Operationalizing Nature-Based Solutions for Urban Sustainability in Hyper-Arid Regions: The Case of the Eastern Province, Saudi Arabia

Abstract

As global urbanization accelerates in ecologically fragile regions, Nature-Based Solutions (NBS) have emerged as a critical paradigm for integrating environmental sustainability with urban resilience. Particularly in hyper-arid environments, the deployment of NBS must navigate unique climatic, hydrological, and socio-political complexities. This paper advances a conceptual framework that synthesizes the International Union for Conservation of Nature’s (IUCN) tripartite typology—protection, sustainable management, and restoration/creation—within a broader systems-oriented governance lens. By engaging with international precedents and context-specific urban dynamics, the study explores how adaptive, multiscale strategies can translate ecological principles into actionable urban design and planning practices. Through a comparative lens and grounded regional inquiry, the research identifies critical leverage points and institutional enablers necessary to operationalize NBS under desert constraints. While highlighting both the structural potential and the contextual limitations of existing initiatives in the Eastern Province of Saudi Arabia, the analysis underscores the necessity of coupling typological coherence with flexible regulatory and participatory mechanisms. Empirical findings from the Saudi case reveal persistent institutional fragmentation, heavy reliance on top-down implementation, and limited hydrological monitoring as key constraints, while also pointing to emerging governance mechanisms under Vision 2030—such as cross-sectoral coordination and pilot participatory frameworks—that can support the long-term viability of NBS in hyper-arid cities. Building on these insights, the study distills a set of strategic lessons that provide clear guidance on hydrological integration, adaptive governance, and socio-cultural legitimacy, offering a practical roadmap for operationalizing NBS in desert urban contexts.

1. Introduction

Nature-Based Solutions (NBS) offer a globally recognized framework for addressing climate, biodiversity, and urban sustainability challenges in an integrated way. Defined by the International Union for Conservation of Nature (IUCN) as “actions to protect, sustainably manage, and restore natural or modified ecosystems that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits” [1], NBS encompass a broad spectrum of interventions that merge ecological restoration with socio-economic objectives. They are increasingly adopted in global policy agendas, including the European Green Deal, the UN Decade on Ecosystem Restoration, and the Paris Climate Agreement targets [2,3,4]. Evidence from diverse geographies shows that NBS can deliver multiple co-benefits, such as enhanced biodiversity, reduced disaster risk, improved public health, and strengthened climate resilience [5,6,7,8]. Global analyses estimate that these solutions could contribute up to 37% of the cost-effective climate mitigation required by 2030 to maintain global warming below 2 °C [9].

Applying NBS in desert and hyper-arid environments presents distinct ecological and socio-economic challenges. These environments cover over 40% of the Earth’s terrestrial surface, with annual rainfall often below 250 mm, high evapotranspiration rates, and limited soil organic matter [10,11,12]. Fragile ecosystems in these regions are highly vulnerable to erosion, salinization, and biodiversity loss. Climatic extremes are often compounded by rapid urbanization, competing land uses, and governance constraints such as fragmented institutional responsibilities, insufficient funding, and limited technical capacity [13,14,15,16]. Despite these constraints, desert regions also present opportunities for deploying hybrid ecological–engineering interventions that can create microclimatic cooling, support water-sensitive urban design, and restore degraded habitats in ways that align with cultural and economic priorities [17,18,19].

Saudi Arabia’s Vision 2030 positions environmental stewardship and sustainability as national development priorities. Flagship initiatives such as the Saudi Green Initiative (SGI) and the Middle East Green Initiative aim to plant 10 billion trees, rehabilitate 40 million hectares of degraded land, and expand the network of protected areas [20,21]. The Eastern Province, with its unique coastal–desert interface, is an area of high ecological and economic significance, hosting mangrove forests, sabkhas, and saline wetlands alongside major urban and industrial centers. However, it faces critical challenges including rising urban heat island effects, declining biodiversity, water scarcity, and degradation of sensitive coastal ecosystems [22,23]. Current interventions—such as mangrove conservation projects, wetland rehabilitation, and the creation of green public spaces—demonstrate emerging applications of NBS, but these remain fragmented and insufficiently integrated into a comprehensive, region-specific framework.

Operationalizing the IUCN tripartite typology in hyper-arid urban contexts remains an underexplored area of research. The typology—comprising protection, sustainable management, and restoration/creation—offers conceptual clarity for classifying NBS interventions but requires adaptation to the specific ecological, hydrological, and governance realities of Gulf-region cities [1]. Existing research rarely combines typological classification with systems-based governance analysis to evaluate both ecological outcomes and institutional arrangements in such contexts. This gap limits the ability of policymakers and practitioners to design, implement, and monitor NBS that are both ecologically viable and socially supported in hyper-arid urban environments. Accordingly, beyond analyzing international and regional case studies, this research also develops a set of strategic lessons aimed at guiding the design, governance, and implementation of NBS in Gulf-region cities.

This study addresses this gap by integrating the IUCN tripartite typology with a systems-based governance framework to assess the potential of NBS in the Eastern Province of Saudi Arabia. It does so by analyzing three international dryland case studies—the Loess Plateau Rehabilitation Project (China), the Mojave Stewardship Initiative (USA), and the Ash Meadows National Wildlife Refuge (USA)—to extract transferable ecological and governance principles. These insights are then evaluated in relation to the environmental, socio-economic, and policy context of the Eastern Province. This study is guided by three research questions:

• How can the IUCN tripartite typology be adapted to address the socio-ecological conditions of hyper-arid urban environments?
• What design and governance lessons from international dryland NBS can inform implementation in Gulf-region cities?
• What opportunities and constraints shape the deployment of NBS in the Eastern Province under Vision 2030?

