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Created page with "```mediawiki == Biological Stress Factors, Environmental Risks == The first version of this article was produced in 2004/2005, when the interdisciplinary field known as “[h..."

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== Biological Stress Factors, Environmental Risks ==

The first version of this article was produced in 2004/2005, when the interdisciplinary field known as “[https://en.wikipedia.org/wiki/Earth_system_science Earth System Science]” was still emerging; it only appeared on Wikipedia in 2009.

At the international scale, establishing programs to define indicators, map, and monitor all systemic risks weighing on the planetary environment is increasingly likely to become a major priority.

It is interesting to observe that, over the years, these risks are gradually being taken into account—especially where long-term societal and economic stakes are monitored (World Forum, UN).

=== Direct measurements of biodiversity ===

Biodiversity responds to the pressure that the environment exerts on living organisms.<br>
Measuring biodiversity therefore provides an indirect way to measure biological stress.

Given current knowledge and measurement capabilities, it seems difficult to evaluate biodiversity at the scale of entire regions: this can only realistically be done locally.
A few methods exist for this:

* Abundance–Biomass Comparison (ABC) method: calculation of the disturbance level (Clarke & Warwick, 2001a)<ref name="clarke_warwick_2001a"/>
* Shannon diversity index or Shannon–Wiener (H') (Pohle et al., 2001)<ref name="pohle_2001"/>
* Species abundance curve
* Average Taxonomic Distinctness (AvTD) and Variation in Taxonomic Distinctness (VarTD) (after Clarke & Warwick, 2001b): their mean values are independent of sampling effort; the response to increasing environmental stress is monotonic (i.e., it decreases or increases with the level of disturbance)<ref name="clarke_warwick_2001b"/>

Biodiversity responds to the environment and to the pressure it exerts. Since, in the context of this study, we are specifically interested in what disrupts biodiversity, it is not necessarily useful to measure it directly; rather, we should focus on the pressures the environment applies.

This can be assessed by identifying sources of biological stress.

=== Biological stress ===

Biological stress is expressed through aggressions against the environment; it favors the development of certain species to the detriment of many others. A “stressed” ecosystem will respond with an overall impoverishment in absolute number of species, benefiting a few that will occupy the most impacted—or even vanished—ecological niches.

[[image:richesse-specifique.jpg|thumb|centre|800px|Ranked mean species abundance (or dominance) curves (a) and ranked cumulative abundance curves (k-dominance curves) (b), for samples from altered stations located near (dashed line) an oil drilling operation and from relatively less affected stations (solid line), representing populations experiencing different types of biological stress (after Clarke & Warwick, 2001a).]]

[[image:abondance-biomasse.jpg|thumb|centre|800px|Abundance–Biomass Comparison (ABC) method to calculate disturbance level, based on comparing biomass (species biomass) and abundance (k-dominance) curves, showing the relative positions of curves at different degrees of pollution (after Clarke & Warwick, 2001a).]]

<b>“abundance”:</b> % of individuals belonging to species i<br>
<b>“biomass”:</b> % of total biomass represented by species i<br>

=== Environmental Vulnerability Index (EVI) ===

Listing vulnerabilities is a task that should increasingly concern future generations—especially as they will be confronted more and more with global climate change.

For example, the [http://www.u-sphere.com/data/environmental_risks/Environmental%20Vulnerability%20Index.htm Environmental Vulnerability Index (EVI)] is a measure designed by the South Pacific Applied Geoscience Commission (SOPAC) and the United Nations Environment Programme (UNEP) to characterize the relative severity of various types of environmental problems. EVI results are used to focus on planned solutions to negative environmental pressures, while promoting sustainability.<ref name="evi_sopac_unep"/>

These vulnerabilities are structured according to a 3-level logic (see the next chapter):
* Environmental source system(s)
** Natural or artificial disruptive factors (stressors)
*** Measurable indicators

See [https://en.wikipedia.org/wiki/Environmental_Vulnerability_Index Environmental Vulnerability Index] on Wikipedia.

