دراسة الأحداث البيولوجية: الفرق بين النسختين

تم إضافة 462 بايت ، ‏ قبل 9 أشهر
بوت:الإبلاغ عن رابط معطوب أو مؤرشف V3.3
(بوت:أضاف قالب:بطاقة تخصص.)
(بوت:الإبلاغ عن رابط معطوب أو مؤرشف V3.3)
''The Phenological Reports'' ended suddenly in 1948 after 58 years, and Britain was without a national recording scheme for almost 50 years, just at a time when climate change was becoming evident. During this period, important contributions were made by individual dedicated observers. The naturalist and author [[Richard Fitter]] recorded the First Flowering Date (FFD) of 557 species of British flowering plants in Oxfordshire between about 1954 and 1990. Writing in [[ساينس]] in 2002, Richard Fitter and his son [[Alistair Fitter]] found that "the average FFD of 385 British plant species has advanced by 4.5 days during the past decade compared with the previous four decades."<ref name=Fitter2002>{{Cite journal| الأخير1 = Fitter | الأول1 = A.H. | الأخير2 = Fitter | الأول2 = R.S.R. | author-separator =, | author-name-separator= | السنة = 2002 | العنوان = Rapid changes in flowering time in British plants | المسار = | journal = Science | volume = 296 | issue = 5573| الصفحات = 1689–1691 | doi = 10.1126/science.1071617 | pmid = 12040195 |bibcode = 2002Sci...296.1689F}}</ref><ref>{{Cite journal|المسار=http://eprints.whiterose.ac.uk/201/1/fitterah4.pdf |العنوان=Rapid Changes in Flowering Time in British Plants |الناشر=SCIENCE |volume=296 |التاريخ=31 May 2002 |تاريخ الوصول=2010-05-25|مسار الأرشيف=http://web.archive.org/web/20081217053707/http://eprints.whiterose.ac.uk/201/1/fitterah4.pdf|تاريخ الأرشيف=2008-12-17}}</ref> They note that FFD is sensitive to temperature, as is generally agreed, that "150 to 200 species may be flowering on average 15 days earlier in Britain now than in the very recent past" and that these earlier FFDs will have "profound ecosystem and evolutionary consequences".
 
In the last decade, national recording in Britain has been resumed by the UK Phenology network [http://www.naturescalendar.org.uk], run by [[Woodland Trust]] and the [[Centre for Ecology and Hydrology]] and the BBC Springwatch survey.<ref>[http://web.archive.org/web/20070209113737/http://www.bbc.co.uk/nature/animals/wildbritain/springwatch/survey.shtml BBC - Science & Nature - UK Wildlife - Springwatch survey<!-- Bot generated title -->]</ref> There is a USA National Phenology Network [http://www.usanpn.org/] in which both professional scientists and lay recorders participate, a European Phenology Network that has monitoring, research and educational remits<ref>{{مرجع ويب|المسار=http://www.dow.wau.nl/msa/epn/index.asp |العنوان=European Phenology Network |الناشر=Web.archive.org |التاريخ= |تاريخ الوصول=2010-05-25 |مسار الأرشيف = http://web.archive.org/web/20071222031041/http://www.dow.wau.nl/msa/epn/index.asp |تاريخ الأرشيف = 2007-12-22}}</ref> and many other countries such as Canada (Alberta Plantwatch [http://plantwatch.fanweb.ca/] and Saskatchewan PlantWatch<ref>[http://web.archive.org/web/20080330084910/http://www.naturesask.ca/education_plantwatch.php Nature Saskatchewan : PlantWatch<!-- Bot generated title -->]</ref>), China and Australia<ref>{{مرجع ويب|المسار=http://www.climatewatch.org.au|العنوان=ClimateWatch|الناشر=EarthWatch Institute Australia|تاريخ الوصول=28 August 2013| مسار الأرشيف = https://web.archive.org/web/20190506113114/http://www.climatewatch.org.au/ | تاريخ الأرشيف = 6 مايو 2019 }}</ref><ref>[http://www.bio.mq.edu.au/dept/centres/comparative/BioWatch/BioWatch.htm BioWatch Home<!-- Bot generated title -->]{{وصلة مكسورة|تاريخ=أغسطس 2013}} {{وصلة مكسورة|date= أغسطس 2017 |bot=JarBot}} {{Webarchive|url=http://web.archive.org/web/20120722113242/http://bio.mq.edu.au/dept/centres/comparative/BioWatch/BioWatch.htm |date=22 يوليو 2012}}</ref> have phenological programs.
 
