A study by the MNCN-CSIC, in collaboration with the URJC, has shed light on how the different ecosystems that alternate dry and wet phases. To do this, soil organisms create biofilms during the wet phase and biological crusts in the dry phase.
When we study the natural environment, we tend to do that separation between terrestrial and aquatic ecosystemsbut what about those environments in which wet and dry phases alternate? A research team led by the National Museum of Natural Sciences (MNCN-CSIC) and Rey Juan Carlos University (URJC) proposes a new conceptual framework in the journal Ecology Letters that identifies the presence of water as the global engine that shapes life in these systems.
By considering the wet and dry phases as two inseparable components of the system, the interdisciplinary group, which brings together terrestrial and aquatic ecologists and microbiologists for the first time, has discovered that this alternation gives rise to a predictable sequence of organisms covering the substrate and which are able to maintain functions in both phases of this type ecosystems.
Maintaining ecosystem functionality
This work lays the foundation for a better understanding of how changes in global water availability might occur committed to biodiversity and human life on a planet with increasingly extreme climatic conditions. Moreover, it opens up new lines of research to meet the challenges of a constantly changing world.
“Contrary to what had been done, our conceptual framework integrates the wet and dry phases of transition ecosystems such as rivers and temporary lagoons, intertidal areas or floodplains,” explains MNCN researcher Rebeca Arias-Real.
Until this work, in ecosystems as the temporary lagoons in Doñana, for example, were unknown what happens in the ecosystem when it drieswhile in the boulevards or floodplains the wet phase is generally ignored.
“This biased view has led to a poor understanding of these ecosystemswhich limits our ability to preserve their biodiversity and the benefits they bring us, such as drinking water or the recycling of carbon and nutrients,” Arias-Real continues.
During the dry phase, organisms such as bacteria, fungi, algae, protozoa, archaea, bryophytes and lichens can give rise to so-called biological scabs. On the other hand, in the presence of water, these organisms take the form of biofilms, covering stones and fine substrate.
“Walking along a boulevard or even through grasslands, if we pay close attention we can see that the ground is usually covered with mosses, lichens and other small organisms that meet nature’s demands. essential functions for soil fertility and nutrient recyclingsays the MNCN researcher.
“On the contrary, if we step into a river and touch the stones and substrate, we will notice a gelatinous film, which is known as biofilm. Biological crust and biofilm are two sides of the same coin”, indication.
“While others Ecosystems experience irreversible changes after a disturbancethe transitions from aquatic to terrestrial are an essential part of these types of dynamic habitats. These reversible transitions between wet and dry states occur naturally and periodically over time intervals ranging from minutes to years, as they respond to water availability,” said Pilar Hurtado, researcher at the URJC.
“Consider the two phases of these ecosystems as one whole can help us better understand how climate change and other human influences could alter biodiversity patterns on a global scale and assess the level of threat to essential functions such as climate stability or food production.
In this sense it is vital to understand if there are biological scabswith a high ability to withstand drought, it can maintain functions during dry periods when changes in precipitation and temperature are becoming increasingly prolonged,” says Hurtado.
This study has shown that the resources the ecosystem uses to adapt to change and survive are enormous. The logical conclusion is: as long as we achieve it Don’t break the balance of the ecosystem, nature is certainly looking for its own ‘patches’‘ to correct our mistakes and their disastrous consequences.