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Although 23% of Thailand's land is in protected areas, these are vulnerable to climate change. We used spatial distribution modelling for 866 vertebrate and 591 plant species to understand potential climate change impacts on species in protected areas. Most mammals, birds, and plants were projected to decline by 2070, but most amphibians and reptiles were projected to increase. By 2070 under RCP8.5, 54% of modeled species will be threatened and 11 nationally extinct. However, SDMs are sensitive to truncation of the climate space currently occupied by habitat loss and hunting, and apparent truncation by data limitations. In Thailand, lowland forest clearance has biased records for forest-dependent species to cooler uplands (> 250 m a.s.l.) and hunting has confined larger vertebrates to well-protected areas. In contrast, available data is biased towards lowland non-forest taxa for amphibians and reptiles. Niche truncation may therefore have resulted in overestimation of vulnerability for some mammal and plant species, while data limitations have likely led to underestimation of the threat to forest-dependent amphibians and reptiles. In view of the certainty of climate change but the many uncertainties regarding biological responses, we recommend regular, long-term monitoring of species and communities to detect early signals of climate change impacts., (© 2022. The Author(s).)

Summary: Deserts represent key carbon reservoirs, yet as these systems are threatened this has implications for biodiversity and climate change. This review focuses on how these changes affect desert ecosystems, particularly plant root systems and their impact on carbon and mineral nutrient stocks. Desert plants have diverse root architectures shaped by water acquisition strategies, affecting plant biomass and overall carbon and nutrient stocks. Climate change can disrupt desert plant communities, with droughts impacting both shallow and deep‐rooted plants as groundwater levels fluctuate. Vegetation management practices, like grazing, significantly influence plant communities, soil composition, root microorganisms, biomass, and nutrient stocks. Shallow‐rooted plants are particularly susceptible to climate change and human interference. To safeguard desert ecosystems, understanding root architecture and deep soil layers is crucial. Implementing strategic management practices such as reducing grazing pressure, maintaining moderate harvesting levels, and adopting moderate fertilization can help preserve plant–soil systems. Employing socio‐ecological approaches for community restoration enhances carbon and nutrient retention, limits desert expansion, and reduces CO2 emissions. This review underscores the importance of investigating belowground plant processes and their role in shaping desert landscapes, emphasizing the urgent need for a comprehensive understanding of desert ecosystems. [ABSTRACT FROM AUTHOR]

Drylands, comprising semi‐arid, arid, and hyperarid regions, cover approximately 41% of the Earth's land surface and have expanded considerably in recent decades. Even under more optimistic scenarios, such as limiting global temperature rise to 1.5°C by 2100, semi‐arid lands may increase by up to 38%. This study provides an overview of the state‐of‐the‐art regarding changing aridity in arid regions, with a specific focus on its effects on the accumulation and availability of carbon (C), nitrogen (N), and phosphorus (P) in plant–soil systems. Additionally, we summarized the impacts of rising aridity on biodiversity, service provisioning, and feedback effects on climate change across scales. The expansion of arid ecosystems is linked to a decline in C and nutrient stocks, plant community biomass and diversity, thereby diminishing the capacity for recovery and maintaining adequate water‐use efficiency by plants and microbes. Prolonged drought led to a −3.3% reduction in soil organic carbon (SOC) content (based on 148 drought‐manipulation studies), a −8.7% decrease in plant litter input, a −13.0% decline in absolute litter decomposition, and a −5.7% decrease in litter decomposition rate. Moreover, a substantial positive feedback loop with global warming exists, primarily due to increased albedo. The loss of critical ecosystem services, including food production capacity and water resources, poses a severe challenge to the inhabitants of these regions. Increased aridity reduces SOC, nutrient, and water content. Aridity expansion and intensification exacerbate socio‐economic disparities between economically rich and least developed countries, with significant opportunities for improvement through substantial investments in infrastructure and technology. By 2100, half the world's landmass may become dryland, characterized by severe conditions marked by limited C, N, and P resources, water scarcity, and substantial loss of native species biodiversity. These conditions pose formidable challenges for maintaining essential services, impacting human well‐being and raising complex global and regional socio‐political challenges. [ABSTRACT FROM AUTHOR]

The draft post-2020 Global Biodiversity Framework asks CBD parties to conserve at least 30% of the planet by 2030 'through a well-connected and effective system of protected areas ... with the focus on areas particularly important for biodiversity'. We use Thailand as a case study for the ability of a densely populated, hyper diverse, tropical, middle-income country to meet this target at a national level. Existing protected areas (PAs) total 24.3% of Thailand's land area. Adding forest on government land adjacent to existing PAs, plus unprotected areas of Ramsar sites, raises this to 29.5%. To assess the importance for biodiversity, we used modeled distributions of birds and mammals plus, as proxies for other biodiversity components, elevation, bioclimate, forest type, and WWF ecoregion. All modeled species occur in the current PA system but <30% meet representation targets. Expansion of the system increases the proportion of mammals and birds adequately protected and increases the protection for underrepresented bioclimatic zones and forest types. The expanded system remains fragmented and underrepresents key habitats, but opportunities for increasing protection of these are limited. It is also still vulnerable to climate change, although projected impacts are reduced. Additional protection is needed for wetland and coastal habitats, and limestone karsts. [ABSTRACT FROM AUTHOR]

