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Pest and disease incidence of coniferous species in Taman Saujana Hijau,Putrajaya urban park,Malaysia
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作者 Nura Adila Shamsul Kamar Siti Khadijah Abd Rahim +5 位作者 Annya Anak Ambrose Norida Hanim Awing Zaiton Samdin Aff endy Hassan Mohd Nazre Saleh Razak Terhem 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期2065-2077,共13页
Taman Saujana Hijau(TSH),Putrajaya is a 41-ha urban park planted with various coniferous species from around the world.Insect pests and disease incidences of this park are unknown and there is a need for an evaluation... Taman Saujana Hijau(TSH),Putrajaya is a 41-ha urban park planted with various coniferous species from around the world.Insect pests and disease incidences of this park are unknown and there is a need for an evaluation of the health status of this urban park.This study assessed the level of pest and disease incidents of coniferous species in 12 plots of 7 species(Araucaria bidwilii,Araucaria haterophylla,Araucaria cunninghamii,Pinus caribaea,Pinus merkusii,Podocarpus polystachyus,and Podocarpus costalis).Termites,canker disease,and foliar disease are three major problems.The highest pest and disease incidence(PnDI)was foliar disease with a 0.49 coefficient correlation between the total number of trees and the PnDI,followed by canker disease with 0.40,and termites with 0.36.Of the seven conifers,A.haterophylla was the most infected followed by A.bidwilii and A.cunninghamii.It was concluded that the incidence of pests and diseases in TSH was moderate.To our knowledge,this may be the first baseline inventory of pests and diseases of coniferous species in Malaysia. 展开更多
关键词 Canker disease coniferous species Foliar disease Pest and disease incidence Urban park
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Remote Sensing Monitoring of the Subalpine Coniferous Forests and Quantitative Analysis of the Characteristics of Succession in East Mountain Area of Tibetan Plateau——A Case Study With Zamtang County 被引量:5
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作者 张学儒 张镱锂 +2 位作者 刘林山 张继平 高俊刚 《Agricultural Science & Technology》 CAS 2011年第6期926-930,共5页
The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation... The study area lies in the Dadu River drainage area in upstream Yangtze River.The spatial distribution of subalpine coniferous forests in 1989 and 2009 was extracted by means of a combined method of object orientation and visual interpretation,and then the overlaying analysis of these data was conducted.The type and spatial location of succession were discovered and served as the sample of dependant variable.Meanwhile,supported by GIS technology and based on DEM and thematic data,the eight variables including altitude,slope,sin and cosin of aspect,curvity of land surface,and distance to residential area,cultivated land and road were extracted served as the sample of spatial succession of subalpine coniferous forests to fit Logistic Regression,and then the contribution of each independent variable as well as the spatial property of the occurrence probability of succession was calculated.The results suggested that,during the succession of subalpine coniferous forests to meadow,the closer to the residential area and cultivated land,the greater the contribution to succession is.In particular,when the distance to the residential area decreases by one unit,the probability for its conversion to meadow will be increased by 1.15 times.During the succession of subalpine coniferous forests to deciduous-broadleaved shrubs,the sin of aspect and distance to residential area contribute more,and the probability of succession increases with increasing degree of northwardness,i.e.when the degree of northwardness increases by one unit,the probability will be increased by 1.2 times.The quantitative analysis of spatial succession property of subalpine coniferous forests will supply scientific basis to the protection and restoration of subalpine coniferous forests. 展开更多
关键词 Subalpine coniferous Forests Logistic Regression GIS East Mountain Area of Tibetan Plateau
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Water holding effect of subalpine dark coniferous forest soil in Gongga Mountain, China 被引量:2
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作者 常志华 陆兆华 关文彬 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期205-209,共5页
