BIODIVERSITY ASSESSMENT FOR THREE MPIKA WETLANDS OF THE SAB PROJECT A study commissioned by Wetland Action Conducted by Moses A. Nyirenda (BSc, MSc), October 2008 The SAB project is a demonstration project of the Wetlands and Poverty Reduction Project of Wetlands International and it is carried out with financial support from Wetlands International under its Wetlands and Poverty Reduction Project financed by the Dutch Ministry of Foreign Affairs (DGIS). ACKNOWLEDGEMENTS Many people have assisted in this work. In particular I would like to thank Mr. Sam Simwinga and Humphrey Munyenyembe who participated in the risky work with long walks in the three dambos as we collected GPS coordinates using the first principles in land survey. The project staff, Jonas Sampa and Ernest Cheepa, deserve my thanks as well. I am particularly thankful to the Community Development Facilitators in the three dambos who participated in the field work. My many thanks go to the community members, the users of the dambos , who freely took time off from their busy schedules to share their history, experiences and knowledge with the study team for two consecutive days in each of the dambos. Their information was so valuable in compiling this report. Lastly, I would like to thank the University of Zambia, Biology Department for the identification of some of the grass species. Moses Amos Nyirenda October 2008 1 Table of Contents ACKNOWLEDGEMENTS............................................................................................................................ 1 TABLE OF CONTENTS............................................................................................................................... 2 CHAPTER 1. INTRODUCTION AND STUDY OBJECTIVES.............................................................................. 3 1.1 Introduction................................................................................................................................... 3 1.2 Study objectives............................................................................................................................. 4 CHAPTER 2. STUDY METHODS ................................................................................................................. 5 2.1 Establish spatial extent of the study sites....................................................................................... 5 2.2 Establish the vegetation communities and their spatial extent and distribution in each of the three sites.. ................................................................................................................................... 5 2.1 Extent and type of agricultural activities in the dambos and biodiversity loss threats assessment .......................................................................................................................................... 5 CHAPTER 3. KEY FINDINGS AND DISCUSSION. .......................................................................................... 6 3.1 Spatial extents of the three pilot sites............................................................................................ 6 3.2. Biodiversity assessment and spatial distribution of main plant communities.................................7 CHAPTER 4 CONCLUSIONS..................................................................................................................... 22 CHAPTER 5. RECOMMENDATIONS......................................................................................................... 23 REFERENCES. ..................................................................................................................................... 24 2 CHAPTER 1. INTRODUCTION AND STUDY OBJECTIVES 1.1 Introduction . Wetlands are areas that are either periodically wet or permanently flooded with a water layer not exceeding three meters in depth. Wetlands include swamps, flood plains and dambos and exclude open waters that are several meters deep. Wetlands cover 150,520 km 2 of Zambia’s land representing 20% of the total land area of 752,600 km 2.(Mukanda, 1994) A dambo is defined as a seasonally waterlogged, low lying, gently sloping, treeless, grassland depression, with a water table in the upper 50-200cm of the soil profile which is drained by a stream. According to Ferreira, (1981), dambos cover 35,000 km 2 or 4.6% of the national area. Verboom, (1968), classified Zambian dambos as sweet, sour or intermediate depending on their pH as summarized in the table below. Sweet dambos Intermediate dambos Sour dambos Ph Range ≥7, have basic parent material 5.5-6.5 ≤5.5, dambos developed on peaty or sandy soils Characteristic vegetation Grasses : Acroceras macrum, Echinochloa Mixture of Sweet and Sour dambo Variety of Sedges, Hyparrhenia pyramidalis, Setaria spp., and Hemarthria species bracteata, Aristida atroviolacea altissima and Trachypogon spicatus. Desmodium salicifolium Only few sedges found Legumes: Teramnus gillettii, Alysicarpus rugosus, Acacia spp Spatial distribution Parts of Northern, Western, Copper belt and Central , Eastern parts of Zambia Mostly in the Northern half of the Southern Zambia country Adapted from Verboon, 1981 - Due to availability of moisture for the most parts of the year, dambos represent ecologically important areas with high biodiversity where natural ecological processes occur. Because of the foregoing, dambos offers a wide range of livelihood opportunities such as crop production, livestock grazing, wildlife production, fishing, gathering of wild food products, gathering of grass for multiple uses, collecting of medicinal plants, brick making, sand quarrying and indeed they are sources of domestic and industrial water throughout the year. However, despite being very rich and stable ecological units, dambos easily become threatened habitats if they are mismanaged due to over-cultivation, excessive/ wrong methods of digging drains to reclaim more land for cultivation, overgrazing, cutting of riverine vegetation, sand quarrying and overuse of chemical fertilizers and pesticides. These factors can lead, and have lead, to the drying of dambos . Although farmers have traditionally used dambos for crop production in Zambia, the intensity and level of dambo utilization has increased in the last 15-20 years due to a combination of population growth, occurrence of droughts, and the need for income generating opportunities. 3 The Striking a Balance (SAB) project is a project of Wetland Action and Self Help Africa, funded by Wetlands International . The project aims at striking a balance between wetland ( dambo ) utilization for the creation of socio-economic benefits and the maintenance of the ecological functioning of the dambos in order to fill the seasonal food and income gaps. The project is being piloted in three dambos areas (namely Mushishe, Mwansabamba and Chikakala-Chiboni) of Mpika District of the Northern Province of Zambia. Fig 1: Position of Mpika in Zambia 1.2 Study objectives This study was commissioned in order to establish the baseline biodiversity situation – identifying the main grass and plant communities in the three pilot wetlands. It also sought to establish the perceived threats to biodiversity loss at plant community level due to cultivation. Specifically the study aimed to establish: a) The main plant communities characterizing each of the three pilot areas and the broad distribution of these communities across the three sites, b) The extent to which each of the dambo areas has been converted to agriculture, and the community perception of the dangers identified with increased crop production in each of the areas. c) The extent to which there have been changes in wetland biodiversity as a result of agricultural and livelihood development and to identify increases and decreases in major elements of plant biodiversity, especially species of economic interest , including, but not only restricted to, the edible orchids, called Chikanda, in the three sites. 4 CHAPTER 2. STUDY METHODS 2.1 Establish spatial extent of the study sites. In the absence of detailed satellite vegetation maps for the study area due to the smallness of the scale, the spatial extent of the three wetlands were established by recording the GPS tracks along the edges of the dambos and tracks along the streams draining each of the three dambos by using a hand held Garmin GPS76 . The data was presented as map outputs and shapes files for use as baseline information. 2.2 Establish the vegetation communities and their spatial extent and distribution in each of the three sites The main vegetation communities both across the transverse section and the longitudinal extents in each of the three dambos were assessed by setting transverse transects at 500m intervals and studying the main plant communities in 5x5m quadrants set at every 200m along the transects. The local key informants helped in the identification of the main plant communities and in interpreting the relationship between the occurrence of plant communities and the water regime in the dambo , as well as the succession / sequence after cultivation. GPS coordinates for the main plant communities were recorded using a hand held Garmin GPS unit and the data processed using ArcMap 9.2 software. Using the software, the main plant communities were connected in the longitudinal section to obtain the spatial distribution of the main communities both across and along the dambo . A total of 75 grass, sedge and herbaceous species samples were submitted to the University of