Demystifying the impacts of anthropogenic activities on physicochemical characteristics of soil in four wetlands of Kashmir Valley, India – Nature

Executive Summary

A comprehensive assessment of four major wetlands in Kashmir—Hokersar, Anchar, Manasbal, and Shallabugh—was conducted between 2019 and 2021 to evaluate the impact of anthropogenic pressures on soil health. This report frames the findings within the context of the United Nations Sustainable Development Goals (SDGs), particularly SDG 6 (Clean Water and Sanitation), SDG 14 (Life Below Water), and SDG 15 (Life on Land). The study reveals a significant degradation of soil physicochemical and microbial properties in wetlands exposed to urban expansion, waste disposal, and tourism. Disturbed sites exhibited increased bulk density, elevated heavy metal concentrations, and reduced nutrient availability, directly compromising progress towards targets for pollution reduction and ecosystem restoration. Conversely, the relatively undisturbed Shallabugh wetland displayed superior soil quality, serving as a critical benchmark for healthy ecosystem functioning. These findings underscore the urgent need for integrated wetland governance and conservation strategies to halt land degradation, protect biodiversity, and ensure the continued delivery of essential ecosystem services, thereby contributing to the achievement of the 2030 Agenda for Sustainable Development.

Introduction: Aligning Wetland Conservation with Sustainable Development Goals

The Critical Role of Wetlands in Achieving the SDGs

Wetlands are indispensable ecosystems that provide foundational support for numerous Sustainable Development Goals. Their functions are integral to environmental stability and human well-being. Key contributions include:

• SDG 6 (Clean Water and Sanitation): Wetlands act as natural filters, purifying water and recharging groundwater aquifers, which is essential for providing clean water resources.
• SDG 13 (Climate Action): These ecosystems are significant carbon sinks, sequestering atmospheric carbon and regulating local microclimates, thus playing a vital role in climate change mitigation and adaptation.
• SDG 14 (Life Below Water) & SDG 15 (Life on Land): As biodiversity hotspots, wetlands provide critical habitats for a vast array of aquatic and terrestrial species, including migratory birds. Their health is a direct indicator of progress towards halting biodiversity loss.
• SDG 2 (Zero Hunger) & SDG 8 (Decent Work and Economic Growth): Wetlands support local livelihoods through fisheries, agriculture, and the provision of natural resources, contributing to food security and economic stability.

Anthropogenic Threats to Kashmir’s Wetlands and SDG Targets

The wetlands of the Kashmir Valley are facing unprecedented threats from human activities, which directly impede the attainment of several SDG targets. These pressures include:

1. Urbanization and Encroachment: Unplanned urban expansion leads to the conversion of wetland areas, destroying habitats and impairing hydrological functions, undermining SDG 11 (Sustainable Cities and Communities) and SDG 15.
2. Pollution and Waste Disposal: The dumping of solid waste and runoff from agricultural fields introduce pollutants and heavy metals into wetland soils and water, threatening water quality (SDG 6) and ecosystem health (SDG 14, SDG 15).
3. Unsustainable Tourism and Grazing: Excessive tourism and grazing degrade vegetation cover, compact soil, and disrupt wildlife, leading to a decline in the ecological integrity required to meet biodiversity targets under SDG 15.

This degradation represents a significant setback for regional sustainability, transforming these vital ecological assets into liabilities and highlighting a critical gap in environmental governance.

Methodology: Assessing Environmental Impact in Line with SDG Monitoring

Study Area and Rationale

The study was conducted across four key wetlands in the Kashmir Valley, selected to represent a gradient of anthropogenic disturbance:

• Highly Disturbed Sites: Hokersar and Anchar wetlands, located in or near urban centers, are subject to intense pressure from pollution and encroachment.
• Less Disturbed Sites: Manasbal and Shallabugh wetlands, situated in more rural settings, experience comparatively lower levels of human interference. Shallabugh, in particular, serves as a relatively pristine reference site.