2. Methods

This study employs a comparative case study approach to evaluate Nature-Based Solutions in hyper-arid contexts through the integration of the IUCN tripartite typology with a systems-based governance framework. The research design was developed to address both ecological and institutional dimensions of NBS, recognizing that technical success in arid regions requires governance arrangements capable of adaptive management. The IUCN typology categorizes NBS into three main types—protection, sustainable management, and restoration/creation—which serve as a baseline for classifying interventions [1]. To address the complexity of hyper-arid urban systems, this typology was embedded in a systems-based framework that considers ecological processes, hydrological dynamics, socio-economic drivers, and institutional structures.

Case study selection was guided by ecological relevance, diversity of governance models, and transferability of lessons to Gulf-region contexts. Three international dryland cases were chosen:

• Loess Plateau Rehabilitation Project (China)—a large-scale semi-arid landscape restoration integrating agroforestry, soil erosion control, and community-based land management.
• Mojave Stewardship Initiative (USA)—a hyper-arid conservation program combining native plant restoration, adaptive governance, and seed zone mapping.
• Ash Meadows National Wildlife Refuge (USA)—a hydrologically dependent desert oasis restoration focused on endemic species recovery and invasive species control.

These cases represent a spectrum of environmental conditions and management approaches, providing an empirical basis for identifying generalizable principles applicable to the Eastern Province of Saudi Arabia.

Multiple data sources were used to ensure a robust and triangulated analysis of each case. Primary and secondary data included peer-reviewed scientific literature, project monitoring reports, governmental and non-governmental policy documents, hydrological and ecological datasets, and spatial imagery. Quantitative indicators—such as changes in vegetation cover, soil carbon content, evapotranspiration rates, and biodiversity indices—were extracted where available to enable cross-case comparisons. Spatial data analysis was used to validate reported land cover changes and to contextualize ecological outcomes.

The analytical procedure was conducted in four sequential stages to ensure methodological consistency across cases.

• Case profiling—Documenting baseline conditions, implemented interventions, and observed ecological and socio-economic outcomes.
• Typology mapping—Classifying interventions within each case according to the IUCN framework (protection, sustainable management, restoration/creation).
• Systems integration assessment—Evaluating how ecological, hydrological, social, and governance components were integrated into project design and management.
• Contextual application—Comparing the derived principles with the environmental, policy, and socio-economic conditions of the Eastern Province to assess transferability and identify potential barriers to implementation.

A schematic diagram was developed to visualize the research process and the integration of the applied frameworks. Figure 1 presents the methodological sequence, starting from the systems-based framework that integrates ecological, social, and governance dimensions, and linking it to the IUCN’s tripartite typology of protection, sustainable management, and restoration/creation. This combined framework guided two main analytical stages: a comparative review of three international dryland case studies—the Loess Plateau in China, the Mojave Stewardship Initiative in California, and the Ash Meadows National Wildlife Refuge in Nevada—and its empirical application in assessing NBS initiatives in the Eastern Province of Saudi Arabia. The diagram highlights how the theoretical underpinnings are connected to both comparative analysis and local evaluation, ensuring that ecological outcomes and governance structures are examined in a consistent and systematic manner, and providing a solid basis for generating context-specific recommendations for hyper-arid urban environments.

3. Results

The following section presents the outcomes of the comparative analysis, detailing ecological interventions, governance approaches, and implementation challenges across the three international dryland case studies and the Eastern Province of Saudi Arabia.

3.1. The Loess Plateau Rehabilitation Project in China

The Loess Plateau rehabilitation project in China (Figure 2), (

Table 1. Quantitative landscape profile of the Loess Plateau Rehabilitation Project in China.

Category	Indicator
Geographic and Climatic Scope
Location	Loess Plateau, North-Central China
Total area	~640,000 km2
Rehabilitation zone	~35,000 km2
Elevation	800–1500 m above sea level
Annual precipitation	200–600 mm
Evapotranspiration	2–5 times higher than precipitation
Degradation Baseline (Pre-Intervention)
Soil erosion	Up to 10,000 tons/km2/year
Vegetation cover	<30% in many watersheds
Sediment yield (to Yellow River)	>300 million tons/year
Soil organic matter	Often below 2%
Interventions
Terracing	~2.5 million hectares
Afforestation area	~35,000 km2
Grain-for-Green program	>15 million hectares converted to forest/grassland
Sustainable practices	Rotational grazing, agroforestry, contour farming
Ecological Outcomes
Increase in soil organic carbon	Up to 60% in upper soil layers
Vegetation cover post-rehab	Increased to ~60%
Reduction in sediment yield	~100 million tons/year
Reduction in surface runoff	35–70% (site-dependent)
Socio-Economic Metrics
Household income	Increased by 50–100% in pilot counties
Number of farmers engaged	>2.5 million
Program cost	~$4.5 billion USD (1999–2009)
Challenges and Trade-offs
Groundwater depletion	Significant drying in deeper soil layers after 6–10 years
Monoculture vulnerability	Susceptibility to drought and pests
Decline in base flows	30–50% in some catchments
Monitoring and Governance
Monitoring tools	Annual remote sensing and field surveys
Ecological modeling	Sediment retention, carbon stocks, hydrology
Governance model	Initially centralized, increasingly decentralized post-2005

