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Floristic diversity and composition of the Biteyu forest in the Gurage mountain chain(Ethiopia):implications for forest conservation 预览
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作者 Talemos Seta Sebsebe Demissew Zerihun Woldu 《林业研究:英文版》 CAS CSCD 2019年第1期319-335,共17页
The Afromontane forests of Ethiopia have been under a serious degradation threat.Assessment of floristic diversity and species composition in Biteyu forest of Gurage mountain chain in the central Ethiopia was conducte... The Afromontane forests of Ethiopia have been under a serious degradation threat.Assessment of floristic diversity and species composition in Biteyu forest of Gurage mountain chain in the central Ethiopia was conducted to examine the pattern of forest structure.Thirty plots of 30 m×30 m were used to record the vegetation and environmental data using systematic sampling technique.The local name,plant scientific names,DBH,height,species abundance and percentage canopy cover of plant species were recorded.Shannon diversity index and Sorensen’s coefficients was used for comparison among communities and similar forests in the country.Threats to the forest biodiversity in Biteyu were determined by counting cattle interference and wood stumps as disturbance indicators.Relative Euclidean Distance measures by using Ward’s method(linkage)was applied for cluster analysis.Environmental variables were also recorded in each plot.Woody species population structure,basal area and importance value index were analyzed using spreadsheet programs.Data on species distribution and environmental variables in the forest were analyzed by canonical correspondence analysis.A total of 190 species in 154 genera under 73 families were identified.Twenty species were found to be endemic taxa to the Flora Area.Only three plant community types were identified from the cluster analysis due to the high human influence.The Sorensen’s coefficient showed the resemblance of the Biteyu forest with other Dry Evergreen Afromontane forests in the country.Moreover,altitude and slope strongly affect the species composition and structure of Biteyu forest.Given the high anthropogenic influence,high endemism,high dependence of the local community on the forest resources,forest conservation and restoration measures should be done by stakeholders. 展开更多
关键词 Biteyu FOREST FOREST CONSERVATION FOREST structure Plant COMMUNITY Threats
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Post-fire soil nutrient dynamics in a tropical dry deciduous forest of Western Ghats,India 预览
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作者 Satyam Verma Dharmatma Singh +1 位作者 Ajeet Kumar Singh Shanmuganathan Jayakumar 《森林生态系统:英文版》 CSCD 2019年第1期67-75,共9页
Background: The effect of forest fire on soil is complex and relatively less understood than its above ground effect.Understanding the effect of fire on forest soils can allow improving management of valuable forest e... Background: The effect of forest fire on soil is complex and relatively less understood than its above ground effect.Understanding the effect of fire on forest soils can allow improving management of valuable forest ecosystems as adequate and proper information is very important for efficient management. We have studied the recovery of soil properties after fire, using a chronosequence approach(two, five and fifteen years after fire and control). Soil samples were collected from each plot of four fire patches(B0, B2, B5 & B15) from three different depths viz. 0–10(Top), 10–20(Middle), and 20–30 cm(Bottom).Results: Soil organic carbon was lower than unburned plots after the fire and could not recover to the level of unburned plot(B0) even in 15 years. Total N, available P, and extractable K were lower 2-years and 5-years after the fire but are higher than unburned plot after 15-years. Available nitrogen(NO3^- and NH4^+) remain unchanged or higher than B0 in burned patches. Soil pH, Bulk Density, Water Holding Capacity, and Electrical Conductivity was lower initially after the fire. Forest fires have affected soil properties considerably. The response of soil properties varied with years after fire and soil depth.Conclusion: Forest fires occur very frequently in the study area. Significant quantities of carbon and total nitrogen are lost to the atmosphere by burning of litter, duff, and soil OM. Because nitrogen is one of the most important soil nutrients, the recapture of N lost by volatilization during a fire must receive special attention. Long-term studies are required to better understand the recovery of soil nitrogen. 展开更多
