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Specific leaf area

Specific leaf area (SLA) is a key plant functional trait defined as the ratio of the one-sided area of a fresh leaf to its oven-dry mass, typically expressed in units of square meters per kilogram (m² kg⁻¹).^[1] It serves as an inverse measure of leaf mass per area (LMA) and indicates leaf thickness and density, reflecting the biomass invested per unit of photosynthetic surface.^[2] Higher SLA values correspond to thinner, lighter leaves that facilitate greater light capture and nutrient turnover, while lower values denote thicker, denser leaves with higher construction costs.^[3] SLA forms a central axis of the worldwide leaf economics spectrum (LES), a coordinated set of traits observed across over 2,500 species and 175 sites globally, linking leaf structure to physiological performance.^[2] In this spectrum, SLA positively correlates with net photosynthetic capacity per mass, leaf nitrogen and phosphorus concentrations, and dark respiration rates, while negatively correlating with leaf lifespan and LMA.^[2] Plants with high SLA adopt a "fast-return" strategy, prioritizing rapid growth and resource acquisition in resource-rich environments, whereas low-SLA species employ a "slow-return" approach, enhancing leaf durability and longevity in stressful conditions.^[2] These relationships hold broadly across growth forms, functional types, and biomes, with only subtle modulation by climate factors like mean annual temperature and precipitation.^[2] Ecologically, SLA influences plant growth strategies, competitive interactions, and responses to environmental gradients such as drought, nutrient availability, and light levels.^[3] It is a critical predictor of canopy structure, photosynthetic efficiency, and whole-plant productivity, making it valuable for modeling ecosystem dynamics and biodiversity patterns.^[3] Standardized protocols for SLA measurement— involving fresh leaf area assessment via image analysis or meters, followed by oven-drying at 60–80°C to constant mass—ensure data comparability in research.^[1] Global datasets reveal SLA typically ranges from 2 to 50 m² kg⁻¹, varying phylogenetically and with habitat, underscoring its role in understanding plant adaptation and climate change impacts.^[4]

Definition and Fundamentals

Definition and Units

Specific leaf area (SLA) is defined as the one-sided area of a fresh leaf divided by its oven-dry mass, quantifying the light-capturing surface area supported per unit investment in dry biomass.^[5] This trait reflects the balance between leaf expansion for resource acquisition and the structural costs of tissue construction. The core formula is SLA = A / M, where A is the total one-sided leaf area (typically measured in m²) and M is the oven-dry leaf mass (in kg).^[5] The standard unit for SLA is m²/kg, though mm²/mg is equivalently used in practice due to numerical identity (1 m²/kg = 1 mm²/mg).^[5] For instance, an SLA value of 20 m²/kg means that 1 kg of dry leaf mass corresponds to 20 m² of projected leaf area, illustrating the trait's role in scaling leaf function to biomass allocation.^[5] Values typically range from less than 1 m²/kg in thick, dense leaves to over 300 m²/kg in thin, expansive ones, though specific measurements depend on species and conditions.^[5] The inverse of SLA is leaf mass per area (LMA), calculated as LMA = M / A and expressed in g/m² (or equivalently kg/m²).^[6] LMA provides a complementary perspective on leaf construction, emphasizing mass investment per unit area rather than area per mass. It decomposes into the product of leaf thickness (LTh, often in μm) and leaf density (LD, in g/cm³), via LMA = LTh × LD (with unit conversions to achieve g/m²), highlighting how anatomical features like tissue layering and cellular packing contribute to overall leaf economics.^[6] The concept of specific leaf area originated in early 20th-century plant physiology, with foundational studies before the 1990s exploring leaf efficiency and growth analysis through metrics like area-to-mass ratios.^[7] It gained formal prominence in modern ecology around 2000, particularly through Westoby et al. (2002), who integrated SLA into global datasets of leaf traits to elucidate interspecific variation in plant strategies.^[7]

