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39-416: Leslie Holdridge established La Selva in 1953. Holdridge was an American botanist and climatologist who is known for his widely used classification system of land areas called The Holdridge Life Zones System . He originally purchased the land to use as a farm for experimenting with mixed agriculture, and was especially interested in experimenting with tree crops that could be planted without total clearing of

78-525: A handful of species in each of the spikemosses , other ferns, Gnetales , and cycads . The first important monograph on epiphytic plant ecology was written by A. F. W. Schimper ( Die epiphytische Vegetation Amerikas , 1888). Assemblages of large epiphytes occur most abundantly in moist tropical forests , but mosses and lichens occur as epiphytes in almost all biomes. In Europe there are no dedicated epiphytic plants using roots, but rich assemblages of mosses and lichens grow on trees in damp areas (mainly

117-425: A significant effect on the microenvironment of their host, and of ecosystems where they are abundant, as they hold water in the canopy and decrease water input to the soil. Some non-vascular epiphytes such as lichens and mosses are well known for their ability to take up water rapidly. Epiphytes create a significantly cooler and more moist environment in the host plant canopy, potentially greatly reducing water loss by

156-431: A workers’ lounge, a researchers’ lounge, a river station, an herbarium, and of course, the surrounding reserve all for research purposes. Researchers can live on site at the station for anywhere between a few days to several months. To accommodate researchers there are cabin dormitories, family housing, a laundry room, a dining hall, and even a gift shop. Most of the tropical ecology research done by scientists at La Selva

195-412: Is a stub . You can help Misplaced Pages by expanding it . Epiphytes An epiphyte is a plant or plant-like organism that grows on the surface of another plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phorophytes . Epiphytes take part in nutrient cycles and add to both

234-399: Is a plant that spends only half of its life without the ground before the roots can reach or make contact with the ground. Orchids are a common example of holo-epiphytes and Strangler Figs are an example of hemi-epiphytes. Epiphytes are not connected to the soil, and consequently must get nutrients from other sources, such as fog, dew, rain and mist, or from nutrients being released from

273-433: Is about 35 meters above sea level, but it quickly gives way to steep hills that reach up to 137 meters elevation at the southwest corner. The altitudinal transect connecting La Selva Biological Station to the main body of Braulio Carrillo National Park (approximately 55 km) extends from La Selva to Barva Volcano and includes tropical wet, premontane rain, lower montane rain, and montane rain forest ecosystems. Located at

312-415: Is needed, evidence suggests that insectivorous birds have a significant impact on levels of herbivory , and the loss of a significant fraction of an entire guild , specifically forest understory insectivores, and then top down trophic cascades could alter arthropod and plant communities and ultimately biodiversity. Leslie Holdridge Leslie Ransselaer Holdridge (September 29, 1907 – June 19, 1999)

351-457: Is not a plant may be called an epibiont . Epiphytes are usually found in the temperate zone (e.g., many mosses , liverworts , lichens , and algae ) or in the tropics (e.g., many ferns , cacti , orchids , and bromeliads ). Epiphyte species make good houseplants due to their minimal water and soil requirements. Epiphytes provide a rich and diverse habitat for other organisms including animals, fungi, bacteria, and myxomycetes . Epiphyte

390-607: Is one of the subdivisions of the Raunkiær system . The term epiphytic derives from the Greek epi- (meaning 'upon') and phyton (meaning 'plant'). Epiphytic plants are sometimes called "air plants" because they do not root in soil. However, that term is inaccurate, as there are many aquatic species of algae that are epiphytes on other aquatic plants (seaweeds or aquatic angiosperms ). The best-known epiphytic plants include mosses , orchids , and bromeliads such as Spanish moss (of

429-463: Is rarely long or severe. La Selva's biological resources are rich and largely intact which generates high biological diversity and productivity. The reserve is home to a wide range of wildlife, including large predators, rare birds, and an astonishing number of invertebrates. It is estimated that La Selva contains over 500,000 species, with more than half (about 300,000) consisting of insect species. Four major tropical life zones are protected between

