Eight factors, including forest coverage, fuel load, species composition, elevation, monthly mean temperature, monthly mean relative humidity, monthly mean wind velocity, and monthly mean precipitation of fire season,...Eight factors, including forest coverage, fuel load, species composition, elevation, monthly mean temperature, monthly mean relative humidity, monthly mean wind velocity, and monthly mean precipitation of fire season, were considered and the methods of weight, the cumulative probability, ARC/INFO technique, and raster-to-vector conversion were adopted in division of forest fuel type area. Firstly, the electronic maps of forest distribution and administrative divisions were built, then overlaid and transformed to the real-world coordinates. Finally, the forest fuel type areas of Heilongjiang Province including 81 counties were divided into five grades, accounting for 16%, 17%, 17%, 11%, and 38% respectively. The grade Ⅰ fuel type areas with highest fire danger rating mainly distributed on Daxinganling Mountains, Xiaoxinganling Mountains, and Zhangguangcailing Mountains, the grade Ⅴ fuel type areas mainly centralized on Songnen Plain, Sanjiang Plain, and other Plains, and other forest fuel type areas (grades Ⅱ, Ⅲ, and Ⅳ) were situated between plains and mountainous areas.展开更多
Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana,...Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .展开更多
This paper makes a brief introduction of the ecological environment, forestry achievements, and the existing questions of Jilin Province. The task of forest ecological network and eight questions demanding prompt solu...This paper makes a brief introduction of the ecological environment, forestry achievements, and the existing questions of Jilin Province. The task of forest ecological network and eight questions demanding prompt solution were discussed based on the present situation of forestry in Jilin Province. The author also made prospects for future application of bio-technique, infor-mation technology, new material technology and nuisance-free forest health technology in forest ecological network.展开更多
With the help of GIS tool of ARC/INFO, ARCVIEW and FRAGSTATS, the map of forest resource distribution of Heilongjiang Province was analyzed in 1896, 1949 and 1981. Using total area, mean patch size, patch density, coe...With the help of GIS tool of ARC/INFO, ARCVIEW and FRAGSTATS, the map of forest resource distribution of Heilongjiang Province was analyzed in 1896, 1949 and 1981. Using total area, mean patch size, patch density, coefficient of patch size variation, mean patch fractal dimension and mean shape index, we studied the change of forest landscape pattern and the change of each patch types in this region. As a result, the total area of forest landscape and mean patch size decreased sharply, the quantity and density of patches increased, the juxtaposition of patches weakened, the shape of patch tended to become regular, and the border of patch simplified. All these showed that the forest landscape of this area tended to fragment gradually, and the fragment of Korean pine forest is the severest. The diversity of whole forest landscape and the evenness of landscape types distribution reduced gradually. Human impact, instead of climate change and forest community succession, is the most important reason for such dramatic changes.展开更多
Seven species of family Cleridae are reported from Heilongjiang Province in the present paper, including one species, Orthrius striatulus (Motschlsky), which is firstly recorded from China. Distributional data and a...Seven species of family Cleridae are reported from Heilongjiang Province in the present paper, including one species, Orthrius striatulus (Motschlsky), which is firstly recorded from China. Distributional data and adult photos for all the species and brief diagnosis for new record species are also provided.展开更多
Hunan Province is rich in red tourism resources, and many scenic spots in the region proudly echo the glory of China's revolutionary history. Publicity materials of red tourism in Hunan Province play the role of p...Hunan Province is rich in red tourism resources, and many scenic spots in the region proudly echo the glory of China's revolutionary history. Publicity materials of red tourism in Hunan Province play the role of publicizing and promoting historical sites and places linked with China's revolutionary history. However, at present the C-E translation of publicity materials of red tourism in Hunan province is far from satisfaction. Reasonable application of eco-translatology in C-E translation of publicity materials of red tourism in Hunan Province will allow the translator to enjoy a much greater degree of flexibility in translating and produce appropriate translation which produce functionally the same effect on the target readers as the original on the readers.展开更多
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 i...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/m^3 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,NO_2, CO and SO_2 in air pollutants while meteorological factors were secondary.展开更多
We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77...We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77 x 106 ha in 1979 to 2.32 x 106 ha in 2006, and the forest carbon storage, estimated by the continuous biomass expansion factor method, increased from 83.14 to 100.66 Tg, equivalent to a carbon accumulation rate of 0.0071 Tg per year during the period. Mean carbon densities were 44.83-48.50 t ha-1 and the values decreased slightly over the time period. Natural forests generated greater car- bon storage and density than did plantations. By regression analysis, forest stand age was an important parameter incarbon density studies. We developed various regression equations between carbon density and stand age for major types of natural forests and plantations in the region. Our results can be used for proper selection of re-forestation species and efficient management of young and middle-aged forests, offering great potential for future carbon sequestra- tion, especially in arid and semi-arid regions.展开更多
Yunnan Province is the main distributing area ofJatropha curcas L. This plant is abundant in several drainage areas of the dry-hot, dry-warm and sub-humid valleys in the south subtropical area of Yunnan Province. The ...Yunnan Province is the main distributing area ofJatropha curcas L. This plant is abundant in several drainage areas of the dry-hot, dry-warm and sub-humid valleys in the south subtropical area of Yunnan Province. The seeds that were picked from trees blossoming between April and May and fructifying between September and October will have large seed yield and fine quality. For developing bio-diesel stock forest ofJ. curcas in areas with adaptive climate, seeding measures for afforestation should be taken and techniques on breeding, fast-growing, and high-yielding plantation cultivation are very important.展开更多
