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Dracaena Cinnabari
''Dracaena cinnabari'', the Socotra dragon tree or dragon blood tree, is a dragon tree native to the Socotra archipelago, part of Yemen, located in the Arabian Sea. It is named after the blood-like color of the red sap that the trees produce. It is considered the national tree of Yemen. A related tree of similar appearance, the drago, ''Dracaena draco'', grows in the Canary Islands, more than 7000 km from Socotra. Description The dragon blood tree has an upturned, densely packed crown. This evergreen species is named after its dark red resin, which is known as "dragon's blood". Unlike most monocot plants, ''Dracaena'' displays secondary growth, ''D. cinnabari'' even has growth zones resembling tree rings found in dicot tree species. Along with other arborescent ''Dracaena'' species it has a distinctive growth habit called "dracoid ". Its leaves are found only at the end of its youngest branches; its leaves are all shed every three or four years as new leaves simultan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diksam Plateau
The Diksam Plateau or Dixam Plateau () is a limestone plateau in Socotra, Yemen. The ''Firmihin forest'', located east of the ''Dirhur canyon'' within the plateau, has the highest concentration of Dracaena cinnabari, Dragon's Blood Trees on the entire island. Description The Diksam Plateau is an extensive area located near the geographic center of Socotra between the Hajhir Mountains and the southern coastal plain. Situated about 700 m above sea level, the plateau is home to herdsmen, named ''Bedouin'', who move from one site to another with their herds. They live in a high number of tiny villages scattered across the plateau, reflecting extensive pastoralism, on which their inhabitants are dependent. Wadi ''Dirhu'' or ''Daerh'' is a north–south running gorge dropping 700 m vertically from the plateau to the valley floor. The wadi is home of large stands of ''Adenium obesum'' and ''Dendrosicyos socotranus''. The largest and most extensive population of Dragon's Bloo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Onychognathus Frater
The Socotra starling (''Onychognathus frater'') is a species of starling in the family Sturnidae. It is endemic to Socotra island, which is off the southeast coast of Yemen. Its natural habitats are subtropical or tropical dry forest, subtropical or tropical moist lowland forest, subtropical or tropical dry shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally o ..., subtropical or tropical high-altitude shrubland, and rural gardens. The Socotra starling builds its nests in the hollow branches of Socotra's dragon blood tree (Dracaena cinnabari). In addition to feeding on grasshoppers and figs, the bird also eats the berries of the dragon blood tree and helps disperse the tree's seeds. References {{Taxonbar, from= Q1590308 Birds described in 1881 Endemic birds of Socotr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown (botany)
The crown of a plant is the total of an individual plant's aboveground parts, including stems, leaves, and reproductive structures. A plant community canopy consists of one or more plant crowns growing in a given area. The crown of a woody plant (tree, shrub, liana) is the branches, leaves, and reproductive structures extending from the trunk or main stems. Shapes of crowns are highly variable. The major types for trees are the excurrent branching habit resulting in conoid shapes and decurrent (deliquescent) branching habit, resulting in round shapes. Crowns are also characterized by their width, depth, surface area, volume, and density. Measurements of crowns are important in quantifying and qualifying plant health, growth stage, and efficiency. Major functions of the crown include light energy assimilation, carbon dioxide absorption and release of oxygen via photosynthesis, energy release by respiration, and movement of water to the atmosphere by transpiration. These f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vascular Tissue
Vascular tissue is a complex transporting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All the vascular tissues within a particular plant together constitute the vascular tissue system of that plant. The cells in vascular tissue are typically long and slender. Since the xylem and phloem function in the conduction of water, minerals, and nutrients throughout the plant, it is not surprising that their form should be similar to pipes. The individual cells of phloem are connected end-to-end, just as the sections of a pipe might be. As the plant grows, new vascular tissue differentiates in the growing tips of the plant. The new tissue is aligned with existing vascular tissue, maintaining its connection throughout the plant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicotyledon
The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, that the seed has two embryonic leaves or cotyledons. There are around 200,000 species within this group. The other group of flowering plants were called monocotyledons (or monocots), typically each having one cotyledon. Historically, these two groups formed the two divisions of the flowering plants. Largely from the 1990s onwards, molecular phylogenetic research confirmed what had already been suspected: that dicotyledons are not a group made up of all the descendants of a common ancestor (i.e., they are not a monophyletic group). Rather, a number of lineages, such as the magnoliids and groups now collectively known as the basal angiosperms, diverged earlier than the monocots did; in other words, monocots evolved from within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seasonality