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468-454: Is related to one of these topics: interactions among interdependent species, carbon sequestration in forests, effects of climate change on ecosystems, mechanisms of speciation, food web dynamics, and maintenance of biodiversity Since there are many endangered species in tropical areas, a great amount of research is conducted on these species. Many researchers write papers analyzing data illustrating species’ decline, and often include thoughts on

507-618: The La Selva and its connection to Braulio Carrillo National Park. Within this reserve, more than 5,000 species of vascular plants can be found, of which more than 700 species are trees. La Selva hosts a large variety of epiphytes , epiphylls, and many climbing aroids . Other common tree species include Welfia regia , Socratea exorrhiza , and most notably Pentaclethra macroloba , which occur in an unusual abundance. There are many mammalian species including large predators such as jaguars ( Jaguar ) and pumas ( Puma (genus) ). According to

546-517: The OTS Website [1] , five of the six species of felines in the country are found within the reserve. Some other species include the collared peccary ( Tayassu tajacu ) and Hoffmann's two-toed sloth ( Choloepus hoffmanni ). The large number of bird species found here exceeds any other site in Central America. The most recent list published includes 467 species of birds. When taking into account

585-657: The Station to the north, the Peje River to the west, and the Sábalo-Esquina creeks to the east. Braulio Carrillo National Park (47,000 ha) is adjacent to the southern border of the Station and is connected via a 4–6 km wide protected corridor. The closest communities to the Station are La Flamínea (at its north-eastern border) and El Tigre (7 km south-east). Each of these communities has approximately 500 residents and they were established as recently as 1985. Puerto Viejo,

624-471: The avifauna most sensitive to environmental changes, in general, are the mixed flocks of ant followers and under-story insectivores. Along altitudinal gradients such as those observed in La Selva, species diversity and community composition of birds change rapidly. Elevational and latitudinal migrants, single and mixed flocks, threatened and endangered species, along with many other groups can be found in this area. Wide arrays of trophic groups are present, but

663-710: The bushmaster Lachesis (genus) . Despite the high diversity of plants and vertebrates, these numbers are dwarfed by its invertebrate fauna. Over 450 ant species have been collected at La Selva, with many still undescribed and there are more than 5,000 moth species (many undescribed). A more complete species list can be found at the Organization for Tropical Studies site. [2] There is a great amount of research conducted at La Selva Biological Station. Each year, more than 240 papers are published from studies performed there. The station has grown and expanded its facilities to include two laboratories, workspaces, an academic center,

702-577: The capital of the Cantón Sarapiquí in the province of Heredia, is the nearest major town, with approximately 1,163 residents, and is located seven kilometers north-east of La Selva. La Selva Biological Station is only 2 hours by car from San José airport. Of the total La Selva property (1,536 ha), 55% is characterized as species-rich, multilayered communities of primary forest. These forests contain impressive trees, lianas , epiphytes , palms, and many other broad-leaved monocots. The remaining areas of

741-502: The confluence of the Puerto Viejo and Sarapiquí Rivers, which meet at the station's northern border, the preserve is surrounded on three sides by the natural barriers created by these rivers and their tributaries . The soils along the rivers are composed of Holocene and Pleistocene alluvia and consist primarily of inceptisols with occasional entisols . La Selva's uplands, on the other hand, begin several hundred meters inland from

780-437: The conservation efforts needed to preserve them. And because humans are a major factor causing the endangerment of many of these species, mostly through habitat loss from human practices, there is extensive research done on impacts of humans in tropical forests. Research is done both on the effects of large companies conducting oil and mineral exploration, creating plantations, or cattle farming and also on local peoples who live in

