Callitris muelleri is a species of conifer in the Cupressaceae family. It is found only in New South Wales, Australia
Callitris endlicheri known as the black cypress pine, is a species of conifer in the Cupressaceae family. It is found only in Australia. Pine Island Reserve
Athrotaxis selaginoides is a species of Athrotaxis, endemic to Tasmania in Australia, where it grows at 400–1,120 m altitude. In its habitat in the mountains, snow in winter is usual, it is called King Billy Pine or King William Pine, although it is not a true pine. It is an evergreen coniferous tree growing to 20–30 m tall, with a trunk up to 1.5 m diameter. The leaves are claw-like, 7–18 mm long and 3–4 mm broad, arranged spirally on the shoots; the seed cones are globose. The pollen cones are 4–5 mm long; the main cause of past decline has been fire, with about one third of its habitat burnt in the twentieth century. Like the other two Athrotaxis species, A. selaginoides is sensitive to fire. Another cause of past decline has been logging; the overall decline is estimated to be about 40% over the last 200 years. This is within the three generation time limit where one generation is estimated to be at least 100 years. Although 84% of forests are now in protected areas, fires still are a potential hazard.
Tasmanian government policy precludes logging of this species outside these protected areas. Away from its native range, it is cultivated as an ornamental tree in northwestern Europe, it succeeds in Scotland where it receives the necessary rainfalls for its good growth and produces fertile seeds there
Taiwan the Republic of China, is a state in East Asia. Neighbouring states include the People's Republic of China to the west, Japan to the northeast, the Philippines to the south. Taiwan is the most populous state and largest economy, not a member of the United Nations; the island of Taiwan was inhabited by indigenous peoples for thousands of years before the 17th century, when Dutch colonialists opened the island to mass Han immigration. After a brief rule by the Kingdom of Tungning, the island was annexed in 1683 by the Qing dynasty of China, ceded to Japan in 1895. Following the surrender of Japan in 1945, the Republic of China, which had overthrown and succeeded the Qing in 1911, took control of Taiwan; the resumption of the Chinese Civil War led to the loss of the mainland to the Communists and the flight of the ROC government to Taiwan in 1949. Although the ROC government continued to claim to be the legitimate representative of China, since 1950 its effective jurisdiction has been limited to Taiwan and several small islands.
In the early 1960s, Taiwan entered a period of industrialisation. In the 1980s and early 1990s, it changed from a one-party military dictatorship to a multi-party democracy with a semi-presidential system; as a founding member, the ROC represented China in the UN until it was replaced by the PRC in 1971. The PRC has claimed sovereignty over Taiwan and refused diplomatic relations with any country that recognises the ROC; as of 2019, Taiwan maintains official ties with 16 out of 193 UN member states. Most international organisations in which the PRC participates either refuse to grant membership to Taiwan or allow it to participate only as a non-state actor. Most major powers maintain unofficial ties with Taiwan through representative offices and institutions that function as de facto embassies and consulates. In Taiwan, the major political division is between parties favouring eventual Chinese unification and promoting a Chinese identity contrasted with those aspiring to independence and promoting a Taiwanese identity, though both sides have moderated their positions to broaden their appeal.
Taiwan is a high-income advanced economy, with a skilled and educated workforce. It has the 22nd-largest economy in the world, its high-tech industry plays a key role in the global economy, it is urbanised, is one of the most densely populated countries in the world, with most of the population concentrated on the western coast. The state is ranked in terms of civil and political liberties, health care and human development. Various names for the island of Taiwan remain in use today, each derived from explorers or rulers during a particular historical period; the name Formosa dates from 1542, when Portuguese sailors sighted an uncharted island and noted it on their maps as Ilha Formosa. The name Formosa "replaced all others in European literature" and remained in common use among English speakers into the 20th century. In the early 17th century, the Dutch East India Company established a commercial post at Fort Zeelandia on a coastal sandbar called "Tayouan", after their ethnonym for a nearby Taiwanese aboriginal tribe Taivoan people, written by the Dutch and Portuguese variously as Taiouwang, Teijoan, etc.
This name was adopted into the Chinese vernacular as the name of the sandbar and nearby area. The modern word "Taiwan" is derived from this usage, seen in various forms in Chinese historical records; the area occupied by modern-day Tainan represented the first permanent settlement by both European colonists and Chinese immigrants. The settlement grew to be the island's most important trading centre and served as its capital until 1887. Use of the current Chinese name became official as early as 1684 with the establishment of Taiwan Prefecture. Through its rapid development the entire Formosan mainland became known as "Taiwan". In his Daoyi Zhilüe, Wang Dayuan used "Liuqiu" as a name for the island of Taiwan, or the part of it closest to Penghu. Elsewhere, the name was used for the Ryukyu Islands in general or Okinawa, the largest of them; the name appears in the Book of Sui and other early works, but scholars cannot agree on whether these references are to the Ryukyus, Taiwan or Luzon. The official name of the state is the "Republic of China".
