Ecosystem Restoration in Protected Areas: Progress and Strategies

CHENG Chaonan,LI Feng,YANG Rui,LÜ Jing

Ecosystem restoration,considered a critical component of environmental conservation activities worldwide,is essential for sustainable development.Currently,18% of China's land area is covered by protected areas (PAs),ahead of the Aichi Target of the UN Convention on Biological Diversity (CBD).Nevertheless,the ecosystems in PAs in China are still under significant degradation pressure,and about 10% are in a highly vulnerable state.

Therefore,the article first described the importance,objectives and principles,restoration process and technical methods of ecosystem restoration in PAs.Secondly,it identified the principal types of ecosystems in PAs in China,including forest,grassland and wetland ecosystems,and analyzed the distribution and causes of ecosystem degradation.Then we summarized the current problems and concerns and proposed six restoration strategies.Finally,this paper provided suggestions for the ecosystem restoration activities of PAs in China,ranging from policy formulation and management mechanisms to financing channels.

1 Method

Through literature review,case compilation and expert screening,we selected 24 typical cases of ecosystem restoration in PAs around the world,including 12 domestic and 12 international cases.These cases involved various aspects of planning,financing and implementation of ecosystem restoration,covering a wide range of ecosystem types such as forests and woodlands;grasslands,shrubs and alpine grasslands;and wetlands (rivers,streams and lakes,coastal wetlands).Furthermore,the study took five national parks,namely Qianjiang-source National Park,Giant Panda National Park,National Park of Hainan Tropical Rainforest,Shandong Yellow River Delta Nature Reserve and Three-River-Source National Park,as typical cases for field research and semi-structured interviews.

2 Ecosystem Restoration Progress in PAs in the World

Ecosystem degradation is a widespread and critical problem,with 2 billion hm2of land already degraded in the world,losing 50% of forests,50% of coral reefs and 70% of wetlands,and approximately 12 million hm2of land showing degradation each year.Unsustainable land use and overexploitation of natural resources are reducing carbon stocks,the supply of ecosystem services and the ability to support biodiversity.Creating and expanding the extent and size of PAs is one of the key measures to reverse and stop ecosystem degradation.

2.1 Significance

International institutions focus on protecting ecosystem integrity,assessing ecosystem services and net gain,protecting biodiversity and invasive species prevention and control,addressing climate change and marine ecosystem restoration,wilderness protection and rewilding,and adaptive management.Based on the "social-economic-natural" complex ecosystem theory,most research on ecosystem conservation and restoration in PAs in China is related to humancentered social and economic systems and natural and ecological systems.In the context of China's ecological civilization construction and ecological protection and restoration of territory space,it is significant to carry out ecosystem restoration in PAs in the following three aspects.

2.1.1 Protecting and restoring ecosystem integrity

Restoration in and around PAs is a vital priority of the International Union for Conservation of Nature (IUCN) and CBD Conservation Reserve Work Program,which encourages countries to develop and implement measures related to restoring and rebuilding ecosystem integrity.

2.1.2 Promoting optimization of net gain

The net gain is the measurable composite result of ecological conservation restoration activities of ecosystem integrity,biodiversity and human wellbeing.Restoration activities in PAs can,on the one hand,improve the understanding of Nature-based Solutions (NbS) and,on the other hand,inspire people to take broader action in their daily lives to enhance the resilience of ecosystems to climate change.

2.1.3 Coordinating ecological conservation and community development

A healthy and resilient protected area can create more opportunities for regional development.By creating a platform for awareness,education and research,we can transform the perceptions and productive lifestyles of the community,thereby effectively collaborating with conservation and community development.

2.2 Objectives and principles

Ecosystem restoration has been short of detailed objectives similar to ecosystem conservation.This study consolidated and summarized the principles,goals,targets and indicators for ecosystem restoration in PAs to support the implementation and evaluation of ecosystem restoration activities.

