Social,
Environmental & Economic Sustainability
Our analysis of the rank of the district
Backwardness : 415
Sex Ratio Rank : 108
(Rank one is least sex ratio - Cenus 2001)
HIV Category District : C
(HIV Sentinel Surveillance 2004 - 2006)
Disability : 266 (Census 2001)
Literacy Ratio : 367 (Census 2001)
Minority : Yes
Water : Flouride in Groundwater above permissible limits
Challenges of the district : Our research with local communities
Literacy among women in the district is less than
60%
Poverty is also high in the district.
Lack of large scale industries.
Brief About Dibrugarh District
Dibrugarh which is the headquarter of the district
derived its name from Dibarumukh. The name derived from the mouth(mukh)
of the river Dibaru or Dibru(Bodo word dibru,a blister) during
the reign of Siuhungmung, Pharsengmung Borgohain, Chao Siulung,
Kilong fought against the chetia king who was defeated in the
battle and surrendered before the Ahom King. Dibarumukh was a
renonwed encampment of Ahoms during Ahom Chutia War. Earlier Dibrugarh
was the District HQ of undivided Lakhimpur District.But now Dibrugarh
is a separate district having its own identity with the District
HQ still in Dibrugarh town itself.
GEOGRAPHY
Introduction
The Dibrugarh district extends from latitude and longitude.
It is bounded by Dhemaji district on the north, Tinsukia district
on the east, Tirap district of Arunachal Pradesh on the south-east
and Sibsagar district on the north and south-west. THe area stretches
from the north bank of the mighty Brahamputra, which flows for
a length of 95 km through the northern margin of the district,
to the Patkai foothills on the south. The Burhi Dihing, a major
tributary of the Brahamputra with its network of tributaries and
wetlands flows through the district from east to west.
Physiography
The Dibrugarh district is located in the north eastern corner
of the Upper Brahamputra valley south with an altitude ranging
between 99 and 474 meters. A major part of it is and extensive
plain formed by the Brahamputra and its major south bank tributary-the
Buri Dihing.
The Physiography of the district is constituted by a variety of
elements such as flood plain, beels and swamps, occasional highlands
and foothills of the Barail Range. The Brahamputra river is fairly
wide here (average width 10km).
The general gradient of the district of the area is from south-east
to north-west. The altitude of the south-easternmost corner covering
the Hapjan Parvat and Hilika Parvat of the Barail foot hills is
200m. The height decreases gradually from this corner to the mouth
of the Buri Dihing river where the altitude is 99 m. However the
northern belt of the area has a gentle slope from east to west.
The altitude of the eastern part is 115 m, while it is 99 m in
the western part. The average east-west slope is 152 cm per km.
Because of the relatively high slope and large volume of water,
the Brahamputra flows with a high velocity causing significant
bank erosion in the area. The earthquake of 1950 (magnitude 8.7
in the Richter scale, Poddar, 1952) accelerated the intensity
of bank erosion. The impact is alarming in the north of Dibrugarh
city and Rahmaria mouza.
The area may be divided into three distinct physiographic zones
stretching parallel to the Brahamputra river. These are : (i)
The active floodplain and 'charland', (ii) the middle plain; and
(iii) the southern foothills.
The first zone is an extensive and active floodplain of the Brahamputra.
The 'charlands'(sandbars) have also been included in this zone.
The charlands are suitable for grazing during the winter season.
The second zone is extensive because of the presence of fairly
large tributaries like the Dibru (which has now merged with the
Brahamputra) and the Buri Dihing through their headward erosion
added alluvial land substantially to the great plain of the Brahamputra.
This plain contains the rich belts of tea and rice cultivation.
All the mouzas excluding only Joypur are partly or wholely in
this zone. The highly meandered course of the Burhi Dhing here
has left cut off as many as 39 wetlands in the form of ox-bow
lakes and swamps.
The foothill zone on the other hand consists of isolated hillocks
interspersed with plain embayments extending into the Naga hills.
The high grounds of this zone composed mostly lateritic soils
are covered by tea gardens or dense forests. Located in this zone,
the Joypur Reserved Forest occupies an area of 10,666,08 hectares.