) stands as a scientifically rigorous and policy-enabled exemplar of Nature-Based Solutions (NBS) in dryland environments, offering valuable insights for desert settlements such as Al Khobar, KSA. Although classified as semi-arid, the plateau shares key ecological challenges with arid zones—including extreme land degradation, high evapotranspiration, and sparse vegetation cover—enhancing its translational potential across similar contexts [12,24]. Guided by the IUCN’s tripartite NBS framework, the region’s rehabilitation integrated protection (preserving remnant native vegetation and stabilizing watershed buffers), sustainable management (contour terracing, rotational grazing, and agroforestry under the Grain-for-Green program), and large-scale restoration and creation (afforesting over 35,000 km² and installing sediment retention systems). These combined efforts yielded measurable results: a 60% increase in soil organic carbon and a 100 million tons annual reduction in sediment loads to the Yellow River [25,26,27]. Its durability is further reinforced by long-term policy continuity, socio-economic mechanisms for farmer engagement, and scientific monitoring protocols—key prerequisites for replicable NBS in resource-limited desert sectors. While recognizing climatic differences—particularly the plateau’s higher rainfall (300–600 mm/year)—the application of native species, traditional land uses, and adaptive water harvesting fosters strategies directly relevant to arid urban landscapes. Moreover, lessons from earlier missteps—such as overreliance on non-native monocultures that exacerbated groundwater depletion—emphasize the value of ecological specificity and adaptive resilience in NBS design [28].

Despite these successes, the Grain-for-Green Program also illustrates critical nuances in scaling NBS across semi-arid and hyper-arid landscapes. By converting approximately 15 million hectares of steep farmland to forest and grassland, the initiative achieved a ~25% increase in vegetation cover, reduced erosion, elevated carbon storage, and bolstered habitat functions [26,32]. However, the extensive use of deep-rooted, water-demanding monocultures—most notably Robinia pseudoacacia—resulted in desiccation of deeper soil profiles and reduced downstream flows in the Yellow River basin [28,33,34]. Meta-analyses confirm that surface soil moisture initially improved but declined significantly in deeper horizons after 6–10 years of afforestation [28,33]. Moreover, the limited genetic diversity of single-species stands reduced biodiversity and ecological resilience, prompting a transition toward mixed-species native plantings [35,36]. This duality underscores a critical message: while large-scale NBS can restore ecosystem services effectively, they may also provoke unintended hydrological stress and biodiversity loss if ecological parameters—such as species selection and water dynamics—are neglected. For desert settlements like Al Khobar, these outcomes underscore the need for systems-based, adaptive NBS approaches that rigorously assess ecological compatibility, water-use efficiency, and long-term multifunctional benefits in arid landscapes.

3.2. The Mojave Stewardship Initiative in California

The Mojave Stewardship initiative in California (Figure 3), (

Table 2. Quantitative landscape profile of the Mojave Stewardship initiative in California.

Category	Indicator
Geographic and Climatic Scope
Location	Mojave Desert, California, USA
Area covered	>60,000 hectares under formal conservation and stewardship
Elevation	Ranges from 600 to 2400 m above sea level
Annual precipitation	<150 mm
Temperature range	–7 °C (winter) to 45 °C (summer); high diurnal and seasonal variability
Ecological Context and Baseline
Ecosystem type	Hyper-arid desert with endemic flora and fauna
Key species	Larrea tridentata (creosote bush), Stipa hymenoides, Joshua trees
Primary stressors	Drought, invasive species, urban expansion, habitat fragmentation
Protection Interventions
Protected area designation	>60,000 hectares under California Desert Protection Act and land trusts
Legal status	Federal and state protected areas, tribal lands, conservation easements
Sustainable Management
Native plant program	Mojave Desert Native Plant Program (MDNPP)
Seed transfer zones	Ecotypic zones developed using empirical trials
Community nurseries	Operated to propagate drought-resilient, locally adapted species
Species used	Larrea tridentata, Ambrosia dumosa, Atriplex spp., native grasses
Restoration and Creation
Urban green infrastructure	Bioswales, pollinator gardens, wildlife corridors in cities like Las Vegas
Projects under Urban Wildlife Conservation Program	Several city-scale restoration efforts across Nevada-California border
Governance and Monitoring
Governance model	Polycentric: USFWS, BLM, NGOs, tribal entities
Tools used	Mojave Seed Menus decision-support app
Indigenous involvement	Tribal ecological knowledge integrated into planning and monitoring
Monitoring systems	Climate-resilient plant survival rates, adaptive revegetation success
Challenges and Trade-offs
Seed supply constraints	Limited seed availability for restoration during extended drought
Wildlife predation	Threatens survival of new plantings
Hydrological uncertainty	Variable rainfall limits restoration consistency
Social and Institutional Outcomes
Stakeholder engagement	High, including tribal, federal, state, and local entities
Institutional adaptability	Use of empirical trials and participatory governance to guide restoration

) demonstrates a scientifically robust and contextually appropriate application of Nature-Based Solutions (NBS) in hyper-arid environments, aligning closely with IUCN’s tripartite framework: protection, sustainable management, and restoration/creation. Located in the Mojave Desert—an ecosystem defined by extreme temperature fluctuations, annual precipitation under 150 mm, and a suite of sensitive endemic species—this program offers critical parallels to Gulf desert cities such as Al Khobar [37,38]. As a protection measure, it has secured over 60,000 ha of intact desert habitat through legal designations (e.g., California Desert Protection Act) and strategic land trusts, preserving keystone ecosystems including Joshua tree woodlands and desert tortoise habitats [38]. The sustainable management dimension is robustly represented by the Mojave Desert Native Plant Program (MDNPP), which combines ecotypic seed zone mapping, community-operated nurseries, and adaptive revegetation protocols to deploy genetically appropriate, drought-resilient species—such as Larrea tridentata and Stipa hymenoides—thereby enhancing ecological fit and water use efficiency [38]. In urban and peri-urban zones, the initiative has implemented restoration and creation interventions—such as pollinator gardens, bioswales, and wildlife corridors—under the Urban Wildlife Conservation Program, effectively re-establishing habitat connectivity and ecological functionality in cities like Las Vegas.