With changing climates globally, we see changes in not just average conditions, but also in extreme events, and such events require special attention due to their unpredictable yet significant impact on native biotas. One such event is the formation of a landscape scar at Zonag Lake caused by a climate change‐induced outburst flooding event that occurred on 15 September 2011. During the winter, the scar region became a new birthplace for sandstorms, and since the flooding, remote sensing monitoring shows that between 2011 and 2020, there were 285 sandstorm days (between November and March), relative to none prior. The outburst flooding event and consequential sandstorms threaten the key lambing area of the Tibetan antelope (Chiru), affect the water balance of the Zonag Lake and downstream lakes, and may even impact on the flow in the Yangtze River. Active human intervention may be needed to repair this new desert spit and reverse the slew of consequences which may otherwise lead to significant population declines in one of the major Chiru breeding grounds due to the progressive loss of vegetation productivity across their main breeding area. [ABSTRACT FROM AUTHOR]

We examined both historical (1960s) and recent (2017) specimens of an insectivorous bat species (Hipposideros armiger) and a phytophagous bat (Rousettus leschenaultii) from the same latitudinal range to explore phenotypic responses to environmental change in China over the past 65 years. Hipposideros armiger exhibited significant increases in forearm length and three diet-related cranial traits, as well as carbon and nitrogen stable isotope composition, suggesting that modern H. armige r must travel farther for food and may now use different food resources. In contrast, R. leschenaultii showed no change in forearm length but displayed significant increases in diet-related cranial traits. This study provides evidence for differential responses to recent environmental changes in bat species with different diets. The changes in diet-related traits of the two species and the forearm length change on the insectivorous bats suggest that recent phenotypic changes may be adaptions to land-use changes rather than to climate change. [ABSTRACT FROM AUTHOR]

Climate change is likely to alterwildfire regimes, but the significance of climate-driven factors in regional fire regimes over extended temporal scales is poorly understood. Comparison of the reconstructed fire dynamics from charcoals in sediments with modern active fires may provide clues about the drivers of wildfire activities, and help us validate models of fire activity for both the past and the future. Microscopic charcoals fromMiocene sediments in Wenshan Basin (Yunnan, southwestern China), were used to reconstruct fire dynamics in deep time. Palaeoclimatic data were obtained from the previous quantitative reconstruction using pollen samples from a sedimentary sequence. The relationship between palaeoclimatic parameters and the ratio of charcoals during the Miocene was explored, and compared with maximumentropy (Maxent) model results throughout different time periods. Our results indicate that the temperature in the dry season was the main factor controlling the frequency of fire in Wenshan during theMiocene. Maxent modeling results based on the modern active fire dataset of Yunnan Province from NASA Earth observations are consistent with the results from fossil sediment analysis, that dry season temperature is the main driver of fire activity. Our findings suggest a significant fire-temperature relationship under the monsoonal climate since the Neogene. Furthermore, models suggest that the last-glacial maximum (LGM) had lower levels of fire activity than present, which increased during the Holocene prior to reaching present levels. Models also predict increases in fire activity across most of Yunnan in the future. [ABSTRACT FROM AUTHOR]

Southeast Asia (SE Asia) is a known global hotspot of biodiversity and endemism, yet the region is also one of the most biotically threatened. Ecosystems across the region are threatened by an array of drivers, each of which increases the probability of extinction of species in a variety of ecosystems. These issues are symptomatic of the issues that face the global tropics; however, with around 4 billion people in the wider region and the associated pressures on biodiversity, this region may be under some of the greatest levels of biotic threat. Deforestation rates in SE Asia are some of the highest globally, additionally it has the highest rate of mining in the tropics, around the greatest number of hydropower dams under construction, and a consumption of species for traditional medicines which is a threat to biodiversity globally. In this review, the greatest threats to regional biodiversity in the SE Asian region are discussed. Tree-plantations and deforestation represent one of the most imminent threats, and some countries have already lost over half their original forest cover (i.e., the Philippines, parts of Indonesia), with projections of as much as 98% loss for some regions in the coming decade. Hunting and trade represent a significant threat as demand stems not only for food, but also for medicine, for ornamentation, and as a status symbol. Mining represents a frequently overlooked threat, as the Asian region is one of the greatest exporters of limestone and various minerals globally, and the cost of this to biodiversity is not only through the direct loss of areas for mines, but also through the development of roads that further fragment the landscape, the leakage of heavy metals, and the destruction of limestone karsts, which represent global endemicity hotspots. Reservoir construction, wetland drainage, fires, pollution, invasive species, disease, and finally climate change are also considered. Once each issue has been discussed, the overall prognosis of regional biodiversity and priority actions to protect SE Asian biodiversity in the future is discussed. [ABSTRACT FROM AUTHOR]

