Social and ecological climate change vulnerability assessment in the Indus delta, Pakistan

Due to climate change impacts, arid and semi-arid areas of the world are at risk regarding water scarcity and land degradation (IPCC 2008). Pakistan has more than 220 million population, which ranks it the sixth-most populous country in the world. It is one of the most vulnerable countries to the impacts of climate change (Rasul et al. 2012), ranking the sixth country on the climate change vulnerability index. The erratic freshwater flows because of temporal and spatial variability in rainfall due to climate change are turning acres of fertile agricultural land into a wasteland and thus threatening the biodiversity of the major ecological zones of Pakistan. The incidents of frequent flooding and droughts in the country are also increasing with larger variability in monsoon rainfall patterns (Rasul et al. 2012). The Indus River is a lifeline of the country, and its flows are unpredictable, decreasing at a faster rate. It is expected that due to the changing climate scenario, the River Indus flows will further decrease. Hence, agriculture and food security in the country will suffer the most.

At the end of the current century, the expected rise in sea level is about 180 to 590 millimeters (Ninan & Bedamatta 2012). This rise will ultimately affect the Indus River delta, which is the seventh-largest delta in the world stretching over about 0.6 million hectares (Salik et al. 2016). The delta is said to be the most vulnerable to the climate change. It is reported that due to the construction of dams and reservoirs in the Indus River basin and diversion of excessive water for domestic, irrigation, and industrial purposes, fresh water supply to the Indus River delta is significantly decreased (Alamgir et al. 2015; Siyal et al. 2022). That has converted the fertile agricultural lands of the delta into salt-affected soils and fresh groundwater aquifers and surface water bodies of the area into brackish. The resulting seawater intrusion has also drastically affected the flora, fauna, and mangrove cover, threatened the biodiversity and badly affected the socioeconomic conditions of the community living in the delta (Alamgir et al. 2015; Laghari et al. 2015; Thomas 2015; Peracha et al. 2017).

Furthermore, residents of the Indus delta have numerous difficulties. Most of the places that were once thriving farming, fishing, and commercial networks have now been reduced to little towns (Rasul et al. 2012). Floods and waterlogging have also put adverse impacts on the human health and their animals. Diarrhea, dysentery, and respiratory infections are frequent in the area, as are climate-sensitive diseases including malaria and dengue fever (Rahman et al. 2017). Climate change affects human-environmental interactions, socio-ecology frameworks, and their activities (Jongman et al. 2014), which enable the production of food, fibre, and energy at various levels (Neil Adger et al. 2005). Climate stress, and a lack of ability to adapt and modify it are all indicators of the coastal socio-ecological system's vulnerability (Rahman & Miah 2013). Climate change, lack of resources, and a limited adaptation ability in the deltaic community, are worsening the vulnerabilities and posing challenges to long-term food production in the deltaic region of Sindh, Pakistan Rasul et al. (2012). As a result, the local communities in the Indus delta are shifting from their ancestral homes to safer locations in search of food and shelter (Mahar 2010; Alamgir et al. 2015; Solangi 2019).

A socioeconomic survey collects quantitative data on a region's social, economic, and demographic factors. Seawater intrusion, worsened by climate change is posing a growing threat to the socio-economic conditions of Pakistan's coastal areas (Rahman et al. 2017). In light of these facts, the current study was carried out to assess the social and ecological climate change vulnerability in the Indus delta, Sindh, Pakistan.

To assess the social and ecological climate change vulnerability in the Indus delta, Sindh, Pakistan, a comprehensive Participatory Appraisal Survey was conducted through a well-structured questionnaire.

Using the above calculation, it was determined that the sample size should not be less than 384, hence 500 respondents were randomly selected from the entire deltaic area for the present study.

The study was conducted in all of the delta's union councils (local administrative divisions). As a result, it accurately represents the delta as a whole. The survey took into account the following factors:

• a.

  Current and previous occupations, current and previous sources of income;

• b.

  Socioeconomic analysis of changes in farm income (past and present), living habits, and any unusual diseases (not before encountered), etc.

• c.

  Any unusual or adverse environmental conditions in comparison to previous circumstances,

• d.