Transitioning beyond conventional NBS design, the Mojave initiative exemplifies a flexible, systems-based model that integrates ecological precision with multi-stakeholder governance and social adaptability. The MDNPP’s empirically grounded seed transfer zones, based on common-garden trials, ensure climate-appropriate plant selection and reduce maladaptation risks [42]. Governance is organized through a polycentric partnership involving USFWS, USGS, BLM, tribal entities, and NGOs—enhancing resilience through distributed authority and local accountability. Nonetheless, challenges in maintaining seed supply during extended drought and wildlife predation underscore the limits of technical solutions absent social and institutional support [43]. In response, the initiative introduced tools like the Mojave Seed Menus decision-support app and embedded indigenous ecological knowledge via tribal collaborations, signaling a shift toward inclusive governance models [38,44]. These adaptive mechanisms mirror academic recommendations for iterative, socio-ecologically integrated frameworks [45,46]. Consequently, the Mojave Stewardship not only delivers measurable ecosystem restoration but also models an operationally resilient, governance-driven blueprint—crucial for designing NBS in arid urban regions like Al Khobar.

3.3. The Ash Meadows National Wildlife Refuge in Nevada

The Ash Meadows National Wildlife Refuge in Nevada (Figure 4), (

Table 3. Quantitative landscape profile of the Ash Meadows National Wildlife Refuge in Nevada.

Category	Indicator
Geographic and Climatic Scope
Location	Amargosa Valley, Nye County, Nevada, USA
Area	~23,000 acres (~9300 hectares)
Climate type	Hyper-arid; desert oasis ecosystem
Annual precipitation	<130 mm
Primary hydrological feature	Fossil aquifer-fed springs (terminal discharge system)
Ecological Context and Baseline
Unique features	One of the largest remaining desert spring ecosystems in the U.S.
Endemic species	26 species, including Cyprinodon nevadensis mionectes (Ash Meadows pupfish)
Baseline threats	Groundwater extraction, invasive species, habitat fragmentation
Ramsar designation	Wetland of International Importance
Protection Interventions
Legal protection	Federal refuge status since 1984; expanded under Ramsar and NEPA guidelines
Land acquisition	Key lands acquired to prevent development and protect aquifer integrity
Development halts	BLM halted lithium exploration near the refuge in 2023 to protect aquifer
Sustainable Management
Invasive species control	Green sunfish removal, tamarisk eradication
Infrastructure removal	Legacy agricultural ditches and impoundments dismantled
Hydrological restoration	Spring flows reconnected and enhanced to mimic natural regimes
Endangered species recovery	Pupfish population recovered in restored habitats
Restoration and Creation
Channel reconfiguration	Crystal and Kings Springs re-engineered for ecological flow restoration
Wash reconnection	Improved hydrological connectivity and sediment transport
Habitat creation	Wetlands, shallow channels, and shaded aquatic refugia
Governance and Monitoring
Governance structure	Polycentric: USFWS, tribal governments, NGOs, federal and academic partners
Monitoring programs	Participatory and scientific; includes hydrology, biota, and spring dynamics
Adaptive management	Iterative approach with stakeholder feedback loops and ecological assessments
Challenges and Trade-offs
Water table stress	Continued vulnerability from regional groundwater pumping
Long-term funding	Maintenance dependent on limited and competitive federal resources
Invasive species recurrence	Requires continual surveillance and rapid response capacity
Social and Institutional Outcomes
Tribal collaboration	Inclusion of indigenous knowledge and management practices
Educational programs	Community outreach and ecological education for visitors and residents
Policy integration	Coordination with regional water planning and biodiversity strategies

) represents one of the most scientifically rigorous and operationally integrated applications of Nature-Based Solutions (NBS) in hyper-arid desert landscapes, embodying the IUCN tripartite framework of protection, sustainable management, and restoration/creation. As a protection intervention, the 23,000-acre refuge secures a globally rare fossil-aquifer–fed oasis, designated a Ramsar Wetland of International Importance, thus preserving hydrological integrity and habitat for 26 endemic species while safeguarding against threats from upstream groundwater extraction such as nearby lithium mining [38,45,47]. In the realm of sustainable management, refuge biologists have successfully eliminated invasive taxa—including green sunfish—while dismantling legacy agricultural infrastructure. These efforts have restored spring flow dynamics and resulted in the resurgence of the Ash Meadows Amargosa pupfish from near absence to predominance in restored spring ecosystems [38,42]. Under restoration/creation, hydrological engineering at Crystal and Kings Springs—through impoundment removal, wash reconnection, and channel reconfiguration—has reinstated structural complexity and enabled early recovery of endangered pupfish and endemic invertebrates [38,42]. Despite persistent challenges—such as continued aquifer stresses, invasive species surveillance requirements, and reliance on constrained funding for long-term maintenance [38,42,48]. Ash Meadows exemplifies how integrated policy, hydrological science, and coordinated multi-stakeholder engagement can effectively restore and maintain vital desert ecosystem services, presenting a model for multifunctional NBS in desert urban regions like Al Khobar.

To scale the efficacy of such NBS interventions to rapidly urbanizing desert contexts, scholars emphasize that flexible, systems-based frameworks—characterized by iterative learning, ecological precision, and inclusive governance—are imperative. Central to this paradigm is adaptive management, an evidence-driven cycle of planning, monitoring, evaluation, and adjustment essential for addressing the uncertainties inherent in dynamic desert socio-ecological systems [52,53]. In Ash Meadows, the adaptive governance model combines participatory monitoring—engaging federal agencies, tribal entities, NGOs, and local stakeholders—with structured feedback loops that have refined invasive species control and spring restoration strategies in response to ecological change [38,54]. This iterative co-management approach reflects polycentric governance and co-learning principles, whereby local and indigenous knowledge are integrated with scientific monitoring and regulatory oversight to guide restoration in real time [55,56]. Consequently, the Ash Meadows initiative underscores that successful NBS in desert regions hinge not merely on technical design, but on resilient systems that integrate continuous learning, stakeholder empowerment, and institutional adaptability to navigate socio-ecological transformations under climate stress.

