Bamboo blossoming is a natural phenomenon in which the bamboos in a location blossom and become hung with bamboo seeds.
Bamboo blossoming is a natural phenomenon in which the bamboos in a location blossom and become hung with bamboo seeds.
Bamboos usually have a life cycle around 40 to 80 years, varying among species. Normally, new bamboos grow up from bamboo shoots at the roots. At infrequent intervals for most species, they will start to blossom. After blossom, flowers produce fruit (called "bamboo rice" in parts of India and China). Following this, the bamboo forest dies out. Since a bamboo forest usually grows from a single bamboo, the death of bamboos occurs in a large area.
Many bamboo species flower at extremely long intervals such as 65 or even 120 years. These taxa exhibit mass flowering (or gregarious flowering), with all plants in a particular cohort flowering over a several-year period. Any plant derived through clonal propagation from this cohort will also flower regardless of whether it has been planted in a different location. The longest mass flowering interval known is 130 years, for the species Phyllostachys bambusoides (Sieb. & Zucc.). In this species, all plants of the same stock flower at the same time, regardless of differences in geographic locations or climatic conditions, and then die. The lack of environmental impact on the time of flowering indicates the presence of some sort of "alarm clock" in each cell of the plant which signals the cessation of vegetative growth and the diversion of all energy to flower production. [1] This mechanism, as well as the evolutionary cause behind it, is still largely a mystery.
One hypothesis to explain the evolution of this semelparous mass flowering phenomenon is the predator satiation hypothesis, which argues that by fruiting at the same time, a population increases the survival rate of their seeds by flooding the area with fruit. Therefore, even if predators eat their fill, seeds will still be left over. By having a flowering cycle longer than the lifespan of the rodent predators, bamboos can regulate animal populations by causing starvation during the period between flowering events. Thus, the death of the adult clone is due to resource exhaustion, as it would be more effective for parent plants to devote all resources to creating a large seed crop than to hold back energy for their own regeneration. [2]
Another hypothesis, called the fire cycle hypothesis, argues that periodic flowering followed by death of the adult plants has evolved as a mechanism to create disturbance in the habitat, thus providing the seedlings with a gap in which to grow. This argues that the dead culms create a large fuel load, and also a large target for lightning strikes, increasing the likelihood of wildfire. [3] Because bamboos can be aggressive as early successional plants, the seedlings would be able to outstrip other plants and take over the space left by their parents.
However, both have been disputed for different reasons. The predator satiation hypothesis does not explain why the flowering cycle is 10 times longer than the lifespan of the local rodents, something not predicted. The bamboo fire cycle hypothesis is considered by a few scientists to be unreasonable; they argue [4] that fires only result from humans and no natural fires occur in India. This notion is considered wrong based on distribution of lightning strike data during the dry season throughout India. However, another argument against this is the lack of precedent for any living organism to harness something as unpredictable as lightning strikes to increase its chance of survival as part of natural evolutionary progress. [5]
More recently, a mathematical explanation for the extreme length of the flowering cycles has been offered, involving both the stabilising selection implied by the predator satiation hypothesis and others, and the fact that plants that flower at longer intervals tend to release more seeds. [6] [7] The hypothesis claims that bamboo flowering intervals grew by integer multiplication. A mutant bamboo plant flowering at a noninteger multiple of its population's flowering interval would release its seeds alone, and would not enjoy the benefits of collective flowering (such as protection from predators). However, a mutant bamboo plant flowering at an integer multiple of its population's flowering interval would release its seeds only during collective flowering events, and would release more seeds than the average plant in the population. It could, therefore, take over the population, establishing a flowering interval that is an integer multiple of the previous flowering interval. The hypothesis predicts that observed bamboo flowering intervals should factorize into small prime numbers.
The mass fruiting also has direct economic and ecological consequences, however. For example, devastating consequences occur when the Melocanna bambusoides population flowers and fruits once every 30–35 years [8] around the Bay of Bengal. The death of the bamboo plants following their fruiting means the local people lose their building material, and the large increase in bamboo fruit leads to a rapid increase in rodent populations. As the number of rodents increases, they consume all available food, including grain fields and stored food, sometimes leading to famine. [9] These rats can also carry dangerous diseases, such as typhus, typhoid, and bubonic plague, which can reach epidemic proportions as the rodents increase in number. [1] [2] The relationship between rat populations and bamboo flowering was examined in a 2009 Nova documentary Rat Attack .
