonal and inter-annual rainfall variability and a frequent occurrence of consecutive dry days within growing seasons. Consequently, planning water utilization in rainfed agriculture has become complex, as appropriate soil water conservation (SWC) practices are lacking among most smallholder farmers. Identifying practices that increase water use efficiency (WUE) along the slope gradient is crucial for supporting maize production in the region. In this study, we assessed, for three growing seasons, the effectiveness of two SWC practices (tied ridges and Zai pits) in improving the WUE of two maize varieties along three slope gradients (0–2, 2–8, and 8–15%) in the tropical semi-arid Ruzizi Plain. In this area, rainfall amounts (142–289 mm) were consistently below the evapotranspiration demands (356–533 mm) across the three growing seasons. Tied ridges recorded the highest grain yield (2.16 t ha−1) and WUE (15.23 kg mm−1), especially at low slopes, when compared to Zai pits and conventional tillage. For all SWC practices, WUE decreased with the slope gradient (p < 0.01). Furthermore, a decrease in stored soil water (SWS) at silking and maturity stages (milk, dough, and dent stages) negatively affected the WUE. The variety had no significant effect on grain yield and WUE. Root biomass (RBM), shoot biomass (SBM), and leaf area index (LAI) at the flowering stage were the most associated with the WUE (R2 = 58.5%). In conclusion, tied ridges showed potential for improving maize WUE and yield in the water-deficient conditions that characterize the Ruzizi Plain, and could be promoted to improve the maize productivity among smallholder farmers
Characterization of Historical Seasonal and Annual Rainfall and Temperature Trends in Selected Climatological Homogenous Rainfall Zones of Uganda
There is general lack of scientific consensus on the trend and distribution of annual and
seasonal rainfall and temperature in Uganda. This study used both observational and AgMerra
rainfall and temperature data for the period 1980-2010 to characterize the trend and variability in
seasonal and annual rainfall, maximum and minimum temperatures across 12 different rainfall
homogenous zones (K, H, ME, L, J, F, MW, D, E, A1, A2, and I) of Uganda. Trends analysis was
done using regression method, while coefficient of variation and ANOVA techniques were used
to analyze variability. The results show statistically significant increasing trends (P ≤ 0.05) in
annual rainfall amount in zone A1 and a declining trend for zone K (P<0.05)