鹭鸟对茶园的生态影响

The Ecological impact of egrets on tea plantations

目前国内对鹭鸟(夜鹭Nycticoraxnyticorax、白鹭Egrettagarzetta、苍鹭Ardeacinerea、池鹭Ardeolebacchus)的迁徙、觅食习性和繁殖规律的已有详细的研究报道,但鹭鸟自身活动对栖息地的生态影响尚未见报道。作者对鹭鸟对茶园土壤和茶树的影响进行了研究,结果表明,大量鹭鸟活动所产生的鸟粪对栖息地的茶树土壤中各种养分的质量分数产生了重大影响:有机质提高了28.03%～62.25%,土壤速效磷增加了1.7～4.2倍,土壤水溶性盐提高了6～21倍之多,并发生了严重盐化;pH表土升高0.43,下层降低了1.11。对茶树的重大影响表现为:叶绿素a、叶绿素b以及总的质量分数,分别减少25.72%、36.97%、29.54%;叶子正面皮孔也被堵塞,生长发育受阻,叶子边缘、叶尖等处发生焦枯;影响轻的茶芽中茶多酚的质量分数下降了3.7%,水浸出物的质量分数略高1%,氨基酸的质量分数提高7.4%;影响严重的茶树的生物产量降低达76%以上,局部经济产量为零,甚至茶树濒临枯死。

There are many researches on rules of migration, foraging habits and breeding of egrets （Nycticorax nyticorax, Egretta garzetta, Ardea cinerea and Ardeole bacchus）, however, there seems to be no report on ecological impact of its activity on the habitat. In the present paper, the ecological impact of egrets on the soil and trees of tea plantations was studied for the first time. The results indicate that droppings produced by frequent activity of egrets make a great effect on soil nutrient of the tea tree＇s habitat. The organic compound increased by 28.03% - 62.25%, the rapidly available phosphorus of soil increased by 1.7-4.2 times, water soluble salt content of soil increased by 6 - 21 times, and serious salinization has happened. The pH of top soil raises 0.43, and the lower layer has been reduced by 1.11. The great impacts on the tea tree are shown as follows： Chlorophyll a, chlorophyll b, and their total content, are reduced by 25.72%, 36 97%, and 29.54% separately. The pores of the obverse side of the leaves are blocked, tree growth is obstructed, and the leaf margin and leaf apex shrivel. The polyphenol content of tea bud has dropped by 3.7% in the slight influenced areas. The content of water oozes is slightly more than 1%, and the amino acid content increases by 7.4%. But in the serious influenced areas, the biological output is reduced by more than 76%, even the economic yield is zero in some of them, and the serious cases are on the verge of withering.