How large-scale patterns of species diversity emerge is a central yet controversial issue in ecology and biogeography. Despite the long history of studies the mechanisms driving species diversity patterns in space remain poorly known. Using distribution data of all gymnosperm species in China, we assessed the influence of environmental factors on spatial patterns of species diversity in China. Further, we evaluated the proportion of gymnosperms in local floras. We found that species diversity of gymnosperms decreases along a south-north axis. Hengduan Mountains, with the highest species diversity, is a hotspot of gymnosperms. Species diversity patterns differ significantly between the gymnosperm subclasses. In particular, the species diversity pattern of Pinidae is similar to that of all species combined, while the species diversity of Gnetidae is highest in the drylands of northwestern China. In contrast, Cycadidae is restricted to southern China. Environmental heterogeneity and precipitation are the best predictors of species diversity patterns of all gymnosperms combined, followed by temperature anomaly since the Last Glacial Maximum (LGM), elevational range and energy. That different factors predict species diversity patterns of different gymnosperm subclasses, may reflect the differences in their evolutionary history and physiological adaptions. The ratio of gymnosperm to angiosperm species diversity is lower in the warm and humid eastern and southern parts of China, and increases towards the drylands in western and northern parts. Environmental energy and precipitation were good predictors of the ratio of gymnosperms to angiosperms. Specifically, the ratio decreases with increase of energy and decrease of precipitation suggesting that angiosperms may have stronger competitive ability in warm and humid regions while gymnosperms adapt better to dry and cold environments.

To explore the composition and interannual dynamics of tree seedlings in the montane region of eastern Liaoning Province in China, we established 1,600 seedling quadrats of size 5 m × 5 m (25 m²) within a 4-ha plot to monitor forest dynamics. We analyzed species composition, height-class structure, interannual dynamics and spatial distribution of tree seedlings from three censuses (2014 to 2016). We recorded a total of 22 species of tree seedlings during the survey period. The species composition of tree seedlings did not vary significantly among years, but varied greatly among quadrats. Species that dominated as seedlings largely reflected the dominant species among adults. Tree seedling numbers varied significantly among different tree species across years, with Fraxinus rhynchophylla, Acer mono and Juglans mandshurica accounting for 75.6% of the total seedlings in the three censuses. The abundances of F. rhynchophylla and J. mandshurica seedlings varied greatly among three years, while the other species varied little. Similarly, seedling density also varied greatly among different species. We also found interspecific and interannual variation in new seedling recruits and those that died. Recruit abundance during 2014-2015 (3,888) was higher than 2015-2016 (1,710), and the seedling mortality rate was also higher in 2014-2015 (23.7%) than 2015-2016 (12.7%). The mortality rate of recruited seedlings (18.8%) was higher than that of existing seedlings (8.1%) during 2015-2016. Finally, we found that the dominant seedlings showed spatially clustered distributions and the spatial pattern of seedling distributions was consistent with that of adults of the species.

Global climate change will alter temporal and spatial distributions of precipitation patterns. The effects of precipitation changes on crop seed germination and growth have been previously investigated, however, there has been limited research on effects of precipitation changes on how invasive weeds compete with crops. Exploring competition between exotic weeds and native crops under different annual precipitation patterns and cultivation modes will provide a theoretical basis to control alien weeds with impending changes to the global climate. In this study, we assessed how precipitation alters competitive dynamics between two plants, Amaranthus retroflexus, a widespread invasive weed in agricultural ecosystem in Northeastern China, and Glycine max, one of the most important native crops in China. We conducted pot experiments under three patterns of annual precipitation: the average annual precipitation pattern (the average total precipitation amount of growing season of the recent 30 years), the deficient annual precipitation pattern (20% lower than the average value), and the plentiful annual precipitation pattern (20% higher than the average value). The pots were placed underneath a rainout shelter, and the two plants were seeded as two plants of the same species per pot (sole species) or two plants of different species per pot (mixed species). We found that the plant height and total biomass of A. retroflexus and G. max in the average precipitation annual pattern were higher than those of deficient precipitation annual pattern, but lower than those of the abundance precipitation annual pattern. The root to shoot ratio of the two plants at the early growing season were all highest in the deficient precipitation annual pattern, indicating that both plants could adapt to the arid environment by increasing the root biomass allocation and decreasing the shoot biomass allocation. Under all the annual precipitation patterns, plant height, relative growth rate and total biomass of mixture G. max were significantly less than sole planted G. max, while A. retroflexus showed the opposite trend. These results indicate that interspecific competition significantly inhibited the growth of G. max, but promoted the growth of A. retroflexus, suggesting asymmetric competition between the species. In general, the competitive ability of G. max increased with higher precipitation, while that of A. retroflexus increased when precipitation declined. The results indicated that A. retroflexus can successfully invade G. max cropland under all three precipitation scenarios, and maintain a high plant height, relative growth rate, and biomass over a wide range of annual precipitation variation. These biological characters of A. retroflexus may allow it to become a successfully globally invasive weed, and drought may favor its invasion of G. max cropland.

