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=Climate Change and Lebanon Forests=

As in many parts of the world, the effects of climate change in Lebanon have surfaced, and are expected to have various impacts in this land over the course of the century. The impacts of climate change in Lebanon are apart of wider, global changes in climatic circumstances in recent times. Over the course of the past two centuries, industrialization, networks of fossil fuel combustion, and other anthropogenic activity has caused the movement of significant levels of carbon to the atmosphere; it is widely believed that these forms of human activity have contributed to climatic changes that have already been witnessed, and to additional climatic changes that are projected for the future.

=Climatic Changes in Lebanon= Human activity over the past two centuries has created – and will likely continue to create – shifts in components of the climate on Lebanon land. These are shifts that have already occurred, in recent decades. From 1980 to 2000 in Lebanon, there has been an upward trend in the number of days per year when temperatures exceed 35° C, an upward trend in the number of days per year when temperatures do not go below 25° C, and an upward trend in the maximum temperature reached in a given year. These are warming trends that are expected to continue. Given an “intermediate” emissions scenario, maximum temperatures in Lebanon are projected to increase by 1° C to 2° C by 2040, and 3° C to 5° C by 2090; in that year, populations are expected to experience 50 – 60 more days that exceed 30° C, as compared to a typical year one hundred years earlier. Also by the end of the century, projections suggest a potential 5° C to 6° C increase in minimum yearly temperatures across Lebanon, and 30 – 60 more days per year where the temperature does not fall below 20° C. Recent decades have also seen an overall (marginal) decrease in annual levels of precipitation. Like warming, precipitation decreases are expected to continue in Lebanon as the century unfolds. By 2040, and under an “intermediate” emissions scenario, experts envision a 10% decrease in rainfall on the coast, and a 25% decrease further into the country; by 2090, they envision a 25% decrease in annual precipitation on the coast, and up to a 45% decrease inland. These expectations for temperature and precipitation have a particular seasonality. Experts imagine that warming increases will be particularly significant in summer months; according to projections, there may be an increase in both the length and the extremity of the warmer and drier season in Lebanon. Importantly, these are trends in Lebanon that are apart of similar trends in the larger Mediterranean region – considered to be one of the most sensitive regions on Earth to global climate change. Giorgi & Lionello (2007) imagine “a collective picture of a substantial drying and warming of the Mediterranean region, especially in the warm season,” which may involve “precipitation decrease exceeding 25–30 % and warming exceeding 4–5° C” in this region. Globally, in the Mediterranean, and in various areas of Lebanon, shifts in climatic circumstances have occurred and will likely continue to occur.

=Lebanon’s Forests= Forests in Lebanon exist as they do today as a result of various anthropogenic, climatic, and other environmental forces acting over time. The geography of Lebanon can be categorized into four main regions: the coastal strip where the land meets the Mediterranean Sea, the western mountain range that runs much of the length of the country (Mount Lebanon), the Biqa Valley or central highland that is located to the east, and another mountain range further east (Anti-Lebanon). In order to understand the effects of climate change on forests in Lebanon, it is important to understand how these abiotic components of the land influence conditions within forest ecologies. Different altitudinal, topographical, and geological features shape the presence of particular bioclimatic conditions in particular Lebanon ecosystems; particular microclimates in turn come to exist in these ecosystems. “Climate change” constitutes certain effects and patterns within these microclimates – wider climatological dynamics influence levels of temperature, precipitation, and other weather patterns within these particular microclimates, which have implications for the organisms that live there.

Forests in Lebanon cover 13.3% percent of the land – about 139,000 ha. These forests are a diverse mix of forest types. Oak woodlands constitute 42% of these forests, pine forests 20%, Juniper forests 8.5%, and (the well-known) Cedar forests constitute 1.6%. These are all tree species that are indigenous to Lebanon. Within each of these forest types, the dominant tree species exists alongside a diversity of other (floral, faunal) species. Lebanon contains 4,633 species of flora. 12% of these are endemic to Lebanon, and many of these flora species reside within the forest types mentioned above.

