Growth of the city

• Biotic diversity change and climate change is the major problem caused by rapid and unplanned development of urbanization. High population growth and more demand for land have been changing the urban landscape of Guwahati city.
• Urbanization in Guwahati is complex, diverse and fragmented which results in the modification of the natural land cover of the city. Guwahati the capital city and the gate way of north east India are also not exceptional on it. Guwahati is the capital city of Assam, which is among the states with low level of urbanization.
• 14.1 per cent of the state’s population was living in urban areas in 2011, which is an increase from 12.9 per cent in 2001 and 11.1 per cent in 1991 (Gogoi Lakhimi).After the shifting of the state capital from Shillong to Dispur , the city has been faced lots of problems which impact on the degradation of environment and poses as a threat to the biodiversity.
• To regulate the development, land use zoning has assigned the proposed Master Plan for Guwahati 2025. Urban landscape change has clearly seen over the eco-sensitive and Green belt areas, especially towards the periphery of the city (Borthakur Monjit, Nath Bhrigu Kr.).
• Transfer of capital from shilling to Guwahati and establishment of new industry and rampant growth of commercial activities has attracted large no of migrants from different parts of Assam and from the other parts of India. Migrants demanded for land and demand of land has increased in Guwahati rapidly. Encroachment over vulnerable lands, growth of several new colonies, filling up of low lying areas for residential establishments has expanded the city horizontally.
• The core areas of the city due to lack of land availability has expanded vertically causing dense urban structure (Gogoi Lakhimi). The city is growing rapidly in last few decades with growth rates of 131.60 in 1971-1991 and 38.59 in 1991-2001.The total area of the city was only 43.82 square kilometer in 1971. In 1974 it came under the administration of Municipal Corporation with 34 wards and the area increased to 216.79 square kilometers (Govt of Assam as mentioned by (Gogoi Lakhimi).Sectoral form of development can be seen in Guwahati incorporating new village areas day by day.

Land use change and natural resources depletion in Guwahati

• With the expansion of the city, the land use pattern has been changing resulting decrease of the natural resources. Due to the human anthropogenic activities land use pattern of the city has changed which can be seen from the following table:

• There has been considerable decrease in agricultural land (from 7% to5%), barren land (from 14% to 5%), and dense forest (from 19% to 11%). and swamps (11% to 8%) during the period 1977 – 2007. As expected, from 22.61 per cent of the total built up land area has increased to 43.59 per cent with a rate of increase of 3.09 per cent per year. (Gogoi Lakhimi).
• In a research paper Monjit Borthakur, Bhrigu Kr. Nath has calculated the Major Land Use and Land Cover Change in the Guwahati Metropolitan Area (1991 to 2009).The study has revels that low dense Settlement area decreased by 5.83 percent in 2000, as most of the low density areas were converted to high dense Settlement areas.
• National highway 37 from Jalukbari to Khanapara in 2000 and LGBN International Airport at Borjhar has also caused major change to land cover.

Impact on Deepor Beel Environment

• Rapid growth of city population and land cost increase has resulted in the encroachment of the Deepor Beel. Northern and eastern parts of the Beel have been occupied by the private as well as the government organizations. Encroachment has blocked the natural drainage pattern of the Deepor Beel causing the water level imbalance in the Beel.
• Soil erosion and improper catchment treatment and agricultural practices have led to sedimentation in the Beel. Encroachment problem and land use change has changed the special pattern of Deepor Beel water area. In a study by shows that the change in permanent water land has decreased by day by day.
• The permanent lake water area has decrease from 7.1 sq km in 1991 to 5.2 sq km in 2001 and to 4.2 sq km in 2010.Decrease in water body spatial extent of Deepor Beel Ramsar site is indication of adverse impact of urbanization.
• Growth of aquatic weeds has seen in the Deepor Beel area.Guwahati oil refinery waste is directed through the Bharalu and Kalmoni rivers to the Beel. The channels also carry other industrial and hospital waste to the Beel.
• The water has turned black and smelly. Sewage discharge into the water might have caused the fall in oxygen levels resulting in the death of fishes. Dumping of municipal solid wastes in its close proximity at Boragaon by the Guwahati Municipal Corporation (GMC) has pushed the wetland’s pollution to alarming levels.
• The problem has got aggravated during the monsoons, with rainwater sweeping large amounts of garbage from the dumping site to the Beel. Which now results the death of carp fishes – Rohu, Mrigal, Catla, etc, at the Deepor Beel was the maximum as compared to other species.
• Establishment of industries within periphery of the wetland system is leading to water quality deterioration and soil pollution. Permitting temporary brick kilns and associated soil quarrying from within the wetland have led to massive destruction of top soil and other ecosystem components.
• There are long term negative environmental impacts of establishment of brick kilns on soil productivity and soil micro-flora and fauna. Hunting, trapping and killing of wild birds and mammals and community fishing activities has adversely affected the Beel ecosystem.
• Community fishing and catching of gravid and brood fishes are causing sharp decline of fish productivity of the wetland. Species diversity and species habitat has been changed due to the unplanned fishing practice performed by the village people near the fringe areas of the Deepor Beel.