GlobE-wetlands' Reporting Day

GlobE-wetlands’ Reporting Day

March, the 19th 2018 9:30 - 17:00 Cassava Conference Hall NaCRRI Namulonge

Cover: Drain at the Namulonge Research Station, National Crops Resources Research Institute (NaCRRI), Uganda. Photography by Bernd Diekkr¨ uger.

Recommended Citation: GlobE-wetlands (2018). Reporting Day. NaCCRI-Namulonge, Uganda. 15 pp.

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Program 09:30 10:00 Registration 10:00 10:20 Michael Ugen Androgu. Project Introduction. 10:20 10:40 Godfrey Asea. Welcome Speech 10:40 11:00 Coffee Break 11:00 11:10 Kristina Grotelüschen. Management effects on rice yields: A review of the Namulonge rice trials 2014-2017. 11:10 11:20 Maureen Namugalu. Seasonal effect of Nitrogen source on rice grain yield and Nitrogen uptake across contrasting inland valley positions in Central Uganda. 11:20 11:30 Simon Alibu. Potential of cultivating dry-season maize along a hydrological gradient in an inland valley of Uganda. 11:30 11:35 Discussion 11:35 11:45 Constanze Leemhuis. Modeling impact of land use change scenarios on water resources in a tropical inland valley catchment of central Uganda, East Africa. 11:45 11:55 Claudia Schepp. Slope-valley bottom water and nutrient fluxes in an inland valley wetland in Uganda. 11:55 12:00 Discussion 12:00 12:10 George Aogon. Influences of maize and rice cropping system on productivity and soil carbon flux at different hydrological zones. 12:10 12:20 Björn Glasner. Carbon storage and redox potential variability in experimental fields. 12:20 12:25 Discussion 12:25 14:00 Lunch Break 14:00 14:10 Erick Omwandho Opiyo. Decision support for improving East African wetland use. 14:10 14:15 Benard Nsubuga. Developing experimental ecosystem accounts to analyse environmental change and resources use: A case of the Ugandan Wakiso District. 14:15 14:20 Discussion 14:20 14:30 Matian van Soest. Wetland agriculture and malaria at the urban fringe: Anthropological findings from Namulonge, Uganda. 14:30 14:35 Loum Janani. Governing wetlands: Wetland management, conflict and the role of institutions in Namulonge and Kiwenda, Wakiso District, Uganda. 14:35 14:40 Discussion 14:40 14:55 Coffee Break 14:55 15:05 Kai Behn: Wetland vegetation around Namulonge: Classification and regeneration dynamics. 15:05 15:10 Discussion 15:10 15:40 Discussions in small groups. Future of Ugandan wetlands, tools for sharing project outcomes and potential for implementation. 15:40 16:10 Outcomes of discussions. 16:10 16:40 Foto Contest Award and Farewell.

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Management effects on rice yields: A review of the Namulonge rice trials 2014–2017. Kristina Grotel¨ uschen1* , Susanne Ziegler2 , Matthias Langensiepen1 , Daniel Neuhoff2 , Kalimuthu Senthilkumar3 , Mathias Becker1 1

Institute of Crop Science and Resource Conservation, University of Bonn, Germany. Institute of Organic Agriculture, University of Bonn, Germany. 3 Africa Rice Center, Antananarivo, Madagascar. * [email protected] 2