Measurement Methods

The standard protocol for measuring specific leaf area (SLA) involves harvesting fully expanded, healthy leaves from mature, unshaded plants, typically selecting sun-exposed leaves from the outer canopy for woody species to represent typical conditions.^[5] Fresh leaf area is measured immediately after collection using a flatbed scanner or digital image analysis software such as ImageJ, ensuring leaves are laid flat without overlap or curling; alternative low-tech options include grid paper overlay or planimeters for smaller samples.^[5] Leaves are then oven-dried at 60–80°C for 48–72 hours until reaching constant mass, after which SLA is calculated as the ratio of one-sided fresh leaf area to dry mass.^[5] To ensure comparability, standardization includes rehydrating wilted leaves by submerging them in water for several hours (typically 4–6 hours) prior to area measurement to minimize shrinkage errors, which can reach up to 20% or more if unaddressed.^[5] Sampling should occur during the peak growing season under consistent environmental conditions, with midday collection recommended to avoid diurnal variations in leaf water content; at least 10–20 fully expanded leaves per individual from 5–30 individuals per species are advised for robust statistical power, prioritizing multiple positions on the plant to capture intra-individual variation.^[5] Alternative methods include non-destructive volumetric approaches, where SLA is approximated by dividing estimated leaf volume (measured via water displacement or 3D scanning) by average leaf thickness obtained with digital calipers, useful for intact plants but requiring calibration against destructive samples for accuracy.^[8] Gravimetric techniques for bulk samples estimate SLA by correlating total dry mass of harvested leaf litter or fragments with area measured post-rehydration, suitable for large-scale or forest inventory studies where individual leaf processing is impractical.^[9] Historically, measurements evolved from manual tracing on paper with planimeters in the pre-1980s era, which were labor-intensive and prone to tracing errors, to post-2000 digital imaging via scanners and automated software, enabling higher throughput and precision.^[10] Key error sources include variability from leaf age (younger leaves often have higher SLA), position on the plant (shade leaves differ from sun leaves), and species-specific morphology such as vein prominence or petiole inclusion, which can bias area estimates if not standardized.^[5] Corrections involve excluding damaged or immature leaves, consistently including or excluding petioles and major veins per protocol, and using desiccators post-drying to prevent moisture reabsorption; global standardization protocols, such as those outlined by Pérez-Harguindeguy et al. (2013), recommend documenting these factors to facilitate cross-study comparisons.^[5]

Ecological and Physiological Significance

Rationale in Plant Ecology

Specific leaf area (SLA) serves as a fundamental proxy for the leaf economic strategy in plants, encapsulating the trade-off between the cost of leaf construction and the return on investment through photosynthesis and resource acquisition. High SLA values indicate leaves that are thin and lightweight, representing a strategy of low construction cost and rapid turnover, which facilitates quick carbon gain and growth in environments with ample resources like light and nutrients. Conversely, low SLA corresponds to thicker, denser leaves with higher construction costs but greater longevity and resource conservation, suited to stressful or resource-poor conditions where slow returns on investment enhance survival. This spectrum reflects an adaptive optimization of leaf economics, where plants balance immediate productivity against durability.^[11] The link between SLA and plant fitness is particularly evident in its positive correlation with relative growth rate (RGR), as higher SLA increases the leaf area per unit biomass, thereby enhancing light capture and photosynthetic efficiency relative to the investment in leaf tissue.^[12] This relationship underscores SLA's role in driving whole-plant growth dynamics, with meta-analyses confirming that interspecific variation in SLA explains a significant portion of RGR differences across herbaceous and woody species. From an evolutionary perspective, SLA embodies key trade-offs between rapid growth and defenses against herbivory or environmental stresses, as well as between short-lived acquisitive leaves and long-lived conservative ones. Global datasets, such as the Glopnet compilation from over 2,500 species across diverse biomes starting in the early 2000s, demonstrate SLA as a universal axis of variation, consistently coordinating with leaf lifespan and nutrient content to shape adaptive strategies.^[13] More recent efforts, including the TRY database with millions of trait records as of 2025, have expanded these insights, revealing SLA's responses to global change factors like elevated CO2, which can increase SLA and alter resource acquisition strategies.^[14] These patterns suggest that SLA has evolved as a core functional trait under natural selection, optimizing fitness in varying selective pressures. In broader ecological contexts, SLA integrates into theories of community assembly by influencing competitive interactions and species coexistence, where high-SLA species often exhibit superior competitive ability in productive habitats through faster resource exploitation.^[15] Similarly, SLA predicts invasion success, with acquisitive (high-SLA) strategies conferring advantages to exotic species in disturbed or nutrient-rich ecosystems by enabling rapid establishment and dominance over native flora.^[16] This predictive power positions SLA as a cornerstone for understanding trait-mediated ecosystem dynamics and biodiversity patterns.^[17]

