Climate Change and Ecosystem Services: Decoding the Drivers of Mixed Responses

Redacción HC
21/07/2025

Climate change is widely recognized as one of the greatest threats to human well-being, primarily through its disruption of ecosystem services—the benefits that nature provides, such as clean water, food, climate regulation, and cultural value. Yet, understanding exactly how climate change is affecting these services is far from straightforward. While some impacts are clearly negative, others are unexpectedly positive or show no clear trend at all. This phenomenon of "mixed responses" poses a significant challenge for scientists, policymakers, and environmental managers seeking to adapt to a changing world.

A recent systematic review led by Marcy C. Delos and colleagues from the U.S. Geological Survey’s National Climate Adaptation Science Center, published in PLOS ONE in February 2025, sheds new light on this complexity. The study not only confirms the prevalence of mixed responses in ecosystem services under climate change but also identifies the key factors driving this variability. Understanding these drivers is essential for developing adaptive strategies that are both robust and context-sensitive.

Understanding Mixed Responses in Ecosystem Services

The term "mixed responses" refers to instances where the same ecosystem service responds differently to climate change depending on location, time period, or other variables. For example, agricultural productivity might increase in one region due to longer growing seasons while decreasing elsewhere due to drought stress. Similarly, carbon storage in forests may rise under certain conditions but decline under others, even within the same ecosystem type.

Delos et al. aimed to untangle these inconsistencies by systematically reviewing studies published between December 2014 and March 2018. Unlike previous reviews, such as the one by Runting et al. (2017), this study focused on quantifying the internal variation within individual research outputs, rather than general trends across studies.

Their analysis included 44 peer-reviewed studies that directly assessed the impacts of climate change on the supply, demand, or monetary value of provisioning, regulating, or cultural ecosystem services, as defined by the Millennium Ecosystem Assessment. Importantly, the review applied rigorous inclusion criteria and followed a structured data extraction protocol to ensure consistency and reliability.

Key Findings: The Geography of Research and the Roots of Variability

Research Bias Towards Wealthy Nations

One of the most striking findings was the geographical bias in existing research. Approximately 66% of the ecosystem services evaluated in the reviewed studies pertained to high-income countries. This is concerning because low-income nations are generally more vulnerable to the negative impacts of climate change, yet they remain underrepresented in the research landscape. This gap limits our understanding of global vulnerabilities and hampers the development of equitable adaptation strategies.

The Prevalence of Mixed Responses

Mixed responses were not an anomaly but rather the norm. Around 59% of all observations or projections in the analyzed studies showed mixed outcomes in ecosystem services when exposed to climate change. This underlines a critical insight: when it comes to climate impacts on nature’s benefits, there is no "one size fits all" answer.

The study identifies several factors that contribute to this variability:

• Spatial Variation: The most common driver. Differences in geographic location led to varied responses of the same ecosystem service within a single study area. For instance, water availability may increase in some regions due to higher precipitation while decreasing in others facing intensified drought.
• Scenario Variation: Different climate scenarios, such as high versus low greenhouse gas emissions pathways, also produced divergent outcomes within the same study.
• Temporal Variation: Time periods mattered. A service might respond positively in the short term but negatively over a longer horizon.
• Measurement Metrics: The way services are assessed can itself introduce variation. Different metrics for the same service may yield contrasting results.
• Interactions with Non-Climate Factors: Land use changes, pollution, and other human activities often interact with climate impacts, further complicating the picture.

Crucially, these drivers often operate simultaneously, creating a complex web of interactions that defy simple interpretation.

Practical Implications for Research and Policy

These findings carry significant implications for both research and policy:

• For Researchers: There is an urgent need to design studies capable of detecting and explicitly analyzing variation in responses. Reporting only average impacts risks oversimplifying the situation, potentially misleading decision-makers. Researchers should tailor their methods to the specific decision contexts they aim to inform, ensuring that spatial, temporal, and scenario-based variabilities are all considered.
• For Policymakers and Environmental Managers: Recognizing the reality of mixed responses is critical when crafting adaptation strategies. Policies based on average or generalized projections may fail or even backfire in regions experiencing different or opposite effects. As the authors suggest, disaggregating findings by the identified drivers of variation enhances the relevance and effectiveness of interventions.

Moreover, integrating knowledge of non-climatic factors such as land use or governance systems is essential for a holistic approach to ecosystem management under climate uncertainty.

A Call for More Inclusive and Contextualized Research

The geographic bias towards wealthy nations in climate-ecosystem research underscores a critical blind spot. Developing countries, particularly in Latin America, Africa, and parts of Asia, face unique challenges and vulnerabilities that are not adequately captured by current studies. Increasing research efforts in these regions is not only a matter of scientific completeness but also of social justice and effective policy planning.

Additionally, the study invites a rethinking of research paradigms. Like tailoring clothing to fit diverse body types rather than relying on "one size fits all," ecosystem service assessments must account for local, temporal, and methodological nuances.

Conclusion: Embracing Complexity for Better Adaptation

The complexities unveiled by Delos and her team challenge us to move beyond simplistic narratives about climate change impacts on nature. As we navigate an increasingly uncertain future, embracing this complexity rather than shying away from it can lead to more resilient and equitable environmental policies.

Future research must prioritize filling geographic gaps, refining methodologies to capture variability, and integrating multiple drivers of change. Policymakers, on the other hand, should demand and utilize nuanced, disaggregated data to inform flexible, context-specific adaptation strategies.

Understanding why and how ecosystem services respond differently under climate change is not just an academic exercise—it is essential for sustaining the very benefits that underpin human well-being in a rapidly changing world.

Topics of interest

Climate