This document discusses synergism in terrestrial ecosystems. Synergism refers to the combined effects of multiple factors being greater than the sum of their individual effects. The document provides examples of positive synergism between trees sharing roots, as well as negative synergism from toxic pollutant combinations harming species. Climate change, land use changes, pollution from pesticides and heavy metals can act synergistically to threaten biodiversity by disrupting species and food webs. Managing these stressors is important for protecting terrestrial ecosystems.

1. SYNERGISM IN TERRESTRIAL
ECOSYSTEM
Presented By: Hajrah Malik
1213-FBAS/BSES/S18

2. Synergism
Synergism is the joint action
of agents, as drugs, that
when taken together
increase each other's
effectiveness.
Alone we can do little, togather we can do
so much

3. Synergism in Ecosystem
◦ Ecology describes the synergism in
nature, every thing is related to
everything else
◦ Example: The great Sequoia trees grow
together in clumps. Their roots are
intertwinedand without each other they
would blown over in a storm

4. Negative Ecological Synergy
◦ Synergy can also be negative.
◦ When the effect of two components in ecology is worse than that expected from the
simplesum of these separate elements, is negativeEcological synergy.
Synergy in Toxicology
◦ Synergism is a term used by toxicologists to describe the phenomenonin which a
combination of chemicals has a toxic effect greater than the sum of its parts

5. Synergistic Effect in Forests
◦ Interactions between driving factors
◦ land use,
◦ climate,
◦ nitrogen deposition,
◦ biotic exchange
◦ atmospheric CO2
are synergistic.
When these co-
occur, their
combinedimpact on
plant growth is often
greater than
expected
potentially
causing
disastrous
dysfunction of
physiological
processes of
forests

6. Synergistic Effects on Terrestrial Species
◦ Many terrestrial species are highly vulnerable to
chemical pollution.
◦ The range of chemicals these species are regularly
exposed to is becoming increasinglycomplex.
◦ Due to the synergistic effect of these chemicals,
many terrestrial species are facing challenges which
then disturbs the whole terrestrial food web.
Importance of Terrestrial
Species:
They are key contributors
terrestrial food webs to
carbon cycling, soil fertility
and pest control.

7. Pesticides and
Heavy Metals
◦ Pesticides and heavy metals are two
types of pollutants that are commonly
present in the terrestrial environment.
◦ heavy metals are released into the
environment due to anthropogenic
activities and pesticides are commonly
used in agricultural fields to protect
crops and improvethe quality
◦ The synergistic toxicity of pesticides and
heavy metals causes the accumulation
in the digestive tract of earthworms,
which causes their death.

8. Acidification
and Heavy
Metal
Contaminati
on
◦ Acidification and heavy metal
contamination often work
synergistically because the acidic
waterhas low pH.
◦ Low pH levels encourages the
solubility of heavy metals so they are
released into the waterinstead of
being absorbed into the sediment
◦ As a result, heavy metals leach more
quickly from contaminated soils in
contact with acidic water.

9. Land use, Land Cover and
Climate Change
◦ According to research, climate and
land –use changes impact biodiversity
and species synergistically
◦ Habitat loss is greatest in areas with
fragmented landscapes and higher
mean temperatures
◦ Because biodiversity in fragmented
landscapes is more vulnerableto
climate change impacts than those in
relatively undisturbedcontinuous
landscapes
Climate and land‐use
changes are expected
to be the primary drivers
of future global
biodiversity loss.

10. References
◦ Chena, C., & Wangb, Q. (2015). The synergistictoxicity of the multiple chemical
mixtures:Implications for risk assessment in the terrestrial environment. Environment
International,77, 95–105. https://doi.org/10.1016/j.envint.2015.01.014
◦ McComb, B. C., & Cushman, S. A. (2020). Editorial: Synergistic Effects of Pervasive
Stressors on Ecosystems and Biodiversity. Frontiers in Ecology and Evolution, 8. Published.
https://doi.org/10.3389/fevo.2020.569997
◦ Oliver, I., Dorrough, J., Doherty, H., & Andrew, N. R. (2016). Additive and synergistic
effects of land cover, land use and climate on insect biodiversity. Landscape
Ecology, 31(10), 2415–2431. https://doi.org/10.1007/s10980-016-0411-9