Relationship to Other Leaf Traits

Specific leaf area (SLA) forms a core component of the leaf economics spectrum (LES), a globally consistent coordination of leaf traits that delineates strategies from rapid resource acquisition to conservative longevity. Within the LES, SLA covaries positively with mass-based maximum net photosynthetic rate (A_mass) (r² = 0.50, based on 764 species) and leaf nitrogen concentration (N_mass) (r² = 0.57), enabling high SLA leaves to support elevated carbon gain through greater nutrient investment per unit area, while exhibiting shorter leaf lifespans (negative correlation with lifespan, r² = 0.42).^[2] Conversely, low SLA leaves, characterized by prolonged lifespans, prioritize durability over quick returns on investment.^[2] This spectrum operates independently of plant growth form, functional type, and biome, with the principal axis capturing 74% of trait variation across a dataset of 2,548 species.^[2] SLA exhibits strong inverse relationships with other structural traits, notably leaf mass per area (LMA), which is mathematically its reciprocal and reflects leaf density and thickness.^[18] Similarly, SLA correlates negatively with leaf dry matter content (LDMC) (r = -0.52), indicating that leaves with high SLA tend to have lower dry matter density and higher water content, facilitating faster growth but reduced mechanical strength.^[19] Trade-offs arise with traits supporting mechanical support, such as higher venation density and sclerenchyma thickness, which increase in low SLA leaves to enhance structural integrity at the cost of reduced area per mass; for instance, SLA decreases with thicker sclerenchyma layers in drought-adapted species.^[20]^[21] At the anatomical level, SLA influences internal leaf structure, particularly the organization of palisade and spongy mesophyll, which governs light interception and CO₂ diffusion. High SLA leaves often feature a higher proportion of palisade mesophyll for efficient light capture within thinner blades, while low SLA leaves have more layered mesophyll and denser cell packing that limits internal airspace, reducing mesophyll conductance to CO₂ (positive correlation between SLA and conductance).^[22] These structural covariations contribute to the LES by linking SLA to physiological performance, with meta-analyses confirming that SLA, alongside LMA and related traits, accounts for 30-50% of variation in global leaf trait datasets through coordinated syndromes of adaptation.^[2]^[18]

Variation Across Plants and Environments

Typical Ranges and Patterns

Specific leaf area (SLA) exhibits a broad global range across vascular plants, from approximately 0.5 to 350 m²/kg (with most species between 3 and 33 m²/kg), reflecting diverse adaptations to resource availability and environmental conditions. This variation is documented in large-scale trait databases, with extremes observed in specialized groups: aquatic plants, particularly submerged species, show elevated SLA values exceeding 300 m²/kg (e.g., >333 m²/kg in Myriophyllum) to maximize light capture in low-light aquatic environments, while succulents display low values of <0.5 to 12 m²/kg associated with thick, water-storing tissues that reduce surface area per unit mass. Temperate trees generally fall within 10 to 30 m²/kg, balancing carbon gain and defense, whereas tropical evergreen trees tend toward 15 to 25 m²/kg, supporting persistent foliage in humid, resource-variable settings.^[18]^[23]^[4] Patterns of SLA variation are pronounced across plant life forms, with herbaceous species exhibiting higher values (20 to 100 m²/kg) compared to woody plants (5 to 50 m²/kg), enabling faster resource acquisition in short-lived or competitive growth strategies. Among major plant groups, angiosperms typically display higher SLA than gymnosperms; for instance, conifers (a key gymnosperm group) have low SLA averaging 5 to 15 m²/kg, linked to their needle-like leaves and longevity-focused economics. These life-form differences are evident in global trait compilations, where forbs and graminoids often exceed 20 m²/kg, while shrubs and trees average below 15 m²/kg for evergreen forms.^[23]^[24] Phylogenetic trends further structure SLA patterns, with evolutionary conservatism observed within families and clades, though broader differences emerge between major lineages such as monocots and eudicots. Monocots, including many grasses, often show moderately high SLA (around 20 m²/kg) suited to rapid growth in open habitats, while eudicots exhibit wider intraspecific and interspecific variability. Within families like Fabaceae, fast-growing species tend toward high SLA (e.g., 20 to 30 m²/kg or more), reflecting acquisitive strategies enhanced by nitrogen-fixing symbioses. These phylogenetic signals indicate that SLA is moderately conserved at family levels but diverges across deeper nodes, influencing global trait distributions.^[25]^[26]^[27] Comprehensive data on these ranges and patterns derive primarily from the TRY Plant Trait Database, initiated in 2007, which as of 2011 aggregated over 87,000 SLA measurements from more than 8,700 species worldwide, providing species-level means and highlighting intraspecific variation accounting for approximately 20 to 50% of total SLA variability across populations and environments. The database has since expanded substantially, with over 15 million total trait records across more than 305,000 plant taxa as of October 2022, improving coverage for SLA analyses. This database underscores global patterns, such as latitudinal gradients where SLA increases toward the equator for many functional types, while emphasizing the role of phylogenetic clustering in constraining trait values within lineages.^[23]^[28]