2.3 Restoration processes

Ecosystem degradation is defined as the deviation of an ecosystem as a result of natural or humaninduced disturbances.Ecosystem restoration is described as the process of stopping and reversing ecosystem degradation.It usually involves removing and controlling interferential factors,diagnosing the degradation problem,identifying reference ecosystems and baselines,and selecting negative or positive technical approaches according to succession.

2.4 Technical approach

The technical approach to ecosystem restoration consists of four main models: natural regeneration,assisted regeneration,ecological reconstruction and conservation.The perspective of respecting nature,responding to nature,protecting nature and the harmonious co-existence of human and nature,the selection of ecosystem restoration techniques for PAs in China should adhere to the principles of natural regeneration as the mainstay and combine natural regeneration and artificial restoration.We should restore degraded,damaged and destroyed ecosystems,connect ecological corridors and reconstruction of biological habitats,and implement abandoned land management,to enhance the originality and integrity of the ecosystems of PAs.

2.4.1 Natural regeneration

Natural regeneration methods are applied to lightly degraded areas.Based on the elimination of stressors,the natural succession of ecosystems in an orderly direction relies on their capacity for selfregulation.Three-River-Source National Park is a typical model for restoring grassland ecosystems using natural regeneration methods.Yellowstone National Park in the USA carries out wetland ecosystem restoration by maintaining a substantial research and monitoring capacity.

2.4.2 Assisted regeneration

Assisted regeneration can be used in moderately or more degraded areas,where further active interventions are used to trigger natural ecosystem recovery by eliminating degradation stressors.Qianjiangyuan National Park restored barren hills through assisted regeneration.The formation of artificial wetlands through ecological recharge in India's Keoladeo National Park is a typical model of the assisted regeneration approach to restoring wetland ecosystems.

2.4.3 Ecological reconstruction

Severely degraded areas require the elimination or reversal of degradation threat factors and the reintroduction of all or most of their desirable biotopes,where possible,to correct all biotic and abiotic damage and thus restore the area to the state of the native reference ecosystem.Nepal's community-based forest landscape restoration program is a typical model for ecological reconstruction.Shandong Yellow River Delta Nature Reserve form a positive cycle of the "river-land-beach-sea" ecosystem through ecological reconstruction.

2.4.4 Conservation

Conservation is the preservation of biological species,the habitats with different biomes depend,and the culture and traditions of the indigenous inhabitants,to maintain the perpetual existence and sustainable use of natural resources,of which wilderness protection and rewilding are typical models.Yosemite National Park balanced wilderness protection with visitor experience in the USA.Pleistocene Park restored grassland ecosystems through rewilding in Russia.

3 Status of Degradation and Problems of the Ecosystem in PAs in China

3.1 Degradation distribution

In recent decades,China has suffered relatively severe ecosystem degradation,mainly covering forest,grassland and wetland ecosystems.The overall degradation situation is as follows: 1) the Qinghai-Tibet Plateau and the Qaidam Basin mainly show degradation of grassland ecosystems;2) the western Greater Khingan mountains,the North China Plain,the Hengduan Mountains,the South of the Five Ridges,the Daba Mountains and the Sichuan Basin are mainly characterized by degraded forest ecosystems;3) there is relatively severe soil erosion in the Loess Plateau region;4) the middle and lower reaches of the Yangtze and Yellow rivers,as well as estuaries and coastal zones,are mainly dominated by degraded wetland ecosystems,covering river wetlands,lake wetlands and coastal wetlands.

3.2 Causes

Changing natural and socio-economic conditions accelerate biodiversity loss and ecosystem degradation in PAs.On a regional scale,natural factors are one of the primary causes of ecosystem degradation.While on a local and small scale,inappropriate human activities are also one of the principal causes of ecosystem degradation in many global nature reserves.