Because of the distinction of soil property and humus content, soil water content is not ideal to indicate whether it is suitable to the growth of plant. Mainly based on the PF-a numerical value denoting the water reg... Because of the distinction of soil property and humus content, soil water content is not ideal to indicate whether it is suitable to the growth of plant. Mainly based on the PF-a numerical value denoting the water regime of soil and connected with the growth of plant, the study combined the moisture percentage of soil with PF to research in quantity the interrelation between the moisture percentage and PF in different succession phases of subalpine dark coniferous forest in Gongga Mountain. The results showed that: (1) In the same PF value, the moisture percentage in humus horizon increased gradually with the devel-opment of the succession of the dark coniferous forest; The moisture percentage of over-mature forest was the highest and>mature forest>half-mature forest>young growth forest; (2) With the increase of soil depth, the soil bulk density increased and the moisture percentage decreased, but the difference in the percentage of moisture was not notable in different succession phases. (3) In different succession series, the vegetation affected the soil water characteristics by increasing the soil organic matter, improving the soil construction, receding the soil bulk density and enhancing the soil porosity; (4) The humus horizon of the dark coniferous forest soil has the highest water holding capability in this region. 展开更多
关键词 Gongga Mountain Moisture percentage PF value Dark coniferous forest Forest soil Water-holding capability
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Abiotic and biotic drivers of species diversity in understory layers of cold temperate coniferous forests in North China 被引量:10
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作者 Hui Wang Mengtao Zhang Hongwei Nan 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2213-2225,共13页
Understory plants are important components of forest ecosystems and play a crucial role in regulating community structures,function realization,and community succession.However,little is known about how abiotic and bi... Understory plants are important components of forest ecosystems and play a crucial role in regulating community structures,function realization,and community succession.However,little is known about how abiotic and biotic drivers affect the diversity of understory species in cold temperate coniferous forests in the semiarid climate region of North China.We hypothesized that(1)topographic factors are important environmental factors affecting the distribution and variation of understory strata,and(2)different understory strata respond differently to environmental factors;shrubs may be significantly affected by the overstory stratum,and herbs may be more affected by surface soil conditions.To test these hypotheses,we used the boosted regression tree method to analyze abiotic and biotic environmental factors that influence understory species diversity,using data from 280 subplots across 56 sites in cold temperate coniferous forests of North China.Elevation and slope aspect were the dominant and indirect abiotic drivers affecting understory species diversity,and individual tree size inequality(DBH variation)was the dominant biotic driver of understory species diversity;soil water content was the main edaphic factors affecting herb layers.Elevation,slope aspect,and DBH variation accounted for 36.4,14.5,and 12.1%,respectively,of shrub stratum diversity.Shrub diversity decreased with elevation within the range of altitude of this study,but increased with DBH variation;shrub diversity was highest on north-oriented slopes.The strongest factor affecting herb stratum species diversity was slope aspect,accounting for 25.9%of the diversity,followed by elevation(15.7%),slope(12.2%),and soil water content(10.3%).The highest herb diversity was found on southeast-oriented slopes and the lowest on northeast-oriented slopes;herb diversity decreased with elevation and soil water content,but increased with slope.The results of the study provide a reference for scientific management and biodiversity protection in cold temperate coniferous forests of North China. 展开更多
关键词 ABIOTIC and biotic DRIVERS Cold TEMPERATE coniferOUS forests North China SEMI-ARID region UNDERSTORY species diversity
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The Limiting Effect of Deep Soil Water on Evapotranspiration of a Subtropical Coniferous Plantation Subjected to Seasonal Drought 被引量:12
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作者 TANG Yakun WEN Xuefa +2 位作者 SUN Xiaomin ZHANG Xinyu WANG Huimin 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第2期385-395,共11页
Seasonal drought is a common occurrence in humid climates.The year 2003 was the driest year during the period 1985-2011 in southeastern China.The objective of this study was to elucidate the impact of the exceptional ... Seasonal drought is a common occurrence in humid climates.The year 2003 was the driest year during the period 1985-2011 in southeastern China.The objective of this study was to elucidate the impact of the exceptional drought in 2003,compared with eddy flux measurements during 2004-11,on the dynamics of evapotranspiration (ET) and related factors,as well as their underlying mechanisms,in a subtropical coniferous plantation in southeastern China.It was found that daily ET decreased from 5.34 to 1.84 mm during the intensive drought period and recovered to 4.80 mm during the subsquent recovering drought period.Path analysis indicated that ET was mainly determined by canopy conductance and deep soil water content (50 cm) during the intensive drought and recovering drought periods,respectively.The canopy conductance offset the positive effect of air vapor pressure deficit on ET when suffering drought stress,while the canopy conductance enhanced the positive effect of air temperature on ET during the late growing season.Because the fine roots of this plantation are mainly distributed in shallow soil,and the soil water in the upper 40 cm did not satisfy the demand for ET,stomatal closure and defoliation were evident as physiological responses to drought stress. 展开更多