Influences of Environmental Factors

Specific leaf area (SLA) exhibits considerable phenotypic plasticity in response to varying environmental conditions, allowing plants to acclimate by adjusting leaf thickness and density to optimize resource capture and use. This plasticity is evident across gradients of light, nutrients, temperature, and soil moisture, where changes in SLA can alter leaf economics and photosynthetic efficiency without necessarily involving stress responses. Field and experimental studies demonstrate that such environmental influences account for substantial intraspecific variation in SLA, often 30-60% within habitats, complementing the typical ranges observed across plant species.^[18] Light availability profoundly affects SLA through shade acclimation, where plants in low-light environments produce leaves with higher SLA to maximize photon interception. In shaded conditions, SLA can increase by up to twofold compared to sun-exposed leaves, primarily via expansion of the mesophyll layer and reduced cell wall thickness, enhancing light capture per unit biomass. This response is particularly pronounced in shade-tolerant species, with phenotypic plasticity enabling rapid adjustments; for instance, seedlings under reduced irradiance show greener leaves and elevated SLA to maintain biomass production.^[18]^[29]^[30] Nutrient availability, particularly nitrogen and phosphorus, modulates SLA by influencing leaf construction costs and tissue density. Under enriched conditions, such as nitrogen fertilization, SLA typically increases by about 10-20% due to thinner leaves with lower dry matter content, facilitating greater leaf area expansion for enhanced nutrient uptake and photosynthesis, though responses vary by species (e.g., decreases in some trees). This effect is more evident in nutrient-poor soils transitioning to moderate fertility, where phosphorus addition similarly promotes higher SLA by reducing leaf density; however, severe limitations reverse this trend, leading to denser leaves.^[18]^[31]^[32] Temperature and elevation gradients drive SLA reductions in cooler environments, promoting denser leaf structures for thermal protection and efficient resource use. At higher altitudes, where temperatures decline, SLA can decrease by 10-40% in alpine species, correlating with increased leaf dry matter content to withstand lower growing-season warmth. This pattern holds across populations and communities, with intraspecific variation primarily reflecting shifts in species composition along elevational gradients, though individual acclimation contributes through thicker palisade layers.^[18]^[33]^[34] Non-drought soil moisture levels and ontogenetic development further influence SLA, with moderate hydration enhancing leaf expansion. Optimal soil moisture supports higher SLA by promoting cell turgor and mesophyll development, contrasting with drier but non-stressed conditions that slightly compact leaves. During ontogeny, juvenile leaves often display elevated SLA—up to 30% higher than mature ones—reflecting investment in rapid growth phases before transitioning to denser adult foliage for longevity.^[18]^[35]^[36] Meta-analyses and field experiments, such as those synthesizing data from diverse herbaceous and woody species, confirm that these environmental factors collectively explain 30-60% of SLA variation through plasticity, underscoring their role in plant adaptation across ecosystems.^[18]^[15]

