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How does tree age influence damage and recovery in forests impacted by freezing rain and snow?

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Science China(Life Sciences) 2015年第5期58卷 472-479页

作者： ZHU LiRong ZHOU Ting CHEN BaoMing PENG ShaoLin State Key Laboratory of Biocontrol Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education InstitutesSchool of Life Sciences Sun Yat-sen University

The response and recovery mechanisms of forests to damage from freezing rain and snow events are a key topic in forest research and management. However, the relationship between the degree of damage and tree age, i.e., whether seedlings, young trees, or adult trees are most vulnerable, remains unclear and is rarely reported. We investigated the effect of tree age on the degrees of vegetation damage and subsequent recovery in three subtropical forest types-coniferous, mixed, and broad-leaved —in the Tianjing Mountains, South China, after a series of rare icy rain and freezing snow events in 2008. The results showed that damage and recovery rates were both dependent on tree age, with the proportion of damaged vegetation increasing with age(estimated by diameter at breast height, DBH) in all three forest types and gradually plateauing. Significant variation occurred among forest types. Young trees in the coniferous forest were more vulnerable than those in the broad-leaved forest. The type of damage also varied with tree age in different ways in the three forest types. The proportion of young seedlings that were uprooted(the most severe type of damage) was highest in the coniferous forest. In the mixed forest, young trees were significantly more likely to be uprooted than seedlings and adult trees, while in the broad-leaved forest, the proportion of uprooted adult trees was significantly higher than that of seedlings and young trees. There were also differences among forest types in how tree age affected damage recovery. In the coniferous forest, the recovery rate of trees with broken trunks or crowns(DBH > 2.5 cm) increased with tree age. However, in the mixed and broad-leaved forests, no obvious correlation between the recovery rate of trees with broken trunks or crowns and tree age was observed. trees with severe root damage did not recover; they were uprooted and died. In these forests, vegetation damage and recovery showed tree age dependencies, which varied with

关键词： freezing rain and snow tree age damage restoration subtropical forest

Growth simulation and yield prediction for perennial jujube fruit tree by integrating age into the WOFOST model

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Journal of Integrative Agriculture 2020年第3期19卷 721-734页

作者： BAI Tie-cheng WANG Tao ZHANG Nan-nan CHEN You-qi Benoit MERCATORIS TERRA Teaching and Research Centre Gembloux Agro-Bio TechLiège UniversityGembloux 5030Belgium Southern Xinjiang Research Center for Information Technology in Agriculture/College of Information Engineering Tarim UniversityAlaer 843300P.R.China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key *** model was established using data collected from dedicated field experiments performed in *** growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,*** phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,*** addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same *** results showed the evolution of the simulated LAI and yields profiled in response to the changes in *** modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,*** proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.

关键词： fruit tree growth simulation yield forecasting crop model tree age

Size- and age-dependent increases in tree stem carbon concentration: implications for forest carbon stock estimations

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Journal of Plant Ecology 2020年第2期13卷 233-240页

作者： Su-Hui Ma Anwar Eziz Di Tian Zheng-Bing Yan Qiong Cai Min-Wei Jiang Cheng-Jun Ji Jing-Yun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China College of Life Sciences Capital Normal UniversityBeijing 100048China

Aims Forest biomass carbon(C)stocks are usually estimated by multiplying biomass by a C conversion factor,i.e.C ***,tree C concentration is crucial to the assessments of forest C *** stems contribute to the large fraction of tree biomass,the canonical value of 50%or other simplified values of stem C concentration are widely used to represent the values of tree C concentration in the estimations of forest C stocks at different ***,C concentration variations between tree organs and within tree size and their impacts on forest C stocks are still *** We conducted a global analysis of organ C concentration in age-specific trees based on 576 records of tree age,size(diameter at breast height and biomass)and C concentration data to evaluate the relationships between organ C concentrations and the changes of stem C concentration with tree age and *** Findings tree C concentration varied significantly with *** C concentration of trees was significantly correlated with that of other tree organs,except for barks and reproductive *** stem C concentration increased significantly with tree size and age,which contributed to the increases in C contents of stems and *** the C concentration in stems to represent the C concentrations of other organs and the whole tree could produce considerable errors in the estimations of forest C stocks(−8.6%to 25.6%and−2.5%to 5.9%,respectively).Our findings suggest that tree C accumulation in forests is related to the size-and age-dependent increases in stem C concentration and using specific C concentration values of tree organs can improve the estimations of forest C stocks.

