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The cao vit gibbon Nomascus nasutus, also known as eastern black crested gibbon, is categorized as Critically Endangered on the IUCN Red List and was considered one of the world's 25 most threatened primates. The only known population occurs along the border between China and Viet Nam. Accurate information on population size and dynamics is critical for the species’ conservation, but population surveys conducted in only one country may over- or underestimate total population size because the home ranges of cao vit gibbon groups often cross the international border. In 2007 and 2016 we conducted two collaborative transboundary censuses of the cao vit gibbon populations in the Trung Khanh Cao Vit Gibbon Species and Habitat Conservation Area in Viet Nam and the Bangliang Gibbon National Nature Reserve in China. The results showed a population size of 102–110 in 2007, which increased to 107–136 in 2016. Our results indicate that previous surveys conducted separately in Viet Nam and China underestimated the global population size of this species. According to our more comprehensive surveys, the gibbon population is increasing slowly. The gibbons and their habitat are legally protected in both countries. Hunting and charcoal making have not been reported in this area since 2007. As habitat carrying capacity is a limiting factor, habitat restoration is required. However, lack of funding to protect the cao vit gibbon remains a challenge.

Camellia oleifera Abel. is an important economic tree species of southern China. In this study, we evaluated the mating system and genetic diversity of a series of cultivars of C. oleifera ‘Ruan Zhi’. A total of 159 individuals from the progenies of four cultivars were tested by simple sequence repeat molecular markers. Results reveal that 11 pairs of primers showed polymorphism and their polymorphism information content value was greater than 0.73, suggesting that these primers could be used to identify the genetic diversity of open-pollinated populations. The average number of effective alleles (Ne = 4.88) was significantly different from the average number of alleles (Na = 12.18), and their distribution in the sample population was not uniform. The average observed heterozygosity (Ho = 0.96) was greater than the average expected heterozygosity (He = 0.79), and the population heterozygote was excessive. Shannon index was 1.84 and populations showed high genetic diversity. As regards to the mating system, the multilocus outcrossing rate was 0.996, and the single locus 0.866. These results indicate a high degree of outcrossing by C. oleifera ‘Ruan Zhi’. We recommend selecting individuals for high genetic gain from the progenies of cultivars because of outcrossing characteristics and genetic diversity for application to germplasm conservation and promotion.

The morphological and anatomical traits of needles are important to evaluate geographic variation and population dynamics of conifer species. Variations of morphological and anatomical needle traits in coniferous species are considered to be the consequence of genetic evolution, and be used in geographic variation and ecological studies, etc. Pinus tabuliformis is a particular native coniferous species in northern and central China. For understanding its adaptive evolution in needle traits, the needle samplings of 10 geographic populations were collected from a 30yr provenience common garden trail that might eliminate site environment effect and show genetic variation among populations and 20 needle morphological and anatomical traits were involved. The results showed that variations among and within populations were significantly different over all the measured traits and the variance components within population were generally higher than that among populations in the most measured needle traits. Population heritabilities in all measured traits were higher than 0.7 in common garden sampling among populations. Needle traits were more significantly correlated with longitude than other factors. First five principal components accounted for 81.6% of the variation with eigenvalues greater than 1; the differences among populations were mainly dependent on needle width, stomatal density, section areas of vascular bundle, total resin canals, and mesophyll, as well as area ratio traits. Ten populations were divided into two categories by Euclidean distance. Variations in needle traits among the populations have shown systematic microevolution in terms of geographic impact on P. tabuliformis. This study would provide empirical data to characterize adaptation and genetic variation of P. tabuliformis, which should be more available for ecological studies.