Forests in Lebanon are vastly different today as compared to the ancient past: climatic and anthropogenic forces over time have decreased the abundance of forests in Lebanon. Various pressures and human activities (beyond the burning of fossil fuels) continue to have a degrading effect on Lebanon forest ecologies. Human settlement and land development – sometimes apart of urban sprawl – has contributed to fragmentation of regions of Lebanon forests, as humans have cleared or occupied sections of forest for development, separating one region of forest from another. Various actors in Lebanon have also historically extracted materials from forests – through logging, animal grazing, and the extraction of aromatic or medicinal plants. In various forms over time, this type of activity has caused environmental degradation in these forest ecosystems. Quarrying projects have also caused the destruction of sections of Lebanon forest, notably on Mount Lebanon. Forest fires have represented another significant detrimental pattern in Lebanon forest ecosystems: in 2007, 4000 ha of forest in Lebanon was burned, and in 2011, 25% of Lebanon’s forests were at medium risk of fire. In the second half of the 20th century, these forces interacted to create a 50% loss of total forest cover in Lebanon from 1965 to 1998. Juniper forest ecologies in Lebanon have been particularly negatively influenced by these dynamics, showing the greatest levels of degradation. Alongside these pressures, growing shifts in climatic patterns in Lebanon will likely represent an increasing challenge to the integrity of various forest ecosystems.

=Climate Change and Lebanon’s Forests: Broad Dynamics=

Forest Ecosystem Health
The effects of climate change on Lebanon’s forests have to do with the specific influences that shifting climatic forces will have on individual species functioning and overall ecosystem health. Forest ecosystems (in Lebanon and elsewhere) have varying levels of “health” or “integrity,” dependent on the internal happenings among biotic and abiotic components within the ecosystem. Components of forest ecosystem health include (biotic) structural integrity, the presence of resources (for forest organisms), soil integrity, species diversity, and other measures. The effects of human activities and climatic change on forests in Lebanon can be seen as problematic because these forces have the capacity to compromise forest ecosystem integrity, as well as the capacity of various organisms to survive, reproduce, and flourish within the ecosystem.

Ecosystemic and Individual Effects
Changes in weather patterns in Lebanon forests impact organisms both through direct influence, and through influence on the ecosystems of which organisms are apart. Shifts in climatic conditions over time will engender shifts in certain dynamics and processes of these ecosystems, creating environmental changes that in turn affect particular organisms. For example, projected decreases in precipitation and increases in water evaporation (from increased temperatures) will likely result in reductions in the availability of water in certain forests of Lebanon over the course of the next century. These climatic circumstances will interact with biotic and abiotic components of a given forest ecosystem in Lebanon – for example, the water-holding capacity of the soil, the extent of competition for water resources from other plant and animals, the topograpy of the land that influences where water travels – to produce particular effects for individual organisms. Climatic shifts will also have “direct” influences on organisms and their development. For example, changes in climate have the capacity to affect the phenology of plant species in Lebanon – or, the forms of morphological development that flora undergo in response to climatic cues. Trees and other plants “expect” certain climatic conditions as cues to develop in certain ways, often in order to reproduce. Climate change in Lebanon has the potential to bring with it shifts in when these “cues” occur, which can result in damage to parts of a tree, inabilities to reproduce for that season, or inhibited growth. These ecosystemic and individual potential effects emerge from two types of “change” that come with “climate change”: shifts in average levels of temperature or precipitation (climatic mean), and shifts in the extent to which temperature or precipitation change over briefs periods of time (climatic variability). Both factors will likely influence forests in Lebanon, at the level of the organism and at the level of the ecosystem.