3.4. Nature-Based Solutions in the Eastern Province of Saudi Arabia

The Eastern Province of Saudi Arabia, encompassing cities such as Dammam, Dhahran, and Al-Khobar, has undergone dramatic socio-spatial transformations over the past century (Figure 5 and Figure 6,

Table 4. Quantitative landscape profile of the Eastern Province of Saudi Arabia and Al-Khobar.

Category	Indicator
Geographic and Climatic Scope
Location	Eastern Province, Saudi Arabia (including Al-Khobar, Dammam, Dhahran)
Coastal length	~40% of Saudi Arabia’s coastline (~1000 km)
Climate type	Hyper-arid coastal desert
Annual precipitation	<100 mm
Summer temperatures	Frequently >45 °C
Evapotranspiration rate	2500–4500 mm/year
Environmental Baseline
Major ecosystems	Mangrove forests, sabkhas (salt flats), wetlands, desert plains
Groundwater stress	Over-extraction and seawater intrusion common
Urban heat island	Severe due to industrial activity and urban sprawl
Soil conditions	High salinity, low organic matter, fragile structure
Protection Interventions
Mangrove reforestation	>30 million Avicennia marina (Grey Mangrove) trees planted (Aramco, since 1993)
Area under mangroves	~60 km2 along Eastern Province coastline
Carbon sequestration	Up to 5× more than terrestrial forests
Additional initiatives	Abu Ali Island: 1200 ha targeted by 2030
Sustainable Management
Urban green infrastructure	Modon Lake in Al-Khobar (powered by treated wastewater, surrounded by 760 palms)
Health benefits	Green space access correlated with physical and mental health (r ≈ 0.43–0.47)
Irrigation source	Treated wastewater
Challenges	High evapotranspiration, canopy loss, water quality and infrastructure limits
Restoration and Creation
Coastal development	Corniche redevelopment with mangrove patches and pedestrian zones
Green space expansion	Urban parks and shaded corridors introduced in Al-Khobar
Hydrological interventions	Limited; mostly engineered systems for urban cooling and aesthetics
Governance and Monitoring
Institutional structure	Centralized water and land governance; limited local authority
Vision 2030 alignment	Supports ecological restoration, green infrastructure, and urban resilience
Participatory mechanisms	Emerging but limited; top-down implementation dominant
Monitoring tools	Inconsistent; hydrological and ecological data often lacking
Challenges and Trade-offs
Water resource risk	Treated water dependence may face future shortages
Salinity impacts	Plant survival threatened without adaptive irrigation and soil treatments
Institutional rigidity	Top-down planning resists flexible, iterative NBS design
Opportunities and Innovations
Green Initiative goals	SGI targets: 10 billion trees and 40 million ha rehabilitation nationally
Knowledge integration	Traditional systems (e.g., hima) potential for adaptive co-management
Technological support	Aramco, KFUPM, and KAUST involved in ecological monitoring and modeling

), transitioning from small fishing and pearling communities to a highly urbanized and economically strategic region [57]. Al-Khobar, in particular, evolved from a modest port town into a major urban node in the wake of oil discoveries in the 1930s, driven by the infrastructural development led by ARAMCO and later consolidated by national urban expansion programs [58,59]. The city’s morphology reflects a blend of American suburban planning and Gulf urbanism, characterized by low-density, car-dependent layouts, zoning segregation, and widespread land reclamation along the coast [60]. This rapid urban growth, while economically transformative, has placed immense pressure on fragile desert ecosystems and groundwater reserves in the region.

Ecologically, Al-Khobar is situated within a hyper-arid climate zone, with mean annual precipitation rarely exceeding 100 mm and summer temperatures frequently surpassing 45 °C [63]. These extreme conditions contribute to high evapotranspiration rates and frequent water stress, which, when coupled with urban impermeability, intensify the risk of flash flooding and microclimatic heating. The city is also bordered by sabkhas—coastal salt flats that are ecologically unique but vulnerable to urban encroachment and groundwater salinization due to seawater intrusion and over-extraction [60,63]. These environmental pressures underscore the need for integrated planning approaches such as Nature-Based Solutions (NBS), which align ecological restoration with urban sustainability. Furthermore, Al-Khobar’s development trajectory is increasingly influenced by Vision 2030 initiatives aimed at enhancing livability, environmental quality, and resilience through green infrastructure, water-sensitive design, and context-specific adaptation strategies [59]. Therefore, understanding the city’s biophysical and socio-ecological context is critical to formulating effective NBS interventions tailored to arid urban environments.

The Eastern Province—and Al-Khobar in particular—offers a compelling study of Nature-Based Solutions (NBS) in hyper-arid urban contexts, showcasing how tailored protection, sustainable management, and restoration/creation interventions can be integrated—and where they face critical challenges (

Table 5. Comparative synthesis of the three international dryland case studies.

