Evaluating Vulnerability and Response of Mangrove Ecosystem to Climate Variability and Change in Lamu County, Kenya

Abstract

Globally, the extent and evolution of risks to the mangrove ecosystem from climate hazards largely remain a major concern. This is particularly so for the island communities whose adaptive capacity in the face of such risks remains grossly limited despite the many interventions to address this growing vulnerability and risks from climate to mangrove ecosystem. The objectives of this study were three: first, to map land cover land use changes for the mangrove ecosystem over the past 25 years; second, to explore the potential risks from climate hazards to households’ livelihoods, health and well-being, biodiversity, and assets and investments in Lamu’s Pate Island and Kiunga-Mkokoni; and third, to co-develop locally-driven adaptation strategies that also address the potential risks from the current interventions, by examining the latter’s fit-for-purpose, potential of nature-based solutions (NbS) to address climate risks, and any missed opportunities for adaptation. The study adopted remote sensing techniques in mapping and detecting land use – land changes (LULC) and both scientific and indigenous or live experiences to evaluate the impacts of and associated risks from climate change. Participatory approaches were used to explore and co-develop adaptation strategies and possible co-benefits to people, nature, and the local economy. In the period 1997 – 2007, the Pate area experienced a net loss in the mangrove area of up to -9.0424 % compared to -5.7597 % for the Kiunga – Mkokoni area. However, the loss in the Pate area reduced to -3.34923 % between 2017 and 2022 but with a much higher loss of up to -24. 14 % in Kiunga - Mkokoni. As an indicator of mangrove recession, the area covered by sand and mud has increased at an annual rate of 4.289 % for Pate and 3.182 % for Kiunga-Mkokoni. Overall, mangroves in the Pate area have recorded a decline of up to - 4.1754 % in the last 25 years while Kiunga-Mkokoni has experienced a mangrove gain of up to +2.0231 % over the same period. There has also been an increasing trend in the minimum and maximum temperatures for Lamu in the last 30 years. The January-February-March (JFM) season experienced an average Standard Precipitation Index (SPI) value of -2, implying drier than average conditions between 1999–2019. The study revealed a recurring early onset of kaskazi or dry season, notwithstanding, the duration and severity of impact that have only become more pronounced over these years. This was sustained at -1.5 SPI value and unusually prolonged beyond March. The current average annual mangrove loss of 2.751 % for Lamu is higher than the 0.15 % yearly loss rate reported for 2010 – 2016. The observed mangrove dieback, particularly in Pate Island, presents dynamic risks to the people in terms of multidimensional poverty and starvation, emerging diseases, biodiversity loss, and potential loss of cultural artifacts, critical assets, and investments. In terms of responses, nearly 64% of the respondents strongly believe that the current interventions to help address risks from climate change also have benefits to reducing emissions from deforestation and forest degradation plus forest-related activities that protect the climate (REDD+). However, about 69 % of the respondents strongly believe that there is a serious lack of climate resilience mainstreaming in the specific activities under the current interventions, with risks from maladaptation higher in areas with multiple actors. There is also 44% confidence among the respondents on the potential of NbS approaches to address risks related to the impacts of climate change in Lamu. This study recommended deliberate and inclusive capacity development in technical training, adaptation finance, information, data and awareness, and practical technology options. There is also a need to foster strategic partnerships and collaborations in climate literacy and conservation programs. Fundamentally, it is imperative to mainstream and fund trans-disciplinary research for better climate adaptation policy outcomes.