Interactions between Human and Climatic Pressures
Pressures of human activity on Lebanon forests have been great, in the last fifty years and historically; effects of climate change on Lebanon forest ecologies will not occur in a vacuum, but rather will occur in interaction with these other human pressures. A report from the Lebanon Ministry of Environment describes Lebanon forests in a helpful way: “The response of natural ecosystems is multi-faceted and does not only respond to climatic parameters, but to a number of factors such as soil, topography, human interaction, pressures, site history, biotic and abiotic interactions, etc., to which climate comes as an additional stress. Thus, forest ecosystems are complex ecosystems whose response to the expected climatic variability cannot be assessed without integration a multitude of factors.” Human activities like logging, overgrazing, and quarrying have historically compromised the integrity of Lebanon forest ecosystems, and changes in climate patterns will come “as an additional stress” that interacts with these other sources of degradation. For example, for a particular Juniper stand in a region of Mount Lebanon, decreases in precipitation and/or increases in temperatures over a period of ten years may compromise the forest’s integrity in particular ways; in turn, this stand will be less resilient to pressures exerted by a quarrying company who clear cuts sections of the forest to mine minerals. In the same way, a quarrying company that compromises the integrity of this forest stand will leave this ecosystem and the organisms in it more vulnerable to the effects of ensuing decreased precipitation or increased temperatures. Climate change and other anthropogenic pressures will likely interact dialectically to challenge the integrity of forest ecologies in Lebanon, as time goes on.

Adaptation and Migration
Projections for climate in Lebanon become particularly significant for Lebanon’s forests when considering how these ecosystems and the organisms in them have come to be there. Tree species and other species in these ecosystems have evolved in part from their interaction with climatic conditions in Lebanon over time; the same can be said for these ecosystems more broadly. The organisms in Lebanon that flourish now within particular climatic conditions are able to do so because the genotypes of their species have evolved over time in ways that allow them to survive in such environments. These are evolved genotypes that have enabled survival and reproduction within historical climatological circumstances in Lebanon. Changes in climatic conditions can bring challenges to these evolved positions (of both organisms and ecosystems). Sattout and Nemer (2008) describe this dynamic: “If climate change occurs faster than the new ecosystem structure and function can be developed, the historical relationships between animal, plant and climatic conditions cannot be reestablished and biological diversity may suffer.” For forest stands in Lebanon, two “pathways” emerge from the challenges that climate change may bring to these historical positions: adaptation or migration.

At the level of the ecosystem, “adaptation” can be described as “resilience,” or, “The ability of a social or ecological system to asborb disturbances while retaining the same basic structure and ways of functioning, the capacity for self-reorganization, and the capacity to adapt to stress and change." The resilience of these ecosystems is determined by particular structural abiotic factors (e.g. soil integrity), the size of a forest stand, the diversity of ecosystems “within” a forest stand, the stand’s diversity of species, and other factors, including the adaptive capacities of particular species.  The capacity of particular species to adapt to shifts in climatic circumstances is largely determined by the level of genetic variation within the species in that ecosystem, and by the rate at which such organisms reproduce. While particular species in Lebanon forest ecosystems (for example, bacteria) reproduce at rates that may allow them to “evolve with” changing climatic circumstances, other species (for example, trees) have slower reproductive cycles – a circumstance which likely leaves such organisms incapable of adapting to the climatic changes that are envisioned in the coming century in Lebanon. For these species, migration represents the second and more viable “option.” In spaces where changed weather patterns inhibit the survival of particular organisms, those organisms will die; however, the species (for example, Cedar or Juniper) may continue to survive by “shifting” its location to microclimates that are more conducive to survival. For example, in the case of tree organisms in Lebanon adapted to cooler and wetter environments, the warming and drying of particular spaces will likely encourage those populations to “shift” northwards (latitudinally) or upwards (altitudinally). Yet, as with rates of adaptation, the rates of migration of many species presents an obstacle. The IPCC describes this dynamic, as it is occurring on a global scale: “Most plant species cannot naturally shift their geographical ranges sufficiently fast to keep up with current and high projected rates of climate change in most landscapes.” In Lebanon, it remains to be seen with what success populations will be able to move to new spaces that continue to have climatic conditions conducive to survival.

