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The Heart of the forest

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小学生时代(大嘴英语) 2025年第2期 12-17页

Ava and Liam live in a small *** people there get sick but don't know *** day,Ava and Liam find an old box under a big tree in the *** think it may help the *** they get to the cave,Ava steps back,“I can’t do it It... 详细信息

关键词： forest steps forest.

Carbon budgets of three temperate forest.ecosystems in Dongling Mt.,Beijing,China

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Science China Earth Sciences 2007年第1期50卷 92-101页

作者： FANG JingYun LIU GuoHua ZHU Biao WANG XiaoKe LIU ShaoHui Department of Ecology College of Environmental Sciences and Key Laboratoryfor Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China

There is a general agreement that forest.ecosystems in the NorthernHemisphere function as significant sinks for atmospheric CO_2; however, their magnitude anddistribution remain large uncertainties. In this paper, we report the carbon (C) stock and itschange of vegetation, forest.floor detritus, and mineral soil, annual net biomass increment andlitterfall production, and respiration of vegetation and soils between 1992 to 1994, for threetemperate forest.ecosystems, birch (Betula platyphylla) forest. oak (Ouercus liaotungensis) forest.nd pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the Cbudgets of these forest.ecosystems. Our results indicated that total C density (organic C perhectare) of these forest. ranged from 250 to 300 t C ha^(-1), of which 35—54 t C ha^(-1) fromvegetation biomass C and 209-244 t C ha^(-1) from soil organic C (1 m depth, including forest.floordetritus). Biomass C of all three forest. showed a net increase, with 1.33—3.55 t C ha^(-1) a^(-1)during the study period. Litterfall production, vegetation autotrophic respiration, and soilheterotrophic respiration were estimated at 1.63—2.34,2.19—6.93, and 1.81 —3.49 t C ha^(-1)a^(-1), respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t Cha^(-1) a^(-1), about half of which (46%-59%, 3.20-5.89 t C ha^(-1) a^(-1)) was converted to netprimary production. Our results suggested that pine forest.fixed C of 4.08 t ha^(-1) a^(-1), whereassecondary forest. (birch and oak forest. were nearly in balance in CO_2 exchange between theatmosphere and ecosystems.

关键词： carbon budget carbon density carbon flux mountainous area temperate forest.

A comparison between simulated and measured CO_2 and water flux in a subtropical coniferous forest

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Science China Earth Sciences 2006年第S2期49卷 241-251页

作者： GU Fengxue, CAO Mingkui, WEN Xuefa, LIU Yunfen & TAO Bo Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Using data from eddy covariance measurements in a subtropical coniferous forest. a test and evaluation have been made for the model of Carbon Exchange in the Vegetation-Soil-Atmosphere (CEVSA) that simulates energy transfers and water, carbon and nitrogen cycles based on ecophysiological processes. In the present study, improvement was made in the model in calculating LAI, carbon allocation among plant organs, litter fall, decomposition and evapotranspiration. The simulated seasonal variations in carbon and water vapor flux were consistent with the measurements. The model explained 90% and 86% of the measured variations in evapotranspiration and soil water content. However, the modeled evapotranspiration and soil water content were lower than the measured systematically, because the model assumed that water was lost as runoff if it was beyond the soil saturation water content, but the soil at the flux site with abundant rainfall is often above water saturated. The improved model reproduced 79% and 88% of the measured variations in gross primary production (GPP) and ecosystem respiration (Re), but only 31% of the variations in measured net ecosystem exchange (NEP) despite the fact that the modeled annual NEP was close to the observation. The modeled NEP was generally lower in winter and higher in summer than the observations. The simulated responses of photosynthesis and respiration to water vapor deficit at high temperatures were different from measurements. The results suggested that the improved model underestimated ecosystem photosynthesis and respiration in extremely condition. The present study shows that CEVSA can simulate the seasonal pattern and magnitude of CO2 and water vapor fluxes, but further improvement in simulating photosynthesis and respiration at extreme temperatures and water deficit is required.

关键词： ecosystem CO2 and water flux CEVSA eddy covariance subtropical coniferous forest.

