Opportunities and challenges of other effective area-based conservation measures (OECMs) for biodiversity conservation

Ability of new protected areas to counteract losses from downgrading, downsizing, and degazettement

Protected area downgrading, downsizing, and degazettement (PADDD) is a common occurrence. Although PADDD is expected to weaken biodiversity protection, PADDD offsets and new unrelated protected areas (PAs) could help restore representation of biodiversity features to the reserve network affected by PADDD. Globally, we analyzed 16 territories with terrestrial PADDD and 4 territories with marine PADDD from 2011 to 2020. Our objective was to evaluate whether PADDD offsets and new PAs could restore the PAs, key biodiversity areas (KBAs), ecoregions, and threatened amphibian, mammal, bird, and reptile species ranges where PADDD had occurred. In our studied territories, offsets of PADDD were rare (enacted in 3 [19%] terrestrial territories and one [25%] marine territory). One territory had PADDD losses that were compensated fully by PADDD offsets in terms of area coverage and ecoregions represented. All other territories failed to achieve compensation goals. In territories affected by PADDD, PADDD offsets and new PAs partially restored area representation (63%) and KBA coverage (57%). However, only 38% of ecoregion representation and 20%, 33%, 31%, and 21% of threatened amphibian, mammal, bird, and reptile representation, respectively, were restored. Overall, we found a large shortfall in PADDD offsets, even when unrelated PAs were included in the calculus. There is an urgent need to expand PADDD offsets and PAs to advance biodiversity conservation and achieve the Global Biodiversity Framework's 30×30 target. Future planning of newly enacted conservation areas needs to prioritize biodiversity conservation and consider the purpose of restoring reserve networks affected by PADDD, rather than solely focusing on areal targets.

A cost-effective approach to identify conservation priority for 30 × 30 biodiversity target on the premise of food security

There is a growing consensus on expanding protected and conserved areas for biodiversity conservation. Nevertheless, it remains uncertain where to expand conserved areas as well as what appropriate management modalities to choose. Moreover, conserved areas expansion should be balanced with crop-related food security challenges. We developed a framework to identify cost-effective areas for expanding protected areas and other effective area-based conservation measures (OECMs), and applied it to China. By combining templates for biodiversity conservation priorities at global scale and the priority conservation areas based on 2413 vertebrates' extinction risk in China, we identified areas with high biodiversity conservation value. We then categorized the priority areas according to human impact, indicating the potential cost of management. As a result of combining the two aspects above, we identified the most cost-effective areas for expanding protected areas and OECMs while excluding both the current and predicted croplands that can be used for food security. The results show that China could expand its protected areas to 22.81 % of the country's land area and establish OECMs in areas accounting for 9.82 % and 17.37 % of the country's land area in a cost-effective approach in two scenarios. In the ambitious scenario, protected and conserved areas would account for a maximum of 40.18 % of terrestrial area, with an average 62.67 % coverage of the 2413 species' suitable habitat. To achieve the goals of protected and conserved areas in Kunming-Montreal Global Biodiversity Framework, countries could apply this framework to identify their protected areas and OECM expansion priorities.

Establishing a protected area network in Xinlong with other effective area-based conservation measures

Protected areas (PAs) are pivotal to biodiversity conservation, yet their efficacy is compromised by insufficient funding and management. So-called other effective area-based conservation measures (OECMs) present a paradigm shift and address PA limitations. Such measures can expand conservation areas, enhance connectivity, and improve the existing system. To assess the conservation status of biodiversity in Tibetan cultural areas in China, we investigated the spatial distribution of wildlife vulnerable to human disturbance (large- and medium-sized mammals and terrestrial birds) in Xinlong, a traditional Tibetan cultural area. In particular, we compared a PA (Xionglongxi Nature Reserve) and OECMs targeting species conservation. We also investigated the relationship of wildlife with human temporal and spatial activities. The OECMs complemented areas not covered by PA, especially in rich understory biodiversity regions. More species in OECMs tolerated human presence than species in the PA. Existing biodiversity reserves failed to cover areas of high conservation value in Tibet and offered limited protection capacity. Expanding PAs and identifying OECMs improved Xinlong's system by covering most biodiversity hotspots. Building on the tradition of wildlife conservation in Tibet, harnessing OECMs may be an effective means of augmenting biodiversity conservation capacity. We recommend further evaluation of OECMs effectiveness and coverage in Tibetan area as a way to enhance the current PA system.

Protecting China's major urban bird diversity hotspots

The Kunming-Montreal Global Biodiversity Framework puts forward a new conservation target to enhance urban biodiversity. Cities have a great potential for sustaining biodiversity and nurturing a healthy relationship between people and our nearest nature. It is especially important in developing countries such as China, which has a rich biodiversity and a rapidly growing urban population. Using citizen science data, we show that 48% of the national bird diversity and 42% of its threatened species have been recorded in the top-20 most avian-diverse cities of China. Urban bird diversity hotspots clustered along the eastern coast, indicating the importance of establishing an inter-city conservation network along the East Asian-Australasian Flyway. This urban conservation network would be a starting point to promote social recognition of biodiversity's relational value in a country with a vast population and an increasingly important role in meeting UN's Sustainable Development Goals.