=Projections for Lebanon Forest Stands=

These are dynamics that will likely unfold within the cedar, juniper, oak, fir, and pine forest ecologies in the country. Researchers envision a number of specific patterns that global climate change may bring to Lebanon’s forest stands. The ratio of precipitation to temperature is expected to drop in all of the regions within which these stands exist as the century unfolds. Related, researchers envision a 5% – 15% increase in the prevalence of “Arid” bioclimatic levels within Lebanon. These climatic dynamics mean decreases in the levels of water available for these forest stands – both due to decreased precipitation and increased evaporation from higher temperatures. In turn, forest ecosystems may experience degradation of the overall structural integrity of their biotic (floral) components: decreased moisture availability will likely cause both inhibited growth and dieback among floral organisms, notably trees. Animals and insects that depend on the integrity of tree species for habitation or nourishment will in these circumstances face challenges. Researchers also project an increased risk of forest fire in many microclimates; while some tree species in fact show high adaptivity to such prospects, other species – such as Pinus Halepensis and Juniperus Exelsa—have shown notable vulnerability to forest fire. In addition, shifts in weather patterns has the potential to engender shifts in the population dynamics of various species that are implicated in the survival of other species. Increased temperatures may engender increased pest populations, fueling increased consumption and habitation of trees and degradation of forest stands; bioclimatic shifts may create changes in the levels and distributions of tree pollinating populations, inhibiting those tree species’ reproductive capacities; new ecosystemic circumstances from climatic changes may also create new niches for invasive species, who may then outcompete other species for ecosystem resources.

These are ecological dynamics that may emerge in Lebanon’s forest stands from climate change. Myriad other organismal and ecological potential implications of climate change also exist, including the influences of climate variability on plant phenology, genetic erosion from population fragmentation, pressures that temperature warming presents to the adaptive capacities of particular organisms, and other dynamics that will not be exhausted here. Importantly, certain forest types of Lebanon have been noted as particularly vulnerable.

Oak
Oak forest stands comprise about 42% of Lebanon’s forests – or, 61,000 ha. According to Researchers from Lebanon’s Ministry of Environment, in the face of the future effects of climate change, the resilience of these stands is “low,” and their vulnerability is “high”; researchers envision a “moderate decrease” in oak area and oak organism population density directly from effects of climate change. Decreases in precipitation and increases in temperature will likely encourage necessary migrations to higher altitudes – into spaces where climatic conditions may be more conducive to survival. The combination of this circumstance with the presence of a “limited” area into which oaks might migrate makes these types of ecosystems particularly vulnerable.

Fir
The second stand type that has been marked as particularly vulnerable is the fir stand. The fir covers 1,600 hectares of Lebanon; this represents 1.2% of Lebanon’s forest land. Nonetheless, researchers highlight this ecosystem type as deserving of attention, due to various factors that make its resilience “low” and its vulnerability “high.” Given its present geography and the traits of fir trees, projected decreases in precipitation and increases in temperatures will likely encourage northward migration. This pressure, along with levels of forest fragmentation among fir stands, contribute to the vulnerabilty of this ecosystem type in the face of climate change. Researchers in turn envision a “moderate decrease” in the population densities and the number of mature individuals in fir stands; yet, researchers also envision a “high decrease” in population density and number of mature individuals if climatic changes occur at the same time as high levels of human development.

Juniper
The Juniper tree and ecosystems containing many Juniper trees have been noted as particularly vulnerable: the resilience of these ecosystems is “low,” and researchers have characterized their vunerability as “very high.” Similar to fir trees ecosystems, Juniper tree ecosystems are expected to experience a “moderate decrease” in population density, and also in regeneration rate, directly from climatic factors, but a “high decrease” when climatic factors are combined with high levels of human development. Notably, decreases in precipitation and increases in temperatures may engender a shift in the typical Juniper microclimate from “Sub-Humid” to “Semi-Arid”: this is a circumstance that would impair the capacity of Juniper trees for regeneration. By 2080, climatic changes could erase the presence of the “Oromeditteranean Region,” which is a principal bioclimatic region for Juniper stands in Lebanon. Presently, Junipers cover 11,000 ha of Lebanon’s land. This is an area of coverage that has declined significantly from 1965, and that may indeed continue to decline from the combined effects of climate change and human pressures as the century unfolds.

These are fates for these forest stands that may come from the particular broad reasons noted, in combination with other myriad effects that shifting patterns of climate may have on particular forest ecologies.

