The availability and accessibility of clean freshwater are particularly critical in drylands, where it is a key life-limiting factor. Water security encompasses the reliable access to a sufficient quantity and quality of water to ensure a healthy lifestyle [16]. Conversely, water insecurity relates to the state of unsustainable, nonreliable, insufficient, contaminated [17], or saline water [18], which does not meet the necessary standards for use by humans. Extreme climatic events, especially long-term droughts and unpredictable precipitation regimes, aggravate water insecurity and accelerate land degradation and desertification [19]. In high mountainous dryland regions, such as Central Asian countries, increasing temperatures over the long-run have led to accelerated retreat of glaciers, simultaneously threatening water and food security for rural populations who rely on the melting water for irrigation of vegetable and fruit tree crops [20]. Across the Mediterranean Basin, recurrent drought episodes increase the severity of water scarcity. Managing decreased water resources becomes particularly challenging when associated with other pressures, such as population growth and higher agricultural demand. The imbalanced distribution of water resources among the different users often leads to disputes, tensions, and violence [21].

Water scarcity is self-evidently the most important factor that limits food production in drylands. Practically, water security directly influences food security by regulating net primary productivity, crop yields, and forage production, thus influencing availability of food for humans [16] and fodder for livestock. Simultaneously, food production affects water security by increasing irrigation demands for crops, and water demands for livestock [22]. Thus, water security and water-use efficiency (also named water productivity) are both key factors with potentially significant impacts on food security [23]. Further, agricultural or livestock-derived wastewater considerably lowers the quality of surface water and groundwater [17]. Moreover, when pumping water from nonrenewable or slow-recharge underground aquifers, their level declines over time, causing consequent harm for long-run agricultural production [24]. Regardless, mismanagement of irrigation water may cause secondary salinization and sodification of extensive lands, resulting in land degradation and desertification, and decreasing crop yields [25]. Another aspect is the use of large quantities of fresh water for food processing and preparation activities, further straining drylands’ limited water resources [26].

Water security is a bidirectional variable: it affects and is affected by environmental-security-related issues. For example, water allocation for human needs, involves a trade-off for water allocation for natural ecosystems. Moreover, water contamination adversely affects both environmental and human health [27]. Water security also interrelates with energy security, as hydroelectric discharge converts energy to electricity. Hydroelectric power plants produce clean energy, and simultaneously improve reliability of water provision for human needs [28]. However, flooding of extensive areas upstream of hydroelectric dams inundates natural habitats, may demolish ecosystems, and degrades extensive lands. Simultaneously, these plants considerably change the downstream flow, degrading water quality and harming flora and fauna, sharply decreasing biodiversity [29]. Moreover, dam construction affects human rural populations by uprooting them, degrading their living conditions, decreasing their socioeconomic status, and lowering their access to food [30].

Environmental security aims at protecting the environment from risks predominantly caused by anthropogenic factors such as accidents, mismanagement, inappropriate design, or ignorance. The key elements of environmental security include preventing natural and anthropogenic damage to the environment, and restoring damages to support human, material, and natural resources at multiple levels, ranging from local to global [31]. Preventing environmental pollution is particularly important. Whether caused by agrochemicals, municipal and industrial sewage sludges, livestock manure (including traces of antibiotics and other medications), or other sources, the implications are adverse for human health and necessitate the restoration of contaminated sites and resources [32].

Land-use change and deforestation for establishing new croplands and grazing lands have led to biodiversity loss, accelerated soil erosion, depletion of soil organic carbon pools, secondary salinization, pollution, eutrophication of water sources, and the overall degradation of soil functions and ecosystem services. Consequently, the potential productive capacity of extensive lands has diminished, lowering agricultural yields and forage production [33], and exacerbating food insecurity. Furthermore, land-use change is responsible for approximately 22% of the global emissions of greenhouse gases (GHGs); 13% of the total GHGs are emitted from newly converted lands. Of these, methane (CH₄) from enteric fermentation is responsible for over one-third, nitrous oxide (N₂O) from manure and synthetic fertilizers is responsible for 15%, and 11% comes from CH₄ emissions from paddy rice cultivation [34]. In turn, the increasing GHG concentrations aggravate climatic changes, where the consequent growing frequency and magnitude of severe droughts and devastating floods further lessens potential agricultural productivity and food security [35]. The world’s growing population—mostly in regions that already struggle to feed their populations—further exacerbates these environmental threats [4].

