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Journal of Forestry Research 2020年第5期31卷 1479-1487页

作者： Ayse Deligoz Fatma Gokce Cankara Faculty of Forestry Isparta University of Applied Sciences32260 IspartaTurkey

Understanding how tree species respond to drought in their natural environment is needed to predict forest adaptation and management practices under global environmental *** study was carried out to determine and compare physiological and biochemical responses to variations in environmental conditions during summer drought of mixed natural stands of Pinus nigra ***(Lamb.)Holmboe and Pinus brutia *** xylem water potential(ψmd),water relations,photosynthetic pigments,total soluble sugar and proline contents were investigated during the growing season.ψmd followed a similar seasonal trend in both species but *** *** had higher ψmd than *** ψmd gradually decreased from June,reached its lowest value in August,and then increased *** decreases in the osmotic potential at turgor loss point(ψnTLP)were observed during the ***,ψnTLP was lower in *** soluble sugars decreased from April to June for ***,then increased and stayed relatively constant August to *** changes were found at lower values in *** *** accumulation and photosynthetic pigments were higher in *** results indicate that physiological and biochemical responses of both species against changing environmental conditions were in different degrees but followed similar *** *** is more sensitive to summer drought than *** in their natural environment.

关键词： Pinus nigra subsp.pallasiana Pinus brutia Osmotic potential Photosynthetic pigments Soluble sugars Proline summer drought

Analysis on the Climate Characteristics of summer drought Frequency in Chongqing

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Meteorological and Environmental Research 2010年第10期1卷 36-38页

作者：韩世刚苟思吉莉陈欢重庆市气象局重庆401147 兰州大学大气科学学院甘肃兰州73000

By using daily meteorological data from 34 surface meteorological stations in Chongqing from 1960 to 2006,the climate characteristics of summer drought in recent 47 years were analyzed by means of Morlet wavelet *** results revealed that summer drought in Chongqing showed obvious decrease trend on the whole,while extreme severe summer drought decreased firstly and then increased,especially since 1990s with obvious increase *** 1995 or 2004,there existed obvious oscillation period of 2-3 years in summer drought in Chongqing,and extreme severe summer drought was very stable without evident oscillation in 1906s,while there was obvious strong oscillation period of 4-5 years in extreme severe summer drought in Chongqing from 1970 to 1978.

关键词： summer drought Morlet wavelet analysis Matlab Chongqing China

Climate Characters of summer drought in Mountain City and the Effect on Flowers and Trees

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维普期刊数据库

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Agricultural Science & Technology 2012年第9期13卷 1991-1996页

作者：汪志辉李家启张爽吉莉郑定学刘斌重庆市北碚区气象局重庆400700 重庆市北碚区林业局重庆400700 重庆市北碚区农委重庆400700

[Objective] The aim was to provide references for development of industries engaging in flowers and trees in Beipei area in Chongqing. [Method] The occurring trend, intensity trend of summer drought, relationship of intensity with rainfall and extremely highest temperature, occurring trend during initial period of summer drought and the effects in mountain cities were analyzed, based on information on lasting period, rainfall, average temperature, extremely highest temperature of sum- mer drought in Beipei area in mountain cities during 1981-2010 and, growth condi- tion and phenological phenomena of Michelia champaca during 2005-2007. [Result] The occurring probability of summer drought in mountain cities was 57% and the probabilities of light, moderate, heavy and extreme drought were 30%, 10%, 7% and 10%; intensity of summer drought was none of linear relation with rainfall and ex- tremely highest temperature. In summer drought, daily average rainfall was less than 0.9 ram; extremely highest temperature was 35.0-45.0 ℃ with probability at 30%; initial period of summer drought was from later June to middle August and of extreme drought was later June-later July; the ending period was early September. During drought, when the extremely highest temperature （〉35.0 ℃） occurred in three days within a Hou, flowers and trees were affected by the hot drought and when the extreme temperature （〉40.0 ℃） occurred in three days within a Hou, the plants were seriously affected. [Conclusion] Based on characters of summer drought, pre- cautions can be taken to reduce effects of summer drought on flowers and trees with the help of weather forecast.

