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波罗的海的富营养化可能已潜在地增加了蓝藻细菌藻华发生的频率和规模。富营养化导致有机沉积物的增加,底层缺氧状况的加剧以及随后的系统内磷负荷的加重。此外,低氧水体积呈现与无机氮库负相关的关系,提示随低氧程度的增加,总氮的消除也会增加。系统内磷负荷加重和溶解的无机氮消除的增加将导致较低的氮磷比,而低的氮磷比是促进固氮蓝藻细菌藻华发生的主要原因之一。因为波罗的海开阔水域的蓝藻细菌藻华似乎被其内部作用所强有力地调控,因此,外部营养物质消减的影响与尺度相关。在较长的时间尺度上,外部磷负荷的减少可能会降低蓝藻细菌藻华的发生;然而,在较短时间尺度上,内部磷负荷可能会抵消外部磷负荷的降低。这些可诱导内部负荷(增加)、氮清除以及固氮蓝藻细菌占优势的耦合的过程,可被定性地描述为一种具有潜在自驱式的“恶性循环”。为了有效抑制蓝藻细菌藻华以及所有的富营养化征象,削减氮和磷外部负荷似乎是至关重要的。
The eutrophication of the Baltic Sea may have potentially increased the frequency and scale of cyanobacterial bacterial algal blooms. Eutrophication led to an increase in organic deposits, an increase in hypoxic conditions at the bottom, and a subsequent increase in phosphorus loading within the system. In addition, the volume of hypoxic water showed a negative correlation with the inorganic nitrogen pool, suggesting that with the increase of the degree of hypoxia, the total nitrogen elimination would also increase. The increase of phosphorus loading and dissolution of inorganic nitrogen in the system will lead to a lower N / P ratio, while the low N / P ratio is one of the main reasons for promoting the production of nitrogen-fixing cyanobacteria algal blooms. Because the cyanobacterial algal blooms in the open waters of the Baltic Sea seem to be strongly regulated by their internal actions, the effects of external nutrient depletion are related to the scale. On longer time scales, a reduction in external phosphorus load may reduce cyanobacterial bacterial algal bloom; however, on a short time scale, the internal phosphorus load may offset the decrease in external phosphorus load. These processes, which can induce internal loading (uptake), nitrogen scavenging, and predominant coupling of nitrogen-fixing cyanobacteria, can be characterized qualitatively as a “self-propelled” vicious circle. " In order to effectively inhibit the cyanobacterial algal blooms and all the signs of eutrophication, it seems crucial to reduce the external loads of nitrogen and phosphorus.