AHP based Flood Hazard Zonation and Risk Assessment in the Bhagirathi River Basin, India

Gourav Piyush, Kumar Rajesh and Gupta Akhilesh

Page No. 1-16

Bhagirathi River basin of Garhwal Himalaya has witnessed several devastating floods in the recent past. The aim of the study is to identify the flood vulnerable zones of Bhagirathi River basin with the help of multicriteria decision analysis (MCDA) based analytic hierarchy process (AHP) under geospatial environment. Saaty’s nine parameters based normalised arithmetic averages comparison matrix have been used to calculate the consistency ratio (CR). For this study, 0.06 CR value has been calculated that indicates the realistic degree of consistency in the pair-wise comparison study. The flood hazard zonation and risk assessment map of Bhagirathi River basin have been prepared on the basis of rank and weight based on CR values. The risk analysis shows that 5.11% area of the river basin is falling under a very high-risk zone whereas 19.90 % area is found under high risk zone. Most of the agricultural land (89%) is found under high to very high-risk zone; contrary to the agricultural status the maximum forest cover (99.24 %) falls under moderate flood risk zone.

The demography analysis says that out of 690 villages, 616 (89 %) villages with 164,400 (80 %) populations are falling under high to a very high-risk zone. Educational institutions (831 with 81.2 % share), hospitals/health centres (153 with 91.1 % share), and road (1237.41 km with 91.3 % share) are falling under high to very high flood risk hazard zone. There are 5 operational and 21 under construction hydropower projects making a total capacity of 4163 MW Bhagirathi River basin. These projects come under high risk during flooding. The results of this study can be very useful to the policy makers and government organizations for flood forecasting, monitoring, risk assessment, preparedness and rescue planning.

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Attenuation of seismic coda waves in Sikkim Himalayas, India

Singh Priyamvada and Kumar Sushil

Page No. 17-23

Vertical components of digital wave forms are processed for the attenuation characteristics of seismic coda waves. These wave forms are recorded in Sikkim area and total 108 digital waveforms have been analysed for estimation of Q_c values at central frequencies ranging from 2-16 Hz using a coda window of 25 s starting at twice the travel time of S-wave arrival. Single backscattering model of Aki is used for determining the〖 Q〗_c. The mean value of Q_c depends on frequency which is varying from 139±57 at 2.0 Hz to 1220±287 at 16 Hz.

The frequency-dependence average Q_c relationship (Q_c=Q_o f^n ) has also been obtained for the region as Q_c=(71.7868 ± 4) f^((1.04040± 0.05) ). The frequency dependent power law fit also indicates that the obtained average Qc values are strongly dependent on frequency and region is seismically and tectonically active. Obtained Q_c values in this study are significant for seismic hazard analysis.

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Disaster and quality of life: An example from Assam, India

Das Daisy

Page No. 24-31

Flood is a major environmental problem in India. This study tries to examine flood affected quality of life (QOL) in the State of Assam situated in the northeastern part of India. The QOL that we are discussing refers to experienced life quality during flood. We examine the effectiveness of institutions during flood and how it affects life quality. This study is based on a field survey conducted in two flood prone districts of Assam. Two stage sampling has been applied for collecting primary information. There are altogether 400 samples selected by simple random sampling. The study finds that exposure to flood negatively affects QOL.

However, social safety net and structural adaptation may help people. To prepare the community to live with flood, this study recommends coping and adaptation measures along effective social safety nets. The findings of the study identify measures which may be given special emphasis in flood prone areas.

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Impact of Climate change on Cryosphere-Atmosphere- Biosphere Interaction over the Garhwal Himalaya, India

Ahmad S.

Page No. 32-38

A long-term relationship among nighttime Land Surface Temperature (LST), Snow Cover Fraction (SCF), NDVI (Normalize Difference Vegetaion Index) and AOD (Atmospheric Optical Depth) have been conducted in different eco-regions of the Garhwal region, central Himalaya using MODIS monthly images. The trends were determined using linear regression methods for different seasons and regions. It is observed that the trends of the nighttime LST are similar between outer and higher Himalaya because of similar abundant free rock faces.

The enhanced warming associated with precipitation resulted in change in temporal character of NDVI and SFC. The glaciers recession is leading friable fresh moraine and caused to more availability of dust in the higher Himalaya than middle Himalaya. The trajectory of HYSPLIT model suggests higher rate of increase in AOD at higher Himalaya than in the middle Himalaya.