This comparative approach allows for a clear assessment of how different levels of human activity impact ecosystem health, providing data crucial for monitoring progress on SDG 15.1 (conserve and restore terrestrial and freshwater ecosystems) and SDG 6.6 (protect and restore water-related ecosystems).

Data Collection and Analysis

To quantify the impact of disturbances, a systematic analysis of soil properties was performed. The methodology included:

1. Soil Sampling: Samples were collected from the 0–30 cm soil layer at multiple sub-sites within each wetland to ensure representative data.
2. Physicochemical Analysis: A suite of parameters was measured, including pH, electrical conductivity (EC), bulk density, organic carbon, and available nutrients (N, P, K, Ca, Mg).
3. Heavy Metal Analysis: Concentrations of key heavy metals (Fe, Cu, Zn, Ni, Cd, Mn) were determined using atomic absorption spectrophotometry (AAS) to assess pollution levels in line with SDG 12.4 (environmentally sound management of chemicals and wastes).
4. Microbial Analysis: Total bacterial count and Vesicular Arbuscular Mycorrhiza (VAM) spore counts were quantified as bio-indicators of soil health and biodiversity (SDG 15.5).
5. Statistical Analysis: Two-way ANOVA and Principal Component Analysis (PCA) were employed to determine significant differences between sites and identify key drivers of soil degradation.

Results and Discussion: Soil Degradation as a Barrier to Sustainable Development

Physicochemical Indicators of Environmental Stress

The analysis revealed a clear distinction between disturbed and undisturbed wetlands. In disturbed sites like Hokersar and Anchar, soil quality was significantly compromised:

• Elevated pH and EC: Higher pH (6.92) and EC (0.31 dS m⁻¹) were recorded in disturbed wetlands, indicating altered soil chemistry due to pollution and reduced organic matter. This imbalance threatens the habitat suitability for native flora and fauna, hindering efforts under SDG 15.
• Increased Bulk Density: Disturbed sites showed higher bulk density (up to 0.66 g/cm³), a sign of soil compaction from grazing and human traffic. This reduces water infiltration and root growth, contributing to land degradation (SDG 15.3).
• Depleted Organic Carbon: The undisturbed Shallabugh wetland had significantly higher organic carbon (4.11%) and moisture content (47.60%) compared to disturbed sites. This highlights the critical role of intact vegetation in carbon sequestration (SDG 13) and maintaining soil fertility.

Nutrient Dynamics and Soil Fertility (SDG 2, SDG 15)

Nutrient cycling, a cornerstone of ecosystem productivity, was severely disrupted in disturbed wetlands. The findings show:

• Nitrogen and Potassium Depletion: Available nitrogen and potassium were significantly lower in polluted areas. This loss of essential nutrients reduces soil fertility, impacting both the natural ecosystem and adjacent agricultural lands, which relates to SDG 2 (Zero Hunger).
• Altered Phosphorus Availability: Phosphorus levels were higher in disturbed wetlands, likely due to runoff from agricultural fertilizers and domestic waste. This contributes to eutrophication, a major threat to aquatic ecosystems (SDG 14.1).

Heavy Metal Contamination and Pollution (SDG 3, SDG 6, SDG 12)

A critical finding was the accumulation of heavy metals in disturbed wetlands. Concentrations of Fe, Cu, Zn, Ni, Mn, and Cd were significantly higher in soils at Hokersar and Anchar. This contamination poses a direct threat to multiple SDGs:

• It degrades water quality, making it unsafe for human and ecological use (SDG 6.3).
• It introduces toxins into the food chain, posing risks to human health (SDG 3.9).
• It reflects irresponsible waste management practices, which contravenes the principles of SDG 12 (Responsible Consumption and Production).

Microbial Health as a Bio-indicator for SDG 15

Soil microbial communities are vital for nutrient cycling and overall ecosystem resilience. The study found:

• The highest bacterial count and VAM spore population were recorded in the undisturbed Shallabugh wetland.
• Disturbed sites showed significantly lower microbial populations, indicating that pollution and physical disturbance are creating a sterile soil environment.

This decline in microbial diversity is a key indicator of ecosystem degradation and a direct threat to the targets of SDG 15, which aim to halt biodiversity loss.

