2.1 Study Area: Location
The Climate Change vulnerability assessment was conducted in rural areas of nine Southwestern districts of Bhutan falling outside the country's Protected Area system (Fig. 1). The nine districts further comprise 85 administrative blocks known as Gewogs, which are the smallest unit of administration in the Bhutanese governmental structure. The nine districts are Samtse, Chhukha, Sarpang, Tsirang, Dagana and Zhemgang, Thimphu, Paro and Haa, covering a total area of 9835 km2, which is approximately 27% of the total geographical area of the country. Thimphu, Paro and Haa districts are in the extreme Western part of the country with a predominantly temperate climate, while the remaining districts are located along the lower foothills of the southern belt with a predominantly subtropical to tropical climate. With average elevation ranging from 97 to 5720 masl, the landscape cuts across all the six major agro-ecological zones of Bhutan, from wet subtropical in the south with relatively high rainfall to dry alpine meadows which remains mostly under snow cover around the year. The variation in climate, weather and forest ecosystems along the landscape is significant due to changes in microclimates along the landscape.
2.2 Land Use Types
With about 83% of the total landscape area under forest cover, forest is the major land use type in the study area. Only about 5.6% of the total landscape area is under agriculture, comprising both wetland and dry lands. About 1% of the total landscape area is under water bodies, including rivers, streams, lakes, water catchment areas and wetlands (NFI, 2023). With forest as the major land use type in the landscape, it comprises of eight different types of forest, viz.: Warm Broadleaved Forest, Cool Broadleaved Forest, Subtropical Forest, Fir Forest, Evergreen Oak Forest, Hemlock Forest, Blue pine Forest and Chirpine Forest. Warm Broadleaved Forest is the predominant forest type in the landscape, followed by Cool Broadleaved Forest and Subtropical Forest (Table 1).
Table 1
Land use types and forest types of the study areas
Land use Types
|
Area (Ha)
|
%
|
Forest Types
|
Area (Ha)
|
%
|
Forests
|
815886.23
|
83.1
|
Warm Broadleaved Forest
|
265391.03
|
33.67
|
Shrubs
|
62223.24
|
6.3
|
Cool Broadleaved Forest
|
136549.3
|
17.32
|
Cultivated Agriculture
|
55423.52
|
5.6
|
Subtropical Forest
|
127064.75
|
16.12
|
Meadows
|
16862.64
|
1.7
|
Fir Forest
|
89029.4
|
11.29
|
Alpine Scrubs
|
9895.93
|
1
|
Evergreen Oak Forest
|
79788.41
|
10.12
|
Water Bodies
|
9615.62
|
1
|
Hemlock Forest
|
45128.1
|
5.73
|
Rocky Outcrops
|
4699.44
|
0.5
|
Blue Pine Forest
|
42367.95
|
5.37
|
Built up
|
4110.53
|
0.4
|
Chirpine Forest
|
2927.49
|
0.37
|
Landslides
|
1583.1
|
0.2
|
|
|
|
Snow and Glacier
|
572.84
|
0.1
|
|
|
|
Non-Built up
|
354.5
|
0
|
|
|
|
Forests play a vital role in the livelihood of the landscape population and are intrinsically intertwined with the social, cultural and traditions of the communities. The landscape has a total of 357 Community forests, which are solely managed by the communities to meet their tangible and intangible livelihood needs (DoFPS, 2022).
2.6 Methodology
2.6.1 Climate Vulnerability Assessment and Conceptual Framework
The concept of climate change vulnerability is complex and multifaceted, encompassing exposure, sensitivity, and adaptive capacity (Laitonjam, 2018), leading to a multitude of definitions and interpretations of the term vulnerability with no one universally accepted definition of vulnerability (MoEFC, 2014). Vulnerability is influenced by a range of factors, including environmental, socioeconomic, institutional, and political structures (Pricope et al., 2013). The one-size-fits-all vulnerability label is not sufficient. Measuring vulnerability is particularly misleading, as this is impossible and raises false expectations. It is important to note that vulnerability is a theoretical concept and cannot be directly measured or observed (Hinkel, 2011). The only consensus that seems to exist is that vulnerability is bound to a specific location and context. Further, all vulnerability assessments are relative and not absolute (Adger et al., 2003). The IPCC Third Assessment Report (TAR) describes vulnerability as “The degree to which a system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes” (IPCC, 2003). This concept of IPCC is adopted for the purpose of this assessment, which was used for such similar studies (Hahn et al., 2009; Kumar et al., 2016; Lung et al., 2013; Metzger et al., 2006).