Environmental security issues related with agricultural land-use may have strict impacts on human health, for example, through the enrichment of aboveground and underground water sources with excess agricultural nutrients, herbicides, pesticides, insecticides, and fungicides [36]. Similarly, excess manuring may infect these water sources with pathogenic microorganisms and viruses [37]. The use of these aquatic bodies as a source of drinking water may impose serious health risks to human populations. Specifically, contamination of water sources with nitrogen fertilizers has proved to be carcinogenic, both for children and adults [38]. Further, deforestation and the loss of natural lands are known to facilitate the spread of diseases by transferring pathogens from wildlife to humans. For example, this mechanism was proposed as one of the main factors causing many epidemics such as Ebola, AIDS, SARS, avian influenza, and swine flu, as well as for the recent outbreak of the coronavirus (COVID-19; [39]).

Environmental security has long ago been recognized as an integral part of human security, and an important factor in determining national security [40]. Recent history suggests that climate change and environmental security-related hazards can fuel societal conflicts and political unrest. Violence and instability may, in turn, result in mass outmigration, augmenting environmental threats and food insecurity [11,31].

Energy security has multiple definitions, most of which include the dimensions of energy availability, affordability, capacity, and sustainability [41]. Energy security critically interacts with factors such as climate, water, food, governance, human health, human rights, and national security. Seeking energy security impacts food security in two major ways, i.e., through agriculture’s reliance on fossil fuels [42], and the bioenergy–food competition [43]. Industrialized agriculture, which relies on fossil fuels, contributes approximately 10% to total GHG emissions. Emitted GHGs exacerbate global temperature rise and climatic instability, threatening food production [44]. Simultaneously, land-use changes and pollution associated with extracting, processing, and transporting fossil fuels undermine ecosystem services [45]. Rising demands for food, energy, and their increasingly interlocked markets [46] threaten the global food system as oil supply and agricultural intensification drive food price volatility and food insecurity [42].

Contradictions between energy security and other security dimensions may arise. For example, although collection of native woody vegetation for fuelwood alleviates energy insecurity at the household level, it simultaneously accelerates soil erosion, land degradation, and desertification [47]. Similarly, the excessive use of crop residue and livestock manure as fuel depletes soil organic carbon pools and lowers nutrient cycling, degrading the quality and fertility of soils [48]. As a consequence, cropland degradation is accelerated, decreasing agricultural productivity and increasing food insecurity. Further, using these materials for cooking and heating degrades environmental security through the increase in toxic gas emissions and particulate air pollution, and adversely affects health security by causing respiratory-related diseases [49]. Large-scale bioenergy cropping systems, although aimed at energy self-sufficiency and GHG emission mitigation, often compete with food and feed crops for land, water, and fertilizers, aggravating food insecurity and inflating food prices [42,43]. The 2008 global food crisis and ensuing political instability in some parts of the world were partly caused by expansion of the bioenergy industry [46]. This sector also drives environmental insecurity by promoting deforestation for the establishment of bioenergy systems [50], accelerating land degradation and release of GHGs. Some industrialized countries address their own energy security concerns by acquiring large tracts of land for bioenergy cropping in lower-income countries [51], where the already impoverished local communities may lose tenure rights over their lands, be displaced, and face aggravated food insecurity [52]. Yet, certain tracks of the bioenergy sectors—such as pyrolysis of organic waste materials—may be perceived as environmentally friendly, as they are considered carbon-neutral and even carbon-negative processes, while converting wastes into resources. In addition to the production of a flammable gas that can be used as a fuel, pyrolysis coproduces biochar that can be utilized as a soil amendment. It has been shown that applying biochar in soils of croplands [53], rangelands [54], and tree-based systems, such as forestry projects, agroforestry systems, and fruit tree orchards, improves their productive capacity [55], thus increasing economic and food security of local populations.

