خزش فصلی
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در پدیدهشناسی (فنولوژی)، خزش فصلی[۱] (به انگلیسی: Season creep) به تغییرهای دیده شده در زمانبندی فصلها اشاره دارد،[۲] مانند نشانههای اولیه بهار[۳] که بهطور گسترده در مناطق معتدل در سراسر نیمکره شمالی دیده شدهاست.[۴][۵] رکوردهای پدیدهشناسی تجزیه و تحلیل شده توسط دانشمندان آب و هوا، روندهای زمانی قابل توجهی را در زمان مشاهده رویدادهای فصلی نشان دادهاست،[۶][۷] از پایان سدهٔ ۲۰ و تا قرن ۲۱ ادامه دارد.[۵][۸] در اروپا، خزش فصلی با فرا رسیدن بهار در یک دوره ۳۰ ساله اخیر تقریباً یک هفته افزایش یافتهاست.[۹][۱۰] مطالعات دیگر میزان خزش فصلی را که توسط فنولوژی گیاه اندازهگیری میشود، در محدوده ۲ تا ۳ روز در دهه در بهار زودتر و ۰٫۳ تا ۱٫۶ روز در هر دهه دیرکرد در پاییز در ۳۰ تا ۸۰ سال گذشته قرار دادهاند.[۱۱]
اثرات خزش فصلی توسط غیردانشمندان نیز مورد توجه قرار گرفتهاست، از جمله باغبانانی که زمان کاشت بهاره خود را افزایش دادهاند،[۱۲] و کاشت انواع گیاهان غیربومی با آب و هوای گرمتر کمتر مقاومتر را آزمایش کردهاند.[۱۳] در حالی که فصل رشد تابستان در حال گسترش است، زمستانها گرمتر و کوتاهتر میشوند و در نتیجه پوشش یخ زمستانی روی پیکرههای آبی کاهش مییابد،[۱۴] یخها زودتر بیرون میآیند،[۱۵] جریان آب زودتر ذوب میشود،[۱۶] و اوجهای سطح دریاچه بهاره زودتر میرسد.[۱۷] برخی از رویدادهای بهاری یا «فنوفازها» متناوب یا غیرقابل دیدن شدهاند. برای مثال، تودههای آبی که زمانی بهطور منظم در اکثر زمستانها یخ میزدند، اکنون کمتر یخ میزنند،[۸][۱۸][۱۹] و پرندگان کوچنده پیشین اکنون در تمام طول سال در برخی مناطق دیده میشوند.[۲۰]
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خزش فصلی ممکن است اثرات ناخوشایند نیز بر گونههای گیاهی داشته باشد. گلدهی زودتر ممکن است پش از فعال شدن گردهافشانهایی مانند زنبورهای عسل اتفاق بیفتد که پیامدهای منفی برای گردهافشانی و تولیدمثل خواهد داشت.[۲۱] زمستانهای کوتاهتر و گرمتر ممکن است دیگر سازگاریهای محیطی از جمله سخت شدن سرد درختان را تحت تأثیر قرار دهد که میتواند سبب آسیب سرمازدگی در زمستانهای شدیدتر شود.[۲۱]
منابع
[ویرایش]- ↑ سازمان برنامه و بودجه کشور (۱۳۹۹). راهنمای مطالعه و اجرای عملیات پایدارسازی زمینلغزشها (جلد اول- مطالعات رفتارسنجی زمینلغزشها). سازمان برنامه و بودجه کشور. ص. https://shaghool٫ir/Files/۸۱۴۰۶۷_Code۰۸۲۹-۱-۹۹۰۹۲۶٫pdf. شابک ضابطه شماره ۱-۸۲۹ مقدار
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را بررسی کنید: invalid character (کمک). - ↑ Maxwell, Kerry (2006-09-18). "Macmillan English Dictionary Word Of The Week Archive - "Christmas creep"". New Words. Macmillan Publishers. Archived from the original on 2007-03-20. Retrieved 2007-12-26.
...season creep, earlier spring weather and seasonal shifts caused by global climate change
- ↑ Maxwell, Kerry (December 2007). "A review of 2007 in twelve words". MED Magazine. Macmillan English Dictionaries. Retrieved 2007-12-23.
It’s a classic case of the newly identified phenomenon of season creep, where Winters are warmer and Spring arrives earlier.
- ↑ Schwartz, M. D.; Ahas, R.; Aasa, A. (2006). "Onset of spring starting earlier across the Northern Hemisphere". Global Change Biology. 12 (2): 343–351. Bibcode:2006GCBio..12..343S. doi:10.1111/j.1365-2486.2005.01097.x.
