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Chapter Three Impacts of Global Climate Change

ecological relationships it helped establish within the ecosystem collapse, resulting in irre-
versible damage to biodiversity.
The decline in ecosystem service functions is another critical manifestation of irrevers-
ibility. Ecosystems provide humanity with numerous vital services, such as climate regula-
tion, water conservation, food production, and raw material supply. Forest ecosystems play a
pivotal role in regulating climate by absorbing carbon dioxide and releasing oxygen through
photosynthesis, maintaining the carbon-oxygen balance in the atmosphere. However, pro-
longed climate change has led to increased frequency of forest fires, intensified pest out-
breaks, reduced forest coverage, and degraded ecological functions. When forest ecosystems
suffer severe damage, their climate-regulating capacity significantly diminishes – a decline
that is often irreversible. Similarly, wetland ecosystems are crucial for water conservation
and purification. Yet due to climate change-induced reduced precipitation, declining water
levels, and unsustainable human exploitation, wetland areas continue to shrink. Their water
retention and purification capacities have consequently weakened, with little possibility of
restoration to original levels.
These irreversible consequences pose a significant threat to biodiversity and ecosystem
stability. Biodiversity serves as the foundation for ecosystem stability, and species extinction
reduces biodiversity, leading to simplified species composition in ecosystems and stream-
lined food chain and food web structures. This means ecosystems lack sufficient buffering
and regulatory capacities when facing external disturbances, resulting in a substantial decline
in stability. For instance, in an ecosystem, if a keystone species becomes extinct due to cli-
mate change, other species connected through predation, competition, or symbiotic relation-
ships will also be affected. This may trigger fluctuations in populations of multiple species or
even lead to extinctions, plunging the entire ecosystem into instability. The decline in ecosys-
tem service functions directly impacts human survival and development. For example, weak-
ened climate regulation may increase the frequency of extreme weather events, threatening
human life and property safety; reduced water retention capacity may cause water shortages,
affecting agricultural production and residents’ livelihoods. Therefore, gaining deeper under-
standing of the long-term cumulative effects and irreversibility of climate change in ecosys-
tems, implementing effective measures to protect ecosystems, and preserving biodiversity
and ecosystem stability have become urgent tasks in addressing climate change.

IV. Responses of Socioeconomic Systems to the Long-Term Cumulative
Effects of Climate Change
Within the long-term process of climate change, its cumulative effects continuously
permeate and reshapereshapingvarious levels of socioeconomic systems. To address these
impacts, socioeconomic systems have generated a series of adaptive responses in economic
development models and social structures. These responses not only concern current stable
operation but also influence the future trajectory of sustainable development.

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