Department of Geography & Applied Geography
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Item Open Access A study on the impact of environmental degradation on river behaviour in jaldhakaduduya watershed, jalpaiguri district, West Bengal(University of North Bengal, 2023) Sarkar, Sriparna; Sarkar, SubirA watershed or a drainage basin consists of a main or trunk river, with several tributary river channels, both perennial and non-perennial, converging with the trunk river and spreading both water and sediments throughout the area covered by the entire network of channels. Movement of water and sediments, controlled by several geologic, physiographic, meteorological and anthropological factors may be affected by alterations in any of these factors, affecting thus, the entire fluvial dynamics of the watershed itself. This applies especially to watersheds located in areas, having a propensity to delicate ecological balance. Watersheds located between physical units with different structural and physiographic characteristics, or threshold regions are marked by more frail ecological balance, having long term effects on economy and livelihood of an entire region. The Jaldhaka- Duduya Watershed situated at the heart of the Eastern Himalayan Foothills known as Duars or Dooars, covering parts of Jalpaiguri and Alipurduar districts of West Bengal, India provides a typical example of such an area. Interaction of physical and anthropogenic factors leading to land degradation, riverbank erosion and soil erosion, causing hardships for the agro- based economy of the watershed. Qualitative and quantitative assessment of the problems through reconnaissance surveys, extensive field surveys were done to study the both the causes and effect of environmental degradation on river behavior within the selected study area.The Jaldhaka- Duduya watershed, is made up of two broad physiographic regions, which may be stated as micro- thresholds, located within a short longitudinal distance (<100km). These are the distal alluvial fan surface region of the northern plains in the north and the floodplain of Jaldhaka and Duduya in the south has marked differences in rainfall regime, soils and natural vegetation, clearly visible within relatively short distance from the mountain front, which marks the northern boundary. The piedmont terraces lying at the base of the mountain front marks the active alluvial fan surface. The Jaldhaka River, originating from the Lesser Himalayas of Sikkim, is the main river of Jaldhaka, while River Duduya originating from the piedmont terrace region lying at the base of Himalayan Foothills is the main river of the Duduya watershed. The northern part, constituted by quaternary deposits of various sizes forms the entire piedmont and the escarpments bordering them. The floodplain consists of mostly sandy soil, mixed with silt, with slight increase of clay at the extreme south. The Jaldhaka and its major tributaries flow through north-south trending faults and fault lineaments which were created due to neo-tectonic activities in Bhutanese Lesser Himalayan zone. The Rethi, which constitutes the Lesser Himalayan and the piedmont section of R. Duduya, also follows quaternary fault lineaments. Relief zones of the Jaldhaka- Duduya watershed show rapid change of elevation within small distances; a very small area in the extreme north in Sikkim with >4000m elevation from sea level, forming the source region of Jaldhaka. About 25% of the northern and north-eastern part of the watershed located in Bhutan’s territory, has 2500-1000m elevation from sea level, marking the source regions of the major tributaries of Jaldhaka, namely, Daina, Chamurchi and Rethi Rivers. More than 50% of the Jaldhaka- Duduya watershed has 50- 100m above sea level, forming the southern floodplain. The Jaldhaka- Duduya watershed experiences tropical warm and moist climate, receiving copious monsoon rainfall. High rainfall mostly occurs due to formation and stationing of the monsoon trough over the neighbouring Sikkim or Bhutan Himalayas, or from low pressure areas, which are created during the monsoon, bringing in heavy and clustered rainfall or causing rainstorms. Monsoon rainfall received at the northern part, situated at the base of the mountain front, is more than twice the monsoon rainfall received at the floodplain section in the south. Due to such variations of rainfall six rainfall zones may be found within a northsouth distance of 100 km and west-east distance of <50 km. High intensity rainfall received during rainstorms lead to flash floods in different parts of the Jaldhaka- Duduya watershed. Simple statistical techniques have been used to identify characteristics of rainfall within the watershed, for which both rainfall data collected by selected tea gardens and data collected from registered website of Indian Meteorological Department have been used . Parameters like seasonal and daily rainfall, average 24hour