Ombrotrophic ("cloud-fed"), from

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

ὄμβρος (''ómvros'') meaning "rain" and τροφή (''trofí'') meaning "food"), refers to

soils Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by restri ...

or vegetation which receive all of their water and nutrients from

precipitation In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. The main forms of precipitation include drizzle, rain, rain and snow mixed ("sleet" in Commonwe ...

, rather than from streams or springs. Such environments are hydrologically isolated from the surrounding landscape, and since rain is

acid An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...

ic and very low in

nutrients A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excret ...

, they are home to organisms tolerant of acidic, low-nutrient environments. The vegetation of ombrotrophic

peatland A peatland is a type of wetland whose soils consist of Soil organic matter, organic matter from decaying plants, forming layers of peat. Peatlands arise because of incomplete decomposition of organic matter, usually litter from vegetation, du ...

s is often

bog A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and musk ...

, dominated by ''

Sphagnum ''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store water, since ...

'' mosses. The

hydrology Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and drainage basin sustainability. A practitioner of hydrology is called a hydro ...

of these environments are directly related to their

climate Climate is the long-term weather pattern in a region, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteoro ...

, as precipitation is the water and nutrient source, and temperatures dictate how quickly water evaporates from these systems. Ombrotrophic circumstances may occur even in landscapes composed of

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

or other nutrient-rich substrates – for example, in high-rainfall areas, limestone boulders may be capped by acidic ombrotrophic bog vegetation.

Epiphytic 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 epiphyt ...

vegetation (plants growing on other plants) is ombrotrophic. In contrast to ombrotrophic environments,

minerotrophic Minerotrophic refers to environments that receive nutrients primarily through groundwater that flows through mineral-rich soils or rock,Environment Canada (2014). Ontario wetland evaluation system: Northern Manual, 1st edition, version 3.2. Queen’ ...

environments are those where the water supply comes mainly from streams or springs. This water has flowed over or through rocks often acquiring dissolved chemicals which raise the nutrient levels and reduce the acidity, which leads to different vegetation such as

fen A fen is a type of peat-accumulating wetland fed by mineral-rich ground or surface water. It is one of the main types of wetland along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known as mires ...

poor fen A fen is a type of peat-accumulating wetland fed by mineral-rich Groundwater, ground or surface water. It is one of the main types of wetland along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known ...

. In most cases, ombrotrophic bogs are extremely nutrient deficient, relying solely on

and atmospheric

dust Dust is made of particle size, fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil lifted by wind (an aeolian processes, aeolian process), Types of volcan ...

for nutrient supply. This deficiency is a key characteristic of these ecosystems. However, while ombrotrophic

peat Peat is an accumulation of partially Decomposition, decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, Moorland, moors, or muskegs. ''Sphagnum'' moss, also called peat moss, is one of the most ...

decomposes slowly, some nutrient release does occur. For example, microelements like

zinc Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic tabl ...

(Zn),

copper Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...

(Cu), and

manganese Manganese is a chemical element; it has Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese was first isolated in the 1770s. It is a transition m ...

(Mn) are easily mobilized. Additionally, the presence of more nutrient-demanding species in drainage channels draining ombrotrophic bog areas suggests nutrient removal from these ecosystems.

Vegetation Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular Taxon, taxa, life forms, structure, Spatial ecology, spatial extent, or any other specific Botany, botanic ...

in ombrotrophic bogs is adapted to survive in nutrient-poor conditions, with Sphagnum mosses playing a critical role in its

nutrient cycle A nutrient cycle (or ecological recycling) is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cyc ...

and retention. The addition of extra nutrients and its effects on vegetation and the

carbon cycle The carbon cycle is a part of the biogeochemical cycle where carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of Earth. Other major biogeochemical cycles include the nitrogen cycle and the water cycl ...

can impact an ombrotrophic bog. Increased atmospheric

nitrogen Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. ...