CV = f (E, S, AC) ………………………………………………………………………... Eq. (1)
Where CV (Vulnerability) is expressed as a function of exposure (E), sensitivity (S) and adaptive capacity (AC) (Brooks et al., 2005; IPCC, 2003; KC et al., 2015). It is used primarily to refer to the vulnerability of climate change impacts.
Exposure is defined in these reports as the nature and degree to which a system is exposed to significant climatic variations. Sensitivity is the degree to which a system is affected, either adversely or beneficially, by climate-related stimuli. The effect may be direct, such as a change in crop yield in response to a change in mean, range, or variability of temperature, or indirect, such as damages caused by an increase in the frequency of coastal flooding due to sea level rise (Brooks, 2003). Adaptive capacity is the system's flexibility to adjust to climate change and cope with the consequences. The system's capacity to adapt to the system depends on the ownership and access to assets (Piya et al., 2016). Vulnerability is influenced by adaptive capacity, which has an inverse relation with vulnerability (Giupponi et al., 2019). The conceptual framework for assessing vulnerability and developing adaptation measures is represented in Fig. 2.
Each district was considered as the system of interest for which climate change vulnerability was assessed. The individual blocks (Gewogs) of the districts were selected as the assessment’s unit of measurement. Three conceptual approaches of vulnerability are typically used: socio-economic (Neil Adger, 1999), biophysical (Füssel & Klein, 2006) and integrated approaches (Nelson et al., 2010; O’Brien et al., 2004; Piya et al., 2016). The socio-economic approach involves analysis of society's social, political and economic aspects (Choden et al., 2020). It is associated with the well-being of individuals, communities and society (UNISDR, 2004). Thus, this method was employed in this study
2.6.2 Selection and description of indicators
Vulnerability assessments can be qualitative or quantitative, which include indicator-based and econometric-based methods (Choden et al., 2020; Gerlitz et al., 2017; Maiti et al., 2015). The ‘econometric method’ analyzes the level of vulnerability of different social groups using household-level socio-economic survey data, while the ‘indicator method’ selects the indicators from potential indicators and systematically combines them to indicate the level of vulnerability (Deressa et al., 2008). Numerous studies used ‘indicator method’ to assess social vulnerability to climate change (Brooks, 2003; Choden et al., 2020; Hahn et al., 2009; Maiti et al., 2015; Nelson et al., 2010; Piya et al., 2016). Similarly, the indicator-based method was applied for the present assessment. The indicators for exposure, sensitivity, and adaptive capacity were identified and listed in the literature on similar studies (cf. Maiti et al., 2015; Choden et al., 2020). Consultations with experts from Ugyen Wangchuck Institute for Forestry Research and Training and field officials of the study area were also held in a series of meetings and workshops to finalize the indicators. The indicators were thoroughly discussed based on their potential impacts and contribution to exposure, sensitivity and adaptive capacity.
Following O’Brien et al. (2004), exposure is represented as “either long-term changes in climate conditions or by changes in climate variability, including the magnitude and impacts of extreme events.” This definition includes climate change and extreme events, which form the central focus of this study. Perception of historical changes in climate variables, occurrence of extreme events and its impacts were taken as the indicator for the exposure (Piya et al., 2016). The climatic variables include temperature extremes and their impacts, shifts in rainfall seasonality, and occurrence of extreme events. Climate-related extreme events are landslides, flashfloods, Glacial Lake Out Burst Floods (GLOF), windstorms, occurrence of seasonal droughts and heat waves. Large scale destruction of agricultural crops due to windstorms is also reported from most parts of the study area annually. Since most of the households in the study area practice rainfed agriculture, seasonal droughts caused by delay or absence of rainfall in monsoon seasons significantly impact agriculture food production, particularly paddy cultivation, one of the main staple foods in the study area. These indicators indicate the extent of exposure of the communities as a whole and are applicable across multiple sectors.
