Panda Research Articles

Habitat quality dynamics in China's first group of national parks in recent four decades: Evidence from land use and land cover changes

As the most biodiversity-rich part of the protected areas system, habitats within the pilot national parks have long been threatened by drastic human-induced land use and land cover changes. The growing concern about habitat loss has spurred China's national park project to shift from pilot to construction phase with the official establishment of China's first group of national parks (CFGNPs) in October 2021. But far too little attention has been paid to the synergistic work concerning the habitat quality (HQ) dynamics of all five national parks. Here, the InVEST model, combined with a satellite-derived land use and land cover product and a hot spot analysis (HSA) method, was used to investigate the HQ dynamics at the park- and pixel-scale within the CFGNPs. Our results demonstrate that the past ecological conservation practices within national parks have been unpromising, especially in Giant Panda National Park, Northeast China Tiger and Leopard National Park (NCTL), and Wuyi Mountain National Park (WYM), where HQ as a whole showed a significant decline. Furthermore, more than half of Hainan Tropical Rainforest National Park (87.2%), WYM (77.4%), and NCTL (52.9%) showed significant HQ degradation from 1980 to 2019. Besides, increasing trends in the area shares of HQ degraded pixels were observed in all five national parks from 1980–1999 to 2000–2019. The HSA implied that the hot spots of high HQ degradation rates tend to occur in areas closer to urban settlements or on the edge of national parks, where human activities are intensive. Despite these disappointing findings, we highlighted from the observed local successes and the HQ plateau that the construction of CFGNPs is expected to reverse the deteriorating HQ trends. Thus, we concluded our paper by proposing an HSA-based regulatory zoning scheme that includes five subzones to guide the future construction of China's national park system.

Automatically detecting the wild giant panda using deep learning with context and species distribution model

The giant panda is a flagship species in ecological conservation. The infrared camera trap is an effective tool for monitoring the giant panda. Images captured by infrared camera traps must be accurately recognized before further statistical analyses can be implemented. Previous research has demonstrated that spatiotemporal and positional contextual information and the species distribution model (SDM) can improve image detection accuracy, especially for difficult-to-see images. Difficult-to-see images include those in which individual animals are only partially observed and it is challenging for the model to detect those individuals. By utilizing the attention mechanism, we developed a unique method based on deep learning that incorporates object detection, contextual information, and the SDM to achieve better detection performance in difficult-to-see images. We obtained 1169 images of the wild giant panda and divided them into a training set and a test set in a 4:1 ratio. Model assessment metrics showed that our proposed model achieved an overall performance of 98.1% in mAP0.5 and 82.9% in recall on difficult-to-see images. Our research demonstrated that the fine-grained multimodal-fusing method applied to monitoring giant pandas in the wild can better detect the difficult-to-see panda images to enhance the wildlife monitoring system.

Quantifying the Evolution of Giant Panda Habitats in Sichuan Province under Different Scenarios

The giant panda (Ailuropoda melanoleuca) is a relic species in China and a flagship species in the field of endangered wildlife conservation. The conservation of the giant panda’s habitat has gained widespread attention for this reason. Historically, Chinese Giant Panda Nature Reserves are surrounded by communities and the resource utilization behavior of households disturbs the giant panda habitat. Changes in these communities and in Giant Panda Nature Reserves began around 2010, with the feminization and aging of the farm labor force. These changes brought different resource utilization behaviors that led to different evolutionary tendencies in giant panda habitats. This research study assesses the impact of these tendencies based on data from the fourth survey of the giant panda in the Sichuan Province and from geographic information data. The paper aims to uncover the internal mechanisms of farmers’ resource utilization behavior in terms of the changes wrought to giant panda habitats. The paper simulates the future habitat of the giant panda based on the LUCC (land use/cover change) model to identify anticipated changes in future landscape patterns and the habitat quality of giant pandas under the current scenarios. The paper analyzes the spatial-temporal change of landscape patterns through the land use transfer matrix, based on the Markov model. The results of the scenario analyses illustrate the spatial and temporal difference in habitat quality. The driving mechanism for landscape pattern change is explored using the logistic regression model. The paper simulates the variation tendency of giant panda habitats under differential labor force structures and resource utilization behavior based on the CA (cellular automata) model, with the robustness of the results verified by participatory experiment. Through four scenarios of simulated farm labor force structure and resource utilization behavior, results suggest that the quality of giant panda habitats in the future will be relatively high when workforce feminization and aging is intense and resource utilization behavior is weakened. The simulated results confirm that the current agricultural labor force structure can reduce the intensity of resource utilization behavior. In this scenario, disturbance to giant panda habitats would decrease and their quality would improve.

