MAGNITUDES FÍSICAS Y ANÁLISIS DIMENSIONAL.

Seven main land use categories were separated using supervised classification. Settlement and urban areas increased five-fold between 2003 and 2008 while all other land use type either increased or reduced marginally or remained the same (Figure 2 and 3). There was an increase in farmlands between 1986 and 2003 coupled with a slight decrease in both forest cover and urban areas and settlements. Farmlands increased between 1986 and 2003, but reduced between 2003 and 2008.

Geoffrey M. Wambugu and Simon Onywere

Figure 2: Major land use types in the coast of Kwale District between 1986 and 2008

The rapid replacement of farmland by urban areas and settlement has been attributed to an increasing human population. For example, in the Kwale County, the human population increased from 496,133 in 1999 to 607,752 in 2010 (KNBS, 2011). As human population increases, more areas are developed, gradually replacing farmlands. This is because farm areas are available to be converted to settlement and urban areas compared to other forms of land use, such as protected forests, mangroove areas and beach. As more areas are converted to settlements, fewer areas are available for cultivation, which will compromise the area’s food security. Previous attempts to rank forest pressures in East Africa’s coastal forests (e.g. WWF-EARPO 2002; GEF, 2002) identified the main forest pressures as agriculture, settlement and urbanization, lack of legal protection and human-wildlife conflicts as the most serious threats to East Africa’s coastal forests. The root causes of these threats were identified as population growth, poverty, inefficient land use practices, limited effectiveness of forest management regimes among others.

Farmlands become increasingly unavailable due to settlements development, leading to channeling of human population pressure to the next available option (forests and mangrove areas). Tourism development can improve the socioeconomic situation of the area, especially ecotourism, since image analysis reveals an overall increase of forest areas between 1986 and 2003. Forested areas can be developed to encourage the use of non consumptive forest products, such as ecotourism. This will encourage the sustainable use of forest resources.

Land-Use Dynamics as Drivers of Degenerating Community-Based Forest Management Systems in the Kenyan Coast

Environmental Issues and Sustainable Development

165 Figure 3: Land-use classification composites from Idrisi showing changing land-uses in three time period (1986, 2003 and 2008). Note the rapid replacement of farmlands (orange) into settlement areas (grey) between 1986

and 2008). 3.2 Effectiveness of Forest Management Systems

Government managed forests recorded overall gains in forest cover of 135.2ha between 1986 and 2003 and by 622.9ha between 2003 and 2008. In contrast, forest cover in community-managed forests declined 142.9ha and 9.6ha for the same periods, respectively.

Geoffrey M. Wambugu and Simon Onywere

Table 2: Forest area gains and losses (in hectares) amongst the 12 forests used in the analysis

Forests 1986-2003 2003-2008 Shimoni 75.62047 -127.117 Marenji -20.225 43.5366 Mrima Hill 50.0346 3.41145 Dzombo Hill -11.4527 49.22235 Buda -12.6711 294.0345 Gongoni 53.9334 359.8268 Kaya Kinondo -6.1731 0.081225 Kaya Mtswakara -96.1704 64.6551 Kaya Ngandini -22.9055 -12.4274 Kaya Teleza -4.38615 1.6245 Kaya Lunguma -28.1039 -56.2077 Kaya Muhaka 15.5952 -7.31025

Between 1986 and 2003, three of the six government managed forests sampled increased or retained forest cover; Shimoni 75.6ha, Mrima Hill 50.0ha, and Gongoni 53.9ha (Figure 4, Table 2). The rest lost cover between the same period (Marenji 20.2ha, Dzombo Hill 11.4ha and Buda Forest 12.6ha). However, between 2003 and 2008, only one of the forests in the government category lost cover (Shimoni forest; 127.1ha).

The differences between gains and losses in forest cover were used to compare mean forest losses (and gains) across management regimes and temporal periods. Forest gains and losses were significant between temporal periods (1986-2003; 2003-2008); as well as between management regimes (government vs. community), where community forests (t, 22 =-1.22, p=0.05; t, 22 =1.87, p=0.05).

Figure 4: Forest areas in government category in three temporal periods showing an overall increase in forest cover between 1986 and 2008

Community managed forests lost between 4.3ha (Kaya Teleza) and 96.2ha (Kaya Mtswakara) between 1986 and 2003 (Figure 5, Table 2). Gains were recorded at Kaya Muhaka only (15.6ha). Between 2003 and 2008, half of the community managed forests lost cover while the rest gained or retained cover (Figure 5).

Land-Use Dynamics as Drivers of Degenerating Community-Based Forest Management Systems in the Kenyan Coast

Environmental Issues and Sustainable Development

167 Figure 5: Forest areas in community category in three temporal periods showing a general loss in forest cover

between 1986 and 2008

Our results show that government-managed forests are more effective in maintaining forest cover. Similar results were shown by Ngari (2007), who used Management Effectiveness Scores to assess the effectiveness of management options in eastern Arc and coastal forests of Kenya. The study revealed that state owned forests had higher Management effectiveness scores (48%) compared to community-managed forests (27%). Community-based forest management strategies should be entrenched into the law so that they are recognized as a legal entity. The inscription of Kaya forests into the list of Natural World Heritage Sites (UNESCO, 2008) is a major step towards recognition of traditional forest management strategies as valid forest management systems. Acknowledgements

The study was supported by a grant from the Critical Ecosystem Partnership Fund through Nature Kenya and Birdlife International. We also thank staff at the Regional Centre for Mapping of Resources for invaluable help in image data acquisition and image analysis. We are grateful to the staff of Kenyatta University for their invaluable assistance during development of the manuscript.

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Mapping Distribution and Habitat Suitability –An Example of the European