关键词： 野生动物监测   物种分类   零样本分类   层次化分类  

摘要： 针对野生动物监测图像物种分类模型结果复核成本高昂的问题,本文提出一种基于物种分类树的层次化分类方法。该方法在物种分类树的纲、目、科、属和种5个分类层级上进行零样本分类,通过提供更丰富的物种判定信息,降低复核模型结果的人工成本;利用类别间的层次关系,引入软决策和路径矫正策略,在细粒度类别上分类错误时,模型提供的粗粒度结果也具有参考价值。与路径矫正策略增强的基线方法相比,该方法在5个分类层级上的准确率分别提升了0.27%、1.44%、1.42%、1.39%和1.03%,并将错误严重程度降低了1.1%。本文提出的方法提高了层次化分类的准确率和一致性,增强了模型输出结果的可解释性,降低了人工复核成本,有利于提高生态学家对深度学习模型的信赖程度和使用意愿。

摘要： 温带森林的树上世界虽然单调，却仍然称得上是一座立体的生态城堡。长白山森林中，有飞鼠、松鼠、啄木鸟这样的树上居民，也不乏松茸、猴头菇、香菇这样的人间珍馐。森林中的树木为自己而生，也为万物而生。深入树的世界，便了解了生命之间不动声色却又深切的依存与合作。

摘要： 编辑手记：作品对刚开始枯萎的叶子、靠近根部很绿的叶子、大面积枯萎而掉落的叶子，进行了对比呈现。重点呈现的3片树叶，颜色的选用非常讲究，比较直观。作品日期为10月底，整棵树中叶片绿色、黄色大致比例有所再现，这也是观察细致入微的表现。只要我们细心观察一棵树，很容易看到不同生长阶段的叶子，如芽苞、嫩芽、刚舒展开的新叶、表面已经有许多落尘的叶片、颜色开始变化的老叶、已经枯萎即将掉落（已经掉落）的死叶、腐烂转化的死叶等。所以，即便是我们只聚焦叶子，也可能会发现更多。关注并呈现出这些细节，就能了解生命的过程，意识到新陈代谢。

关键词： 树鼩   自身免疫性疾病   动物模型  

摘要： 建立动物模型是研究人类疾病发病机制及诊疗手段的重要途径。目前多采用啮齿类动物疾病模型,但其与人类遗传学基础相差甚远,不能复制人类疾病的组织学、免疫学特点的全貌。灵长类动物疾病模型更为接近于人的发病特征,但其实际应用中面临多种困难。树鼩具有独特的遗传学特性,是潜在的理想试验动物模型。树鼩已成功建立多种疾病的动物模型,但在自身免疫性疾病中少见应用。本文综述树鼩的基因、免疫分子、免疫器官等研究进展,探讨树鼩用于建立自身免疫疾病动物模型的优势及前景。

关键词： 北树鼩滇西亚种   生理常值   实验动物  

摘要： 树鼩在2000年国家林业局将其列为《国家保护的、有益的或者有重要经济、科学研究价值的陆生野生动物名录》中,并于最近几年在医学上广泛应用的实验动物之一。已证实树鼩具有与人高度相似脑神经和视觉神经,同时,是有文献记载除了黑猩猩之外唯一一种动物能感染上人的乙型肝炎病毒的动物。本文宗旨是为建立人工饲养树鼩的生理正常值范围,用于筛选合格实验动物,为诊断树鼩疾病及应用研究提供基础资料。实验对象为人工饲养繁育30只成年北树鼩滇西亚种(雄性树鼩21只,雌性鼩9只),通过生理常值指标测定初步建立了北树鼩滇西亚种生理常值指标参数;北树鼩滇西亚种的不同性别的对比常值参数;北树鼩滇西亚种血液部分生理常值与恒河猴、大白鼠、人参考值对比。结果显示,不同性别北树鼩滇西亚种生理常值指标值,发现呼吸、血沉(24小时)、血红蛋白、嗜中性分叶核白细胞、差异性显著(P<0.05),白细胞计数差异极显著(P<0.01),其余11项指标值均无统计学差异。树鼩生理指标的检测结果某些数值显示与恒河猴、大白鼠、人有一定的差异(如体温、呼吸、心率高于恒河猴、大鼠、人参考值)。

关键词： 热带丛林   娜娜   马来西亚   酒量   动物   注意力  

摘要： 塔塔和娜娜在草地上烤肉串,香极了。“来,干一杯。”娜娜豪爽地举起手中杯。“这……”塔塔为难地看着手中的酒杯。作为一个男生、一个哥哥,他的酒量比不上妹妹,说出来有点丢人啊。塔塔眼珠一转,想了个主意分散娜娜的注意力:“你哥酒量再好,也很难做到天天豪饮而不醉。然而,生长于马来西亚热带丛林中的笔尾树朐每天以‘酒’为食,仍能清醒如初,是世界上酒量最好的动物。”

