Twenty astatic ponds near Rome were studied in order to define the relationships between physicochemical variables and macroinvertebrate communities. The main abiotic factor differentiating the ponds was the annual hydrologic cycle. Depth, surface area, and sand percentages in the sediment were higher in permanent ponds, whereas silt+clay content was higher in temporary ones. No difference was recorded in pH, conductivity and oxygen content in the water or organic matter in the sediments between the two pond types. Three main ecological assemblages were distinguished: a) generalist taxa common to both pond types; b) taxa associated with and adapted to temporary ponds; and c) taxa which seemed to prefer permanent ponds. Overall, there was no relationship between number of taxa and surface area, except for Odonata and aquatic macrophytes. A positive correlation was observed between number of macrophyte species and macroinvertebrate taxa richness, and particularly of odonates and chironomids, suggesting that an increase in aquatic vegetation species leads to an increase in microhabitats and suitable food, substrate, andor refuge from predators. Odonata seemed also to prefer more stable and sunny ponds. DICOTYLEDONES Um belliferae Callitrichaceae Apium inundatum (L.) Reichenb. Fil CaNitriche obfusangula Le Gall Oenanfhe sp. Callifriche stagnalis Scop. Ceratophylhceae MONOCOTYLEDONES Ceratophyllum submersum L. Alismataceae Elatinncepe Alisma lanceolafum With. Elatine alsinastrum L. Damasonium alisma Miller Haloragaeepe Juncaceae Myriophyllum alternijlorum DC. Juncus efisus L. Labiatae Lemnaceae Mentha pulegium L. Lemna minor L. Lentibnlariaceae Poaceae Ufricularia vulgaris L. Agrostis sp. Polygonaceae Gliceria notafa Chevall. Polygonum sp. Phragmifes australis Cavill Ranunculaceae Potamogetonaceae Ranunculus aquatilis L. Pofamogefon natans L. Ranunculus ophioglossifolius Vill. Potamoge ton polygonifolius Poumt Ranunculus peltatus Schrank Potamogeton trichoides Cham. and Schlecht

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Characterizing and monitoring changes in biogenic 3‐dimensional (3D) structures at multiple scales over time is challenging within the practical constraints of conventional ecological tools. Therefore, we developed a structure‐from‐motion (SfM)‐based photogrammetry method, coupled with inspection and mesh processing software, to estimate important ecological parameters of underwater worm colonies (hummocks) constructed by the sabellariid polychaete Sabellaria alveolata, using non‐destructive, 3D modeling and mesh analysis. High resolution digital images of bioconstructions (hummocks) were taken in situ under natural conditions to generate digital 3D models over different sampling periods to analyse the morphological evolution of four targeted hummocks. 3D models were analysed in GOM Inspect software, a powerful and freely available mesh processing software to follow growth as well as morphology changes over time of each hummock. Linear regressions showed 3D models only slightly overestimated the real dimensions of the reference objects with an average error < 5% between measured and model‐estimated dimensions for both length and volume. Manual inspection of models and semi‐automated surface‐to‐surface comparison allowed the computation of important metrics linked to the ecology of temperate reefs such as volume, surface area, surface complexity/rugosity, number and size of holes and creeks and the mean density of living worms per colony. Moreover we demonstrated the reliability of 3D surface complexity estimates against two linear rugosity measures: a traditional and a virtual variant of the ‘chain‐and‐tape’ method. Finally, besides 3D models deviation analysis via surface comparison, a Bayesian latent variable model approach was adopted to highlight the significative effects of sea state conditions on S. alveolata hummocks metrics. We demonstrated without damaging the benthic organisms that SfM approach allow continuous study of temperate bioconstruction leading to a fine description of short‐term structural modification mediated by hydrodynamics, making this technique accessible and repeatable to many other areas of ecological research.