关键词 Soil properties Western Ghats TROPICAL DRY DECIDUOUS FOREST FOREST fire FOREST SOILS
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Analysis of PM2.5 concentrations in Heilongjiang Province associated with forest cover and other factors 预览
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作者 Yu Zheng San Li +2 位作者 Chuanshan Zou Xiaojian Ma Guocai Zhang 《林业研究:英文版》 CAS CSCD 2019年第1期269-276,共8页
Atmospheric particulate matter(PM2.5)seriously influences air quality.It is considered one of the main environmental triggers for lung and heart diseases.Air pollutants can be adsorbed by forest.In this study we inves... Atmospheric particulate matter(PM2.5)seriously influences air quality.It is considered one of the main environmental triggers for lung and heart diseases.Air pollutants can be adsorbed by forest.In this study we investigated the effect of forest cover on urban PM2.5 concentrations in 12 cities in Heilongjiang Province,China.The forest cover in each city was constant throughout the study period.The average daily concentration of PM2.5 in 12 cities was below 75 lg/m3 during the non-heating period but exceeded this level during heating period.Furthermore,there were more moderate pollution days in six cities.This indicated that forests had the ability to reduce the concentration of PM2.5 but the main cause of air pollution was excessive human interference and artificial heating in winter.We classified the 12 cities according to the average PM2.5 concentrations.The relationship between PM2.5 concentrations and forest cover was obtained by integrating forest cover,land area,heated areas and number of vehicles in cities.Finally,considering the complexity of PM2.5 formation and based on the theory of random forestry,we selected six cities and analyzed their meteorological and air pollutant data.The main factors affecting PM2.5 concentrations were PM10,NO2,CO and SO2 in air pollutants while meteorological factors were secondary. 展开更多
关键词 FOREST COVER Heilongjiang PROVINCE Influencing factor PM2.5 CONCENTRATIONS RANDOM FOREST
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Comparative study of the stoichiometric characteristics of karst and non-karst forests in Guizhou, China 预览
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作者 Yabing Zhang Chuanyan Zhou +6 位作者 Wenqiang Lv Lihua Dai Jingang Tang Shaoqi Zhou Lihua Huang Anding Li Jianli Zhang 《林业研究:英文版》 CAS CSCD 2019年第3期799-806,共8页
Carbon (C), nitrogen (N), and phosphorous (P) levels and their stoichiometry in plant components (leaves, branch trunks, roots) of trees in a karst forest and non-karst forest are compared. The results show that the C... Carbon (C), nitrogen (N), and phosphorous (P) levels and their stoichiometry in plant components (leaves, branch trunks, roots) of trees in a karst forest and non-karst forest are compared. The results show that the C contents, C:N and C:P ratios of dominant species in the karst forest were lower than those in the non-karst forest, but the N and P and the N:P ratio were higher;C:N:P ratios in plant organs of trees in the karst forest were in the order of trunks>roots>branches>leaves. However, C:N:P ratio in the non-karst forest trees were trunks>branches>roots>leaves. Moreover, ratio of C:N:P in trunks was highest and lowest in leaves in both forests. In non-karst forest trees, N:P was in the order of leaves> roots>branches>trunks. There were no significant differences in the ratio of N:P in different plant components of trees in the karst forest. However, in karst and non-karst forest trees, the ratio of N:P in leaves was highest;positive correlations between N and P contents, and N and N:P ratios were observed in both karst and non-karst forests (p<0.001). Negative correlations between P and N:P ratios (p<0.05) were observed in karst forest trees, while positive correlations were observed in non-karst forest trees. 展开更多
关键词 KARST FOREST Non-karst FOREST STOICHIOMETRIC CHARACTERISTICS Plant organs
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森林都市主义:比利时索尼安森林的城市-生态策略及实施途径
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作者 布鲁诺·德·缪德尔 凯利·香农 +1 位作者 阮明匡 田乐(译) 《景观设计学》 CSCD 2019年第1期18-33,共16页