Rice demand is steadily rising in Uganda and largely exceeding domestic supply. Although it is increasingly appreciated as a cash crop, rice productivity of smallholder farms remains low as a consequence of inadequate management. Compared to uplands, wetlands are particularly suitable for rice production due to favorable edaphic and hydrological conditions. Hence, rice production is progressively shifting into wetland areas which have been only sporadically used in the past. This strategy, however, is environmentally risky as the conversion into farmland may provoke negative effects on the provision of the various ecosystem services. Therefore, field experiments were established to determine attainable yields and analyze effects of various management options on actual grain yield. Using the rice variety NERICA 4, field trials were established at three hydrological positions (drought-prone fringe, middle and flood-prone center) in an inland valley for three consecutive years (2014–2017) at Namulonge, Central Uganda. Management options included water retention (bunds vs. no bunds), weed control and nitrogen (N) management (source and amount). Both attainable and actual yields were largely unaffected by the hydrological position. However, the center position was more prone to seasonal flooding which may constitute a serious production risk. Bunding and repeated weeding increased rice yields significantly from 2.0 t ha-1 to more than 3.0 t ha-1 , with largest benefits in center and fringe position during high to moderate rainfall years. Additional N application further increased yields to 4.0 t ha-1 using a moderate amount of 60 kg Urea-N ha-1 , using the corresponding amount of applied green manure (Lablab purpureus (L.) Sweet) yields increased to 3.9 t ha-1 . Under weed-free conditions, with supplementary irrigation and the application of mineral NPK (120:60:60) yields of 6.0 t ha-1 were obtained and referred to as the attainable yield. We conclude that simple management practices such as field bunding, additional weed control or moderate N fertilization can boost yields considerably beyond current farmers’ yield level (2.0 t ha-1 ). Keywords: Inland valley, Lablab purpureus, NERICA 4, Oryza, Uganda.

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Seasonal effect of Nitrogen source on rice grain yield and Nitrogen uptake across contrasting inland valley positions in Central Uganda. Maureen Namugalu1* , Giregon Olupot1 , Daniel Neuhoff2 , Susanne Ziegler2 1

College of Agriculture, Makerere University, Kapala, Uganda. Institute of Organic Agriculture, University of Bonn, Germany. * [email protected] 2

Inland valleys are targeted for increasing rice production in Uganda but only 10 to 15% of their potential has been tapped into agricultural production. As cultivation expands into inland valleys, effective N management is required to sustain productivity of rice. However, little is known about N management for optimization of rice yields across contrasting hydrological positions. This study was therefore designed to determine the seasonal effect of Nitrogen source on rice grain yield and N uptake across three positions: center, middle and fringe. Consequently, a field experiment was conducted for three long rainy seasons (September to January) in 2014, 2015 and 2016 at Namulonge, Central Uganda. Five treatments were applied: control, 60 kg mineral N ha-1 , 60 kg organic N ha-1 , 120 kg mineral N ha-1 , and 120 kg organic N ha-1 , arranged in a randomized block design with position as a blocking factor. Each treatment was replicated four times. Data was collected on biomass, grain yield and N uptake. We applied ANOVA and Tukey’s HSD for the statistical analysis. There was a significant effect of N source and season on all growth and yield parameters investigated in this study as well as on N uptake. The highest grain yield (7 t ha-1 ) and N uptake (157 kg N ha-1 ) were recorded during the first season in plots that have received 120 kg Urea-N ha-1 . As much as 593 kg cumulative N ha-1 had been taken up by rice by the end of the third season, representing an average uptake of over 90 kg N ha-1 season-1 from the same treatment. This N uptake was 100% above N uptake from control plots and 40% above that from the plots that received 120 kg N ha-1 as organic source. Even without fertiliser application, the amount of N taken up by rice was about 78 kg N ha-1 season-1 . This amount of N must be replenished if productivity of rice is to be sustained in inland valleys. Keywords: Inland valley, mineral N source, N uptake, organic N source, season.

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Potential of cultivating dry-season maize along a hydrological gradient in an inland valley of Uganda. Simon Alibu1,2* , Daniel Neuhoff2 , Kalimuthu Senthilkumar3 , Mathias Becker4 , Ulrich K¨ opke3 1

National Agricultural Research Organization, National Crops Resources Research Institute, Kampala, Uganda. 2 Institute of Organic Agriculture, University of Bonn, Germany. 3 Africa Rice Center, Antananarivo, Madagascar. 1 Institute of Crop Science and Resource Conservation, University of Bonn, Germany. * [email protected].