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Climate Change, Natural Resource Degradation and Marginalisation of Biodiversity Dependent Communities: An Evidence from a Tribal Context in Koraput District of Odisha, India

Rath Jyoti Prakash and Jena Damodar

Page No. 39-45

Tribal contexts are endowed with natural resources and rich biodiversity which offer variety of services including livelihoods to the local inhabitants. It is reported that there has been a symbiotic relationship between the indigenous community especially tribal and biodiversity. Their dependency includes collection and sell of minor forest produces like honey, tubers, fruits, mushrooms and semi-processed goods like brooms, leaf plates, incense latex, cultivation with conservation and fodders. The nature and extent of dependency on forest biodiversity varies with socio-economic background of the households. Unfortunately, a section of these dependent households is reported to be socio-economically marginalised. They are characterised as landless or marginal landholders.

However, they are found to have wisdom and wealth of knowledge on biodiversity as they have been frequently interacting with it from generations. The nature and extent of biodiversity services found to be declined over the years making the dependants further marginalised. With this backdrop, this study attempts to answer the following questions: (1) Who are these households that are primarily dependent on biodiversity-based livelihoods? (2) How does the loss of biodiversity due to natural resource degradation and climate change induce them to be marginalised?

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Flood Inundation Mapping using Synthetic Aperture Radar (SAR) Data and its impact on Land Use /Land Cover (LULC): A Case Study of Kerala Flood 2018, India

Maniruzzaman Sk, Balaji S. and Sharma S.V. Sivaprasad

Page No. 46-53

The frequency of disastrous flood is gradually increasing in India from last few decades. The intensity of flood not only can lead a country to become economically weak but also it can trigger poverty and malnutrition as a long-term effect. Kerala flood (August 2018) is one of the most noticeable disasters which devastated the infrastructure, agriculture, ecosystem as well as human lives. Due to extreme precipitation (more than 758.6mm) in two stages (8th – 10th and 14th – 19th August), Kerala experienced the catastrophic flood. In the present study, an attempt has been made to map the entire flood inundated area and to assess its overall damage on Land Use/Land Cover (LULC) in Kerala State, India.

High resolution Synthetic Aperture Radar (SAR) images (ALOS PALSAR and TerraSAR – X) were used to demarcate the flood inundation area and IRS LISS-III images was used to estimate the flood damages on LULC. The study reveals that the impact of flood is highly notable at Alappuzha district and Kottayam district with an area of 7625.36 hec and 4003.05 hec respectively. Further, 3400.12 hec of plantation/orchard and 2324.63 hec of double / triple crops were extremely damaged by the flood. Thus, the results of the present study will help to understand the influence of flood on LULC and to develop necessary precautions for Disaster Risk Reduction in future.

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The Earthquake Risk Management Model based on Sasak’ Local Wisdom

Adi Fadli and Masnun

Page No. 54-61

The aim of this study is to map the concepts of local knowledge and experience from the people of Lombok related to the concept of earthquake disaster mitigation and to produce a new model of earthquake mitigation based on Sasak’s local wisdom. The research methodology used Participatory Action Research (PAR) method with Participatory and Rapid Rural Appraisal as the data collecting technique. The results proved that the concept of local knowledge and experience of earthquake disaster mitigation had been passed down from generations of ancestors consisting of pre-disaster (customary and religious rituals and earthquake-resistant design of Sasak house construction).

Moreover, earthquake mitigation is conducted by early evacuation by sounding slit drum (Kul-kul) as an alarm to gather the community in Bale Agung. While post-earthquake is conducted by customary rituals such as Tolak Bahla, religious rituals are with reciting prayers for salvation. House construction known as Bale Bedeq or Bale Balak is made of woven bamboo, wood or boards. The earthquake mitigation model of Sasak’s local wisdom consists of 3 phases including pre-earthquake mitigation (customary and religious rituals, house construction), when an earthquake strikes and post-earthquake mitigation.

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Role of Social Capital in Building Disaster Resilience

Singh Akanchha

Page No. 62-66

Social capital is a rather old concept, but it has entered academic and policy debates only in the last two decades. The notion of social capital is pivoted around societal relationships. It gets manifested and reinforced via social networks, civic engagement, norms of reciprocity and bonds of trust. Experience of disaster in various countries suggests that civic networks established immediately after disasters in pursuit of collective goals relevant to actual or potential disasters are extremely beneficial. In this background, it is important to understand the role of social capital in building disaster resilience.

Studies have highlighted the particular utility of social capital for women in post-disaster scenario which includes psychological rehabilitation, empowerment and overcoming the stigma of public assistance. The significance of social capital in resilience building can hardly be overemphasized. However, studies focusing on the same are very few in number. There is an urgent need to mainstream the concept of ‘social capital’ in disaster management and development planning discourse.

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