本文通过回顾大布鲁塞尔及周边地区的索尼安森林与人居环境交融演变的发展历程,阐释了'森林都市主义'这一概念。森林景观被认为是生态(提供大量生态系统服务)和城市环境的基本结构。森林都市主义是城市建设的一种形式,其依靠森... 本文通过回顾大布鲁塞尔及周边地区的索尼安森林与人居环境交融演变的发展历程,阐释了'森林都市主义'这一概念。森林景观被认为是生态(提供大量生态系统服务)和城市环境的基本结构。森林都市主义是城市建设的一种形式,其依靠森林作为跨越(与交通、人居环境和生态相关的)尺度和维度的结构性要素。城市建设与大面积森林的相互作用体现为地域尺度上具有不同性质的各式森林形态。本文揭示了布鲁塞尔地区的森林和城市建设之间的相互影响,其中,城市环境的尺度、密度、品质和发展压力不尽相同,从坐落于森林中的人类定居点到拥有鲜明肌理的森林-城市的形式和方式也有所差异。索尼安森林及其周围环境随着时间发生的持续变化、所面临的当代挑战,以及未来可能的发展方向都非常引人瞩目。本文探究了森林砍伐与造林、人居环境与城市环境重建之间平行却又相互交织的过程和复杂关系。最后,作者认为,当下迫切需要通过重新梳理开发与保护的关系,来重建城市与森林之间生产与消耗的平衡。 展开更多
关键词 森林 都市主义 比利时 设计研究 索尼安森林
Influencing factors and growth state classification of a natural Metasequoia population 预览
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作者 Mu Liu Zhongke Feng +1 位作者 Chenghui Ma Liyan Yang 《林业研究:英文版》 CAS CSCD 2019年第1期337-345,共9页
By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms,a new method is proposed that is suitable for classifying the growth state of a natu... By analyzing the importance of influencing factors and conducting a comparative study of the effects of different sorting algorithms,a new method is proposed that is suitable for classifying the growth state of a natural Metasequoia glyptostroboides Hu and W.C.Cheng population.We studied 2817 M.glyptostroboides trees over 100 years old and analyzed their growth state by measuring 15 factors from stumpage,site condition,and environmental data.The dimensionality of all factors were reduced using the random forest algorithm,and we classified the remaining factors using the following algorithms:random forest,back-propagation(BP)neural networks,and support vector machine(SVM).The applicability of each sorting algorithm was analyzed.When all the d factors are used for classification and modeling,the model’s overall accuracy,kappa coefficient and test accuracy were 85.5%,0.739 and 85.8%,respectively.By reducing the dimensionality of the factors using the random forest algorithm,11 factors most strongly influenced the classifications of the growth state of the Metasequoia population:diameter at breast height,height,crown width,age from stumpage data;longitude,latitude,elevation,slope aspect,gradient and slope position from the site condition data;and the edge of the field from the environmental data.For classifying the Metasequoia population,the random forest algorithm has the highest overall accuracy at 87.2%,which is 3.4 and 2.3%higher than the BP neural networks and SVM algorithms,respectively.The SVM algorithm is superior to the random forest algorithm with respect to classifying the state of mortality.The combination of the random forest and SVM algorithms and their combined information can be used to classify and predict the growth state of this natural M.glyptostroboides population to provide a scientific basis for its effective protection. 展开更多
关键词 METASEQUOIA glyptostroboides GROWTH state RANDOM FOREST Support VECTOR machine(SVM) Influencing factor
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Object-based forest gaps classification using airborne LiDAR data 预览
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作者 Xuegang Mao Jiyu Hou 《林业研究:英文版》 CAS CSCD 2019年第2期617-627,共11页
Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data.To study the segmentation and classification processes of object-based forest gaps classificati... Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data.To study the segmentation and classification processes of object-based forest gaps classification at a regional scale,we sampled a natural secondary forest in northeast China at Maoershan Experimental Forest Farm.Airborne light detection and ranging(LiDAR;3.7 points/m^2)data were collected as the original data source and the canopy height model(CHM)and topographic dataset were extracted from the LiDAR data.The accuracy of objectbased forest gaps classification depends on previous segmentation.Thus our first step was to define 10 different scale parameters in CHM image segmentation.After image segmentation,the machine learning classification method was used to classify three kinds of object classes,namely,forest gaps,tree canopies,and others.The common support vector machine(SVM)classifier with the radial basis function kernel(RBF)was first adopted to test the effect of classification features(vegetation height features and some typical topographic features)on forest gap classification.Then the different classifiers(KNN,Bayes,decision tree,and SVM with linear kernel)were further adopted to compare the effect of classifiers on machine learning forest gaps classification.Segmentation accuracy and classification