关键词： tree organs carbon concentration forest carbon accounting tree size tree age

Aging Mongolian pine plantations face high risks of drought-induced growth decline:evidence from both individual tree and forest stand measurements

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Journal of Forestry Research 2024年第2期35卷 109-120页

作者： Mingyong Li Leilei Yang Yu Cao Dedong Wu Guangyou Hao CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China Key Laboratory of Terrestrial Ecosystem Carbon Neutrality Liaoning ProvinceShenyang 110016People’s Republic of China Daqinggou Ecological Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Research Institute of Sand Control and Utilization Liaoning ProvinceFuxin 123000People’s Republic of China

Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited *** important species for afforestation in dry environments of northern China,Mongolian pine(Pinus sylvestris *** Litv.)has recently exhibited growth decline and dieback on many sites,particularly pronounced in old-growth ***,changes in response to drought stress by this species with age as well as the underlying mechanisms are poorly *** this study,tree-ring data and remotely sensed vegetation data were combined to investigate variations in growth at individual tree and stand scales for young(9-13 years)and aging(35-52 years)plantations of Mongolian pine in a water-limited area of northern China.A recent decline in tree-ring width in the older plantation also had lower values in satellited-derived normalized difference vegetation indices and normalized difference water indices relative to the younger *** addition,all measured growth-related metrics were strongly correlated with the self-calibrating Palmer drought severity index during the growing season in the older *** of growth to drought of the older plantation might be attributed to more severe hydraulic limitations,as reflected by their lower sapwood-and leaf-specific hydraulic *** study presents a comprehensive view on changes of growth with age by integrating multiple methods and provides an explanation from the perspective of plant hydraulics for growth decline with *** results indicate that old-growth Mongolian pine plantations in water-limited environments may face increased growth declines under the context of climate warming and drying.

关键词： tree age Drought stress Mongolian pine plantation tree rings Remote sensing Plant hydraulics

Stability evaluation of radial growth of Picea schrenkiana in different age groups in response to climate change in the eastern Tianshan Mountains

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Journal of Mountain Science 2020年第7期17卷 1735-1748页

作者： JIAO Liang CHEN Ke WANG Sheng-jie LIU Xiao-ping College of Geography and Environment Science Northwest Normal UniversityLanzhou730070China

Global warming causes an unstable response in tree radial growth at high latitudes in the Northern ***,different climatic responses of different age groups of trees have been found due to their different physiological *** this study,the response stability and growth trend of three age groups(youngage groups were analyzed in the relatively dry climate of the eastern Tianshan *** results showed that:(1)With the abrupt increase in temperature in 1989,the annual mean minimum temperature became the dominant radial growth-limiting factor of the three age groups of Schrenk spruce.(2)The radial growth of the middle and young groups was more sensitive than that of the old group based on growth-climate correlation analysis.(3)The radial growth of the different age groups had different responses to climate factors,and all age groups were unstable on time scales.(4)The trend of the linear regression simulation of the basal area increment(BAI)indicated that the Schrenk spruce had the same growth trends in different age groups with growth first increased and then decreased;however,the decreased growth rate was higher in the middle and young age groups than in the old age group after the abrupt increase in ***,we should pay active attention to the impact of drought on Schrenk spruce in the eastern Tianshan Mountains and should particularly strengthen the conservation and management of the middle and young age groups.

