Understanding the complex relationship between ecosystem functions and services still requires improving models and combining approaches
By Paula Drummond
Ecosystems carry out natural processes that support life on the planet and provide direct or indirect benefits for human well-being, such as food production and climate regulation. Ecosystem functions are the natural activities and processes organisms and ecosystems perform, such as nutrient cycling, photosynthesis, soil formation, and pollination. Ecosystem services are the direct or indirect benefits derived from these functions, such as food production, climate regulation, water purification, and provision of raw materials.
To better understand the linkages between these functions and services, researchers are highlighting approaches such as using bromeliads as models in tropical ecosystems, the role of soil and its microbiome, and community participation in coastal zones. Integrating scientific and traditional knowledge is emerging as a critical tool for guiding sustainable conservation policies.
Bromeliads as ecosystem models
Monitoring environmental change in ecosystems requires strategies that integrate functional diversity and take into account local specificities, especially in tropical environments, explained Daiane Srivastava, University of British Columbia. She illustrated the problem using a model system based on bromeliads.
Bromeliads are plants whose leaves allow them to store water and form “pools” inside. This turns each plant into a mini-ecosystem that harbors animals, algae, bacteria and fungi. The organic matter that falls into the pond is recycled and can be used by the plant itself and by other organisms, making them a good model for studying how ecosystems function under different conditions.
The study presented by Srivastava examined 1,046 bromeliads at 26 sites across the Americas and found that these ecosystems respond differently depending on their location. For example, invertebrate diversity was more sensitive to changes in precipitation than total biomass. In other words, the biomass remains stable even though the species composition changes. These variations are related to the way bromeliads store water and the species composition at each site, and highlight the difficulty of establishing general limits for safe ecosystem functioning.
Although geographical contingencies influence these responses, they can be predicted by rules based on factors such as how they store water, the number of species that play similar roles in the ecosystem, and geographical features. This suggests that even in complex ecosystems, such as tropical ones, it is possible to generalize environmental response patterns if we know these rules.
However, Srivastava poses some challenges for ecosystem monitoring, such as “Which metrics of functional, taxonomic, interactional, or phylogenetic diversity are best for predicting ecosystem services? How can we ensure that we are measuring the right traits for conservation? And is functional diversity a more effective alternative to taxonomic diversity in the tropics? These questions highlight the importance of linking spatial and functional scales to guide conservation policy and management strategies.
Invisible Ecosystem Services
Soils play an essential role in providing ecosystem services, supporting approximately 95% of global food production. Despite their importance, it is estimated that only 1% of soil microorganism species are known. Soil biodiversity is critical not only for food production, but also for processes such as nutrient cycling, biological control and bioremediation.
According to George Brown of Embrapa Florestas, the ecosystem services associated with soil are valued at more than 1 trillion euros per year, with the recycling of organic matter accounting for 50% of this value. Despite this, Brown points out that the 2019 Global Diagnosis of Biodiversity and Ecosystem Services by the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) did not address this important contribution. In addition, a recent global survey by the Food and Agriculture Organization of the United Nations (FAO) found that few countries have specific inventories or monitoring programs for soil biodiversity. One exception is the sOilFauna project, a global initiative that maintains a database of soil fauna.
From microscopic animals such as microfauna (nematodes, tardigrades) and mesofauna (mites, springtails) to large invertebrates of macrofauna (ants, termites, earthworms, beetles, lacewings, spiders, various larvae) and vertebrates of megafauna (armadillos, moles), soil animals comprise more than half a million species worldwide. Many of them are promising bioindicators that respond rapidly to environmental changes and can be used to assess fertility, contamination levels, the effects of management practices, and the impact of environmental disturbances. In addition to being easy to collect and identify, they have high densities and biomass, especially in tropical regions where social insects dominate. Standardized methods are already available to facilitate the use of these bioindicators in different land-use systems. Recognition of their functionality can drive global action to protect soil biodiversity and maximize its ecosystem services, which are fundamental to a sustainable future for the planet.
Soil microorganisms are already known to play a role in improving the health and nutrition of crops. The most emblematic case is that of nitrogen-fixing bacteria. The microbiome is the totality of microorganisms, their genomes and functions in a given environment, including bacteria, fungi, archaea, protozoa and viruses. The diversity of these organisms is impressive: each gram of soil can contain up to 10⁹ microbial cells. This invisible ecosystem plays a critical role in nutrient cycling, disease suppression, soil structure and water purification. “In agricultural systems, practices such as no-till farming, green manuring, crop rotation, composting and crop-livestock-forest integration can increase microbial diversity, contributing to sustainability, greenhouse gas mitigation and ecosystem resilience,” explains Lucas Medes of the Center for Nuclear Energy in Agriculture at the University of São Paulo (CENA/USP).
On the other hand, changes in land use have a profound effect on the microbiome, says Mendes. A study comparing forest and pasture soils showed that forest soils have higher nitrogen and methane metabolism, while pasture soils release more methane and nitrous oxide.
Microbiome-based solutions have also shown promise in ecological restoration and agriculture. In experiments, increased microbial diversity was associated with better soybean growth and reduced nematode infection, highlighting the potential of microbial management to promote more productive and sustainable systems.
Community Involvement
Alexander Turra, from the USP Oceanographic Institute, highlights the complexity of coastal ecosystems and the need for holistic approaches to their conservation. He points to the challenges of studying coastal marine biodiversity, which requires diverse research methods, including the use of traditional knowledge. According to Turra, understanding the different environments of coastal zones, as well as ecological processes and responses to human pressures, is essential for formulating effective policies and action plans. In this context, the integration of science and society through participatory processes is fundamental to improving the understanding of ecosystem services and addressing threats to these environments.
One example is the 2016 Local Development Plan for Araçá Bay, in Ubatuba (SP), based on discussions about the impacts of a possible expansion of the port of São Sebastião. The document was the result of a collective effort involving local communities, research institutions, the private sector and public institutions. This plan demonstrates how community participation can be a catalyst for sustainable solutions adapted to local realities. He also mentions the Brazilian Marine and Coastal Diagnosis of the Brazilian Platform for Biodiversity and Ecosystem Services, which includes a chapter written by the community, demonstrating the power of collaborative approaches.
Among the challenges identified is the need to reveal, in a participatory way, the non-linear spatial patterns of marine biodiversity and ecosystem services on beaches. To this end, Turra suggests the use of scenarios and action plans that take into account multiple uses, address threats and promote sustainable development.
About the São Paulo School of Advanced Science “Co-designing Biodiversity Assessments”
Organized by Unicamp’s Graduate Program in Ecology, with support from Fapesp, the São Paulo School of Advanced Science “Co-creating Biodiversity Assessments” brought together 57 participants from 22 countries on four continents, including graduate students, early career researchers, environmental managers and technicians. The participants spent 14 days in São Pedro (SP) discussing ways to integrate academic and practical knowledge on biodiversity to support decision-making.