Forest colonization of savannas : patterns and process

Includes abstract.Includes bibliographical references (leaves 95-102).In this study, I explored factors that influence forest colonization in a South African savanna. I used a 50 year fire experiment in the Kruger National Park to explore patterns of forest colonization in a mesic Terminalia sericea savanna. I studied woody seedling and sapling distribution in relation to different burning treatments, including no burning, and microsite position - in the open or under the canopy of tall trees. The study showed that species richness and abundance was greatest under Sclerocarya birrea, low under Terminalia sericea and lowest in the open habitats. Low fire frequency increased species richness and abundance under S. biirea, but not under T. sericea or the open habitats. Fire sensitive or fire-intolerant species were highest under tree canopies on unburnt and triennial burn plots, whereas frequently burnt (annual or biennial) plots, had fire tolerant and typical savanna species. Frequent burning reduced woody plant biomass by killing seedlings, saplings and adult trees. Fire exclusion led to a higher seedling and sapling recruitment under S. birrea and T. sericea than open habitats

A global assessment of policy tools to support climate adaptation

Governments, businesses, and civil society organizations have diverse policy tools to incentivize adaptation. Policy tools can shape the type and extent of adaptation, and therefore, function either as barriers or enablers for reducing risk and vulnerability. Using data from a systematic review of academic literature on global adaptation responses to climate change (n = 1549 peer-reviewed articles), we categorize the types of policy tools used to shape climate adaptation. We apply qualitative and quantitative analyses to assess the contexts where particular tools are used, along with equity implications for groups targeted by the tools, and the tools’ relationships with transformational adaptation indicators such as the depth, scope, and speed of adaptation. We find diverse types of tools documented across sectors and geographic regions. We also identify a mismatch between the tools that consider equity and those that yield more transformational adaptations. Direct regulations, plans, and capacity building are associated with higher depth and scope of adaptation (thus transformational adaptation), while economic instruments, information provisioning, and networks are not; the latter tools, however, are more likely to target marginalized groups in their design and implementation. We identify multiple research gaps, including a need to assess instrument mixes rather than single tools and to assess adaptations that result from policy implementation

A systematic global stocktake of evidence on human adaptation to climate change

Assessing global progress on human adaptation to climate change is an urgent priority. Although the literature on adaptation to climate change is rapidly expanding, little is known about the actual extent of implementation. We systematically screened >48,000 articles using machine learning methods and a global network of 126 researchers. Our synthesis of the resulting 1,682 articles presents a systematic and comprehensive global stocktake of implemented human adaptation to climate change. Documented adaptations were largely fragmented, local and incremental, with limited evidence of transformational adaptation and negligible evidence of risk reduction outcomes. We identify eight priorities for global adaptation research: assess the effectiveness of adaptation responses, enhance the understanding of limits to adaptation, enable individuals and civil society to adapt, include missing places, scholars and scholarship, understand private sector responses, improve methods for synthesizing different forms of evidence, assess the adaptation at different temperature thresholds, and improve the inclusion of timescale and the dynamics of responses