SI first leaf dates, measuring change in the start of ‘early spring’ (roughly the time of shrub budburst and lawn first greening), are getting earlier in nearly all parts of the Northern Hemisphere. The average rate of change over the 1955–2002 period is approximately -1.2 days per decade.
- ↑ ۵٫۰ ۵٫۱ Cleland, E.E.; Chiariello, N.R.; Loarie, S.R.; Mooney, H.A.; Field, C.B. (2006). "Diverse responses of phenology to global changes in a grassland ecosystem". Proceedings of the National Academy of Sciences. 103 (37): 13740–4. Bibcode:2006PNAS..10313740C. doi:10.1073/pnas.0600815103. PMC 1560087. PMID 16954189.
Shifting plant phenology (i.e. , timing of flowering and other developmental events) in recent decades establishes that species and ecosystems are already responding to global environmental change. Earlier flowering and an extended period of active plant growth across much of the northern hemisphere have been interpreted as responses to warming.
- ↑ McFedries, Paul (August 2006). "Changing Climate, Changing Language". IEEE Spectrum. Retrieved 2007-12-23.
Did spring seem to arrive a bit earlier than usual this year in your part of the world? That wouldn’t be surprising, because we seem to be undergoing season creep: earlier spring weather and other gradual seasonal shifts, particularly those caused by global climate change.
- ↑ Sayre, Carolyn (2006-12-17). "The Year in Buzzwords 2006". TIME. Archived from the original on January 21, 2007. Retrieved 2007-12-26.
SEASON CREEP n. Spring seemed to come early this year--and summer lasted a bit longer. What's to blame? Most scientists say global warming.
- ↑ ۸٫۰ ۸٫۱ Skinner, Victor (2007-02-17). "Area temperatures expected to rise back to 'normal'". Traverse City Record-Eagle. Archived from the original on 28 July 2011. Retrieved 2007-12-27.
...the west arm of Grand Traverse Bay … has only frozen over five times since 1987,.... Between 1851 and 1980, [it] froze at least seven years per decade, … the bay-freezing trend shows "a long-term gradual decline with a significant decline in the past 25 to 35 years. ”
- ↑ Stutz, Bruce (2006-04-21). "Suddenly spring". The Record (Bergen County, NJ). Archived from the original on 2011-05-16. Retrieved 2007-12-23.
In fact, due to global warming, spring across the Northern Hemisphere arrives a week or more earlier than it did 30 years ago, a phenomenon starting to be known as "season creep."
- ↑ "Climate changes shift springtime: A Europe-wide study has provided "conclusive proof" that the seasons are changing, with spring arriving earlier each year, researchers say". Science/Nature. BBC News. 2006-08-25. Retrieved 2007-12-28.
Spring was beginning on average six to eight days earlier than it did 30 years ago, the researchers said.
- ↑ Sherry, R.A.; Zhou, X.; Gu, S.; Arnone Iii, J.A.; Schimel, D.S.; Verburg, P.S.; Wallace, L.L.; Luo, Y. (2007). "Divergence of reproductive phenology under climate warming". Proceedings of the National Academy of Sciences. 104 (1): 198–202. Bibcode:2007PNAS..104..198S. doi:10.1073/pnas.0605642104. PMC 1713188. PMID 17182748.
Phenology is a sensitive biosphere indicator of climate change. Long-term surface data and remote sensing measurements indicate that plant phenology has been advanced by 2–3 days in spring and delayed by 0.3–1.6 days in autumn per decade in the past 30–80 years, resulting in extension of the growing season.
- ↑ Smith, Virginia A. (2007-04-07). "Out on a limb: Gardeners excited by the early warmth — call it "season creep" - are experimenting with earlier planting and new varieties". The Philadelphia Inquirer. Retrieved 2007-12-23.
...earlier springs — an idea known as "season creep" — may or may not be related to long-term warming trends. Yet the reality of year-to-year weather weirdness recently, coupled with the ever-present impulse to outsmart Mother Nature, has prompted more than a few gardeners to shun conventional horticultural wisdom.
- ↑ Williams, Brad (2007-04-08). "Dogwoods to frogs, tulips to snow, Knox shows signs of warming". Knoxville News Sentinel. Retrieved 2007-12-23.