Responses to Stress

Response to Drought

Under water deficit, specific leaf area (SLA) typically decreases in plants as a key acclimation response to conserve water and prolong leaf lifespan, with reductions often around 20-30% in various species.^[37] This reduction occurs primarily through limited cell expansion in the mesophyll and increased leaf thickness, resulting in denser tissue that lowers transpiration rates while maintaining structural integrity. For instance, in the drought-tolerant shrub Atriplex canescens, heavy drought reduced SLA by approximately 25% during flowering and seed stages compared to well-watered conditions, reflecting a shift toward a more conservative resource use strategy.^[38] The underlying mechanisms involve osmotic adjustment, where plants accumulate solutes to sustain turgor and promote denser mesophyll packing, alongside hormonal regulation by abscisic acid (ABA), which induces stomatal closure and leaf rolling to minimize water loss. ABA signaling also coordinates cell wall modifications and reduced leaf expansion, enhancing drought tolerance without immediate tissue damage. These adjustments are evident across various species; in temperate grasslands, xerophytic grasses like Stipa exhibit SLA declines correlated with increasing aridity, adapting via needle-like leaf rolling to further reduce exposed surface area.^[39]^[40]^[32] Species-specific variations highlight the role of hydraulic strategies in SLA responses. Isohydric species, which tightly regulate leaf water potential through early stomatal closure (e.g., birch), often show SLA increases during post-drought recovery to restore photosynthetic capacity, while anisohydric species like poplar maintain higher conductance longer, leading to initial SLA stability or slight increases followed by sharper declines under prolonged stress. In Mediterranean shrubs, such as those in sclerophyllous communities, SLA drops by 20-30% under seasonal drought, coupled with higher leaf density and dry matter content to support survival in water-limited environments.^[41]^[42] Long-term chronic drought influences SLA across generations via maternal effects, where offspring of stressed parents develop lower SLA to enhance drought resilience, as demonstrated in 2010s global change manipulation experiments simulating prolonged water deficits. These transgenerational shifts, observed in herbaceous and woody species, involve epigenetic modifications and resource allocation changes that precondition progeny for arid conditions, reducing SLA by up to 15-20% under subsequent stress.^[43]^[44]

Responses to Other Abiotic Stresses

Specific leaf area (SLA) typically decreases under salinity stress in non-halophytic plants due to ion accumulation, which promotes thicker leaves and denser cuticles to limit water loss and ion uptake. In Centella asiatica, salinity levels of 100 mM NaCl reduced SLA by up to 35% compared to controls, correlating with decreased leaf expansion and increased leaf thickness.^[45] This response enhances leaf mass per area (LMA, the inverse of SLA), aiding osmotic adjustment but potentially limiting photosynthetic surface area. In contrast, halophytes exhibit a milder SLA reduction, with LMA increasing by only 14% under high salinity, often maintained through succulence that stores water and dilutes salt concentrations without proportionally thickening non-water tissues.^[18] Temperature extremes also induce SLA adjustments, generally lowering it under heat stress while increasing LMA during cold acclimation. Heat stress, such as simulated warming of +5.6°C in urban trees like Sophora japonica, reduces SLA by promoting denser leaf tissues and thinner palisade layers to mitigate protein denaturation and enhance heat dissipation, with reductions observed across multiple species.^[46] Conversely, cold acclimation in temperate plants like Poa species leads to thicker leaves with higher LMA (increases of 27-73% depending on leaf type), supporting frost resistance by minimizing ice nucleation sites and improving solute concentration for freezing tolerance.^[47] Air pollutants like ozone (O₃) and elevated atmospheric CO₂ represent additional abiotic pressures affecting SLA. Elevated O₃ exposure accelerates leaf senescence and reduces overall leaf area index in crops such as soybean (Glycine max), primarily through oxidative damage to mesophyll cells, though effects on SLA are inconsistent.^[48] Elevated CO₂, often studied in free-air CO₂ enrichment (FACE) experiments, typically decreases SLA by about 10% across woody and herbaceous species, as increased carbohydrate allocation thickens leaves and boosts LMA without proportional area expansion.^[49] Under combined abiotic stresses, SLA responses are often amplified, with interactions exacerbating reductions beyond individual effects. For instance, in arid ecosystems, severe warming (+3-5°C) coupled with drought stress decreased SLA by 15-25% more than drought alone in grasses like Clematis squarrosa, reflecting synergistic impacts on leaf hydraulics and carbon allocation.^[50] Recent FACE studies (as of 2023) indicate that elevated CO₂ can moderate SLA declines from concurrent O₃ or heat exposures in crops but does not fully offset them.^[51]