rainfall frequencies, maximum 24 hour rainfall have been used. Time series analysis of annual rainfall of some selected tea gardens of the area show little or no variation for the first decade (1923-1952), distinct rising trend during the second decade (1971- 2000) and finally, a clear decreasing trend for the third decade (2001-2019), which is further substantiated by calculation of standard deviation of decadal rainfall. Annual rainfall has decreased throughout the watershed, as proven by mean rainfall calculated for the post- 2000-s period. There is, thus, a change in rainfall pattern within the Jaldhaka- Duduya watershed; the prevailing change is increasing frequencies of rainstorms, occurring both in the piedmont and floodplain sections. Longitudinal profiles constructed for the Jaldhaka and the major rivers of the watershed reveal variations of relief and degree of concavity. Least square regressions were done to fit longitudinal profiles, showing elevation-distance data, which show concavity for all rivers and breaks of slope, indicating tectonic control, except Duduya, which originates from the piedmont terrace. The Streamlength Gradient Index (SLGI) developed by Hack was also used to calculate degree of structural control on the rivers, which indicate youthful stage for major rivers, except Duduya. Transects constructed across major rivers at selected sites and at selected time intervals, bring out preponderance of braiding activity in Jaldhaka, Daina and Rethi Rivers, with propensity of bank attrition and toe erosion, especially, following rainstorms or periods of clustered monsoon rainfall. Evidences of north- south shifting of the confluence of Jaldhaka and Daina is noted from satellite images and Google maps. Only River Duduya has a comparatively stable channel, with comparatively lower degree of bank erosion. Increased sedimentation within the channels of major rivers and their tributaries, specially rivers with source regions lying deep within the Bhutanese Lesser Himalayan zone causes increased braiding, accumulation of lag deposits within channels in the piedmont and alluvial fan sections, lying within Indian territory. This is found to occur due to unplanned mining activities, mainly within Bhutanese territory, gratuitous lifting of sand and gravel from beds of Daina and Rethi within Indian territory, resulting in steady raising of beds of both tributaries and the trunk river itself, increasing thus, the risk of floods, during periods of active or vigorous monsoon or during rainstorms. Rapid urbanization in and around the Jaldhaka- Duduya watershed, necessitating construction and refurbishment of communication network of the region, construction and extension of settlements and tea garden areas in upper catchment and source regions of rivers, have increased amount and frequencies of slope wash, slope failures and landslides, debris being transported downstream, choking smaller channels and further increasing sedimentation and braiding activities. All of these have led to fertile agricultural lands becoming flood- prone and barren for considerable periods. Thus, general land and environmental degradation throughout the watershed has set in, affecting the chiefly agrarian economy of the area. Hydrographs could, however, be constructed only for Jaldhaka, which is the main river of the watershed. It is observed, that, rainstorms lasting for two or three days at maximum, are capable of triggering peak discharge resulting in flood flows followed by a series of events, ranging from soil and riverbank erosion, or even avulsion, which decrease rapidly, almost immediately after rainfall decreases or stops altogether. Return period of floods with very high discharge has remained the same, but return period of floods with medium to moderately high discharge seems to be increasing during recent years. Risk of floods has increased during recent years due to environmental degradation, in spite of the changing rainfall pattern, that indicates somewhat decreased annual rainfall. Flooding and inundation have become annual phenomena, for bigger and smaller rivers alike. Popular measures of protection from floods, like construction of flood embankments have been successful, only initially. With increasing demand for regional development, need for improved transport and communication system, improved housing and certain amenities cannot be denied to local people. Sustainable development measures for regional development, with minimized effects of the delicate ecological balance are suggested for the Jaldhaka- Duduya watershed.Item Open Access Livelihood conditions of census town dwellers of Jalpaiguri District, West Bengal(University of North Bengal, 2023) Ali, Ershad; Sarkar, Bipul ChandraUrbanization is the process by which cities grow and population is concentrated in urban areas. The growth of census towns makes a notable contribution to the process of socio-economic and socio-cultural