In time series data, seasonality refers to the trends that occur at specific regular intervals less than a year, such as weekly, monthly, or quarterly. Seasonality may be caused by various factors, such as weather, vacation, and holidays and consists of periodic, repetitive, and generally regular and predictable patterns in the levels of a time series. Seasonal fluctuations in a time series can be contrasted with cyclical patterns. The latter occur when the data exhibits rises and falls that are not of a fixed period. Such non-seasonal fluctuations are usually due to economic conditions and are often related to the "business cycle"; their period usually extends beyond a single year, and the fluctuations are usually of at least two years. Organisations facing seasonal variations, such as ice-cream vendors, are often interested in knowing their performance relative to the normal seasonal variation. Seasonal variations in the labour market can be attributed to the entrance of school ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vascular Bundle
A vascular bundle is a part of the transport system in vascular plants. The transport itself happens in the stem, which exists in two forms: xylem and phloem. Both these tissues are present in a vascular bundle, which in addition will include supporting and protective tissues. There is also a tissue between xylem and phloem, which is the cambium. The xylem typically lies towards the axis ( adaxial) with phloem positioned away from the axis ( abaxial). In a stem or root this means that the xylem is closer to the centre of the stem or root while the phloem is closer to the exterior. In a leaf, the adaxial surface of the leaf will usually be the upper side, with the abaxial surface the lower side. The sugars synthesized by the plant with sun light are transported by the phloem, which is closer to the lower surface. Aphids and leaf hoppers feed off of these sugars by tapping into the phloem. This is why aphids and leaf hoppers are typically found on the underside of a l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Growth Ring
Dendrochronology (or tree-ring dating) is the scientific method of dating tree rings (also called growth rings) to the exact year they were formed in a tree. As well as dating them, this can give data for dendroclimatology, the study of climate and atmospheric conditions during different periods in history from the wood of old trees. Dendrochronology derives from the Ancient Greek (), meaning "tree", (), meaning "time", and (), "the study of". Dendrochronology is useful for determining the precise age of samples, especially those that are too recent for radiocarbon dating, which always produces a range rather than an exact date. However, for a precise date of the death of the tree a full sample to the edge is needed, which most trimmed timber will not provide. It also gives data on the timing of events and rates of change in the environment (most prominently climate) and also in wood found in archaeology or works of art and architecture, such as old panel paintings. It is als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Stem
A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaf, leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, engages in photosynthesis, stores nutrients, and produces new living tissue. The stem can also be called the culm, halm, haulm, stalk, or thyrsus. The stem is normally divided into nodes and internodes: * The nodes are the points of attachment for leaves and can hold one or more leaves. There are sometimes axillary buds between the stem and leaf which can grow into branches (with leaf, leaves, conifer cones, or inflorescence, flowers). Adventitious roots (e.g. brace roots) may also be produced from the nodes. Vines may produce tendrils from nodes. * The internodes distance one node from another. The term "Shoot (botany), shoots" is often confused with "stems"; "shoots" generally refers to new fresh plant growth, including both stems and other str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trunk (botany)
Trunks are the Plant stem, stems of woody plants and the main structural element of trees. The woody part of the trunk consists of dead but structurally significant heartwood and living sapwood, which is used for nutrient storage and transport. Separating the wood from the bark is the Vascular cambium, cambium, from which trunks grow in diameter. Bark is divided between the living inner bark (the phloem), which transports sugars, and the outer bark, which is a dead protective layer. The precise Cell (biology), cellular makeup of these components differs between non-flowering plants (gymnosperms) and flowering plants (Flowering plant, angiosperms). A variety of specialised cells facilitate the storage of carbohydrates, water, minerals, and transport of water, minerals, and hormones around the plant. Growth is achieved by Cell division, division of these cells. Vertical growth is generated from the Meristem, apical meristems (stem tips), and horizontal (radial) growth, from the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocotyledon
Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are flowering plants whose seeds contain only one embryonic leaf, or cotyledon. A monocot taxon has been in use for several decades, but with various ranks and under several different names. The APG IV system recognises its monophyly but does not assign it to a taxonomic rank, and instead uses the term "monocots" to refer to the group. Monocotyledons are contrasted with the dicotyledons, which have two cotyledons. Unlike the monocots however, the dicots are not monophyletic and the two cotyledons are instead the ancestral characteristic of all flowering plants. Botanists now classify dicots into the eudicots ("true dicots") and several basal lineages from which the monocots emerged. The monocots are extremely important economically, culturally, and ecologically, and make up a majority of plant biomass used in agriculture. Common crops such as dates, onions, garlic, rice, wheat, maize, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
