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The pipe model theory has been applied to estimate allometry of trees in many regions; however, its reliability and generality need more verification for estimating crown biomass in China. In the present study, the crown biomass of Larix olgensis plantations in four sites in northeast China was estimated using the pipe model, and the correlation efficiency index of larch crown biomass for pipe model estimation was 0.953. The crown biomass of larch plantations could be accurately estimated by the tree height, crown base height, and stem area at breast height. Meanwhile, the effects of site, stand density, and age on the accuracy of crown biomass estimated by the pipe model were detected. The covariance analysis showed that the effect of age on crown biomass was 0.024, indicating that age had a significant effect on the estimation accuracy in this model, while site and stand density had no significant effects (p = 0.180 and p = 0.169). Our study showed that the crown biomass of L. olgensis plantations in northeast China could be accurately estimated using the pipe model, and we recommend considering the age effect in practical applications. [ABSTRACT FROM AUTHOR]

Typical water–energy dynamics hypothesis assumes that the effects of water and energy on species richness vary geographically, and there is a latitudinal shift from water dominated to energy dominated. However, the effects of available water and energy on species richness patterns might be influenced by local climate change. In this study, geographically weighted regression was used to quantitatively analyze the relationship between pteridophyte species richness and water as well as energy. The effect of local climate conditions on richness was estimated by establishing the energy and water model. The results showed that the relationship between Chinese pteridophyte richness and water was stronger than that with energy across the country. There was no latitudinal transition line from water dominance to energy dominance in China. Furthermore, the sensitivity of pteridophyte richness to the changes in ambient climatic factors increased with the decrease in water and energy availability. Overall, pteridophyte richness is more dependent on available water than energy, and the decrease of water and energy availability is crucial for limiting pteridophyte richness. As global climate change intensifies, the threat to pteridophyte richness in cold and arid regions will become more severe, and more attention should be given to the monitoring and conservation of species diversity in these regions. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) are widely utilized and can accumulate in lacustrine ecosystems, posing significant ecological and human health hazards. Most studies on PAEs focus on individual lakes, lacking a comprehensive and systematic perspective. In response, we have focused our investigation on characteristic lakes situated along the Eastern Route of the South-to-north Water Diversion Project (SNWDP-ER) in China. We have detected 16 PAE compounds in the impounded lakes of the SNWDP-ER by collecting surface water samples using solid-phase extraction followed by gas chromatography analysis. The concentration of PAEs were found to between 0.80 to 12.92 μg L−1. Among them, Bis (2-ethylhexyl) phthalate (DEHP) was the most prevalent, with mean concentration of 1.56 ± 0.62 μg L−1 (48.44%), followed by Diisobutyl phthalate (DIBP), 0.64 ± 1.40 μg L−1 (19.87%). Spatial distribution showed an increasing trend in the direction of water flow. Retention of DEHP and DIBP has led to increased environmental risks. DEHP, Dimethyl phthalate (DMP) etc. determined by agriculture and human activities. Additionally, Dibutyl phthalate (DBP) and DIBP mainly related to the use of agricultural products. To mitigate the PAEs risk, focusing on integrated management of the lakes, along with the implementation of stringent regulations to control the use of plasticizes in products. [Display omitted] • Concentrations of PAEs increase in the direction of water flow. • DEHP and DIBP predominant in the impounded lakes of SNWDP-ER. • PAEs retention is a potential hazard to the water quality and security. • SNWDP-ER's top hazards: DEHP, DIBP, BBP, DBP • PAEs in SNWDP-ER primarily from human activities and agricultural production. [ABSTRACT FROM AUTHOR]

1. Predator–prey interactions, especially those involving herbivorous insects, are of great importance in maintaining biodiversity. Predation pressure varies temporally in response to prey availability and activity. However, little is known about the patterns and drivers of fluctuations in predation pressure at fine temporal scales. 2. Artificial caterpillars (placed on plant leaves at breast height) were used to assess changes in predation pressure across four time intervals of the day in a monsoonal tropical rainforest in south‐west China. The study examined how assemblage composition of arboreal ants, the dominant predators, changed across the same time intervals. The potential linkages between biotic (arboreal ants) and abiotic (temperature and light intensity) factors with predation rate were evaluated. 3. Predation rate on caterpillars during the early part of the night (19.00–01.00 hours) was significantly higher than in the morning, afternoon, or late night. Ant assemblage composition, rather than species richness or total abundance, best explained the variations in predation rate on artificial caterpillars. 4. The results help to strengthen understanding of trophic interactions by demonstrating that predation pressure fluctuates at finer timescales than previously tested, and that a particular set of ant species may play major roles in predation on caterpillars and possibly other organisms. [ABSTRACT FROM AUTHOR]

Background: Rice cultivation under film mulching with no flooding is widely used as an effective water-saving technology. Different colors of film mulch have different effects on the soil hydrothermal environment and crop growth because of their different optical properties. However, the effects of different colors of film mulch on soil temperature and rice physiological growth are not clearly understood., Results: Field experiments were conducted in 2019 and 2020 to investigate the effects of different color mulches on soil temperature and rice growth in a non-flooded condition. Transparent film (TM), black film (BM), two-color film (BWM, silver on the front and black on the back), and no film (NM) in a non-flooded condition were designed. Soil temperature variation at different soil depths of 0-0.25 m and rice plant height, stem thickness, dry matter, yield and quality were monitored. The results showed that compared to no mulching, the mulching treatment effectively increased the average soil temperature during the whole rice growth stage with the soil temperature ranked TM > BM > BWM. Compared with NM, the BM and BWM treatments increased rice yield by 12.1-17.7% and 6.4-14.4% in 2019 and 2020, respectively. The BWM had 18.2% and 6.8% greater gel consistency than NM in 2019 and 2020, respectively., Conclusion: Transparent film should be applied with care because of the high soil temperature stress. Black film and two-color film (silver on the front and black on the back) could be better option for rice yield, increasing and quality improving in a non-flooded condition. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)