How land use affects climate change

The Hindu

 

Context

The interaction between people and land is as old as human evolution

 

Definitions

Anthropocene

Period relating to or denoting the current geological age, viewed as the period during which human activity has been the dominant influence on climate and the environment.

Holocene

The Holocene is the name given to the last 11,700 years* of the Earth’s history — the time since the end of the last major glacial epoch, or “ice age.” Since then, there have been small-scale climate shifts — notably the “Little Ice Age” between about 1200 and 1700 A.D. — but in general, the Holocene has been a relatively warm period in between ice ages

 

Peri-urban areas: Those areas which are outside city limits but not quite part of the rural hinterland (remote or less developed parts of a country)

 

What is the urban heat island effect?

An urban heat island (UHI) is an urban area or metropolitan area that is significantly warmer than its surrounding rural areas due to human activities. Consequently, under the UHI effect the cities remain warmer than the surrounding rural areas due to a lack of vegetation or evaporation

 

Points from the article:-

 

Evolution of interaction between people and land

  • Settling down of hunter-gatherers: When early hunter-gatherers started to settle down in the Neolithic transition and practice agriculture, they began to change their relationship with land in a major way
  • Domestication of plants:Starting with the Holocene, approximately 11,500 years ago, many plants were domesticated for agriculture
  • Formation of early cities:These and the associated social and technological changes led to dense human settlements that then paved the way for the formation of early cities

 

How does land-use change takes place through human activity?

Author states that land-use change takes place through human activity in several ways

  • Clearance of forest areas: Forest areas are often cleared for commercial or residential purposes For example, in Indonesia, about 500 sq km of forest area are cleared each year, much of which is replaced with oil palm plantations
  • Urbanization: The expansion of cities well beyond their limits transforms land use from agriculture and forests into industry, residential and commercial buildings and associated infrastructure, and horticulture
  • Transformation of Per-urban areas: As urbanization increases, Peri-urban areas are transformed into supply units that fulfill the necessities of the cities. Responsibilities ranging from growing of vegetables to pumping of groundwater for industries and acting as a dumping station for waste are borne by such areas

 

Multiple patterns of growth in India

Author states that in India varying patterns of urban and per-urban growth can be seen resulting in different consequences for each region. Examples

  • Mumbai: An excellent network of BEST (Brihanmumbai Electric Supply and Transport Undertaking) and suburban trains defined Mumbai early on in its growth
  • Bengaluru and Hyderabad: Unlike Mumbai, expansion and infrastructure development in these two cities took place primarily outside the core areas with the view to establishing and supporting public sector companies such as HMT, Bharat Electronics Limited, and the Defence Research and Development Organisation, and later Information Technology companies
  • Gurugram:Gurugram, south of Delhi, has become a centre for several kinds of industries and has developed into a financial and industrial hub

 

Implications

Author states that a city, based on its pattern of growth and expansion, can lead to particular lifestyles and restrict a quality of life for its many residents.

  • Impact on climate:
    • Activities impacting climate: Interventions like converting agricultural land for housing or industry, filling up ponds and building housing complexes on lake beds, etc. impact ecosystem services and climate adaptation. These especially affect the poor who are largely reliant on ecosystems for their livelihoods
    • Change in weather pattern: According to some scientists, land cover and land management practices influence local and regional weather patterns. This is largely due to changes in aerosols, carbon, nitrogen and other gases along with the moisture in the air, heat and light

Both urban and per-urban areas are affected: The urban heat island effect is understood readily, but this also affects peri-urban regions of expansion