Phytoplankton and water quality parameters in the Patos Lagoon estuary and adjacent marine coast

Study Extent

Phytoplankton and water quality parameters have been continuously sampled since 1993 i.e., the time series comprise over twenty years of environmental and biological data.

Sampling

The following physical water parameters are obtained in situ: temperature (mercury thermometer); salinity (optical refractometer or conductivity meter Yellow Spring, mod. 33 SCT); water transparency (Secchi disk). Surface water is sampled with a bucket and stored in the dark in plastic bottles for the analysis of dissolved inorganic nutrients and chlorophyll-a in the laboratory.

Quality Control

Responsible researchers and the classical methods are the same employed since the beginning of the time series. Thus, methodology influence is minimal. Technical assistance for sampling and nutrient analysis changed during the years, and also of phytoplankton counting (six persons), always under supervision of the responsible researchers.

Method steps

1. For phytoplankton counting, surface water samples are stored in amber glass bottles and fixed with lugol´s solution (2%). Plankton is also concentrated by horizontal tows using a 20 μm mesh size plankton net and stored in glass bottles fixed with fomaldehyde (4%) neutralized with hexamethylentetramine.

1. Bacteria
   rank: kingdom
2. Chromista
   rank: kingdom
3. Plantae
   rank: kingdom
4. Protozoa
   rank: kingdom
5. Charophyta
   rank: phylum
6. Chlorophyta
   rank: phylum
7. Ciliophora
   rank: phylum
8. Cryptophyta
   rank: phylum
9. Cyanobacteria
   rank: phylum
10. Euglenozoa
    rank: phylum
11. Myzozoa
    rank: phylum
12. Ochrophyta
    rank: phylum
13. Bacillariophyceae
    rank: class
14. Chlorophyceae
    rank: class
15. Conjugatophyceae
    rank: class
16. Cryptophyceae
    rank: class
17. Cyanophyceae
    rank: class
18. Dictyochophyceae
    rank: class
19. Dinophyceae
    rank: class
20. Euglenoidea
    rank: class
21. Litostomatea
    rank: class
22. Prasinophyceae
    rank: class
23. Pyramimonadophyceae
    rank: class
24. Raphidophyceae
    rank: class
25. Trebouxiophyceae
    rank: class
26. Ulvophyceae
    rank: class
27. Aulacoseirales
    rank: order
28. Bacillariales
    rank: order
29. Chaetocerotanae incertae sedis
    rank: order
30. Chattonellales
    rank: order
31. Chroococcales
    rank: order
32. Conjugatophyceae
    rank: order
33. Coscinodiscales
    rank: order
34. Cyclotrichiida
    rank: order
35. Cymatosirales
    rank: order
36. Dictyochales
    rank: order
37. Dinophysiales
    rank: order
38. Eutreptiida
    rank: order
39. Fragilariales
    rank: order
40. Gonyaulacales
    rank: order
41. Gymnodiniales
    rank: order
42. Halosphaerales
    rank: order
43. Hemiaulales
    rank: order
44. Leptocylindrales
    rank: order
45. Lithodesmiales
    rank: order
46. Melosirales
    rank: order
47. Naviculales
    rank: order
48. Noctilucales
    rank: order
49. Nostocales
    rank: order
50. Oscillatoriales
    rank: order
51. Paraliales
    rank: order
52. Peridiniales
    rank: order
53. Prorocentrales
    rank: order
54. Rhizosoleniales
    rank: order
55. Surirellales
    rank: order
56. Synechococcales
    rank: order
57. Thalassionematales
    rank: order
58. Thalassiosirales
    rank: order
59. Triceratiales
    rank: order
60. Ulotrichales
    rank: order
61. Aphanizomenonaceae
    rank: family
62. Aphanothecaceae
    rank: family
63. Aulacoseiraceae
    rank: family
64. Bacillariaceae
    rank: family
65. Ceratiaceae
    rank: family
66. Chaetocerotaceae
    rank: family
67. Coscinodiscaceae
    rank: family
68. Cymatosiraceae
    rank: family
69. Dictyochaceae
    rank: family
70. Dinophysiaceae
    rank: family
71. Diploneidaceae
    rank: family
72. Entomoneidaceae
    rank: family
73. Eutreptiaceae
    rank: family
74. Fragilariaceae
    rank: family
75. Gloeotilaceae
    rank: family
76. Gonyaulacaceae
    rank: family
77. Gymnodiniaceae
    rank: family
78. Hemiaulaceae
    rank: family
79. Leptocylindraceae
    rank: family
80. Leptolyngbyaceae
    rank: family
81. Lithodesmiaceae
    rank: family
82. Melosiraceae
    rank: family
83. Merismopediaceae
    rank: family
84. Mesodiniidae
    rank: family
85. Microcystaceae
    rank: family
86. Naviculaceae
    rank: family
87. Noctilucaceae
    rank: family
88. Nostocaceae
    rank: family
89. Paraliaceae
    rank: family
90. Peridiniaceae
    rank: family
91. Pleurosigmataceae
    rank: family
92. Polykrikaceae
    rank: family
93. Prorocentraceae
    rank: family
94. Protoperidiniaceae
    rank: family
95. Pseudanabaenaceae
    rank: family
96. Pterospermataceae
    rank: family
97. Rhizosoleniaceae
    rank: family
98. Skeletonemaceae
    rank: family
99. Stephanopyxidaceae
    rank: family
100. Surirellaceae
     rank: family
101. Thalassionemataceae
     rank: family
102. Thalassiosiraceae