Applications

In Ecological and Biodiversity Studies

Specific leaf area (SLA) plays a pivotal role in community assembly by influencing niche partitioning and successional dynamics. In early successional stages, species with high SLA dominate due to their acquisitive resource strategy, which facilitates rapid growth and light capture in resource-rich environments following disturbances.^[52] This pattern reflects environmental filtering, where high-SLA species are favored in open habitats, while low-SLA species with tougher leaves prevail in later stages under increased competition and shading.^[52] Niche partitioning is evident as greater differences in SLA among neighboring species enhance survival and coexistence, stabilizing community structure through trait-mediated interactions.^[52] Functional diversity indices incorporating SLA provide insights into community structure and assembly processes. The convex hull volume metric, which quantifies the multidimensional trait space occupied by species, uses SLA alongside other traits to detect habitat filtering and assess the range of resource-use strategies within a community.^[53] Communities with broader SLA variation in convex hull volume indicate less filtering and greater potential for coexistence, as seen in diverse assemblages where SLA dispersion reflects adaptive differentiation to local conditions.^[53] In biodiversity-ecosystem function relationships, SLA contributes to productivity and stability by linking leaf economics to carbon and nutrient dynamics. Higher community-level SLA correlates with increased net primary productivity, as intraspecific SLA variation can drive up to fivefold gains in ecosystem carbon uptake in boreal systems.^[3] Meta-analyses and empirical studies further show that high-SLA communities exhibit greater temporal stability in productivity under varying conditions, owing to efficient resource acquisition.^[3] Additionally, high-SLA leaves decompose faster, accelerating nutrient cycling and supporting higher ecosystem functioning in grasslands and forests.^[32] SLA informs invasion ecology by revealing trait filtering in recipient communities. Exotic species often succeed when their SLA aligns closely with natives, facilitating integration without strong biotic resistance; in Mediterranean grasslands, colonizing exotics exhibit higher SLA than non-colonizers in resource-rich sites but converge under limitations, indicating habitat filtering.^[54] Case studies in California and Spanish grasslands demonstrate that SLA similarity reduces invasion barriers, with intermediates or acquisitive SLA values enabling exotics to exploit niches in disturbed or semi-arid environments.^[54] Global patterns of SLA reveal gradients across latitudes and biomes, aiding predictions of community shifts under land-use change. SLA generally increases with latitude, driven more by soil factors like pH and C:N than climate, with shrubs showing stronger patterns than trees or herbs.^[55] Biome-scale transects indicate higher SLA in wetter, temperate biomes compared to arid ones, reflecting adaptations to precipitation and temperature.^[55] Trait-based models using SLA project biome redistributions under land-use intensification, forecasting expansions of high-SLA tropical forests and contractions of low-SLA tundra, with up to 33% shifts by 2070 depending on emission scenarios.^[56]

In Agriculture, Forestry, and Remote Sensing

In agriculture, specific leaf area (SLA) serves as a key trait in crop breeding programs aimed at enhancing yield potential, particularly in cereals like wheat and maize. High SLA promotes rapid early-season growth and light interception, enabling better resource capture in resource-limited environments. For instance, breeding wheat varieties with elevated SLA has been shown to increase early vigor, leading to yield improvements under water-limited conditions by expanding ground cover and reducing soil evaporation.^[57] In maize, artificial selection for higher grain yield has resulted in modern hybrids exhibiting greater SLA in ear leaves compared to older varieties, which reduces respiratory costs per unit leaf area and supports higher net CO₂ assimilation during kernel set, contributing to sustained genetic gains in productivity.^[58] Additionally, SLA plasticity is targeted in developing drought-resistant cultivars, where adjustable SLA allows plants to balance growth and water conservation, as seen in trials optimizing SLA for stress tolerance without compromising overall biomass accumulation.^[59] In forestry, SLA informs timber quality assessment and plantation management strategies, particularly for long-rotation species where low SLA correlates with slower growth rates and higher wood density, desirable for structural timber. Species such as Douglas-fir and Norway spruce, common in managed plantations, exhibit SLA variations that influence crown architecture and photosynthetic efficiency, with lower SLA in mature foliage linked to enhanced stem wood properties like reduced knot size and improved compressive strength.^[60] This trait is integrated into process-based models for optimizing planting density and thinning regimes under projected climate scenarios, enabling forecasts of growth trajectories and timber yield while minimizing risks from pests or wind damage associated with overly vigorous, high-SLA growth.^[61] For example, in radiata pine plantations, monitoring SLA helps calibrate management to sustain leaf area index while adapting to changing precipitation patterns, ensuring long-term wood quality.^[62] Remote sensing applications leverage SLA for large-scale monitoring of canopy structure and function, often estimating it indirectly through correlations with vegetation indices like NDVI derived from hyperspectral or multispectral data. Hyperspectral sensors, combined with LiDAR, enable canopy-average SLA retrieval by inverting radiative transfer models that account for leaf optical properties, achieving accuracies suitable for ecosystem mapping.^[63] SLA is parameterized in global products such as MODIS-derived leaf area index (LAI) datasets, where it converts foliar biomass to area, supporting integrations into broader models for vegetation productivity assessment.^[64] In climate change modeling, SLA parameterization within dynamic global vegetation models (DGVMs) is crucial for simulating vegetation shifts, especially under increased drought frequency where lower SLA enhances water-use efficiency but may reduce overall productivity. Trait-based DGVMs like the Jena Diversity-DGVM incorporate SLA variations to predict community composition changes, with reductions in SLA signaling shifts toward drought-adapted, sclerophyllous species in aridifying regions.^[65] For instance, projections under RCP scenarios indicate that declining SLA in response to warmer, drier conditions could lead to reductions in LAI for temperate forests, altering carbon sequestration and biodiversity patterns.^[66] These models, validated against field traits, underscore SLA's role in forecasting ecosystem resilience, informing adaptive strategies in managed systems.^[67]

