Threats to soil biodiversity Flashcards
What can species loss result in?
Reduction in ecosystem productivity
What did a 1999 study conclude about species richness in soil?
Increased species richness in soil results in increased above ground biomass
Why is there a lack of data on species loss in soil?
Most studies focus on above ground organisms
How are soils characterised?
By their physical and chemical properties
Out of 909 soil families in China have been impacted by cultivation and construction?
359
A large proportion of European soils are under high levels of threat, in what areas is this worst?
Highly urbanised and populated areas
Give two examples of threats with high risk potential
Intensive human exploitation and organic matter decline
Give three examples of threats with moderate risk potential
Soil sealing, industrial pollution, and land use change
Give two examples of threats with low risk potential
Habitat fragmentation and use of GMO
Give an example of evidence that soil biodiversity is sensitive to human disturbances
Soil biodiversity decreases in tropical forests when converted for agriculture
In what ways does soil biodiversity change when land is repurposed for intensive agriculture, as found by a 2015 study?
Less diverse and trophically complex
What are the three hypotheses of the biodiversity-function theory?
Redundancy, linear, idiosyncratic
Describe the redundancy hypothesis in the biodiversity-function theory
High level of functional redundancy within communities (niche overlap). If one species is extinct, another will take its role. Tropic groups are maintained and the food web is intact.
Describe the linear hypothesis in the biodiversity-function theory
All species have a role and a loss of a species would cause a linear decline in function. There is a threshold where the system would collapse.
Describe the idiosyncratic hypothesis in the biodiversity-function theory
High level of functional redundancy but some are more redundant than others. Depends on some species having a more important role than others.
What did Jones et al (1994) conclude that the two types of organisms in ecosystem processes were?
Keystone species (alter system by tropic relations) and engineer species (alter system by physical disturbances)
Describe the insurance hypothesis, as described by Jones et al (1994)
Diverse communities are more likely to contain species that can withstand a changing environment, buffering the system against the loss of the species that cannot
What was the 1991 study in boreal forests about?
Decomposition rate of an organic substrate as a result of species biodiversity of a soil fungi
Which hypothesis did the 1991 boreal forest study support?
Supported the redundancy hypothesis
What did a 2014 and a 2021 study conclude about soil biodiversity and ecosystem multifunctionality?
Greater bacterial and fungal richness supported higher stability of the aboveground ecosystems (productivity and diversity) and the stability of litter decomposition and carbon assimilation
Why was a 2016 study into microbial biodiversity and multifunctional stability more applicable that the 2014 and 2021 studies?
Was carried out in the field