Case Study	IUCN Typology Application	Systems-Based Frameworks (Ecological, Social, Governance Integration)	Key Insights
Loess Plateau, China	Protection: Preservation of native vegetation and watershed buffers [28]—Sustainable Management: Terracing, agroforestry, controlled grazing [26]—Restoration/Creation: Afforestation of >35,000 km2 and sediment control [25]	Initially centralized, top-down planning—Later integrated ecological monitoring and farmer compensation incentives [28]	Delivered major ecological gains (soil C ↑60%, sediment ↓100 Mt/year), but faced groundwater depletion due to monoculture afforestation
Mojave Stewardship, USA	Protection: Land designation under the California Desert Protection Act (MDLT, 2023)—Sustainable Management: Native seed zones and ecological restoration [38]—Restoration/Creation: Bioswales, wildlife corridors in urban areas [38]	Polycentric governance: USFWS, BLM, tribes, NGOs—Use of seed-adaptation trials and community-run nurseries—Digital decision tools [42]	Represents adaptive NBS with flexible governance and ecological specificity, though scaling seed supply remains challenging
Ash Meadows, USA	Protection: Ramsar wetland protection and legal acquisition (USFWS, 2025)—Sustainable Management: Invasive species removal and spring restoration [42]—Restoration/Creation: Channel reconfiguration and aquifer reconnection [61]	Participatory monitoring with tribal and federal collaboration—Aquifer-focused management with cross-jurisdiction coordination	High ecological precision and legitimacy at smaller scales; demonstrates strong integration of hydrology and participatory governance

).

Protection interventions in the Eastern Province are focused primarily on coastal mangrove conservation, representing a critical natural boundary between urban expansion and marine ecosystems. Saudi Aramco’s mangrove planting initiative, launched in 1993, has grown to over 30 million Avicennia marina saplings across approximately 60 km² of the Eastern coastline, enhancing carbon sequestration—by up to five-fold compared to terrestrial forests—and providing vital nursery habitats for marine species and coastline stabilization [20,64,65]. Complementary initiatives, such as the Abu Ali Island carbon sequestration project, aim to plant over 1200 ha by 2030, supporting Vision 2030 and the Saudi Green Initiative targets [20,66]. However, effective protection requires more than large-scale planting; it depends on hydrological monitoring and policy measures. Critics caution that without legal coastal zoning and adaptive water management, plantings may underperform or degrade, particularly under salinity fluctuations and development pressures [17].

Peri-urban Al-Khobar and neighboring Dammam present sustainable management interventions through green infrastructure, aiming to optimize ecosystem services in urban settings. The establishment of Modon Lake—an artificial reservoir powered by treated wastewater and surrounded by green promenades and 760 palm trees—has enhanced urban cooling, biodiversity, and social well-being [67]. In parallel, studies in the Eastern Province show strong correlations between green space access and improved physical, mental, and social health (r ≈ 0.43–0.47) [68]. However, management efficacy is constrained by high evapotranspiration (2500–4500 mm/year), which leads to seasonal canopy loss and necessitates drought-adaptive species and irrigation strategies [69]. Additionally, the reliance on treated wastewater, while resource-efficient, raises sustainability concerns if reuse infrastructure and maintenance are not institutionalized [70].

Restoration and creation efforts in Al-Khobar highlight engineered ecosystems meant to recapture lost ecological functions within urban space. Projects transforming coastal corniche zones and recreational parks integrate mangrove patches, pedestrian infrastructure, and microclimatic design elements [71,72]. These efforts offer public engagement and environmental recreation, but their sustainability is highly contingent on stable water supplies and institutional maintenance. They often function more as engineered green amenities than self-sustaining ecosystems, raising key questions over long-term viability and water resource demands under resource constraints [20,73].

Figure 6. The location and features of the Eastern Province. Sources: [74,75,76].

Figure 6. The location and features of the Eastern Province. Sources: [74,75,76].

Urban greening and coastal restoration initiatives in the Eastern Province (Figure 6)—including extensive mangrove planting by ARAMCO and the establishment of Modon Lake in Al-Khobar—demonstrate a strong alignment with the IUCN framework’s three pillars: protection, sustainable management, and restoration/creation. However, the shortcoming lies in governance systems that remain overly siloed and top-down, which may undermine ecological tenets. For example, ARAMCO’s planting of over 30 million mangrove trees enhances coastal resilience and carbon sequestration [65], but without hydrological monitoring and coastal zone planning, these systems can suffer from declining groundwater or salinity stress—threatening long-term viability [17]. Similarly, Modon Lake’s use of treated wastewater for urban cooling [68] exemplifies sustainable management and restoration, yet its reliance on institutional maintenance and stable water sources poses risks. If governance frameworks do not include adaptive oversight, these engineered systems may fail under future drought or management lapses [69,70].

4. Discussion

When assessed through the dual lenses of the IUCN’s tripartite typology and systems-based frameworks, the Loess Plateau, Mojave Stewardship, and Ash Meadows cases reveal both convergences and divergences that illuminate critical design principles for implementing Nature-Based Solutions (NBS) in desert contexts. All three interventions exemplify the IUCN framework: the Loess Plateau integrated protection of native vegetation, sustainable land-use shifts through agroforestry and grazing management, and large-scale ecological restoration; the Mojave Stewardship secured conservation land, applied adaptive revegetation protocols, and implemented urban–periurban green infrastructure; and Ash Meadows combined legal wetland protection, invasive species removal, and hydrological restoration to recover endemic biodiversity. However, these cases diverge in the depth of systems-based integration (Table 5). The Loess Plateau, while achieving large-scale ecological gains, initially overlooked water-use dynamics and species specificity, leading to ecological trade-offs such as groundwater depletion—highlighting the limitations of rigid, top-down planning [33,34]. In contrast, the Mojave initiative showcases an adaptive co-governance structure involving scientific institutions, tribal communities, and federal agencies, enabling flexible and iterative responses to ecological uncertainty [38,46]. Ash Meadows, though smaller in spatial scale, demonstrates perhaps the most refined systems-thinking: its participatory monitoring, aquifer-level hydrological restoration, and inclusive decision-making structures model a polycentric governance framework that enhances resilience [77,78]. These comparative insights affirm that while the IUCN typology offers a valuable structuring device for NBS, its efficacy in arid landscapes hinges on being embedded within systems-based, socially anchored, and ecologically adaptive governance architectures.