Progress developing the concept of other effective area-based conservation measures

In 2010, the introduction of other effective area-based conservation measures (OECMs) into international policy caused a paradigm shift in area-based conservation, which included consideration of areas outside formal protected areas and places where biodiversity conservation may not be a management objective for the site. Despite the importance of this shift for global conservation, conservation science and policy have been slow to engage with the concept of OECMs. As the world moves toward protecting 30% of the Earth by 2030, it is imperative to develop evidence-based guidance for how to identify effective conservation measures, especially tools to help evaluate and monitor the biodiversity outcomes associated with potential OECMs. To understand the current progress in developing the concept of OECMs, I evaluated the peer-reviewed literature to consolidate and synthesize current knowledge. I conducted a thematic analysis of papers to identify the types of challenges and opportunities being discussed and lessons from studies evaluating the effectiveness of OECMs. Only 105 studies mentioned OECMs, and those that did rarely move beyond superficial mention of OECMs as part of area-based conservation. Around one-half of studies listed potential risks or benefits of OECMs but none provided evidence these issues have materialized. Twenty-three studies attempted to identify potential OECMs, although specific case studies were rare. The 7 studies that evaluated existing OECMs were highly critical of how they had been implemented to date. Studies that evaluated conservation outcomes were extremely rare, and suggested effectiveness must be judged on a case-by-case basis. The current literature not only leaves many gaps in the science required to operationalize the concept of OECMs, but also often raises additional questions that need to be addressed. If these gaps are not filled by robust science, the promised benefits for biodiversity from OECMs may never be realized.

Beyond protected areas: The importance of mixed-use landscapes for the conservation of Sumatran elephants (Elephas maximus sumatranus)

Elephants were once widely distributed across the Indonesian island of Sumatra but now exist in small, isolated populations. Using the best data available on elephant occurrence, we aimed to (a) predict potential habitat suitability for elephants (Elephas maximus sumatranus) across the island of Sumatra and (b) model landscape connectivity among the extant elephant populations. We used direct sightings and indirect observations of elephant signs, as well as six remotely sensed proxies of surface ruggedness, vegetation productivity and structure, and human land use and disturbance, to model habitat suitability in a Google Earth Engine (GEE) environment. We validated the habitat suitability prediction using 10-fold spatial block cross validation and by calculating the area under the precision-recall curve (AUC-PR), sensitivity, and specificity for each model iteration. We also used a geolocation dataset collected from global positioning system (GPS) collars fitted on elephants as an independent validation dataset. Models showed good predictive performance with a mean AUC-PR of 0.73, sensitivity of 0.76, and specificity of 0.68. Greater than 83% of the independent GPS collar geolocations were located in predicted suitable habitat. We found human modification, surface ruggedness, and normalized difference vegetation index to be the most important variables for predicting suitable elephant habitat. Thirty-two percent, or 135,646 km2, of Sumatra's land area was predicted to be suitable habitat, with 43 patches of suitable habitat located across Sumatra. Areas with high connectivity were concentrated in the Riau and North Sumatra provinces. Though our analysis highlights the need to improve the quality of data collected on Sumatran elephants, more suitable habitat remains on Sumatra than is used by known populations. Targeted habitat conservation, especially of the suitable habitat in and around the Lamno, Balai Raja, Tesso Tenggara, Tesso Utara, Bukit Tigapuluh, Seblat, Padang Sugihan, and Bukit Barisan Selatan ranges, may improve the long-term viability of this critically endangered species.

Progress of Ecological Restoration Research Based on Bibliometric Analysis

With the deterioration of the global/regional ecological environment, ecological restoration plays an important role in sustainable development. However, due to the differences in research methods, objectives, and perspectives, the research results are highly diverse. This makes it necessary to sort the publications related to ecological restoration, clarify the research status, grasp the research hotspots, and predict the future research trends. Here, 23,755 articles from the core database of Web of Science were retrieved, and bibliometric analysis was carried out to understand the global ecological restoration research progress from 1990 to 2022 from a macro perspective, with the aim to determine the future development direction. The results are as follows. (1) From 1990 to 2022, the number of publications in the field of ecological restoration constantly increased, and the fluctuation of the average annual citations increased. The most important articles were published in high-ranking journals. (2) Ecological restoration covers a wide range of research areas, including biodiversity, ecosystem services, climate change, land use, and ecological restoration theories and technologies. The four main hotspots in this field are heavy metal removal, soil microbial biomass carbon and nitrogen concentrations, grassland ecological restoration, and evaluation framework and modeling of ecological restoration's effects. Currently, studies focus on river basin remediation, heavy metal removal, and forest restoration. (3) Future ecological restoration research should strengthen the multi-object aspect and multi-scale ecological restoration research, improve the ecological restoration effect evaluation system, and incorporate social and economic issues. This study identified current research hotspots and predicted potential future research directions, providing a scientific reference for future studies in the field of ecological restoration.

