Ecology of harmful algae
Ecology of harmful algae
复制标题
DOI：
10.1007/978-3-540-32210-8
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
E. Granéli;J. T. Turner
中科院分区：
文献类型：
--
作者：
E. Granéli;J. T. Turner
在公海，初级生产几乎完全依靠统称为浮游植物的浮游单细胞或群体微藻的光合作用。底栖藻类只有在极浅的水中才是重要的初级生产者，因为那里有足以进行光合作用的阳光穿透到底部。因此，浮游植物是水生食物链的基础。属于不同分类单位的数十至数百种浮游植物通常在自然群落中共存。浮游植物是微观的，大小从小于1微米到超过100微米不等，世代时间不超过几天。因此，浮游植物种群表现出很大的时间变化，响应于非生物因素，如光，温度，营养物质，和水的运动，和生物因素，如放牧，竞争，寄生，和微生物的攻击。通常情况下，浮游植物的现存量仍然很低，因为这些损失因素通常通过细胞分裂平衡快速的内在生长率。有时，一个或几个物种的增加可以抵消损失，例如某个物种可以控制浮游植物组合，并导致持续数周或更长时间的水华。这种水华是由于有利的浮游植物生长，水文或气象过程增加的物理浓度，以及由于病毒，沉积和放牧等因素造成的损失减少。一些浮游植物大量繁殖会造成不利影响。这些包括氧气消耗，水质美学下降，鱼鳃堵塞或毒性。这种有害藻类（HA）的大量繁殖导致有害藻类大量繁殖（HAB）。在大约5，000种已知的浮游植物中，只有大约300种会形成有害的赤潮生物，以某种方式危害水生生态系统，而且已知其中只有大约80种会产生毒素。一些浮游植物毒素可以在食物链中积累和/或运输到更高的营养级，污染贝类，使其不适合人类食用，或毒害上层消费者，包括鱼类、海鸟、海洋哺乳动物和人类。的经济效应
In the open sea, primary production is almost totally based on photosynthesis by pelagic unicellular or colonial microalgae, collectively known as phytoplankton. Benthic algae are important primary producers only in extremely shallow water where sunlight sufficient for photosynthesis penetrates to the bottom. Thus, phytoplankton are the basis of aquatic food chains. Tens to hundreds of species of phytoplankton belonging to different taxonomic units usually coexist in natural assemblages. Phytoplankton are microscopic, ranging in size from less than 1 µm to more than 100 µm, with generation times of no more than a few days. Thus, phytoplankton populations exhibit large temporal variations in response to abiotic factors such as light, temperature, nutrients, and water movement, and biotic factors such as grazing, competition, parasitism, and microbial attack. Normally, the standing crop of phytoplankton remains low because these loss factors generally balance rapid intrinsic rates of growth through cell division. Occasionally, increases in one or a few species can overcome losses, such that a given species can dominate phytoplankton assemblages and cause blooms lasting for several weeks or more. Such blooms are due to combinations of favorable phytoplankton growth, increased physical concentration by hydrographic or meteorological processes, and reduced losses due to factors such as viruses, sedimentation, and grazing. Some phytoplankton blooms can cause adverse effects. These include oxygen depletion, reduced water quality aesthetics, clogging of fish gills, or toxicity. Blooms of such Harmful Algae (HA) cause Harmful Algal Blooms (HABs). Of the approximately 5,000 known species of phytoplankton, only some 300 species form HABs that are deleterious to aquatic ecosystems in one way or another, and only about 80 of these species are known to be toxin producers. Some phytoplankton toxins can be accumulated and/or transported in food chains to higher trophic levels where they contaminate shellfish, making them unsuitable for human consumption, or poison upper-level consumers, including fish, seabirds, marine mammals, and humans. The economic effects of