accuracy were evaluated by using Moller’s method and confusion metrics,respectively.The scale parameter had a significant effect on object-based forest gap segmentation and classification.Classification accuracies at different scales revealed that there were two optimal scales(10 and 20)that provided similar accuracy,with the scale of 10 yielding slightly greater accuracy than 20.The accuracy of the classification by using combination of height features and SVM classifier with linear kernel was 91%at the optimal scale parameter of 10,and it was highest comparing with other classification classifiers,such as SVM RBF(90%),Decision Tree(90%),Bayes(90%),or KNN(87%).The classifiers had no sig 展开更多
关键词 FOREST gap Scale SEGMENTATION Classification FEATURE LIDAR CHM Object based Machine learning
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Biomass increment and mortality losses in tropical secondary forests of Hainan,China 预览
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作者 Junfu Zhao Chunsheng He +6 位作者 Chunlin Qi Xu Wang Haiyan Deng Chunxin Wang Haiwei Liu Lianyan Yang Zhenghong Tan 《林业研究:英文版》 CAS CSCD 2019年第2期647-655,共9页
Secondary forests,created after heavy logging,are an important part of China’s forests.We investigated forest biomass and its accumulation rate in 38 plots in a tropical secondary forest on Hainan Island.These second... Secondary forests,created after heavy logging,are an important part of China’s forests.We investigated forest biomass and its accumulation rate in 38 plots in a tropical secondary forest on Hainan Island.These secondary forests are moderate carbon sinks,averaging 1.96–2.17 t C ha^-1 a^-1.Biomass increment is largely by medium-sized(10–35 m)trees.Tree mortality accounts for almost 30%of the biomass and plays a negligible role in biomass accumulation estimates.Mortality rate is highly dependent on tree size.For small trees and seedlings,it is related to competition due to elevated irradiance after logging.Regarding prospective biomass and rates of accumulation,recovery is not as rapid as in secondary forests of cleared land.Therefore,tropical forests are susceptible to logging operations and need careful forest management. 展开更多
关键词 Tropical secondary forest management Carbon SINK Inventory Dynamic PLOT LOGGING
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Diurnal and seasonal variations in carbon fluxes in bamboo forests during the growing season in Zhejiang province,China 预览
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作者 Liang Chen Yuli Liu +5 位作者 Guomo Zhou Fangjie Mao Huaqiang Du Xiaojun Xu Pingheng Li Xuejian Li 《林业研究:英文版》 CAS CSCD 2019年第2期657-668,共12页
Bamboo forest is an important forest type in subtropical China and is characterized by fast growth and high carbon sequestration capacity.However,the dynamics of carbon fluxes during the fast growing period of bamboo ... Bamboo forest is an important forest type in subtropical China and is characterized by fast growth and high carbon sequestration capacity.However,the dynamics of carbon fluxes during the fast growing period of bamboo shoots and their correlation with environment factors are poorly understood.We measured carbon dioxide exchange and climate variables using open-path eddy covariance methods during the 2011 growing season in a Moso bamboo forest(MB,Phyllostchys edulis)and a Lei bamboo forest(LB,Phyllostachys violascens)in Zhejiang province,China.The bamboo forests were carbon sinks during the growing season.The minimum diurnal net ecosystem exchange(NEE)at MB and LB sites were-0.64 and-0.66 mg C m^-2 s^-1,respectively.The minimum monthly NEE,ecosystem respiration(RE),and gross ecosystem exchange(GEE)were-99.3±4.03,76.2±2.46,and-191.5±4.98 g C m-2 month-1,respectively,at MB site,compared with-31.8±3.44,70.4±1.41,and-157.9±4.86 g C m^-2 month^-1,respectively,at LB site.Maximum RE was 92.1±1.32 g C m^-2 month^-1 at MB site and 151.0±2.38 g C m^-2 month^-1 at LB site.Key control factors varied by month during the growing season,but across the whole growing season,NEE and GEE at both sites showed similar trends in sensitivities to photosynthetic active radiation and vapor pressure deficit,and air temperature had the strongest correlation with RE at both sites.Carbon fluxes at LB site were more sensitive to soil water content compared to those at MB site.Both onyear(years when many new shoots are produced)and offyear(years when none or few new shoots are produced)should be studied in bamboo forests to better understand their role in global carbon cycling. 展开更多
