A polje, also karst polje or karst field, is a large flat plain found in karstic geological regions of the world, with areas usually . The name derives from the Slavic languages and literally means 'field', whereas in English ''polje'' specifically refers to a karst plain or karst field.

In geology

A polje, in geological terminology, is a large, flat-floored depression within karst limestone, whose long axis develops in parallel with major structural trends and can become several miles (tens of kilometers) long. Superficial deposits tend to accumulate along the floor. Drainage may be either by surface watercourses (as an ''open polje'') or by

swallow hole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

s (as a ''closed polje'') or ponors. Usually, the ponors cannot transmit entire flood flows, so many poljes become wet-season lakes. The structure of some poljes is related to the geological structure, but others are purely the result of lateral dissolution and

planation In geology and geomorphology a planation surface is a large-scale surface that is almost flat with the possible exception of some residual hills. The processes that form planation surfaces are labelled collectively planation and are exogenic (chi ...

. The development of poljes is fostered by any blockage in the karst drainage. A polje covers the flatbottomed lands of closed basins which may extend over large areas, up to 1,000 km². The flat floor of a polje may consist of bare limestone, of a nonsoluble formation (as with rolling topography), or of soil. A polje typically shows complex hydrogeological characteristics such as exsurgences, estavelles, swallow holes, and

lost rivers Lost may refer to getting lost, or to: Geography * Lost, Aberdeenshire, a hamlet in Scotland *Lake Okeechobee Scenic Trail, or LOST, a hiking and cycling trail in Florida, US History *Abbreviation of lost work, any work which is known to have bee ...

. In colloquial use, the term "polje" designates flat-bottomed lands which are overgrown or are under cultivation. The Dinaric

Karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

has many poljes. They are mostly distributed in subtropical and tropical latitudes but some also appear in temperate or, rarely, boreal regions. Usually covered with thick sediments, called "terra rossa", they are used extensively for agricultural purposes. Some ''poljes'' of the Dinaric Alps are inundated during the rainy winters and spring seasons as masses of water called ''izvor'' or ''vrelo'' appears at the margins. The water disappears through shafts called ''ponor''. Polje inundado 02

Prominent karst poljes are Livanjsko polje (about 60 km long and 7 km wide), Glamočko Polje, Grahovsko Polje, Drvarsko Polje, Duvanjsko Polje, Kupreška Visoravan ''(Kupres Highlands)'', Popovo Polje, Dabarsko Polje, Nevesinjsko Polje and Gatačko Polje in Bosnia and Herzegovina; Logatec, Planina, and Cerknica Polje in Slovenia; Grahovsko Polje and Nikšićko Polje in Montenegro; Ličko Polje and Krbava in

Lika Lika () is a traditional region of Croatia proper, roughly bound by the Velebit mountain from the southwest and the Plješevica mountain from the northeast. On the north-west end Lika is bounded by Ogulin-Plaški basin, and on the south-east by ...

, Croatia; Odorovsko polje the only karst polje in Serbia. In Portugal, the town of Minde is located in a landscape of intensive karst. In the summer the polje is fertile fields, in winter, in case of heavy rain, a temporary lake. Compare also Lake Copais in Boeotia in Greece.

Etymology

The term is synonymous with ''interior valley''. The word ''polje'' () itself is of Slavic origin (best known as the root for the country Poland, ''Polska'', from the Polish word ''pole'' 'field'). English borrowed ''polje'' from Slovene"Glossary of Cave and Karst Terms" (letter "P"), Speliogenesis.info, 2009, webpage
Spelio-gloss-P
or Serbo-Croatian (, ). The equivalent in neighbouring

Macedonian Macedonian most often refers to someone or something from or related to Macedonia. Macedonian(s) may specifically refer to: People Modern * Macedonians (ethnic group), a nation and a South Slavic ethnic group primarily associated with North M ...

and Bulgarian is ''pole'' (поле), and in Russian it is ''polye'' (поле). As a borrowing, apart from English it can be found in a number of languages including:

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

, German, Greek, Italian, Spanish and

Turkish Turkish may refer to: *a Turkic language spoken by the Turks * of or about Turkey ** Turkish language *** Turkish alphabet ** Turkish people, a Turkic ethnic group and nation *** Turkish citizen, a citizen of Turkey *** Turkish communities and mi ...

(which uses ''polye'').

Notes

{{Authority control . Karst formations Landforms Plains Physical geography Slavic words and phrases Dinaric karst formations Dinaric Alps