Tuesday’s Soil Ecosystem Service – Soil biodiversity
Description: In contrast to the atmosphere, hydrosphere and geosphere, the pedosphere (soils) is poorly known. Being composed of minerals and altering gaseous and aqueous substances (soil water and soil air) it is a very special habitat, hidden to human eyes. A pedosphere is a special place populated with a myriad of very diverse organisms that perform processes that are crucial to terrestrial ecosystems. It is known that a handful of soil contains more organisms than there are humans on Earth. Soil ecosystem biodiversity can be described as an abundance of genes, important for above ground ecosystem and humans.
Soil processes and soil properties affect soil biodiversity: The soil biodiversity is strongly determined by soil properties. Soil properties such as pore volume (a living place of soil organisms), the presence of water, air and nutrients, quantity and type of organic matter, etc. as well as inter and intra-species relationships define the diversity and abundance of populations of soil organisms. Soil biodiversity is a dynamic property. It is changing daily and seasonally as well as on a long-turn basis due to climatic change or soil degradation. It is difficult to record and compare the biodiversity of soils as it includes many different groups of organisms and only some of them are sufficiently known. Thus, evaluation of soil biodiversity is subject to many uncertainties.
Connection to the entire terrestrial ecosystem: Both, soil and aboveground biodiversity, are steered/defined by soil properties, human interventions (i.e. agricultural or urban land use) and climate (change). The dominant role of soils for aboveground biodiversity is still not adequately recognised. When talking about biodiversity, the agricultural or forest soil quality is not discussed, is not important. What matters is the diversity. In contrast to soils rich with nutrients and basic soils, nutrient-poor, shallow or acidic soils attract/host different plant, fungal and animal species.
Relation to other services: Soils, abundant with “life”, is highly valued as a gene pool. Soil biodiversity affects and is a driver of many regulating services. Soil organisms control pests, they are decomposing soil organic matter, store and cycle of nutrients, decompose pollutants, etc. In general, soil biota strongly contributes/enables the performance of other soil services such as biomass production, water filtration and purification, nutrient and carbon cycling and regulation.
Land use impacts: Below ground biodiversity as above ground is primarily a result of soil properties and land use. Soil properties determine the abundance and diversity of soil organisms in soil itself as well as the diversity and abundance of above-ground biodiversity. Soil and above-ground biodiversity are often drastically changed to meet human needs (i.e. unsustainable soil management), for example, the aboveground biodiversity is fundamentally minimised due to agriculture or compromised by invasive alien species. Soil changes (fertilizing or nutrient depletion, acidification, salinization, soil organic matter decline, etc.) and land use are reflected on soil biodiversity and above-ground biodiversity. Sustainable agricultural and forest practices inherit an increased below and above ground biodiversity.
Climate change impacts: In the course of climate change (i.e. higher temperatures and longer dry periods) soil properties are also changed what affects soil ecosystem conditions. By this, they affect /change soil and above-ground biodiversity. Populations of different soil species changes or adapt to altered soil conditions or they vanish.
Ecosystem function: For climate change impact mitigation high biodiversity is essential as it promotes the resilience of ecosystems. Hence, the societal awareness on the importance of this service should be high.