关键词 Bamboo forest EDDY COVARIANCE CARBON fluxes CARBON SEQUESTRATION
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Effects of Pheretima sp.and Eisenia foetida on Changes in Microbial Populations of Forest Soil in Different Seasons 预览
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作者 Yingsen HE Yang ZHAO Bing HE 《农业生物技术:英文版》 CAS 2019年第3期81-83,共3页
[Objectives]This study was conducted to investigate the effects of artificially cultured Eisenia foetida and wild earthworms ( Pheretima sp.) on the changes of microbial populations in forest soil in different seasons... [Objectives]This study was conducted to investigate the effects of artificially cultured Eisenia foetida and wild earthworms ( Pheretima sp.) on the changes of microbial populations in forest soil in different seasons.[Methods]Artificially cultured E.foetida and wild earthworms were introduced to forest soil,and changes in the number of microbial populations under earthworm-microbe interaction were investigated in different seasons by tracking observation.The effects of earthworm activities on the number of different microbial populations were discussed also.[Results]Different microbial populations all increased in the soil to different degrees after the introduction of earthworms.The effects of the wild earthworms on the changes in bacteria,actinomycetes and fungi in the soil were different from those of artificially cultivated earthworms to certain degrees.[Conclusions]This study provides a theoretical basis for organic agriculture that relies on the decomposition of organic matter to release nutrients. 展开更多
关键词 EARTHWORM Forest land MICROORGANISMS SEASON
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Environmental factors influencing snowfall and snowfall prediction in the Tianshan Mountains, Northwest China
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作者 ZHANG Xueting LI Xuemei +2 位作者 LI Lanhai ZHANG Shan QIN Qirui 《干旱区科学:英文版》 SCIE CSCD 2019年第1期15-28,共14页
Snowfall is one of the dominant water resources in the mountainous regions and is closely related to the development of the local ecosystem and economy. Snowfall predication plays a critical role in understanding hydr... Snowfall is one of the dominant water resources in the mountainous regions and is closely related to the development of the local ecosystem and economy. Snowfall predication plays a critical role in understanding hydrological processes and forecasting natural disasters in the Tianshan Mountains, where meteorological stations are limited. Based on climatic, geographical and topographic variables at 27 meteorological stations during the cold season(October to April) from 1980 to 2015 in the Tianshan Mountains located in Xinjiang of Northwest China, we explored the potential influence of these variables on snowfall and predicted snowfall using two methods: multiple linear regression(MLR) model(a conventional measuring method) and random forest(RF) model(a non-parametric and non-linear machine learning algorithm). We identified the primary influencing factors of snowfall by ranking the importance of eight selected predictor variables based on the relative contribution of each variable in the two models. Model simulations were compared using different performance indices and the results showed that the RF model performed better than the MLR model, with a much higher R~2 value(R~2=0.74;R~2, coefficient of determination) and a lower bias error(RSR=0.51;RSR, the ratio of root mean square error to standard deviation of observed dataset). This indicates that the non-linear trend is more applicable for explaining the relationship between the selected predictor variables and snowfall. Relative humidity, temperature and longitude were identified as three of the most important variables influencing snowfall and snowfall prediction in both models, while elevation, aspect and latitude were of secondary importance, followed by slope and wind speed. These results will be beneficial to understand hydrological modeling and improve management and prediction of water resources in the Tianshan Mountains. 展开更多
关键词 SNOWFALL PREDICTION SNOWFALL fraction random forest multiple linear regression PREDICTOR variables TIANSHAN Mountains
Soil Metagenome of Tropical White Sand Heath Forests in Borneo:What Functional Traits Are Associated with an Extreme Environment Within the Tropical Rainforest?