关键词 CHINAFLUX EVAPOTRANSPIRATION seasonal drought subtropical coniferous plantation
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Contribution of Root Respiration to Total Soil Respiration in a Betula ermanii-Dark Coniferous Forest Ecotone of the Changbai Mountains, China 被引量:8
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作者 LIU Ying HAN Shi-Jie ZHOU Yu-Mei ZHANG Jun-Hui 《Pedosphere》 SCIE CAS CSCD 2005年第4期448-455,共8页
Total and root-severed soil respiration rates for five plots set up 50 m apart in a Betula ermanii Cham.-dark coniferous forest ecotone on a north-facing slope of the Changbai Mountains, China, were measured to evalua... Total and root-severed soil respiration rates for five plots set up 50 m apart in a Betula ermanii Cham.-dark coniferous forest ecotone on a north-facing slope of the Changbai Mountains, China, were measured to evaluate the seasonal variations of soil respiration, to assess the effect of soil temperature and water content on soil respiration, and to estimate the relative contributions of root respiration to the total soil respiration. PVC cylinders in each of 5 forest types of a B. ermanii-dark coniferous forest ecotone were used to measure soil respirations both inside and outside of the cylinders. The contribution of roots to the total soil respiration rates ranged from 12.5% to 54.6%. The mean contribution of roots for the different plots varied with the season, increasing from 32.5% on June 26 to 36.6% on August 3 and to 41.8% on October 14. In addition, there existed a significant (P < 0.01) logarithmic relationship between total soil respiration rate and soil temperature at 5 cm soil depth. Also, a similar trend was observed for the soil respiration and soil water content at the surface (0-5 cm) during the same period of time. 展开更多
关键词 Betula ermanii Cham. dark coniferous forest ECOTONE root respiration soil respiration
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Nutrient and Litter Patterns in Three Subalpine Coniferous Forests of Western Sichuan, China 被引量:6
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作者 LIN Bo LIU Qing +1 位作者 WU Yan HE Hai 《Pedosphere》 SCIE CAS CSCD 2006年第3期380-389,共10页
Investigations were conducted to quantify litterfall, and litter and nutrient accumulation in forest floor, and to acquire information on litter decomposition and nitrogen and phosphorus release patterns in three diff... Investigations were conducted to quantify litterfall, and litter and nutrient accumulation in forest floor, and to acquire information on litter decomposition and nitrogen and phosphorus release patterns in three different subalpine coniferous forests, a plantation (P1), a secondary forest (SF), and a primitive forest (PF), in western Sichuan, China. The litter trap method was used to evaluate litterfall with the litterbag method being utilized for litter decomposition. Seasonal patterns of litterfall were similar in the three forests, with two peaks occurring in September-November and March-May. The plantation revealed an annual litterfall of 4.38 x 103 kg ha-1, which was similar to those of SF and PF, but P1 had a lower mass loss rate and a higher C/N ratio. The C/N ratio may be a sound predictor for the decomposition differences. N concentrations of leaf litter in both the secondary forest and primitive forest increased first and then decreased, and the percentages of their final/initial values were 108.9% and 99.9%, respectively. P concentration in the three forests increased by the end of the study. The results of litterfall and decomposition indicated that in the plantation the potential to provide nutrients for soil organic matter was similar to those of SF and PF; however, its slower decomposition rate could result in a somewhat transient accumulation of litter in the forest floor. 展开更多
关键词 ACCUMULATION decomposition LITTERFALL nutrient release subalpine coniferous forests
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Soil Properties in Coniferous Forest Stands Along a Fly Ash Deposition Gradient in Eastern Germany 被引量:5
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作者 S. KLOSE F. MAKESCHIN 《Pedosphere》 SCIE CAS CSCD 2005年第6期681-694,共14页