The sudden death of large areas of bamboo puts pressure on animals that depend on bamboo as a food source, such as the endangered giant panda. [10] It has also been hypothesized that ancestors of the domesticated chicken adapted to this sporadic burst of food supply by aggressively laying eggs when the blossom and seed dispersal occurs. [11]
Flowering produces large quantities of seeds, typically suspended from the ends of the branches. These seeds give rise to a new generation of plants that may be identical in appearance to those that preceded the flowering, or they may produce new cultivars with different characteristics, such as the presence or absence of striping or other changes in coloration of the culms.
Several bamboo species are never known to set seed even when sporadically flowering has been reported. Bambusa vulgaris , Bambusa balcooa , and Dendrocalamus stocksii are common examples of such bamboo. [12]
Chaparral is a shrubland plant community found primarily in California, in southern Oregon and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean climate and infrequent, high-intensity crown fires.
Bamboos are a diverse group of mostly evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family, in the case of Dendrocalamus sinicus having individual stalks (culms) reaching a length of 46 meters, up to 36 centimeters in thickness and a weight of up to 450 kilograms. The internodes of bamboos can also be of great length. Kinabaluchloa wrayi has internodes up to 2.5 meters in length. and Arthrostylidium schomburgkii has internodes up to 5 meters in length, exceeded in length only by papyrus. By contrast, the stalks of the tiny bamboo Raddiella vanessiae of the savannas of French Guiana measure only 10–20 millimeters in length by about two millimeters in width. The origin of the word "bamboo" is uncertain, but it probably comes from the Dutch or Portuguese language, which originally borrowed it from Malay or Kannada.
Lodoicea, commonly known as the sea coconut, coco de mer, or double coconut, is a monotypic genus in the palm family. The sole species, Lodoicea maldivica, is endemic to the islands of Praslin and Curieuse in the Seychelles. It has the largest seed in the plant kingdom. It was also formerly found on the small islets of St Pierre, Chauve-Souris, and Ile Ronde, all located near Praslin, but had become extinct there for a time until recently reintroduced.
In spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, such as the wind, and living (biotic) vectors such as birds. Seeds can be dispersed away from the parent plant individually or collectively, as well as dispersed in both space and time. The patterns of seed dispersal are determined in large part by the dispersal mechanism and this has important implications for the demographic and genetic structure of plant populations, as well as migration patterns and species interactions. There are five main modes of seed dispersal: gravity, wind, ballistic, water, and by animals. Some plants are serotinous and only disperse their seeds in response to an environmental stimulus. These modes are typically inferred based on adaptations, such as wings or fleshy fruit. However, this simplified view may ignore complexity in dispersal. Plants can disperse via modes without possessing the typical associated adaptations and plant traits may be multifunctional.
Shorea is a genus of about 196 species of mainly rainforest trees in the family Dipterocarpaceae. The genus is named after Sir John Shore, the governor-general of the British East India Company, 1793–1798. The timber of trees of the genus is sold under the common names lauan, luan, lawaan, meranti, seraya, balau, bangkirai, and Philippine mahogany.
Mast is the fruit of forest trees and shrubs, such as acorns and other nuts. The term derives from the Old English mæst, meaning the nuts of forest trees that have accumulated on the ground, especially those used historically for fattening domestic pigs, and as food resources for wildlife. In the aseasonal tropics of Southeast Asia, entire forests, including hundreds of species of trees and shrubs, are known to mast at irregular periods of 2–12 years.
Rhus ovata, commonly known as sugar bush or sugar sumac, is a shrub or small tree found growing in the canyons and slopes of the chaparral and related ecosystems in Southern California, Arizona, Baja California and Baja California Sur. It is a long lived-plant, up to 100 years, and has dense evergreen foliage that make it conspicuous. It is closely related to and hybridizes with the lemonade sumac.
Plietesials are plants that grow for a number of years, flower gregariously (synchronously), set seed and then die. The length of the cycle can vary between 8 and 16 years. For example, the neelakurinji plant flowers every 12 years and bloomed as expected in 2006 and 2018 in the Munnar region of Kerala, India.
Mautâm is a cyclic ecological phenomenon that occurs every 48–50 years in the northeastern Indian states of Tripura, Mizoram and Manipur, as well as in many places of Assam which are 30% covered by wild bamboo forests, and Chin State in Myanmar, particularly Hakha, Thantlang, Falam, Paletwa and Matupi Townships. It begins with a rat population boom, which in turn creates a widespread famine in those areas.