关键词： Divergent response Global warming tree age Annual mean minimum temperature Schrenk spruce Tianshan Mountains

Activities of some defense proteins associated with age or plant family in larch needles of Larix olgensis and L. kaempferi× L. gmelinii

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Journal of Forestry Research 2017年第1期28卷 63-69页

作者： Zhaojun Meng Lili Tong Lulu Gao Shanchun Yan Yifang Lu College of Forestry Northeast Forestry University

Defence proteins are a kind of chemical defence compounds. They play a key role in plant restraining biotic and abiotic harm. To illuminate activities of some defense proteins associated with age or plant family of larch, the larch needles were collected from two different families of Korean larch, Larix olgensis and a hybrid larch, L. kaempferi × L. gmelinii, respectively, and then the activities of defence proteins in those were tested using a UV spectrophotometry. The results showed that the activities of protective enzymes at thel6-/17- and 19-year-age groups were higher than those at the other age groups in the both larch species. While the activities of polyphenol oxidase （PPO） at the 16-/17-year-age group and phenylalanine ammonia-lyase （PAL） and protease inhibitors at the 19-year-age group were the highest among all age groups. Then, compared with L. olgensis, the hybrid larch had significant effects on the activities of protective enzymes. The effects of plant family on the activities of PAL and chymotrypsin inhibitor were significantly different, and then those on the activities of PPO were not significantly different. The effects of the two families in L. olgensis on the activities of trypsin inhibitor （TI） were significantly different, while those in the hybrid larch on the activities of TI were contrary. To conclusions showed that the different age and plant family significantly affected the activities of defence proteins in the needles of two larch species, and then enhanced the larch resistance to pests. These could play a key function in forestry tree genetic improvement and management in future.

关键词： tree age Chemical defence Defenceprotein Larch Plant family

CPSDv0: a forest stand structure database for plantation forests in China

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Big Earth Data 2023年第1期7卷 212-230页

作者： Xiuchen Wu Xiaofei Jiang Hongyan Liu Craig Allen Xiaoyan Li Pei Wang Zongshan Li Yuting Yang Shulei Zhang Fangzhong Shi Jiaojun Zhu Pengtao Yu Mei Zhou Pengwu Zhao Yanhui Wang Chao Yue Deliang Chen State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingChina School of Natural Resources Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina College of Urban and Environmental Sciences and MOE Laboratory for Earth Surface Processes Peking UniversityBeijingChina U.S.Geological Survey-Nebraska Cooperative Fish&Wildlife Research Unit School of Natural Resources423 Hardin HallUniversity of NebraskaLincolnNEUSA State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijingChina CAS Key Laboratory of Forest Ecology and Management Qingyuan Forest CERNInstitute of Applied EcologyChinese Academy of SciencesShenyangChina Key Laboratory of Forest Ecology and Environment of the National Forestry and Grassland Administration of China Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of ForestryBeijingChina Academy of Forestry Inner Mongolia Agricultural UniversityHuhhotChina State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYanglingShaanxiChina Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburgSweden

Forest stand structure is not only a crucial factor for regulating forest functioning but also an important indicator for sustainable forest management and ecosystem *** there exists a few national/global structure databases for natural forests,a country-wide synthetic structure database for plantation forests over China,the world’s largest player in plantation forests,has not been *** this study,we built a country-wide synthetic stand structure database by surveying more than 600 peer-reviewed *** database covers tree species,mean stand age,mean tree height,stand density,canopy coverage,diameter at breast height,as well as the associated ancillary in-situ topographical and soil properties.A total of 594 pub-lished studies concerning diverse forest stand structure parameters were compiled for 46 tree *** first synthesis for stand structure of plantation forests over China supports studies on the evolution/health of plantation forests in response to rapid climate change and intensified disturbances,and benefits country-wide sustainable forest management,future afforestation or reforestation *** users include those studying forest community dynamics,regional tree growth,ecosystem stability,and health,as well as those working with conservation and sustainable *** dataset is freely acces-sible at http://***/10.11922/sciencedb.j00076.00091.

