Tropical dry forests experience pronounced seasonal changes in precipitation mani-
fested in varied plant phenologies. At landscape scales, geologic substrate—one of the
least understood abiotic factors interacting with precipitation—may modulate phe-
nological responses in these forests through a combination of mechanisms regulat-
ing water and nutrient use. We leveraged a phenological dataset from the semiarid
island of Curaçao to examine the extent to which plant phenology at multiple levels
of biological organization diverge under different geologies. Monthly observations
over a 30-month period of leaves, flowers, and fruits of 69 plant species of different
life forms at three nearby sites differing in their underlaying geology were used to
examine intra- and inter-annual plant responses at species, community, and system
levels. The integration of leaf, flower, and fruit observations at intra-annual scales
revealed diverse phenological strategies among species, broad associations with geo-
logic substrate, and the extent of intra-specific variation as a function of geology. The
community- and system-level analyses at inter-annual scales showed a reduction in
mean leaf scores during the 30-month period, a weak and strong leafless period in
1993 and 1994, respectively, and differences among geologic substrates. Finally, we
observed significant and positive relationships between precipitation and the pheno-
phase scores; the strength of the relationships varied with phenophase and geologic
substrate. Results of this work emphasize the importance of geologic substrate, and
more broadly speaking landscape heterogeneity, in modulating plant phenological re-
sponses in tropical dry forests. Ultimately, this information will become important to
understand and mitigate global climate change impacts.
Abstract in Spanish is available with online material.
tropical dry forests
This discussion paper assesses the state of knowledge on tropical dry forests as it relates to CIFOR’s strategy and identi es research opportunities that align with CIFOR’s strategic goals. Over the past two decades, CIFOR has accumulated a substantial body of work on dry forests, with a particular focus on African dry forests. is paper is intended to build on that work, by gathering wider research from around the world, as CIFOR seeks to widen the geographic scope of its research on dry forests. e present assessment explores ve themes: climate change mitigation and adaptation; food security and livelihoods; demand for energy; sustainable management of dry forests; and policies and institutional support for sustainable management. ese themes emerged as priority areas during discussions on dry forest research priorities held at CIFOR’s Dry Forests Symposium in South Africa in 2011. Research on these themes should be considered a priority, given the importance of dry forests to people and ecosystems around the world and the threats posed to them.
Generally, the review reveals a clear need for an increase in the following:
- Up-to-date information on deforestation in African dry forests
- Livelihoods-based research in Latin America
- Research across the entire portfolio in Asia, the Pacific and the Caribbean.
For specific research topics, the assessment nds the following:
- Research on climate change and carbon is advanced for the dry forests of Latin America and parts of Africa, but severely lacking for other regions.
- Food security and livelihoods have been well studied in parts of Africa, but in all other regions the role of dry forests in food security is under- researched, particularly in the area of direct provisioning.
Africa is well represented in research into energy supply and demand (particularly woodfuel
and charcoal, but increasingly biofuels as well).
- Latin America has been the subject of extensive biofuels research.
- Novel management institutions, such as community forestry, have received research attention in the dry forests of Latin America and Africa but not those of India, where research of this nature has focused on other environments.
- Greater research on sustainable management of dry forests speci cally is required in all regions, as is analysis of forestry policy and policy in other sectors that a ects dry forests.
CIFOR has used recent high-pro le events such as the Dry Forests Symposium in 2011 to build the necessary momentum to put dry forests onto national and international agendas. By prioritizing research that lls knowledge gaps, CIFOR and its partners could strengthen and consolidate its existing work, broaden the available knowledge on dry forests in a relatively short time, and make substantial progress toward achieving its strategic goals, as well as contributing to global policy processes.