=The Cedar= Cedar stands in Lebanon also face challenges from the potential effects of future climate change. Cedars in Lebanon have had a significant place in both the popular consciousness and the economies of inhabitants of this land. The role of Cedar wood in local economies historically has resulted in degradation and depletion of Cedar stands, over time; extraction of wood from Cedar trees has resulted in, as Fady et. al (2008) describe it, “Millenia-long extensive deforestation.” The combination of these patterns of human extractions and other (anthropogenic, climatic, environmental) pressures has resulted in a significant reduction in the salience of Cedar trees and Cedar forest ecologies within Lebanon territory: from an abundant and “continuous” forest covering 500,000 ha in the post-glacial period, to stands today that are much more fragmented, and that cover only 2,000 ha of Lebanon, comprising 1.6% of its forest area. Today, there are around 12 “identified” Cedar forest stands in Lebanon; these include the Cedars of Tannourine, the Cedars of Hadeth, the Barouk Cedars, the Maaser Cedars, the Cedars of Niha, and other stands, found on Mount Lebanon and elsewhere. These ecosystems frequently exist in bioclimatic regions with higher levels of humidity, with mild to cool winters, with annual levels of precipitation in between 1300-1500 mm, and also at relatively high elevations, from 1100 – 1950 M. These are ecosystems characterized by their presence of Cedar trees, but that also are habitats for a variety of other species. Researchers note: “These forests are currently shelters for high diversity… and harbor a range of endemic plant species.” Talhouk et. al (2005) similarly describe how “Lebanese Cedar forests harbor a range of plant species estimated as varying between 500 (Tohme et. al 1999) and 1030 (Semaan and Haber 1998) and varying numbers of endemic plant species; 49 in Ehden and 61 in Al-shouf reserve.”

Similar to the other forest stands discussed above, these ecosystems, and the Cedars themselves, have evolved in interaction with climatic conditions over time. Their present capacities for survival in climatological conditions (mentioned above) can be understood as contingent upon these historical adaptations. The physiologies of Cedar trees in Lebanon today represent traits that have been selected for over time, as the Cedrus libani species has interacted with its environment; climatic conditions have represented part of this “environment,” “shaping” the ways in which Cedars in Lebanon have evolved, and engendering adapted physiologies which allow them to flourish in particular climatic conditions today. In addition, Cedars have shown particular patterns of response to past climatic conditions in Lebanon: as Hajar et. al (2010) note, Cedars in Lebanon historically were more abundant in the Bolling/Allerod paleobotanical period – in which conditions were generally wetter and cooler – and showed decreased abundance during the Holocene period, which exhibited higher temperatures. These patterns of evolution and historical fluctuations in population abundance collectively point to this: Cedar trees have evolved in ways that enable them to better survive in certain climatic conditions as compared to others – and changes in climatic conditions can significantly influence the capacity of the Cedar to survive and flourish. In fact, Hajar et. al (2010) argue that present distributions of Cedar stands can be hypothesized or charted mainly by attention to the various climatic variables in regions of Lebanon. Climatic variables have everything to do with the capacities of Lebanon Cedars and Cedar stands to flourish – a reality supported by attention to their evolved physiologies and to their historically fluctuating abundances in varying climatic conditions. The Lebanon Ministry of Environment characterizes the resilience of Cedar forest stands to climate change as “low,” and characterizes their overall vulnerability as “high.” Other researchers express similar concern over the capacity of Cedar stands in Lebanon to flourish with the types of climatic shifts envisioned in the country (Hajar 2010; Sattout 2008; Fady 2008). These concerns stem largely from awareness of the threats that shifting bioclimatic levels represent to the present microclimates to which Cedars are adapted. As regions where Cedars in Lebanon presently flourish become both warmer and drier, Cedar trees will likely experience more difficulty surviving in those microclimates; this warming and drying can be correlated to an “upward shift in bioclimatic zones,” wherein cooler and wetter spaces “shift” upward (altitudinally) as warming occurs. With these climatological shifts, and as other researchers predict, Cedar stands will be forced to move upwards, to higher altitudes, in order to exist in spaces with climates conducive to survival. Importantly, this upward movement represents a possibility in some present Cedar stands, and an impossibility in others. Hajar et al (2010) describe: “Today, in Lebanon, most of C. Libani forests cannot expand any higher because they are already located at the summit of mountains. Only Bcharre, Ehden, and Tannourine have higher altitudes.” These necessary forms of future migration will also be made more difficult by human development: human presence and development around Cedar stands and spaces of potential migration can inhibit the processes necessary for migration. Researchers in turn envision this reality: “Only a few of the existing C. Libani forests will be able to survive in the Northern part of Mount Lebanon.” While the extent of future Cedar stand degradation and fragmentation from climate change is neither totally clear, nor projected to be uniform across Lebanon, Cedar trees – and the ecosystems of which they are apart – do face challenges from these projected shifts in bioclimatic levels, the limited availability of space for the necessary migration, human developments that impede these migrations, and also various other ecological implications of shifting weather patterns. Some of these ecological implications within Cedar ecosystems will be explored in greater detail below.

