four decades of forest loss droughts in...

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FOUR DECADES OF FOREST LOSS DROUGHTS IN KERALA Energy and Wetland Research Group, Centre for Ecological Sciences, Indian Institute of Science, Bangalore; Web: Url: http://wgbis.ces.iisc.ernet.in/energy/ RAMKRISHNAN R., T. V. RAMACHANDRA Department of Civil Engineering / Energy and Wetland Research Group, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012 Email: [email protected], Phone: 080 22933099 Web: http://ces.iisc.ernet.in/energy, http://ces.iisc.ernet.in/biodiversity ACKNOWLEDGEMENTS The authors would like to thank Mr . Bharat Setturu, Mr . Nimish Gupta, and Mr . Vinay S ., for their priceless help and support. We also thank the Department of Civil Engineering, Indian Institute of Science, Bangalore and Amrita Vishwa Vidyapeetham, Coimbatore, for their support. We also extend our sincere gratitude to all other staff and Research Scholars in the Energy and Wetland Research Group at the Centre of Ecological Sciences, Indian Institute of Science, Bangalore. The state of Kerala has been gifted with vibrant climate and vivacious geological features to support different types of ecosystems. Blessed with such a great diversity in the State’s LAND USE DYNAMICS OF KERALA Kerala - Geography and Demography Latitude 8°18' to 12°48‘ N Longitude 74°52' and 77°22‘ E Language Malayalam Area 38,863 km 2 Elevation 2,695 m to −2.2 m Population 33,387,677 (2011) Annual Rainfall 2,923.4 mm physical settings, it is no surprise that the urban population of Kerala has registered a huge growth over the last few decades. This has given rise to several changes within the state, demographic as well as economic. What started with a gentle push from the government policies set in place in the 1940s received a further lunge due to a shift from food crops towards export-oriented crops in the 1960s. Kerala has been the subject of various changes in development patterns over the past few decades. Increasing urbanization rates require access to more free land for development, which has become detrimental to our existing forest cover. Google Earth Images showing temporal variation of Forest Cover 1984 1994 2004 2016 0 5,000 10,000 15,000 20,000 25,000 Forest Plantations Agriculture Water Urban Open Areas Area, km 2 Forest Plantations Agriculture Water Urban Open Areas 1973 24,953 1,851 4,305 350 95 6,143 2016 15,889 9,999 5,179 389 4,136 2,103 Temporal variation of Land Use in Kerala (Area covered shown below chart, in km 2 ) Evidence of deforestation, although not available on paper, is widely visible and rings a warning bell against the unsustainable use of land in the state. Another factor that put the cogs of deforestation in motion is interregional migration within the state, leading to an imbalance in ecology. Rapid urbanization with a high % of urban population of 47.72%, also encourages acquiring more agricultural or forest land near the urban centres, thus catapulting the process of deforestation even more. Methodology LAND COVER DYNAMICS Kovalam, Trivandrum Images showing rapid urbanization of two sites from 2003 to 2016 (Centre image shows emerging built up areas in red) Vypin, Kochi CONCLUSION: Change in land use patterns and urbanization leads to several undesirable conditions within the state. The state of Kerala receives orographic rainfall which depends on the Western Ghats. Loss of forest cover on the Ghats could affect the rainfall patterns in such a case. A reduction in forest cover even results in flash floods with no forest cover to arrest the intensity of runoff. Due to the run-off water facilitating erosion of top soil, silting happens in dam reservoirs which could count towards a noted average reduction of 22% in State’s dams’ water storage compared to last year September. This could indeed point us in the right direction as to why the state is witnessing one of its worst drought periods till date.

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Page 1: FOUR DECADES OF FOREST LOSS DROUGHTS IN KERALAwgbis.ces.iisc.ernet.in/biodiversity/sahyadri_enews/newsletter/Issue62/Posters1/Kerala...vibrant climate and vivacious geological features

FOUR DECADES OF FOREST LOSS DROUGHTS IN

KERALAEnergy and Wetland Research Group, Centre for Ecological Sciences,

Indian Institute of Science, Bangalore; Web: Url: http://wgbis.ces.iisc.ernet.in/energy/

RAMKRISHNAN R., T. V. RAMACHANDRADepartment of Civil Engineering / Energy and Wetland

Research Group, Centre for Ecological Sciences,

Indian Institute of Science, Bangalore 560012

Email: [email protected], Phone: 080 22933099

Web: http://ces.iisc.ernet.in/energy,

http://ces.iisc.ernet.in/biodiversity

ACKNOWLEDGEMENTSThe authors would like to thank Mr. Bharat Setturu, Mr. Nimish Gupta, and Mr.

Vinay S., for their priceless help and support. We also thank the Department of

Civil Engineering, Indian Institute of Science, Bangalore and Amrita Vishwa

Vidyapeetham, Coimbatore, for their support. We also extend our sincere

gratitude to all other staff and Research Scholars in the Energy and Wetland

Research Group at the Centre of Ecological Sciences, Indian Institute of Science,

Bangalore.

The state of Kerala

has been gifted with

vibrant climate and

vivacious geological

features to support

different types of

ecosystems. Blessed

with such a great

diversity in the State’s

LAND USE DYNAMICS OF KERALA

Kerala - Geography and Demography

Latitude 8°18' to 12°48‘ N

Longitude 74°52' and 77°22‘ E

Language Malayalam

Area 38,863 km2

Elevation 2,695 m to −2.2 m

Population 33,387,677 (2011)

Annual Rainfall 2,923.4 mm

physical settings, it is no surprise that the urban population of Kerala has registered a huge growth

over the last few decades. This has given rise to several changes within the state, demographic as

well as economic. What started with a gentle push from the government policies set in place in the

1940s received a further lunge due to a shift from food crops towards export-oriented crops in the

1960s. Kerala has been the subject of various changes in development patterns over the past few

decades. Increasing urbanization rates require access to more free land for development, which has

become detrimental to our existing forest cover.

Google Earth Images showing temporal variation of Forest Cover1984 1994 2004 2016

0 5,000 10,000 15,000 20,000 25,000

Forest

Plantations

Agriculture

Water

Urban

Open Areas

Area, km2

Forest Plantations Agriculture Water Urban Open Areas

1973 24,953 1,851 4,305 350 95 6,143

2016 15,889 9,999 5,179 389 4,136 2,103

Temporal variation of Land Use in Kerala (Area

covered shown below chart, in km2)

Evidence of deforestation, although not available on paper, is widely visible and rings a warning

bell against the unsustainable use of land in the state. Another factor that put the cogs of

deforestation in motion is interregional migration within the state, leading to an imbalance in

ecology. Rapid urbanization with a high % of urban population of 47.72%, also encourages

acquiring more agricultural or forest land near the urban centres, thus catapulting the process of

deforestation even more.

Methodology

LAND COVER DYNAMICS

Kovalam

, Triv

and

rum

Images showing rapid urbanization of two sites

from 2003 to 2016 (Centre image shows

emerging built up areas in red)

Vyp

in, K

och

i

CONCLUSION: Change in land use patterns and urbanization leads to several undesirable conditions within the state. The

state of Kerala receives orographic rainfall which depends on the Western Ghats. Loss of forest cover on the Ghats could

affect the rainfall patterns in such a case. A reduction in forest cover even results in flash floods with no forest cover to arrest

the intensity of runoff. Due to the run-off water facilitating erosion of top soil, silting happens in dam reservoirs which could

count towards a noted average reduction of 22% in State’s dams’ water storage compared to last year September. This could

indeed point us in the right direction as to why the state is witnessing one of its worst drought periods till date.