Knoxville is now in hardiness Zone 7, a zone where more southern trees and shrubs flourish. The zone shift can be seen all across the northern half of the state. It effectively means plants that once had difficulty growing here are now finding it easier to thrive, said Lisa Stanley, master gardener at Stanley's Greenhouses
- ↑ Magnuson, J.J.; Robertson, D.M.; Benson, B.J.; Wynne, R.H.; Livingstone, D.M.; Arai, T.; Assel, R.A.; Barry, R.G.; Card, V. (2000). "Historical Trends in Lake and River Ice Cover in the Northern Hemisphere". Science. 289 (5485): 1743–1746. Bibcode:2000Sci...289.1743M. doi:10.1126/science.289.5485.1743. PMID 10976066.
Freeze and breakup dates of ice on lakes and rivers provide consistent evidence of later freezing and earlier breakup around the Northern Hemisphere from 1846 to 1995. Over these 150 years, changes in freeze dates averaged 5.8 days per 100 years later, and changes in breakup dates averaged 6.5 days per 100 years earlier;
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suggested) (help) - ↑ Hodgkins, G.A.; Ii, I.C.J.; Huntington, T.G. (2002). "Historical Changes In Lake Ice-out Dates As Indicators Of Climate Change In New England, 1850--2000" (PDF). International Journal of Climatology. 22 (15): 1819–1827. Bibcode:2002IJCli..22.1819H. doi:10.1002/joc.857. Retrieved 2007-12-28.
Various studies have shown that changes over time in spring ice-out dates can be used as indicators of climate change.... Ice-out dates have become significantly earlier in New England since the 1800s
- ↑ Dybas, Cheryl Lyn (2006-03-20). "Early Spring Disturbing Life on Northern Rivers". The Washington Post. Retrieved 2007-12-26.
Research by [USGS hydrologist Glenn] Hodgkins and USGS scientist Robert Dudley also shows changes in early-spring stream flow across eastern North America from Minnesota to Newfoundland. Rivers are gushing with snow- and ice-melt as much as 10 to 15 days sooner than they did 50 to 90 years ago, based on USGS records.
- ↑ "Early risers". New Scientist. 167 (2241): 21. 2000-06-03. Retrieved 2007-12-27.
North America's Great Lakes are reaching their spring high-water levels a month earlier than they did when records began in 1860. Levels normally rise in the spring as snow melts, but regional temperatures have been rising for the past 90 years, and winter ice cover has been shrinking.
- ↑ Wake, Cameron (2006-12-04). "Climate Change in the Northeast: Past, Present, and Future" (PDF). Climate Change in the Hudson Valley, NY. Archived from the original (PDF) on 7 September 2008. Retrieved 2007-12-27.
A particularly interesting lake ice record comes from Lake Champlain where they record the ice in date.... Of more significance is the fact that the ice has not frozen in the area of observation in 16 of the past 30 years.
- ↑ "Why Less Winter Ice is the Pitts for State". The Detroit Free Press. 2006-04-03. Retrieved 2007-12-23.
Grand Traverse Bay … froze at least seven winters out of every 10; the rate slipped in the 1980s. In the 1990s, the bay froze only three times. So far this decade, once. Observers see that as one more sign of what some call "season creep," or evidence of global warming.
- ↑ "Report warns of global warming increase". Portsmouth Herald. Archived from the original on 17 July 2011. Retrieved 2007-12-27.
...Jan Pendlebury, executive director of the New Hampshire chapter of the National Environmental Trust, said... 'Global warming is forcing changes to the quintessential indicator that spring has arrived: return of the robin. Recent years have documentation that rather than flying south with other feathered friends, many populations of robins are becoming year-round residents, not only in the southern tier of the state, but as far north as Jackson.'
- ↑ ۲۱٫۰ ۲۱٫۱ Chung, Uran; Mack, Liz; Yun, Jin I.; Kim, Soo-Hyung (2011). Harvey, Jeffrey A (ed.). "Predicting the Timing of Cherry Blossoms in Washington, DC and Mid-Atlantic States in Response to Climate Change". PLoS ONE. 6 (11): e27439. Bibcode:2011PLoSO...627439C. doi:10.1371/journal.pone.0027439. PMC 3210174. PMID 22087317.
The expected changes in phenology will have a substantial effect on the reproduction, distribution and productivity of trees as the coincidence of ecosystem processes, such as flowering and the emergence of pollinators, is disrupted. Some plants may also become less resistant to environmental challenges. For example, shorter and warmer winters can reduce the cold hardening of trees, leaving them vulnerable to frost injury.