A biome is a distinct geographical region with specific climate, vegetation, and animal life. It consists of a biological community that has formed in response to its physical environment and regional climate. Biomes may span more than one continent. A biome encompasses multiple ecosystems within its boundaries. It can also comprise a variety of habitats.
In physical geography, tundra is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term is a Russian word adapted from Sámi languages. There are three regions and associated types of tundra: Arctic tundra, alpine tundra, and Antarctic tundra.
The American pika, a diurnal species of pika, is found in the mountains of western North America, usually in boulder fields at or above the tree line. They are herbivorous, smaller relatives of rabbits and hares. Pikas have two different ways of foraging; they either directly consume food or they cache food in piles for the winter (haying).
The California Floristic Province (CFP) is a floristic province with a Mediterranean-type climate located on the Pacific Coast of North America with a distinctive flora similar to other regions with a winter rainfall and summer drought climate like the Mediterranean Basin. This biodiversity hotspot is known for being the home of the Sierran giant sequoia tree and its close relative the coast redwood. In 1996, the Province was designated as a biodiversity hotspot allowing it to join ranks among 33 other areas in the world with many endemic species. To be named a biodiversity hotspot, an area has to contain species and plant life that cannot be found anywhere else in the world. The California Floristic Province is home to over 3,000 species of vascular plants, 60% of which are endemic to the province.
The Sierra Nevada subalpine zone refers to a biotic zone below treeline in the Sierra Nevada mountain range of California, United States. This subalpine zone is positioned between the upper montane zone at its lower limit, and tree line at its upper limit.
The plateau pika, also known as the black-lipped pika, is a species of mammal in the pika family, Ochotonidae.
The Ili pika is a species of mammal in the family Ochotonidae, endemic to northwest China. After its discovery in 1983, it was studied for a decade. Increased temperatures, likely from global warming, and increased grazing pressure may have caused the rapid decline in population. According to IUCN last assessed in 2018, the Ili pika is now considered an endangered species, with approximately fewer than 1,000 left.
The court jester hypothesis is used in reference to the idea that abiotic forces, rather than biotic competition between species, function as a major driving force behind the processes in evolution which produce speciation. In evolutionary theory, the court-jester hypothesis contrasts the Red Queen hypothesis.
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial factor in shaping plant community, biodiversity, metabolic processes and ecosystem dynamics for montane ecosystems. Dense montane forests are common at moderate elevations, due to moderate temperatures and high rainfall. At higher elevations, the climate is harsher, with lower temperatures and higher winds, preventing the growth of trees and causing the plant community to transition to montane grasslands and shrublands or alpine tundra. Due to the unique climate conditions of montane ecosystems, they contain increased numbers of endemic species. Montane ecosystems also exhibit variation in ecosystem services, which include carbon storage and water supply.
The Neopluvial was a phase of wetter and colder climate that occurred during the late Holocene in the Western United States. During the Neopluvial, water levels in a number of now-dry lakes and closed lakes such as the Great Salt Lake rose and vegetation changed in response to increased precipitation. The event was not exactly synchronous everywhere, with neopluvial lake-level rises occurring between 6,000 and 2,000 years ago. It is correlative to the Neoglacial period.
Asmeret Asefaw Berhe is a soil biogeochemist and political ecologist who served as Director of the Office of Science at the US Department of Energy from 2022 to 2024. She was previously the Professor of Soil Biogeochemistry and the Ted and Jan Falasco Chair in Earth Sciences and Geology in the Department of Life and Environmental Sciences; University of California, Merced. Her research group worked to understand how soil helps regulate the Earth's climate.
Lisa Welp is a biogeochemist who utilizes stable isotopes to understand how water and carbon dioxide are exchanged between the land and atmosphere. She is a professor at Purdue University in the department of Earth, Atmosphere, and Planetary Sciences.
Nancy Huntly is an American ecologist based at Utah State University, where she is a Professor in the Department of Biology and director of the USU Ecology Center. Her research has been on biodiversity, herbivory, and long-term human ecology. She started her position at USU in 2011, after serving as a Program Officer in the Division of Environmental Biology at the National Science Foundation. Prior to that she was a faculty member in the Department of Biological Sciences at Idaho State University (Pocatello).
Lisa J. Graumlich is an American paleoclimatologist who studies the interactions between the climate, ecosystems and humans. She is the inaugural dean of College of the Environment at the University of Washington. Graumlich is a Fellow of the American Association for the Advancement of Science and the Ecological Society of America, and is president-elect of the American Geophysical Union.
Tana Elaine Wood is a biogeochemist and ecosystem scientist with a focus in land-use and climate change. Her research is focused on looking into how these issues affect tropical forested ecosystems and particularly focuses on soil science and below ground research efforts.
A marine heatwave is a period of abnormally high seawater temperatures compared to the typical temperatures in the past for a particular season and region. Marine heatwaves are caused by a variety of drivers. These include shorter term weather events such as fronts, intraseasonal events, annual, and decadal (10-year) modes like El Niño events, and human-caused climate change. Marine heatwaves affect ecosystems in the oceans. For example, marine heatwaves can lead to severe biodiversity changes such as coral bleaching, sea star wasting disease, harmful algal blooms, and mass mortality of benthic communities. Unlike heatwaves on land, marine heatwaves can extend over vast areas, persist for weeks to months or even years, and occur at subsurface levels.
Adina Merenlender is a Professor of Cooperative Extension in Conservation Science at University of California, Berkeley in the Environmental Science, Policy, and Management Department, and is an internationally recognized conservation biologist known for land-use planning, watershed science, landscape connectivity, and naturalist and stewardship training.
Phyllis Jean Stabeno is a physical oceanographer known for her research on the movement of water in polar regions. She has led award-winning research projects in the Arctic and was noted for a distinguished scientific career by the National Oceanic and Atmospheric Administration.
An alpine lake is a high-altitude lake in a mountainous area, usually near or above the tree line, with extended periods of ice cover. These lakes are commonly glacial lakes formed from glacial activity but can also be formed from geological processes such as volcanic activity or landslides. Many alpine lakes that are fed from glacial meltwater have the characteristic bright turquoise green color as a result of glacial flour, suspended minerals derived from a glacier scouring the bedrock. When active glaciers are not supplying water to the lake, such as a majority of Rocky Mountains alpine lakes in the United States, the lakes may still be bright blue due to the lack of algal growth resulting from cold temperatures, lack of nutrient run-off from surrounding land, and lack of sediment input. The coloration and mountain locations of alpine lakes attract lots of recreational activity.