transition of dwellers. The separate recognition of census towns and statutory towns contributed to a better understanding of the urbanization pattern. In the new era of urban development, increasing urbanization has a direct impact on the demographic and socio-economic situation of statutory and census cities. Census Towns are the towns which are not legally registered areas and administer the area like a city, they are in rural revenue village, i.e., they are administratively in the rural area but their population has attained urban characteristics. The role of Census Towns (CTs) in the urbanization process in sub-Himalaya West Bengal as well as in the Dooars region is very crucial. It influences not only the rate of urbanization in this region, but also changes in land use and land cover as well as the sociocultural conditions of the study area. The CTs are helping to change the land use pattern of the sub-Himalayan regions of West Bengal. The extent and pace of urbanization have had a profound impact on the livelihoods and demographics of cities and CTs. The growth and expansion of CTs are directly influenced by the rate of urbanization and indirectly by the sociocultural changes in the study area. The present study is an attempt to assess the trend and growth of CTs more accurately and scientifically, the livelihoods and infrastructural development of the Census Towns accordingly, to identify the key issues disrupting the growth of CTs and the allocation of facilities and services to ensure a better socio-economic life of residents of census cities in the study area. In addition, it aims to examine various urban problems and provide some remedies. Jalpaiguri district is in the northeast of West Bengal. Geographically, the district is bordered by Alipurduar district to the east, Cooch Behar district to the southeast, Kalimpong district to the north, Darjeeling district to the north, and the Bangladesh International Border to the south and southwest. Geographically, Jalpaiguri district is located at 26⁰ 16′ to 27⁰ North latitude and 88⁰ 23′ to 89⁰ 8′ East longitude. The study is based on five main objectives: i) To find out the pattern and growth of CTs of the Jalpaiguri district, ii) To find the livelihood conditions of Census Town dwellers, iii) To scrutinize the levels of infrastructural development of the CTs of the study area, iv) To analyze the problems associated with the urban development of the CTs of the study area, v) To recommend the developmental strategy of the Census Town dwellers. Based on the selected objectives, there are four main hypotheses, namely i) The levels of urbanisation of the CTs are increasing over periods, ii) The socio-economic and socio-cultural status of the CTs are facing several challenges, iii) The infrastructural development of the CTs is inadequate, and iv) The problems associated with the urban development of the CTs are more in the case of large CTs and low in the case of small CTs. The first objective and hypothesis has been proved by the fact that the census towns share a significant percentage (almost half of the total urbanization) of the urbanization rate in Jalpaiguri district. While the concept of Census Towns (CTs) was introduced by the 1961 Census of India, the trend and growth of CTs varies from time to time. In 1961 the number of CTs in Jalpaiguri district was only 3, 3 in 1971, 4 in 1981, 6 in 1991, 4 in 2001 and 15 in 2011. The district's first Census Towns (CTs) were Maynaguri, Dhupguri, and Mal. The growth history of the Census Towns (CTs) of Jalpaiguri district shows the fact that there are no constant growth characteristics from the first decade of the CTs to the last few decades. Very slow, negative, and high growth rate of some CTs proves poor growth rate of district urbanization. But the past two decades, the growth rate is increasing due to the increase in the number of CTs of such a district. The 1961-1971 and 1971-1981 period was identified as a very slow growth period. The period from 1991 to 2001 has been identified as a negative growth period due to the declining of few census towns (CTs). The number of CTs was decreased from 6 in 1981 to 4 in 1991. The period from 2001 to 2011 has been considered a high growth period due to the emergence of several new Census Towns (CTs) over the past decade. The number of CTs was increased from 4 in 2001 to 15 in 2011. There are some important statistical tools such as growth indices, census town population balance sheets, annual exponential growth rate, etc. to measure the trend and growth of census towns. Urban geographers use these tools to measure urban growth. The same tools were also used in this study. Using the different measurement tools, it was found that the Census Towns (CTs) experienced low growth and experienced significant to high growth percentage over time from inception to the last census. The population balance for the census towns in the study area is calculated. The