3.3 Issues and challenges

China has proposed policy support and technical guidance on ecosystem restoration at the national level,and national parks have carried out practices related to ecosystem restoration.We found some problems with ecosystem restoration activities in PAs in China.1) It is still lacking ecological background surveys and assessments.2) The ecological monitoring system needs to be improved,and the data-sharing mechanism is missing.3) It is a failure to advocate natural recovery solutions and restoration projects within small-scale and single elements.4) The sustainability of financial investment in ecosystem restoration activities is limited,and the participation of multiple actors and the market system is poor.5) The enthusiasm for community participation has not been fully exploited.6) Insufficient consideration has been given to the effective participation of all stakeholders in ecosystem restoration activities.

3.4 Focus

Specifically,ecosystem restoration activities in PAs should focus on the following eight aspects: 1) Protecting and restoring climate-sensitive ecosystems;2) Strengthening the restoration of ecological processes;3) Optimizing the contribution of natural capital and ecosystem services in reserves;4) Strengthening biodiversity conservation;5) Controlling invasive species;6) Implementing wilderness protection and rewilding;7) Actively responding to natural disasters caused by climate change;8) Emphasizing cultural and traditional knowledge restoration.

4 Strategies for Ecosystem Restoration in PAs in China

4.1 Strategy 1: Selecting a reasonable reference ecosystem

Based on comprehensive background survey data,it is reasonable to define the objectives of ecosystem restoration and select a suitable reference ecosystem to support the development of an ecosystem restoration plan.Meanwhile,extensive historical and monitoring data and the continuous benchmarking of reference ecosystems in the restoration process can support the maintenance and management of ecosystem restoration projects after implementation.

4.2 Strategy 2: Ensuring long-term financial support for monitoring and maintenance activities

Building a long-term effective monitoring and database platform can help managers and stakeholders to identify potential risks and provide the necessary information to support the development of techniques and methods for ecosystem restoration,feedback mechanisms for adaptive management and the construction of scientific research and cooperation platforms.

4.3 Strategy 3: Moving from site-scale to regionalscale system restoration

We should achieve a systematic shift in ecosystem restoration from the site scale to the regional scale in pursuit of regional development to enhance ecosystem quality.Ecological protection and restoration of national space emphasize a systematic,integrated and regionwide perspective to protect,restore and manage ecosystems,in order to improve the stability and security of regional ecosystems as a whole.

4.4 Strategy 4: Realizing multiple financing and costbenefit assessment

In addition to government funds for ecosystem restoration activities in PAs,we should advocate diversified financing approaches to reduce financial pressure on central and local governments,and ensure the sustainability of restoration activities.Moreover,the application of a cost-benefit evaluation index system to assess the effectiveness of the implementation of ecosystem restoration projects in PAs will help to engage social capital in the construction of PAs in an effective way.

4.5 Strategy 5: Strengthening community cooperation and education

Ecosystem restoration activities can promote community education,and well-designed ecosystem restoration projects also can serve as tourist attractions within PAs to promote ecosystem restoration concepts and ideas.

4.6 Strategy 6: Promoting multi-stakeholder participation

It is the basis point awareness and understanding of ecosystem restoration in PAs by all stakeholders for effective implementation of related restoration activities.Ecosystem restoration activities are a shared responsibility of the public and private sectors and stakeholders at local,regional,national and global levels.We should always promote inclusiveness and shared participation in governance,social justice and equity throughout the restoration process.

5 Conclusion

This study systematically reviewed the literature and typical cases of ecosystem restoration in PAs at home and abroad.We also described the significance,objectives and principles,restoration processes and technical methods of ecosystem restoration in PAs.In the context of the global propagation of NbS and the intensified ecological protection and restoration of territorial space in China,we proposed specific restoration strategies for the challenges and critical points of ecosystem restoration in PAs in China.Meanwhile,this paper provided the following three suggestions for the successful implementation of ecosystem restoration: 1) to promote the development of policies,2) to improve the management mechanism,and 3) to enhance the funding sustainability for ecosystem restoration in PAs.