  Any perceived climatic changes by the community,

• e.

  Any perceived understanding by the residents about climate change and seawater intrusion and its effects on their sources of income

The collected data was statistically analyzed using the Pearson chi-square and Goodman and Kruskal's analyses. The IBM SPSS 22 software package was used to analyze the data.

The overall sample size is n, the number of poor people is q, the poverty line is z, and the lowest income is y_i. The headcount index calculates the percentage of the population who is poor, but it does not show how poor they are (Imran et al. 2013). The poverty-severity index, on the other hand, averages the squares of poverty gaps concerning the poverty line.

After the collection of the required primary field data, it was arranged in tables using descriptive statistics as discussed under.

Mulyanto & Magsi (2014) reported that for interpreting the social structure of a society, education is also an important indicator. According to this study, the literacy rate in the study area was around 49.60%, with 8.73% having a graduate degree, the highest qualification in the area. Furthermore, the majority of the people lived in Katcha houses built of wood, whereas only 21.43% of the inhabitants lived in pucca cemented houses, according to the survey. A single room housed an average of 4.7 family members. The findings regarding socioeconomic charactersistics of the present study are comparable to those reported by Magsi & Sheikh (2017) in their investigation of the socio-economic conditions of individuals in Badin District, Sindh, Pakistan.

However, 55.16% of the population keeps animals, 42.86% keeps animals for milk, and the rest, 57.14%, rely on animals for their livelihood. According to the survey reports, 89.28% of the population cooks with wood, while only 10.72% utilizes gas connections and portable gas cylinders. The majority of them collect wood for themselves, although 3.87% spend Rs. 500–2,000 each month for wood for cooking. Table 1 shows that 44.45% of respondents do not have access to power/electricity. In addition, the majority of respondents said their income is insufficient to maintain their family. As a result, they frequently borrow money from numerous sources on varying terms and conditions to maintain their families.

This section consists of describing climate change impacts, such as variations in rainfall patterns, temperature, wind storms, etc. as perceived by the community of the delta during the past 20 years.

This section describes the effects of seawater intrusion on the Indus delta's water resources, vegetation, crop cover, yield, soil salinity, fishing, and mangrove cover over the past 20 years.

Groundwater is the primary source of drinking water in the research area (Solangi 2019). According to this study, 75.40% of the Delta population uses groundwater extracted through hand pumps and shallow boreholes. While 13.89% of people use surfacewater, 3.17% use water from various water delivery schemes, and 7.54%t use water from tankers. As potable water was once available near their communities at shallow depths, according to the majority of respondents. However, they now have to obtain drinking water 5–10 kilometres away from their villages, which is both time consuming and economically infeasible (Rahman et al. 2017). Due to the requirement to collect water and perform all home responsibilities, time management for women in the family becomes tough (Rahman et al. 2017). Furthermore, 40.1% of respondents indicated that groundwater has turned brackish due to seawater intrusion into aquifers, and 78.97% said that the taste of groundwater is getting worse with each passing day.

Khanom (2016) reported that due to climate change and seawater intrusion, salinity intrusion in groundwater and natural wetlands has been steadily growing. The survey revealed that 20.4% of the people suffered from gastrointestinal disease, diarrhea, and chest and stomach problems. 14.8% were affected by skin diseases, 16.4% by hepatitis, 9.2% by cancer and 8.4% by cholera, diabetes, high blood pressure, heart, and kidney problems. Due to the use of contaminated water, insufficient quantity and quality of food, and a lack of healthcare services, the majority of the respondents reported that they are suffering from various diseases. Drinking of contaminated water can cause various diseases, such as: like diarrhea, indigestion, fever and other intestinal diseases (Solangi 2019). Salinity has a direct effect on stroke, left ventricular mass, stomach cancer, and many other disorders (He & MacGregor 2008). Common human ailments such as gastrointestinal distress, vomiting, diarrhoea, skin, and kidney problems, could be linked to low quality drinking water utilised by locals (Memon et al. 2011).