Where ecologically 'tis better to go brown than green: enhanced seagrass macrobenthic biodiversity within the canals of a brownfield coastal marina

At the start of the 21st century, a coastal residential-estate marina was developed on a previously degraded and polluted brownfield island site within Knysna estuarine bay, Garden Route National Park, South Africa, including the creation of 25 ha of new flow-through tidal canals. Canals near the larger entrance to this system now support permanently submerged beds of seagrass, which in turn support abundant macrobenthic invertebrates. In comparison with equivalent seagrass-associated assemblages present in natural channels around the island, those in the artificial marina canals were similarly structured and dominated by the same species, but the marina assemblages were significantly more species-rich (1.4 x on average) and were more abundant. Indeed, this area of marina supports the richest seagrass-associated macrofaunal biodiversity yet recorded from South Africa. The canals created de novo therefore now form a valuable addition to the bay's marine habitat, in marked contrast to the generality that marinas developed on greenfield sites represent a net reduction in intertidal and shallow marine area and associated seagrass-associated benthos. If located and constructed appropriately, brownfield marina development and conservation of coastal marine biodiversity clearly need not be antithetical, and brownfield sites may provide opportunity for the location and management of 'artificial marine micro-reserves' or for the action of 'other effective area-based conservation measures' for soft-sediment faunas.

Beta diversities of grassland birds indicate the importance of pastoralism for nature conservation of the Qinghai–Tibetan plateau

The post-2020 global biodiversity framework calls for a transformative change in food systems. Promoting agricultural multifunctionality is a viable approach to this sustainability transformation. The eastern Qinghai–Tibetan Plateau (QTP) is both one of the world’s largest livestock grazing systems and a hotspot of endemic birds in Asia. In this research, we aim to investigate the impact of livestock grazing on alpine bird assemblages at the local scale (alpha diversity) and their variation across the pastoral landscape (beta diversity). In the study area Nyanpo Yutse, we conducted surveys of 126 bird sample plots during two breeding seasons to acquire bird assemblage data. Meanwhile, we employed unmanned aerial vehicles to measure 2D and 3D habitat features within the 150-m radius. We investigated the key habitat variables driving the spatial distributions of both alpha and beta diversities of birds. Particularly, we partitioned beta diversity into its turnover and nestedness components and tested their patterns across sites of four levels of livestock grazing intensities (LGIs). Our results found no significant correlation between LGIs with species richness of birds, while 2D and 3D habitat complexity and built structure were positively correlated with alpha diversity (p < 0.05). At the landscape scale, pairwise LGI differences had no significant correlation (p > 0.05) with any pairwise beta diversity. The ordination plotting detected distinguished habitat preferences among 12 common birds and eight endemic birds. The multiple-site beta diversity of the 126 plots showed high species turnover (>0.871) where LGI was lower than 1.065 sheep units/ha, indicating the importance of moderate grazing for the conservation of diverse avian assemblages at the landscape scale. Our study demonstrated that extensive pastoralism is important for both maintaining the mosaic landscape and conserving avian biodiversity on the eastern QTP. We unveiled one of the ecological mechanisms through which synergies can be realized to support both agricultural production and biodiversity conservation in the Tibetan grazing system.

Spatiotemporal Variations of Human Pressure on Key Biodiversity Areas in the Qinghai–Tibet Plateau: A Comparative Analysis

A key biodiversity area (KBA) is one of the important emerging area-based conservation measures that is being implemented recently in China; however, the human pressure faced by a KBA is still unclear. This study analyzed the spatiotemporal variation of human pressure on KBAs from 1990 to 2017 and compared it with the human pressure on national natural reserves (NNRs) through a case study of the Qinghai–Tibet Plateau. In addition, changes in the trend of human pressure before and after 2010 were analyzed to examine the influence of conservation policies on human pressure. Results showed that human pressure on KBAs and NNRs gradually increased from 1990 to 2017. Furthermore, the growth rates and mean values of human pressure in KBAs were higher than those in NNRs. After the implementation of conservation policies in 2010, the growth rates of human pressure on both KBAs and NNRs have significantly slowed, and the areas with negative growth in both KBAs and NNRs have gradually expanded. In addition to providing an understanding of the changing spatiotemporal trends of human pressure on KBAs, this study can serve as a reference to formulate policies for the improvement of the effectiveness of conservation.