关键词： Sub-Saharan Africa   Grassland management   Soil respiration   Soil temperature   Soil water content  

摘要： Although grazing is the primary land use in the savanna lowland of southern Kenya, the effects of grazing on soil carbon dioxide flux (RS) remain unclear. A 12-month study was conducted from January to December 2020 on the effects of six grazing intensities sites (overgrazed (OG), heavily grazed (HG), moderately grazed (MG), moderately to lightly grazed (M-LG), lightly grazed (LG) and no grazing (NG)) on RS on. A camera trap was used to monitor the total number of animals at each site, indicating the grazing intensity. Weekly measurements of RS were taken using static greenhouse gas chambers along with simultaneous measurements of soil temperature (TS) and volumetric soil water content (WS) (depth of 5 cm). Mean RS at HG, MG, M-LG and LG sites was approximately 15-25% higher than at NG and OG sites (p < 0.001). Mean WS increased with decrease in grazing especially in the dry season, while TS increased with increase in grazing. We observed bimodal temporal variation in RS and WS due to two wet seasons in the year. Thus, variation in RS across the study period followed the changes in WS rather than those in TS. Mean values of RS in the wet seasons were significantly higher (> 45%) than those in the dry seasons, and WS accounted for 71% of the temporal variability in RS (p < 0.05). In addition, the enhanced vegetation index (EVI, interpreted as a proxy for vegetation cover) explained 60% of the variance of RS, and WS and EVI together explained 75%. EVI showed a negative relationship (p < 0.05) with animal intensity, indicating that more grazing reduced vegetation cover and, consequently, soil organic carbon and biomass. Soil bulk density was lower at less grazed sites. While RS variability was unaffected by total nitrogen content, pH, and texture, correspondence analysis demonstrated that the main factors influencing RS dynamics across the year under different grazing intensities were WS and vegetation cover. Our results contribute to closing the existing knowledge gap

关键词： 智慧树平台   动物生理学实验教学   改革  

摘要： 笔者介绍了塔里木大学动物生理学实验在传统教学中出现的一些问题,提出了利用智慧树建立翻转课堂,应用于动物生理学实验教学的改革策略,通过转变教学模式,丰富课程的授课形式,合理设置评估方法等措施,使优质教学资源得到合理分配,充分发挥了学生的主观能动性,培养了其独立思考和解决问题的能力,提升了课程的学习效果。

关键词： Associational resistance   Herbivory   Meta-analysis   Natural enemies   Top-down control   Tree diversity   Pest control  

摘要： The natural enemies hypothesis predicts that the abundance and diversity of antagonists such as predators and parasitoids of herbivores increases with the diversity of plants, which can lead to more effective top-down control of insect herbivores. However, although the hypothesis has received large support in agricultural systems, fewer studies have been conducted in forest ecosystems and a comprehensive synthesis of previous research is still lacking. We conducted a meta-analysis of 65 publications comparing the diversity, abundance or activity of various groups of natural enemies (including birds, bats, spiders and insect parasitoids) in pure vs. mixed forest stands. We tested the effects of forest biome, natural enemy taxon and type of study (managed vs experimental forest). We found a significant positive effect of forest tree diversity on natural enemy abundance and diversity but not on their activity. The effect of tree diversity on natural enemies was stronger towards lower latitudes but was not contingent on the natural enemy taxon level. Overall, our study contributes toward a better understanding of the "natural enemies hypothesis" in forest systems and provides new insights about the mechanisms involved. Furthermore, we outline potential avenues for strengthening forest resistance to the growing threat of herbivorous insects. (C) 2021 Published by Elsevier GmbH on behalf of Gesellschaft far Okologie.

关键词： Burned forests   Cattle ranching   Forest dynamics   Berberis microphylla   Nothofagus antarctica  

摘要： Spiny shrubs can generate positive interactions with palatable trees in sites affected by abiotic and biotic stress (e.g. fire, and consumption by herbivores). The objective of this study was to assess the role of native shrubs (Berberis microphylla) in mitigating large herbivore browsing on tree saplings (Nothofagus antarctica) in degraded (burnt) forests of the central area of Tierra del Fuego, Argentina. For that, we assessed, in 16 forest sites, the browsing intensity and the browsing height in N. antarctica saplings that were alone (n = 10 per site), and in saplings that were spatially associated with B. microphylla shrubs (n = 10 per site). The tree and shrub height were also measured. The results indicated that browsing damage on hire trees occurred at a higher height and with lower intensity in the tree-shrub association than in trees that were alone. Furthermore, the browsing height was positively related with the shrub height and with the tree height. The shorter trees with greater shrub cover were more protected. Our results indicate that the presence of spiny shrubs decreases the damage caused by browsing, and protects trees during the early regeneration stage. However, the structural characteristics of shrubs are determinant of the protecting effect in these Patagonian forests. This tree-shrub interaction is highly relevant in the dynamics of degraded forests to ensure the system continuity in ecological and productivity terms.