User:CarolinaStudent/Nature-based solutions

Practical implementation
NBS are determined by site-specific natural and cultural contexts that include local and scientific knowledge. Geographic information systems (GIS) can be used as an analysis tool to determine sites that may succeed as NBS (Mubeen et al., 2021). GIS can function in such a way that site conditions including slope gradients, water bodies, land use and soils are taken into account in analyzing for suitability (Mubeen et al., 2021). The resulting maps are often used in conjunction with historic flood maps to determine the potential of floodwater storage capacity on specific sites using 3D modelling tools (Mubeen et al., 2021). Comparison of suitability maps to digital imagery from Google Earth is also often practiced as a way of ensuring that suitability maps are representative of actual conditions. F NBS can be implemented alone or in an integrated manner along with other solutions to societal challenges (e.g. technological and engineering solutions) and are applied at the landscape scale.

Implementing NBS is often dependent on political, economic, and scientific challenges. Private sector investment is needed to supplement traditional sources of capital such as public funding or philanthropy. The challenge is to provide a robust evidence base for the contribution of nature to economic growth and jobs, and to demonstrate the economic viability of these solutions – compared to technological ones – on a timescale compatible with that of global change. Already, multiple case studies have demonstrated that NBS are more economically viable than traditional technological infrastructures (Costa et al., 2021; Hankin et al., 2021). Furthermore, it requires measures like adaptation of economic subsidy schemes, and the creation of opportunities for conservation finance, to name a few. Indeed, such measures will be needed to scale up NBS interventions and strengthen their impact in mitigating the world's most pressing challenges.

Projects supported by the European Union[edit]
Since 2016, the EU has supported a multi-stakeholder dialogue platform (ThinkNature) to promote the co-design, testing, and deployment of improved and innovative NBS in an integrated way. The creation of such science-policy-business-society interfaces could promote market uptake of NBS. The project is part of the EU’s Horizon 2020 Research and Innovation program, and will run for 3 years. There are a total of 17 international partners involved, including the Technical University of Crete (Project Leader), the University of Helsinki and BiodivERsA.

In 2017, as part of the Presidency of the Estonian Republic of the Council of the European Union, a conference called “Nature-based Solutions: From Innovation to Common-use” was organized by the Ministry of the Environment of Estonia and the University of Tallinn. This conference aimed to strengthen synergies among various recent initiatives and programs related to NBS launched by the European Commission and by the EU Member States, focusing on policy and governance of NBS, research, and innovation.

Nature-based Solutions in the Paris Agreement[edit]
The Paris Agreement calls on all Parties to recognize the role of natural ecosystems in providing services such as that of carbon sinks. Several articles including 5.2 and 7.1 include references to Nature Based Solutions, although not by name. Article 5.2 encourages Parties to adopt conservation and management as a tool for increasing carbon stocks and and Article 7.1  encourages Parties to build the resilience of socioeconomic and ecological systems through economic diversification and sustainable management of natural resources. The Agreement refers to Nature (ecosystems, natural resources, forests) in 13 distinct places. An in-depth analysis  of all Nationally Determined Contributions submitted to UNFCCC, revealed that around 130 NDCs or 65% of signatories commit to nature-based solutions in their climate pledges, suggesting broad consensus for the role of Nature in helping to meet climate change goals. However, high-level commitments rarely translate into robust, measurable actions on-the-ground.

Nature-based solutions at the UN climate action summit in September 2019[edit]
In the 2019 UN Climate Action Summit, nature-based solutions were one of the main topics covered, and were discussed as an effective method to combat climate change. A "Nature-Based Solution Coalition" was created, including dozens of countries, led by China and New Zealand.

Efficacy of NBS
A global systemic map of evidence was produced to determine and  illustrate the effectiveness of NBS (Chausson). After sorting through 386 case studies with computer programs, the study found that NBS were just as if not more effective than traditional or alternative flood management strategies(Chausson). 66% of cases evaluated reported positive ecological outcomes, 24% did not identify a change in ecological conditions and less than 1% reported negative impacts. Furthermore, NBS always had better social and climate change mitigation impacts(Chausson).

Evidence gathered from other case studies supports these claims in that NBS are effective at achieving their desired goals, however one caveat that appears is that green infrastructure, common in NBS practices, must be used in conjunction with traditional grey infrastructure (Chen et al., 2021). Using green infrastructure alone or grey infrastructure alone are less effective than when the two are used together (Chen et al., 2021).

Caveat of Efficacy
While NBS are successful in flood management, a majority of case studies and examples of NBS are from the Global North, resulting in a lack of data for many medium- and low-income nations (Chausson et al., 2020). Consequently, many ecosystems and climates are excluded from existing studies as well as cost analyses in these locations. Further research needs to be conducted in the Global South to determine the efficacy of NBS on climate, social and ecological standards.

Additionally, it is crucial that grey infrastructures continue to be used with green infrastructures (Chen et al., 2021). Multiple studies recognize that while NBS is very effective and improves flood resilience when simulated, it is unable to act alone and must be in coordination with grey infrastructure (Chen et al., 2021, Kourtis et al., 2021). When NBS is used alongside grey infrastructure the benefits transcend flood management and improve social conditions, increase carbon sequestration and prepare cities for planning for resilience (Hankin et al., 2021).

NBS Classes
NBS is a broad group of strategies to use ecosystems as an aid in managing environmental challenges and has a variety of classes that have come before it. In the 1970s a popular approach in the U.S. was that of Best Management Practices (BMP) for using nature as a model for infrastructure and development while the UK had a model for flood management called “Sustainable Drainage Systems” (Qi et al., 2020). Another framework called “Water Sensitive Urban Design” (WSUD) came out of Australia in the 1990s while Low Impact Development (LID) came out of the U.S. (Qi et al., 2020). Eventually New Zealand reframed LID to create “Low Impact Urban Design and Development” (LIUDD) with a focus on using diverse stakeholders as a foundation. Then in the 2000s the western hemisphere largely adopted “Green Infrastructure” for stormwater management as well as enhancing social, economic and environmental conditions for sustainability (Qi et al., 2020).

Definitions
Other European groups see NBS as a restoration and infrastructure based approach to providing social, economic and political benefits (Qi et al., 2020). Another perspective of NBS is that of solutions that use ecological and environmental services to address contemporary environmental, social and economic challenges (Hankin et al., 2021).

Examples
The following table shows examples from around the world: