Traditionally, marine researchers collect data in their own field of expertise, often with a confined temporal and spatial range. These data are then normally used in a rather limited context. The Marine Biodiversity and Ecosystem Functioning Network of Excellence (MarBEF) implemented besides 17 other research projects the MANUELA project. MANUELA – Meiobenthic and Nematode biodiversity: Unravelling Ecological and Latitudinal Aspects – aimed to integrate the scattered information on the dynamics and the functional role of meiofauna into one single database so that joint analyses could be performed. 
Creating the MANUELA database
During 15 months (from December 2005 to February 2007) the data for the MANUELA project was collected. Twelve European institutes delivered 83 datasets containing data on the spatial distribution of meiofauna. Although the data covered a very wide geographical range – from the Arctic to the Antarctic – the focus was on European marine and estuarine habitats.
Upon arrival each dataset was archived and described in detail at the data centre of the Flanders Marine Institute (VLIZ). Describing these datasets in a standardised way made it possible to create a searchable metadata inventory. This metadata - data about the data- helps scientists to discover desired data and also enables them to share their data with other scientists. Archiving the datasets prevents them from being lost by ensuring the long-term integrity of the data. All child datasets can be found here
Before these datasets could be integrated to create the MANUELA database, they had to be standardised. This meant verifying whether the same taxonomy, geographical names, abiotic variables and the same methodology was used. To verify that all datasets used the same taxonomy, species lists were matched against the European Register for Marine Species (ERMS). 
The MANUELA database
The MANUELA database contains data, collected between 1966 and 2006, from 1283 sampling sites from all over the world, although most samples were collected at The North-East Atlantic region, the North Sea and the Mediterranean. A total of 5638 samples, collected at these sites were included in the database and represent 139.426 distribution records. The depth of the sites varied from -0,8 m (samples above the low water mark) to 8380 m. The database contains a total of 1864 unique taxon names, ranging from phylum to subspecies level. As the database mainly focussed on nematodes and copepods, these were most strongly represented with respectively 954 and 269 unique species names. Of the 954 nematode species 333 were newly introduced into ERMS. Furthermore, the MANUELA database also contains biometric information (length, width and biomass) and abiotic parameters (grain size, nutrients, temperature,...) 
The MANUELA project gave scientist the opportunity to perform large-scale analyses of the nematode and copepod communities on an European and even larger scale. Six mayor topics have been addressed:
- large scale patterns in meiobenthic diversity and community composition
- the universal response of meiobenthos to disturbance,
- patterns in marine nematode morphometry,
- patterns in deep-sea nematode communities,
- prediction of nematode biodiversity by using artificial neural networks
- large scale patterns in harpacticoid copepod community composition and diversity.
The first phase of the project lead to the following publications:
- Schratzberger, M.; Lampadariou, N.; Somerfield, P.J.; Vandepitte, L.; Vanden Berghe, E. (2009). The impact of seabed disturbance on nematode communities: linking field and laboratory observations. Mar. Biol.: 1-16
- Vandepitte, L.; Vanaverbeke, J.; Vanhoorne, B.; Hernandez, F.; Bezerra, T.N.; Mees, J.; Vanden Berghe, E. (2009). The MANUELA database: an integrated database on meiobenthos from European marine waters. Meiofauna Marina 17: 35-60
Recently a second phase of the project has begone. This involves the continuation of capturing, standardising and integrating datasets. The MANUELA database is undoubtedly the largest integrated database on meiobenthos ever developed. It is hoped that this initiative will attract other scientists and data in the future.
More information can be found on the MANUELA website
The benefits of sharing data among scientists can be increased in several ways, for example by offering co-authorship to data providers when their data are used in publications resulting from an integrated analysis, and by explicitly citing the used datasets.The principles of data sharing and data use can be written down in a data policy document such as the MANUELA declaration of mutual understanding on data sharing. This policy implies that the participating institutes, organisations and/or the collector of the dataset remain owner of their contributed dataset. This document had to be approved by all participants and formed the basis of the trust relationship among scientist and data managers.
It was agreed to transfer the distribution information of meiofaunal taxa from 72 of the 83 datasets to the European node of the Ocean Biogeographic Information System (EurOBIS). This resulted in a contribution of some 100.000 distribution records.