Physical, chemical, and microbial properties of forest soils subjected to long-term fly ash depositions were analyzed in spruce (Picea abies (L.) Karst.) stands of eastern Germany on three forest sites along an emissi... Physical, chemical, and microbial properties of forest soils subjected to long-term fly ash depositions were analyzed in spruce (Picea abies (L.) Karst.) stands of eastern Germany on three forest sites along an emission gradient of 3 (high input), 6, and 15 km (low input) downwind of a coal-fired power plant. Past emissions resulted in an atypical high mass of mineral fly ash constituents in the organic horizons at the high input site of 128 t ha-1 compared to 58 t ha-1 at the low input site. Magnetic susceptibility measurements proved that the high mineral content of the forest floor was a result of fly ash accumulation in these forest stands. Fly ash deposition in the organic horizons at Site I versus III significantly increased the pH values, effective cation exchange capacity, base saturation and, with exception of the L horizon, concentrations of mobile heavy metals Cd, Cr, and Ni, while stocks of organic C generally decreased. A principal component analysis showed that organic C content and base status mainly controlled soil microbial biomass and microbial respiration rates at these sites, while pH and mobile fractions of Cd, Cr, and Ni governed enzyme activities. Additionally, it was hypothesized that long-term fly ash emissions would eventually destabilize forest ecosystems. Therefore, the results of this study could become a useful tool for risk assessment in forest ecosystems that were subjected to past emissions from coal-fired power plants. 展开更多
关键词 coniferous forests fly ash deposition magnetic susceptibility microbial biomass mobile heavy metal fraction
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Carbon and Nitrogen Transformations in Surface Soils Under Ermans Birch and Dark Coniferous Forests 被引量:5
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作者 DENG Xiao-Wen HAN Shi-Jie +1 位作者 HU Yan-Ling ZHOU Yu-Mei 《Pedosphere》 SCIE CAS CSCD 2009年第2期230-237,共8页
Soil samples were taken from an Ermans birch (Betula ermanii)-dark coniferous forest (Picea jezoensis and Abies nephrolepis) ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northe... Soil samples were taken from an Ermans birch (Betula ermanii)-dark coniferous forest (Picea jezoensis and Abies nephrolepis) ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China, to compare soil carbon (C) and nitrogen (N) transformations in the two forests. The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy. Soil samples were incubated aerobically at 20℃ and field capacity of 700 g kg^-1 over a period of 27 weeks. The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest (P 〈 0.05), whereas the cumulative C mineralization (as CO2 emission) in the dark coniferous forest exceeded that in the Ermans birch (P 〈 0.05). Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest (P 〈 0.05). The results suggested that differences of forest types could result in considerable change in soil C and N transformations. 展开更多
关键词 dissolved organic C dissolved organic N Ermans birch-dark coniferous forest soil C transformation soil N transformation
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Active organic carbon pool of coniferous and broad-leaved forest soils in the mountainous areas of Beijing 被引量:4
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作者 GENG Yu-qing YU Xin-xiao +2 位作者 YUE Yong-jie LI Jin-hai ZHANG Guo-zhen 《Forestry Studies in China》 CAS 2009年第4期225-230,共6页
In order to explore the effects of different forest types on active soil carbon pool, the amounts and density of soil organic carbon (SOC) were studied at different soil horizons under typical coniferous and broad-l... In order to explore the effects of different forest types on active soil carbon pool, the amounts and density of soil organic carbon (SOC) were studied at different soil horizons under typical coniferous and broad-leaved forests in the mountainous area of Beijing. The results showed that the amount of total SOC, readily oxidizable carbon and particulate organic carbon decreased with increasing depths of soil horizons and the amounts at depths of 0-10 cm and 10-20 cm in broad-leaved forest was clearly higher than that in coniferous forests. The trend of a decrease in SOC density with increasing depth of the soil horizon was similar to that of the amount of SOC. However, no regular trend was found for SOC density at different depths between coniferous forest and broad-leaved forests. The ratio of readily oxidizable carbon to total amount of SOC ranged from 0.36-0.45 and the ratio of particulate organic carbon to total amount of SOC from 0.28-0.73; the ratios decreased with increasing depths of soil horizons. Active SOC was significantly correlated with total SOC; the relationship between readily oxidizable carbon and particulate organic carbon was significant. A broad-leaved forest may produce more SOC than a coniferous forest. 展开更多