calculation shows that the growth rate and size classes of the CTs increase over time. The correlation coefficient was calculated and graphed to show the relationship between the total population size of CTs and the annual exponential growth, and it was shown that there is a very strong relationship between these two variables. The second objective and hypothesis has been proved by the fact that the social elements such as caste composition, sex ratio, marital status, age-gender structure, literacy status, health information, language, religion, etc. and economic elements such as economic activities, workforce composition, monthly family income, house type, housing conditions, basic housing amenities, household wealth, etc. were discussed in order to get an idea of the socioeconomic conditions of CT residents. The analysis revealed that the socio-economic characteristics of CT differ from town to town. The analysis has shown that the CTs in the tea and forest region have a higher concentration of the ST population in the northern part of the district than in the southern part. In terms of the sex ratio of Jalpaiguri district CT residents, Jalpaiguri district has an urban sex ratio of 943, slightly lower than the state average of 944 but higher than the national average of 926. The study shows that all CTs homogeneity and marriage similarities in the under 20s and over 30s age group, and the number of married women in the first age group at marriage is higher than that of men. On the other hand, the participation of men and women in marriage in the middle age group varies between CTs in the district. Looking at the total population as well as the population in different age groups in the CTs, the proportion of men in the entire district is comparatively higher than the proportion of women. The study also shows that residents use several common languages (Bengali, Hindi and Tribal) and a significant number of residents use other languages for their daily communication in the district's census towns. Several religious people also live in the CTs, even without any creed. Analysis was also conducted for common diseases of residents of the CTs across the district, and it was found that most of the residents face common diseases such as diarrhoea, fever, cough, hyperacidity, Covid-19, and some other diseases. There are also regional imbalances in the economic profile of census town residents. The census towns concentrated in the tea and forest region were found to have relatively lower economic status. Much of their workforce worked on tea plantations, resulting in a lower per capita income. The economically dependent population is also higher in these census towns, since the possibility of finding a job or other employment is comparatively low. Aside from these census towns, others have other difficult economic conditions. However, as the study shows, the overall economic profile of residents of census town is significantly low. Overall economic development is essential for a better economic livelihood. Residents had lower livelihoods throughout the study period. The differences between the Jalpaiguri district CTs were calculated to show the relationship between the various indicators of the CTs and their developmental scores, and it was shown that the maximal CTs range from the least developed to the moderately developed CTs. The third goal and hypothesis were supported by the fact that the spatial and temporal growth of CT and the improvement of urban infrastructure over time. The analysis revealed that the infrastructural characteristics of CT differ from town to town. The composite index was calculated to measure the infrastructural development of CTs. The spatial distribution of the CTs based on their infrastructural characteristics also showed some essential characteristics. The majority of the CTs had low to very low levels of infrastructure development in 1991 and 2001. The scenario of the CTs was upgraded in 2011, with the level being reduced from low to very low level of infrastructure development and upgraded to the level of high to medium level of infrastructure development. However, almost 50% of CTs belong to high-medium level and a little more than 50% of CTs belong to low to very low-level level infrastructure development. The fourth goal and hypothesis were supported by the fact the census towns and their dwellers suffer from many problems related to their daily livelihood. There is a lack of some basic facilities within the CTs such as access to clean drinking water, latrine and bathrooms, drainage, and separate kitchens, etc. All issues were discussed separately in every CT to understand the problem scenario. One of the main problems faced by CT dwellers is the lack of drinking water supply in the CTs. Due to the lack of proper water treatment facilities, a large percentage of households do not have access to clean water. Another problem is that to date, a large percentage of