Rivers and Wetlands
On the northern margin of the district lies the river Brahamputra
which basically drains the whole area. The Brahamputra here is
very wide and braided. Near the Dibrugarh City the river is 10km
wide with a large number of sandbars. Till the great earthquake
of 1950 the north easternmost corner was drained by the Dibru
River. The Dibru was a main tributary of the Brahamputra the confluence
of it being at about 18km east of Dibrugarh City. By raising the
bed of the Brahamputra , the earthquake caused severe erosion
on its south bank and as a result the Dibru river got merged with
its master stream in Rahmaria mouza. Earlier, the interfluves
of the Brahamputra and the Dibru was on an average 6-8 km wide
within the district. Some of the inhabited villages like Sainaki,
Erasuti, Chabaru Kalioro, Sairsuti, Nepali Block, Mohmora, Charisuti,
Nepali South Block in between the Brahamputra and the Dibru, and
Rangajan, Laruparia Pathar, Guiphala Habi, Laruporia Saugaon,
Guiphala, Nagaon, part of Rahmaria Gaon, Gaharipathar, Piporatoli,
Nefafu grant on the south bank of the Dibru alongwith their fertile
agricultural land and forest cover were wiped away by the Brahamputra.
Now, Maijan stream, a tributary of the former Dibru has become
a tributary to the Brahamputra.
Buri Dihing river flows from almost east to west through the area.
It has many tributaries such as Digboi, Tingrai, Tipling, Telpani,
Deherang and Sessa in the north bank and Tipam and Disam in the
south bank. In addition to the tributaries of the Burhi Dihing,
there are three other tributaries of the Disang river( in Sibsagar
district) namely Gela Disam, Tiolo and Demow flowing mainly from
the Tingkhong mouza. Official reports , in fact suggest that Burhi
Dhing is the erstwhile Namphuk river. It flows for 90 km through
the Patkai Hills before it comes down to the foot hill zone. Thereafter
flowing in a south-west direction for 20km it meets the Khaikhe
and Meganton to form what is called Burhi Dihing. The Burhi Dihing
meanders through the plains facing Patkai Hills for a length of
50km and then enters into Joypur-Digboi low hill range. It then
comes out near Joypur to flow through the plains for a length
of 120km and ultimately joins the Brahamputra at about 32 km south-west
of Dibrugarh city.
Wetlands
Like any other parts of Assam, the area is endowed with extensive
water resources. The district possesses a large number of wetlands
of varying sizes. The larger ones are popularly know as beel,
while the marshes and swamps are generally known as jalah, doloni,
pitoni, doba, etc. In some areas, the beels are referred to as
gadang. However, all these features may be include under the comprehensive
term ' wetland'. The wetlands may broadly be divided into two
categories : the lake-like ones , i.e beel with clear wide-spread
water area and the others i.e. swamps and marshes covered by weeds,
grasses, etc.
Both the beels and the swamps are geomorphologically, ecologically
and economically very important features. These comprise a major
component of the area's ecology. The beels are traditionally used
as natural fisheries. Even today, the beels produce more fish
per unit area than any many other man-made fisheries. A large
number of beels are connected with the rivers by one or more feeder
channels. These feeder channels are lifeline of such water bodies.
Climate
Being located on the north of the latitude and with its unique
physiographic elements, the area experiences subtropical monsoon
climate with mild winter, warm and humid summer which may be designated
as CWB (Borthakur,1986). Rainfall decreases from south to north
and east to west in the area. The average annual rainfall of the
Dibrugarh city in the north is 276 cm with a total number of 193
rainy days, while at Naharkatia in the south, it is 163 cm with
147 rainy days. The temperature generally decreases from south
to north. The average annual temperature in Dibrugarh and Naharkatia
is 23.9 C and 24.3 C respectively. Located on the bank of the
Brahmaputra, the Dibrugarh city experiences mild climate with
low temperature and high rainfall as compared to Chabua in the
east and Moran in the west. The average annual temperature in
Chabua and Moran is 28 C and 32 C respectively. Rainfall records
show a decreasing trend towards east and west of Dibrugarh city.
The annual amount of rainfall in Chabua and Moran is 250 cm and
171 cm and 171 cm respectively. On the basis of the climatic characteristics
such as distribution of temperature, rainfall, rainy days, humidity,
presence of fogs and thunderstorms, the climate of the area may
be classified into four seasons :
(a) winter, (b) pre-monsoon, (c) monsoon and
(d) retreating monsoon
Winter
The winter covers the months of December, January and February.
In this season, fair weather prevails occasionally associated
with fogs and haze. December and January are the driest months
and January is the coldest. The minimum temperature ranges between
8 C and 10 C and the maximum between 27 C and 29 C. The average
rainfall in the season is 20 cm.