Other sources of renewable energy can reduce the stresses imposed on either native- or cultured-plant biomass. For example, producing solar energy using photovoltaic panels has become very widespread, particularly in off-grid and remote rural areas [56]. While small- and domestic-scale operations are considered environmentally friendly, the establishment and maintenance of large-scale and commercial solar farms may lead to the degradation of extensive lands, adversely impacting environmental [57] and food security. A possible measure for mitigating these adverse impacts is the subsector of agrivoltaics, which enables the use of the very same lands for photovoltaic panels and agricultural crops [58]. The emerging wind energy sector encompasses another alternative for bioenergy [59]. Yet, serious human rights issues are associated with this sector. For example, private enterprises or corporations—often supported by governments or international firms—dispossess local communities from extensive lands in order to establish large-scale turbine farms. Specifically, across the Global South, this forced land expropriation limits the access of local populations to their communal pasturelands and risks their tenure rights, acquisitions, and possessions. As a consequence, household-level food security is threatened [60]. Further, wind turbines may potentially risk health security. For example, the audible noise and low frequency sound of the turbines’ rotating blades were reported to be potentially harmful to human health, and vision problems are occasionally caused by the turbines’ shadow flicker [61]. In addition, wind turbines are responsible for fatal bird collisions, causing mass mortality of birds worldwide, thus raising their environmental footprint and further questioning their sustainability [59].

According to the International Committee of the Red Cross, economic security refers to “the ability of individuals, households or communities to cover their essential needs sustainably and with dignity” [62]. Economic security has direct implications for guaranteeing food security. The livelihoods of many dryland populations rely on natural resources that often deteriorate due to harsh climatic conditions and low-fertility soils. Further, many people become food-insecure because of severe political crises or conflicts, which disrupt economic and agricultural activities and contribute to food price shocks and wide economic insecurity [63]. Strictly speaking, these aspects are indirectly linked to food availability. Although sufficient food can be transported to the affected areas, conflicts and political tension still disrupt food supply. For example, in 2017, food prices spiked due to conflict situations in sub-Saharan dryland countries such as Nigeria, South Sudan, and Burundi [64].

Climatic changes pose specific economic security challenges for rural populations in dryland countries, often dependent on rain-fed agriculture as their main source of income [65]. Uncertain rainfalls, long-term droughts, increasing temperatures, and frequent floods adversely affect the ability to produce nutritious and sufficient food [66]. In the Sahel and eastern African drylands, where natural capital and agriculture are the backbone of many economies, agricultural activities and economic security are strongly interconnected [67]. Further, climate change also affects global-scale economic security. For example, in 2011, crop failure in China due to drought led the country to buy wheat on the international market. This caused global wheat prices to increase. Specifically, in Egypt, the world’s largest wheat importer, the inflated wheat price tripled bread prices. This triggered a serious economic crisis and caused civil unrest [68].

Regardless, poverty and lack of access to modern markets and infrastructures push local populations towards excessive use of natural resources for energy, accelerating deforestation and clearing of native vegetation from extensive lands [69]. In turn, severe land degradation aggravates the vulnerability of these populations to extreme environmental conditions, which can easily trigger humanitarian crises. For instance, the 2011 east African drought resulted in widespread famine and over 250,000 deaths. In the 2017 drought, fatalities were avoided as a result of the timely and substantial response of the international aid community [70]. By 2030, if temperatures rise by 1.5 °C, it is predicted that an additional 122 million people will experience extreme poverty as a result of increased local, regional, and global food prices [71]. As recurring food crises slow economic growth, effective interventions should aim at simultaneously sustaining food- and economic-security. The current COVID-19 pandemic demonstrates this need [72]. A new composite Proteus Index for measuring the multidimensional concept of food security clearly shows the relations between food security and economic and health dimensions of welfare [73]. Specifically, higher energy and retail prices, alongside reduced incomes due to lockdowns, further coupled with disruption of local markets due to the COVID-19 pandemic, has exacerbated the vulnerability of households in low- and middle-income countries [74].