关键词 coniferous forest broad-leaved forest readily oxidizable carbon particulate organic carbon soil organic carbon density
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Warming hiatus-and evergreen conifers in Altay-Sayan Region,Siberia 被引量:2
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作者 Viacheslav I.KHARUK Sergei T.IM Il'ya A.PETROV 《Journal of Mountain Science》 SCIE CSCD 2018年第12期2579-2589,共11页
"Warming hiatus" occurred in the AltaySayan Mountain Region, Siberia in c. 1997–2014. We analyzed evergreen conifer(EGC) stands area(satellite data) and trees(Siberian pine, Pinus sibirica Du Tour, Siberian... "Warming hiatus" occurred in the AltaySayan Mountain Region, Siberia in c. 1997–2014. We analyzed evergreen conifer(EGC) stands area(satellite data) and trees(Siberian pine, Pinus sibirica Du Tour, Siberian fir, Abies sibirica Ledeb.) growth increment(dendrochronology data) response to climate variables before and during the hiatus. During the hiatus, EGC area increased in the highlands(>1000 m)(+30%), whereas at low and middle elevations(<1000 m. a.s.l.) the EGC area decreased(-7%). The EGC area increase was observed on the rain-ward northwest slopes mainly. In highlands, EGC area increase mainly correlated with summer air temperature, whereas at low and middle elevations EGC area decrease correlated with drought index SPEI and vapor pressure deficit(VPD). EGC mortality(fir and Siberian pine) in lowland was caused by the synergy of water stress(inciting factor) and barkbeetle attacks(contributing factor). Tree growth increment(GI) dynamics differs with respect to elevation. At high elevation(1700 m) GI permanently increased since warming onset, whereas at the middle(900 m) and low elevations(450 m) GI increased until c. 1983 yr. with followed depression. That GI "breakpoint" occurred about a decade before hiatus onset. In spite of growth depression, during hiatus GI was higher than that in pre-warming period. At high elevation, GI positively responded to elevated June temperatures and negatively to moisture increase(precipitation, root zone moisture content, VPD, and SPEI). At low elevation GI negatively responded to June temperatures and positively to moisture increase. For both, low and high elevation, these patterns persisted throughout the study period(1967–2014). On the contrary, at middle elevations GI dependence on climate variables switch after breakpoint year(1983). Before breakpoint, June air temperature(positive correlation) and moisture(negative correlations) controlled GI. Further temperature increase leads GI depression and switched correlation signs to opposite(from positive to negative with temperature, and from negative to positive with moisture variables). 展开更多
关键词 GROWTH increment WARMING HIATUS WARMING impact conifer decline TREE GROWTH TREE MORTALITY conifer MORTALITY Water stress
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Effect of thinning intensity on understory herbaceous diversity and biomass in mixed coniferous and broad-leaved forests of Changbai Mountain 被引量:3
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作者 Gerong Wang Yue Sun +6 位作者 Mo Zhou Naiqian Guan Yuwen Wang Runhua Jiang Zhiyu Liu Mengjia Wu Fucai Xia 《Forest Ecosystems》 SCIE CSCD 2021年第4期713-725,共13页
Background:Herbs are an important part of the forest ecosystem,and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances.Based on the near-mature secondary coniferous... Background:Herbs are an important part of the forest ecosystem,and their diversity and biomass can reflect the restoration of vegetation after forest thinning disturbances.Based on the near-mature secondary coniferous and broad-leaved mixed forest in Jilin Province Forestry Experimental Zone,this study analyzed seasonal changes of species diversity and biomass of the understory herb layer after different intensities of thinning.Results:The results showed that although the composition of herbaceous species and the ranking of importance values were affected by thinning intensity,they were mainly determined by seasonal changes.Across the entire growing season,the species with the highest importance values in thinning treatments included Carex pilosa,Aegopodium alpestre,Meehania urticifolia,and Filipendula palmata,which dominated the herb layer of the coniferous and broad-leaved mixed forest.The number of species,Margalef index,Shannon-Wiener index and Simpson index all had their highest values in May,and gradually decreased with months.Pielou index was roughly inverted“N”throughout the growing season.Thinning did not increase the species diversity.Thinning can promote the total biomass,above-and below-ground biomass.The number of plants per unit area and coverage were related to the total biomass,above-and below-ground biomass.The average height had a significantly positive correlation with herb biomass in May but not in July.However,it exerted a significantly negative correlation with herb biomass in September.The biomass in the same month increased with increasing thinning intensity.Total herb biomass,above-and below-ground biomass showed positive correlations with Shannon-Winner index,Simpson index and Pielou evenness index in May.Conclusions:Thinning mainly changed the light environment in the forest,which would improve the plant diversity and biomass of herb layer in a short time.And different thinning intensity had different effects on the diversity of understory herb layer.The findings provide theoretical basis and reference for reasonable thinning and tending in coniferous and broad-leaved mixed forests. 展开更多
