The Mediterranean region provides an important setting for studying how soils respond to increasingly dry and warm conditions. Naturally dry soils, low organic matter, and sparse vegetation leave these landscapes particularly vulnerable to erosion, warming, and prolonged drought.
To see how these delicate drylands cope under increasing stress, BIOservicES partners with the Spanish National Research Council (CSIC) to lead field research in the area. Returning to experimental sites in Andorra (Teruel), researchers are studying semi-natural ecosystems to measure how two years of warming and reduced rainfall impact soil biodiversity and long-term land health.
Where did the second soil sampling campaign take place?
The second campaign focused on three semi-natural dryland sites in Andorra, Teruel, Spain, representing different vegetation conditions. The experimental sites consist of one woodland forest and two shrubland systems with different degrees of vegetation cover.
These characteristics make the region particularly relevant for studying soil responses to climate change. Decreasing precipitation and rising temperatures can add further pressure to already dry soil systems, potentially affecting soil moisture, vegetation, and the organisms living below ground.
How was the second sampling campaign carried out?
Researchers returned to the same three sites investigated during the first campaign, allowing the project to compare soil conditions over time.
For the second campaign, sampling was carried out both inside and outside the climate change chambers. The sampling methodology was adapted compared with the first campaign, with a particular focus on causing as little disturbance as possible to soil organisms. According to the team, minimising this disturbance was also the main practical challenge during this year’s fieldwork.
Why return to the same Mediterranean soils?
The first campaign provided an initial picture of the soils and biodiversity present at the study sites. The second campaign adds an important time dimension to the experiment.
This is particularly important for understanding climate change. As the Mediterranean team explains, assessing its impact on soil functioning requires an experimental design based on sampling events conducted at different times. By returning to the same sites, researchers can eventually compare the two datasets and investigate how soils exposed to experimental climate conditions have responded.
As the research team explains:
“The experiment will provide insights into the potential impacts of warming and reduced precipitation on soil functioning and the delivery of ecosystem services.”
Have researchers already observed differences between the two campaigns?
It is still too early to conclude.
During the second sampling campaign, the researchers did not observe any remarkable differences compared with the first campaign. One field observation was that the soil appeared to be less compacted than during the first sampling, but this still needs to be assessed alongside the collected data. Differences in soil moisture will also need to be checked using datalogger measurements.
This is an important distinction from some of the observations made during the first campaign. At that time, researchers were particularly interested in the very low presence of macrofauna across many of the Mediterranean samples, as well as high levels of soil compaction aggravated by arid conditions. These characteristics provide useful context for the second campaign, but further analysis is needed before determining whether or how conditions have changed.
What can the experiment tell us about climate change and Mediterranean soils?
Mediterranean soils already experience conditions of low water availability, making them particularly relevant for studying the potential consequences of warming and reduced precipitation.
Changes in temperature and moisture can affect the conditions available to soil organisms, potentially altering their activity, abundance, and distribution. At the same time, drought and intense rainfall can influence soil structure and erosion, adding further pressure to soil ecosystems.
The first campaign also highlighted the potential importance of soil organic matter and plant diversity for Mediterranean soil biodiversity. Increasing organic matter can improve the conditions available for soil organisms, while greater plant diversity can provide more varied resources and habitats.
By comparing the first and second sampling campaigns, BIOservicES aims to move beyond a single snapshot and investigate how these interconnected components of the soil system respond over time.
What was different about the second campaign?
One advantage during this year’s sampling was the team’s deeper knowledge of both the project and the experimental sites.
During the first campaign, the scale and complexity of the sampling represented a significant challenge. Researchers had to work across different conditions while collecting several types of samples and investigating different components of the soil ecosystem.
Returning to familiar sites meant that the team entered the second campaign with a much stronger understanding of the local conditions and sampling requirements. The researchers identified this accumulated knowledge as one of the most relevant aspects of the second campaign. They noted no major unexpected situations during fieldwork.
What happens to the samples after collection?
Samples were sent to BIOservicES laboratories in Spain, Germany, Italy, and Belgium, reflecting the collaborative effort that involves all project partners and stakeholders.
The analyses involve several project partners: CSIC, UPCT, TUM, WU, and CREA, and are expected to be completed by May 2027, demonstrating ongoing progress and commitment to understanding soil responses.
The analyses will follow the same overall approach as during the first sampling campaign, enabling researchers to compare the two sets of samples and assess potential changes in the soil system.
Who prepared the ground for the Mediterranean sampling campaign?
Our project partner, the Spanish National Research Council (CSIC), prepared the ground for the Mediterranean sampling campaign.
Photo credits: José Ángel Pérez and Jorge Álvaro-Fuentes. Photos taken in Andorra, Teruel (Spain) in May 2026.
This article is part of our Sampling Europe’s Soils series, following the second BIOservicES campaign across the continent. Read our field stories from the Alpine Region and Atlantic Region, and stay connected as our journey continues.