关键词： Stand structure plantation tree age tree height stand density canopy coverage

Ice Storm Damage in an Extreme Climate Event in Subtropical Forest Region:a Case Study from Tianjing Mountain,China

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Ice Storm Damage in an Extreme Climate Event in Subtropical ...

广东省植物学会第十九期学术研讨会

作者： Lirong Zhu,Zhenguang Lin,Leiyi Chen,Keke Wu,Yawen Xu,Shaolin Peng~* (School of Life Sciences and State Key laboratory of Biocontrol,Sun Yat-sen University, Guangzhou 510006,P.R.China)

Extreme climate events are predicted to be more frequent as one disastrous factor to *** they cause damages to subtropical forest remains *** addition,the potential relationships of forest resistance and the community characters are less with concerned. This study was conducted to determine how tree species,tree age,forest type and community diversity influences the subtropical forest damages to extreme ice *** tree suffered heaviest damage;Broad-leaved trees less *** damage rate of trees increased with the tree age,i.e.,the damage rate of the seeding trees(DBHtrees(2.5trees(DBH>7.5 cm) were damaged by the extreme ice *** mechanical damage modes(uprooting,stem breakage,crown breakage and stem bending) were closely related to the DBH,especially in broad-leaved *** damage rate of forest was closely related to the community diversity,the broad-leaved forest with the highest species diversity showed strongest resistance to the ice storm,while the coniferous forest was the least resistant to the damage,which had lowest community *** forests were rebuilt,people should enhance community diversity to combat extreme weather *** Lanceolata was the most susceptible,and Eurya were endured to the ice storm in southern China. As extreme event like ice storm may become frequent in future,big trees should be paid more attention because they are more susceptibility to ice storm.

关键词： community diversity extreme event forest damage forest type ice storm subtropical forest tree age

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缺血性脑卒中治疗的药物经济学研究

缺血性脑卒中治疗的药物经济学研究

作者：孟欣广东药科大学

学位级别：硕士

目的:目前缺血性脑卒中已经成为我国第一位的致死疾病,并且发病年龄还在年轻化。缺血性脑卒中不仅对患者造成严重伤痛,还影响了患者家庭的和谐与经济,对社会和国家也产生一定影响。本文对影响患者治疗的自身因素进行统计分析;对临床上... 详细信息