Maize is the main food staple in East Africa, contributing more than 19% of total calories consumed annually. Shortage of maize will consequently cause food insecurity. Inland-valley wetlands with higher soil moisture than the surrounding uplands provide opportunities for growing off-season maize. We conducted two consecutive field experiments to assess the potential of an inland valley in central Uganda for producing dry-season maize. We evaluated the performance of hybrid maize under different crop-management options at three hydrological positions within an inland valley. Average maize grain yield in the inland valley of 3.8 Mg ha-1 , exceeded the national production average of upland maize by about 60%. The centre position of the inland valley, with higher soil moisture and longer moisture retention than other zones, showed the greatest potential for producing dry-season maize, especially during the short dry season of 2016 when the crop received only 295 mm of rainfall, which represents only half the amount received during the long dry season. Grain yield at the centre position was 50% and 25% higher than the yield at the fringe or middle positions of the inland valley during the long and the short and the long dry seasons, respectively. Availability and farmers’ accessibility of mineral fertilisers is limited, and particularly in rural areas application rates are less than 15 kg N ha-1 . Organic amendments, on the other hand, are widely available, though highly variable in quality. Organic fertiliser application of Lablab purpureus and poultry litter, providing 120 kg N ha-1 produced comparable maize grain and stover yields as the application of 120 kg mineral N ha-1 . However, the application of only 60 kg mineral N ha-1 provided no yield advantage compared to the unfertilized control. Our results suggest that cultivating maize during the dry season in inland-valleys, particularly in the wetter center positions, allows farmers to obtain more harvest, thus contributing to regional food security. Keywords: East Africa, climate change, food security, wetland, Zea mays.

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Modeling impact of land use change scenarios on water resources in a tropical inland valley catchment of central Uganda, East Africa. Geofrey Gabiri1* , Constanze Leemhuis1 . Stephanie Steinbach1 , Frank Thonfeld1 1 *

Bernd Diekkr¨ uger1 , Kristian N¨aschen1 ,

Department of Geography, University of Bonn, Germany. [email protected]

Due to rapid population growth, increasing demand for food, and urbanization in the East African region, the inland valleys have been subject to considerable land use changes into agriculture and settlements. These changes alter the availability of water resources in the inland valley ecosystem. This study investigates the impact of land use change on the hydrological processes in a tropical inland valley catchment. To achieve this objective, an interface based on hydrologial response units (ArcSWAT2012) and a grid-based setup (SWATgrid) of the Soil Water Assessment Tool (SWAT) model are applied to the inland valley catchment of Namulonge, central Uganda. Four land use structure scenarios are established in addition to the current land use system, with different water resources conservation levels (extreme conservation, moderate conservation, conservation of the headwater catchment and exploitation). Satisfactory model performance was achieved from the calibration and validation of daily discharge with values of R2 and NSE higher than 0.5 for both model setups. The annual water balance indicates that 849.5 mm representing 65% of precipitation water is lost via evapotranspiration. Surface runoff (77.9 mm) and lateral flow (86.5 mm) are the highest contributors to stream flow in the catchment. There is a strong relationship between conservation land use scenarios (extreme conservation, moderate conservation, conservation of the headwater catchment), and a decreasing surface runoff, annual discharge and water yield. Exploitation scenario increased annual discharge and water yield due to high peak flows in the catchment. This suggests that the continued poor management of the inland valleys will result in decreased availability of water resources for human consumption and plant growth. This study contributes to improve the scientific knowledge on dynamics of land use impacts on hydrological processes to support sustainable water resources management in inland valleys. Keywords: Land use scenarios, SWAT, water resources, inland valleys.