Whole genome bisulfite sequencing reveals DNA methylation roles in the adaptive response of wildness training giant pandas to wild environment.

DNA methylation modification can regulate gene expression without changing the genome sequence, which helps organisms to rapidly adapt to new environments. However, few studies have been reported in non-model mammals. Giant panda (Ailuropoda melanoleuca) is a flagship species for global biodiversity conservation. Wildness and reintroduction of giant pandas are the important content of giant pandas’ protection. However, it is unclear how wildness training affects the epigenetics of giant pandas, and we lack the means to assess the adaptive capacity of wildness training giant pandas. We comparatively analyzed genome-level methylation differences in captive giant pandas with and without wildness training to determine whether methylation modification played a role in the adaptive response of wildness training pandas. The whole genome DNA methylation sequencing results showed that genomic cytosine methylation ratio of all samples was 5.35%–5.49%, and the methylation ratio of the CpG site was the highest. Differential methylation analysis identified 544 differentially methylated genes (DMGs). The results of KEGG pathway enrichment of DMGs showed that VAV3, PLCG2, TEC and PTPRC participated in multiple immune-related pathways, and may participate in the immune response of wildness training giant pandas by regulating adaptive immune cells. A large number of DMGs enriched in GO terms may also be related to the regulation of immune activation during wildness training of giant pandas. Promoter differentially methylation analysis identified 1,199 genes with differential methylation at promoter regions. Genes with low methylation level at promoter regions and high expression such as, CCL5, P2Y13, GZMA, ANP32A, VWF, MYOZ1, NME7, MRPS31 and TPM1 were important in environmental adaptation for wildness training giant pandas. The methylation and expression patterns of these genes indicated that wildness training giant pandas have strong immunity, blood coagulation, athletic abilities and disease resistance. The adaptive response of giant pandas undergoing wildness training may be regulated by their negatively related promoter methylation. We are the first to describe the DNA methylation profile of giant panda blood tissue and our results indicated methylation modification is involved in the adaptation of captive giant pandas when undergoing wildness training. Our study also provided potential monitoring indicators for the successful reintroduction of valuable and threatened animals to the wild.

Microsporum gypseum Isolated from Ailuropoda melanoleuca Provokes Inflammation and Triggers Th17 Adaptive Immunity Response.

Microsporum gypseum causes dermatomycoses in giant pandas (Ailuropoda melanoleuca). This study aimed to investigate the immune response of M. gypseum following deep infection. The degree of damage to the heart, liver, spleen, lungs, and kidneys was evaluated using tissue fungal load, organ index, and histopathological methods. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) detected the mRNA expression of receptors and cytokines in the lung, and immunofluorescence staining and flow cytometry, were used to assess immune cells in the lung. The results indicated that conidia mainly colonized the lungs and caused serious injury with M. gypseum infection. Furthermore, dectin-1, TLR-2, and TLR-4 played a role in recognizing M. gypseum cells. Numerous inflammatory cells, mainly macrophages, dendritic cells, polymorphonuclear neutrophils, and inflammatory cytokines (TGF-β, TNF-α, IL-1β, IL-6, IL-10, IL-12, and IL-23), were activated in the early stages of infection. With the high expression of IL-22, IL-17A, and IL-17F, the Th17 pathway exerted an adaptive immune response to M. gypseum infection. These results can potentially aid in the diagnosis and treatment of diseases caused by M. gypseum in giant pandas.

