دراسة الأحداث البيولوجية: الفرق بين النسختين

{{ترجمة}}

 

نظراً لأن العديد من هذه الظواهر حساسة جداً لتغيرات [[مناخ|المناخ]]، خصوصاً درجات الحرارة، فقد تكون السجلات الفينولوجية وثائق مفيدة للحرارة في علم المناخ التاريخي، خاصة لدراسة [[تغير المناخ]] و[[احترار عالمي|الاحترار العالمي]]. على سبيل المثال، تستخدم سجلات حصاد العنب في أوروبا لإعادة بناء سجلات درجات الحرارة الموسمية المتزايدة في الصيف حتى 500 سنة خلت<ref name=Meier2007a>.

{{Cite journal

The concept of [[Growing-degree day]] contributes to our understanding of phenology.

 

Observations of phenological events have provided indications of the progress of the natural calendar since ancient agricultural times. Many cultures have traditional phenological proverbs and sayings which indicate a time for action: "When the sloe tree is white as a sheet, sow your barley whether it be dry or wet" or attempt to forecast future climate: "If oak's before ash, you're in for a splash. If ash before oak, you're in for a soak". But the indications can be pretty unreliable, as an alternative version of the rhyme shows: "If the oak is out before the [[مران عالي]], 'Twill be a summer of wet and splash; If the ash is out before the oak,'Twill be a summer of fire and smoke." Theoretically, though, these are not mutually exclusive, as one forecasts immediate conditions and one forecasts future conditions.

 

In Japan and China the time of blossoming of cherry and peach trees is associated with ancient festivals and some of these dates can be traced back to the eighth century. Such historical records may, in principle, be capable of providing estimates of climate at dates before instrumental records became available. For example, records of the harvest dates of the [[pinot noir]] [[عنب]] in [[منطقة بورجندي]] have been used in an attempt to reconstruct spring–summer temperatures from 1370 to 2003;<ref name=Chuine>{{Cite journal| last1 = Chuine | first1 = I. | last2 = Yiou | first2 = P. | last3 = Viovy | first3 = N. | last4 = Seguin | first4 = B. | last5 = Daux | first5 = V. | last6 = Le Roy | first6 = Ladurie | year = 2004 | title = Grape ripening as a past climate indicator | url = http://www.cefe.cnrs.fr/fe/pdf/2004_Nature_432_289_290.pdf | format = PDF | journal = Nature | volume = 432 | issue = 7015| pages = 289–290 | doi = 10.1038/432289a | pmid = 15549085 |bibcode = 2004Natur.432..289C |archiveurl=http://web.archive.org/web/20060516044139/http://www.cefe.cnrs.fr/fe/pdf/2004_Nature_432_289_290.pdf|archivedate=2006-05-16}}</ref><ref name=Keenan2007>{{Cite journal| last1 = Keenan | first1 = D.J. | year = 2007 | title = Grape harvest dates are poor indicators of summer warmth | url = http://www.informath.org/pubs/TAC06a.pdf | format = PDF | journal = Theoretical and Applied Climatology | volume = 87 | issue = | pages = 255–256 | doi = 10.1007/s00704-006-0197-9 |bibcode = 2007ThApC..87..255K}}</ref> the reconstructed values during 1787–2000 have a correlation with Paris instrumental data of about 0.75.

 

[[Robert Marsham]] is the founding father of modern phenological recording. Marsham was a wealthy landowner who kept systematic records of "Indications of spring" on his estate at [[Stratton Strawless]], [[نورفولك]], from 1736. These were in the form of dates of the first occurrence of events such as flowering, bud burst, emergence or flight of an insect. Consistent records of the same events or "phenophases" were maintained by generations of the same family over unprecedentedly long periods of time, eventually ending with the death of Mary Marsham in 1958, so that trends can be observed and related to long-term climate records. The data show significant variation in dates which broadly correspond with warm and cold years. Between 1850 and 1950 a long-term trend of gradual climate warming is observable, and during this same period the Marsham record of oak leafing dates tended to become earlier.<ref name="Sparks & Carey">{{Cite journal| last1 = Sparks | first1 = T.H. | last2 = Carey | first2 = P.D. | year = 1995 | title = The responses of species to climate over two centuries: an analysis of the Marsham phenological record, 1736-1947 | url = | journal = Journal of Ecology | volume = 83 | issue = 2| pages = 321–329 | doi = 10.2307/2261570}}</ref>

 

William Felker has studied phenology in [[أوهايو]], USA since 1973 and now publishes "Poor Will's Almanack", a phenological almanac for farmers (not to be confused with a late 18th century almanac by the same name).

 

Recent technological advances in studying the earth from space have resulted in a new field of phenological research that is concerned with observing the phenology of whole [[نظام بيئي]]s and stands of [[غطاء نباتي]] on a global scale using proxy approaches. These methods complement the traditional phenological methods which recorded the first occurrences of individual species and phenophases.

 

However, these phenological parameters are only an approximation of the true biological growth stages. This is mainly due to the limitation of current space based remote sensing, especially the spatial resolution, and the nature of vegetation index. A pixel in an image does not contain a pure target (like a tree, a shrub, etc.) but contains a mixture of whatever intersected the sensor's field of view.

 

* [[Citizen science]]

* [[Nature Detectives]]

* [[دورة حياة (أحياء)]]

 

{{مراجع}}

 

* [http://www.pwrc.usgs.gov/bpp/ North American Bird Phenology Program] Citizen science program to digitize bird phenology records

* [http://neoninc.org/budburst/ Project Budburst] Citizen Science for Plant Phenology in the USA

 

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