Conservatoire et Jardin botaniques de la Ville de Genève
Système d'Information du Patrimoine Vert
Highly threatened by human pressure, the diversity of Geneva's flora and vegetation must be protected. The Conservatoire et Jardin botaniques de la Ville de Genève (CJB) has acquired a vast knowledge of, and extensive data on, the flora and the vegetation. This information must be completed, updated, and made available to the persons who activities are linked with the conservation of biological diversity in Geneva. The current problems identified are:
- Dispersion of data within the various Government departments and amongst the different collaborators;
- A disparity of data, both thematically and geographically;
- A variety of media, often obsolete;
- Gaps, both geographic and temporal;
- A lack of homogeneity in the structure of the knowledge;
- A lack of tools for updating, broadcasting and interactive consultation for policy makers, particularly for the results of the work and studies mandated;
- A lack of effective tools for treatment and analysis.
Therefore, the CJB initiated the project SIPV to address these major gaps.
Geographically, this project extends to the limits of the Geneva basin. Initially, our efforts have been concentrated on the territory of the Canton of Geneva.
This projet is part of the Système d'Information de la Ville de Genève (SITV), a partner of the Système d'Information du Territoire à Genève (SITG). It bears the label Agenda 21 of the City of Geneva.
Thematically, the target of our project is the integration of knowledge and monitoring of the evolution of biodiversity in the region. Our first efforts, based on the speciality of the Institution, have been consecrated to plant diversity. Therefore, four main modules have been developed:
- Isolated trees: survey all the individual trees (excluding forestry). This represents about 300,000 individuals for the entire Canton of Geneva;
- Green spaces: record all the parks maintained by the City of Geneva in the municipality;
- Wild flora: synthesize all the data on the Geneva flora (currently over 120,000 observations). These data come mainly from the Centre du Réseau Suisse de Floristique (CRSF), based in Geneva (CJB);
- Natural habitats: achieve an updated map of the natural habitats present in the Canton of Geneva for the purpose of, amongst others, better management.
This programme is led by a Steering Committee consisting of the managers of the municipal services concerned (CJB, DSIC, SEVE). Annually, this committee sets the years goals and validates the balance sheets.
Within the context of the Aalborg Project the bryophytes in the territory of the City of Geneva will be inventoried. This projet is complementary to the Red List of Geneva Bryophytes project and the data that it generates on the city bryophytes will be contributed to the Atlas of Geneva. The principal habitats concerned are the walls, trees, green spaces and the vascular plant delimited prioritaty sites. An Action Plan for Grimmia crinita will be written in 2013. This species is considered to be threatened within Switzerland and is found on walls within the City of Geneva. The main objectives are to inventory the bryophytes in various sites within the City of Geneva, to highlight interesting sites by function of their species richness and the presence of threatened species, and to establish Action Plan's for the protection of such species and sites.
We contribute to the knowledge base for the module Isolated Trees at these two levels:
a) species: nomenclature, ecology;
b) individuals: integration of all existing cantonal and communal inventories. This represents fifteen themes (Plane trees, remarkable trees, fruit trees, ...), or geographical inventories, totalling more than 255,000 observations.
All surveys made at the scale of the canton are centralized in the Information System. This will ultimately represent about 300,000 individuals, with multiple observations made over time.
All information relating to the flora is centralized in the Centre du Réseau Suisse de Floristique (CRSF) based at the CJB. The CRSF is the National center for observations on the flora in Switzerland. Extraction of the data on Geneva is done periodically to serve the data within this perimeter. This module has facilitated the creation of unique data stream for the various stakeholders (mandatees, mandating bodies, institutions, ...).
This flow accelerates the circulation of information within the canton of Geneva and reduces the time between the acquisition in the field and the dissemination of data on the flora.
In addition, the project SIPV-FS participated in entering the attributary data on species that are specifically from Geneva (Red List GE, GE legislation, ...).< br />I In a second phase, we optimized the recording of data via the creation of field tools. This further shortens the time between the collection and dissemination of data through web services which is useful to policymakers and to the public. These sites will be complementary to that of the CRSF ( www.crsf.ch a>).
We currently have a mapped record of natural habitats in the Canton of Geneva, which dates from the 1990s. This knowledge has been updated from time to time, resulting in heterogeneity, both temporally and spatially, in the knowledge of the distribution of these habitats.
Initially this project aims to synthesize and harmonize the existing data sets on the natural habitats. These include updating the legend using a common reference, taken from Delarze & Gonseth (2008). Secondly, it aims to achieve a complete and homogeneous mapping of these entities. We will rely on the existing maps of land use (SEMO). We will use remote sensing techniques including the orthophotos (2009), and the technique of dynamic segmentation. The objects are labelled thematically in sixty classes based on their spectral, morphological, textural and contextual characteristics. The study area for the development of the method was the watershed of Versoix. At first, we extrapolated the method to encompass the canton and then to the entire Geneva Basin area. A version with a coarser resolution (10 m) may subsequently be offered across the city.
Thanks to the techniques developed, data updating can be done much more frequently and at lower cost. The periodicity corresponds to the acquisition of orthophotos, which is currently one flight every four years.
This mapping of natural habitats is an essential tool for environmental management, both in the Canton of Geneva as well as for its surroundings. This information is essential for the interpretation of the ecological value of the landscape and of its potential to serve as a corridor, particularly for wildlife.