Giant pandas' staple food bamboo phyllosphere fungal community and its influencing factors.

Giant pandas have developed a series of foraging strategies to adapt to their special bamboo diets. Although bamboo is an important food resource for giant pandas in Liziping National Nature Reserve (Liziping NR), China, there are relatively few studies on their phyllosphere fungal community and its influencing factors. Herein, we used ITS1 amplification and metagenomic sequencing to analyze the phyllosphere fungi diversity and functions (KEGG, CAZyme, and antibiotic resistance gene) and explore the influencing factors for the three giant pandas foraging bamboo species (Arundinaria spanostachya, AS; Yushania lineolate, YL; and Fargesia ferax, FF) over different seasons (spring vs. autumn) in Liziping NR, China. We found that Ascomycota and Basidiomycota were the most dominant phyla in the bamboo phyllosphere. The alpha diversity (e.g., the Sobs index and Shannon index) was relatively higher in autumn samples than in spring samples, and the community structure differed significantly between the three bamboo species in spring and autumn. Some biotic and abiotic variables (e.g., the elevation and mean base diameter of bamboo) significantly influenced the abundance, diversity, and community structure of the bamboo phyllosphere fungal community. Moreover, the functional analysis showed the differences in the glycoside hydrolase community and antibiotic resistance gene (ARG) profile between spring and autumn samples. Co–occurrence network modeling suggested that AS phyllosphere fungal communities in autumn employed a much more complex network than that in spring, and the abundance of multidrug, tetracycline, and glycopeptide resistance genes was high and closely correlated with other ARGs. These results indicate that fungal community’s abundance, diversity, and community structure are mainly affected by the season, host species, and elevation. The season and host species are major factors affecting the biological functions (KEGG and CAZyme), ARGs, and interactions between sympatric bacterial and fungal communities in bamboo phyllosphere. This integrated study can provide a reference basis for the seasonal management of bamboo resources foraged by wild giant pandas, and predict the risk of antibiotic resistance in bamboo phyllosphere fungal flora in Liziping NR (Xiaoxiangling mountains), China.

Lipidomics for Determining Giant Panda Responses in Serum and Feces Following Exposure to Different Amount of Bamboo Shoot Consumption: A First Step towards Lipidomic Atlas of Bamboo, Giant Panda Serum and Feces by Means of GC-MS and UHPLC-HRMS/MS.

Lipidic metabolites play essential roles in host physiological health and growth performance, serving as the major structural and signaling components of membranes, energy storage molecules, and steroid hormones. Bamboo, as wild giant pandas’ exclusive diet, is the main determinant of giant pandas’ lipidome, both as a direct source and through microbiota activity. Interestingly, the consumption of bamboo has attracted little attention from a lipidomic perspective. In the current study, we outline the lipidomic atlas of different parts of bamboo. By gas chromatography—mass spectrometry (GC-MS), we have been able to obtain the absolute quantification of 35 fatty acids pertaining to short chain fatty acids (8), medium chain fatty acids (6), long chain fatty acids (17), and very long chain fatty acids (4), while liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS) allowed us to obtain the relative quantification of another 1638 lipids. Among the fatty acids quantified in absolute terms, eight showed significantly distinct concentrations among different bamboo parts. Subsequently, we investigated how the giant panda’s serum and fecal lipidome adapt to the most important annual change in their diet, represented by the consumption of high amounts of bamboo shoots, typical of spring, the weight-gaining season. Five fatty acids were significantly altered in feces and two in serum, respectively, due to the different levels of bamboo shoot consumption. Furthermore, significant differences of the main bacteria strains were observed in feces between the two groups at the genus level, pertaining to Streptococcus, Leuconostoc, and Vagococcus. Correlations between giant panda fecal microbiome and lipidome were evaluated by Pearson correlation analysis. These findings suggest that a balanced diet, important for the overall lipidomic function and giant panda health, could be reached even in this remarkable case of a single food-based diet, by administering to the giant panda’s combinations of different parts of bamboo, with specific lipidome profiles.