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作者 Dorsaf KERFAHI Binu M.TRIPATHI +6 位作者 Johan W.Ferry SLIK Rahayu S.SUKRI Salwana JAAFAR Ke DONG Matthew Chidozie OGWU Hyo-Ki KIM Jonathan M.ADAMS 《土壤圈:英文版》 SCIE CAS CSCD 2019年第1期12-23,共12页
White sand heath forests(WS) or kerangas, an unusual variant of tropical forests in Borneo, characterized by open scrubby vegetation, low productivity, and distinctive plant species composition and soil microbial comm... White sand heath forests(WS) or kerangas, an unusual variant of tropical forests in Borneo, characterized by open scrubby vegetation, low productivity, and distinctive plant species composition and soil microbial community, are regarded as a stressful lowpH and/or nutrient environment. We investigated whether the functional soil metagenome also shows a predicted set of indicators of stressful conditions in WS. Based on stress-tolerant strategies exhibited by larger organisms, we hypothesized that genes for stress tolerance, dormancy, sporulation, and nutrient processing are more abundant in the soil microbiota of WS. We also hypothesized that there is less evidence of biotic interaction in white sand soils, with lower connectivity and fewer genes related to organismic interactions. In Brunei, we sampled soils from a WS and a normal primary dipterocarp forest, together with an inland heath, an intermediate forest type. Soil DNA was extracted, and shotgun sequencing was performed using Illumina HiSeq platform, with classification by the Metagenomics Rapid Annotation using Subsystem Technology(MG-RAST). The results, on one hand, supported our hypothesis(on greater abundance of dormancy, virulence, and sporulation-related genes). However, some aspects of our results showed no significant difference(specifically in stress tolerance, antibiotic resistance, viruses, and clustered regularly interspaced short palindrome repeats(CRISPRs)). It appears that in certain respects, the extreme white sand environment produces the predicted strategy of less biotic interaction, but exhibits high soil microbiota connectivity and functional diversity. 展开更多
关键词 antibiotic resistance biotic interaction kerangas microbial community MICROBIOTA SHOTGUN METAGENOMICS stress tolerance TROPICAL forest
Carbon Storage and Distribution of the Mature Pinus massoniana Plantation in Northwest Guangxi 预览
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作者 Zhenge HUANG Minyang XIE +4 位作者 Mingbao WEI Bin HE Shaozhuang MO Gang ZHOU Ji LIANG 《农业生物技术:英文版》 CAS 2019年第3期141-144,共4页
[Objectives]This study was conducted to understand the carbon sequestration function of mature Pinus massoniana plantation in northwest Guangxi.[Methods]The carbon storage and distribution in a 26-year-old P.massonian... [Objectives]This study was conducted to understand the carbon sequestration function of mature Pinus massoniana plantation in northwest Guangxi.[Methods]The carbon storage and distribution in a 26-year-old P.massoniana plantation were investigated through biomass harvesting in Shankou Forestry Farm of Nandan County,Guangxi Province.[Results]The average carbon content of P.massoniana was 489.3 g/kg,and the carbon contents of different organs ranked from large to small as pine needles > trunks > trunk bark > roots > branches.The carbon contents of understory shrub layer,herb layer and litter layer were 453.0,425.6 and 482.5 g/kg,respectively.The soil organic carbon content in forestland varied from 6.20 to 32.15 g/kg,decreasing with the depth of the soil layer.The carbon storage of the mature P.massoniana plantation ecosystem was 232.13 t/hm^2,of which the tree layer,shrub layer,herb layer,litter layer and soil layer were 92.67,1.36,1.12 and 134.49 t/hm^2,respectively,which accounted for 39.92%,0.59%,0.48%,1.07% and 57.94% of the carbon storage of the whole ecosystem,respectively.The annual net productivity of the tree layer of the mature P.massoniana plantation was 10.36 t/(hm^2·a),the annual net carbon sequestration was 5.41 t/(hm^2·a),and the annual net CO2 absorption was 19.83 t/(hm^2·a).[Conclusions]This study provides basic data and scientific basis for rational evaluation of the ecological benefits of P.massoniana plantation in this area. 展开更多
关键词 PINUS massoniana MATURE FOREST CARBON CONTENT CARBON STORAGE