Water Availability and Cedar Development
A principal factor generating the types of geographic effects discussed above is the projected presence of water in future Cedar ecosystems: hypothesized levels of increased temperature and decreased precipitation will together likely result in decreased moisture availability in the ecologies where Cedars live. These decreased levels of moisture will likely interact with Cedars in myriad ways – the details of which researchers have explored. First, among Mediterranean Cedars, drought treatment has been shown to significantly impede biomass production: for Cedars receiving (50%) decreased water supplies for multiple one-two month periods, biomass production has been shown to decrease by an average of 62%. Specifically amongst Lebanon Cedars, these drought treatments engendered significant reductions in the rate of growth of both tree diameter and tree height; researchers imagine that drought circumstances in native ecosystems would fuel similar mitigations to organism development. Beyond biomass reduction, drought appears to create a number of correlated implications for the bodies of Cedar trees. Decreased biomass production from drought appears to decrease the hydraulic conductivity of Cedar tree tissues, inhibiting their capacity to move water through xylem tissues to leaves (the sites of photosynthesis); decreased biomass production from drought also appears to decrease a Cedar’s water use efficiency – drought-induced patterns of morphological development hamper the efficiency with which these organisms use water; drought among Cedars also “reduce(s) shoot growth more than root growth,” as organisms develop more extensive root networks, and a greater proportion of the organism in turn exists underground. Fundamentally, for Lebanon Cedars, decreased availability of moisture in ecosystems inhibits the capacity of the plant to develop, which can have harmful implications for a number of other important plant processes. Furthermore, researchers have found that Lebanon Cedars are particularly drought sensitive, the “most sensitive to drought” as compared to Cedar trees that exist in Turkey. In comparison to these other genuses, Lebanon Cedars exhibited less extensive root systems in response to drought, lower hydraulic conductivities (in their leaves), and lower levels of biomass production. The particular physiological characteristics of Lebanon Cedars in turn make them vulnerable to the types of hydrological effects that may come with global climate change in coming years. The vulnerability of these organisms to drought corresponds to a vulnerability of the ecosystems of which they are apart.

Pest Populations
Historically, pests have represented a significant challenge to both the health of individual Cedar organisms and to Cedar forest ecosystems in Lebanon. For example, pest outbreaks have engendered significant levels of degradation in the Cedar Tannourine Reserve – effects that have been mitigated by preservation efforts. Notably, The salience of tree pests at a large scale has been linked to climatic conditions: “During the last three decades, an expansion of the geographic range of major forest insect pests has been observed, caused by an increase in winter temperatures.” For the Lebanon Cedar, one insect in particular has created morphological desruction: this is the Cedar Web-Spinning Sawfly, or Cephalcia tannourinensis. The potential impact of this insect on Cedar trees and ecosystems may increase with the projected effects of climate change. This possibility is due to the interaction between temperature and moisture, and the sawfly’s reproductive cycle: researchers have shown that both increased temperatures and decreased levels of soil humidity appear to increase the rates of reproduction of Cephalcia tannourinensis. Increased rates of reproduction of the sawfly have engendered increased levels of degradation in Cedar ecosystems in Lebanon, because more pests leads to more tree destruction; in turn, the warming and decreased levels of soil moisture that are projected for Lebanon may indeed exacerbate the effects of these pests on Cedar stands. As Sattout and Nemer (2008) write: “Based on the projections for climate change in the next decades, it is highly likely that C. tannourinensis and other organisms with distributions determined in part by temperature, will continue expanding their geographic range and causing outbreaks.” This is an insect that has and will likely continue to represent a significant threat to the integrity of Cedar forest ecosystems, particularly with the effects of climate change.