(N) deposition is a major concern in northern ecosystems, which are typically nutrient-limited. Some studies suggest that N deposition may increase ecosystems'

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

() sink potential by stimulating plant productivity. High N deposition levels in

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

have led to changes in plant species composition in

peatlands A peatland is a type of wetland whose soils consist of Soil organic matter, organic matter from decaying plants, forming layers of peat. Peatlands arise because of incomplete decomposition of organic matter, usually litter from vegetation, du ...

and

tundra In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic ...

, with documented increases in vascular plant

biomass Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...

and decreases in

moss Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...

abundance, particularly the genus

. This moss is critical in bogs for its ability to absorb and retain moisture and nutrients from the atmosphere, and to retard

vascular Vascular can refer to: * blood vessels, the vascular system in animals * 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 ...

plant growth, thus contributing to

carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

is lower than in Europe. Studies in boreal peatlands in

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

have reported a

positive correlation In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statisti ...

between wet N deposition and C accumulation, but it is unclear whether this pattern would continue under higher N deposition levels. With a warmer and drier

, without the effect of N deposition, bog communities in Canada are likely to shift and could become weaker C sinks or even C sources. Ombrotrophic bogs have also been assessed for their uses as archives of atmospheric mercury deposition. This involves studying the solid state distributions of mercury and other metals in the bog to understand postdepositional transport processes and the immobility of deposited trace metals. It was found that mercury (Hg) and

lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

(Pb) are immobile in ombrotrophic peat, indicating that their distribution can be used to determine temporal changes in deposition and suggesting that ombrotrophic bogs can serve as reliable records of historic atmospheric mercury deposition. Historic atmospheric mercury deposition in Arlberg Bog,

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

, increased gradually after the mid-1800s, peaked between 1950 and 1960, and may have declined thereafter.

Preindustrial Pre-industrial society refers to social attributes and forms of political and cultural organization that were prevalent before the advent of the Industrial Revolution, which occurred from 1750 to 1850. ''Pre-industrial'' refers to a time befor ...

deposition levels were estimated to be about 4 μg/m² per year, while recent deposition levels were approximately 19 μg/m² per year. The deposition of mercury in Arlberg Bog appeared to have been influenced by both regional and/or local-scale sources, highlighting the complex nature of atmospheric deposition patterns and the need to consider multiple factors when studying

metal A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated wit ...

deposition in ombrotrophic bogs. However, despite their significance as sources of

fuel A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work (physics), work. The concept was originally applied solely to those materials capable of releasing chem ...

and

horticultural Horticulture (from ) is the art and science of growing fruits, vegetables, flowers, trees, shrubs and ornamental plants. Horticulture is commonly associated with the more professional and technical aspects of plant cultivation on a smaller and mo ...

peat moss, there is still much to uncover about the

ecological Ecology () is the natural science of the relationships among living organisms and their environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere levels. Ecology overlaps with the closely re ...

and biogeochemical processes of ombrotrophic bogs. Chemical analyses of

profiles could shed light on this aspect, but the data collected so far have not been adequate for such analysis. One of the main challenges is the infrequent sample intervals and the lack of

chemical A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combin ...

data on surface peat or sufficient information on

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

conditions. Although some nutrient release occurs in ombrotrophic peat, there is a significant gap in understanding the rate and depth of element release and how

mobility Mobility may refer to: Social sciences and humanities * Economic mobility, ability of individuals or families to improve their economic status * Geographic mobility, the measure of how populations and goods move over time * Mobilities, a conte ...

varies within these ecosystems. Therefore, despite the recognition of their importance, ombrotrophic bogs remain relatively understudied, highlighting the need for further research to fill these knowledge gaps and gain a comprehensive understanding of their ecological processes.

Notes

References

* Charman, D., ''Peatlands and Environmental Change''. John Wiley & Sons, 2002. Pedology {{ecology-stub

See also

Notes

References