Accuracy Assessment
In each land use/cover a minimum of five sample points were taken for accuracy assessment and ground truthing. Being the area very small the accuracy assessment of land use/cover showed overall classification accuracy of 73.25 % with Overall Kappa Statistics = 0.68 (Table 4). For user accuracy of 200 reference points and 200 classified points, 175 correct points were checked in the field. Higher user accuracy was found in wasteland (96.67%), followed by settlement (91.67%), agriculture (86.79%), and grasslands (86.67%), medium accuracy found in wetlands (66.67%), forest (86.49%) and low accuracy found in forest (28.00%) and waterbody (25.00%). On the contrary high user accuracy was observed in grasslands (92.86%) and agriculture (86.79%), medium accuracy was accessed in wetland (76.92%), settlement (73.33%), and wastelands (70.73), while low accuracy found in forest (63.64%), followed by waterbody (40.00%). The present study demonstrates the capability of geospatial technology to capture the land use/cover categories in a semi-arid region of upper Gangetic plains of Uttar Pradesh, India, which is important from the point of view of sustainable utilization of natural land resources, biodiversity conservation and management planning.
Land use/Land Cover Changes
The land use/cover-wise change detection analysis brought out very interesting trends in change in land use pattern from 2004 to 2010. During the six year period the land use/cover classes were altered remarkably in Chithara Village. During 2004, the maximum area was covered by agriculture 458.37 ha (52.60%) and wetlands 238.59 ha (27.38%) followed by settlements 109.23 ha (12.53%); the area covered by grassland (3.59%), waterbody (2.00%), wasteland (1.09%) and Forest (0.81%) was very minimal (Table 5; Figs. 5, 6). However, within a span of six years in 2010 the land use pattern showed drastic changes. The maximum area changed to Settlement became the dominant class (26.74%) and agriculture became second (23.18%). This was followed by wetlands (20.14%), grasslands (16.21%), wastelands (10.38%), forest (3.01%) and waterbody (0.34%). This showed significant incremental change in settlement by wastelands and grasslands and reduction in agriculture, wetlands by and water body. These significant changes in different land use/cover classes were the result of vigorous anthropogenic activities, rapid urbanization and population increase in the study area.
During 2004, the maximum area was covered by agriculture 458.37 ha (52.60%) followed by wetlands 238.59 ha (27.38%) and settlements 109.23 ha (12.53%). The overall accuracy assessment was found 73.25 % with 0.68 Khat.
Due to urbanization, area under settlements increased by adding 123.83 ha at the expanse of agriculture (-256.35 ha), wetland (-63.08 ha), and waterbody (-14.48 ha). The areas rich in wild biodiversity such as wetlands (-63.08 ha), and waterbody (-14.48 ha) were greatly affected due to expanding settlements and agriculture showing a decline in the land area under these categories over the six year period. However, during the same period area under the grasslands and wastelands which are also rich in biodiversity showed an increase.
The loss of wetland habitat will definitely affect the migratory birds in western Uttar Pradesh. Dadri wetlands, near Bil Akbarpur in Dadri harbor more than 220 migratory birds. A rare and endangered species bristled grass bird (Chaetornis striata) was recorded in 2010 with breeding nest in Dadri wetlands. Possibly it was the first record in India in recent times (Anon., 2010). As wetlands are destroyed some birds may move to other less suitable habitats putting survival as well as future migration in danger. Thus, many wetland birds are edging very close to extinction through disturbance and conversion of their habitats (Kumar et al., 2005).
The largest change occurred in wastelands to settlements (12.29%) and wastelands to agriculture (11.83%).Though, loss of agriculture due to settlement was 8.27% but the loss got compensated by conversion of wetlands to agriculture (5.40%). Loss of wastelands will result in loss of rich wild plant diversity as a number of ethno-botanical studies on wild/weed flora of waste lands of adjacent Bulandshahr district reported a number of valuable medicinal plants which are being used in traditional medicines by local people (Mashkoor Alam and Anis, 1987; Singh and Ahmad, 2010; Aggarwal et al., 2012; Chaudhary and Narayan, 2013). Disappearance of herbal flora in wastelands will deprive people of these medicinal herbs occurring in the wild and practicing the traditional way to cure various ailments by local population. Similarly, the grasslands, which also provide ecologically unique ecosystem were adversely affected and an area of 131.08 ha got converted to settlement and agriculture. Grasslands, mostly occupied by grasses such as Saccharum spontaneum L., S. bengalense Retz., and Phragmites karka (Retz.) Trin. ex Steud., are common in Gangetic plains along with scanty populations of other weeds predominantly those of Parthenium hysterophorus L., Cannabis sativa L., Chenopodium album L., etc. Grasslands provide traditional livelihood to local people as they utilize these grasses for various household purposes as well as products for sale.
There was change of 37.11 percent in the population compared to population as per 2001. In the previous census of India 2001, Gautam Buddha Nagar District recorded increase of 43.36 percent to its population compared to 1991.