Pre-Monsoon
The months of March, April and May constitute the pre-monsoon
season. From March the land surface gets steadily heated and the
temperature starts rising. Strong convection develops due to the
local depressions formed especially in the afternoon. The nor'westers
locally called Bordoichilla appears during the period. Rainfall
ranges between 59 and 160 cm and maximum temperature ranges between
28 C and 32 C. This season is, in fact, a transitional phase between
the dry cool winter and the warm moist monsoon.
Monsoon
With the onset of monsoon in early June, heavy rainfall occurs.Widespread
low clouds and high humidity together maintain almost uniform
temperature over the area. The maximum temperature ranges between
33 C and 37 C. The average annual rainfall during the period is
300 cm. The occurrence of thunderstorms is the most conspicuous
characteristics of the monsoon weather. This is the season of
dominant agricultural operation in the area.
Retreating Monsoon
The monsoon withdraws from the area in the last week of September
or first week of October. The cool north-easterly winds originating
over the lofty mountains of the Arunachal himalayas brings the
temperature down. The orographic low is replaced by high pressure
and a flat pressure gradient occurs. Rainfall decreases abruptly
and the sky becomes progressively clear. Sunny days prevail till
the end of November.The CWB climate thus has a profound influence
on the economy and lifeof the people of the area. It is most suitable
for the cultivation of a variety of grain and horticultural crops.
Soil
The soils of the area are basically the products of the fluvial
processes of the Brahmaputra and its tributaries. The plains are
composed of alluvium which may be classified as new and old. The
new alluvium varies mostly from clayey to sandy loam in texture
and is slightly acidic in reaction. it is deficient in phosphoric
acid, nitrogen and humus, but rich in lime and potash. It is found
in the vast plain of the district along the river valleys, especially
in their lower courses.The old alluvium on the other hand occurs
in the upper and middle parts of the valleys. It occurs mainly
in Joypur,Tipling, Kheremia and Tengakhat mouzas in the form of
terrace deposits. These deposits contain alternating beds of pebbles,
gravel or boulder with loose sand and clays. In certain parts,
both the old and new alluvium are so combined that it is difficult
to distinguish them.
The old alluvium has relatively high percentage of acid and soluble
Mg accompanied by Ca in general, its HCL soluble material contents
are lower and the percentage of MgO is higher. The pH value ranges
between 4.2 and 5.5 with very low quantity of exchangeable calcium
which varies from 0.1 to 5.0 mg per 100 gms of soil
The new alluvium is less acidic as compared to the old alluvium.
Its pH value varies from 5.5 to 9.0. These soils are rich in PO4'K
and Ca (6 to 21mg per 100 gms of soil), but its N2 content is
somewhat low, being 0.1percent .
Tea is abundantly grown in the old alluvium as it has high percentage
of acid. The tea estates are located over relatively high lands
covering mainly the mouzas of Chabua, Bogdung, Rahmaria, Tengakhat,
Tipling, Kheremia,Gharbandi, Lahoal, Moderkhat, Mancotta, Jamira,
Joypur and Tipling with discernible slopes containing both old
and new alluvium. Heavy clays, with high percentage of N2 are
suitable for rice cultivation. The silty river banks lying in
Lengri, Khowang, Mancotta and Larua are favourable for pulses
and vegetables.
The river banks bear texturally three types of soil: sandy loam,
loam and clayey loam. These favour the cultivation of winter rice,
mustard, pea, vegetables, etc. Of the total river bank area, 82.0
percent is arable, 7.0 percent is non arable land and 11.0 percent
is not available for cultivation. As per the reports of the National
Watershed Development Project for Rainfed Areas (NWDPRA) , 1991-92,
soils of the flood plain may be classified into four classes :
Land having moderate limitations and good land which is subject
to wind and water erosion and can be cultivated with some corrective
measures, Second, Land having moderate limitations and good land
with excessive sand structure, gravel and stony conditions that
can be cultivated with some corrective measures), Third, land
having severe limitations like excessive wetness or too much overflow
where regular cultivation is possible if hazards are removed and
well treated by corrective measures and fourth land not suitable
for cultivation due to excessive overflow or water-logging condition
which can not be drained out and can be used only for fishing
(Fig.2.4). The percentage strength of area under the these classes
are 82.0, 8.0, 4.0 and 6.0 respectively.
