Ada Hayden Lake Essay

Nitrogen and phosphorus are the major limiting nutrient elements in a variety of aquatic ecosystems and are altered by anthropogenic activities; such as row crops, feed lots, and humans (Elser et al. 2007). Larger inputs of nitrogen cause an abundance of phytoplankton and macrophyte production (Ferree and Shannon 2001).The purpose of this study was to examine nitrogen and phosphorus levels at Ada Hayden Lake in the comparative context of their effect on phytoplankton abundance as well as toxicity. Based on previous labs, we have found Ada Hayden Lake to be mesotrophic-eutrophic; this supported our prediction. According to Table 2 in the appendices, the amount of D.O. decreased resulting in a lot of change. Our chlorophyll a content was 18.26 ug/L (table 1 in the appendices). Furthermore, the abundance of phytoplankton sampled from Ada Hayden supports our prediction (Table 3 and Figure 3, in appendices). We found more cyanobacteria and green algae which are more commonly found in mesotrophic lakes (Claustre 1994). The results of our …show more content…
My partner and I hypothesized that Ada Hayden’s nitrogen and phosphorus levels would be moderate because based on previous labs, we discovered Ada Hayden to be mesotrophic. Therefore, with very little nitrogen and phosphorus the lake would be oligotrophic and higher concentrations of nitrogen and phosphorus would make the lake eutrophic; we believe it’s in between. Since our mean chlorophyll a levels from a previous lab at Ada Hayden were 18.26 ug/L (Table 1 in the appendices), we think that there will be a moderate level of phosphorus. According to Guildford and Hecky (2000), chlorophyll a concentrations increase with an increase in total phosphorus. Likewise, phosphorus increases phytoplankton abundance, especially cyanobacteria (Xu et al.