=== Examples of stress factors ===

* Climatic phenomena,
* Precipitation,
* Droughts,
* Heat load,
* Storms,
* Frost events,
* Pollution,
** Drilling,
** Acid rain,
** Mutagenic elements, [[rayonnements électromagnétiques|electromagnetic radiation]],
** Changes in dissolved oxygen concentration,
* Fires,
* Biological phenomena,
** Nutrient content in food,
* Geological phenomena,
** Volcanic eruptions,
** Avalanches,
** Landslides, ...

=== Examples of measured variables ===

In all cases, starting from these environmental factors, the goal is to identify measurable indicators and determine the most important factors. These must be measured over sufficiently long durations to be considered “relevant/critical”. For example:

* Changes in pH,
* Sulfate concentration (SO4/SO2),
* Phosphorus / phosphate concentration (P/PO4),
* Nitrogen concentration (N/NO3),
* Vertical and horizontal ozone concentration (O3),
* Photosynthetically active radiation,
* Air temperature at the ocean surface (satellite),
* Chlorophyll concentration measurements,
* Atmospheric dust concentrations,
* CO2 levels, ...

== Classification of environmental systems ==

We can classify environmental risks according to their environmental '''sphere''' of origin. On U-Sphere, this breakdown was used:

* The [[Héliosphère|Heliosphere]], the [[Magnétosphère|Magnetosphere]],
* The Atmosphere,
* The Lithosphere,
* The Hydrosphere, Cryosphere,
* The “Cosmosphere”,
* The Anthroposphere

<div style='background-color:#e3e3e3; border-radius:10px; padding:10px;'>
=== Cosmosphere ===

* [[rayons cosmiques|Cosmic radiation]]

In general, dust or volcanic explosions cause cooling of Earth’s atmosphere, because they reflect part of the Sun’s energy back into space and cool the planet. However, very energetic [[rayons cosmiques|cosmic rays]] interact only rarely; when they do, they break molecules in the upper atmosphere—typically CO2. This counteracts the greenhouse effect; furthermore, the broken molecules recombine to form water-vapor clouds that modify the planet’s albedo and can create imbalances.

* Meteors, Comets

The Solar System is crossed by objects of various sizes that can represent a major risk for Earth.
Until recently, these risks largely escaped any possibility of control; today, space agencies—and NASA in particular—are setting up [https://en.wikipedia.org/wiki/Sentry_(monitoring_system) monitoring programs].
</div>

<div style='background-color:#f9f6df; border-radius:10px; padding:10px;'>
===[[Héliosphère|Heliosphere]], [[Magnétosphère|Magnetosphere]]===
[[image:Heliosphere-var.jpg|thumb|right|200px|The Sun is the source of many phenomena that can impact the terrestrial environment]]
The variability of solar activity—and the limited historical depth of our observations—means this risk is still largely underestimated.