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Slope-valley bottom water and nutrient fluxes in an inland valley wetland in Uganda. Claudia Schepp1* , Bernd Diekkr¨ uger1 , Mathias Becker2 , Constanze Leemhuis1 1

Department of Geography, University of Bonn, Germany. Institute of Crop Science and Resource Conservation, University of Bonn, Germany. * [email protected] 2

Changing rainfall patterns and recurrent dry spells impose severe challenges on East African rain-fed agricultural communities. Due to their prolonged plant water availability, inland valley wetlands have become increasingly important for food security in the region. Thus a careful and knowledge-based management is crucial for the sustainable cultivation of these fragile ecosystems. In small scale farming, monetary resources for industrial fertilizers are constrained, making Nitrate a limiting factor and efficient management of naturally occurring Nitrogen an essential task for crop development. This study investigates on the temporal and spatial distribution and the relocation of soil born Nitrogen from the slopes to the valley bottom of an inland valley wetland in Uganda. In a plot study the effects of three land use types (bare land, semi-natural vegetation and patchy agriculture) on Nitrogen content in soil and surface water is monitored using ion exchange resins and in situ quantification at different slope positions. Water fluxes from surface runoff and interflow are quantified on runoff plots and in excavations at the bottom of the slope. Soil moisture is measured using a PR2 soil moisture probe. Geoeletrical measurements have been conducted to investigate underground structures and water pathways. Nevertheless, water pathways in the soil are not yet fully understood. Nitrogen content in soil water and soil moisture vary between the three land use types with highest concentrations found on the bare plots. A sandy loam layer at the bottom of the slope is delivering water and nitrate to the wetland even during dry season. The flowrate depends on the frequency and intensity of rainfall events and the nitrate concentration in the interflow reflects the influence of the different land use types. Nitrate concentrations in soil water at the fringe of the wetland though were found to be very low. Thus down slope positions before the fringe seem to be of special importance if nitrate was to be put into production before being lost for plants from the wetland due to anaerobic soil conditions. Keywords: Nitrate, interflow, wetlands, Uganda.

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Influences of maize and rice cropping system on productivity and soil Carbon flux at different hydrological zones George Aogon1,2* , John Steven Tenywa1 , Nicolas Br¨ uggemann3 , Katrin Wagner3 1

College of Agriculture, Makerere University, Kapala, Uganda. National Crops Resources Research Institute, Kampala, Uganda. 3 Institute of Bio- and Geosciences, Forschungszentrum J¨ ulich, Germany. * [email protected] 2

Maize and rice are among the most important food crops in the world. Their productivity may be nevertheless constrained by drough stress due to climate change, meanwhile wetlands are becoming important areas of cultivation. The consequent intensification of use for crop production is threatening wetlands functioning as carbon sequesters. Field experiments were established to determine crop effects on soil CO2 emissions under different management options. Such options included weed control and Nitrogen supply either from inorganic N, organic N, zero N supply and common farmers’ practices. NERICA 4 and LONGE 10H were used as test varieties for rice and maize, respectively. Field trials were established at three hydrological zones, namely fringe, middle and flooded centre at Namulonge, Central Uganda. The experimental plots were established and cultivated from 2015 until 2017. In both varieties the yield was highest with inorganic N supply (5.5 t ha-1 in rice and 6.0 t ha-1 in maize), and lowest under common farmers’ practices 1.6 t ha-1 and 1.5 t ha-1 . The“grain:soil flux ratio”in both maize and rice reduced along the slope across all treatments during the wetter production periods in 2016 and 2015, respectively. It however increased along the slope in maize during the drier periods, this trend was similar in rice, where there was an increase from dry zone to wet zone (middle). Nevertheless, as conditions became inundated there was a reduction. In both crops, grain:soil flux ratio from inorganic N was higher than in further management practices. We therefore conclude that complementary rice and maize production is possible using inorganic N under moderate soil moisture conditions in the fringe and middle zones. Keywords: Soil CO2 emissions, cropping system, agronomic system.