关键词 Selective thinning Mixed coniferous and broad-leaved forests Herbaceous plants DIVERSITY BIOMASS
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Impacts of Coriaria nepalensis colonization on vegetation structure and regeneration dynamics in a mixed conifer forest of Indian Central Himalaya 被引量:1
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作者 Nidhi Rani Mourya Kiran Bargali Surendra Singh Bargali 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期305-317,共13页
This study evaluated impacts of Coriaria nepalensis Wall.colonization on soil characteristics,vegetation structure and composition,regeneration status and expected future compositional changes,biomass and carbon stock... This study evaluated impacts of Coriaria nepalensis Wall.colonization on soil characteristics,vegetation structure and composition,regeneration status and expected future compositional changes,biomass and carbon stock in tree species of a mixed conifer forest of Central Himalaya.Three sites(1 ha each in an old landslide area)differing in Coriaria density(low:20 individuals ha^(-1);medium:120 indiv.ha^(-1);high:190 indiv.ha^(-1))were used to enumerate the tree species.A total of 9 tree species and 2830 individuals were recorded from the three study sites that represented a gradient of Coriaria density.Number of species varied from 3 to 7 and the individuals from 690 to 1270 per site with lowest numbers at low Coriaria density and highest at medium Coriaria density.The number of seedlings increased with increasing Coriaria density,and the sites were unique in their seedling composition,indicating marked temporal dynamics.Site wise regeneration analysis showed that regeneration was poor at the site with low Coriaria density and good at the high-density site where many species emerged as seedlings.These results indicate that the ameliorative effects of Coriaria in terms of soil buildup,and accumulation of nutrients and organic matter helped more species to colonize the area.This facilitative ability of Coriaria can be used to restore degraded forest ecosystems of Indian Central Himalaya. 展开更多
关键词 BASAL area conifer Coriaria Density FACILITATION Species richness
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A Study of Collecting Robot of Conifer Cone 被引量:1
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作者 陆怀民 于遵波 +2 位作者 刘晋浩 葛安华 杨丽萍 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第2期125-126,共2页
The collecting robot of conifer cone mainly consists of walking mechanism and manipulator. Manipulator has 5 freedoms. The main technical parameters of this robot are as follows :maximum height of collecting is 14m, m... The collecting robot of conifer cone mainly consists of walking mechanism and manipulator. Manipulator has 5 freedoms. The main technical parameters of this robot are as follows :maximum height of collecting is 14m, maximum radius of collecting is 68m, velocity of collecting is 0.65 m/s, and the maximum force of collecing is 2500N. 展开更多
关键词 conifer CONE SEED COLLECTING ROBOT
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Distribution and variability of n-alkanes in waxes of conifers 被引量:1
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作者 Mohamad Hassanzadeh-Khayyat Maryam Akaberi +2 位作者 Hamideh Moalemzadeh Haghighi Amirhossein Sahebkar Seyed Ahmad Emami 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第2期429-433,共5页
Epicuticular waxes have vital roles in the growth and development of plants and in defense. Conifers have a considerable amount of waxes on their cones and leaves.Here we characterized the n-alkane composition of Iran... Epicuticular waxes have vital roles in the growth and development of plants and in defense. Conifers have a considerable amount of waxes on their cones and leaves.Here we characterized the n-alkane composition of Iranian conifers, including Juniperus oblonga, J. foetidissima, J.sabina, J. communis subsp. hemisphaerica, J. excelsa,Cupressus sempervirens, Platycladus orientalis from Cupressaceae and Taxus baccata from Taxaceae for the first time using GC-FID analyses. In the waxes, 25 n-alkane homologs with chain lengths ranging from C7 to C32 were identified. Short-chain n-alkanes were dominant in almost all samples with some exceptions. Complementary studies to elucidate complete wax constituents of Iranian conifers and n-alkane distribution pattern as a function of geographical and bioclimatic variables are recommended. 展开更多