819-411: The diversity and biomass of the ecosystem in which they occur, like any other organism. They are an important source of food for many species. Typically, the older parts of a plant will have more epiphytes growing on them. Epiphytes differ from parasites in that they grow on other plants for physical support and do not necessarily affect the host negatively. An organism that grows on another organism that

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858-410: The forest and use its resources. Examples of research projects conducted at La Selva: The TREES project was established by David Clark and Deborah Clark in 1983 when they were Directors of the Station. It ran until 2015 and provided an annual census of tropical tree performance and microsite condition. Due to La Selva's large area and the fact that many people are permanent residents living within

897-417: The genus Tillandsia ), but epiphytes may be found in every major group of the plant kingdom. Eighty-nine percent of (or about 24,000) terrestrial epiphyte species are flowering plants . The second largest group are the leptosporangiate ferns , with about 2,800 species (10% of epiphytes). About one-third of all fern species are epiphytes. The third largest group is clubmosses , with 190 species, followed by

936-422: The ground rooted plants by decomposition or leaching, and dinitrogen fixation. Epiphytic plants attached to their hosts high in the canopy have an advantage over herbs restricted to the ground where there is less light and herbivores may be more active. Epiphytic plants are also important to certain animals that may live in their water reservoirs, such as some types of frogs and arthropods . Epiphytes can have

975-873: The host through transpiration. CAM metabolism , a water-preserving metabolism present among various plant taxa , is particularly relevant to epiphytic communities. For example, it is estimated that among epiphytic orchids, as many as 50% are likely to use it. Other relevant epiphytic families which display such metabolism are Bromeliacee (e.g. in genera Aechmea and Tillandsia ), Cactaceae (e.g. in Rhipsalis and Epiphyllum ) and Apocynaceae (e.g. in Hoya and Dischidia ). The ecology of epiphytes in marine environments differs from those in terrestrial ecosystems. Epiphytes in marine systems are species of algae, bacteria, fungi, sponges, bryozoans, ascidians, protozoa, crustaceans, molluscs and any other sessile organism that grows on

1014-541: The most common types are arboreal frugivores, arboreal frugivore/insectivores, foliage insectivores, and nectarivore/insectivores. La Selva's rivers contain an order of magnitude fewer species than the large, continental, Neotropical rivers such as the Amazon and Orinoco . Despite this notable difference, the two rivers and 13 streams flowing through La Selva support many species of Characidae , Poeciliidae , Cichlidae , and others. Large predators are also represented by

1053-476: The most popular hunted species. Additionally, there have been many changes in abundance and species composition within La Selva Biological Station over the past few decades. For example, there have been significant changes to the list of bird species found within the reserve. Since 1960, most of the forest surrounding the Station has been converted to agricultural uses. Although, further research

1092-425: The native forest. In the beginning, La Selva was a challenge to get to; the trip required a long, treacherous dirt road followed by a 4-kilometer dugout canoe trip. In 1968 the Organization of Tropical Studies (OTS) bought the area for fifty thousand US dollars to be used as a private reserve and biological station. OTS was a small, 5-year-old organization created with the goal of facilitating research and education in

1131-475: The reserve consist of abandoned pastures and plantations in various stages of succession, selectively logged secondary forest, or plots designated for experimental use. The reserve is located at the physiographic transition from the low, steep foothills of the Central Volcanic Cordillera to the vast Caribbean coastal plain in northeastern Costa Rica. At the northern end of the property the elevation

1170-611: The reserve is illegal hunting within the reserve's land. Results of an oral questionnaire given to local residents of the reserve showed that 4% admitted to hunting within the year prior to the survey while 86% denied any hunting activity. 8% of respondents did not know if anyone in their household had hunted and 2% expressed no opinion. Species reported by the respondents to have been hunted included iguana ( Iguana iguana ), deer ( Mazama americana , Odocoileus virginianus ), tinamou ( Tinamidae ), bobo fish ( Joturus pichardi ) and paca ( Agouti paca ). Bobo fish, paca, and tinamou were

