Browsing by Author "Green, Andy J."

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    Biological invasion modifies the co-occurrence patterns of insects along a stress gradient
    (2017) Carbonell, José Antonio; Velasco, Josefa; Millán, Andrés; Green, Andy J.; Coccia, Cristina; Guareschi, Simone; Gutiérrez‐Cánovas, Cayetano
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    Modelling Water Depth, Turbidity and Chlorophyll Using Airborne Hyperspectral Remote Sensing in a Restored Pond Complex of Doñana National Park (Spain)
    (2024) Coccia, Cristina; Pintado, Eva; Paredes, alvaro L.; Aragones, David; O'Ryan, Daniela C.; Green, Andy J.; Bustamante, Javier; Diaz-Delgado, Ricardo
    Restored wetlands should be closely monitored to fully evaluate the effectiveness of restoration efforts. However, regular post-restoration monitoring can be time-consuming and expensive, and is often absent or inadequate. Satellite and airborne remote sensing systems have proven to be cost-effective tools in many fields, but they have not been widely used to monitor ecological restoration. This study assessed the potential of airborne hyperspectral remote sensing to monitor water mass characteristics of experimental temporary ponds in the Mediterranean region. These ponds were created during marsh restoration in Do & ntilde;ana National Park (south-west Spain). We used hyperspectral images acquired by the CASI-1500 hyperspectral airborne sensor to estimate and map water depth, turbidity and chlorophyll a in a subset of the 96 new ponds. The high spatial and spectral resolution of the CASI sensor allowed us to detect differences between ponds in water depth, turbidity and chlorophyll a, providing accurate mapping of these three variables, and a useful method to assess restoration success. High levels of spatial variation were recorded between different ponds, which likely generates high diversity in the animal and plant species that they contain. These results highlight the great potential of hyperspectral sensors for the long-term monitoring of wetland complexes in the Mediterranean region and elsewhere.
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    The life cycle of the alien boatman Trichocorixa verticalis (Hemiptera, Corixidae) in saline and hypersaline wetlands of south-west Spain
    (2019) Cespedes, Vanessa; Coccia, Cristina; Antonio Carbonell, Jose; Sanchez, Marta I.; Green, Andy J.
    Trichocorixa verticalis (Corixidae) is native to North America but is well established as an alien in the Western Mediterranean region, where it is invasive in permanent coastal wetlands with high salinities. We investigated the annual cycle and generation time of T. verticalis in the introduced range in south-west Spain, through a combination of field surveys and laboratory experiments. Field surveys were conducted on a monthly basis over 1year in three saline fish ponds in Donana and four hypersaline salt ponds in the Odiel marshes. Adults were present all year round, whereas nymphs were only absent in August, when temperatures and salinities were high. Adult sex ratios were idiosyncratic and often male or female biased for a given location and month. Adults were smaller during summer months. Laboratory experiments revealed an oviposition rate of 11.5eggsper day and a generation time of about 54days from egg to adult, suggesting T. verticalis may complete around six generations per year in permanent wetlands. A combination of a high oviposition rate and continuous reproduction throughout the year gives T. verticalis an advantage over native corixid competitors (Sigara spp), and appears to explain the success of this alien aquatic insect.