Applying these lessons to the Eastern Province of Saudi Arabia highlights both the potential and the challenges of transferring international NBS experience to a hyper-arid, rapidly urbanizing coastal context. Ecologically, the province’s mangrove restoration, wetland rehabilitation, and sustainable urban landscaping initiatives align with the IUCN framework and reflect growing policy attention through Vision 2030 and the Saudi Green Initiative. Yet, as with the Loess Plateau, projects risk overreliance on large-scale planting without fully accounting for hydrological limits, particularly in areas experiencing rising salinity and constrained freshwater availability. Lessons from the Mojave and Ash Meadows cases suggest that species selection should be tightly coupled with hydrological monitoring and adaptive planting densities, while governance arrangements must be capable of adjusting water inputs and management strategies in response to environmental feedback.

Governance emerges as a decisive factor in determining the long-term viability of NBS in the Eastern Province. The comparative cases demonstrate that adaptive, inclusive governance structures—whether through polycentric arrangements, community co-management, or participatory monitoring—enhance the resilience of NBS in arid landscapes. In contrast, the province’s current centralized water and land-use governance limits local stewardship and constrains iterative decision-making. While this presents a barrier to embedding flexible frameworks, emerging policy signals—including Vision 2030 commitments, SDG 11 localization, and evolving water governance frameworks—indicate a potential shift toward more integrated and decentralized planning [72,79,80,81]. Incorporating elements of traditional ecological practice, such as the hima system, with modern monitoring technologies could provide culturally grounded pathways for enhancing local engagement and ecological legitimacy.

Trade-offs are inevitable in hyper-arid NBS implementation and must be addressed explicitly in planning and governance frameworks. The Loess Plateau’s monoculture afforestation demonstrates the ecological cost of prioritizing rapid vegetative cover over species diversity and hydrological sustainability. Conversely, the Mojave and Ash Meadows cases show that scaling can be achieved through ecological specificity and iterative adaptation, albeit with constraints such as seed supply and predator management. For the Eastern Province, balancing ecological ambition with water resource limitations will require multifunctional designs that deliver biodiversity benefits, climate regulation, and urban livability while remaining hydrologically sustainable.

Advancing NBS in the Eastern Province therefore depends on integrating the conceptual structure of the IUCN typology with the operational flexibility of systems-based governance. The comparative cases from the Loess Plateau, Mojave Stewardship, and Ash Meadows show that ecological outcomes in arid contexts are maximized when restoration, sustainable management, and protection measures are coupled with adaptive, multi-level governance and informed by continuous hydrological monitoring. Translating these lessons to the Gulf context requires careful adaptation—species selection and planting densities must be linked to local water budgets, governance arrangements need to accommodate cross-sectoral coordination, and community engagement should be embedded from the outset.

In Al-Khobar and the wider Eastern Province, NBS are still in formative stages, but they exhibit strong potential through initiatives such as mangrove restoration, sustainable urban landscaping, and wetland rehabilitation. The primary constraints—water scarcity, institutional fragmentation, and socio-cultural perceptions—can be addressed by leveraging opportunities for treated wastewater reuse, revitalizing coastal habitats, and integrating indigenous ecological practices into modern urban planning. This requires governance that is polycentric in design yet coherent in vision, enabling both national-level coordination and local-level stewardship.

By connecting the lessons of diverse international experiences to the specific socio-ecological conditions of the Eastern Province, this study sets the stage for a framework that is at once typologically clear and adaptively managed. Yet the real value of this framework lies not only in theoretical integration but in its ability to generate concrete, transferable strategies for planners and policymakers working in hyper-arid urban environments. To clarify these contributions and provide strategic guidance, the following subsection distills the comparative analysis into a concise set of lessons and synthesized principles that highlight how Nature-Based Solutions can be effectively designed, governed, and scaled in Saudi Arabia and other desert cities.

4.1. Strategic Lessons for Hyper-Arid NBS Implementation

Synthesizing ecological outcomes, governance approaches, and implementation challenges across the Loess Plateau, Mojave, Ash Meadows, and Eastern Province cases reveals several strategic lessons. These lessons move beyond descriptive accounts of individual projects to provide actionable guidance for hyper-arid cities, where the success of NBS depends on aligning ecological design with adaptive governance and socio-cultural legitimacy. The distilled insights can be articulated as a set of interrelated strategies that highlight the critical conditions for successful planning and implementation, offering a practical roadmap for both policymakers and practitioners (

Table 6. Strategic Synthesis of NBS Cases for Hyper-Arid Contexts.

Case Study	Ecological Strategy	Governance Approach	Key Constraints	Transferable Lessons for Hyper-Arid Cities
Loess Plateau (China)	Large-scale soil conservation, afforestation, agroforestry	Initially centralized, later more decentralized with farmer incentives	Groundwater depletion from monocultures	Couple restoration with water balance monitoring; avoid over-reliance on non-native species
Mojave Stewardship (USA)	Native plant restoration, bioswales, wildlife corridors	Polycentric governance (federal, tribal, NGOs); adaptive decision-support tools	Seed supply shortages, drought stress	Prioritize ecological specificity; embed participatory governance; develop digital tools for scaling
Ash Meadows (USA)	Hydrological restoration of desert springs, invasive species control	Polycentric governance; participatory monitoring and adaptive co-management	Reliance on external funding; aquifer vulnerability	Legal protection plus hydrology-driven restoration; iterative co-management to sustain ecosystems
Eastern Province (Saudi Arabia)	Mangrove restoration, wastewater-fed urban greening, corniche redevelopment	Centralized, top-down governance; emerging Vision 2030 frameworks	Institutional fragmentation, limited hydrological monitoring	Link NBS to national sustainability goals; integrate treated wastewater reuse; pilot participatory frameworks

