Creating Protected Areas on Public Lands: Is There Room for Additional Conservation?

Area of Science:

• Environmental Science
• Conservation Biology
• Forestry

Background:

• Traditional evaluations of protected areas (PAs) often use indirect comparisons, which can introduce bias if protection isn't randomly assigned.
• Understanding the true impact of PAs on deforestation requires careful selection of control groups that account for differing land characteristics.

Purpose of the Study:

• To assess the impact of Chilean protected areas (PAs) on deforestation between 1986 and 2011.
• To investigate how PA effectiveness estimates change when using different control units, specifically non-protected private versus public lands.

Main Methods:

• Employed matching methods to construct control groups for estimating PA effectiveness, addressing biases from non-random assignment.
• Constructed two distinct control groups: one using non-protected private lands and another using non-protected public lands.
• Analyzed deforestation trends in Chilean PAs and their respective control groups over a 25-year period.

Main Results:

• Chilean PAs demonstrated a significant impact in reducing deforestation when compared against non-protected private lands.
• No significant impact on deforestation was observed when PAs were compared to non-protected public lands.
• Differences in land management regimes and enforcement levels between public and private lands likely influence these varying results.

Conclusions:

• The effectiveness of protected areas in preventing deforestation is contingent on the characteristics of the chosen control group.
• Using non-protected private lands as controls suggests PAs are effective, while using public lands indicates no additional conservation benefit.
• Future research should consider diverse outcomes beyond deforestation, such as forest degradation and biodiversity, and account for varied land management practices.