Firmiana danxiaensis is an endemic plant species which is narrowly distributed in the northern parts of Shaoguan, Guangdong, China. To devise appropriate conservation strategies for this rare species, we examined the population structure and estimated the demographic history of nine natural populations using 18 EST-SSR markers. The results revealed a moderate degree of total genetic diversity (Ht = 0.631) at the species level but high genetic diversity within populations (Hs = 0.546). Strong genetic differentiation existed between two groups of Danxiashan and Nanxiong (F_ST = 0.150). This current pattern might have arisen from prolonged geographical isolation and human disturbances. STRUCTURE analysis demonstrated that whole population can be divided into two distinct gene pools, closely related by their geographic location and having experienced independent evolutionary routes. The genetic background of Danxiashan was more complicated than that of Nanxiong. Approximate Bayesian Computation (ABC) analysis indicated that divergence time between the two groups could be 100,000 years BP, and their effective population size were 7,290 and 5,550 individuals, respectively. Combining the information of genetic variation with niche modelling, we inferred that F. danxiaensis might have been widely distributed around the Nanling Mountain in the Quaternary period. Populations located in the northern of Nanling Mountain likely became extinct due to climate change. Danxiashan and Nanxiong provided the main refuges for the species during the last ice age. Being a rare species with small population sizes, better ecological investigation of natural populations and in situ conservation and implementation of restoration strategy are important measures to conserve this species.

Understanding spatial distribution and habitat overlap of sympatric species is essential to developing integrated policies for conserving species and regional biodiversity. This study combined data from the 4th National Survey of giant panda (Ailuropoda melanoleuca) and long-term field survey. We used the Maximum entropy model (MaxEnt) to predict the distributions of two sympatric bears, the giant panda and Asiatic black bear (Ursus thibetanus) in Liangshan Mountains. Based on spatial distribution of two species, we measured habitat fragmentation and spatial overlap of habitat use, and assessed environmental requirements of both species. Our results indicated that: (1) both species had similar distributions of suitable habitats, both were mainly distributed on the ridges of Liangshan Mountains. The suitable habitat area of giant panda and black bear were 1,383.84 km² and 2,411.49 km², respectively. (2) The habitats of both species were fragmented and separated into many patches. However, habitat connectivity for the black bear was better than for giant panda. (3) Niche overlap indices, calculated by ENMTools, showed that two species have high overlap in their ecological niche (D = 0.654 and I = 0.901). The overlapping habitat comprised 958.29 km² of the study area, which contained 69.25% of giant panda habitat and 39.74% of black bear habitat. (4) We used permutation techniques to estimate the importance of environmental variables in the MaxEnt model. Distance to residents and altitude were the most influential predictors for both species. Vegetation types and mean temperature of coldest quarter were the third and fourth important predictor for giant panda, while annual maximum enhanced vegetation index (EVI) and distance to roads was important for the black bear. To protect these two species more effectively, a series of measures have to be adopted, such as strengthening vegetation restoration, controlling disturbance, and enhancing connectivity between habitat patches. We recommend that a systematic, multi-species conservation plan should be developed.

We evaluated the environmental safety of the transgenic RRM2 (RNA recognition motif 2) cotton on insect communities in the Changjiang River Ecological Zone. From 2013 to 2015, we recorded and systematically monitored the structure and composition, community characteristics, diversity, abundances and seasonal changes of the insect community, pest sub-community and natural enemy sub-community in the transgenic cotton fields. We found that the composition of main functional groups in transgenic cotton fields was similar to non-transgenic cotton fields. The transgenic RRM2 cotton fields had significantly higher aphid numbers than non-transgenic cotton field in 2013. In comparison, the number of cotton spider mite, cotton bollworm and other Lepidoptera were markedly lower in transgenic RRM2 cotton field than in non-transgenic cotton field in 2013. There was no significant difference in the other two years and other functional groups. We also found that abundances of insects increased, but species richness decreased, in the transgenic RRM2 cotton fields compared to the non-transgenic cotton fields during pest outbreak years. However, there was little difference of individual numbers and species richness of insect community in transgenic RRM2 cotton fields relative to non-transgenic one, but differed significantly during three years. Indices of diversity, evenness and dominance of insect community and pest sub-community did not vary by cotton type during years, the same as that of natural enemy sub-community except for that in 2013. Although there were seasonal fluctuations in the number of individuals and community characteristics of insect community, pest sub-community and natural enemies, these temporal dynamics did not vary between the RRM2 gene cotton fields and non-transgenic cotton fields. However, during peak abundances, indices of diversity and evenness of communities were at their lowest, while the reverse was true for index of dominance. Seasonal fluctuations were obvious with the insect community and pest sub-community, but that of natural enemy community varied more moderately across seasons. Overall therefore, RRM2 transgenic cotton did not significantly differ from non-transgenic cotton fields in insect community structure and composition and temporal dynamics of community characteristics, but the occurrence of insect pests in RRM2 transgenic cotton field might increase in years with suitable climate.