In eastern North America, [[روزنامة]] are traditionally used for information on action phenology (in agriculture), taking into account the astronomical positions at the time.
The evolution of the vegetation index through time, depicted by the graph above, exhibits a strong [[ارتباط (إحصاء)]] with the typical green vegetation growth stages (emergence, vigor/growth, maturity, and harvest/senescence). These temporal curves are analyzed to extract useful parameters about the vegetation growing season (start of season, end of season, length of [[موسم زراعة]], etc.). Other growing season [[وسيط (رياضيات)]]s could potentially be extracted, and global maps of any of these growing season parameters could then be constructed and used in all sorts of [[تغير المناخ]] studies.
 
A noteworthy example of the use of [[استشعار عن بعد]] based phenology is the work of Ranga Myneni<ref>[http://cybele.bu.edu/people/rmyneni.html Welcome to the Climate and Vegetation Research Group, Boston University<!-- Bot generated title -->] {{Webarchive|url=http://web.archive.org/web/20170621100232/http://cybele.bu.edu:80/people/rmyneni.html |date=21 يونيو 2017}}</ref> from [[جامعة بوسطن]]. This work<ref name=Myeni>{{Cite journal| الأخير1 = Myneni | الأول1 = RB | الأخير2 = Keeling | الأول2 = CD | الأخير3 = Tucker | الأول3 = CJ | الأخير4 = Asrar | الأول4 = G | الأخير5 = Nemani | الأول5 = RR | السنة = 1997 | العنوان = Increased plant growth in the northern high latitudes from 1981 to 1991 | المسار = | journal = Nature | volume = 386 | issue =6626 | الصفحة = 698 |doi=10.1038/386698a0|bibcode = 1997Natur.386..698M}}</ref><ref>[http://www.nature.com/nature/journal/v386/n6626/abs/386698a0.html Increased plant growth in the northern high latitudes from 1981 to 1991<!-- Bot generated title -->] {{Webarchive|url=http://web.archive.org/web/20170513224237/http://www.nature.com:80/nature/journal/v386/n6626/abs/386698a0.html |date=13 مايو 2017}}</ref> showed an apparent increase in vegetation productivity that most likely resulted from the increase in temperature and lengthening of the growing season in the [[تايغا]].<ref>[http://web.archive.org/web/20070407143112/http://cliveg.bu.edu/people/rmyneni/portal.cgi.html ISI Web of Knowledge [v3.0&#93;<!-- Bot generated title -->]</ref> Another example based on the [[MODIS]] enhanced vegetation index ([[EVI]]) reported by Alfredo Huete<ref>[http://tbrs.arizona.edu/cdrom/People/WhosWho.html Tbrs, Modis Vi Cd-Rom<!-- Bot generated title -->] {{Webarchive|url=https://web.archive.org/web/20060915100025/http://tbrs.arizona.edu:80/cdrom/People/WhosWho.html |date=15 سبتمبر 2006}}</ref> at [[جامعة أريزونا]] and colleagues showed that the [[غابات الأمازون]], as opposed to the long held view of a monotonous growing season or growth only during the wet rainy season, does in fact exhibit growth spurts during the dry season.<ref name=Huete>{{Cite journal| journal = Geophysical Research Letters |volume=33 |الصفحات= L06405 | المسار=http://ecocast.arc.nasa.gov/pubs/pdfs/2006/Huete_GRL_2006.pdf | doi=10.1029/2005GL025583 | العنوان = Amazon rainforests green-up with sunlight in dry season | السنة = 2006 | الأخير1 = Huete | الأول1 = Alfredo R. | الأخير2 = Didan | الأول2 = Kamel | الأخير3 = Shimabukuro | الأول3 = Yosio E. | الأخير4 = Ratana | الأول4 = Piyachat | الأخير5 = Saleska | الأول5 = Scott R. | last6 = Hutyra | first6 = Lucy R. | last7 = Yang | first7 = Wenze | last8 = Nemani | first8 = Ramakrishna R. | last9 = Myneni | first9 = Ranga | issue = 6 |bibcode = 2006GeoRL..33.6405H}}</ref><ref>{{مرجع ويب|المسار=http://earthobservatory.nasa.gov/Features/AmazonEVI/|العنوان=Defying Dry: Amazon Greener in Dry Season than Wet|الأخير=Lindsey|الأول=Rebecca|المؤلفين المشاركين=Robert Simmon|التاريخ=June 30, 2006|العمل=[[The Earth Observatory]]|الناشر=EOS Project Science Office, [[مركز جودارد للطيران الفضائي]]|تاريخ الوصول=29 August 2013| مسار الأرشيف = https://web.archive.org/web/20170503203232/https://earthobservatory.nasa.gov/Features/AmazonEVI/ | تاريخ الأرشيف = 3 مايو 2017 }}</ref>
 
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.