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The contributions of nitrification and denitrification to N2O and N2 emissions from four forest soils on northern slop of Changbai Mountain were measured with acetylene inhibition methods. In
incubation experiments, 0.06% and 3% C2H2 were used to inhibit nitrification and denitrification in these soils, respectively. Both nitrification and denitification
existed in these soils except tundra soil, where only denitrification was found. The annually averaged rates of nitrification
and denitrification in mountain dark brown forest soil were much higher than that in other three soils. In mountain brown
coniferous soil, contributions of different processes to gaseous nitrogen emissions were Denitrification N2O>nitrification N2O>Denitrification N2. The same sequence exists in mountain soddy soil as that in the mountain brown coniferous soil. The sequence in mountain
tundra soil was Denitrification N2O>Denitrification N2.
Foundation item: This paper was supported by the National Natural Science Foundation of China (No.49701016) and the “Hundred Scientists”
Project of Chinese Academy of Sciences.
Biography: XU Hui (1967-), male, Ph. Doctor, associate research fellow in Laboratory of Ecological Process of Trace Substance in Terrestrial
Ecosystem, Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110015, P. R. China.
Responsible editor: Song Funan 相似文献
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本文以Landsat TM影像数据为基础,采用基于支持向量机分类方法对长白山地区大荒沟林场进行森林植被信息提取,并与传统的最大似然法分类进行对比。结果表明,基于支持向量机方法的森林信息提取精度,Kappa值分别为0.981 0、0.971 6、0.975 3,均超过了最大似然法(MLC)的提取精度和Kappa值0.963 4。该方法有很好的操作性和实用性,准确度满足了林业规划设计的基础数据材料精度要求。 相似文献
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Betula ermanni population was divided into three groups: the upper population (2 000–2 200 m), the middle population (1 700–2 000 m), and
the down population (1 400–1 700 m) in Changbai Mountain. The dynamics ofBetula ermanni populations in subalpine vegetation are studied and the population life table, fecundity schedule, survival curves, age structure,
and fecundity curves were established. The results showed that the, middle population is obviously, the transition from the
upper population to the down population.
This project is supported by Chinese Academy of Science
Responsible editor 相似文献
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lntroductionNotonIyaretimberIinesthemostconspicuousvegetationboundaryinhighmountains,buttheyareaIsoanimportantecologicaIboundary(Bruce1996,Thomas1997).NowondersthenthosetimberIineshaveaIwaysattractedresearchersforbothscientificandpracticaIreasons.InChangbaiMountain,forexample,therestorationoftheclimatictimberlineandestabIishmentofanedectiveprotectiveforestarethetWoprincipalobjectivesofhigh-mountainfor-estmanagement.AIsointhisconnection,thepotentiaIresponseoftimberlinestoexpectedclimaticc… 相似文献
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利用扩散法测定草甸土、淡黑钙土、草甸黑钙土及盐碱土碱解氮含量,结果表明:添加与不添加还原剂测定的土壤碱解氮含量,在8~24 h之间,呈上升态势,在24~30 h之间有所下降,但在30~48 h之间又呈现明显上升趋势,在扩散时间为24 h时氮含量测定值达到最好。添加与未添加还原剂所测得的土壤碱解氮含量相关极显著,进而证明两种方法都适用于这4种土壤的测定。还原剂对草甸土、淡黑钙土、草甸黑钙土碱解氮含量的测定影响不大,但在测定盐碱土碱解氮含量时采用添加还原剂的方法更加准确。 相似文献
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Composition and mineralization of soil organic carbon pools in four single-tree species forest soils
