Problems and Opportunities of Wetland Management in Rwanda
Total Page:16
File Type:pdf, Size:1020Kb
Problems and opportunities of wetland management in Rwanda Nsharwasi Léon Nabahungu Thesis committee Thesis supervisor Prof. dr. ir. L. Stroosnijder Professor of Land Degradation and Development Wageningen University Thesis co-supervisor Dr. S. M. Visser Teamleader, Alterra, Wageningen UR Other members Prof. dr. H.H.T. Prins, Wageningen University Prof. dr. K.E. Giller, Wageningen University Dr. ir. G.E. Halsema, Wageningen University Dr. B. Vanlauwe, CIAT-Nairobi TSBF, Kenya This research was conducted under the auspices of Graduate School: C.T. de Wit Production Ecology and Resource Conservation Problems and opportunities of wetland management in Rwanda Nsharwasi Léon Nabahungu Thesis submitted in fulfilment of the requirements for the degree of doctor at Wageningen University by the authority of the Rector Magnificus Prof. dr. M.J. Kropff, in the presence of the Thesis Committee appointed by the Academic Board to be defended in public on Tuesday 10 April, 2012 at 4 p.m. in the Aula. Nsharwasi Léon Nabahungu Problems and opportunities of wetland management in Rwanda, 134 pages. Thesis Wageningen University, the Netherlands (2012) With references, with summaries in English and Dutch ISBN 978-90-8585-924-6 Financially supported by Netherlands Fellowship Programme (NFP) Land Degradation & Development (LDD) Group of Wageningen University Acknowledgements The completion of this work has been possible through the assistance and co-operation of several people and institutions. I am grateful to Netherlands Fellowship Programme (NFP), the Land Degradation & Development (LDD) Group of Wageningen University and CIALCA for the PhD sandwich fellowship, which allowed me to stay in Wageningen and to support my field and laboratory activities. A special thanks to my promoter Prof. Dr. ir. Leo Stroosnijder (Chair of Land Degradation and Development Group) who accepted me as a PhD student and assisted throughout this thesis. Many thanks to my daily supervisor Dr. Saskia M. Visser; your comments, field trips to Rwanda, moral support, encouragement and stimulating discussions have guided me all over the current thesis. I am deeply indebted to my supervisor in Rwanda Dr. Bernard Vanlauwe. Thanks for your scientific guidance during on-farm experiments and papers writing in spite of your many other duties. To Dr. J.G Mowo, World Agroforestry Centre coordinator of Eastern African region, thanks for your contribution to improve the quality of this dissertation. I am very grateful to the entire academic, technical and administrative staff members and PhD students of the LDD group. I really enjoyed the lovely working environment and nice social events with them, all of which I can never forget. My special words of thanks go to Dirk Meindertsma and Marnella van der Tol for organizing my repeated travels to and from Wageningen and arranging for my accommodation. I would like to express my gratitude to my home institute ISAR for selecting me as candidate for PhD studies and for granting me time to do the research. I wish to thank my colleagues at Ruhande station, all of them have contributed to this work in one way or another. Special thanks go to Kabiligi Michel, Ngenzi Guy and Mbanda Jocelyne for excellent field work and survey. I am highly indebted to all of you who assisted our family when my lovely Vestine was very sick. Clemence, Bernadet, Yvettes, Desiree and others, I cannot forget the nights passed at the hospital without sleeping for caring my wife and many friends and relatives to comfort us during this dark period. I thank you indeed. To my friend family Anecto Kayitare for your advices and regularly visiting my family while I stayed away or when Vestine had health problems. I would also like to express my most sincere gratitude to my elder sister Judith M., her husband Janssen T. and their family for the love they gave to me. Janssen, your love and encouragement to undertake further studies have made me a good scientist. Please accept my sincere appreciation. I am highly indebted to my Mum, C. Nyiramutumwa who showed me parental love and installed in me values of dignity, hard work and honesty. To my father, L. Ntikanga for his continued reassurance and fatherly love. Finally, I wish to express my sincere indebtedness to my lovely wife, V. Mukashema, and my kids R. Shema, C. Ishimwe, L. Hirwa and L. Teta for approving doing my PhD by foregoing the right to be cared by a husband and father. It is a delight for me to dedicate this work to them. Table of Contents Chapter 1 Introduction 1 Chapter 2 Wetlands in Rwanda: typology, functions, problems and opportunities 17 Chapter 3 Farmers’ knowledge and perception of agricultural wetland management 35 In Rwanda Chapter 4 Contribution of wetland agriculture to farmer’s livelihood in Rwanda 51 Chapter 5 Nutrient resources flows in agricultural wetland and hillside fields in 67 Rwanda, as affected by farmer’s resource endowments Chapter 6 Improved agricultural productivity of wetlands through fertilizer use 85 and N fixation enhancement Chapter 7 Synthesis 101 References 111 