Leaf Area Index

The Leaf Area Index (LAI) is defined as the total area of one-sided leaves per ground surface area.    It is a fundamental property of the plant canopy as it plays a key role in the absorption of solar radiation, through photosynthesis, and thus on the vegetation growth. LAI can be estimated by ground measurements…

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FAPAR

The FAPAR is defined as the fraction of photosynthetically active radiation (400-700 nm) absorbed by the green vegetation (Fraction of Absorbed Photosynthetically Active Radiation). This variable expresses the energy absorption capacity of the vegetation and thus its growing capacity. FAPAR varies between 0 and 1. Canopy with a FAPAR of 1 totally absorbs the photosynthetically…

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Canopy Height

Canopy height is the height (in meters) of the top aboveground vegetation. Canopy height is an important structural variable as it directly influences a large number of processes. This variable is a major concern for agricultural, ecological and meteorological fields and their applications. For instance, canopy height has a direct impact on wind speed which…

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Canopy Cover

The canopy cover is defined as the fraction of ground covered by green vegetation. This variable represents the horizontal dimension of the vegetation and allows to quantify its spatial extent. Canopy cover is an essential variable as vegetation extent strongly influences the water, energy and matter fluxes of land surface. Canopy cover is notably very…

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lifeform

Vegetation life-form (growth form) classes are defined based on structural similarities of plants. Three main life-forms are encountered in the nature: woody, herbaceous and lichens/mosses forms. Identification of life-forms can be performed through human resources (see here). However, this is a long, expensive and fastidious task. Furthermore, all land surface areas are not necessarily accessible to…

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leaf type

There are many types of leaves. Leaf type is defined as the type of leaf morphology. It is mainly linked to the botanical group of plants (Angiosperm and Gymnosperm). The two main types of leaves are the broadleaves and the needle-leaves. Broadleaves is the most common type of leaves that can be encountered on flowering plants. Broadleaves…

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phenology

Phenology is the study of the timing of vegetation life-cycle events, such as budburst, flowering, leaf colouring, leaf fall, etc.. Change in plant phenology impacts the whole ecosystem functioning and productivity. For example, change in flowering impacts the timing and the intensity of the pollen season. Plant phenology can be studied from ground observation (see here)…

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Net Primary Productivity

Net Primary Production (NPP) is defined as the net amount of carbon uptake after subtracting plant respiration (plant CO2 release) from Gross Primary Product (plant CO2 uptake). NPP measures the mass of the new plant growth (fixed carbon) during a time period. NPP can be estimated by ground measurements (see here) or through satellite/airborne sensors Unit:  gC/m2/day Available products over…

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Gross Primary Productivity

Gross Primary Production (GPP) is defined as the amount of carbon uptake by plants per time unit through the photosynthesis process. GPP is an important variable as it partially supports plant respiration. GPP cannot be directly measured but can be estimated through meteorological towers (CO2 exchanges) (see here) or using satellite sensors. Unit:  gC/m2/day Available products over Greece:…

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Woody Biomass

Woody biomass is defined as the total mass of living plant material per woody area. Aboveground biomass plays a key role in the carbon cycle and climate processes. It can be measured through direct or indirect in situ sampling (see here) or estimated through satellite/airborne sensors. Typically, biomass in woody areas ranges between 0 (poorly vegetated…

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Plant Species

Plant species are defined as categories of plants which show common attributes and which are called by a common name. Presence/absence of plant species is very important for diverse fields such as ecology, forestry and agriculture. Indeed, plant species diversity is important for maintaining genetic diversity and wildlife habitats, limiting diseases propagation, and regulating a…

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Crop Type

The crop type is the type of plants cultivated in the fields during the main growing season. The crop type can be, for example, maize, potatoes, etc. The type of crops is important for various applications such as hydrological modelling, plant health, crop science, environment monitoring, biodiversity safeguard, etc. Indeed, the type of plants directly…

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Vegetation Moisture

Vegetation moisture, also called vegetation water content, is defined as the quantity or ratio of water within the canopy. This is the difference between the fresh and dry matter weight. Vegetation water content is an important variable as it reflects vegetation health. Water is a limiting component in various biogeochemical processes, such as photosynthesis, evaporation…

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Foliar Chemistry

Foliar chemistry represents the chemical content within the leaves of canopy. Chemical molecules can be chlorophyll, carotenoid, nitrogen, etc. Change in chemical content may change with vegetation phenology and health. It can be directly measured through destructive methods or indirectly estimated from ground/airborne/satellite-based remote sensing (see here for ground measurements). Whereas direct measurements of chemical content are…

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Burnt Area

Burnt area products map the areas affected by fires and give temporal information on the fire events. Whereas fires are part of natural processes, they can also lead to environment disturbances. Indeed, fires are a major factor in land covers change as they affect the whole environment, including soil, water, air, wildlife, etc. For example,…

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Herbaceous Biomass

Herbaceous biomass is defined as the total mass of living plants, that have a non-woody stem, per area. Aboveground biomass plays a key role in the carbon cycle and climate processes and is of major importance in various field such as agronomy, biodiversity, climate, energy production, etc. Herbaceous biomass can be measured through destructive or…

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Canopy Layers

Vegetated areas are composed of a top canopy layer. However, they also have a vertical structure and different understory vegetated layers/strata can be encountered. The understory is composed of a shrub layer, a field layer (ferns, herbaceous and graminoids) and a ground layer (mosses and lichens). However, vertical structure of vegetation differs from an area…

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Non Photosynthetic Vegetation

Non-Photosynthetic Vegetation (NPV) is defined as the vegetation cover which does not take part into photosynthesis process. It is composed of the dormant, senescent or dead vegetation, as well as the woody parts of plants (trunks, stems and branches). Most of the time NPV is located under a photosynthetic canopy. Because NPV has an impact…

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