Forest soil carbon(C) is an important component of the global C cycle. However, the mechanism by which tree species influence soil organic C(SOC) pool composition and mineralization is poorly understood. To understand the effect of tree species on soil C cycling, we assessed total, labile, and recalcitrant SOC pools, SOC chemical composition by ~(13) C nuclear magnetic resonance spectroscopy, and SOC mineralization in four monoculture plantations. Labile and recalcitrant SOC pools in surface(0–10 cm) and deep(40–60 cm) soils in the four forests contained similar content. In contrast, these SOC pools exhibited differences in the subsurface soil(from 10 to20 cm and from 20 to 40 cm). The alkyl C and O-alkyl C intensities of SOC were higher in Schima superba and Michelia macclurei forests than in Cunninghamia lanceolata and Pinus massoniana forests. In surface soil, S.superba and M. macclurei forests exhibited higher SOC mineralization rates than did P. massoniana and C.lanceolata forests. The slope of the straight line between C_(60) and labile SOC was steeper than that between C_(60) and total SOC. Our results suggest that roots affected the composition of SOC pools. Labile SOC pools also affected SOC mineralization to a greater extent than total SOC pools. 相似文献
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2009年7月至8月,在湖南省植物园用树脂芯原位测定法,比较了樟树和马尾松群落土壤中无机氮含量及氮矿化速率。结果表明:培养前2种群落土壤中无机氮差异显著(P0.05),呈现马尾松樟树的规律,其中NH4+-N分别占群落土壤无机氮的98.2%和93.69%,是无机氮的主要存在形式;经过14、28和42 d的培养,樟树和马尾松群落土壤中NH4+-N和NO3--N含量均发生显著的变化(P0.01),NH4+-N的含量均呈现出先下降后上升的规律,NO3--N含量则表现出不同的规律,樟树群落为上升,马尾松群落为先下降后上升;樟树群落净氮矿化量为-(33.82±3.48)、-(16.81±5.90)和(29.14±4.41)mg.kg-1,马尾松群落为-(59.93±3.48)、-33.17和-13.11 mg.kg-1。 相似文献
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不同强度间伐对长白山天然林林下植物多样性的影响 总被引:1,自引:0,他引:1
对吉林森工集团松江河林业局辖区内的阔叶红松林、杂木林和杨桦林采取30%~40%(T1)、20%(T2)株数强度的均匀间伐处理,以不间伐处理为对照(CK),对间伐2 a后林下植物木本、草本植物进行调查,采用Simpson、Shannon-Wiener多样性指数和Pielou均匀度指数进行植物多样性分析,探讨不同强度间伐对3个林型林下植物多样性的影响。研究结果表明:T1间伐后3个林型的物种丰富度均有增加(杂木林木本植物例外),T2间伐后杨桦林木本植物丰富度降低,草本植物丰富度增加。两种间伐处理均增加阔叶红松林木本植物多样性,T1处理尤为明显。T1处理增加杂木林和杨桦林木本植物多样性,而T2间伐处理有较弱的降低作用。两种间伐处理均降低阔叶红松林和杂木林草本植物多样性,与强度无明显关系。随着间伐强度的增加杨桦林草本植物多样性增大。在长白山天然林中,较大间伐强度T1(30%~40%)能够有效提高植物多样性。 相似文献
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Carbohydrate represents an important part of the soil labile organic carbon pool. Water soluble carbohydrate drives the C cycle in forest soil by affecting microbial activity and hot water extractable carbohydrate is thought related to soil carbon sequestration due to the association with soil aggregation. In a temperate forest region of northeast China, Changbai Mountain, we investigated the abundance, spacial distribution, and seasonal dynamics of cool and hot-water extractable carbohydrate in soils under mixed broad-leaved Korean pine forest. The concentrations of cool-water extractable carbohydrate (CWECH) in three soil layers (0-5, 5-10, 10-20 cm) ranged from 4.1 to 193.3 g·kg-1 dry soil, decreasing rapidly with soil depth. On an annual average, the CWECH concentrations in soils at depths of 5-10 and 10-20 cm were 54.2% and 24.0%, respectively, of that in the 0-5 cm soil layer. CWECH showed distinct seasonal dynamics with the highest concentrations in early spring, lowest in summer, and increasing concentrations in autumn. Hot-water extractable carbohydrate (HWECH) concentrations in three soil layers ranged from 121.4 to 2026.2 g·kg-1 dry soil, which were about one order of magnitude higher than CWECH. The abundance of HWECH was even more profile-dependent than CWECH, and decreased more rapidly with soil depth. On an annual average, the HWECH concentration in soils 10-20 cm deep was about one order of magnitude lower than that in the top 0-5 cm soil. The seasonality of HWECH roughly tracked that of CWECH but with seasonal fluctuations of smaller amplitude. The carbohydrate concentrations in cool/hot water extracts of soil were positively correlated with UV254 and UV280 of the same solution, which has implications for predicting the leaching loss of water soluble organic carbon. 相似文献