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基于森林清查资料的河南省森林植被碳储量动态变化 预览
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作者 刘领 王艳芳 +2 位作者 悦飞雪 李冬 赵威 《生态学报》 CAS CSCD 北大核心 2019年第3期864-873,共10页
利用1994-1998年、1999-2003年、2004-2008年、2009-2013年河南省4期森林资源清查数据,运用生物量转换因子连续函数法和平均生物量法,估算了1998-2013年河南省森林植被的碳储量和碳密度变化。研究结果表明,河南省森林植被碳储量由1998年... 利用1994-1998年、1999-2003年、2004-2008年、2009-2013年河南省4期森林资源清查数据,运用生物量转换因子连续函数法和平均生物量法,估算了1998-2013年河南省森林植被的碳储量和碳密度变化。研究结果表明,河南省森林植被碳储量由1998年的45.57 Tg增加到2013年的107.98 Tg,年均碳汇量为4.16 Tg/a。乔木林碳储量和碳密度分别由1998年的33.54 Tg和22.39 Mg/hm^2增加到2013年的97.11 Tg和31.80 Mg/hm^2。乔木林碳储量在所有植被类型中占主体,4个森林清查时期乔木林碳储量占森林植被总碳储量的比例分别为73.60%、79.22%、85.63%和89.93%。2013年森林清查时,乔木林中杨树和栎类碳储量最大,分别占总碳储量的37.61%和25.22%,各龄组乔木林碳密度大小顺序依次为成熟林>近熟林>中龄林>过熟林>幼龄林。阔叶林面积、碳储量、碳密度均高于针叶林,阔叶林是河南省森林碳汇的主要贡献者。人工林面积、碳储量、碳密度增加幅度都要高于天然林,人工林碳储量由1998年的9.62 Tg增加到2013年的55.67 Tg,占乔木林碳储量总增量的77.15%,人工林碳密度由1998年的17.86 Mg/hm^2提高到2013年的32.01 Mg/hm^2,人工林在河南省森林碳汇中逐步发挥重要的作用,逐渐成为河南省森林碳汇的主体,随着人工林生长为具有较高碳密度的成熟林,河南省乔木林将具有较大的碳汇潜力。 展开更多
关键词 森林 碳储量 碳密度 河南省
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朝阳县林业有害生物普查研究 预览
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作者 谭丽娟 《农业科技与装备》 2019年第3期16-17,22共3页
对朝阳县林业有害生物进行普查。介绍普查范围、普查对象、普查内容、普查方法及普查成果,分析外来入侵林业有害生物的影响,建立全县林业有害生物数据库,以期为朝阳县林业产业发展提供有力的支撑。
关键词 有害生物 普查 林业 朝阳县
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Conserving and restoring the Caicos pine forests: The first decade
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作者 Michele Dani Sanchez Bryan Naqqi Manco +2 位作者 Junel Blaise Marcella Corcoran Martin Allen Hamilton 《植物多样性:英文版》 CAS CSCD 2019年第2期75-83,共9页
The severe and rapid attack on the Caicos pine Pinus caribaea var. bahamensis (Pinaceae) by the nonnative invasive pine tortoise scale, Toumeyella parvicornis, has resulted in the death of most of the trees in the Tur... The severe and rapid attack on the Caicos pine Pinus caribaea var. bahamensis (Pinaceae) by the nonnative invasive pine tortoise scale, Toumeyella parvicornis, has resulted in the death of most of the trees in the Turks and Caicos Islands (TCI) in just over a decade. Local and international conservation efforts have enabled the necessary multi-disciplinary research, data gathering, and monitoring to develop and implement a restoration strategy for this endemic tree from the Bahaman archipelago. The native plant nu「sery established on North Caicos and horticultural expertise acquired throughout the years were crucial to the successful rescue of Caicos pine saplings from the wild populations and cultivation of new saplings grown from locally sourced seeds. These saplings have been used to establish six Restoration Trial Plots on Pine Cay and a seed orchard on North Caicos in TCI. Core Conservation Areas (CCAs) for the Caicos pine forests have been identified and mapped. Io date, forest within the Pine Cay CCA has been supplemented by planting more than 450 pine trees, which have survived at a high (>80%) rate. 展开更多
关键词 PINE forest restoration Plant NURSERY PINUS caribaea var. bahamensis Caribbean Conservation TURKS and Caicos ISLANDS
Species diversity in restoration plantings: Important factors for increasing the diversity of threatened tree species in the restoration of the Araucaria forest ecosystem
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作者 Taylor E. Shaw 《植物多样性:英文版》 CAS CSCD 2019年第2期84-93,共10页
The Araucaria forest ecosystem in southern Brazil is highly threatened: less than one percent of the original forest remains, and what is left is a fragmented agro-mosaic of mostly early-to-late secondary forest patch... The Araucaria forest ecosystem in southern Brazil is highly threatened: less than one percent of the original forest remains, and what is left is a fragmented agro-mosaic of mostly early-to-late secondary forest patches among high-yield agriculture and timber monocultures. Forest restoration initiatives in this region aim to restore degraded areas, however the limited number of species used in restoration projects represents a missed opportunity for species-rich plan tings. High diversity plantings represent a larger number of functional groups and provide a targeted conservation strategy for the high number of threatened species within this ecosystem. This study interviewed nurseries (Ns) and