Possible Effects of Early Maternal Separation on the Gut Microbiota of Captive Adult Giant Pandas.

Simple SummaryIn the process of ex-situ conservation, young giant pandas face a variety of unfavorable environmental impacts such as frequent maternal separation, parenting by non-parents, noise from tourists, and frequent replacement of animal houses, which may cause psychological and physiological stress. The gut microbiota is an important carrier of the interaction between the body and the environment, and recent studies revealed an association between stress and alterations of the intestinal microbiota. So, is the stress caused by the unfavorable parenting environment in the early life of captive giant pandas related to the gut microbiota? To answer this question, we use fecal metagenomics and LC-MS technology to study the effect of different parenting patterns on the structure, diversity, and metabolites of the intestinal microbial community of captive giant pandas. In order to evaluate the possible adverse effects of the traditional parenting mode on the gut microbiota of captive giant pandas in the early life, it can provide an important scientific basis for improving the welfare level of captive giant pandas.Maternal deprivation (MD) in early life induces dysbiosis in the host gut microbiota, which is a key determinant of abnormal behavior in stress model individuals. Compared with the early parenting environment of the wild, captive giant pandas face frequent and premature maternal separation. Will this lead to imbalance in intestinal flora and stress in captive giant pandas? The purpose of this research is to evaluate the possible adverse effects of the traditional parenting mode on the gut microbiota of captive giant pandas. The results showed that the frequent and premature maternal separation at early stages of the young did not change α and β diversity indices of the gut microbes, but it increased the relative abundance of s_Clostridium_tetani and s_Clostridium_sp_MSJ_8 (significantly positively correlated with the metabolism of propionic acid) and also the concentrations of fecal metabolites that are related to stress (N-acetyl-l-aspartic acid and corticosterone) in the intestinal tract of giant pandas in adulthood. Thereby, the function of protein digestion and absorption in the intestines of captive giant pandas was decreased, and the metabolism of short-chain fatty acids was disturbed. In conclusion, the parenting experience of early maternal separation could adversely affect the stress caused by the unfavorable parenting environment in the early life of captive giant pandas related to the gut microbiota of the captive giant pandas in adulthood.

Have protected areas in China achieved the ecological and economic “win-win” goals? Evidence from the Giant Panda Reserves of the Min Mont Range

Evaluating the effectiveness of conservation policies is a primary means in support of continued expansion and improved management of protected areas (PAs) for wildlife. This study assesses the ecological and economic effectiveness of giant panda PAs in the Mont Min Range of southwest China, by taking advantage of the cutting-edge impact evaluation methods and a large panel dataset derived from remote sensing images, GIS data, and socioeconomic statistics. Our results show that the most prominent effects are the increase in giant panda activities, the improvement of forest cover, the development of ecotourism and environmentally friendly agriculture, and the growth of farmer income. Also, the PAs have not caused ecological damage and poverty to undesignated areas outside of them. Meanwhile, they have not enhanced the growth of bamboo resources nor mitigated the threat of intense human pressures. Overall, the PAs have thus achieved a “win-win” outcome. Our study contributes to improved understanding and action of wildlife conservation not only for China but also for many other parts of the world.

A novel cysteine protease inhibitor in Baylisascaris schroederi migratory larvae regulates inflammasome activation through the TLR4–ROS–NLRP3 pathway