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One-year-old seedlings of Pinus koraiensis, Pinus sylvestriformis, Phellodendron amurense were grown in open-top chambers (OTCs) with 700 and 500 mmol/mol CO2 concentrations, control chamber and on open site (ambient CO2, about 350 mmol/mol CO2) respectively at the Open Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, and the growth course responses of three species to elevated CO2 and temperature during one growing season was studied from May to Oct. 1999. The results showed that increase in CO2 concentration enhanced the growth of seedlings and the effect of 700 mmol/mol CO2 was more remarkable than 500 mmol/mol CO2 on seedling growth. Under the condition of doubly elevated CO2 concentration, the biomass increased by 38% in average for coniferous seedlings and 60% for broad-leaved seedlings. With continuous treatment of high CO2 concentration, the monthly-accumulated biomass of shade-tolerant Pinus koraiensis seedlings was bigger in July than in August and September, while those of Pinus sylvestriformis and Phellodendron amurense seedlings showed an increase in July and August, or did not decrese until September. During the hot August, high CO2 concentration enhanced the growth of Pinus koraiensis seedlings by increasing temperature, but it did not show dominance in other two species. 相似文献
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以长白山主要支脉张广才岭和哈达岭山系为研究对象,通过对各林分类型凋落物现存量及其组成分析,探讨不同林分类型凋落物现存量的差异.结果表明,天然林凋落物平均现存量为5.97 t/hm2;人工林凋落物平均现存量为5.96 t/hm2;在天然林各调查群落中,阔叶混交林和落叶阔叶纯林面积占有较大比例,凋落物平均现存量分别为6.11和5.99 t/hm2;其针叶混交林面积最小,平均现存量仅为2.74 t/hm2;在人工林各调查群落中,针叶纯林面积最大,平均现存量为6.09 t/hm2;针阔混交林面积最小,平均现存量为5.76 t/hm2.在人工林、天然林未分解层各组分中,均表现出凋落叶(阔叶+针叶)>凋落枝(阔枝+针枝)>杂物的趋势. 相似文献
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One-year-old seedlings ofPinus koraiensis, Pinus sylvestriformis, Phellodendron amurense were grown in open-top chambers (OTCs) with 700 and 500 ώmol/mol CO2 concentrations, control chamber and on open site (ambient CO2, about 350 ώmol/mol CO2) respectively at the Open Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, and the growth
course responses of three species to elevated CO2 and temperature during one growing season was studied from May to Oct. 1999. The results showed that increase in CO2 concentration enhanced the growth of seedlings and the effect of 700 (ώmol/mol CO2 was more remarkable than 500 ώmol/mol CO2 on seedling growth. Under the condition of doubly elevated CO2 concentration, the biomass increased by 38% in average for coniferous seedlings and 60% for broad-leaved seedlings. With
continuous treatment of high CO2 concentration, the monthly-accumulated biomass of shade-tolerantPinus koraiensis seedlings was bigger in July than in August and September, while those ofPinus sylvestriformis andPhellodendron amurense seedlings showed an increase in July and August, or did not decrese until September. During the hot August, high CO2 concentration enhanced the growth ofPinus koraiensis seedlings by increasing temperature, but it did not show dominance in other two species.
Foundation Item: This paper was supported by Chinese Academy of Sciences and the Open Research Station of Changbai Mountain Forest Ecosystem. 相似文献
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长白山自然保护区蝴蝶区系研究 总被引:2,自引:0,他引:2
2003~2006年对长白山保护区蝴蝶种类进行了多次系统调查,共采集蝴蝶100种,隶属于7科59属,区系成分以广布种为主,各林带蝴蝶种类以红松阔叶林最多,苔原带最少,体现了环境变化对蝴蝶种类分布的影响。 相似文献
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分析了休闲旅游业的形象产业属性与价值,探讨了长白山科学文化资源与旅游形象定位,对长白山休闲旅游地旅游形象的传播进行了研究,指出了长白山休闲旅游景区的导游产品及导游服务要成为长白山旅游形象的传播者,以此树立长白山国际休闲旅游名山的科学形象、文化形象、诚信友善的形象,获得满意体验的旅游者是旅游景区形象的最忠实的传播者。 相似文献