Английская Википедия:Hectare
Шаблон:Short description Шаблон:Infobox unit
The hectare (Шаблон:IPAc-en; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), that is, 10,000 square meters (10,000 m2), and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is about Шаблон:Convert and one hectare contains about Шаблон:Convert.
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 Шаблон:Frac km2 (10,000 square metres). When the metric system was further rationalised in 1960, resulting in the International System of Units (Шаблон:Tooltip), 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
Unit | SI |
---|---|
1 ca | 1 m2 |
1 a | 100 m2 |
1 ha | 10,000 m2 |
100 ha | 1,000,000 m2 1 km2 |
non-SI comparisons | |
non-SI | metric |
0.3861 sq mi | 1 km2 |
2.471 acre | 1 ha |
107,639 sq ft | 1 ha |
1 sq mi | 259.0 ha |
1 acre | 0.4047 ha |
The hectare (Шаблон:IPAc-en[2]), although not a unit of SI, is the only named unit of area that is accepted for use with SI units.[3] The name was coined in French, from the Latin Шаблон:Lang.[4] 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,[5] and it is the legal unit of measure in domains concerned with land ownership, planning, and management, including law (land deeds), agriculture, forestry, and town planning throughout the European Union[6] and Australia (since 1970).[7][8] However, the United Kingdom,[9] the United States, Myanmar (Burma),[10][11] and to some extent Canada, use the acre instead of the hectare for measuring surface or land area.Шаблон:Citation needed
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.Шаблон:Citation needed Others, such as South Africa, published conversion factors which were to be used particularly "when preparing consolidation diagrams by compilation".[12]
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:[13]
- Jerib (Шаблон:Lang-fa) in Iran
- Djerib (Шаблон:Lang-tr) in Turkey[14]
- Gongqing (Шаблон:Zh) in China
- Manzana in Argentina
- Bunder in the Netherlands (until 1937)[15][16]
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:[17]
- The metre for length
- The are (100 m2) for area [of land]
- The stère (1 m3) for volume of stacked firewood[18]
- 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 (Шаблон:Tooltip) makes no mention of the are in the 2019 edition of the SI brochure, but classifies the hectare as a "Non-SI unit accepted for use with the International System of Units".[19]
In 1972, the European Economic Community (EEC) passed directive 71/354/EEC,[20] 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 (dma, sometimes seen in cadastre area evaluation of real estate plots) is Шаблон:Frac are or one square decimetre.[21] Such usage of a double prefix is non-standard. The decimilliare is roughly a four-inch-by-four-inch square.
Centiare
The centiare is one square metre.[22][23]
Deciare
The deciare (rarely used) is ten square metres.[24]
Шаблон:AnchorAre
Шаблон:Redirect The are (Шаблон:IPAc-en[25] or Шаблон:IPAc-en[26]) is a unit of area, equal to 100 square metres (Шаблон:Nowrap), 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).[27] 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 are is called Шаблон:Lang (Шаблон:Lang-ru: 'a hundred', i.e. 100 m2 or Шаблон:Frac hectare). It is used to describe the size of suburban dacha or allotment garden plots or small city parks where the hectare would be too large. Many Russian dachas are 6 ares in size (in Russian, Шаблон:Lang).
Decare
The decare or dekare (Шаблон:IPAc-en) is derived from deca and are, and is equal to 10 ares or 1000 square metres. It is used in Norway[28] and in the former Ottoman areas of the Middle East and Bulgaria[29] as a measure of land area. Instead of the name "decare", the names of traditional land measures are usually used, redefined as one decare:
- Шаблон:Lang in Greece[30]
- Шаблон:Lang in the Balkans, Israel, Palestine, Jordan, Lebanon, Syria, and Turkey[31]
- Шаблон:Lang is used for decare in Norway, from the old measure of about the same area.
Conversions
Unit name | Symbol | Multiple of preceding unit |
Fraction of succeeding unit |
SI equivalents | British imperial/United States customary equivalents |
---|---|---|---|---|---|
centiare | ca | 0.1 da | Шаблон:Val | Шаблон:Convert | |
deciare | da | 10 ca | 0.1 a | Шаблон:Val | Шаблон:Convert |
are | a[32] | 10 da | 0.1 daa | Шаблон:Val | Шаблон:Convert |
decare | daa | 10 a | 0.1 ha | Шаблон:Val | Шаблон:Convert |
hectare | ha[5] | 10 daa | 0.01 km2 | Шаблон:Val | Шаблон:Convert |
square kilometre | Шаблон:Val | 100 ha | Шаблон:Val | Шаблон:Convert |
The most commonly used units are in bold.
One hectare is also equivalent to:
- 1 square hectometre
- 1.008 Шаблон:Lang (Japan)
- 2.381 Шаблон:Lang (Egypt)
- 6.25 Шаблон:Lang (Thailand)
- 10 Шаблон:Lang or Шаблон:Lang (Middle East)[33]
- 10 Шаблон:Lang (Greece)
- 15 Шаблон:Lang or 0.15 Шаблон:Lang[34]
Unicode
The Unicode character Шаблон:Unichar, in the CJK Compatibility block, is intended for compatibility with pre-existing East Asian character codes.[35] It is not intended for use in alphabetic contexts.
See also
References
External links
Шаблон:Commons Шаблон:EB1911 Poster Шаблон:Wiktionary
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Citation Chapter 5.
- ↑ Oxford English Dictionary, 1st edition s.v.
- ↑ 5,0 5,1 Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Britannica.com, unit of measurement, accessed 30 October 2009
- ↑ Шаблон:Cite EB1911
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite book
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite book
- ↑ Шаблон:Cite dictionary
- ↑ Шаблон:Cite dictionary
- ↑ Шаблон:Cite dictionary
- ↑ Шаблон:Cite webШаблон:Dead linkШаблон:Cbignore
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web
- ↑ Λεξικό της κοινής Νεοελληνικής (Dictionary of Modern Greek), Ινστιτούτο Νεοελληνικών Σπουδών, Θεσσαλονίκη, 1998. Шаблон:ISBN
- ↑ Шаблон:Cite book
- ↑ Шаблон:Cite book
- ↑ Шаблон:Cite book
- ↑ Шаблон:Cite web
- ↑ Шаблон:Cite web