'''Surface of the [[Héliosphère#soleil|Sun]]'''
* [[Héliosphère#Nombre de Wolf|Wolf number]] (a very general parameter associated with increased solar activity)
** [[image:database.gif]] [http://sidc.oma.be/DATA/monthssn.dat Wolf number from January 1946 to January 2003]
** [[image:risk-indirect-correlation.gif]]+[[Stress biologique#Nb de Wolf|k(Wolf number, plant mortality)]]
* [[Héliosphère#Eruption solaire|Solar flares, Coronal Mass Ejection (CME)]]
'''Solar plasma'''
* [[Héliosphère#Vent solaire|Solar wind]]
** V Solar wind velocity,
* [[Héliosphère#Aurores boréales|Auroras]]
** [[image:risk.gif]][[Effets_des_Rayonnements_%C3%A9lectromagn%C3%A9tiques#cas2._Aurores_Bor.C3.A9ales|EM effects of auroras]]
** [[image:database.gif]] Number of auroras
** [[image:risk-indirect-correlation.gif]] k(auroras, plant mortality)
** Variation of Earth’s geomagnetic field
*** [[Héliosphère#Ap Index|Ap Index]], [[Héliosphère#Kp Index|Kp Index]],
**** [[image:database.gif]] ftp://ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP/
**** [[image:risk-indirect-correlation.gif]] [[Stress biologique#Ap Index|k(Ap Index, plant mortality)]]
**** [[image:risk-indirect-correlation.gif]] [[Stress biologique#Ap Index|k(?, human mortality)]]
** Dst Index,
** Bz Component
* Proton flux
** Tp proton temperature,
** Dp proton density.
'''[[Héliosphère#Rayonnement EM du soleil|Solar radiation / radiations]]'''
* ElectroMagnetic Fields (EMF)
** Effects of [[Rayonnements_électromagnétiques|electromagnetic radiation]] [[image:heliosphere-weather-lanzerotti.jpg|thumb|right|200px|Effect of electromagnetic radiation]]
** [[H%C3%A9liosph%C3%A8re#UV|UV]],
*** [[image:database.gif]] [ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_UV/UVCOMPOSITE/ MGII Ion emission]
** [[Héliosphère#EUV|EUV]],
** Density variation of the [[ionosphère|ionosphere]]
*** [[image:database.gif]] Measurement of F0F2
'''[[Héliosphère#Interplanetary Magnetic Field (IMF)|Interplanetary Magnetic Field]]'''
'''EM fields generated by solar plasma (/EUV?)'''
* [[Rayonnements_%C3%A9lectromagn%C3%A9tiques#Extr.C3.AAmement_Basses_Fr.C3.A9quences_.28ELF.29|ELF currents (Extremely Low Frequency) generated in the ionosphere]]
** [[image:risk.gif]][[Effets_des_Rayonnements_%C3%A9lectromagn%C3%A9tiques#Effets_des_Champs_Electriques_d.27Extr.C3.AAmement_Basse_Fr.C3.A9quence_.28ELF.29|EM effects of ELF]]
** [[image:database.gif]] ELF currents value
** [[image:risk-indirect-correlation.gif]] k(ELF currents value, plant mortality)
* <b>“Galactic weather” (interface solar wind / galactic medium)</b>
</div>

<div style='background-color:#edf6fd; border-radius:10px; padding:10px;'>
=== Atmosphere ===

Essentially an interface for storing aerosols and particles, and transforming them under the effects of temperature and solar radiation.

[[image:Atmosphere-coupling.jpg|thumb|right|200px|Beyond climatic phenomena, the atmosphere mediates a set of processes related to human activity.]]

* The [[Effet de serre|greenhouse effect]]
** Greenhouse gases: H2O, CO2, CH4, N2O, O3, halocarbons
** [[Héliosphère#infrarouge|Infrared]] radiation
** [[image:risk.gif]] Anthropogenic production of greenhouse gases
*** CO2 (55%), CH4 (15%), halocarbons (15%), O3 (15%), N2O (5%)
*** >> Increase in global temperatures
* [[Ozone#couche d'ozone|Stratospheric ozone layer]] (~25 km)
** Production of [[ozone]] by absorption of [[Héliosphère#UV|UV]] radiation
* Atmospheric pollutants
** [[image:risk.gif]] Aerosol production: destruction of the [[Ozone#couche d'ozone|stratospheric ozone layer]]
** [[image:risk.gif]] Production of [[ozone]] and pollutants in the lower atmosphere
*** >> “Storage”: [[Inversion de températures|temperature inversion]] phenomenon
**** [[image:risk.gif]][[Inversion de températures#Smog|smog]],
**** [[image:risk.gif]] Acid rain
* Tropical storms, cyclones
* Air temperature
</div>

<div style='background-color:#e7eeff; border-radius:10px; padding:10px;'>
=== Hydrosphere, cryosphere ===

* Droughts,
* Floods,
* Tsunamis,
* Ice-melt rate,
* Changes in rivers or bodies of water,
* Dissolved oxygen and CO2 levels, ...

</div>

<div style='background-color:#f4ffee; border-radius:10px; padding:10px;'>
=== Biosphere ===

Here we consider feedbacks linked to the activity of living species in relation to environmental changes and to shifting equilibria.