Shortly after the ROC's establishment in 1912, while it was still located on the Chinese mainland, the government used the short form "China" to refer to itself, which derives from zhōng and guó, a term which developed under the Zhou dynasty in reference to its royal demesne, the name was applied to the area around Luoyi during the Eastern Zhou and to China's Central Plain before being used as an occasional synonym for the state during the Qing era. During the 1950s and 1960s, after the government had withdrawn to Taiwan upon losing the Chinese Civil War, it was referred to as "Nationalist China" to differentiate it from "Communist China", it was a member of the United Nations representing "China" until 1971, when it lost its seat to the People's Republic of China. Over subsequent decades, the Republic of China has become known as "Taiwan", after the island that comprises 99% of the territory under its control. In some contexts ROC government publications, the name is written as "
Libocedrus bidwillii variously called pāhautea, kaikawaka or New Zealand cedar is a species of Libocedrus, endemic to New Zealand in both the North and South Islands. It grows at 250–1,200 m altitude in temperate rainforests, it is an evergreen coniferous tree growing to 25 m tall, with a trunk up to 1.5 m diameter. The foliage is arranged in flattened sprays; the seed cones are cylindrical, 8–12 mm long, with four scales each with a prominent curved spine-like bract. They are mature about six to eight months after pollination; the pollen cones are 2.5–5 mm long. The timber becomes commercially available, it is light in weight and a distinct light purple when cut. The timber in small dimension sizes is prone to twist when cut, it is sometimes used for lightweight sailing boat construction. It glues and holds ring nails well
In botany, a stoma called a stomate, is a pore, found in the epidermis of leaves and other organs, that facilitates gas exchange. The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the stomatal opening; the term is used collectively to refer to the entire stomatal complex, consisting of the paired guard cells and the pore itself, referred to as the stomatal aperture. Air enters the plant through these openings by gaseous diffusion, contains carbon dioxide and oxygen, which are used in photosynthesis and respiration, respectively. Oxygen produced as a by-product of photosynthesis diffuses out to the atmosphere through these same openings. Water vapor diffuses through the stomata into the atmosphere in a process called transpiration. Stomata are present in the sporophyte generation of all land plant groups except liverworts. In vascular plants the number and distribution of stomata varies widely. Dicotyledons have more stomata on the lower surface of the leaves than the upper surface.
Monocotyledons such as onion and maize may have about the same number of stomata on both leaf surfaces. In plants with floating leaves, stomata may be found only on the upper epidermis and submerged leaves may lack stomata entirely. Most tree species have stomata only on the lower leaf surface. Leaves with stomata on both the upper and lower leaf are called. Size varies across species, with end-to-end lengths ranging from 10 to 80 µm and width ranging from a few to 50 µm. Carbon dioxide, a key reactant in photosynthesis, is present in the atmosphere at a concentration of about 400 ppm. Most plants require the stomata to be open during daytime; the air spaces in the leaf are saturated with water vapour, which exits the leaf through the stomata. Therefore, plants cannot gain carbon dioxide without losing water vapour. Ordinarily, carbon dioxide is fixed to ribulose-1,5-bisphosphate by the enzyme RuBisCO in mesophyll cells exposed directly to the air spaces inside the leaf; this exacerbates the transpiration problem for two reasons: first, RuBisCo has a low affinity for carbon dioxide, second, it fixes oxygen to RuBP, wasting energy and carbon in a process called photorespiration.
For both of these reasons, RuBisCo needs high carbon dioxide concentrations, which means wide stomatal apertures and, as a consequence, high water loss. Narrower stomatal apertures can be used in conjunction with an intermediary molecule with a high carbon dioxide affinity, PEPcase. Retrieving the products of carbon fixation from PEPCase is an energy-intensive process, however; as a result, the PEPCase alternative is preferable only where water is limiting but light is plentiful, or where high temperatures increase the solubility of oxygen relative to that of carbon dioxide, magnifying RuBisCo's oxygenation problem. A group of desert plants called "CAM" plants open their stomata at night, use PEPcarboxylase to fix carbon dioxide and store the products in large vacuoles; the following day, they close their stomata and release the carbon dioxide fixed the previous night into the presence of RuBisCO. This saturates RuBisCO with carbon dioxide; this approach, however, is limited by the capacity to store fixed carbon in the vacuoles, so it is preferable only when water is limited.
However, most plants do not have the aforementioned facility and must therefore open and close their stomata during the daytime, in response to changing conditions, such as light intensity and carbon dioxide concentration. It is not certain how these responses work. However, the basic mechanism involves regulation of osmotic pressure; when conditions are conducive to stomatal opening, a proton pump drives protons from the guard cells. This means that the cells' electrical potential becomes negative; the negative potential opens potassium voltage-gated channels and so an uptake of potassium ions occurs. To maintain this internal negative voltage so that entry of potassium ions does not stop, negative ions balance the influx of potassium. In some cases, chloride ions enter, while in other plants the organic ion malate is produced in guard cells; this increase in solute concentration lowers the water potential inside the cell, which results in the diffusion of water into the cell through osmosis.
This increases the cell's turgor pressure. Because of rings of cellulose microfibrils that prevent the width of the guard cells from swelling, thus only allow the extra turgor pressure to elongate the guard cells, whose ends are held in place by surrounding epidermal cells, the two guard cells lengthen by bowing apart from one another, creating an open pore through which gas can move; when the roots begin to sense a water shortage in the soil, abscisic acid is released. ABA binds to receptor proteins in the guard cells' plasma membrane and cytosol, which first raises the pH of the cytosol of the cells and cause the concentration of free Ca2+ to increase in the cytosol due to influx from outside the cell and release of Ca2+ from internal stores such as the endoplasmic reticulum and vacuoles; this caus
The order Pinales in the division Pinophyta, class Pinopsida, comprises all the extant conifers. This order used to be known as the Coniferales; the distinguishing characteristic is the reproductive structure known as a cone produced by all Pinales. All of the extant conifers, such as cedar, celery-pine, fir, larch, redwood and yew, are included here; some fossil conifers, belong to other distinct orders within the division Pinophyta. The yews had been separated into a distinct order of their own, but genetic evidence indicates yews are monophyletic with other conifers and they are now included in the Pinales; the families included are the Araucariaceae, Pinaceae, Podocarpaceae and Taxaceae