According to 96.03% of respondents, the inflow of highly saline water from the Arabian Sea into the delta has a negative influence on water supplies, agricultural fields, and crop yields, and eventually decreases the community's livelihood. The majority of participants said that these losses have become worse over the last 5–30 years. As a result, a number of families (about 15% of those surveyed) have relocated from their ancestral settlements to safer areas nearby cities/towns in search of food and shelter. Mahar (2010) reported that due to seawater intrusion, people are evacuating the traditional populated areas. Additionally, per acreage crop yield of agricultural lands is decreasing continuously, and the socio-economic conditions of the people are badly affected.

When asked about the main causes of seawater intrusion, 47.33% said it was due to a decrease in freshwater flow from the Indus River, while 4.11% said it was due to increasing sea levels. However, 25.51% said there was no flood protection along the Delta's shorelines. Deforestation of mangrove trees, building of the Left Bank Outfall Drain (LBOD), excavation of a tidal link canal, and destruction of Samandi Bandar were named as the main causes of coastal degradation by 18.1% of respondents.

Moreover, 94.84% of respondents (Table 2) reported that seawater has adversely affected their income. While asking about any change in cropping pattern during the past 20 years, 99.9% of the respondents reported no change in the cropping pattern. About 89.29% of the respondents reported there were not any mangrove forests in their area. However, 96.82% of the respondents said salinity in the delta has increased, and their agricultural practices are facing difficulties, due to higher levels of salinity, since increased salinity has an adverse impact on agricultural activities (Rahman et al. 2017).

The effects of seawater intrusion on several ecological climatic parameters were statistically investigated using Pearson Chi-square and Goodman and Kruskal's methods. Table 3 shows the results of the association between temperature fluctuations and a decrease in fish catch.

According to the data, 92.4% of respondents agreed that the temperature has changed. However, 83.2% of respondents said their fish catch had decreased. While 9.2% indicated no change or a decline in fish catch as a result of temperature changes in the delta. The Pearson chi-square analysis value for the link between change in temperature and decrease in fish catchment in the study region at the significant level of 0.58 was computed as 9.134, indicating that the two variables had a statistically weak relationship. The gamma (⁠ = 1.91) value of Goodman and Kruskal, with a significant level of 0.58, also indicates that this link was weak. Imran et al. (2013) reported similar findings in the Indus River Belt, demonstrating a link between temperature and fish catchment.

Table 4 shows the results of the association between increased seawater intrusion and decreased vegetation/agriculture.

According to Table 4, 96% of respondents agreed that seawater intrusion has increased. There had been a decrease in vegetation, according to 92.4% of respondents. However, 3.6% of respondents said there was no change in vegetation as a result of increased seawater intrusion. The Pearson chi-square analysis result for a link between these variables at a significant level of 0.03 was estimated as 14.205, indicating that these two variables have a strong relationship. This relationship was also substantial, as evidenced by the value of gamma (⁠ = 0.238). According to Hopkinson et al. (2008), the impact of sea-level rise and wind storms on forests has been severe in recent years.

Table 5 shows the results of the link between increased seawater intrusion and increased soil salinity.

According to the table, 94% of respondents indicated an increase in soil salinity. However, 2% of respondents said that increased seawater intrusion in the delta had no effect on soil salinity. The Pearson chi-square analysis value for the link between these variables at a significant threshold of 0.01 was estimated as 112.833, indicating that these two variables have a statistically significant relationship. The gamma value (0.672) also indicates that this relationship was fairly strong.

Table 6 shows the results of the association between changes in seawater intrusion and the negative influence on drinking water quality. According to the data, 93.6% of respondents experienced negative consequences. However, 2.4% of respondents said there were no negative effects on drinking water quality as a result of increased seawater intrusion. The Pearson chi-square analysis value for both variables was estimated as 70.604 at a significant level of 0.01, indicating that there is a statistically significant relationship between these two variables, while the value of gamma (0.531) also indicates that this relationship is quite strong.

Table 7 shows the results of the association between increased seawater intrusion and its negative effects on the community's income. According to the table, 94.8% of those surveyed had negative consequences. However, 1.2% of respondents said there was no negative impact on the community's income. The Pearson chi-squared test for a relationship between these two variables was calculated as 171.985 at a significant level of 0.01 indicating a very strong association between these two indicators, while the value of gamma (0.829) was also significant (p = 0.01) indicating a very strong association between these two indicators.