关键词： summer drought Flowers and trees Rainfall Average temperature andextremely highest temperature

Flowering Characteristics of Japonica Rice Male Sterile Lines Adaptive to High Temperature and summer drought

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Agricultural Science & Technology 2015年第8期16卷 1621-1627,1647页

作者：肖人鹏李经勇姚雄张现伟文明唐永群重庆市农业科学院/重庆再生稻研究中心重庆402160

[Objective] This study was conducted to screen japonica rice male sterile lines with good flowering characteristics under high temperature and summer drought. [Method] The flowering habits of 23 japonica male sterile lines, such as flowering peak, single-panicle flowering duration, single-plant flowering duration, en- closed glume rate, glume-opening angle, the distance between glumes, stigma exer- tion rate and sigma vitality, were compared with II-32A as a control under above weather condition. [Result] The flowering characteristics had significant difference a- mong the tested rice lines. Compared with the control, three japonica rice male ster- ile lines 35478A, 35489A and 35502A had better flowering traits, such as earlier flowering peak, longer single-panicle flowering duration, longer single-plant flowering duration, lower rate of enclosed glumes, larger glume angle and larger distance be- tween glumes. 35478A performed its flowering peak from 10：00-11：00 am, 1.5 h earlier than the control; 35489A exhibited higher stigma exertion rate, up to 76.23%; and 35502A had higher stigma vitality, up to 84.68%, which kept longer time than that of the CK. [Conclusion] The results will provide high-quality resources for the breeding of new japonica rice varieties with high-yield and high-temperature toler- ance.

关键词： Japonica rice Male Sterile line High temperature summer drought Flowering characteristic

Premature losses of leaf area in response to drought and insect herbivory through a leaf lifespan gradient

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Journal of Forestry Research 2022年第1期33卷 39-50页

作者： Sonia Mediavilla Montserrat Martínez-Ortega Santiago Andrés Javier Bobo Alfonso Escudero Departamento de Ecología Facultad de BiologíaUniversidad de Salamanca37071 SalamancaSpain Departamento de Botánica y Fisiología Vegetal Facultad de BiologíaUniversidad de Salamanca37071 SalamancaSpain

Implications of the differences in leaf life span are still subject to debate in the field of *** leaf traits associated with these differences may be decisive for determining the distribution of tree species,this topic is particularly relevant in the context of climate *** study analyzes the effects of the differences in leaf life span on premature losses of leaf area owing to insect herbivory and to abiotic *** of leaf area may be an important determinant of total leaf carbon *** Mediterranean tree species,distributed on four sites with different climates were *** species exhibited strong differences in leaf life span and in leaf traits,especially leaf mass per unit *** leaf area losses were estimated in response to insect herbivory and summer drought over two *** results revealed that,despite having older leaf cohorts with more damage,species with longer leaf duration had lower area lost to herbivores and less damage due to accelerated senescence during the summer *** respect to the predicted increase in water stress,deciduous species are at a disadvantage due to their high premature loss of leaf area and thus loss of photosynthetic capacity.

关键词： Accelerated senescence Insect herbivory Leaf life span Leaf structural reinforcement summer drought

Climate,female traits and population features as drivers of breeding timing in Mediterranean red deer populations

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Integrative Zoology 2017年第5期12卷 396-408页

作者： Marta PELÁEZ Alfonso SAN MIGUEL Carlos RODRÍGUEZ-VIGAL Ramón PEREA Department of Natural Systems and Resources Technical University of MadridMadridSpain National Parks Autonomous Agency MadridSpain Department of Biology Stanford UniversityStanfordCaliforniaUSA

Understanding the factors that lead to variation in the timing of breeding in widespread species such as red deer(Cervus elaphus)is crucial to predict possible responses of wild populations to different climate ***,we sought to further understand the causes of inter-annual variation in the reproduction timing of female deer in Mediterranean *** integrative approach was used to identify the relative importance of individual,population and climate traits in the date of conception of free-ranging deer,based on a dataset of 829 hinds culled during 12 *** found that a population trait,density,was the most important factor explaining the variation in conception dates,with greater densities causing later conception *** mass was the second in importance,with heavier females conceiving earlier than lighter *** equally important was the spring real bioclimatic index,a measure of plant productivity,causing later conception dates in the least productive springs(drier and hotter).Another climatic component,the end of summer drought,showed that the sooner the autumn arrives(greater rainfalls and cooler temperatures)the earlier the conception ***,age class was found to be a minor factor in determining conception *** older females(≥10 years old)conceived significantly later,suggesting reproductive *** study highlights not only the importance of population and individual traits but also the influence of climatic parameters on the deer reproductive cycle in Mediterranean environments,giving valuable insight into how reproductive phenology may respond to seasonality and global climate changes.

关键词： density-dependence mating short-day breeder summer drought ungulates