Gonionemus vertens is widely distributed throughout the Atlantic and Pacific Oceans and is one of venomous jellyfish species in China. To investigate the population genetic structure of G. vertens, we sequenced the mtDNA COI gene in 104 individuals collected from four geographic locations along the coast of the Yellow Sea and the Bohai Sea, and the homologous sequences of other 182 individuals which were obtained from GenBank were also analyzed. A total of 52 polymorphic nucleotide sites were detected among the 286 individuals, which defined 14 haplotypes. The overall haplotype diversity and nucleotide diversity were 0.743 ± 0.012 and 1.046% ± 0.097%, respectively. Compared with several other giant jellyfish species, the genetic diversity of G. vertens was at the higher level. AMOVA analysis indicated that extremely significant difference existed among the groups, within populations and among the populations within groups, with 60.17% molecular variation among the groups, 13.37% molecular variation within populations, and 26.46% molecular variation among the populations within groups. Pairwise fixation index (F_st) values showed that significant population structure existed between the G. vertens population collected in Xiamen waters with other populations collected from Laoting, Dongying, Yantai, and Dalian waters, and the population structure throughout Dalian with Dongying, or with Yantai were also significant. Phylogeographic analysis of the COI region revealed two lineages. The results indicated that the complex life cycle characteristics, dispersal ability, geographic isolation, together with the prevailing ocean currents in this region, may be important factors influencing the genetic structure of G. vertens.

To find out the main plant community types of uninhabited islands in the nearshore Xiamen, in mid-to-late October 2017, we recorded 360 vascular plant species, including 78 trees, 109 small trees or shrubs, 23 vines and 150 herbs. We also found 49 invasive alien species, 10 of which have been identified as the most serious invasive. Compositional analysis showed that vegetation in these 12 uninhabited islands were of tropical and sub-tropical types. Consistent with the subtropical geography of these islands, vegetation mainly consisted of pan-tropical species and its variants. Generally, the islands had similar species composition. Herbaceous plants dominated the flora of these islands. Power and logarithm functions best described the species-area relationships of island vascular plants. Area had the largest effect on species richness of these islands followed by other spatial parameters such as the ratio of shoreline length, elevation, and perimeter area. Habitat diversity and island edge affected similarity of vascular plant species among different islands. Except for Wuyu Isle, we did not find evidence for small island effects in these surveys.

Algae are important flora in mangrove ecosystems. Algae can be divided into three ecological groups, namely phytoplankton, benthic microalgae, and macroalgae in mangrove ecosystems, which play important roles in organic carbon production and nutrient cycle. Despite the importance of algae for ecosystem function, studies of mangrove ecosystems have focused on higher plants and animals, with few studies of algae. Due to their abundance in mangrove ecosystems, studies of algae can broaden our understanding about the structure and function of mangrove ecosystems. In this review, we first briefly introduce algal groups and their ecological importance in mangrove ecosystems. Then, we emphasize species composition and geographical distribution of phytoplankton, benthic diatoms and macroalgae, and their importance in key ecological processes such as primary production, water pollution, element cycle, and carbon stock dynamics in mangrove ecosystem. The researches have showed that the species number of phytoplankton and benthic diatoms in mangroves varied from dozens to hundreds, and diatoms are dominant both in species composition and abundance, which are important primary producer, animal food, and pollution indicator. Macroalgae are mainly composed of red algae, green algae, brown algae and blue-green algae. Green algae are dominant in species richness whereas red algae are abundant in quantity. Algae contribute significantly to the carbon pool by sequestering and cycling carbon. We propose that future studies should focus on algal diversity and its role in ecological processes in mangrove ecosystems. Furthermore, we suggest that studies of algae should be part of comprehensive investigations on long-term ecosystem dynamics. The influence of continental runoff and tidal patterns on algal diversity and blue carbon dynamics in mangrove areas also deserve more attention, on account of being directly related to nutrient replenishment and dynamics. Since algal diversity in mangrove sediment is influenced by physico-chemical and biological condition of the system, it could be used as an indicator of climate change and effects of anthropogenic activity on mangrove ecosystems.