关键词 GYMNOSPERMS IRANIAN coniferS Epicuticular waxes CUPRESSACEAE TAXACEAE
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Conifer genetic engineering: Particle bombardment and Agrobacterium-mediated gene transfer and its application in future forests 被引量:1
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作者 唐巍 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期220-228,276,共10页
Many important advances in forest biotechnology have been made. The use of genetic transformation and the ap-plications of transgenic trees in modern forestry is now an important field. Two basic methodologies particl... Many important advances in forest biotechnology have been made. The use of genetic transformation and the ap-plications of transgenic trees in modern forestry is now an important field. Two basic methodologies particle bombardment and Agrobacterium-mediated transformation have been used on conifers. However, routine procedures exist for only a limited number of conifers. As a result only a few species have been successfully transformed into stable transgenic plants. The use of a particle bombardment has been more successful and transgenic plants have been produced in Picea abies, Picea glauca, Picea mariana, and Pinus radiata, although the level of production of stable transgenic plants is lower than that of Agrobacte-rium. At present, breeding programs have been directed toward improving bole shape, growth rate, wood properties, and quality, as well as toward improving root and shoot performance, pest resistance, stress tolerance, herbicide resistance, and ability to resist stresses, which will drive forestry to enter a new era of productivity and quality. This article provides a brief overview of the current state of knowledge on genetic transformation in conifers. 展开更多
关键词 Genetic engineering Particle bombardment AGROBACTERIUM conifer
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Species Diversity Based on Vertical Structure as Indicators of Artificial Restoration for Coniferous Forests in Southwest China 被引量:1
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作者 ZHANG Qiaoying ZHANG Yunchun +3 位作者 Eshetu Yirdaw LUO Peng YI Shaoliang Wu Ning 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期1003-1008,共6页
Five indices of species richness, species diversity and species evenness were used to assess a diversity of four types of coniferous forests undergone different artificial regeneration time. The study was based on the... Five indices of species richness, species diversity and species evenness were used to assess a diversity of four types of coniferous forests undergone different artificial regeneration time. The study was based on the vertical structure of forests, involving growth-forms of total plants as well as vertical layers of woody plants. The results showed that, except for the fourth layer of woody plants, the vertical structure of the four forests exhibited significant difference in terms of their species richness, species diversity and species evenness, suggesting that a species diversity index provided more detailed information and was a better index reflecting the regeneration processes in this region. It was recommended that silvicultural management of artificially regenerated forests should be strengthened to conserve the biodiversity of the forests, optimize forest structure and, in the long run, promote sustainable development of forest ecosystems. 展开更多
关键词 species richness species diversity species evenness forest management sub-alpine coniferous forests
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Vegetation-environment relationship in conifer dominating forests of the mountainous range of Indus Kohistan in northern Pakistan 被引量:1
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作者 Adam KHAN Moinuddin AHMED +6 位作者 Muhammad Faheem SIDDIQI Mohib SHAH Eduardo Soares CALIXTO Afsheen KHAN Paras SHAH Javed IQBAL Muhammad AZEEM 《Journal of Mountain Science》 SCIE CSCD 2020年第8期1989-2000,共12页
Environmental variables play a crucial role in shaping vegetation structure,mainly in mountainous ecosystems.Different studies have attempted to identify the environment-vegetation relationship of Conifer Dominating F... Environmental variables play a crucial role in shaping vegetation structure,mainly in mountainous ecosystems.Different studies have attempted to identify the environment-vegetation relationship of Conifer Dominating Forests(CDF)worldwide.However,due to differences in local climate and soil composition,different environmental drivers can be found.By applying multivariate analysis techniques,this study investigated the vegetation-environment relationship of CDF of Indus Kohistan in northern Pakistan.Our results showed that CDF of Indus Kohistan are distributed in five distinct ecological groups,which are dominated by different trees and understory species.A total of 7 trees and 71 understory species were recorded from the sampling sites.Cedrus deodara was the leading species among four groups,having the highest importance value(IV),density and basal area.Group I was dominated by Pinus wallichiana with the second highest importance value,density and basal area.In addition,elevation,slope,maximum water holding capacity(MWHC),soil moisture(SM),total organic matter(TOM),sodium,phosphorus and nickel showed highly significant influence on composition and distribution pattern of Indus Kohistan vegetation.Therefore,this study shows a new evidence of vegetation-environment relationship,pointing out specific drivers of vegetation structure in CDF of Indus Kohistan region in northern Pakistan. 展开更多
