HOME

TheInfoList



OR:

The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100- metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is about and one hectare contains about . In 1795, when the metric system was introduced, the ''are'' was defined as 100 square metres, or one square decametre, and the hectare (" hecto-" + "are") was thus 100 ''ares'' or  km2 (10,000 square metres). When the metric system was further rationalised in 1960, resulting in the International System of Units (), the ''are'' was not included as a recognised unit. The hectare, however, remains as a non-SI unit accepted for use with the SI and whose use is "expected to continue indefinitely". Though the dekare/decare daa (1,000 m2) and are (100 m2) are not officially "accepted for use", they are still used in some contexts.


Description

The hectare (), although not a unit of SI, is the only named unit of area that is accepted for use with SI units. Chapter 5. The name was coined in French, from the Latin ''ārea''. In practice the hectare is fully derived from the SI, being equivalent to a square hectometre. It is widely used throughout the world for the measurement of large areas of land, and it is the legal unit of measure in domains concerned with land ownership, planning, and
management Management (or managing) is the administration of an organization, whether it is a business, a nonprofit organization, or a government body. It is the art and science of managing resources of the business. Management includes the activitie ...
, including law ( land deeds), agriculture, forestry, and town planning throughout the
European Union The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are located primarily in Europe, Europe. The union has a total area of ...
and
Australia Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by ...
(since 1970). However, the United Kingdom, United States, Burma, and to some extent Canada use the acre instead. Some countries that underwent a general conversion from traditional measurements to metric measurements (e.g. Canada) required a resurvey when units of measure in legal descriptions relating to land were converted to metric units. Others, such as South Africa, published conversion factors which were to be used particularly "when preparing consolidation diagrams by compilation". In many countries, metrification redefined or clarified existing measures in terms of metric units. The following legacy units of area have been redefined as being equal to one hectare: *'' Jerib'' ( fa, جریب) in
Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
*'' Djerib'' ( tr, cerip) in
Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula ...
*''Gongqing'' () in
China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...
*'' Manzana'' in
Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the List of South American countries by area, second-largest ...
*'' Bunder'' in the
Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...
(until 1937)


History

The metric system of measurement was first given a legal basis in 1795 by the French Revolutionary government. The law of 18 Germinal, Year III (7 April 1795) defined five units of measure: *The :metre for length *The
are Are commonly refers to: * Are (unit), a unit of area equal to 100 m2 Are, ARE or Åre may also refer to: Places * Åre, a locality in Sweden * Åre Municipality, a municipality in Sweden ** Åre ski resort in Sweden * Are Parish, a munici ...
(100 m2) for area
f land F, or f, is the sixth letter in the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''ef'' (pronounced ), and the plural is ''efs''. Hist ...
*The stère (1 m3) for volume of stacked firewood *The :litre (1 dm3) for volumes of liquid *The gram for mass In 1960, when the metric system was updated as the International System of Units (SI), the ''are'' did not receive international recognition. The International Committee for Weights and Measures () makes no mention of the ''are'' in the current (2006) definition of the SI, but classifies the hectare as a "Non-SI unit accepted for use with the International System of Units". In 1972, the European Economic Community (EEC) passed directive 71/354/EEC, which catalogued the units of measure that might be used within the Community. The units that were catalogued replicated the recommendations of the CGPM, supplemented by a few other units including the ''are'' (and implicitly the ''hectare'') whose use was limited to the measurement of land.


Unit family

The names ''centiare'', ''deciare'', ''decare'' and ''hectare'' are derived by adding the standard metric prefixes to the original base unit of area, the ''are''.


Decimilliare

The decimilliare (sometimes seen in cadastre area evaluation of real estate plots) is are or one square decimetre.


Centiare

The centiare is one square metre.


Deciare

The deciare (rarely used) is ten square metres.


Are

The are ( or ) is a unit of area, equal to 100 square metres (), used for measuring land area. It was defined by older forms of the metric system, but is now outside the modern International System of Units (SI). It is still commonly used in speech to measure real estate, in particular in Indonesia, India, and in various European countries. In Russian and some other languages of the former
Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...
, the ''are'' is called (russian: link=no, сотка: 'a hundred', i.e. 100 m2 or hectare). It is used to describe the size of suburban dacha or
allotment garden An allotment (British English), or in North America, a community garden, is a plot of land made available for individual, non-commercial gardening or growing food plants, so forming a kitchen garden away from the residence of the user. Such plot ...
plots or small city parks where the hectare would be too large. Many Russian dachas are 6 ares in size (in Russian, ).


Decare

The decare or dekare () is derived from '' deca'' and ''are'', and is equal to 10 ares or 1000 square metres. It is used in
Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of ...
and in the former Ottoman areas of the
Middle East The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
and
Bulgaria Bulgaria (; bg, България, Bǎlgariya), officially the Republic of Bulgaria,, ) is a country in Southeast Europe. It is situated on the eastern flank of the Balkans, and is bordered by Romania to the north, Serbia and North Macedo ...
as a measure of land area. Instead of the name "decare", the names of traditional land measures are usually used, redefined as one decare: * in
Greece Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders wi ...
* in the
Balkans The Balkans ( ), also known as the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throughout the who ...
,
Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
, Palestine, Jordan, Lebanon,
Syria Syria ( ar, سُورِيَا or سُورِيَة, translit=Sūriyā), officially the Syrian Arab Republic ( ar, الجمهورية العربية السورية, al-Jumhūrīyah al-ʻArabīyah as-Sūrīyah), is a Western Asian country loc ...
and
Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a transcontinental country located mainly on the Anatolian Peninsula in Western Asia, with a small portion on the Balkan Peninsula ...
* is used for decare in Norway, from the old measure of about the same area.


Conversions

The most commonly used units are in bold. One hectare is also equivalent to: * 1 square hectometre * 15 or 0.15 qǐng * 10 dunam or dönüm (Middle East) * 10 stremmata (Greece) * 6.25 rai (
Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...
) * approximately 1.008 chō (
Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...
) * approximately 2.381 feddan (
Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a List of transcontinental countries, transcontinental country spanning the North Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via a land bridg ...
)


See also

* Conversion of units * Hectometre * Order of magnitude


References


External links


Official SI website: Table 6. Non-SI units accepted for use with the International System of Units
{{Use dmy dates, date=June 2016 Units of area Non-SI metric units