The Research on the Distribution, Abundance and Some Ecological Characteristics of Neuroterus Species （Hymenoptera： Cynipidae） in Oak forest.of West Azerbaijan （Iran）

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Journal of Life Sciences 2011年第8期5卷 625-633页

作者： Mohammed Reza Zargaran Mohammed Hassan Safaralizadeh Ali Asghar Pourmirza Esmaeil Alizadeh Department of Plant Protection Faculty of Agriculture Uremia University Uremia West Azerbao＇an P.O. Box 165 Iran Agricultural and Natural Resources Center of West Azerbao＇an Uremia P. O. Box 365 Iran

Oak gall wasps （Hymenoptera： Cynipidae）, with more than 1300 species, represent one of the largest radiations of gall inducing insects. Many studies have documented galling species lists and richness, especially gall wasps, but few studies have been directed toward understanding how the gall-inducing species are locally distributed. In this survey, the oak gall wasps were collected from April to November （2009 and 2010） in West Azerbaijan of Iran. Among these collected galls, five species of oak gall wasps which belonged to the genus Neuroterus sp. were identified as： Neuroterus lanuginosus Giraud, N. numismalis Geoffroy, N. saliens Kollar, N. laeviusculus Schenck and N. quercus-baccarum Linnaeus. All of the galls in this survey are leaf galls. These galls were produced by the asexual reproduction and were collected in summer and fall seasons. The highest species richness was recorded in Ghabre-hossein and Vavan stations. Also, the highest density of gall formation was recorded at the southern direction. The multiple-sites similarity measures indicated that similarity in gall composition and community between collecting sites was generally between 0.57 and 0.90. The highest multiple site similarity was recorded between Vavan vs Rabat vs Dare-ghabr station. The authors showed that the very cold and humidity climate is not appropriate to Neuroterus species activity and the south direction is the best side for their survival.

关键词： Oak gall wasps distribution population Neuroterus sp. forest.

Meteorological control on CO_2 flux above broad-leaved Korean pine mixed forest.in Changbai Mountains

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Science China Earth Sciences 2005年第z1期48卷 116-122页

作者： GUAN Dexin, WU Jiabing, YU Guirui, SUN Xiaomin, ZHAO Xiaosong, HAN Shijie & JIN Changjie Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The impacts of temperature, photosynthetic active radiation (PAR) and vapor pressure deficit (VPD) on CO2 flux above broad-leaved Korean pine mixed forest.in the Changbai Mountains were studied based on eddy covariance and meteorological factors *** results showed that, daytime CO2 flux was mainly controlled by PAR and they fit Michaelis-Menten equation. Meanwhile VPD also had an influence on the daytime flux. Drier air reduced the CO2 assimilation of the ecosystem, the drier the air, the more the reduction of the assimilation. And the forest.was more sensitive to VPD in June than that in July and August. The respiration of the ecosystem was mainly controlled by soil temperature and they fit exponential equation. It was found that this relationship was also correlated with seasons; respiration from April to July was higher than that from August to November under the same temperature. Daily net carbon exchange of the ecosystem and the daily mean air temperature fit exponential equation. It was also found that seasonal trend of net carbon exchange was the result of comprehensive impacts of temperature and PAR and so on. These resulted in the biggest CO2 uptake in June and those in July and August were next. Annual carbon uptake of the forest.ecosystem in 2003 was -184 gC. m-2.

关键词： CO2 flux, soil temperature, PAR, broad-leaved Korean pine mixed forest.

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The Golden Antelope

英语角 2022年第7期 44-49页

*** upona time,there was a golden antelope living in the *** she stamped(跺)herfoot,gold coins could fall *** king knew this andwanted to catch her.

关键词： Golden forest. golden

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英语角 2022年第6期 34-35页

作者： Kay 不详

Lisa is walking through the ***!There's a huge cat there!What is the cat doing?What is going on between them?这只巨大的猫咪和丽莎之间会发生什么故事呢?大家可以开动脑筋,发挥创意,续写属于自己的故事哦!请大家将接下来会发... 详细信息

Lisa is walking through the ***!There's a huge cat there!What is the cat doing?What is going on between them?这只巨大的猫咪和丽莎之间会发生什么故事呢?大家可以开动脑筋,发挥创意,续写属于自己的故事哦!请大家将接下来会发生的事写成一篇100-250个单词的小文章,寄到杂志社与大家分享吧!

关键词： What 丽莎 forest.

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联想作文

英语角 2022年第21期 48-49页

作者： Penny 不详

Look!There's a girl lying in the *** her side are two elves(精灵)and *** are they?Why are they there?这个女孩为什么在森林里?那两个小精灵又和她是什么关系呢?大家可以开动脑筋,发挥创意,续写属于自己的故事哦!请大家将接下来... 详细信息

Look!There's a girl lying in the *** her side are two elves(精灵)and *** are they?Why are they there?这个女孩为什么在森林里?那两个小精灵又和她是什么关系呢?大家可以开动脑筋,发挥创意,续写属于自己的故事哦!请大家将接下来会发生的事写成一篇100-250个单词的小文章,寄到杂志社与大家分享吧!

关键词： forest. lying rabbit.