Multivariate Analysis: Distinguishing Degraded vs. Healthy Ecosystems

Principal Component Analysis (PCA) successfully differentiated the wetland sites based on their soil properties. The analysis confirmed that parameters associated with soil health (organic carbon, moisture, nutrients) were strongly correlated with the undisturbed Shallabugh site. In contrast, indicators of degradation (heavy metals, high pH, bulk density) were associated with the disturbed sites. This statistical validation reinforces the conclusion that anthropogenic activities are the primary drivers of wetland degradation in the region.

Conclusion: An Urgent Call for Integrated Management to Meet SDG Targets

The investigation confirms that anthropogenic pressures are causing severe degradation of soil health in Kashmir’s wetlands, thereby undermining regional progress towards the Sustainable Development Goals. The compromised soil quality, characterized by altered chemistry, nutrient depletion, heavy metal contamination, and loss of microbial life, directly threatens the ecosystem services essential for clean water (SDG 6), biodiversity (SDG 15), and climate regulation (SDG 13). The continued decline of these ecosystems will have long-term negative consequences for both environmental stability and local livelihoods.

Effective governance and integrated management are imperative to reverse these trends. Protecting these fragile ecosystems is not merely an environmental issue but a fundamental requirement for achieving sustainable development in the region.

Recommendations for Future Action

To address the challenges identified in this report and align conservation efforts with the 2030 Agenda, the following actions are recommended:

1. Implement Strict Land-Use Regulations: Enforce regulations to prevent further encroachment and land conversion in and around wetland areas, directly supporting SDG 11 and SDG 15.
2. Establish Pollution Control Measures: Develop and implement strategies for managing solid waste, agricultural runoff, and industrial effluents to reduce the pollution load on wetlands, contributing to SDG 6 and SDG 12.
3. Promote Sustainable Tourism: Introduce and enforce guidelines for sustainable tourism to minimize its ecological footprint on sensitive wetland ecosystems.
4. Launch Restoration and Monitoring Programs: Initiate long-term ecological monitoring and science-based restoration projects for degraded wetlands, using sites like Shallabugh as a reference for success. This is crucial for tracking progress on SDG 15.3 and SDG 6.6.
5. Engage Local Communities: Involve local stakeholders in conservation planning and management to ensure that strategies are socially equitable and economically viable, fostering a sense of ownership and shared responsibility.

Analysis of Sustainable Development Goals in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

• SDG 6: Clean Water and Sanitation: The article discusses the degradation of water quality in wetlands due to anthropogenic pressures like waste disposal. It highlights that wetlands are crucial for groundwater recharge and maintaining the water table, directly linking to the goal of ensuring the availability and sustainable management of water.
• SDG 11: Sustainable Cities and Communities: The article explicitly identifies “urban expansion” and “dumping of solid wastes” as major threats to the wetlands. This connects to the goal of making cities inclusive, safe, resilient, and sustainable by addressing the environmental impact of urban areas, particularly on surrounding ecosystems.
• SDG 12: Responsible Consumption and Production: The issues of “waste disposal,” “dumping of solid wastes,” and the “widespread use of pesticides and fertilizers” mentioned in the article are directly related to unsustainable production and consumption patterns. This aligns with SDG 12’s aim to ensure the environmentally sound management of chemicals and wastes.
• SDG 14: Life Below Water: While primarily focused on marine ecosystems, the principles of SDG 14 apply to the inland aquatic ecosystems discussed. The article details the pollution and degradation of wetlands and lakes (Hokersar, Anchar, Manasbal, Shallabugh), which are vital freshwater bodies, connecting to the goal of conserving and sustainably using aquatic resources.
• SDG 15: Life on Land: This is the most central SDG to the article. The study focuses on the degradation of wetland ecosystems, loss of soil health, decline in microbial diversity, and threats to biodiversity hotspots. It directly addresses the need to protect, restore, and promote the sustainable use of terrestrial and inland freshwater ecosystems and halt land degradation and biodiversity loss.