Sensitivity is measured by the “degree to which a system is modified or affected by an internal or external disturbance or set of disturbances” (Gallopin, 2003). This approach to sensitivity considers the cumulative impacts of past climate hazards on livelihoods as a proxy for future sensitivity, as the households facing higher impacts are the ones that will be more sensitive in the future. For this study, climate-sensitive sectors like agriculture, water, livestock, forest, health, and infrastructures were used to determine their sensitivity. Decrease in crop yield, increase in incidences of pests and diseases, increased infestations by invasive weeds both in agricultural and forest lands, change in forest cover and compositions over the last ten years, changes in the availability (volume) of irrigation and drinking water, change in the wildlife population, death of family members due to vector or water-borne disease represent sensitivity for the purpose of this study. It is hypothesized that higher impacts of past climatic disasters increase the sensitivity of households and, more so, to poorer sections of the community. Changes in wildlife populations were considered sensitivity indicators, specifically from the point of view of human wildlife conflict (HWC). Several studies have shown that climate change is one of the drivers of HWC, causing changes in plant phenology and shifts in habitat. A study by Abrahms (2021) highlighted that climate change impacts the availability of resources, thereby causing the congregation of wildlife and people to crowded spaces, causing conflicts.
The adaptive capacity of the households was considered as the summation of five types of livelihood assets physical, human, social, natural and financial (Gerlitz et al., 2017; Maiti et al., 2015; Piya et al., 2016). A diversified asset would allow for substitution among the assets to switch from one livelihood activity to another with the changing impacts of climate change (Piya et al., 2019a). Physical assets are represented by four indicators viz, access to socio-economic facilities, access to basic household facilities, access to road, and communication media. Access to these facilities enhances the adaptive capacity of households to cope with the impacts of climate change. The ownership of a mobile phone/radio/television increases adaptive capacity through access to weather-related information. Access to roads is assumed to be proportionately related to adaptive capacity as households located far from roads will be at a disadvantage for reasons such as lack of opportunity for income generation due to lack of markets or inability to access service centers such as hospitals at a time of emergency (Piya et al., 2019). There are four indicators under human assets viz, literacy of the head of the household, vocational skills of the household members, gender of the household head and awareness of climate change adaptation. Labor exchanges, which is an age-old practice followed in rural villages, increase the adaptive capacity as it not only enhances the social bond in the community but also meets the labour requirements at minimal costs as opposed to hiring and mechanization. There are seven indicators under natural assets: household landholding, the status of forest and wetland conditions surrounding the households, availability of different types of forest resources, availability of alternative sources of drinking and irrigation water and food self-sufficiency of the households, all of which increases the adaptive capacity of households. Financial assets include access to credit facilities and availability of savings. A total of 6 indicators for exposure, 14 indicators for sensitivity, and 21 indicators for adaptive capacity were used to assess the vulnerability (Table 4).
Each finalized indicator was then quantified by providing and deciding on a measurable parameter. Most indicators were given a score of 0 to 2 based on the impacts caused to the communities. The scoring was decided jointly through consultation with field officials representing respective districts. A detailed description of the indicator is given in Table 4.
2.6.3 Vulnerability Analysis
The latent variables (Exposure, Sensitivity, and Adaptive capacity) were captured based on indicators by constructing a confirmatory factor analysis (CFA) model using the lavaan package in R. CFA was used for this study as all the variables are categorical. One factor CFA was employed with the assumption that each latent variable associated with indicator variables is a reliable estimate measure of respective latent variables. All the indicators used to estimate the latent variables are fundamental elements in a CFA, and the covariance between the observed variables forms the fundamental components of the CFA. The observed population covariance matrix 𝛴 is a matrix of bivariate covariance that determines how many total parameters can be estimated in the model. The model implied matrix 𝛴(𝜃) has the same dimensions as 𝛴. The model-implied covariance is defined as:
𝛴(𝜃) = 𝐶𝑜𝑣(𝑦) = 𝛬𝛹𝛬′ + 𝛩 𝜖 ……………………………………………………………. Eq. (2)
This means that theta 𝛩 is composed of parameters 𝛬, 𝛹, 𝛩, which corresponds to the loadings, the covariance of latent variables and the covariance of residual errors. For estimation of this model, the marker method was used, whereby it fixes variance of each factor to one but freely estimates all loadings. The constructed model was diagnosed for robustness using RMSEA and observed the value of 0.061 and a P-value less than 0.001, indicating that the model is robust. The robust model is used to predict latent variable values for each observation. The predicted values are then normalized to bring the values within the comparable range. The min-max method was used for data normalization, where the formula (Value-Min)/(Max-Min) was used. The following formula was used to determine the vulnerability index:
𝑉𝑢𝑙𝑛𝑒𝑟𝑎𝑏𝑖𝑙𝑖𝑡𝑦 (𝑉) = 𝐴𝑑𝑎𝑝𝑡𝑖𝑣𝑒 𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 (𝐴𝐶) − (𝐸𝑥𝑝𝑜𝑠𝑢𝑟𝑒 (𝐸) + 𝑆𝑒𝑛𝑠𝑖𝑡𝑖𝑣𝑖𝑡𝑦(𝑆))
The overall vulnerability index facilitates inter areas comparison. A higher value of the vulnerability index indicates lower vulnerability. A negative index value indicates the net effect of adaptive capacity, exposure and sensitivity (Maiti et al., 2015).
