Cordana sinensis sp. nov. from southern China

A new species, Cordana sinensis, is described and illustrated from a specimen collected on dead branches of an unidentified broadleaf tree in Jiangxi Province, China. It is characterized by its integrated, polyblastic conidiogenous cells that produce ovoid to obclavate, medially 1–2-septate pale brown, smooth conidia with a slightly prominent hilum. A dichotomous key and a synoptic table to Cordana species, are provided.

Cladorrhinum yunnanense sp. nov. from China

A new asexual fungus, Cladorrhinum yunnanense, isolated from unidentified fallen leaves of a broadleaf tree in Yunnan, China, is described by morphological characters and phylogenetic analyses of DNA sequence data from three loci (ITS, LSU and TUB).

The Introduction of Broad-Leaved Tree Species Drives The Process of Nutrient Cycling in Forest Soil

Background Pure cypress forests experience problems such as reductions in biodiversity, lowered capabilities for water and soil conservation, decreased underground productivity and land degradation. To improve the conditions of pure forests, we studied the effects of mixed gaps on the cypress (Cupressus funebris) pure forest, selecting the Chinese toon (Toona sinensis), which is a deciduous broad-leaved tree, as the mixed tree species. We examined the variations in the concentrations of C, N, and P and their ratios in plant tissues, litter and soils in different seasons in pure cypress forests with 4 different sizes of mixed gaps (50, 100, 150, 200 m2). Results The leaf N:P ratios of cypress and Chinese toon were 10.77 and 12.74, respectively, and N was the main limiting factor for tree growth in the study area. The N and P resorption rates of the cypress pure forest were 57.4% and 60.7%, respectively, and mixed gaps with Chinese toon increased the resorption rates. An analysis of correlations among leaf-litter-soil stoichiometry indicated that the correlations between the soil nutrient elements and the corresponding plant leaves and litter increased when the broadleaf tree species was introduced into the cypress pure forest. Conclusions These results indicate that the introduction of broad-leaved species was favorable for triggering the forest soil nutrient recycling process.

Genetic Diversity and Structure of Latvian Tilia cordata Populations

Changing climatic conditions are transforming the ecological and silvicultural roles of broadleaf tree species in northern Europe. Small-leaved lime (Tilia cordata Mill.) is distributed throughout most of Europe, and is a common broadleaf species in Latvia. This species can tolerate a broad range of environmental and ecological conditions, including temperature, water availability, and soil types. The aim of this study was to assess the genetic diversity and differentiation of Latvian T. cordata populations using nuclear microsatellite markers developed for Tilia platyphyllos. After testing of 15 microsatellite markers, Latvian T. cordata samples were genotyped at 14 micro-satellite loci. Latvian T. cordata populations had high genetic diversity, and were not overly isolated from each other, with moderate gene flow between populations. No highly differentiated populations were identified. Vegetative reproduction was identified in most analysed populations, and almost one-third of analysed individuals are of clonal origin. T. cordata has high timber production potential under the current climatic and growth conditions in Latvia, and therefore this species has potential for use in forestry, as well as playing a significant role in maintaining biodiversity and other ecosystem services.

Pronounced loss of Amazon rainforest resilience since the early 2000s

The resilience of the Amazon rainforest to climate and land-use change is of critical importance for biodiversity, regional climate, and the global carbon cycle. Some models project future climate-driven Amazon rainforest dieback and transition to savanna1. Deforestation and climate change, via increasing dry-season length2,3 and drought frequency – with three 1-in-100-year droughts since 20054-6 – may already have pushed the Amazon close to a critical threshold of rainforest dieback7,8. However, others argue that CO2 fertilization should make the forest more resilient9,10. Here we quantify Amazon resilience by applying established indicators11 to remotely-sensed vegetation data with focus on vegetation optical depth (1991-2016), which correlates well with broadleaf tree coverage. We find that the Amazon rainforest has been losing resilience since 2003, consistent with the approach to a critical transition. Resilience is being lost faster in regions with less rainfall, and in parts of the rainforest that are closer to human activity. Given observed increases in dry-season length2,3 and drought frequency4-6, and expanding areas of land use change, loss of resilience is likely to continue. We provide direct empirical evidence that the Amazon rainforest is losing stability, risking dieback with profound implications for biodiversity, carbon storage and climate change at a global scale.

Camposporium chinense sp. nov. from Jiangxi, China

A new species, Camposporium chinense, is described and illustrated from a specimen collected on dead branches of an unidentified broadleaf tree in Jiangxi, China. The fungus is characterized by its fusiform, 9–12-septate, versicolored conidia with an unbranched, aseptate apical appendage. A key to Camposporium species is provided.