BackgroundGiant pandas (Ailuropoda melanoleuca) are the obligate host of the parasitic roundworm Baylisascaris schroederi. The infection of giant pandas with B. schroederi is very common. At present, little is known about the mechanism of immune interaction between B. schroederi and the host. As an important component of innate immunity, the NOD-like receptor 3 (NLRP3) inflammasome plays an important role in host immune response and the occurrence and development of infectious diseases.MethodsWe analyzed the regulation of NLRP3 inflammasome activation in monocyte-derived macrophages (MDMs) by the recombinant B. schroederi migratory larvae cysteine protease inhibitor rBsCPI-1, knowing from a previous study that the CPI-1 is highly expressed in B. schroederi migratory larvae. We first determined the effects of rBsCPI-1 and excretory–secretory products of B. schroederi migratory larvae on cell proliferation using the CCK-8 and LDH release assays. We then analyzed NLRP3 inflammasome activation, pyroptosis and pro-inflammatory cytokine release by quantitative-PCR, western blotting and enzyme-linked immunosorbent assay. The signaling pathway of rBsCPI-1 to activate NLRP3 inflammasomes was analyzed in activation and inhibition experiments. Finally, the effects of rBsCPI-1 on inflammasome activation in mice immunized with rBsCPI-1 were analyzed.ResultsThe activation and inhibition experiments revealed that rBsCPI-1 induced inflammasome activation through the TLR4–ROS–NLRP3 signaling pathway, with reactive oxygen species (ROS) not only functioning as an activator of the NLRP3 inflammasome, but also an activation product of the NLRP3 inflammasome. rBsCPI-1 promoted the activation and assembly of the NLRP3 inflammasome, which further converted the pro-inflammatory cytokines interleukin (IL)-1β and IL-18 into mature active forms. At the same time, caspase-1 cleaved gasdermin D to trigger cell pyroptosis. The results of animal immunization experiments further confirmed that rBsCPI-1 could induce the activation of the NLRP3 inflammasome.ConclusionsrBsCPI-1 activates the inflammasome through the TLR4–ROS–NLRP3 signaling pathway and further induces the pyroptosis of MDMs and release of pro-inflammatory factors IL-1β and IL-18, thus promoting the occurrence and development of the inflammatory response in the host.Graphical abstract

Examining Social Equity in the Co-Management of Terrestrial Protected Areas: Perceived Fairness of Local Communities in Giant Panda National Park, China

Social equity is imperative both morally and instrumentally in the governance of protected areas, as neglecting this consideration can result in feelings of injustice and thus jeopardize conservation objectives. Despite the progressive attention paid to conservation equity, few have linked it with co-management arrangements, especially in the context of terrestrial protected areas. This study assesses the fairness perceptions in China’s Giant Panda National Park from recognitional, procedural, and distributional dimensions, to further disclose their correlations with individuals’ characteristics and participation in co-management activities. The regression analysis shows that all co-management types (instruction, consultation, agreement, and cooperation) are significantly linked with certain directions of perceived social equity. One novel finding here is that alternative types of co-management activities are influencing social equity in different ways. In addition, our research discloses the effects of education across all equity categories, and location is merely significantly related to recognitional equity. These findings suggest more inclusive and empowered co-management endeavors to strive for more equitably managed protected areas. Crucial steps to advance this include extending participative channels, co-producing better compensation plans, strengthening locals’ conservation capabilities, etc. Herein, this study appeals to a greater focus on social equity issues in co-management regimes, and tailored actions should be taken to tackle specific local problems.

Nutritional and physical characteristics evaluation of giant panda (Ailuropoda melanoleuca) milk in comparison with bovine and caprine milk

The odour, particle size distribution, microstructure and nutrient profile of giant panda milk (GPM) was compared with bovine milk (BM) and caprine milk (CM). SDS-PAGE images of GPM showed clear, deep and uncertain bands different from those for BM and CM. GPM displayed significantly higher levels for free amino acids (p < 0.05), as well as more polyunsaturated and monounsaturated fatty acids. An electronic nose distinguished the three samples; GPM had the strongest response values to sensors. The effective diameter and polydispersity index of GPM were significantly higher than BM and CM (p < 0.05), and the same results were also observed in confocal laser scanning microscopy (CLSM) images. A giant panda milk substitute formulation with the following main nutrients is recommended: protein, 36%; fat, 50%; carbohydrates, 8%. It is also necessary to supplement a small quantity of isoglobotriose, and adjust the milk substitute amino acids and fatty acids ratios.

