Evidence of short-term burial response by benthic macrofauna associated with the Mediterranean seagrass Cymodocea nodosa

Abstract

ABSTRACT. Sedimentation and burial affect a variety of habitats worldwide, especially within coastal marine systems. In the Mediterranean, seagrasses like Cymodocea nodosa are commonly subjected to sedimentation and, although the response of C. nodosa has been documented, few studies have included macrofaunal responses. We used a manipulative field experiment to examine the effects of a single small-scale, pulse burial event on benthic invertebrate macrofauna. Burial did not affect the total abundance, richness, or diversity of higher taxa nor the live abundance or diversity after 5 days. However, live higher taxa richness decreased by day 3. After 5 days, such decrease reversed and partial recovery seemed to occur. Almost 2 months later, three of the buried plots remained with some additional sedimentation, but the other three had lost their sediment. We compared faunal metrics of buried plots between days 5 and 54 and found greater diversity on day 54, providing evidence that macrofaunal recovery apparent 5 days after burial seemed to persist. Although we likely underestimated the effects and can only be conservative with our conclusions, taken together our results suggest small-scale, pulse burial events can have some negative effects on the C. nodosa-associated benthic macrofaunal community, but the community can recover within a few weeks.Key words: benthic macrofauna, Cymodocea nodosa, Mediterranean Sea, recovery, sediment. RESUMEN.La sedimentación y el enterramiento afectan a una gran variedad de hábitats en todo el mundo, especialmente en los sistemas costeros marinos. En el Mediterráneo, las fanerógamas marinas como Cymodocea nodosa suelen estar expuestas a la sedimentación y, a pesar de que la respuesta de C. nodosa ha sido documentada previamente, muy pocos estudios hacen referencia a cómo responde la macrofauna. Se ha usado un experimento manipulativo en el campo para examinar los efectos de un enterramiento súbito y puntual a pequeña escala sobre la fauna de invertebrados macrobentónicos. El enterramiento no afectó a la abundancia total, riqueza o diversidad de especies, ni tampoco a la abundancia o diversidad de individuos vivos 5 días después del enterramiento. Sin embargo, la riqueza de taxones vivos disminuyó a partir del día 3. Pasados 5 días, esa disminución revirtió y parece tener lugar una recuperación parcial. Casi 2 meses después, tres de las parcelas enterradas todavía presentaron algún tipo de sedimentación adicional, pero las otras tres habían perdido el sedimento. Se compararon las métricas de la fauna encontrada en los días 5 y 54 en las parcelas enterradas, y se encontró una alta diversidad para el día 54, evidenciando que la aparente recuperación que tuvo lugar 5 días después del enterramiento parece persistir. A pesar de que probablemente hemos subestimado los efectos y debemos ser conservadores con nuestras conclusiones, al examinar los resultados conjuntamente, sugieren que estos eventos repentinos y puntuales de enterramiento a pequeña escala pueden tener efectos negativos sobre...

Spatiotemporal Dynamics of Mediterranean Shallow Coastal Fish Communities along a Gradient of Marine Protection

“…Given emergent effects of biological invasions and climate-driven changes to Mediterranean ecosystems, ongoing efforts that include spatial protections are urgently needed to preserve the integrity of their habitats, marine populations, and coastal communities. As recently documented, it is likely that in the time since our study, many factors have continued to affect both unprotected and protected regions of the western Mediterranean [62][63][64][65]80,85,[87][88][89][90][91][92][93]103,105,[108][109][110][113][114][115]. While our study was initiated ten years prior to its publication, the information contained in this work provides valuable baselines for which to compare ongoing monitoring of shallow fish communities and their habitats within and surrounding the reserve.…”

“…As climatic and anthropogenic pressures continue to affect Mediterranean coastal habitats [62,65,[86][87][88][89][90][91][92][93]108,109], ongoing multiyear monitoring of reserve effectiveness, habitat quality, and biological stability remains necessary. Recurring examination of marine reserves among their encompassed habitats has demonstrated the importance of spatial management protections toward maintaining and enhancing biological communities [54,57,66,70,78,79].…”

“…Our study highlights the ecological consequences of continued exploitation and human activity throughout southeastern Spanish coastal regions. Low fish densities and high patchiness of habitats continue to be observed in unprotected areas as a result of continued fishing pressure, destructive practices, nutrient loading, and desalination [85,[87][88][89][90][91][92]104,105,[108][109][110]. While 22 reserve networks occur in portions of the Spanish Mediterranean, they only make up~8% of the exclusive economic zone [111,112].…”

“…Although management actions are working to address some stressors, their effectiveness has been limited to specific locations [85,[87][88][89][90][91][92]104,105,[108][109][110]. In addition, as other ocean uses and the human population continue to increase throughout the Mediterranean, their effects are likely to intensify within shallow coastal habitats, reinforcing the importance of ongoing protections and broader management approaches [62][63][64][65]85,[87][88][89][90][91][92]104,105,[108][109][110]. Given emergent effects of biological invasions and climate-driven changes to Mediterranean ecosystems, ongoing efforts that include spatial protections are urgently needed to preserve the integrity of their habitats, marine populations, and coastal communities.…”

“…Outside of the Tabarca reserve, the study area, extending from the northern limits of Cabo de las Huertas (CH) to the southern point of Santa Pola (SP) just offshore the Centro de Investigación Marina de Santa Pola (CIMAR), is open to fishing and has been historically overexploited [41][42][43][44][80][81][82][83][84][85][86]. Additional anthropogenic pressures, including the effects of land reclamation, eutrophication, desalination, tourism, and marine litter, have been documented in this region [85,[87][88][89][90][91][92].…”