Quels sont les principaux défis et opportunités pour la conservation écologique dans les zones urbaines?

Urban ecosystem services, like air purification and recreation, enhance human health and quality of life but are often degraded by urbanization. Assessing their supply and demand, identifying trade-offs, and integrating them into urban planning is crucial for their protection and enhancement.

Some of the main challenges for urban ecological conservation include fragmentation of natural habitats for urbanization resulting in disrupted wildlife movement and ecosystem, spread of invasive species through transit routes outcompeting native species and the difficulty of engaging public that is often disconnected from nature. However, urban areas also present unique opportunities for conservation, for instance, parks and green belts can serve as refuges for biodiversity, it can serve as a platform for raising public awareness about sustainable urban landscapes and urban ecological conservation and finally an opportunity to integrate nature into urban life providing significant economic and social benefits, enhancing quality of life.

To protect and enhance urban ecosystem services, it is important to assess their supply and demand, identify trade-offs and synergies, and integrate them into urban planning and management.

Main challenges and opportunities for ecological conservation in Urban Areas: 🗝️Pollution Control 🌱Green approach 🪵Deforestation ☁️Climate Change 🌍Biodiversity 🌪️Droughts and heat waves

Environmental contamination: City-based pollution can have direct negative effects on human health and quality of life. Urban expansion: Patterns of city development, like sprawl, may result in environmental harm. Environmental quality: Traffic and congestion in urban areas can lead to poor air conditions. Advantages Urban green areas can offer wildlife habitats and serve as a crucial conservation approach. City planning is essential in guiding sustainable growth. Effective urban design strategies can emphasize ecological concerns, such as: - Maintaining green spaces - Encouraging pedestrian-friendly environments - Incorporating natural elements into urban layouts

Challenges Habitat Loss and Fragmentation: Destruction and isolation of natural habitats. Pollution: Air, water, noise, and light pollution harming ecosystems. Invasive Species: Non-native species disrupting local ecosystems. Limited Green Spaces: Urbanization reducing space for conservation. Human-Wildlife Conflict: Increased interactions causing conflicts. Resource Constraints: Limited budgets, land, and regulations for conservation.

Urban biodiversity is often underestimated, as many species can adapt to urban environments, and some are endemic or rare. To conserve and promote urban biodiversity, it is essential to monitor and inventory its status and trends, protect and restore habitats and corridor

In order to preserve biodiversity in urban areas, it is necessary to protect urban habitats and establish connections between them so that species can move safely between different habitat areas within the city. For example, if several natural, semi-natural green patches, or urban parks are considered habitats with the highest biodiversity, these valuable patches should be protected, and urban expansion toward them should be prevented. Physical connections between these patches should be established. For instance, green corridors or eco-bridges can be used to create links and continuity between these patches.

To enhance green infrastructure, the first step is to identify the landscape structure. After mapping the landscape elements, including green patches, corridors, nodes, networks, and matrices, disturbed areas and those with gaps, disconnections, and lack of continuity should be identified. Appropriate strategies should then be proposed to create connectivity in these regions. A continuous network of green spaces is sustainable, can host and support rich biodiversity, and provides numerous ecosystem services for the city.

Cultural norms are currently the biggest challenge to good green infrastructure. Humans have known how to put green space into urban areas for millenia - this isn't a technical problem. The challenge Australian cities have now is cultural, and changing mindsets about green infrastructure being 'a bonus', a 'nice to have', an 'optional extra' or something that is going to cost more and take more maintenance than just concreting over whatever available space there is - or developing it for private profit. This is going to take systems thinking because the benefits of installing green infrastructure instead of more hardstand spaces is almost priceless - and even in fiscal terms, we certainly can't afford the alternatives.

aneighborhoods to cities and regions. To optimize urban green infrastructure, it is crucial to adopt a holistic and participatory approach, consider multiple objectives and criteria, and coordinate across sectors and disciplines.

The easy answer is to develop urban forests, ecological corridors, water bodies and generous parks & open spaces. But easier said than done; in the highly competitive land market in urban areas and skyrocketing land costs, it doesn’t seem feasible. However the possibilities are there specially if these initiatives are undertaken in suburbs or further away from suburbs, which will help to attract biodiversity and have pleasant effect on environment. This could be better option for society rather than leaving land at mercy of real estate developers who are good in developing urban ghettos.

After mapping the landscape structure, you can identify disturbed and degraded areas on the map. By using historical maps or aerial photos from previous times, you can observe the original land uses in the area. This gives you the opportunity to find ways to restore these degraded areas to their original state.For example, if there is a degraded river, you can work to revitalize the river and restore it to its original state.

Ecological restoration actually requires a high degree of technical knowledge gained by experimental trials and an iterative approach. You need to go way beyond clear goals, diverse stakeholders and adapting to change. City of Melbourne have some great examples of restoration of exotic lawns to urban meadows - they started with exotic flowers and are now trialling local native wildflowers and grassy species. The other challenge is that ecological restoration is extremely expensive, regardless of whether it is urban or rural, and it's far better to avoid land clearing in key biodiversity hotspots to begin with!

O principal desafio da conservação urbana é sensibilizar gestores e tomadores de decisão sobre os benefícios da criação de áreas protegidas, considerando aspectos como a melhoria da qualidade de vida, o aumento da resiliência urbana frente às mudanças climáticas e a promoção de serviços ecossistêmicos. Existe também a necessidade de capacitação e engajamento de servidores municipais em temas referentes à legislação ambiental (Sistema Nacional de Unidades de Conservação, no caso do Brasil) e investimentos no planejamento e implementação.

If you're reading this as a practitioner in this space, the best thing you can do is look around at local governments that are leading in this space. I'm aware that City of Melbourne in Australia has been leading innovative practice and on-ground trials on this topic for several years, and they have an urban ecology strategy that underpins it. More broadly our city used to pride itself of the Green Wedges Strategy that dictated urban land use decisions through the late decades of the 20th C. I'd welcome other people reading this with expertise from other cities/countries to highlight resources and case studies they think would be helpful.