Impacts of climate change on the distributions and diversity of the giant panda with its sympatric mammalian species

It is widely accepted that anthropogenic climate change is driving species redistribution globally, which would potentially lead to a reshuffling of ecological communities worldwide. Here, we used tuned MaxEnt models to forecast range shifts, changes in species richness and species turnover of the giant panda with its 22 sympatric mammalian species under different future climate change scenarios. We found that more than 78% of these mammalian species will experience range contraction under all future scenarios, and importantly, at least three species were predicted to lose more suitable habitat than the giant pandas. We also predicted net losses of mammalian species under future climate change. In particular, the greatest species richness declines mainly occur in Daxiangling and Liangshan mountains, with high species losses and low species gains. Similarly, we found that the strongest species turnovers mainly occur in Qionglai and Liangshan mountains. Our findings highlight that future climate change will pose a major threat to the distribution and diversity of the giant panda with its sympatric mammalian species, challenging the effectiveness of using umbrella species to guide ecosystem conservation and management under climate change. Therefore, a more holistic ecosystem protection strategy, rather than the single-species rescue approach, should be implemented to protect mammal communities in a changing world.

Special architecture and anti-wear strategies for giant panda tooth enamel: Based on wear simulation findings.

Giant pandas are the flagship species in world conservation. Due to bamboo being the primary food source for giant pandas, dental wear is common owing to the extreme toughness of the bamboo fiber. Even though research on tooth enamel wear in humans and domestic animals is well-established, research on tooth enamel wear in giant pandas is scarce. The purpose of this study is to evaluate tooth enamel wear resistance in giant pandas to provide a basis for a better understanding of their evolutionary process. From microscopic and macroscopic perspectives, the abrasion resistance of dental enamel in giant pandas is compared with that of herbivorous cattle and carnivorous dogs in this study. This involves the use of micro-scratch and frictional wear tests. The results show that the boundary between the enamel prism and the enamel prism stroma is well-defined in panda and canine teeth, while bovine tooth enamel appears denser. Under constant load, the tribological properties of giant panda enamel are similar to those of canines and significantly different from those of bovines. Test results show that the depth of micro scratches in giant panda and canine enamel was greater than in cattle, with greater elastic recovery occurring in dogs. Scratch morphology indicates that the enamel substantive damage critical value is greater in pandas than in both dogs and cattle. The analysis suggests that giant panda enamel consists of a neatly arranged special structure that may disperse extrusion stress and absorb impact energy through a series of inelastic deformation mechanisms to cope with the wear caused by eating bamboo. In this study, the excellent wear resistance of giant panda's tooth enamel is verified by wear tests. A possible theoretical explanation of how the special structure of giant panda tooth enamel may improve its wear resistance is provided. This provides a direction for subsequent theoretical and experimental studies on giant panda tooth enamel and its biomaterials.

Space use and microhabitat selection of wild giant pandas in Meigu Dafengding National Nature Reserve, China

The giant panda (Ailuropoda melanoleuca) is a special rare and endangered species in China and is the flagship species for global biodiversity conservation. This study used different methods including Kernel density, statistical analysis, and logistic regression analysis to investigated the spatial distribution, migration in different seasons and different distribution areas, as well as the foraging patch selection strategies of wild giant pandas in Meigu Dafengding National Nature Reserve in the Liangshan Mountains. The results demonstrated that, in the study area, giant pandas were mainly distributed in the Wahei-Yizi Yakou Habitat Corridor with an activity area of 144.93 km2, which accounted for 28.59% of the whole reserve. The core distribution area of the species was 92.07 km2 and the population density was 0.24 pcs km–2. There were two significant seasonal domains for the activities of giant pandas: the low-altitude winter habitat of Yushania maculata Yi and Yushania ailuropodina Yi bamboo species, as well as the high-altitude summer habitat of Bashania fangiana species. With seasonal changes, giant pandas migrated among different bamboo distribution regions. Giant pandas were mainly distributed in high-altitude areas that had secondary forest, tall trees with a large diameter at breast height (DBH) and bamboo forest. The spatial distribution pattern and microhabitat selection of giant pandas in Meigu Dafengding National Nature Reserve were determined. The findings of this study provide scientific implications for the local conservation and management of the habitat of wild giant pandas.