     rank: family
103. Triceratiaceae
     rank: family
104. Akashiwo
     rank: genus
105. Alexandrium
     rank: genus
106. Amphidinium
     rank: genus
107. Aphanocapsa
     rank: genus
108. Asterionellopsis
     rank: genus
109. Aulacoseira
     rank: genus
110. Bacillaria
     rank: genus
111. Bacteriastrum
     rank: genus
112. Binuclearia
     rank: genus
113. Campylosira
     rank: genus
114. Cerataulina
     rank: genus
115. Ceratoneis
     rank: genus
116. Chaetoceros
     rank: genus
117. Coscinodiscus
     rank: genus
118. Dactyliosolen
     rank: genus
119. Detonula
     rank: genus
120. Dictyocha
     rank: genus
121. Dinophysis
     rank: genus
122. Diploneis
     rank: genus
123. Ditylum
     rank: genus
124. Entomoneis
     rank: genus
125. Guinardia
     rank: genus
126. Gyrodinium
     rank: genus
127. Gyrosigma
     rank: genus
128. Hemiaulus
     rank: genus
129. Leptocylindrus
     rank: genus
130. Leptolyngbya
     rank: genus
131. Lithodesmium
     rank: genus
132. Melosira
     rank: genus
133. Mesodinium
     rank: genus
134. Meuniera
     rank: genus
135. Microcystis
     rank: genus
136. Neocalyptrella
     rank: genus
137. Nitzschia
     rank: genus
138. Noctiluca
     rank: genus
139. Odontella
     rank: genus
140. Paralia
     rank: genus
141. Peridinium
     rank: genus
142. Planktolyngbya
     rank: genus
143. Pleurosigma
     rank: genus
144. Polykrikos
     rank: genus
145. Proboscia
     rank: genus
146. Prorocentrum
     rank: genus
147. Protoperidinium
     rank: genus
148. Pseudo-nitzschia
     rank: genus
149. Pseudosolenia
     rank: genus
150. Pterosperma
     rank: genus
151. Raphidiopsis
     rank: genus
152. Rhizosolenia
     rank: genus
153. Scrippsiella
     rank: genus
154. Skeletonema
     rank: genus
155. Stephanopyxis
     rank: genus
156. Surirella
     rank: genus
157. Synedra
     rank: genus
158. Thalassionema
     rank: genus
159. Thalassiosira
     rank: genus
160. Torodinium
     rank: genus
161. Trieres
     rank: genus
162. Tripos
     rank: genus
163. Chaetoceros (Hyalochaeta)
     rank: subgenus
164. Chaetoceros (Phaoceros)
     rank: subgenus
165. Akashiwo sanguinea
     rank: species
166. Alexandrium fraterculus
     rank: species
167. Asterionellopsis guyunusae
     rank: species
168. Aulacoseira granulata
     rank: species
169. Bacillaria paxillifera
     rank: species
170. Binuclearia lauterbornii
     rank: species
171. Campylosira cymbelliformis
     rank: species
172. Cerataulina bicornis
     rank: species
173. Ceratoneis closterium
     rank: species
174. Chaetoceros subtilis
     rank: species
175. Coscinodiscus wailesii
     rank: species
176. Dactyliosolen fragilissimus
     rank: species
177. Detonula pumila
     rank: species
178. Dictyocha fibula
     rank: species
179. Dinophysis acuminata
     rank: species
180. Dinophysis caudata
     rank: species
181. Ditylum brightwellii
     rank: species
182. Guinardia delicatula
     rank: species
183. Guinardia flaccida
     rank: species
184. Gyrodinium fusus
     rank: species
185. Leptocylindrus danicus
     rank: species
186. Leptocylindrus minimus
     rank: species
187. Melosira moniliformis
     rank: species
188. Meuniera membranacea
     rank: species
189. Neocalyptrella robusta
     rank: species
190. Noctiluca scintillans
     rank: species
191. Paralia sulcata
     rank: species
192. Peridinium quinquecorne
     rank: species
193. Polykrikos schwartzii
     rank: species
194. Prorocentrum compressum
     rank: species
195. Prorocentrum cordatum
     rank: species
196. Prorocentrum micans
     rank: species
197. Prorocentrum scutellum
     rank: species
198. Pseudosolenia calcar-avis
     rank: species
199. Rhizosolenia setigera
     rank: species
200. Scrippsiella trochoidea
     rank: species
201. Skeletonema costatum
     rank: species
202. Skeletonema tropicum
     rank: species
203. Stephanopyxis turris
     rank: species
204. Thalassionema nitzschioides
     rank: species
205. Trieres chinensis
     rank: species
206. Trieres mobiliensis
     rank: species
207. Tripos furca
     rank: species
208. Tripos muelleri
     rank: species

The Patos Lagoon at the southern Brazilian coastal plain (Rio Grande do Sul state) is the largest (10,360 km2) choked lagoon in the world stretching in a NE SW direction from the city of Porto Alegre (30°30’ S) to Rio Grande (32°12’ S). In the southern estuarine region, approximately 10 % of total area, a single and narrow inlet connects this lagoon to the Atlantic Ocean. The major tributary rivers at the northern and central areas of Patos Lagoon, and the São Gonçalo Channel at the southern area, are significant freshwater sources from an extensive drainage basin. The hydrodynamics of the Patos Lagoon estuary is strongly controlled by the discharge of tributary rivers and the action of predominant meteorological factors like winds, rainfall and evaporation.