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Abstract Background Being a promising tropical woody oilseed crop, the evergreen and recurrent plants of Sacha Inchi ( Plukenetia volubilis L.) has complex phenology and source–sink interactions. Carbon source–sink manipulations with control and two treatments (reduce source, ca. 10% mature leaf pruning; reduce sink, 10% fruitlet thinning) were conducted on 2.5-year-old field-grown P. volubilis plantation during the early-wet season in a seasonal tropical area. Results Leaf photosynthetic rate and specific leaf area largely remained unchanged in response to defoliation or defloration. Compared with control, higher N contents on average were observed in both remaining leaves and branches of the defoliated plants, suggesting that N-mobilization was mainly due to the enhanced N uptake from soil. Carbon, but not N, is a source-driven growth process of P. volubilis plants, as defoliation reduced the contents of non-structural carbohydrates (especially sugar) in branches, although temporally, whereas defloration increased available C reserve. The seasonal dynamic pattern of fruit ripening was altered by source–sink regulations. Total seed yield throughout the growing season, which depends on fruit set and retention (i.e., number of matured fruit) rather than individual fruit development (size), was slightly increased by defloration but was significantly decreased by defoliation. Compared with control, defloration did not enrich the KEGG pathway, but defoliation downregulated the TCA cycle and carbohydrate and lipid metabolisms in fruitlets after 24 days of the applications of source–sink manipulation. Conclusion Carbohydrate reserves serve to buffer sink–source imbalances that may result from temporary adjustment in demand for assimilates (e.g., defloration) or shortfalls in carbon assimilation (e.g., defoliation). Defoliation is disadvantageous for the yield and also for carbohydrate and lipid accumulation in fruits of P. volubilis plants. Although more studies are needed, these results provide new insights to the further improvement in seed yield of the strong source-limited P. volubilis plants by source/sink manipulations.

A novel branch-trunk Ag hierarchical nanostructure was synthesized via a galvanic replacement reaction combined with microwave-assisted synthesis using Te nanowire as a sacrificial template. The Te nanowire was synthesized via a hydrothermal process. We further investigated the potential application of the obtained hierarchical nanostructures in electrochemical sensor analysis. The results showed that the as-prepared sensor exhibited a wide linear range with 0.05 µM to 1.925 mM (R = 0.998) and the detection limit was estimated to be 0.013 µM (S/N = 3). These results indicate the branch-truck Ag hierarchical nanostructures are an excellent candidate material for sensing applications.

The impact of climate warming on wetland ecosystems is a current focal point in ecological research. In this study, the Napahai wetland, a typical plateau wetland in northwest Yunnan Province, was selected as the study site to understand the growth and survival strategies of emergent plants in a plateau wetland under climate warming conditions. Open-top chambers (OTCs) were used to simulate warming in three treatments (i.e., control group, 2.0 ± 0.5°C, and 4.0 ± 0.5°C) in order to study the responses of the functional traits of the dominant emergent plant Schoenoplectus tabernaemontani to simulated warming. The results showed that simulated warming significantly reduced the photosynthetic carbon assimilation capacity and biomass accumulation of S. tabernaemontani, as well as its nitrogen content and vascular bundle density, while it significantly increased the vascular bundle size. The growing season accumulated temperature (AT) and the mean temperature of the hottest month (WT) were the main temperature factors influencing the functional traits of S. tabernaemontani. In summary, simulated warming significantly affected the functional traits of S. tabernaemontani, which demonstrated effective adaptation to warming conditions. As the temperature rises and the light and productivity decrease, S. tabernaemontani prioritizes the supply of limited resources to the underground part to ensure the biomass supply of the reproductive structure. This study provides a case for revealing the response patterns and ecological adaptation strategies of plateau wetland plants to climate warming. [ABSTRACT FROM AUTHOR]

A novel branch-trunk Ag hierarchical nanostructure was synthesized via a galvanic replacement reaction combined with microwave-assisted synthesis using Te nanowire as a sacrificial template. The Te nanowire was synthesized via a hydrothermal process. We further investigated the potential application of the obtained hierarchical nanostructures in electrochemical sensor analysis. The results showed that the as-prepared sensor exhibited a wide linear range with 0.05 μM to 1.925 mM (R = 0.998) and the detection limit was estimated to be 0.013 μM (S/N = 3). These results indicate the branch-truck Ag hierarchical nanostructures are an excellent candidate material for sensing applications. [ABSTRACT FROM AUTHOR]

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• O Understory vegetation recovery generally occurs faster than soil recovery in coastal forest. • O Soil microbes form spatially separated groups induced by reforestation. • O No consistent pattern exists for plant or soil traits responded to afforestation. • O Recovery of understory plant and soil traits strongly depends on soil conditions. The low-cost, ecologically friendly afforestation in coastal regions has been used to mitigate the natural degraded ecosystem. However, ecological consequences of this land use change are poorly known. We investigated the a short-term (2.5 years) effect of afforestation of a pioneer tree species, Casuarina equisetifolia , on understory vascular plants and surface soil traits (0–10 cm) at two closely-located sites (Heipaijiao and Haigui) in a subtropical coastal region, south China. Generally, plant abundance, vegetation coverage, and soil fertility in the natural degraded land were higher in Heipaijiao than in Haigui. After afforestation, the understory vascular plant abundance (increased by 46.1 %) and coverage (increased by 86.1 %) in Heipaijiao were recovered remarkably faster than those in Haigui; but there was slow recover in plant species composition, especially in Haigui. Owing to afforestation, soil water content and organic C (especially particulate organic C), electricity conductivity, Na+ and available K, and soil microbial biomass C increased but pH value decreased; the contents of total N, P and K, available N and P contents, and mineral-associated organic C had no great difference. Afforestation enhanced the richness, rather than alpha diversity, of soil bacteria and fungi. Soil microbes formed four spatially separated groups exhibiting overlapping and distinct microbial communities across different land-use types. Afforestation had a significant effect on the putative two-dominant functions of soil bacteria, i.e., soil C and N cycling. Thus, afforestation can maintain ecosystem multifunction quantified based on C sequestration, nutrient cycling and plant productivity. Understory plant recovery occurred faster than soil recovery; but no consistent restoration pattern existed for soil traits responded to afforestation. Recovery of understory plant and soil traits strongly depends on local soil conditions. This afforestation success story of selecting a well-adapted pioneer tree (C. equisetifolia) as foundation species provides insights into the restoration practice under harsh environmental conditions. [ABSTRACT FROM AUTHOR]