2. What specific targets under those SDGs can be identified based on the article’s content?

1. SDG 6: Clean Water and Sanitation

   • Target 6.3: By 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials. The article’s focus on pollution from waste disposal and agricultural runoff degrading water quality in the wetlands directly relates to this target.
   • Target 6.6: By 2020, protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers, aquifers and lakes. The entire study is an assessment of wetland degradation and emphasizes the need for “effective wetland governance and conservation strategies,” which is the core of this target. The article notes the shrinkage of Hokersar wetland as an example of ecosystem loss.

2. SDG 11: Sustainable Cities and Communities

   • Target 11.6: By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management. The article identifies “urban expansion” and “dumping of solid wastes” from urban/peri-urban systems like Hokersar and Anchar as key pressures, linking directly to this target.

3. SDG 12: Responsible Consumption and Production

   • Target 12.4: By 2020, achieve the environmentally sound management of chemicals and all wastes throughout their life cycle… and significantly reduce their release to air, water and soil to minimize their adverse impacts on human health and the environment. The mention of heavy metal contamination (Fe, Cu, Zn, Ni, Cd, Mn) and pollution from pesticides and fertilizers aligns with the need for better chemical and waste management.

4. SDG 14: Life Below Water

   • Target 14.1: By 2025, prevent and significantly reduce marine pollution of all kinds, in particular from land-based activities, including marine debris and nutrient pollution. Although this target specifies “marine” pollution, the principles are directly applicable to the land-based pollution (waste, agricultural runoff) affecting the inland wetland ecosystems discussed in the article.

5. SDG 15: Life on Land

   • Target 15.1: By 2020, ensure the conservation, restoration and sustainable use of terrestrial and inland freshwater ecosystems and their services, in particular forests, wetlands, mountains and drylands. The article’s core theme is the assessment of wetland degradation and the call for conservation, making this target highly relevant.
   • Target 15.3: By 2030, combat desertification, restore degraded land and soil, including land affected by desertification, drought and floods, and strive to achieve a land degradation-neutral world. The study’s detailed analysis of soil degradation—including changes in bulk density, loss of organic carbon, and heavy metal contamination—directly addresses the restoration of degraded soil.
   • Target 15.5: Take urgent and significant action to reduce the degradation of natural habitats, halt the loss of biodiversity and, by 2020, protect and prevent the extinction of threatened species. The article describes the wetlands as “vital biodiversity hotspots” and habitats for migratory birds, and its findings on degradation highlight the urgency of this target.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

• Soil Physico-chemical Properties: The article provides quantitative data on several soil parameters that serve as direct indicators of soil health and degradation (relevant to Target 15.3). These include:
  • Soil pH
  • Electrical Conductivity (EC, dS m⁻¹)
  • Bulk Density (g cm⁻³)
  • Soil Organic Carbon (%)
  • Available Nitrogen (mg kg⁻¹)
  • Available Phosphorus (mg kg⁻¹)
  • Available Potassium (mg kg⁻¹)
• Heavy Metal Contamination: The measurement of heavy metals (Fe, Cu, Zn, Ni, Cd, Mn) in mg/kg serves as a direct indicator of pollution from land-based activities (relevant to Targets 6.3 and 12.4). The article shows elevated levels in disturbed wetlands.
• Microbial Indicators: The study measures soil microbial health, which is a key indicator of ecosystem functionality (relevant to Target 15.1). The specific indicators used are:
  • Total bacterial count (CFU g⁻¹ of soil)
  • Vesicular Arbuscular Mycorrhiza (VAM) spore count (spores per gram of soil)
• Extent of Water-Related Ecosystems: The article implies this indicator by stating that the Hokersar wetland “which once covered 18.75 km² in 1969, had shrunk to 13 km² by 2008.” This change in area is a direct measure for Target 6.6.
• Vegetation Cover: The article mentions that a “decline in vegetation cover” is a consequence of biotic and abiotic pressures. While not quantified with a specific metric, it is an implied indicator of ecosystem degradation (relevant to Target 15.1).

4. Summary Table of SDGs, Targets, and Indicators

Source: nature.com