las comunidades de peces del río guadiamar y el accidente minero ...

More documents

Recommendations

Info

Análisis del proceso de recolonización del tramo afectado del Guadiamar PERMANOVA revealed no significant differences between years in E1 (F (1,8) = 1.187; p = 0.345). However, these differences were significant for E2 (F (1,8) = 4.4854; p = 0.008), E4 (F (1,8) = 3.2358; p = 0.015) and marginally significant (p < 0.1) for E3 (F (1,8) =2.0664; p = 0.091) and E5 (F (1,8) = 3.2667; p = 0.056). In the PERMANOVA with site, sample and site-year interaction, site accounted for 31% (p = 0.001) of the variance explained by the model; year accounted for 10% (p = 0.001); and site-year interaction accounted for 10% (p = 0.032). Thus, the model explained 52 % of the variance. The four species with highest weight in the assemblage dynamics deserve special attention. L. sclateri maintained a high abundance in all sites since 2001, resulting slightly higher in E5 at the end of the study period (Fig. 8a). P. willkommii was mainly restricted to the upstream non-affected reach of the Guadiamar River, even though it was common for some individuals to reach the adjacent affected E2. Since 2005, seven years after the spill, P. willkommii abundance has increased in the reference site (E1), but decreased in the affected reach (Fig. 8b). Among the exotic species within the affected sites, L. gibbosus greatly increased in 2000, but abundance decreased from the following year, and values were stable hereinafter (Fig. 8c). A. alburnus was absent until the last sampling year. However, in that year this species was the second most abundant in the affected reach. This last abrupt expansion of a particular species confirms a deep change in fish assemblage structure. (a) (b) (c) Figure 8. Abundance dynamics for three species in sampling sites (E1-E5) along the Guadiamar River following the April 1998 spill th: (a) L. sclateri, (b) P. willkommii and (c) L. gibbosus. X- axis represents time and y-axis abundance values. 93
Las comunidades de peces del río Guadiamar y el accidente minero de Aznalcóllar Fish recolonization sources Sampling of non-affected tributaries and Doñana marshland area identified fish assemblages that were a likely source of colonizing individuals after the spill removal works (Table 1; Fig. 9). The largest native species assemblage was found in the upstream Guadiamar River main stem (Table 1). This source supplied six native species, L. sclateri, P. willkommii, S. alburnoides, S. pyrenaicus, C. paludica and I. lemmingii, together with two exotics, L. gibbosus and M. salmoides. On the other hand, the largest exotic species assemblage was detected downstream in the Doñana marshland sampling site (Table 1; Fig. 9). Regarding the tributaries, Agrio River and Ardachón stream were potentially the largest lateral contributors, providing native species such as L. sclateri, S. alburnoides and S. pyrenaicus, together with the exotic G. holbrooki and L. gibbosus (Table 1). Downstream, C. paludica was the only species caught in the Alcarayón stream, and Majaberraque stream was the last tributary holding likely colonists, in this case G. holbooki (Fig. 9). 94
Page 1 and 2:
DEPARTAMENTO DE ZOOLOGÍA UNIVERSID
Page 4 and 5:
DEPARTAMENTO DE ZOOLOGÍA UNIVERSID
Page 6 and 7:
TITULO DE LA TESIS: LAS COMUNIDADES
Page 8:
A mi Madre,
Page 11 and 12:
A mis antiguos compañeros del Grup
Page 13 and 14:
Material and Methods 39 Results 45
Page 15 and 16:
ABSTRACT This PhD Thesis analyzes t
Page 17 and 18:
Las comunidades de peces del río G
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
ÁREA DE ESTUDIO Cuenca del río Gu
Page 27 and 28:
Área de estudio Figura 1. Cuenca d
Page 29 and 30:
Área de estudio farallón del Alja
Page 31 and 32:
Área de estudio Principales impact
Page 34:
PARTE I: Ictiofauna de la cuenca de
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 48 and 49:
II.1- Habitat quality affects the c
Page 50 and 51:
Condición somática de L. sclateri
Page 52 and 53:
Condición somática de L. sclateri
Page 54 and 55:
Table 1. Mean habitat variable valu
Page 56 and 57: Condición somática de L. sclateri
Page 66 and 67: II.2- Habitat-fish community relati
Page 68 and 69: Relaciones peces/hábitat en el Gua
Page 76 and 77: Figure 2. Tributary network of the
Page 86: PARTE III: Evolución de la comunid
Page 89 and 90: Las comunidades de peces del río G
Page 99 and 100: Table 1. List of the fish species c
Page 105: Las comunidades de peces del río G
Page 123 and 124: 110
Page 157 and 158:
Page 159 and 160:
146
Page 161 and 162:
Appendix 1. Environmental variables
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198:
Page 199 and 200:
Page 201 and 202:
show all

las comunidades de peces del río guadiamar y el accidente minero ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?