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[33]
Specific leaf area correlates with temperature: new evidence of trait ...
Aug 7, 2025 · We conclude that the variation in SLA along the temperature gradient comes primarily from changes in the relative abundances of species.
[34]
[PDF] Do Elevation and Aspect Predict Functional Trait Values in Alpine ...
Since temperature decreases with increasing elevation, we predicted that at high elevations plants would be shorter, narrower, and have smaller SLA values ( ...
[35]
Ontogenetic trait shifts: Seedlings display high trait variability during ...
Jul 30, 2021 · High water treatments had nearly fourfold higher soil moisture (t ... Some evidence suggests SLA responses to drought may also vary depending on ...Missing: non- | Show results with:non-
[36]
Changes in mass allocation play a more prominent role than ...
This intriguing difference indicated that the soil moisture status during later periods determined the state of SLA. Based on the discussion above, our ...
[37]
Effects of Drought Stress on Leaf Functional Traits and Biomass ...
Jul 22, 2024 · Under drought stress, the leaves became smaller but denser, the specific leaf area (SLA) decreased, but the dry matter content (LDMC) ...2. Results · 2.3. Biomass Allocation... · 3. Discussion<|control11|><|separator|>
[38]
General mechanisms of drought response and their application in ...
Leaf rolling is a common response of plants to water deficit, and it is a mechanism to reduce water consumption when water stress is present [57]. Leaf rolling ...
[39]
Rapid changes in leaf elongation, ABA and water status during the ...
The results of this study showed the possible role of ABA on growth resumption by the increase of relative water content and turgor via osmotic adjustment ...
[40]
Growth and physiological responses of isohydric and anisohydric ...
May 7, 2015 · Isohydric poplars have high water-use efficiency, while anisohydric poplars show faster growth under a variable water supply, with implications ...
[41]
Drivers of phenotypic variation and plasticity to drought in ...
Specifically, under drought conditions, plants produced more sclerophyllous leaves, with reduced leaf area and SLA, and higher leaf density and LDMC, which has ...
[42]
Transgenerational responses to climate change in Mediterranean ...
Transgenerational response to climate change varies with plant functional strategy. Acquisitive plant species are highly sensitive to warming and drought.Missing: chronic | Show results with:chronic
[43]
[PDF] Transgenerational legacy effects of drought in three ... - ULB : Dok
Under control conditions plants with maternal drought experience will show higher biomass, decreased SLA and higher LDMC compared to plants without maternal.
[44]
Unravelling the Morphological, Physiological, and Phytochemical ...
Dec 25, 2022 · In this study, specific leaf area decreased with an increase in salinity. Burslem et al. [30] showed that a higher leaf thickness is associated ...
[45]
Effect of simulated warming on leaf functional traits of urban ...
Apr 3, 2020 · For example, the specific leaf area decreases gradually with the increase of temperature, while the leaf dry matter content increases with the ...<|separator|>
[46]
Acclimation of photosynthesis and respiration is asynchronous in ...
Aug 10, 2007 · This form of acclimation includes physical changes to the leaves themselves; leaves developed in the cold tend to be thicker, with a higher leaf ...<|control11|><|separator|>
[47]
How does elevated CO2 or ozone affect the leaf‐area index of ...
Oct 12, 2005 · While an increase in LAI with elevated [CO2] is uncertain, decreased leaf area is a consistent feature of plants exposed to elevated [O3].
[48]
Coordination of leaf functional traits under climatic warming in an ...
Sep 14, 2022 · Responses to warming and warming-induced drought. Specific leaf area (SLA) decreased under more than moderate drought stress [49, 50], while ...
[49]
Trait-mediated assembly processes predict successional changes in ...