Summary 123 Samenvatting 127 PE&RC PhD Education Certificate 131 Curriculum vitae and author’s publications 133 Chapter 1 Introduction Introduction Rwanda is currently suffering from tremendous pressure on agricultural land due to the rapid demographic growth and the limited availability of productive land. The rural population density has grown from 121 persons km-2 in the 60’s, to 262 in 1990, and to 380 persons km-2 in 2010 (National Statistics Institute of Rwanda, 2007). Considering that 90% of the working population in Rwanda is employed in agriculture, the per capita availability of agricultural land has declined over the decades from 3 ha per household in the 1960’s to less than 1 ha per household at present (Verdoodt and van Ranst, 2006). The increasing population pressure on available land and water resources has led to their degradation, and resulted in the loss of productivity of arable lands and increased food insecurity (Bidogeza et al., 2009). Due to soil erosion processes and limited fertilizer use, the productivity of the small agricultural plots is no longer sufficient to provide food security for the majority of poor farmers (Ansoms and McKay, 2010). The response of Rwanda’s farmers to the pressure on land and associated decline in productivity has been to expand their agricultural activities into the fragile wetlands. The total area of wetlands in Rwanda is approximately 278,000 ha of which, in 2009, 53% was used for cultivation. This accounts for 12% of the total cultivated land in the country (REMA, 2009). In Rwanda "wetland" means all lowland and comprises all valley bottoms, both the well-drained and wet parts. In the past wetlands in Rwanda have been used in many different ways and in the future they have a great role to play in the national economy. Understanding the problems and opportunities regarding management of this valuable resource is vital to their long term productivity and is the focus of this thesis. At present wetlands support the livelihoods of many poor people through agriculture providing both food and income. Most Rwandan farmers practice subsistence farming. Farmers living in the uplands make use of the neighbouring wetlands and generally plant similar crops in both up- and lowlands, except for paddy farming which is cultivated only in wetlands (Ngarambe and Kanyarukiga, 1998). In the wetlands of Rwanda, rainfed agriculture is performed in the dry areas, and groundwater dependent agriculture is practiced in the wet areas. Traditionally, farmed wetlands are simple, require low budget inputs, and cover small areas. Generally, yields in the wetlands are higher compared to yields in uplands. This is due to the continuous availability of water and the relatively higher fertility of wetlands. The farming system and the level of organisation of farmers that cultivate the wetlands differ with the level of wetland reclamation (MINAGRI, 2002). The traditionally reclaimed wetlands are either individually or family managed, and farmers select their own crops. Sometimes, informal groups are formed in which farmers help each other with agricultural tasks in both the wetland and upland fields. At the other end of the spectrum is the situation where crops and cropping systems are selected through consensus by a management committee. The Rwandan government considers wetlands as an important resource for the intensification of agriculture, which is required to achieve the goals of food security and poverty reduction as targeted in the agricultural policy of May 2000. According to the National Poverty Reduction Programme of the Ministry of Finance and Economic Planning, for Rwanda to achieve an overall GDP growth rate of 6.4%, agriculture should grow at 5.3%. It further estimates that improved wetland management has the potential to contribute to this growth by 0.5%. Therefore, the Rwandan government supports “wetland development” with the aim of boosting agricultural production, revitalizing the rural economy and reducing poverty (Kanyarukiga and Ngarambe, 1998). 3 1.1 Problem description The government of Rwanda is keen to see that the wetlands, considered to be islands of food production, continue to play a key role in agricultural development and has allocated a substantial share of resources to their reclamation and management (Kanyarukiga and Ngarambe, 1998). Traditional management of Rwandan wetlands is based on the local knowledge of hydrology, soils and vegetation that has been gained over decades of working and observation. These practices, developed by communities, are mainly aimed at meeting the immediate needs of food and cash income with little or no consideration to their environmental consequences. Traditional systems often remain rather small scale and therefore the impact on the availability of environmental services is rather low. Large-scale new reclamations, however, have shown a number of problems. 1.1.1 Lack of awareness and recognition of the multi-functionality of wetlands at all levels Wetland areas reclaimed by public services or under the framework of a broad project are generally large and complex and may have far reaching environmental consequences.