[ad_1]

The unusual, prolonged December 2006-January 2007 warmth followed by a sustained cold spell of below normal temperatures and scattered periods of snow from January 16th until the end of February illustrated the resilience of nature because of the opportunity for scientific observation and study it presented. It also demonstrated that certain flowers are capable to end and even survive the stresses associated with prolonged exposure to cold and that certain plants can regenerate buds fast enough to bloom for a second time when Spring's warmth and pollinating insects arrive.

With the unseasonable, protracted warmth due to a weather pattern called persistence, plants such as a few snowdrops, began to blossom in late November and honeybees hung around through January 7th, 2007. Afterwards, despite the month-and-a-half cold spell that also featured single digit readings, robins that usually "migrate south for the winter, then return north for the breeding season March-May" [1] remained put and at least one or two types of flowers remained in bloom each and every day of the winter season (December 21st, 2006-March 20th, 2007) in the New York City metro area. The latter was probably unpreceded since press reports from previous anomalous winters had never mentioned nor monitored the presence of flowers after the periods of unusual warmth had subsided.

While the presence of bees had been documented during warm spells in the winters of 1827-28 and 1931-32, robins during warm spells in the winters of 1772-73 and 1931-32, and flowers during warm spells in the winters of 1777- 78, 1827-28, 1931-32 and 1949-50, the 2006-07 winter was historic in that all three were present at the same time for only the second time, following the precedent setting 1931-32 winter. Bees were around in December, January, and early March, while robins and a couple types of flowers were present through the 2006-07 winter.

During the peak cold period, when the ground froze and / or was covered by snow, robins, which are typically carnivorous, consuming worms for their meal, adapted and subsisted on an herbivorous diet of berries. Bees, on the other hand, vanished until March 3rd, 2007 when a period of pronounced warmth returned.

When the below average temperatures arrived and then lingered for a prolonged period, several flowering plants showed noticeable resilience and recovery practices, two potentially significant characteristics as global warming transforms the climate. As winters become shorter and anomalous warm spells become the norm, these hits will be especially important to enhance their survival when they are lured into early blooms only to have to end several more weeks of winter cold. Since 1971, "winter temperatures in the Northeast have increased by 2.8 degrees [F]" [2] while warm weather has persisted longer, reflecting deeper into December and come earlier, arriving in late February or early March, reducing winter into a 1 ½ to 2 month season instead of the 3 month period of sustained cold characterized by bitter chills and snow it used to be known for.

Although cherry blossoms began blooming on December 19th, 2006 at the Brooklyn Botanic Garden and then elsewhere across the New York metro region, and flowered through January 16th, 2007, they exhibited a typical fragile state that one would expect to find in flowers. When the first arctic air rushed into the region causing temperatures to plunge into the teens, the blossoms already affected by a day of light snow a week earlier, proved to be highly susceptible. They quickly lost color, dried up and died. Adonis flowers were even more sensitive. They lasted only through January 12th, 2007 after succumbing to effects the brief January 8th-9th cold snap that saw a few scattered snow showers, even though temperatures had reclaimed by January 10th.

Other flowers, though, shown greater resilience. Daffodils, which had come into bloom on January 5th, shifted through January 27th, 2007. Some forsythia, which had begun blooming on December 16th, 2007 and Baby's Breath spirea and Winter honeysuckles, which had burst into bloom on January 5th, 2007, survived more than a half month of cold, through February 3rd, 2007. This period included three days in the teens, one single digit reading and a mean temperature of 29 degrees F in New York City.

At the same time, a few partially opened Japanese apricot blossoms survived through February 17th, 2007 after coming to bloom on December 31st, 2006 in spite of 11 additional days of sub-20 readings. Most impressive, although were snowdrops and hellebore, known for blooming in late January or early February that produced flowers on December 24th, 2006 and December 30th, 2006, respectively. Some of these flowers survived the entire winter extending their blooms into April, please 1 months months of below normal cold.

While all of the multigenic exercises (the integrated cohesive metabolism generating induction or activation andression of a multiple number of genes) that enabled these plants to survive the prolonged below average temperatures is not known, several factors may have played a role, sometimes steadily versus fluctuating temperatures, tropisms (slow plant movement in response to a stimuli - temperature and sunlight), and / or even color.

When the cold spell arrived, temperatures plummeted on January 16th from early morning highs in the 50s to the low 20s. Afterwards temperatures remained basically consistent with highs in the upper 20s or low 30s and lows in the mid-to-upper teens and low 20s. This may have been beneficial since studies have shown that "plant cells generally sense and react to rate of temperature change rather than absolute temperature." [3]

With sustained cold in lieu of variable temperatures these plants were able to effectively sense the change in temperature and optimally adjust their metabolic processes - lower water absorption, activation andression of certain genes to maintain a state of homeostasis with RNA and DNA to compensate for the decrease in membrane fluidity and so protect critical cells and tissues - for the conditions without having to make additional adjustments that might have been required to compensate for fluctuations. Had temperatures fluctuated, it is likely that some of these plants would not have been able to attain the optimum metabolic levels required to survive the stresses of the cold, resulting in earlier losses of flowers, especially since structural parts ranged from the ovule to the pistil , and ovary and petals suffered a degree of frost damage under the actual conditions that were presented.