Early successional forests are typically dominated by species with acquisitive traits, such as low WSG and high specific leaf area (SLA), which enable rapid ...
[50]
A Trait-Based Test for Habitat Filtering: Convex Hull Volume - jstor
filtering are less well-developed. Here, we present convex hull volume, a construct from computational geometry, which provides an ?-dimensional measure of ...Missing: indices | Show results with:indices<|separator|>
[51]
Functional assembly of grassland plant species in native ...
Nov 3, 2022 · A major aim in invasion ecology is to understand the role of exotic species in plant communities. Whereas most studies have explored the ...
[52]
Soil and climatic drivers of plant SLA (specific leaf area)
SLA plays an important role in determining plants productivity, as changes in leaf SLA reflect changes to the structure and nutritional content of leaves.
[53]
Trait‐based projections of climate change effects on global biome ...
Nov 9, 2021 · We predicted the global distribution of plant community mean specific leaf area (SLA), height and wood density as a function of climate and soil ...Missing: latitudinal | Show results with:latitudinal
[54]
Modelling impact of early vigour on wheat yield in dryland regions
Mar 27, 2019 · The screening for increased vigour mainly includes the selection of larger embryo and greater specific leaf area progeny to increase the width ...
[55]
Artificial selection for grain yield has increased net CO2 exchange of ...
Modern hybrids showed increased ear leaf area per unit leaf dry matter (specific leaf area) ... Grain yield improvement of maize (Zea mays L.) hybrids in Ontario ...
[56]
Beat the stress: breeding for climate resilience in maize for the ...
Feb 16, 2021 · The mean grain yield improvement (genetic gain) of CIMMYT tropical maize ... specific leaf area of maize seedlings. Mol Breed 16:321–331. https ...<|separator|>
[57]
[PDF] Forest Growth and Timber Quality: Crown Models and Simulation ...
... forest growth and timber quality issues related to forest management. ... SPECIFIC LEAF AREA (SLA) IS AN IMPORTANT ecophysiological trait variable ...
[58]
A climate-sensitive forest model for assessing impacts of forest ...
... specific leaf area ( S L A , i m2 kg−1 DW) for the species as(4) ... timber quality and increases the risk of damage due to wind and pests. Delaying final ...
[59]
Leaf area and growth of Chilean radiata pine plantations after ...
Jul 9, 2018 · ... plantation management, including thinning on the relationships among ... Specific leaf area and leaf area index. Five trees were ...
[60]
[PDF] Estimation of Canopy-Average Surface-Specific Leaf Area Using ...
Specific leaf area (SLA) is an important ecological variable because of its links with plant ecophysiology and leaf biochemistry. Variations in SLA are ...Missing: definition | Show results with:definition<|control11|><|separator|>
[61]
An Overview of Global Leaf Area Index (LAI): Methods, Products ...
Apr 29, 2019 · Alternatively, leaf area can be calculated through the specific leaf area ... MODIS remote sensing estimates. Agricultural and Forest ...
[62]
Leaf area index estimation with MODIS reflectance time series and ...
Remote-sensing methods allowing the retrieval of LAI time series with ... specific leaf area (SLA), etc. (Laclau et al., 2009, Laclau et al., 2010 ...
[63]
A novel approach for modelling vegetation distributions and ... - Nature
Apr 7, 2016 · ... specific leaf area (SLA). LMA increased with increasing ... The Jena Diversity-Dynamic Global Vegetation Model (JeDi-DGVM): a ...
[64]
Trait-Based Climate Change Predictions of Vegetation Sensitivity ...
Jul 12, 2019 · We focused on three leaf traits, i.e., leaf area index (LAI), specific leaf area (SLA), and leaf nitrogen per unit area (Narea), which together ...
[65]
Next‐generation dynamic global vegetation models: learning from ...
Mar 15, 2013 · Seed bank model in a next-generation dynamic global vegetation model (DGVM). ... specific leaf area (SLA) and leaf longevity (Reich et al ...