Table 4: Description of indicators used in the assessment
Component
|
Indicator
|
Description and Scoring of the Indicator
|
Unit
|
Relation
|
Exposure
|
Extreme Temperature
|
Occurrence of temperature extremes (1 = Experienced either heat or cold; 2 = Experienced both head and cold; 0 = Have not experienced it/have no idea)
|
Ordinal Value
|
+
|
Extreme Temperature Impacts
|
Impacts of extreme temperature experienced (0 = No impacts are experienced; 1 = 1–3 impacts are experienced; and 2 = if more than 3 impacts are experienced)
|
Ordinal Value
|
+
|
Rainfall Seasonality
|
Shift in rainfall seasonality (0 = No occurrence or no information provided; 1 = Occurred)
|
Ordinal Value
|
+
|
Changing rainfall seasonality impacts
|
The number of impacts experienced due to changes in rainfall seasonality (0 = No impacts are experienced; 1 = 1–3 impacts are experienced; and 2 = 3 or more impacts are experienced)
|
Ordinal Value
|
+
|
Occurrence of extreme events
|
The number of extreme events occurred (0 = No occurrence; 1 = 1–3 extreme events occurred; and 2 = if more than 3 extreme events occurred).
|
Ordinal Value
|
+
|
Impacts of extreme events
|
The number of impacts experienced due to extreme events (0 = no impacts are experienced; 1 = 1–3 impacts are experienced; and 2 = more than 3 impacts are experienced)
|
Ordinal Value
|
+
|
Component
|
Indicator
|
Description and Scoring of the Indicator
|
|
|
Sensitivity
|
Crop Yield
|
Decrease in crop productivity (0 = increase in crop yield; 1 = No change; 2 = decrease in crop yield)
|
Ordinal Value
|
+
|
Pest Diseases
|
Occurrence of pests and diseases (0 = no information on occurrence; 1 = 1–2 types of pests and disease experienced; 2 = 3 or more types of pests and disease experienced)
|
Ordinal Value
|
+
|
Invasive Weeds
|
Types of invasive weeds observed (0 = no information or its types; 1 = 1–2 types observed; 2 = 3 or more types observed)
|
Ordinal Value
|
+
|
Invasive Weeds Occurrence
|
Type of land affected due to occurrence of invasive weeds: (1 = either agriculture land or forest land; 2 = both types of land affected; 0 = No occurrence observed either in agricultural land or forest land)
|
Ordinal Value
|
+
|
Drinking Water
|
Change in drinking water volume (2 = dried up; 1 = decreased; 0 = no change or uncertain)
|
Ordinal Value
|
+
|
Irrigation Water
|
Change in irrigation water volume (2 = dried up;1 = decreased; and 0 = no change or uncertain)
|
Ordinal Value
|
+
|
Forest Cover
|
Change in forest cover (2 = decreased; 1 = no change; 0 = increased)
|
Ordinal Value
|
+
|
Forest Composition
|
Change in forest composition (2 = change observed; 1 = uncertain; 0 = no change)
|
Ordinal Value
|
+
|
Wildlife Population
|
Change in wildlife population (2 = increased; 1 = no change; 0 = decreasing)
|
Ordinal Value
|
+
|
Vector Diseases
|
Occurrence of vector borne disease (2 = increased, 1 = no change; and 0 = decreased)
|
Ordinal Value
|
+
|
Water Diseases
|
Occurrence of water borne disease (2 = increased; 1 = no change; and 0 = decreased)
|
Ordinal Value
|
+
|
Family Fatality from Water and Vector Diseases
|
Family fatality due to water and vector diseases (1 = yes; and 0 = no)
|
Ordinal Value
|
+
|
Pastureland
|
Pastureland conditions (2 = degraded; 0 = improved (0); 1 = no change or uncertain)
|
Ordinal Value
|
+
|
Impact on Infrastructure
|
Number of infrastructures impacted due to climate hazard (1 = one; 2 = two or more are impacted; and 0 = if none are impacted)
|
Ordinal Value
|
+
|
Component
|
Indicator
|
Description and Scoring of the Indicator
|
|
|
Human Asset
|
Household head literacy
|
Literacy of household head (0 = illiterate; 1 = secondary education, including monastic education; and 2 = bachelor's degree and above)
|
Ordinal Value
|
+
|
Vocational Skill
|
Vocational skills of household members (0 = none or zero; 1 = 1 to 3 skills; and 2 = 3 or more skills)
|
Ordinal Value
|
+
|
Gender of Head of the Household
|
Gender of the Head of the Household (1 = male and 0 = female)
|
Ordinal Value
|
+
|
Climate Awareness
|
Awareness on climate change and adaptation (0 = not aware; 1 = aware).