The degree of poverty was determined using Foster-Greer-Thorbeck techniques, which are the most reliable and extensively used techniques for estimating poverty lines. An international poverty level of 2 dollars (Imran et al. 2013; Solangi 2019) was chosen as a baseline, based on the current exchange rate.

Respondents were divided into four categories based on the international poverty level of $2: very poor, moderately poor, poor, and non-poor (IFAD 2002; Imran et al. 2013). The first class (very poor) was defined as being one-third of the poverty line, the second class (moderate poor) as being between one-third and two-thirds of the poverty line, the third class (poor) as being between two-thirds of the poverty line, and the fourth class as not being poor (Imran et al. 2013).

The findings revealed that poverty is quite severe in the coastal belt of Sindh, Pakistan. Based on the village survey (2004–05) as reported by Majeed et al. (2010), Thatta and Badin districts of southern Sindh Province of Pakistan were classified as districts below the poverty line. Furthermore, ADB (2005) and Majeed et al. (2010) reported that about 79% of the coastal population falls below the poverty line, out of which 54% are in the category of very poor. Similar poverty trends in Pakistan have been reported by Saboor et al. (2006). Behind these poverty ratios, the main factors include, at a minimum, the absence of physical infrastructure, less resource possession, lack of market resource integration, poor health, education indicators, and lack of proper management policies for poverty reduction (Joshi 2008; Israr & Khan 2010; Imran et al. 2013). It could hamper the growth trend and could create social unrest if attention is not paid to these poor communities (Morrison et al. 2007) who reside in the Indus delta.

The present study revealed that residents of the Indus delta are enduring poor infrastructure, poor living standards, and limited social activities. Most of the people are uneducated. The average family consisted of 11 members, whereas an average of 4.7 people lived in a single room. Many families have migrated from their ancestral areas to search for places that had a better potential to earn a sufficient income. Analysis based on the FGT techniques, about 88.4% community of the delta, were living below the poverty line. The Pearson chi-square and Goodman, Kruskal's analyses identified seawater intrusion as the most significant parameter affecting soil fertility, water quality, flora, fauna, mangroves, and livelihood of the Indus Delta community.Most of the people strongly requested an increased freshwater flow in the Indus River to its delta. In light of the findings of this study, it is concluded that there is a dire need for improving the environmental conditions by increasing freshwater flow below the Kotri Barrage, the last barrage on the Indus River before it flows to the delta. Appropriate water treatment/desalinization plants must be installed, introducing bio-saline agriculture should be considered, the degraded agricultural lands should be reclaimed to improve the infrastructure and protect the environment along the coast of Sindh. The facts reported in this study should certainly prompt responsible policymakers to devise strategies for mitigation of these adverse impacts of seawater intrusion on the socioeconomic conditions of the community living in the Indus delta. This change is necessary to save the ecosystem, agricultural lands, water resources, mangrove forests, fishing revenue, as well as the livelihood of the people living. The study findings will provide accurate data to demonstrate the current disastrous state of the delta area and suggest ways to promote realistic measures to remediate the delta and improve the lives of the residents.

Ghulam Shabir Solangi: concept, design, analysis, writing – review and editing. Altaf Ali Siyal: concept, design, analysis, writing – review and editing. Zain-ul-Abdin Siyal: concept, design, analysis, writing – review and editing. Pirah Siyal: concept, design, analysis, writing – review and editing. Sallahuddin Panhwar: review and editing. Hareef Ahmed Keerio: review and editing. Nabi Bux Bhatti: review and editing.

The U.S.-Pakistan Center for Advanced Studies in Water (U.S.-PCAS-W), Mehran University of Engineering & Technology, Jamshoro, Pakistan is highly acknowledged for funding the project ‘Assessing the impact of Seawater Intrusion on Soil, Water, and Environment in the Indus Delta using GIS and Remote Sensing’. Authors are also grateful to Dr Rick Bereit, Professor, The University of Utah, United States of America (USA), for his constructive comments and suggestions regarding the improvement of the article.

All relevant data are included in the paper or its Supplementary Information.

The authors declare there is no conflict.