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Carbon storage and redox potential variability in experimental fields. Bj¨ orn Glasner1* , Sabine Fiedler1 1 *

Geographical Institute, University of Mainz, Germany. [email protected]

As a result of soil degradation in the uplands and population growth, the importance of wetland soils for agricultural production will increase during the next decades in East Africa. Nevertheless, little is known about organic matter (OM) dynamics in these soils, though OM is crucial for soil fertility and represents an important carbon sink. We aimed to investigate OM and redox-potential (Eh) dynamics along a topographical gradient in the bottom area of a small inland-valley in Namulonge, Uganda, by assessing the redox-potential, organic carbon (OC) stocks, quantity of particulate and mineral-associated OM, and stabilization agents of OM. Therefore, we installed Platinum electrodes for continuous measurements of the Eh in three positions (fringe, middle, and riparian), applied a twofold density separation of the OM of the bulk soil to determine the quantity of free particulate OM (LF), occluded particulate OM (oPOM), and mineral-associated OM (Min-OM), and determined iron(hydr-)oxide fractions. Our hypotheses were that (i) along the topographical gradient we have an Eh gradient, (ii) the OC stocks increase along the Eh gradient, and (iii) the proportion of LF is larger in more wet areas (lower Eh) compared to dryer areas (higher Eh). Against our hypotheses, we did not find any correspondence between Eh gradient and topographic position. The middle position shows the lowest Eh, followed by the riparian and the fringe had the highest Eh. Along this increasing Eh gradient we find increasing OC stocks. This is due to really low portions of LF and oPOM in the soils and an increasing iron(hydr-)oxide content of the soil with increasing Eh. Theses iron(hydr-)oxides are stabilization agents of OM but with lower Eh values these iron(hydr-)oxides become more soluble. Keywords: Density separation, particulate organic matter, mineral-associated organic matter, iron(hydr-)oxides.

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Decision support for improving East African wetland use. Erick Omwandho Opiyo1* , Matthias Langensiepen1 1 *

University of Bonn, Institute of Crop Science and Resource Conservation, Germany. [email protected]

Decision makers in environment agencies and institutions have relied on science based decision support systems (DSS) for information on possible choices, alternatives and preferences to perceived environment problems in complex systems, and policy formulation. The resulting decision could have varying degree of risks and consequences. Therefore the information presented should be in a form that surmises what has been collected and analyzed without putting too much cognitive load on the decision makers. In the East Africa wetlands project, data on social, economic and environmental state of wetlands was collected from field surveys, observations and experiments and modeled against future scenarios. Through participatory assessment workshops with engaged stakeholders, various wetlands scenarios are weighted in order to come up with decision alternatives. Delivering this information through DST requires a system design approach, that utilizes best practices of decision making analysis, software engineering and interaction design. This means that the resultant tool should be intuitive to use and informative to enables decision makers get various decision alternatives and test them against environmental, economic and social scenarios and at the same time use the tool at various sites, while allowing for regional upscaling. Various decision making methods have been developed over the decades that analyzes best ways of coming up with optimum alternatives given certain criteria. Multi-criteria decision making (MCDM) is one of the proposed method that will be used in this project, because of its ability to rank decision alternatives derived from both qualitative and quantitative data sources. There is a general consensus that preferred decision making methods are the ones that involve decision makers and other stakeholders at every stage of decision making process and decision tool development. Keywords: Decision support systems, decision support tools, multi-criteria decision making.

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Developing experimental ecosystem accounts to analyse environmental change and resources use: A case of the Ugandan Wakiso District. Benard Nsubuga1* , Lars Hein1 , Fanou Landry1 1 *

Wageningen University and Research Centre, the Netherlands. [email protected]

