Plant Diversity and Distributions
Patterns of Plant Diversity and Distribution


CCSD is advancing the understanding of patterns of plant diversity and distribution through studies that integrate plant occurrence data accumulated by Garden botanists over many years with other types of information such as phylogenies and geographic environmental data. These studies revolve around two broad themes. 

  • The description of spatial and temporal patterns of plant diversity and distribution, including patterns of species richness, rarity, and turnover (beta-diversity). These patterns determine the ways in which limited resources for the conservation of biodiversity should be distributed to accomplish or maximize conservation goals, such as protecting a given set of taxa (or, following other biodiversity metrics, protecting phylogenetic diversity).


  • The investigation of the ecological and evolutionary processes underlying spatial and temporal patterns of plant diversity and distribution. Conserving biodiversity implies conserving biological processes responsible for biodiversity patterns. Awareness of those processes is essential for their conservation and management.


          Changes in diversity and species turnover across elevations in the Madidi region

Assessments of the Conservation Status of Plant Species


CCSD is conducting a species-by-species conservation analysis of the entire flora of Nicaragua. The Garden’s publication of a complete, modern Flora of the country in 2001, with an associated database of more than 120,000 records that includes most of the plant specimens ever collected in Nicaragua, gave the country an unprecedented opportunity to evaluate and act on the conservation of its diverse flora. In carrying out the analysis, CCSD scientists are using the database to identify candidate species for conservation, evaluate the present distribution of these species with respect to currently protected areas, and make recommendations for their preservation. After identifying the species of greatest conservation concern using the IUCN Red List Categories and Criteria, they are studying the species that fall within the IUCN threat categories on the ground, one by one. The most critically endangered species will be considered for ex situ conservation.

Collaboration to explore the responses of biomes and their constituent species to climate change in Andean South America

CCSD scientists Iván Jiménez and Adam Smith are collaborating with Tiina Sarkinen and James Richardson of the Royal Botanic Garden Edinburgh (RBGE) in a project entitled Species-level biome response to climate change in Andean South America under a grant awarded to RBGE by the Royal Society of London, the national Academy of science in the UK. The grant, part of the Society’s effort to stimulate new collaborations between UK scientists and leading scientists overseas, supports a travel exchange that aims to build a collaborative research program in biome ecology and evolution between RBGE and MBG. The RBGE and MBG teams will bring complementary expertise in plant phylogenetics, biome evolution (RBGE), floristics, and spatial modeling (MBG) to the program.

The two-year exchange will address a key issue for conservation: the assumption that biomes—complex ecological communities composed of thousands of plant species—will respond to climate change as simple units, and the increasing evidence that plants will react to climate changes individually and in varied ways, leading to the formation of ecosystems that do not occur at present. The project will explore the potential responses of biomes and their constituent species to climate change in Andean South America and will quantify the large variation among species’ responses. It will also examine the ways in which changes in diversity patterns might affect the capacity of biomes to provide valuable ecosystem services such as water supply, nutrient cycling, food provision, and crop pollination. The project findings will be vital to managing sustainable development and use of natural resources in the coming decades. Andean South America was selected as the project’s focus because the region has exceptionally high plant diversity that is thought to be particularly threatened by global climate change, yet very little is known about plant responses to climate change in the tropical Andes.

The collaborating scientists will use specimen data from the herbaria at MBG and RBGE to estimate species’ current environmental and spatial distributions and to model their responses to potential future climatic conditions. In doing so, they will consider whether species with different functional traits (e.g., leaf length, leaf area, wood density) and life history traits (e.g., annual, perennial) will respond to climate change differently or in a similar manner. Using DNA sequencing, the project will also measure the ways in which plants have responded to climate change that occurred in the past, model the evolution of their ecological traits, and then determine whether they have the capacity to adapt to environments likely to occur in the future.