关键词 conifer forests Understory species Environmental variables Multivariate analysis Indus Kohistan Northern Pakistan
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How do nitrogen-limited alpine coniferous forests acquire nitrogen?A rhizosphere perspective 被引量:1
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作者 Huajun Yin Bartosz Adamczyk +5 位作者 Qitong Wang Biao Zhu Wanji Guo Xiaomin Zhu Qing Liu Ziliang Zhang 《Forest Ecosystems》 SCIE CSCD 2022年第6期745-754,共10页
Background:Alpine coniferous forest ecosystems dominated by ectomycorrhizal(ECM)tree species are generally characterized by low soil nitrogen(N)availability but stabilized plant productivity.Thus,elucidating potential... Background:Alpine coniferous forest ecosystems dominated by ectomycorrhizal(ECM)tree species are generally characterized by low soil nitrogen(N)availability but stabilized plant productivity.Thus,elucidating potential mechanisms by which plants maintain efficient N acquisition is crucial for formulating optimized management practices in these ecosystems.Methods:We summarize empirical studies conducted at a long-term field monitoring station in the alpine coniferous forests on the eastern Tibetan Plateau,China.We propose a root-soil interaction-based framework encompassing key components including soil N supply,microbial N transformation,and root N uptake in the rhizosphere.Results:We highlight that,(i)a considerable size of soil dissolved organic N pool mitigates plant dependence on inorganic N supply;(ii)ectomycorrhizal roots regulate soil N transformations through both rhizosphere and hyphosphere effects,providing a driving force for scavenging soil N;(iii)a complementary pattern of plant uptake of different soil N forms via root-and mycorrhizal mycelium-pathways enables efficient N acquisitions in response to changing soil N availability.Conclusions:Multiple rhizosphere processes abovementioned collaboratively contribute to efficient plant N acquisition in alpine coniferous forests.Finally,we identify several research outlooks and directions to improve the understanding and prediction of ecosystem functions in alpine coniferous forests under on-going global changes. 展开更多
关键词 Plant nitrogen acquisition Root-soil interaction Alpine coniferous forests Nitrogen limitation RHIZOSPHERE
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Responses of soil Collembolans to vegetation restoration in temperate coniferous and broad-leaved mixed forests 被引量:1
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作者 Chen Ma Xiuqin Yin +1 位作者 Huan Xu Yan Tao 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2333-2345,共13页
A total of 900 soil samples were collected from five habitats,including primary coniferous broad-leaved mixed forests,secondary coniferous broad-leaved mixed forests,secondary broad-leaved forests,secondary shrub fore... A total of 900 soil samples were collected from five habitats,including primary coniferous broad-leaved mixed forests,secondary coniferous broad-leaved mixed forests,secondary broad-leaved forests,secondary shrub forests,and cutover lands in spring,summer,and autumn to quantify responses of soil Collembolans(springtails)to the restoration of vegetation of temperate coniferous and broad-leaved mixed forests.The results reveal that the taxonomic composition of Collembolans varied in the different stages of vegetation restoration.Seasonal variations were in regard to their abundance and richness.High similarities existed in Collembola communities at different stages of vegetation restoration,and distribution patterns of Collembola taxa displayed an evenness throughout all habitats.Soil Collembolans tended to gather on litter layers and soil surface;the highest abundance was found in the upper 5 cm soil layer during the initial stages of vegetation recovery.Tomocerus,Proisotoma,and Folsomia genera responded positively to the restoration of vegetation.However,responses of Ceratophysella and Parisotoma genera were negative.In addition,the Onychiuridae family did not respond to the vegetation restoration process.It was concluded that restoration of vegetative cover can increase the abundance of soil Collembolans,but different genera respond differently. 展开更多
关键词 Soil Collembolans(springtails) Temperate coniferous and broad-leaved mixed forests Vegetation restoration
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