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Global Climate Change and Its Impacts

dependent, and the migration of any single species will affect other members. For example,
when herbivores migrate to new regions, the local vegetation structure changes, subsequently
impacting insects and other small animals that rely on these plants for sustenance. This chain
reaction can cascade through trophic levels, ultimately influencing the behavioral patterns
and survival status of apex predators.
(IV) Migration Barriers and Habitat Fragmentation
While some species can successfully migrate to more suitable environments, not all or-
ganisms are so fortunate. Urban expansion, agricultural development, and infrastructure con-
struction have caused habitat fragmentation, obstructing normal migration routes for many
species. Insufficient connectivity between wildlife reserves makes it difficult for certain spe-
cies to find adequate space to maintain population sizes. Species with limited long-distance
migration capabilities are particularly vulnerable to such geographical isolation, increasing
their risk of extinction.

II. Biodiversity Loss

(1) Accelerated Species Extinction Rates Due to Climate Change
Global climate change has significantly accelerated the rate of species extinction. With
rising temperatures, altered precipitation patterns, and increased frequency of extreme weath-
er events, many species struggle to adapt to rapidly changing environmental conditions, ulti-
mately facing extinction. According to data from the International Union for Conservation of
Nature (IUCN) Red List, approximately 28% of global plant and animal populations current-
ly exist in endangered or threatened status. Scientists estimate that if effective measures are
not taken to mitigate the impacts of climate change, up to 30% to 50% of species could face
extinction risks by 2100.
The primary threats posed by climate change to species survival include habitat loss,
food resource scarcity, disease transmission, and disruption of reproductive cycles. For in-
stance, the melting of polar ice caps has deprived Arctic animals like polar bears of crucial
hunting and breeding grounds; intensified aridification trends have exacerbated the degrada-
tion of grasslands and forests in the Horn of Africa region, forcing numerous wildlife species
to migrate in search of new habitats. Warm and humid climatic conditions facilitate the pro-
liferation of pathogens and parasites, increasing disease transmission risks. The expanding
distribution range of certain tropical diseases poses threats to both local wildlife and human
health. Temperature changes also affect the reproductive cycles of animals andplants, such as
earlier or delayed flowering times and altered migration routes. This temporal mismatch may
prevent normal interspecies mating or reproduction, thereby impacting population growth.
(II) Loss of Key Species Threatens Ecological Chain Stability
In ecosystems, certain species play crucial roles and are referred to as “keystone spe-
cies” or “cornerstone species.” Their presence or absence directly affects the structure and
function of the entire ecological chain. When these keystone species disappear, the entire

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