Biodiversity of microcrustaceans in iberian wetlands, with a focus on non-native species, ostracoda and rice fields

• Autores: Maria Bisquert Ribes
• Directores de la Tesis: J Francesc Mezquita Juanes (dir. tes.), Xavier Armengol Díaz (codir. tes.)
• Lectura: En la Universitat de València ( España ) en 2025
• Idioma: español
• Número de páginas: 400
• Tribunal Calificador de la Tesis: Julio M. Rodríguez Lázaro (presid.), María Teresa Antón Pardo (secret.), Sanda Iepure (voc.)
• Programa de doctorado: Programa de Doctorado en Biodiversidad y Biología Evolutiva por la Universitat de València (Estudi General)
• Menciones:
  • Internacional
• Calificación: Sobresaliente Cum Laude
• Materias:
  • Ciencias de la vida
    • Biología animal (zoología)
      • Ecología animal
  • Ciencias de la tierra y del espacio
    • Hidrología
      • Limnología
• Enlaces
  • Tesis en acceso abierto en: TESEO
• Resumen

  • Mediterranean wetlands, though limited in area, support diverse ecosystems but face pressures from agricultural conversion and invasive species. This thesis investigates microcrustacean biodiversity, focusing on the Albufera de València and Marjal de Pego-Oliva natural parks, with an emphasis on ostracods and invasive species. The study identified 115 species of cladocerans, copepods, and ostracods, with ostracods being predominant. Rice fields, despite their artificial nature, exhibited higher species richness compared to the other habitats studied (marshes, limnocrenes, and the lake). Species composition varied across habitats, strongly influenced by seasonality, which shaped community structures. Temperature and oxygen levels were key factors, particularly in rice fields and marshes. Cooler conditions favoured certain species in winter and warmer climates benefited others in summer. Seasonality was less relevant in limnocrenes, where habitat characteristics had a stronger influence in microcrustacean communities. The ostracod metacommunity from rice fields of the Iberian Peninsula was especially influenced by historical and spatial factors rather than local environmental conditions. Despite the annual ploughing, current communities showed a notably continuity with those of the past. Nonetheless, more sensitive species may have colonised rice fields during flooding, facilitated by irrigation canals, agricultural machinery, or waterbirds. However, dispersal was somewhat limited, as indicated by the presence of distinct species in different regions and higher homogeneity within each of them. Waterbirds were found to aid dispersal, with hatching patterns of resting forms from bird faeces influenced by temperature. At a low temperature, typical of winter, some species appeared, while at a higher temperature characteristic of summer, some species typical of this season hatched. The potential impacts of global change on temperature regimes might alter the hatching patterns of propagules affecting microcrustacean dynamics. This thesis highlights the role of invasive microcrustacean species on biodiversity and community dynamics, particularly in environments like rice fields. Twenty invasive microcrustacean species, mostly ostracods, were detected, with rice fields acting as entry points to other habitats. Many invasive species were detected in summer, but some were also found in winter. This work describes a new invasive ostracod species, Vizcainocypria viator, through morphological and genetic analysis, while discussing its possible origins and emphasizing the importance of taxonomic studies. By examining biodiversity dynamics in artificial and natural wetlands, the thesis demonstrates how rice fields can serve as refuges for microcrustacean biodiversity, including invasive species, in the face of the increasing scarcity of natural wetlands.