1209-612: The reserve, potential threats to the station and the surrounding area do exist. Wild habitats and habitat connectivity in the region are seriously threatened by deforestation and wetland loss. Solutions to habitat fragmentation and loss have been proposed by the Executive Committee that oversees the San Juan-La Selva Biological Corridor. A biological corridor would effectively bridge habitat gaps and allow species to migrate as normal Another potential threat to

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1248-416: The surface of a plant, typically seagrasses or algae. Settlement of epiphytic species is influenced by a number of factors including light, temperature, currents, nutrients, and trophic interactions. Algae are the most common group of epiphytes in marine systems. Photosynthetic epiphytes account for a large amount of the photosynthesis in systems in which they occur. This is typically between 20 and 60% of

1287-872: The total number of species found one must understand that many are rare or may have been seen by mistake. Of these species, more than half breed locally, and many are altitudinal migrants or North American overwintering migrants. Several ecological variables influence the vulnerability to habitat fragmentation , and other changes in the environment, in various groups of avifauna: diet, habitat, propensity to join mixed-species flocks, and nest type. Insectivorous birds are particularly sensitive to fragmentation, perhaps due to their dietary or foraging substrate specialization; forest under-story birds are most vulnerable to changes in their habitat; mixed-species flocks are especially sensitive to fragmentation as they typically roam over large areas; and certain nest types are more vulnerable to predation than others. According to Matlock and Hartshorn,

1326-416: The total primary production of the ecosystem. They are a general group of organisms and are highly diverse, providing food for a great number of fauna. Snail and nudibranch species are two common grazers of epiphytes. Epiphyte species composition and the amount of epiphytes can be indicative of changes in the environment. Recent increases in epiphyte abundance have been linked to excessive nitrogen put into

1365-402: The tropics. Holdridge encouraged OTS to use La Selva as a research site even before it became OTS property. Holdridge supported research at La Selva until his death in 1999. Since the station's beginnings in 1953, there have been immense changes: access is easy, buildings have been constructed, and the preserve has tripled in size. It is now one of the most important sites for tropical research in

1404-427: The two rivers and are composed primarily of utisols. Temperature variation is slight year round, and daily temperatures can fluctuate from 19 to 31 °C (66 to 88 °F). As the climate is tropical wet, rain is common throughout the year, and the average annual rainfall is 4 meters (13 feet). The rainiest months are July, November, and December, while the least rainy season is from February to April. The dry season

1443-405: The western coastal fringe), and the common polypody fern grows epiphytically along branches. Rarely, grass, small bushes or small trees may grow in suspended soils up trees (typically in a rot-hole). Epiphytes however, can generally be categorized into holo-epiphytes or hemi-epiphytes. A holo-epiphyte is a plant that spends its whole life cycle without contact with the ground and a hemi-epiphyte

1482-553: The world. In the past few decades, however, the human population around the Station have increased rapidly due to several factors, including the expansion of banana production and government settlement projects. La Selva Biological Station is located in the Central Conservation Area (91,000 ha) in the north-eastern lowlands of Costa Rica (10°26´ N, 83°59´ W). It encompasses 1,536 ha of classic-lowland tropical rain forest. The Sarapiquí and Puerto Viejo Rivers border

1521-728: Was an American botanist and climatologist . In his famous 1947 paper, he defined "life zones" using three indicators: Holdridge participated in the Cinchona Missions , a United States effort to search for natural sources of quinine during World War II . He was the father of composer Lee Holdridge as well as the father of Leslie A. Holdridge, Lorena Holdridge, Marbella Holdridge, Marly Holdridge, Marisela Holdridge, Thania Holdridge, John Holdridge, Ida Holdridge, Reuseland Holdridge, Leythy J. Holdridge and youngest son Gregory Holdridge whom he fathered with Costa Rican Clara Luz Melendez. This article about an American botanist

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