Tropisms, formerly phototropism (movement toward sunlight) in all of the listed plants and both phototropism and thermotropism (temperature induced movement) in hellebore possibly also played a role. While the impact of phototropism was likely minimal for wild rose and Baby's Breath spirea bushes since they did not produce leaves, it was significantly greater for plants such as camellias, snowdrops, and hellebore that did produce leaves to support photosynthesis. The role of thermotropism may have been significant in helping hellebore to survive the prolonged chill. On some of the coldest days, the flowers remained low to the ground that, although imperceptible to the human senses, generated a level of geothermal warmth. Furthermore, where leaves that had fallen from nearby trees during the autumn season were present, hellebore flowers even buried themselves underneath them to shield them against the cold. Yet when there was ample sunlight and radiant warmth, these hellebore blossoms rose and standing erect and away from the ground. The phototropic and thermotropic nature of hellebore was prevalent in flowers at Central Park, New York, NY and The New York Botanical Garden, Bronx, NY.

A third factor that may have played a role in resilience and durability was color. Flowers of darker colors generally succumbed faster (eg camellia and Adonis blossoms) than those of lighter colors (eg hellebore, snowdrops, forsythia, etc.), with the exception of wild roses. When purple hellebore and white hellebore were compared, the latter endured the entire winter while the former succumbed by mid February, providing evidence that absorption and reflection of sunlight, dictated by color and its various shades, is a factor to be considered. As sunlight also regulates a plant's metabolism, it is likely that the greater the level of absorption attained through darker colors, the greater the rate of metabolism and ultimately the susceptibility of the flower to cold and other winter stresses.

While the anomalous 2006-07 winter vividly displayed the tolerance and resilience of some flowers have for cold, it also presented a showcase of the regenerative and recovery hits of several plants. Although cherry blossom trees that had bloomed in December and January had failed to produce new blossoms in the spring, several plants bloomed a second time when warmer weather arrived. Some even produced new buds following the shortened 1--month hibernation period during the January 16th-February 28th sustained cold.

Adonis plants that had flowered in January 2007 at The New York Botanical Garden bloomed again by March 3rd. Witch hazel, viburnum, camellia, and a Japanese apricot tree, all of which had bloomed in early January at The New York Botanical Garden, also bloomed for a second time - March 10th for the witch hazel, March 24th for the viburnum, and March 31st for the latter two. The same held true for Central Park's forsythia that had maintained flowers through February 3rd and bloomed a second time by March 31st.

As these plants bloomed a second time from existing buds that had not opened during the anomalous warm spell and that had survived the prolonged period of cold, they produced significantly fewer flowers than like kind plants that had remained dormant during the unseasonable December 2006-January 2007 warmth.

At the same time though, some plants such as the Adonis, Winter honeysuckle, Baby's Breath spirea, and wild roses, the latter three that had bloomed into February 2007, produced new buds. Correspondingly when they bloomed for a second time - March 10th, March 24th, March 31st, and April 7th, respectively, they produced significant quantities of flowers whose difference was indiscernible from plants that had not bloomed during the anomalous December-January warmth. As these plants generated new buds and blossoms in only half the normal cycle minus the gradual autumn cooling, they illustrated a remarkable regenerative ability.

In conclusion, despite prolonged periods of slowed metabolism generally have serious adverse effects on flowers, the anomalous 2006-07 winter has shown that not every plant or flower will succumb to cold and snow. It has also shown that some flowers and animal species such as bees and robins can adapt with remarkable agility to survive and that some plants have impressive regenerative abilities to recover completely from a false spring followed by sudden and prolonged cold, to produce significant amounts of flowers for consequent pollination, an important step for reproduction and ultimately their long-term survival, when great numbers of insects are prevalent.

Further studies, especially of the genetic makeup of these plants, could provide important clues that will lead to hardier crops geared to withstand sudden cold and other climactic changes. This may be especially critical as global warming impacts the world's ecosystem and quite the food chain that so many species readily upon for their day-to-day survival.

____________

[1] Travis Brady. Life by the Fire and Under the Ice. December 2006. 11 February 2007. http://www.townlink.com/community_web/gnc/gncartrp.htm

[2] Warm Winters Upset Rhythms of Maple Sugar. The New York Times. 3 March 2007. 9 April 2007. [http://infonews.us/us-life/warm-winters-upset-rhythms-of-maple-sugar/print/]

[3] Maggie Smallwood and Dianna J. Bowles. Plants in a cold climate. The Royal Society. 2002. 831.

[ad_2]

Source by William Sutherland

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Enter Captcha Here : *

Reload Image