Population Genetics
Climate change in Lebanon also has the capacity to impact the genetic makeup of Lebanon’s Cedar populations – an effect that will impact the capacity of the species to survive and flourish into the future. The potential impact of climatic changes on Cedrus libani genetic diversity stems from the fragmentations that these changes may create among Cedar stands in the coming years. Increased levels of fragmentation – for example, more frequent population discontinuities and larger spatial gaps between populations -- tends to increase the genetic differentiation of organisms across those populations, and decrease the level of genetic diversity among the organisms that belong to one particular community. Geographic distance between two populations tends to decrease the intraspecies genetic diversity within those populations, because less gene flow occurs across those populations. In the case of Lebanon Cedar stands, these forms of fragmentation do have the capacity to decrease intrapopulation diversity in this way; or, “Fragmentation of cedar forests has occurred over a long enough time that its effects should have been registered in patterns of genetic structure and diversity.”  Different researchers have different views on the effects of these fragmentations on the present genetic diversities of Lebanon Cedars. Semaan and Dodd (2008) locate high levels of genetic diversity within Cedar populations and low levels of differentiation across Cedar populations, which represents a sign of Cedar population health. In contrast, Fady et. al (2008) notice lower levels of genetic diversity, and relatively high levels of differentiation across cedar populations. These researchers found “low gene flow, high differentiation, and severe cases of genetic drift (among Cedars in) in Lebanon,” a circumstance that leads them to the conclusion that, “In Lebanon, most populations are currently under threat, either because of low gene diversity, small size or low natural regeneration.” For these researchers, these low levels of (intrapopulation) Cedar genetic diversity can be explained by historical human impact on Cedar stands, which, they theorize, engendered fragmentation and genetic homogenization. Regardless of present genetic diversities, these studies reveal a reality in relation to the future of Lebanon Cedar genetic makeup: increased levels of Cedar forest fragmentation that emerges from changing climatic conditions may likely, based on theory and on history, decrease the intrapopulation genetic diversities of Lebanon’s Cedar trees. Decreased levels of genetic diversity within such populations will in turn inhibit their capacities for survival in the face of environmental stresses; if more Cedars emerge with more similar DNA over time, more of them will die off in the face of particular environmental circumstances that are commonly challenging, and fewer in the species will survive and reproduce. Further, these possibilities of genetic homogeneity – potentially contributed to by climate change -- may make Cedar stands particularly vulnerable as new and potentially stressful climatic conditions visit Lebanon’s microclimates. In these ways, climatic changes in Lebanon may fuel decreases in genetic diversity amongst Lebanon Cedars, and may also present new environmental stresses that a less-diverse Cedar population finds harder to withstand.

These are ecological dynamics that future effects of climate change may indeed catalyze. These effects may interact with other ecological dynamics created by shifting climatic conditions in Lebanon Cedar stands. Collectively, projected climatic changes do appear to represent significant threats to the integrity of these forest ecologies.

=Implications for Lebanon’s (Human) Population=

Cultural Consciousness
Lebanon’s Cedar trees – historically and contemporarily – have had a significant place in the cultural consciousness of inhabitants of Lebanon land. For long periods of time, the prominent role of the Cedar in the economies of historical civilizations positioned the Cedar as a significant symbol in the economic fabrics and collective consciousnesses of those societies. The Lebanon Cedar is on the Lebanon flag; this circumstance symbolizes the Cedar’s place in a nationalist collective consciousness, envisioned and embodied by different Lebanese actors over the course of the 20th century involved in forms of Lebanese nationalism. And, the Cedar still does hold import to Lebanese individuals today: according to one study, three-quarters of (323) individuals said that they would be willing to invest money toward projects for the conservation of Cedar stands. Despite the fact that it only comprises 1.6% of Lebanon’s forests, the Lebanon Cedar has held and still does hold cultural significance in Lebanon; in this way, the potential effects of climate change on these organisms carries particular cultural weight.