Despite their importance in the provisioning of services for human being, ecosystems are rapidly degraded worldwide. The limited attention to generation of integrated information on ecosystems and ecosystem-economy relationships in the national accounting systems, has become a major hindrance to sustainable ecosystem management. To address this information gap, we examined the applicability of the System of Environmental Economic Accounting-Experimental Ecosystem Accounting (SEEA-EEA) approach at the Ugandan Wakiso District, by developing experimental ecosystem account to analyse and monitor environmental change and resources use. The ecosystem extent, condition and service supply, were emphasized as they are springboards for comprehensive ecosystem accounting. Forests, wetlands, and farmlands were selected for this purpose. The district’s geospatial information and further statistics were the major primary data sources for this study. Ecosystem accounts were developed for periods of: 1990–2005, 2005–2010, and 2010–2015. The study’s outcomes indicated degrading ecosystems in all accounting periods. Well stocked and low stocked tropical forests had the highest extent loss of 78% and 53% respectively within the 1990–2005 accounting period. Converting natural ecosystem to managed ecosystems including farmlands and settlements was the major contributing factor. Declining rain-use efficiency was observed in all accounting periods, where wetlands reduced the most (i.e. 3 Kg C mm-1 yr-1 between 2005 and 2010). Total average carbon sequestration reduced with declining ecosystem extent. Farmland ecosystem indicated the lowest per hectare carbon sequestration (between 0 and 2 ton C ha-1 yr-1 ), and tropical forests the highest (13 tonnes C ha-1 yr-1 ). Food provision increased when farmland wetlands decreased over the years. Stakeholders recommended to aggregate ecosystem accounting information from micro- to macro-levels, with a strong focus on experimental and survey studies. Overall, our study illustrated the relevance of SEEA-EEA approach through providing sequential integrated ecosystem information. Hence, the outcomes create a baseline for future ecosystem accounting studies in Uganda. Keywords: Ecosystem accounting, environmental changes, sustainable ecosystem use.

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Wetland agriculture and malaria at the urban fringe: Anthropological findings from Namulonge, Uganda. Matian van Soest1* 1 *

Department of Social and Cultural Anthropology, University of Cologne, Germany. [email protected]

The current land dynamics and rising land-prices in the proximity of town, drive smallholders whose livelihood often depends directly on agriculture, into wetlands for income-generating activities. Agriculturally used wetlands provide ideal breeding grounds for mosquitoes, which in turn transmit malaria parasites to humans. Wetlands thus play an ambivalent role in the distribution of malaria, as they provide an income to people, needed to access malaria treatment, while at the same time expose them to malarial parasites. When looking at the local perception of malaria, a considerable discrepancy with the biomedical understanding of the disease is noticeable. Malaria is not perceived as a major health-threat and thus treatment is often delayed in order to avoid costs. Medicinal plants and other alternative medicines are often used as cheaper options, especially in children, and biomedical care is frequently consulted too late. Moreover, medical pluralism and the popularization of biomedical knowledge lead to the use of “malaria” as an umbrella term for a range of feverish ailments. These findings show that the local understanding of malaria as a generic feverish disease, can lead to the application of problematic self-medication. Malaria, and its treatment are to a great deal depending on financial means. While many people depend on wetlands to gain an income, these ecosystems also expose them to the threat of a malaria infection. With the ongoing population growth and the associated urban expansion in Uganda and elsewhere in sub-Saharan Africa, the exploitation of wetlands is likely to further increase and expose a larger number of people to malaria. In order to target malaria and its treatment, it is required to incorporate the local understandings of the disease, and place it in an socio-economic and ecological context. Keywords: Malaria, medical anthropology, health seeking, wetland agriculture, political ecology of health.

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Governing Wetlands: Wetland management, conflict and the role of institutions in Namulonge and Kiwenda, Wakiso District, Uganda. Loum Janani1* , Lioba Lenhart1 , Clemens Greiner2 1

Institute of Peace and Strategic Studies, Gulu University, Uganda. Global South Study Centre, University of Cologne, Germany. * [email protected] 2