The IUCN red list assessment lays the foundation for developing effective conservation strategies and action plan for biological species based on sound science. Since 2000, Chinese mycologists have assessed the threat status of macrofungi in China by using methods that incorporated but did not fully integrate IUCN categories and criteria. Because the number of species evaluated was limited and the geographical coverages were often relatively narrow, those assessments did not accurately reflect the overall status of Chinese macrofungi. To correct this gap, a nationwide Red List assessment of macrofungi was organized and the first national Red List of 9,302 species in 1,298 genera and 227 families was announced recently. More than 140 experts throughout the country took parts in the assessment. The results showed that 97 species of macrofungi were threatened. Based on the assessment results, combined with the current status of the conservation of macrofungi in China, five major measures were suggested to strengthen the conservation of these fungi: (1) Enforce the legislation of laws, speed up the establishment of regulations and improve the policy-making system; (2) Optimize the network system for in situ protection of macrofungi and enhance ex situ protection capability; (3) Further investigate the status of macrofungi and establish a monitoring program; (4) Strengthen outreach and education about mcrofungi in the popular science domain, i.e., raising public awareness of conservation of important fungal resources; (5) Increase funds for fungal conservation and to improve the supportive capability of science and technology.

With increasing international concern for biodiversity and human well-being, land degradation has increasingly become the foci of international conventions and processes. In the 2014-2018 Work Program of Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), “Land degradation and restoration” was included as one of the three major thematic assessment activities. The assessment report was completed by three hundred experts around the world in three years and adopted at the sixth plenary meeting of IPBES in March 2018. This article outlines the main contents and conclusions of the assessment, discusses possible impacts on other international processes, and proposes future work within our country. Based on the conceptual framework of IPBES, the assessment report comprehensively clarified the impact of land degradation on human life quality, the status and progress of land degradation, the role of direct and indirect drivers on land degradation, the relationship between land degradation and human well-being, and proposed suggestions for mitigating land degradation and promoting restoration. The assessment will provide policy makers in various countries with effective technical support for formulating policy tools and scientific references for negotiation of relevant international processes. As a country with rich biodiversity, China should accord importance to IPBES assessment mechanism and actively participate in strengthening the promotion of scientific achievements in the field of conserving biodiversity, initiate assessment on key domestic issues related to biodiversity and ecosystem services in a timely manner, to promote the construction of ecological civilization in our country, adopt a holistic approach to conserving our mountains, rivers, forests, farmlands, lakes, and grasslands, achieve the construction goal of beautiful China.

The 19th National Congress of the Communist Party of China put forward for the first time a new requirement that China should spearhead the construction of ecological civilization on global scale, of which biodiversity protection is an integral part. This paper systematically summarizes the major international experiences in promoting the Global Partnership for Business and Biodiversity (GPBB) advocated by the Convention on Biological Diversity, and gives policy proposals for China to promote the GPBB (or China Business and Biodiversity Partnership, CBBP). By analyzing GPBB practices in Germany, India, Canada, Peru, Australia, South Africa, Japan and South Korea, we find the main experience of these countries as follows: (1) the governments have important and varied roles, including management and providing funds or goods; (2) the patterns of organization are diverse, but usually they set up cross department decision-making bodies and secretarial offices; (3) membership generally requires signing agreements; some agreements focus on specific industries, some accord importance to institutional members; (4) the government generally provides legal and policy interpretation, knowledge and information dissemination, policy guidance and other services; (5) regarding funding, some mainly rely on the collection of membership dues while others rely on donations in kind or voluntary service, and some rely on PPP projects. We also draw the following conclusions: (1) a large number of enterprises are motivated and willing to participate in the Biodiversity Partnership Initiative; (2) the international resource network for promoting enterprise participation has been established; (3) limited by scale and capital, the participation of the vast enterprises requires more guidance and support of government. In 2015, China formally joined the GPBB. Although China has carried out several related activities to promote the GPBB, it still faces many challenges. First of all, the relevant documents have not been approved. Therefore, although many enterprises are willing to partner with China, there is a need to establish rules to follow. Secondly, China has not yet established a sound organizational mode and financial mechanism to promote GPBB. Finally, the 15th conference of the parties to the Convention on Biological Diversity (CBD) will be held in Beijing in 2020, which creates an urgent need to manage China’s partnership for business and biodiversity. In this regard, this paper suggests that the China Business and Biodiversity Partnership (CBBP) initiative should implement the two step strategy: (1) establish and launch the CBBP alliance initiative, and (2) increase the support of international conventions and state performance negotiations.