Climate change impacts on food systems pose risks to human health [75]. For example, resilient immune systems depend on nutritionally adequate diets, both in terms of quantity and quality [76]. A stable provision of nutritious food is essential for human health and vitality. At the same time, those affected by insecure food provision commonly shift to less healthy diets and consume unsafe foods [77]. Undernutrition and food insecurity are key signifiers of a compromised health status, increasing and compounding the risk of chronic disease and poor mental health, particularly in children and adolescents [78]. Further, health hazards associated with extreme weather and climate are increasing globally [75], and cascade with the inputs of systemic risks. For example, the COVID-19 pandemic started as a health crisis, but quickly trickled through socioeconomic, technological, financial, and food systems. Lockdown measures aimed at ensuring health security interrupted global food supply chains, leading to food shortages. While products could not be transported to markets, food was often wasted [79]. Further, COVID-19 is likely to annihilate much of the progress achieved over the last few decades regarding women and children’s nutrition. The expected increased numbers of stunted children will compromise their future human capital and economic productivity, further reducing their food security [74]. As climate change is likely to increase the frequency of pandemics in the future [80], ensuring access to nutritionally adequate diets should gain a particular urgency in the context of public health [81].

In addition to the health impacts caused by food insecurity, heat exposure is expected to become a serious issue under climate change. The IPCC showed that the increase in annual maximum daytime temperature will affect rural and urban communities, particularly in low- and middle-income countries [82]. Clinical effects of heat exposure include reduced performance and work capacity, strain on cardiovascular systems, heat stroke, morbidity, and mortality [83]. Further health-related impacts from climate-change-related stresses include the geographic expansion of vector-borne pandemics, including malaria, dengue fever, chikungunya, yellow fever, and the Zika virus [82].

Climate change decreases the capacity of health systems to manage the alterations in frequency and intensity of climate-sensitive health outcomes [82]. The impacts of climate change on resilience of health systems vary among countries, as do demographic structures, socioeconomic characteristics, infrastructural effectiveness, and institutional capacities. Specifically, low-income countries that are already disproportionately affected by climate change impacts and are likely to experience more severe impacts to their domestic food systems, face severe exacerbation of existing challenges to health security [75]. Strong adaptation strategies and policies can help reduce the impacts of climate change on human health [44]. Particularly, adaptation schemes should aim at systematically enhancing the capacities of local health systems and communities to adjust, respond, and adapt to increasing climate-related health effects [75].

Governance has been explored in different disciplines as an inclusive perspective at the sociopolitical arena [84]. Examining the interface among water security, environmental security, energy security, economic security, health security, and food security governance highlights the multiple and complex connections among them, with drylands identified as being particularly fragile systems. These interdependencies display the importance of governance as an intermediary agent. Since governance is a normative- and narrative-based concept that strongly focuses on ideal types rather than current practices [85], we suggest defining food security governance as simultaneously ensuring food availability, access, utilization, and stability through effective administration and regulation by multilevel authorities.

Good governance sustains infrastructures and services for wide populations [84]. It also serves as a platform for reconciling conflicting interests related to land-use and utilization of natural resources, for assessing needs, and for more fairly distributing and allocating resources in cases of water scarcity or food shortage [86]. An additional aspect of good governance is allowing more people to participate in decision-making procedures, increasing transparency and strengthening equity [87]. Good governance, whether focusing on practices, solutions, or technologies, is evident in system effectiveness, resulting in shorter periods and lower intensities of food insecurity phases, and faster recovery from crises [86]. Conversely, poor governance contributes to additional losses of food for human consumption [67] and reduces the ability to cope with food crises. These effects are exacerbated in places where land degradation and desertification occur, in which food production is already at risk.

Moreover, it has been demonstrated that poor governance of natural resources may accelerate processes of biodiversity loss, land degradation, and desertification, adversely affecting agricultural productivity and exacerbating food insecurity [88]. For example, in dryland areas of many African countries, it is evident that many public and national infrastructures are unmaintained and deteriorating. Failing public electricity systems encourage the widespread use of coal-fed cookstoves in many lower-income countries, simultaneously leading to deforestation of extensive lands and deterioration of public health [89]. The increasing demand for energy may provide new and more sustainable opportunities. The consensus is that governance is needed for lessening the population’s reliance on coal and wood for domestic use [90], and for redirecting investors towards renewable energy generation. Therefore, effective governance is a key point for sustaining vulnerable communities and leveraging their livelihood. Further, a holistic governance approach makes it possible to address the multiple aspects of food security. Specifically, proactive governance should promote science and technology solutions, which can play an important role in coping with the different dimensions of food security [91]. One way or another, while promoting technological, infrastructural, and legislative solutions, governance must also include local communities’ traditional knowledge, concerns, and needs, as they are inherent to human rights, social stability, and national security.