目的:目前缺血性脑卒中已经成为我国第一位的致死疾病,并且发病年龄还在年轻化。缺血性脑卒中不仅对患者造成严重伤痛,还影响了患者家庭的和谐与经济,对社会和国家也产生一定影响。本文对影响患者治疗的自身因素进行统计分析;对临床上治疗缺血性脑卒中使用的中药注射剂、神经保护剂、抗血小板药物进行药物经济学分析。为临床治疗缺血性脑卒中提供参考信息,选择最佳诊疗方案,进而达到合理用药的目的。为政府工作部门、药库、药剂科、临床科室提供参考信息,为基本医疗保险药品目录的遴选提供参考,使得有限的卫生资料得到合理利用,卫生政策法规的制定更加科学合理。方法:本研究采用回顾性分析方法对神经内科缺血性脑卒中住院患者的临床病例进行收集整理,对初次住院和再次住院患者的年龄、是否患高血压、是否患糖尿病、是否患其他心脏病、是否吸烟、是否饮酒的因素进行NIHSS量表评分(美国国立卫生院神经功能缺损评分)、住院天数、总费用的统计学分析。并对缺血性脑卒中诊治指南撰写的《中国急性缺血性脑卒中诊治指南》(2014年)关于中医中药、神经保护、改善脑血循化的具体药物进行药物经济学分析。分别选用丹参多酚酸盐注射液(丹参组)与川芎嗪注射液(川芎组)、阿托伐他汀钙片(阿托伐组)与瑞舒伐他汀钙片(瑞舒伐组)、阿司匹林肠溶片(阿司组)与阿司匹林肠溶片联用氯吡格雷片(阿+氯组),对患者基本情况进行统计学分析;对每组药物的治疗效果进行比较,在治疗效果相同的情况下,使用药物经济学中最小成本法得出最优治疗药物,并对每组治疗药物进行敏感性分析。每组药物均使用决策树tree age模型软件分析,将每组药物的治疗结果发生的概率和花费的直接成本表现出来,决策树tree age模型软件分析使得药物经济学分析结果清晰准确表达。结果:患者基本情况中分析的因素对治疗缺血性脑卒中具有一定的影响。初诊组患者中年龄A组的出院情况明显好于年龄B组和年龄C组的患者,并且年龄A组患者住院天数明显小于年龄C组的患者;再诊组患者中年龄A组出院情况明显好于年龄B组和年龄C组,年龄A组住院天数明显小于年龄B组,年龄A组住院总费用明显小于年龄B组和年龄C组,年龄C组出院情况明显好于年龄B组。年龄C组住院天数明显小于年龄B组。年龄C组住院总费用明显小于年龄B组。年龄A组患者中再诊组患者的住院总费用明显小于初诊组患者。年龄B组患者中初诊组患者的出院NIHSS明显小于再诊组患者;初诊组患者高血压组的入院情况较非高血压组轻,出院情况优于非高血压组。再诊组患者非高血压组的出院情况好于高血压组;初诊组患者中糖尿病组的住院天数明显高于非糖尿病组。再诊组患者中糖尿病组的出院情况较非糖尿病组差,住院总费用较非糖尿病组高;再诊组患者中其他心脏病组患者的住院天数明显大于非其他心脏病组;初诊组患者中吸烟组患者的住院天数明显大于非吸烟组;初诊组患者中饮酒组患者的住院天数明显大于非饮酒组;中药组:中药注射液是丹参多酚酸盐注射液(丹参组)和川芎嗪注射液(川芎组),丹参组总有效率为91.30%,川芎组总有效率为90.90%,丹参组每人成本2259.8元,川芎组每人成本521.4元,最小成本显示川芎组优于丹参组,并与敏感性分析结果一致;神经保护剂:他汀类药物是阿托伐他汀钙片(阿托伐组)和瑞舒伐他汀钙片(瑞舒伐组),阿托伐组总有效率为88.98%,瑞舒伐组总有效率为92.31%,阿托伐组每人成本119.24元,瑞舒伐组每人成本89.6元,最小成本显示瑞舒伐组优于阿托伐组,并与敏感性分析结果一致;改善脑血循环:抗血小板药物是阿司匹林肠溶片(阿司组)和阿司匹林肠溶片联合氯吡格雷片(阿+氯组),阿司组总有效率为92.00%,阿+氯组总有效率为94.34%,阿司组每人成本6.05元,阿+氯组每人成本152.9元,最小成本显示阿司组优于阿+氯组,并与敏感性分析结果一致。结论:本研究证明了年龄、高血压、糖尿病、其他心脏病、吸烟、饮酒对治疗缺血性脑卒中具有一定影响,对于缺血性脑卒中的治疗和预防提供参考依据。从临床治疗缺血性脑卒中诊疗方案中的药物进行药物经济学分析,初步得到最优治疗用药方案。运用药物经济学分析方法证明了川芎组优于丹参组、瑞舒伐组优于阿托伐组、阿司组优于阿+氯组。本研究结果为临床治疗药物的选择提供药物经济学依据。为医生和患者对于缺血性脑卒中预防和干预的用药方案提出参考,合理有效降低患者治疗药物的经济负担。为临床缺血性脑卒中治疗药物的基本医疗保险药品目录的遴选提供参考,推动安全、合理、有效、经济的用药政策方针。

关键词：缺血性脑卒中 NIHSS tree age 药物经济学