* [[http://fr.wikipedia.org/wiki/Eutrophisation Eutrophication]],
** Increase in algal biomass,
** Increase in gelatinous zooplankton biomass,
** Degradation of the organoleptic qualities of water (appearance, color, odor, taste),
** Development of toxic phytoplankton,
** Decrease in biotic index,
** Decrease in dissolved oxygen concentration,
** Death of higher organisms (macrophytes, insects, cnidarians, crustaceans, mollusks, fish, etc.).

* Changes in ocean currents.

(These causes are not strictly tied to the hydrosphere alone, but are linked to exogenous human and ecological factors.)

<u>Related markers/variables</u>

* Plankton biodiversity
It is essential for the biodiversity of species that feed on it, and also to cope with the spatial and temporal variability of environmental constraints. Thus, the quality of a marine ecosystem can be assessed through the quality of its “plankton spectrum” (zooplankton and phytoplankton).
* Coral growth
These are markers of past climate and of pollution levels.
</div>

<div style='background-color:#ffe0e0; border-radius:10px; padding:10px;'>
=== Anthroposphere ===

Here the goal is to measure systemic footprint through human activities.

* Decision and control zones (governments, command centers),

* Pollution and contamination zones:
** Nuclear,
** Bacteriological,
** Chemical and industrial,

* Resource exploitation zones:
** Natural resources (still) available,
** Exploitation of natural/biological resources,
** Contamination of ecological environments,
** Destruction of species and habitats,

* Conflict zones
</div>

<div style='background-color:#eae6e3; border-radius:10px; padding:10px;'>
=== Lithosphere ===

* Plate tectonics
** Volcanism,
*** Dust and gases >> atmosphere
** Earthquakes,
*** Tsunamis,
* Tilt, precession, ecliptic
</div>

== Coupling of risks and flows ==

[[Image:File-vsd.gif]] [http://www.u-sphere.com/data/environmental_risks/biosphere-risques.VSD biosphere-risques.vsd]

[[image:Biosphere-risques.gif|thumb|centre|200px|Biosphere — coupling of environmental risks]]

== Human attitude toward systemic risks ==

=== A strategic monitoring plan ===

The survival of the species and environmental equilibria depends upstream on monitoring the parameters listed above.

The environment acts on humans, and in return humans act on the environment: '''factors of social evolution''' must therefore be taken into account.

Likewise, '''the evolution of scientific and technical means (Technosphere)''' will shape interactions between humans and their environment, and their ability to modify the environment in which they live.

Here are additional parameters that should be considered:

=== Human development ===

* Industrial,
* Demographic,
* Social,
* Ideological,
* Scientific,
* Biological (at the species level).

=== Society’s reaction capacities ===

* Psychosocial tendencies toward submission,
* Psychosocial tendencies toward conserving attitudes,
* Subordination of technology.

We draw a parallel here between this kind of monitoring and the monitoring that other intelligent species in the universe might carry out, for the purpose of their survival and/or to understand the ecological systems they may encounter.

== References ==

<references>
<ref name="clarke_warwick_2001a">Clarke, K.R.; Warwick, R.M. (2001a). Reference cited for the Abundance–Biomass Comparison (ABC) method and ranked abundance/dominance curve interpretation.</ref>
<ref name="pohle_2001">Pohle et al. (2001). Reference cited for the Shannon/Shannon–Wiener diversity index (H').</ref>
<ref name="clarke_warwick_2001b">Clarke, K.R.; Warwick, R.M. (2001b). Reference cited for Average Taxonomic Distinctness (AvTD) and Variation in Taxonomic Distinctness (VarTD) and their properties.</ref>
<ref name="evi_sopac_unep">Environmental Vulnerability Index (EVI): developed by SOPAC with UNEP to characterize relative severity of environmental problems; used to guide planned solutions and promote sustainability.</ref>
</references>
```

Environmental Systems Risks - Revision history

Uadmin: Created page with "```mediawiki == Biological Stress Factors, Environmental Risks == The first version of this article was produced in 2004/2005, when the interdisciplinary field known as “[h..."