Despite national legislation and policies for wetland conservation, management and sustainable use are provided, conflicts over wetlands between government, wetland users from the adjacent communities and investors have remained widespread. The aims of this study are 1) to ascertain the diversity of resources available to the people living in the vicinity of Namulonge and Kiwenda wetlands, Wakiso District, Central Uganda, as well as patterns of resource use and environmental awareness of users; 2) to establish the institutions, rules and organisations governing in the area; and 3) to examinate conflicts and approaches to conflict resolution. Qualitative data was collected through participant observation, semi-structured interviews, focus group discussions and transect walks. The purposively selected respondents included local people relying on wetlands as a source of their income and livelihoods, environmental professionals engaged in the management of wetlands, NGO and CBO representatives; as well as stakeholders at various levels of local government. Our findings reveal that wetlands users in Namulomge and Kiwenda depended on wetland resources and products for securing their livelihoods, including water supply, clay, mats, timber and firewood, fish and vegetables. However, awareness about overuse of resources leading to resource depletion and national policies for wetland protection is not properly raised. This was partly caused by lack of effective wetland management structures at sub-county level, where there was no environmental focal officer responsible for wetland issues and no community involvement in wetland management. It was not possible to ascertain any severe conflicts over wetlands in the study site. However, there was tension between the National Crops Resources Research Institute (NaCRRI) and the wetland users from Kiwenda who accused the Institute for having introduced caterpillars for research purposes without controlling them so that they migrated to the farms of wetland users. In conclusion, much as Uganda recognizes the importance of wetland management, less than 5% of its citizens understand the policies regulating wetland activities. We therefore recommend rigorous sensitization on wetland policies and provision of incentives to operate in wetland areas. Keywords: Wetland Management, diversity of wetland resources, conflict.

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Wetland vegetation around Namulonge: Classification and regeneration dynamics. Kai Behn1* , Samuel Mutebi2 , Miguel Alvarez1 1

Institute of Crop Science and Resource Conservation, University of Bonn, Germany. Department of Botany, Makerere University, Uganda. * [email protected] 2

Wetlands are important habitats for plant and animal species and provide several ecosystem services. However, wetlands in East Africa are subject to degradation, often resulting from drainage and land use intensification. For sustainable management strategies and conservation plans, it is crucial to understand structures and dynamics of wetlands. Plant communities reflect ecological conditions and degrees of disturbances and may hence be used as bio-indicators. Consequently this work aims at classification of wetland vegetation and the analysis of succession processes. We sampled vegetation in around 400 plots in the Namulonge valley in Uganda as well as in the Kilombero floodplain in Tanzania marking plots of 4 m2 . Both study sites are dominated by cultivation of rice and other crops, while natural vegetation and long term fallows also occur. Plots were chosen along gradients of hydrology and land use intensity. Additionally, we did a repeated sampling of plots after induced disturbance in an experimental set up. Plots were classified according to composition and dominance of species into plant communities using the supervised classification approach of the Cocktail classification. Formal definitions of plant communities were developed and compiled to an expert system. Additionally, we analyzed changes in changes in species composition and biomass over time in the experimental plots. In total, we defined eleven plant communities of which six occurred in the Namulonge valley. There was no overlap between the study sites. Beside their species composition, the plant communities also differed regarding predominant life forms. Results from the succession experiment show a periodical increase of biomass and gradual turnover of plant species. The approach of formal definitions for plant communities enables an easier comparison of the vegetation between different study sites. Keywords: Cocktail classification, expert system, inland valley, plant community, succession.

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Notes:

The “GlobE-wetlands Photo Contest” was organized in the context of the Reporting Day. Pictures displaying not only interesting aspects of the project activities but also funny moments were submitted for this competition. During the reporting day, winners of the GlobE-wetlands Photo Contest will be awarded. Take a look at the Photo Gallery:

The GlobE-wetlands (https://www.wetlands-africa.uni-bonn.de) is an initiative coordinated by the University of Bonn in Germany and implemented in collaboration with several institutions in Germany, the Netherlands, Uganda, Rwanda, Kenya and Tanzania. The aim of the project was to assess the importance of East African wetlands for food security in the region and the effects of land uses on the integrity of the wetlands’ agro-ecosystems. The project employed a cross-scale multi-disciplinary research approach involving agronomy, ecology, hydrology, geography, health and human sciences. Ugandan partners in the project are Makerere University and NaCRRI, while some other institutions have also supported in specific activities. Organization: Michael Ugen Androgu, Simon Alibu, Claudia Schepp, and Miguel Alvarez.