Forest Economy
Forests in Lebanon do play a role in local economies. In 2001, the economic value provided by forests in Lebanon was $130 Million. Beyond this figure, forest ecologies offer a number of resources that are integrated by particular communities into modes of survival. Rural communities in Lebanon burn tree wood or produce charcoal from tree wood to enable cooking and heating; aromatic and medicinal parts of plants are extracted from forests and utilized by various rural communities; individuals extract nuts from pine trees and carob pods from carob trees, and then eat, sell, or process those foods; various individuals and communities keep bees, and then sell the honey that the bees produce; individuals, groups, and companies also gain capital from forms of ecotourism that are enabled by Lebanon’s forest ecosystems, and the beauty that they offer. Importantly, these forms of economy and modes of survival may be compromised, as climatic conditions affect forest ecosystems during the 21st century. The Upper Akkar Watershed represents one region in Lebanon where these economic implications of climate change become clear.

The Upper Akkar Watershed
One area in Lebanon where these dependencies on local natural resources is salient is the Upper Akkar Watershed; this is a region located in the north of Lebanon, with the coastal plains and the Mediterranean sea to the west, a mountain chain to the east, and Syria to the North. Many of the individuals who reside in this region of Lebanon live in rural communities; these are communities in which many forms of economy and modes of subsistence happen from dependencies on the land, and on the flows of materials and energy in the spaces where people live. Rather than relying on large-scale, international networks of trade, many individuals in these communities depend on local sources of water, local soil for agricultural production, and also local forests for resources; this is a region “characterized by a typical rural community that highly depends on natural resources.” 63% of families in this region live in poverty, and 73% live on less than $107 per month. The potential effects of climate change on individuals living in these communities is thus notable and significant, in comparison with other individuals who either live in cities, have higher amounts of capital, or have avenues of subsistence that exist outside of local ecosystems. The potential effects of climate change on local ecosystemic dynamics – both within forest ecosystems and in other ecosystems – can also have significant impacts on local modes of survival. In three Akkar villages that were surveyed by researchers – Qobayat, Andaket, and Aydamoun – recent climatic changes have already been witnessed, and have already impacted local economies. Surveyors found that individuals in these communities have been aware of, in recent years, decreases in crop productivities, decrease in levels of soil fertility, decreases in geographic areas that can be cultivated for farming, decreases in water availabilities, and increases in agricultural diseases. These are economic effects that have come from climatic patterns noticed by local residents, including an increase in summer temperatures, a decrease in overall levels of rainfall, a decrease in the number of rainy days, and an increased frequency of drought years in recent times. Additional climatic dynamics have also influenced the forests around these villages, notably catalyzing increased levels of pest outbreak and forest fires. Local modes of survival and social reproduction contingent on agricultural land – and also, to an extent, on forests – have already been affected in these villages by global climate change. One village in particular received particular attention: researchers have noted “the high vulnerability of Aydamoun village to climate change aspects…due to the fact that Aydamoun represents a typical rural community highly dependent on natural resources.”

The village of Aydamoun and the Akkar Watershed more broadly are indeed sites of a broader dynamic, in Lebanon and also around the planet: global climate change, engendered by historical and contemporary industrialization and energy consumption in certain spaces, has particular (unequal) effects on other spaces, in communities where humans depend on the resources, materials, and ecosystems being influenced by changes in climate. Activists for Climate Justice seek to respond to this (global) dynamic, both by decreasing levels of carbon emissions in places like Tripoli and Beirut, and increasing levels of community resilience in places like Qobayat and Aydamoun.

Climate Change and Lebanon
Effects of global climate change in Lebanon have already been witnessed, and will likely continue to be observed as the century unfolds. Changes in climatic conditions will (continue to) interact with forest ecosystems in this region, and the organisms within those ecosystems, in a variety of ways. Degradation of forest ecosystems in Lebanon have been significant in recent decades, and climate change will likely represent an additional source of pressure on these ecosystems, alongside other human pressures. Notably, climate change in Lebanon has also influenced -- and will likely continue to influence -- a variety of human communities, especially those that are particularly reliant on the materials and resources found in the ecosystems that surround them. Efforts toward both climate change mitigation and building resilience may represent important measures, for both human and non-human communities in Lebanon.