温室效應是否會令海龜多數生女?

溫度對海龜的性別有決定性的影響，溫度較高會孵出較多雌性，並且溫室效應也會使全球變暖

綠海龜的一生

每年六月至十月為綠海龜的繁殖季節。在繁殖季節，綠海龜從數千里以外的棲息地迴游到出生地附近的淺海區交配。母龜會在晚上爬上沙灘，選擇合適的地點挖洞作巢，產下海龜蛋並以沙覆蓋著，然後回到大海中。

海龜蛋在巢中會自然地孵化，通常兩個月左右便會孵出小海龜。溫度對海龜的性別有決定性的影響，溫度較高會孵出較多雌性，反之則會孵出較多雄性的。初生的小海龜只有五厘米長，它們會在陰涼的晚上傾巢而出，一起努力地奔向大海，然後依附在大幅漂浮的海草上隨水漂流。小海龜大約一年後便會游到淺海的棲息地生活。

由於香港的環境不斷改變，近年來已很少發現海龜的蹤跡，因此大家更應珍惜及愛護本港現存的海龜產卵地。若海龜受到干擾而不能在南丫島繼續繁殖，在這一代的成龜死亡後，這種稀有的動物將會在本港消失。http://hk.geocities.com/hawkteamclt/newinformationgreenturtles.htm

溫室效應’增強後的影響
i) 氣候轉變：‘全球變暖’




圖片參考：http://www.hko.gov.hk/wxinfo/climat/greenhs/warming.gif
溫室氣體濃度的增加會減少紅外線輻射放射到太空外，地球的氣候因此需要轉變來使吸取和釋放輻射的份量達至新的平衡。 這轉變可包括‘全球性’的地球表面及大氣低層變暖，因為這樣可以將過剩的輻射排放出外。雖然如此，地球表面溫度的少許 上升可能會引發其他的變動，例如：大氣層雲量及環流的轉變。當中某些轉變可使地面變暖加劇(正反饋)，某些則可令變暖過 程減慢(負反饋)。
利用複雜的氣候模式，‘政府間氣候變化專門委員會’在第三份評估報告估計全球的地面平均氣溫會在2100年上升1.4至5.8度。這預計已考慮到大氣 層中懸浮粒子傾於對地球氣候降溫的效應與及海洋吸收熱能的作用 (海洋有較大的熱容量)。但是，還有很多未確定的因素會影響 這個推算結果，例如：未來溫室氣體排放量的預計、對氣候轉變的各種反饋過程和海洋吸熱的幅度等等。http://www.hko.gov.hk/wxinfo/climat/greenhs/c_grnhse.htm

係！
溫度高，令海龜蛋嘅孵化時間縮短，同埋雌性海龜嘅出生率增加．

Ecology and Life History of Sea Turtles
Sea turtles have an extraordinary sense of time and location. They are highly sensitive to the Earth's magnetic field and use it to navigate. They can live up to 189 years. The fact that most species return to nest at the locations where they were born seems to indicate an imprint of that location's magnetic features. The Ridley turtles are especially peculiar because instead of nesting individually like the other species, they come ashore in one mass arrival known as an "arribada" (arrival). With the Kemp's Ridley this occurs during the day and on only one beach in the entire world. Their numbers used to range in the thousands but due to the effects of extensive egg poaching and hunting in previous years the numbers are now in the hundreds.
After about 30 years of maturing, adult female sea turtles return to the land to nest at night, usually on the same beach from which they hatched. This can take place every two to four years in maturity. They make from four to seven nests per nesting season. They dig a hole with their hind flippers and lay from 70 to 190 eggs in it (depending on the species) before covering it up and returning to the ocean. Some of the eggs are unfertilized 'dummy eggs' and the rest contain young turtles. Incubation takes about 2 months. The length of incubation and the gender of the hatchling depends on the temperature of the sand. Darker sands maintain higher temperatures, decreasing incubation time and increasing the frequency of female hatchlings. When the eggs hatch, these baby turtles dig their way out and seek the ocean. Only a very small proportion of them (usually 1%) will be successful, as many predators wait to eat the steady stream of new hatched turtles (since many sea turtles lay eggs en masse, the eggs also hatch en masse).
The hatchlings then proceed into the open ocean, borne on oceanic currents that they often have no control over. While in the open ocean, it used to be the case that what happened to sea turtle young during this stage in their lives was unknown. However in 1987, it was discovered that the young of Chelonia mydas and Caretta caretta spent a great deal of their pelagic lives in floating sargassum beds - thick mats of unanchored seaweed floating in the middle of the ocean. Within these beds, they found ample shelter and food. In the absence of sargassum beds, turtle young feed in the vicinity of upwelling "fronts"