Research Questions





Restoration Decisions: (and theory)


reference sites

Case Studies


State of the Science

success criteria
floristic quality


Created by:

Abby Rokosch
Jessen Book
Siobhan Fennessy
This table is reprinted from (Ehrenfeld and Toth, 1997) consists of a list of research questions in ecosystems ecology that are important in restoration ecology. The authors divided the questions into two groups: (1) those that are immediately and directly relevant to the planning and evaluation restorations and (2) those that are more general to ecosystems ecology but have implications for restoration practices.

Immediately Relevant Questions

(1) What features of ecosystem boundaries promote or prevent transfers between adjacent systems?
(2) Is restoration promoted by relatively "open" or "closed" boundaries?
(3) Is there a critical (i.e., minimum) area for particular types of ecosystem below which self-sustaining units cannot be described?
(4) How are descriptors of ecosystem function such as NPP and nutrient cycling rates related to the openness of boundaries (for example, does productivity within a given ecosystem increase as the rate of exchange with adjoining ecosystems increase?)?
(5) How does the scale of the restoration affect the importance of disturbance operating a both smaller and greater scales?
(6) How can the concept of "functional groups" be used in restoration? For example, can restoration be enhanced by identifying important functional groups in a target system, and then ensuring the presence of representatives of each system?
(7) Are there ecosystem-level indicators of the likelihood that a system will be susceptible to invasive species? Which of the ecosystem descriptors, or what set of descriptors, can best be used to estimate invasibility?
(8) How do the input, quality, and dynamics of detrius change over successional time, and how do they react to restoration efforts?
(9) How do above-ground successional changes affect below-ground food webs and process rates, and vice-versa? More broadly, can below-ground food webs be manipulated by changing above-ground vegetation?

General Ecosystem Questions Relevant to Restoration

(1) Do changes in the fluxes of energy and materials across boundaries over time drive temporal changes in other ecosystem descriptors?
(2) How do internal dynamics- material cycling, production, respiration- change with successional time?
(3) How do individual species affect ecosystem properties? Conversely, how sensitive are different ecosystem properties to changes in species diversity?
(4) Are there general principles that can be developed to recognize "keystone" species?
(5) How do differences in net primary productivity affect food web architecture and species diversity?
(6) What is the range of ecosystem values over which individual ecosystem descriptors vary for particular ecosystems? Are some ecosystem descriptors intrinsically more or less variable? Are some types of ecosystems intrinsically more or less variable than are other types for many descriptors?