the homes of many CTs in the study area do not have latrines on their premises. This is because some of the CTs are in rural areas and a significant number of residents are uneducated. As for the proportion of households without separate kitchen facilities, in some CTs there are many households that do not have separate kitchens, particularly those whose occupants are economically vulnerable and dependent workers in the tea garden. In terms of the percentage of households without a drainage system, many households, almost all CTs, do not have a proper drainage facility in their home. Regarding the pH of the drinking water and the TDS of the water in the CTs, some of the CTs have a pH below 6.5, indicating the presence of acidic elements in the water, which non-potable according to the Bureau of Indian Standard. There is a CT where the TDS level in the water is below 50ppm, indicating it is not suitable for drinking. Regarding the noise level in the CTs, 73% of the CTs in the study area found an above-average noise level. There is a lot of noise pollution in the Jalpaiguri district CTs. Regarding the air quality (PM2.5 and PM10) in the CTs, the survey result shows that some of the CTs have a PM2.5 concentration higher than the safe limit, and regarding PM10, there are no CTs of the study area with more than 100g/m3. This means that the concentration of PM10 in the CTs is safe compared to PM2.5 in the atmosphere of the CTs across the district. There is a strong positive correlation between the total population and the concentration of PM2.5 and PM10 of the CTs. Regarding the air quality (TVOC and HCHO) in the CTs, the survey result shows that there is one CT that has TVOC above 0.2 mg/m3. The survey also shows that there are 3 CTs that have HCHO above 0.0123 mg/m3. Regarding the traffic volume in the CTs, the traffic load at the junction of all the CTs is heavy, and the CTs that are close to the highways have heavier traffic. On the other hand, the CT away from the highways have a low traffic load. Based on the average waiting time in minutes at the junction of all CTs, it shows that 33% of CTs have no waiting time for traffic at the junction. It is important to mention that the CTs located along the highways must wait a long time for traffic. Regarding the health infrastructure in the CTs, on average, most CTs have a lack of adequate health facilities in their CT area. As such, residents of CTs face several health challenges, particularly among the larger CT dwellers. Regarding the modern employment opportunities within the CT, the primary survey shows that almost all CT residents of any individual CT are dissatisfied with the availability of modern employment opportunities within the CT. They claim that the CTs lack modern facilities. Regarding solid waste, there is no system for collecting waste from residents. The dwellers of the CTs throw their daily rubbish everywhere. Therefore, the situation was getting worse day by day and it was observed that most respondents were dissatisfied with the solid waste in their CTs. The fifth goal has been proved by the various recommendations along with their problems within the CTs. Suggestions are made from the viewer’s own perspective. Since these are the Census Towns (CTs), the Gram Panchayats cannot provide adequate urban amenities for CT residents. The CTs should be declared as a Notified Area or Municipality. When the CTs become a municipal body, almost all the problems of the CTs will automatically disappear. As the municipality or notified area has its own laws and functions. Aside from that, the continued growth of CTs also creates some demographic issues. Therefore, the competent authority should take some necessary measures to minimize this problem. Education is another background that causes some breaks in the development of CTs. However, the literacy rate and level of literacy among CTs show spatial variation in the district. Some of the CTs have a standard literacy rate with a standard literacy level, but some of the CTs have a low literacy rate compared to the Indian urban literacy rate. Therefore, the government should need to set up more educational institutions within the CTs. Also, the existing health facilities in the CTs are not sufficient to cope with the health problems of the CT residents. So, to minimize these problems, the government should have to set up a health facility. Also, most of the CTs in theItem Open Access Status of irrigation and its impact on agriculture in Jalpaiguri District(University of North Bengal, 2021) Mandal, Manoranjan; Mandal, D.K,Item Open Access Assessment of the level of rural development in Jalpaiguri District, West Bengal(University of North Bengal, 2020) Das, Rituparna,; Lepcha Nee Lama, IndiraItem Open Access Socio-Economic status of tribal people in Mal Subdivision of Jalpaiguri District, West Bengal: a geographical analysis(University of North Bengal, 2017) Sarkar, Bipul Chandra; Roy, Ranjan,