The fate of giant panda and its sympatric mammals under future climate change

Assessing the vulnerability of biodiversity under global climate change is one of the major tasks in ecology and conservation biology. Although species' vulnerability to climate change depends on habitat exposure, species sensitivity and adaptability, multifaceted studies on the impacts of climate change on biodiversity are still lacking. The aim of this study was to fill this gap by assessing the vulnerability of giant panda with its sympatric mammal species in Sichuan province of China, through the climate niche factor analysis. We found that species sensitivity plays a greater role than habitat exposure in determining the vulnerability of these species under future climate change, which doesn't closely match their current conservation status. Besides, these mammals were predicted to be more vulnerable at lower altitudes or latitudes. In particular, Daxiangling and Liangshan mountains emerge as the most vulnerable places to climate change. The conservation gap analysis demonstrated that the current protected area network covers no more than 5 % of the most vulnerable areas. Together, these results highlight the importance of using multifaceted analyses by integrating species sensitivity and habitat exposure to assess climate-related risks to better inform biodiversity conservation and management.

Will the Experience of Human–Wildlife Conflict Affect Farmers’ Cultivated Land Use Behaviour? Evidence from China

Effectively managing and mitigating “human–wildlife conflict” (HWC) by adjusting the use of cultivated land to realise the coexistence of humans and wildlife plays an important role in protecting biodiversity, ensuring food security, improving cultivated land use efficiency, and improving the livelihoods of community residents in nature reserves. Based on the “harmful experience–expectation change–behavioural adjustment” theoretical analysis framework and survey data on 1008 farmers in China’s Giant Panda National Park, this paper uses a binary logit model and a mediating utility model to analyse the effect of HWC experience on the cultivated land use of farmers and the action mechanisms. The results show the following: (1) HWC experience increases the probability that farmers’ cultivated land use behaviour will be adjusted, which will not only increase the probability that farmers’ planting structure of cultivated land will be adjusted but also increase the probability that farmers will abandon cultivated land. (2) Farmers in the national park have a higher probability of adjusting their cultivated land use behaviour after experiencing HWCs than those outside the national park. Farmers in the national park mainly prefer to adjust the planting structure, while farmers outside the park are more inclined to abandon cultivated land. (3) Low-income farmers are more likely to adjust their cultivated land use behaviour after experiencing HWCs than high-income farmers. The low-income group mainly tends to adjust the planting structure of cultivated land, while the high-income group is more inclined to directly abandon cultivated land. (4) The farmers in the group with a high degree of dependence on cultivated land for their livelihood have a higher probability of adjusting their cultivated land use behaviour after experiencing HWC than those in the low-dependency group, and they tend to adjust the planting structure. (5) HWC experience mainly improves farmers’ adjustment of cultivated land use behaviour by improving their awareness of future risks of HWC. In other words, “HWC” will change the behavioural decision-making of farmers and the differences in constraints, such as different regions and different income levels, will lead to differences in “HWC” affecting farmers’ behaviours. The conclusions of this paper not only help in understanding the adjustment mechanism of farmers’ cultivated land use behaviour in the context of HWCs but also provide a decision-making reference for actively changing cultivated land use methods to address HWCs.