Southeast-Asia ( SEA) constitutes a global biodiversity hotspot, but is exposed to extensive deforestation and faces numerous threats to its biodiversity. Climate change represents a major challenge to the survival and viability of species, and the potential consequences must be assessed to allow for mitigation. We project the effects of several climate change scenarios on bat diversity, and predict changes in range size for 171 bat species throughout SEA. We predict decreases in species richness in all areas with high species richness (>80 species) at 2050-2080, using bioclimatic IPCC scenarios A2 (a severe scenario, continuously increasing human population size, regional changes in economic growth) and B1 (the 'greenest' scenario, global population peaking mid-century). We also predicted changes in species richness in scenarios that project vegetation changes in addition to climate change up to 2050. At 2050 and 2080, A2 and B1 scenarios incorporating changes in climatic factors predicted that 3-9% species would lose all currently suitable niche space. When considering total extents of species distribution in SEA (including possible range expansions), 2-6% of species may have no suitable niche space in 2050-2080. When potential vegetation and climate changes were combined only 1% of species showed no changes in their predicted ranges by 2050. Although some species are projected to expand ranges, this may be ecologically impossible due to potential barriers to dispersal, especially for species with poor dispersal ability. Only 1-13% of species showed no projected reductions in their current range under bioclimatic scenarios. An effective way to facilitate range shift for dispersal-limited species is to improve landscape connectivity. If current trends in environmental change continue and species cannot expand their ranges into new areas, then the majority of bat species in SEA may show decreases in range size and increased extinction risk within the next century. [ABSTRACT FROM AUTHOR]

Migration is an essential ecological process, and is usually used to describe the seasonal movements between the breeding grounds and wintering areas. During migration, bird populations often disperse in groups and aggregate together due to geographical barriers, topography, seasonal climatic changes, species specific physiology, or other factors. Recording and reconstructing these diverse migratory routes are important for identifying major stopover sites as well as migration bottlenecks which may include key foraging grounds and resting areas, and ensuring high-quality habitat to provide adequate resources. However, good data including individual tracking data are only available for some regions and species large enough to carry a transmitter. Better approaches using observational data are needed to enable better understanding in less-studied regions. To reconstruct and visualize the long-distance avian migration routes with observations from the citizen-science dataset eBird, we developed an interpretive avian multi-trajectory reconstruction framework based on Level-order-Minimum-cost-Traversal (LoMcT) algorithm. This approach uses linear interpolation for missing records, spatial outlier detection for abnormal values, unsupervised clustering by density-based Mean-Shift algorithm for sub-group centroids, LoMcT algorithm based on the distances among centroids, and multi-trajectory reconstruction based on generalized additive models. We have verified the feasibility of our reconstruction method using 15 bird species, and analyzed the trends of the distribution density of birds' population during the long-distance migration cycle. Our analysis could help obtain the important gathering time points and sites in the moving process based on the multiple routes we reconstructed. These can be used in comparisons of multi-trajectory migration strategies between the transoceanic migratory birds and non-transoceanic ones, and provide the ability to understand how species are moving in the absence of individual tracking data to help target conservation better. We have demonstrated that the proposed approach is capable of reconstructing trajectories based on observational citizen-science data. • Multi-trajectory reconstruction for avian migration in population level with citizen science database. • Capturing the avian population dynamics performance during the migration circle. • Key foraging grounds and resting areas discovery. • Multi-trajectory migration strategies discussion between the transoceanic migratory birds and non-transoceanic ones. [ABSTRACT FROM AUTHOR]

We present the results of our tenth annual horizon scan. We identified 15 emerging priority topics that may have major positive or negative effects on the future conservation of global biodiversity, but currently have low awareness within the conservation community. We hope to increase research and policy attention on these areas, improving the capacity of the community to mitigate impacts of potentially negative issues, and maximise the benefits of issues that provide opportunities. Topics include advances in crop breeding, which may affect insects and land use; manipulations of natural water flows and weather systems on the Tibetan Plateau; release of carbon and mercury from melting polar ice and thawing permafrost; new funding schemes and regulations; and land-use changes across Indo-Malaysia. Highlights We present the 15 topics identified in our tenth annual horizon scan for global conservation. Scoring was carried out by a diverse group of experts using a Delphi-like process. Scores were based on the topics' novelty, likelihood, and potential for major impacts on biodiversity. Emerging themes include conservation impacts of biotechnological advances in agriculture. Other issues included climate change-induced release of carbon and mercury from polar ice. [ABSTRACT FROM AUTHOR]