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Due to a dramatic increase in livestock, the impact of grazing on animal communities is a global conservation concern, especially in temperate forests. Recognizing the interaction between livestock and wildlife is essential for developing more effective and holistic strategies for wildlife conservation and sustainable livestock management. In this study, we conducted systematic camera trapping at 129 sites within the central portion of the Giant Panda National Park in China to assess the interspecific relationships between livestock and 21 sympatric wild species. Using the joint species distribution model, we fitted a null model and a constrained model to investigate the distinction between the spatial distribution relationship of species (as raw associations) and the interactions between livestock and wildlife (as residual associations). The results of raw associations showed that livestock exhibited a significant positive spatial co-occurrence with Temminck's tragopan, Himalayan porcupine, Chinese serow, Reeves's muntjac, and forest musk-deer (p 0.05), indicating no strong evidence of negative interactions between livestock and wildlife. Since livestock grazing is a source of income for residents, grazing management policies within the Giant Panda National Park should not prohibit all grazing practices.

Finger-jointed lumber production has now become the most extensively used method for spliced lumbers jointing together endwise. The properties of finger-jointed lumber are affected by many different factors such as the end- pressure. The main mechanical properties to be tested for structural use finger-jointed lumber include the modulus of elasticity in static bending and the bending strength. The most commonly used method for testing these properties at present is the experimental test. In this study, we used finite element method to investigate the end-pressure range, the modulus of elasticity in static bending and the bending strength for Pinus sylvistriv var. finger-jointed lumber under three different fitness ratios (0 mm, 0.1 mm, 0.3 mm). With finite element analysis (FEA) modelling results compared with the experimental test results, it is possible to find the relationship between these two kinds of results and use the FEA to predict the properties of finger-jointed lumber. The FEA applied in the end pressure tests showed a narrower range compared with the modelling results. It indicated that the FEA could be used in the prediction of the end pressure for finger-jointed lumber. The modelling results for modulus of elasticity (MOE) test and bending strength (MOR) test showed about 20% discrepancies compared with the experimental results. Moreover, the MOE modelling results showed the same trend as experimental results under three different fitness levels while the MOR modelling results showed the different trend. It can be concluded that the FEA is a feasible way in analysing the properties of finger-jointed lumber if the errors could be eliminated properly. Some modifications should be made in order to realize the prediction of the properties of finger-jointed lumber more accurately.

With the increasing emphasis on sustainable development, bamboo is receiving an increasing attention as a kind of forest resource. But bamboo is readily discoloured by mould fungi, which greatly limits the applications of bamboo. In this research, ZnO nanoparticles were successfully fabricated on the surface of bamboo timber by a simple low-temperature wet chemical method. The morphology, chemical structure, and crystalline structure of the samples were characterized by using scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS). XRD studies confirmed that the as-prepared ZnO nanoparticles were wurtzite. The microstructure and hydroxyl groups in the bamboo timber surface at the wet state provided cavities and affinity for the creation and the immobilization of ZnO nanoparticles on the bamboo timber surface through electrostatic and hydrogen bonding interactions. Moreover, the mould-resistance of ZnO coated bamboo timber was also in focus on the present study. The results indicated that bamboo timber treated with ZnO had a better resistance against Aspergillus niger V. Tiegh (A. niger) and Penicillium citrinum Thom (P. citrinum), but poor against Trichoderma viride Pers. ex Fr (T. viride). Keywords: Bamboo timber, ZnO nanoparticles, Wet chemical method, Surface, Mould-resistance

Bermudagrass (Cynodon dactylon) is a widely used warm-season turfgrass and one of the most drought tolerant species. Dissecting the natural variation in drought tolerance and physiological responses will bring us powerful basis and novel insight for plant breeding. In the present study, we evaluated the natural variation of drought tolerance among nine bermudagrass varieties by measuring physiological responses after drought stress treatment through withholding water. Three groups differing in drought tolerance were identified, including two tolerant, five moderately tolerant and two susceptible varieties. Under drought stress condition, drought sensitive variety (Yukon) showed relative higher water loss, more severe cell membrane damage (EL), and more accumulation of hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), while drought tolerant variety (Tifgreen) exhibited significantly higher antioxidant enzymes activities. Further results indicated that drought induced cell injury in different varieties (Yukon, SR9554 and Tifgreen) exhibited liner correlation with leaf water content (LWC), H₂O₂ content, MDA content and antioxidant enzyme activities. Additionally, Tifgreen plants had significantly higher levels of osmolytes (proline level and soluble sugars) when compared with Yukon and SR9554 under drought stress condition. Taken together, our results indicated that natural variation of drought stress tolerance in bermudagrass varieties might be largely related to the induced changes of water status, osmolyte accumulation and antioxidant defense system.