Ursids evolved early and continuously to be low-protein macronutrient omnivores

The eight species of bears world-wide consume a wide variety of diets. Some are specialists with extensive anatomical and physiological adaptations necessary to exploit specific foods or environments [e.g., polar bears (Ursus maritimus), giant pandas (Ailuropoda melanoleuca), and sloth bears (Melursus ursinus)], while the rest are generalists. Even though ursids evolved from a high-protein carnivore, we hypothesized that all have become low-protein macronutrient omnivores. While this dietary strategy has already been described for polar bears and brown bears (Ursus arctos), a recent study on giant pandas suggested their macronutrient selection was that of the ancestral high-protein carnivore. Consumption of diets with inappropriate macronutrient profiles has been associated with increased energy expenditure, ill health, failed reproduction, and premature death. Consequently, we conducted feeding and preference trials with giant pandas and sloth bears, a termite and ant-feeding specialist. Both giant pandas and sloth bears branched off from the ursid lineage a million or more years before polar bears and brown bears. We found that giant pandas are low-protein, high-carbohydrate omnivores, whereas sloth bears are low-protein, high-fat omnivores. The preference for low protein diets apparently occurred early in the evolution of ursids and may have been critical to their world-wide spread.

Impacts of Japanese Larch Invasion on Soil Bacterial Communities of the Giant Panda Habitat in the Qinling Mountains

Japanese larch (Larix kaempferi), a non-native tree species, has been widely planted in the Qinling Mountains since the last century, but it does not meet the habitat needs of giant pandas (Ailuropoda melanoleuca), mainly because of food, further causing habitat degradation and fragmentation. However, how soil microorganisms, considered as predictors of the soil environment, respond to Japanese larch remains poorly explored, especially compared with native forests. Here, we collected 40 soil samples from plantation, bamboo, and natural (excluding bamboo) forests in the Changqing Nature Reserve and Foping Nature Reserve in Qinling to compare soil bacterial community composition and diversity using high-throughput sequencing of bacterial 16S rRNA genes. The soil chemical properties and bacterial communities differed noticeably under forest-type classification patterns. The soil of the Japanese larch planted forests underwent substantial degradation, with higher acidity, lower alpha diversity, and more significant enrichment in the oligotrophic bacteria Acidobacteria and Verrucomicrobia, in contrast to the other two primary forests with elevated soil nutrient levels. The application of PICRUSt2 indicated the down-regulation of amino acid-related metabolism in planted forests. Moreover, pH was the primary factor determining the whole bacterial community structures. To avoid the uncertainty of a single sampling region, we chose different sampling sites that could be considered as geographical factors, possibly due to environmental heterogeneity or dispersal limitations, which also explained the specific community patterns of microorganisms. Overall, this paper may help provide a scientific basis for future revegetation in giant panda habitats, highlighting the urgent need for ecological restoration and sustainable forestry management.

The effectiveness of a large protected area to conserve a global endemism hotspot may vanish in the face of climate and land-use changes

Endemic vertebrates are a crucial component of biodiversity, yet face disproportionally high extinction risk as climate and land-use changes drive habitat loss. Large protected areas are therefore deemed necessary to mitigate biodiversity loss. In 2021, China’s Giant Panda National Park (GPNP, 27,134 km2) was established in one of the global endemism hotspots. In this study we ask the question whether this large national park is able to conserve the many threatened endemic vertebrates occurring in the region in the face of climate and land-use changes, in order to assess the long-term effectiveness of the GPNP. We used species distribution modeling techniques to project the distributions of 40 threatened terrestrial (and freshwater) endemic vertebrates under land-use and climate change scenarios SSP2–4.5, SSP3–7.0 and SSP5–8.5 in 2081–2100, and assessed the extent to which their distributions are covered by the GPNP, now and in the future. We found that by 2081–2100, two thirds of the threatened endemic vertebrates are predicted to lose part (15–79%, N = 4) of or (nearly) their entire (80–100% loss, N = 23) range under all three climate and land-use change scenarios. Consequently, fewer species are predicted to occur in the GPNP than at present. Our findings confirm the high vulnerability of threatened endemic species to climate and land-use changes, despite protected areas. Habitat loss due to climate and land-use changes elevate extinction risk of species in endemism hotspots across the globe. Urgent, widespread and intensified mitigation measures and adaptation measures are required at a landscape scale for effective conservation efforts in the future.