):

• Hydrological integration is essential—Afforestation and restoration efforts must be explicitly coupled with water balance monitoring and adaptive irrigation to prevent ecological failure under arid conditions.
• Species selection must prioritize ecological specificity—Native and climate-adapted species (xerophytes, halophytes) ensure higher survival rates and reduce long-term maintenance burdens.
• Governance frameworks determine success or failure—Polycentric, inclusive governance (e.g., Mojave, Ash Meadows) sustains ecological outcomes more effectively than rigid top-down structures (e.g., current Saudi context).
• Adaptive management enhances resilience—Iterative monitoring, feedback loops, and community participation allow projects to respond to ecological uncertainty and socio-political change.
• Socio-cultural legitimacy strengthens longevity—Incorporating traditional systems (e.g., hima grazing reserves) and aligning with local values increases public support and stewardship capacity.
• Urban hyper-arid NBS require multifunctionality—Beyond ecological benefits, interventions must deliver cooling, recreation, and health outcomes to gain traction in rapidly urbanizing desert cities.

5. Conclusions

The theoretical exploration of Nature-Based Solutions (NBS) in this study highlights the need to unite ecological integrity with adaptive governance in arid urban contexts. The adoption of the International Union for Conservation of Nature (IUCN) tripartite typology—protection, sustainable management, and restoration/creation—proved valuable in structuring the classification of interventions. However, the findings show that its effective application in hyper-arid settings requires integration with systems-based frameworks capable of addressing the non-linear dynamics of desert ecosystems, socio-ecological feedback loops, and evolving governance structures. To translate these insights into practice, the comparative analysis was distilled into a set of strategic lessons (Section 4.1), providing concise guidance on hydrological integration, adaptive governance, and socio-cultural legitimacy. This synthesis strengthens the contribution of the study by bridging conceptual models with practical strategies for policymakers and practitioners in hyper-arid cities. This integration responds to the first research question by demonstrating that the typology alone is insufficient; it must be applied through iterative, multi-level planning processes that incorporate hydrological modeling, stakeholder engagement, and policy adaptability.

The comparative analysis of the Loess Plateau in China, Mojave Stewardship in California, and Ash Meadows National Wildlife Refuge in Nevada addresses the second research question by revealing the principles and limitations of international experience. The Loess Plateau demonstrates how large-scale restoration can deliver significant ecological gains but also warns of the risks of hydrological oversimplification. The Mojave case illustrates how participatory governance, ecotypic plant restoration, and adaptive management tools can sustain NBS in complex, multi-jurisdictional settings. Ash Meadows shows the value of legal protection and hydrology-driven restoration in safeguarding sensitive groundwater-fed systems. These cases together indicate that successful NBS in desert contexts depend on aligning ecological design with governance frameworks that are both socially inclusive and ecologically adaptive, while also tailoring approaches to local environmental conditions.

The application of this integrated framework to the Eastern Province of Saudi Arabia, particularly Al-Khobar, provides the basis for answering the third research question. While current NBS initiatives—such as mangrove restoration, sustainable urban landscaping, and wetland rehabilitation—are at an early stage, they are aligned with the IUCN typology and national goals under Vision 2030. Yet, empirical findings from the Saudi case reveal persistent institutional fragmentation, an overreliance on centralized, top-down implementation, and limited hydrological monitoring as key constraints. These weaknesses risk undermining ecological performance and long-term viability if not addressed systematically. At the same time, emerging governance innovations—including cross-sectoral coordination platforms, ecological data integration, and pilot participatory frameworks initiated under Vision 2030—signal a potential shift toward more adaptive, inclusive, and evidence-based approaches. This duality—constraints alongside emerging opportunities—offers a critical insight for scholars and practitioners seeking to operationalize NBS in hyper-arid contexts.

The scientific contribution of this study lies in bridging the gap between theoretical typologies and the practical realities of implementation in desert cities. It demonstrates that the IUCN model gains transformative value only when coupled with governance frameworks that enable adaptive management, institutional flexibility, and socio-cultural legitimacy. In this respect, the study enriches sustainability science by showing how international experiences can be reframed to inform context-specific interventions in the Gulf, advancing both theoretical understanding and applied practice.

Looking forward, the study identifies several priorities for future research that can consolidate and extend its findings. First, there is a pressing need to quantify hydrological impacts of NBS interventions, particularly their effects on groundwater depletion, salinity dynamics, and treated wastewater reuse under hyper-arid conditions. Second, further work should focus on developing adaptive governance models tailored to Gulf-region cities, emphasizing cross-sectoral coordination, participatory monitoring, and iterative adjustment of policy frameworks. Third, integrating traditional ecological knowledge systems—such as the hima grazing reserves—into modern planning can enhance legitimacy, continuity, and local stewardship of ecological infrastructure. Fourth, more attention is required to socio-cultural perceptions of nature in desert societies, as community engagement and public acceptance will ultimately shape the sustainability and scalability of interventions.

In conclusion, this research demonstrates that embedding NBS in hyper-arid urban contexts requires both the conceptual clarity of the IUCN typology and the operational flexibility of systems-based frameworks. By combining theoretical synthesis, empirical lessons from diverse arid landscapes, and context-specific application in the Eastern Province, the study offers a practical and adaptable approach for designing, implementing, and scaling NBS that are ecologically sound, socially inclusive, and institutionally resilient—qualities essential for responding to climate instability and rapid urbanization in dryland regions worldwide. Its findings emphasize that the future viability of NBS in hyper-arid regions rests in their ability to evolve as dynamic socio-ecological systems—capable of absorbing climatic shocks, overcoming institutional fragmentation, and fostering inclusive governance mechanisms aligned with long-term sustainability goals.