cultivated and planted, and what factors are driving the species selection process. An average of 20 species were reportedly used in restoration plantings, most of which are common, widespread species. Baseline data confirms that Ns and RPs have disproportionately low occurrences of threatened species in their inventories and plantings, supporting findings from previous research. Questionnaire responses reveal that opportunities for seed acquisition are an extremely important factor in order for nurseries to increase their diversity of cultivated species. Results also suggest that facilitating speciesrich plan tings for restoration practitioners would only be feasible if it did not increase the time required to complete planting projects, as it would minimize their ability to keep costs low. This study proposes solutions for increasing the number of species used in restoration practice-such as developing a comprehensive species list, fostering knowledge-sharing between actors, creating seed sharing programs, and in creasing coordination of planting projects. Long-term strategies inv olve complimenting traditional ex situ approaches with emerging inter-situ and quasi in situ conservation strategies which simultaneously provide long-term preservation of genetic diversity and increase seed production of target species. 展开更多
关键词 RESTORATION ARAUCARIA forest THREATENED species NURSERIES RESTORATION practitioners Decision-making
论战国中后期黄土高原东南地区的战争及其对森林的破坏 预览
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作者 吴长城 《农业考古》 2019年第1期147-150,共4页
黄土高原地区的森林破坏历来受到人们的关注。战国时期,尤其是到了中后期,这一地区战争的频次和规模达到了顶峰。连年的军事混战以及为维护战争需求而进行的兵器的生产、军事设施的修建、薪炭的采伐等对黄土高原东南地区的森林造成了前... 黄土高原地区的森林破坏历来受到人们的关注。战国时期,尤其是到了中后期,这一地区战争的频次和规模达到了顶峰。连年的军事混战以及为维护战争需求而进行的兵器的生产、军事设施的修建、薪炭的采伐等对黄土高原东南地区的森林造成了前所未有的破坏,黄土高原东南地区的原始森林首次出现有历史记载的遭大规模破坏的趋势。 展开更多
关键词 战国 黄土高原东南地区 战争 森林
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Forest carbon storage in Guizhou Province based on field measurement dataset
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作者 Chunzi Guo Yangyang Wu +1 位作者 Jian Ni Yinming GUO 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第1期8-21,共14页
Accurate estimation of forest carbon storage is crucial in understanding global and regional carbon cycles and projecting future ecological and economic scenarios.Guizhou is the largest karst landform province in Chin... Accurate estimation of forest carbon storage is crucial in understanding global and regional carbon cycles and projecting future ecological and economic scenarios.Guizhou is the largest karst landform province in China;61.9%of its land area is characterized as karst.However,monitoring its field biomass and carbon storage is difficult.This study synthesized and analyzed a comprehensive database of direct field observations of forest vegetation and soil carbon storage in Guizhou Province by using data from existing literature.The total vegetation carbon storage in Guizhou Province was 488.170 TgC,the average vegetation carbon density (VCD)was 27.866 MgC hm^-2,the total amount of soil organic carbon (SOC)(20 cm)was 1017.364 TgC,and the average SOC density was 58.074 MgC hm^-2.Among all vegetation types,needleleaf forest had the highest vegetation carbon stocks,and scrub presented the highest SOC storage.The vegetation and SOC storage values of the karst landform were 282.352 and 614.825 TgC,respectively,which were higher than those of the non-karst landform.VCD was concentrated at 10M0 MgC hm^-2,and SOC density was concentrated at 40-60,60-80,and 80-100 MgC hm^-2.This comprehensive regional data synthesis and analysis based on direct field measurement of vegetation and soil will improve our understanding of the forest carbon cycle in karst landforms under a changing climate. 展开更多
关键词 FOREST CARBON storage Field measurement DATASET KARST LANDFORM
基于统筹山水林田湖草系统治理思想方法的水环境治理建议--以广佛跨界水环境治理实践为例 预览
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作者 黄敏华 《节能与环保》 2019年第3期48-49,共2页
党的十九大报告提出了统筹山水林田湖草系统治理的生态文明建设路径,为在新的历史方位推进水污染防治工作指明了方向,本文遵循山水林田湖草生命共同体的思想理念,以佛山市广佛跨界水环境治理实践为例,分析广佛跨界河流污染整治面临的主... 党的十九大报告提出了统筹山水林田湖草系统治理的生态文明建设路径,为在新的历史方位推进水污染防治工作指明了方向,本文遵循山水林田湖草生命共同体的思想理念,以佛山市广佛跨界水环境治理实践为例,分析广佛跨界河流污染整治面临的主要问题并着重提出相关治理建议。 展开更多
关键词 山水林田湖草生命共同体 水环境 系统治理
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