Results 21 to 30 of about 2,494 (164)

Flexible parental care in a songbird correlates with sex‐specific responses to seasonal phenology, mating opportunity and reproductive success

open access: yesJournal of Animal Ecology, EarlyView.
This population‐comparative study reveals that male and female parents respond differently to social and ecological conditions. This sex‐specific responsive strategy is related to the incongruent parental care systems across populations in Chinese penduline tits.
Jia Zheng   +5 more
wiley   +1 more source

晋西人工防护林乡土树种抗旱性研究

open access: yesShuitu Baochi Xuebao, 2000
应用压力室技术对晋西北7个乡土造林树种的水分参数进行了研究,分析了各树种的抗旱性及其季节变化规律。结果表明:(1)各树种抗旱性具有一定的季节变化格局,根据本地区气候变化特征,其基本规律是:生长季初期最弱,炎热干旱的季节有所增强,降水峰期再次减弱,而到生长季末期则是一年中抗旱性最强的时期。(2)应用抗旱性综合指标判定7个树种抗旱性强弱,其顺序依次为:山杏,海红,榆树,刺槐、沙刺,红柳,沙枣。(3 ...
柴宝峰 王孟本
doaj   +2 more sources

Seasonal variation and implications of the concentration of different phosphorus species and phosphate oxygen isotope composition in Jiulong River estuary [PDF]

open access: yes, 2015
磷是生物生长所必须的营养元素,在天然水体环境中,磷的浓度比较低,可能会限制生物的生长。而若环境中的磷浓度过高,就会造成富营养化,甚至引发赤潮。磷在自然界中一般以磷酸盐的形式存在,主要分为溶解态磷和颗粒态磷,溶解态磷分为溶解无机磷和溶解有机磷,颗粒态磷又分为颗粒无机磷和颗粒有机磷。 磷是一种颗粒活性元素,它只有一种稳定同位素(31P),因此无法利用稳定同位素技术研究磷循环。研究发现磷酸盐氧同位素在生物或酶的作用下会与水发生氧交换,而非生物作用磷酸盐和水间不会发生氧交换。因此一些研究用磷酸盐氧同位素 ...
王娟
core  

Prioritizing bat roosts for conservation with a global multicriteria bat roost priority index based on community science

open access: yesConservation Biology, EarlyView.
Abstract Prioritization in conservation is crucial for the development of efficient and effective decision‐making policies. For many decades, the importance of some species and their habitats has been assessed and applied in conservation legislation, but bats and their diurnal roosts have ofbeen overlooked.
David López‐Bosch   +6 more
wiley   +1 more source

光周期对雄性哺乳动物季节性精子发生的影响及其调控机制

open access: yes野生动物学报, 2022
季节性繁殖是哺乳动物在长期的进化过程中,为了应对外界环境的变化,选择合适的季节进行繁殖的行为。雄性哺乳动物在非繁殖季节表现为睾丸退化,精子发生的减数分裂过程受阻,进入繁殖季节性腺恢复,重新启动精原细胞的分裂和分化,这种季节性精原细胞分裂和分化与精子发生受到环境因子和多种体内激素的调节。就光周期信号分子——褪黑激素通过TSH-DIO2/DIO3-T3逆行通路和HPG轴—睾酮—视黄酸信号系统对雄性哺乳动物繁殖季节性调控的研究综述可知:褪黑激素通过调控HPG轴的功能促进精子的发生 ...
杨 笛, 陈婉依, 宫泽儒, 杨 明
doaj  

Seasonal and intra-seasonal dynamics of sea surface pCO2 on the mid-shelf of the East China Sea: buoy-based time series observations [PDF]

open access: yes, 2015
近岸水体在全球海洋碳循环中扮演重要角色,但由于其地处海陆交界以及受人为活动的扰动,近岸水体的碳循环过程复杂且多变,这种复杂的变化过程也反映在海水二氧化碳分压(pCO2)随时间的剧烈波动上。鉴于近岸水体海表pCO2的时间变异性,特别需要长期高频的时间序列观测,以甄别其在不同时间尺度的变化规律和调控机制,并且为一些难以通过船载观测捕捉到的短期剧烈变化事件(如台风)提供研究的机会。 本研究主要基于浮标观测,该浮标观测点位于东海中部陆架(124.5°E31°N),水深约60m ...
吴瀛旭
core  

Internal physiological drivers of leaf development in trees: Understanding the relationship between non‐structural carbohydrates and leaf phenology

open access: yesFunctional Ecology, Volume 40, Issue 5, Page 1151-1164, May 2026.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Plant phenology is crucial for understanding plant growth and climate feedback. It affects canopy structure, surface albedo, and carbon and water fluxes. While the influence of environmental factors on phenology is well‐documented, the role of plant intrinsic factors ...
Yunpeng Luo   +8 more
wiley   +1 more source

松嫩平原西部退化盐碱草地土壤酶活性的季节动态

open access: yesShuitu Baochi Xuebao, 2008
对松嫩平原西部退化盐碱草地土壤过氧化氢酶、过氧化物酶、多酚氧化酶、蛋白酶、转化酶及碱性磷酸酶活性的季节动态进行研究,结果表明:土壤过氧化物酶、蛋白酶和转化酶活性在碱斑及不同退化程度盐碱草地中的季节变化趋势不同,而过氧化氢酶、多酚氧化酶和碱性磷酸酶活性的季节变化趋势基本一致,其峰值出现在8月或9月;在不同退化程度的盐碱草地中,各种酶活性的季节变化幅度不同,过氧化氢酶、多酚氧化酶和碱性磷酸酶活性在中度、重度盐碱化草地中的变化幅度大于轻度盐碱化草地,而过氧化物酶、蛋白酶和转化酶活性在中度 ...
YUE, WANG, WANG, YAN
doaj  

A Novel Topical Emollient Plus for Canine Atopic Dermatitis: A Clinical Trial Assessing Efficacy and User Acceptance

open access: yesVeterinary Dermatology, Volume 37, Issue 2, Page 293-305, April 2026.
Background: Canine atopic dermatitis (cAD) is a common, chronic skin condition characterised by epidermal barrier dysfunction, immune dysregulation and cutaneous dysbiosis. While “emollient plus” formulations are widely used in human atopic dermatitis, their role in cAD remains underexplored. Hypothesis/Objectives: To evaluate the clinical efficacy and
Beatriz Fernandes   +8 more
wiley   +1 more source

长期免耕水稻田土壤的生物特征研究

open access: yesShuitu Baochi Xuebao, 2002
对经过 10年半旱式免耕定位试验的水稻土主要微生物类群数量和微生物生物量的变化进行对比研究 ,结果表明 :实行半旱式厢作及垄作免耕法能够迅速地提高土壤有机质、全氮、全磷和速效氮、磷的水平 ;微生物数量和微生物生物量变化一般存在季节性规律 :春季高 ,夏季至夏末降低 ;各处理土体上层和下层 (0~ 7.5 cm,7.5~15 cm)的基本肥力特征及微生物特征无明显区别 ;免耕处理土壤 ,其微生物的季节性变幅较小 ,垄上或厢上土壤微生物生物量甚至表现反季节性 ,整个生长季节内稳中有升 ...
张磊 肖剑英 等
doaj   +2 more sources

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