|
Ordinal Value
|
+
|
Waste Awareness
|
Awareness on waste management (2 = aware or moderately aware; 1 = limited awareness; and 0 = not aware)
|
Ordinal Value
|
+
|
Social Asset
|
Group membership
|
Membership in social group (1 = yes; and 0 = No)
|
Ordinal Value
|
+
|
Farm Labor
|
Availability of farm labour types (0 = when no or atleast 1 type of labor is available; 1 = 2–3 types of farm labours available; and 2 = more than 3 types of farm labours available)
|
Ordinal Value
|
+
|
Group Membership Types
|
Membership to community group (0 = no membership; 1 = membership in 1–2 community groups; and 2 = membership in more than 2 community groups
|
Ordinal Value
|
+
|
Natural asset
|
Forest Status
|
Condition of forest in the locality (2 = good condition; 1 = uncertain; and 0 = degraded condition)
|
Ordinal Value
|
+
|
Wetland Status
|
Condition of wetland in the locality (2 = good condition;1 = uncertain; and 0 = degraded condition)
|
Ordinal Value
|
+
|
Forest Produce Type
|
Types of forest produce available (1 = 1–2 available; 3 = more than 3 types available; and 0 = if no produce is utilized or available)
|
Ordinal Value
|
+
|
Land Holding
|
Extend of landholding (0 = no land holding, 1 = landing holding from 1 acre to 3.45 acres; and 2 = > 3.45 acres land holding
|
Ordinal Value
|
+
|
Water Availability
|
Availability of drinking water (0 = acute water shortage; 1 = when it is available for 3 to 6 months; and 2 = availability all year round)
|
Ordinal Value
|
+
|
Alternative Water Source
|
Availability of alternative water source (1 = yes; and 0 = no)
|
Ordinal Value
|
+
|
Food Self- sufficiency
|
Food self-sufficiency (2 = complete self-sufficiency ;1 = partial or mostly self-sufficiency; and 0 = no self-sufficiency)
|
Ordinal Value
|
+
|
Financial Asset
|
Credit facility
|
Access to credit facility (1 = available; 0 = not available)
|
Ordinal Value
|
+
|
Savings
|
Availability of savings (2 = savings > Nu. 120,000; 1 = savings < Nu. 120,000; and 0 = having no savings)
|
Ordinal Value
|
+
|
Physical asset
|
Facility Access
|
Access to socio-economic facilities (0 = access to1-3 facilities; 1 = access to 3–4 facilities; and 2 = access to more than 4 facilities)
|
Ordinal Value
|
+
|
Household facility Access
|
Access to household facilities (0 = access to < 2 facilities; 1 = access to 3–4 facilities; and 2 = access to more than 4 facilities)
|
Ordinal Value
|
+
|
Road access
|
Access to types of roads (2 = paved road; 1 = unpaved road; and 0 = no access to road)
|
Ordinal Value
|
+
|
Communication Medium
|
Access to communication medium (1 = access to 1 medium, 2 = access to 2 or more medium; and 0 = no access to communication medium)
|
Ordinal Value
|
+
|