Seed predation, often referred to as granivory, is a type of plant-animal interaction in which granivores feed on the seeds of plants as a main or exclusive food source, in many cases leaving the seeds damaged and not viable. Granivores are found across many families of vertebrates as well as invertebrates ; thus, seed predation occurs in virtually all terrestrial ecosystems.
Bambusa vulgaris, common bamboo, is an open-clump type bamboo species. It is native to Bangladesh, India, Sri Lanka, Southeast Asia, and to the province of Yunnan in southern China, but it has been widely cultivated in many other places and has become naturalized in several regions. Among bamboo species, it is one of the largest and most easily recognized.
Oligoryzomys longicaudatus, also known as the long-tailed colilargo or long-tailed pygmy rice rat, is a species of rodent in the genus Oligoryzomys of the family Cricetidae. It is found in the southern Andes of Chile and Argentina, with an outlying population in eastern Argentina. As a common species with a wide range and a stable population, the International Union for Conservation of Nature has rated this rodent as being of "least concern".
Predator satiation is an anti-predator adaptation in which prey briefly occur at high population densities, reducing the probability of an individual organism being eaten. When predators are flooded with potential prey, they can consume only a certain amount, so by occurring at high densities prey benefit from a safety in numbers effect. This strategy has evolved in a diverse range of prey, including notably many species of plants, insects, and fish. Predator satiation can be considered a type of refuge from predators.
Phyllostachys edulis, the mōsō bamboo, or tortoise-shell bamboo, or mao zhu, , is a temperate species of giant timber bamboo native to China and Taiwan and naturalised elsewhere, including Japan where it is widely distributed from south of Hokkaido to Kagoshima. The edulis part of the Latin name refers to its edible shoots. This bamboo can reach heights of up to 28 m (92 ft). This particular species of bamboo is the most common species used in the bamboo textile industry of China and other countries, for the production of rayon. Moso is less cold-hardy than many phyllostachys, surviving at a reduced height down to 5 degrees Fahrenheit (-15 °C).
Pyrogenic flowering is the fire-adapted trait in plants that is defined by an increase or a peak in flowering after a fire event. Pyrogenic flowering allows for plants to persist in fire-prone environments. Pyrogenic flowering can be facultative, meaning the rate of flowering temporarily increases following burning, or obligate, meaning flowering only occurs post-fire. There is high variation in the length of time between when a fire occurs and when pyrogenic flowering is triggered, and it is frequently species specific. Some pyrogenic flowering does not occur until up to a year post-fire whereas in extreme cases some flowers can emerge just hours after fire disturbance. Precise physiological triggers for pyrogenic flowering have not been heavily studied as is likely to vary between groups. Some suggested stimuli of pyrogenic flowering are the increase in light due to loss of canopy or competition, nutrient changes in the soil, or chemicals associated with fires acting as a trigger.
Phyllostachys bambusoides, commonly called madake, giant timber bamboo, or Japanese timber bamboo, is a species of flowering plant in the bamboo subfamily of the grass family Poaceae, native to China, and possibly also to Japan.
Flowering synchrony is the amount of overlap between flowering periods of plants in their mating season compared to what would be expected to occur randomly under given environmental conditions. A population which is flowering synchronously has more plants flowering at the same time than would be expected to occur randomly. A population which is flowering asynchronously has fewer plants flowering at the same time than would be expected randomly. Flowering synchrony can describe synchrony of flowering periods within a year, across years, and across species in a community. There are fitness benefits and disadvantages to synchronized flowering, and it is a widespread phenomenon across pollination syndromes.
Melocanna baccifera is one of two bamboo species belonging to the Melocanna genus. It grows up to 10–25 m tall. It is native to Bangladesh, Myanmar, India, and Thailand.
Cullenia exarillata is a flowering plant evergreen tree species in the family Malvaceae endemic to the rainforests of the southern Western Ghats in India. It is one of the characteristic trees of the mid-elevation tropical wet evergreen rainforests and an important food plant for the endemic primate, the lion-tailed macaque.
Protea pruinosa, also known as frosted sugarbush or burnished protea, is a flowering shrub which belongs to the genus Protea within the botanical family Proteaceae. The plant is endemic to the southwestern Cape Region of South Africa.