Why Leaves Change Color (Photosynthesis) - Texas Parks and Wildlife [Official]




Uploaded by TexasParksWildlife on 21.10.2009

Transcript:
IT HAPPENS EVERY YEAR.
AS SURELY AS THE BIRDS TAKE FLIGHT ACROSS THE SOUTHERN SKIES
THE LEAVES BEGIN THEIR NOVEMBER METAMORPHOSES
FROM GREEN TO AN ARRAY OF THE SPECTRUM.
THE 2 BEST KNOWN SPOTS IN TEXAS TO SEE SUCH BEAUTY
ARE McKITTRICK CANYON IN THE GUADALUPE MTNS. NATIONAL PARK
AND LOST MAPLES STATE NATURAL AREA.
[music]
THIS IS WHAT THE CELLS OF A GREEN LIVING LEAF LOOK LIKE
UNDER A MICROSCOPE.
THE GREEN MOVING PARTS CONTAIN CHLORPHYLL
AND IT'S HERE THAT THE PROCESS OF PHOTOSYNTHESIS
TAKES PLACE.
USING ENERGY FROM THE SUN, THE PROCESS OF PHOTOSYNTHESIS
CREATES SUGARS AND STARCHES THAT FEED THE PLANT.
AS THE TREE PREPARES FOR WINTER,
VALUABLE MINERALS IN ITS LEAVES ARE BROKEN DOWN
AND SHIPPED OFF TO THE TRUNK OR ROOTS FOR STORAGE.
VISIBLY THE MOST OBVIOUS CHANGE IS THE BREAKDOWN
OF THE GREEN CHLORPHYLL.
WITH THE GREEN PIGMENT GONE, OTHER PIGMENTS ALREADY PRESENT
IN THE LEAVES BECOME VISIBLE
GIVING US THE FAMILIAR COLORS OF AUTUMN.
SOME YEARS ARE MORE COLORFUL THAN OTHERS
LARGELY DUE TO 3 CRITICAL FACTORS:
TEMPERATURE, RAINFALL AND SUNSHINE.
USUALLY, HOT, DRY AND CLOUDY WEATHER WILL RESULT
IN A DULL COLORED FALL SEASON WITH MOST LEAVES TURNING BROWN.
COOL, WET AND SUNNY WEATHER, ON THE OTHER HAND,
TENDS TO PRODUCE MORE REDDISH COLORED LEAVES,
GIVING THE AUTUMN TREES A SPECTACULAR ARRAY OF COLORS.
[music]
AND SO THIS PALETTE OF CHANGE GOES ON FROM YEAR TO YEAR.
IT'S NATURE'S WAY OF TAKING A BREAK,
RESTING UP FOR THE SPRING.
BUT FOR ALL THE SCIENCE AND UNDERSTANDING,
THE BEAUTY OF NATURE'S PAINTINGS IS PURE MAGIC.