Background:Accurate mapping of forest canopy heights at a fine spatial resolution over large geographical areas is challenging.It is essential for the estimation of forest aboveground biomass and the evaluation of for...Background:Accurate mapping of forest canopy heights at a fine spatial resolution over large geographical areas is challenging.It is essential for the estimation of forest aboveground biomass and the evaluation of forest ecosystems.Yet current regional to national scale forest height maps were mainly produced at coarse-scale.Such maps lack spatial details for decision-making at local scales.Recent advances in remote sensing provide great opportunities to fill this gap.Method:In this study,we evaluated the utility of multi-source satellite data for mapping forest heights over Hunan Province in China.A total of 523 plot data collected from 2017 to 2018 were utilized for calibration and validation of forest height models.Specifically,the relationships between three types of in-situ measured tree heights(maximum-,averaged-,and basal area-weighted-tree heights)and plot-level remote sensing metrics(multispectral,radar,and topo variables from Landsat,Sentinel-1/PALSAR-2,and SRTM)were analyzed.Three types of models(multilinear regression,random forest,and support vector regression)were evaluated.Feature variables were selected by two types of variable selection approaches(stepwise regression and random forest).Model parameters and model performances for different models were tuned and evaluated via a 10-fold cross-validation approach.Then,tuned models were applied to generate wall-to-wall forest height maps for Hunan Province.Results:The best estimation of plot-level tree heights(R2 ranged from 0.47 to 0.52,RMSE ranged from 3.8 to 5.3 m,and rRMSE ranged from 28%to 31%)was achieved using the random forest model.A comparison with existing forest height maps showed similar estimates of mean height,however,the ranges varied under different definitions of forest and types of tree height.Conclusions:Primary results indicate that there are small biases in estimated heights at the province scale.This study provides a framework toward establishing regional to national scale maps of vertical forest structure.展开更多
We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests w...We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10;g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.展开更多
China has undergone tremendous economic growth,but there still remains much room for improvement inemergency medical service (EMS) system.[1] The EMSin China comprises of three parts: the pre-hospitalemergency serv...China has undergone tremendous economic growth,but there still remains much room for improvement inemergency medical service (EMS) system.[1] The EMSin China comprises of three parts: the pre-hospitalemergency service, the emergency department, andthe intensive care unit. Not much is known about theexact numbers of out-of-hospital cardiac arrest (OHCA)across the whole of China, though there are reports fromspecifi c provinces.展开更多
Precipitation in Heilongjiang Province of China increased slightly from 1960 to 2000. Adopting the method proposed by Arthur N. Samel, we separated monsoon rainband rain and calculated the initial and final date of mo...Precipitation in Heilongjiang Province of China increased slightly from 1960 to 2000. Adopting the method proposed by Arthur N. Samel, we separated monsoon rainband rain and calculated the initial and final date of monsoon rainband of each year and each station, For the period of 1960-2000, the change of annual precipitation in Heilongjiang Province, with an increasing trend of 2.229 mm per decade, is not significant; the duration and total monsoon rain decreased significantly, with a decreasing trend of -6.9 day per decade and -17,5 mm per decade separately. That change comes from early leaving date of summer monsoon rainband for the period of 1960- 1975 and later arriving date of summer monsoon rainband for the period of 1990-2000, The weakening of summer monsoon makes ils contribution to the annual precipitation decreased significantly, with a decreasing trend of 4.4 % per decade.展开更多
Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species an...Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species and environmental gradient. The forest plant species diversity was analyzed by the diversity index, and the environmental factors was quantified by the method of Whittaker's quantification of environmental gradient. Meanwhile, β-diversity indexes of communities were calculated with similar measurements. The results showed that the Shannon-wiener diversity index of forest plant species increased with the increase of the environmental gradient, and the β-diversity indexes of communities showed a liner increase along with the change of environmental gradient.展开更多
This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and datab...This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and database technology to the research of alien species. The modules of alien species database, including classified data input, statistics and analysis, species pictures and distribution maps, and out date input, were approached by Visual Studio.net 2003 and Microsoft SQL server 2000. The alien species information contains the information of classification, species distinction characteristics, biological characteristics, original area, distribution area, the entering fashion and route, invasion time, invasion reason, interaction with the endemic species, growth state, danger state and spatial information, i.e. distribution map. Based on the above bases, several models including application, checking, modifying, printing, adding and returning models were developed. Furthermore, through the establishment of index tables and index maps, we can also spatially query the data like picture, text and GIS map data. This research established the technological platform of sharing information about scientific resource of alien species in Shandong Province, offering the basis for the dynamic inquiry of alien species, the warning technology of prevention and the fast reaction system. The database application system possessed the principles of good practicability, friendly user interface and convenient usage. It can supply full and accurate information inquiry services of alien species for the users and provide functions of dynamically managing the database for the administrator.展开更多
The origin of overpressure and its effect on petroleum accumulation in the large Permian/Triassic conglomerate oil province in the Mahu Sag,Junggar Basin have been investigated based on comprehensive analysis of log c...The origin of overpressure and its effect on petroleum accumulation in the large Permian/Triassic conglomerate oil province in the Mahu Sag,Junggar Basin have been investigated based on comprehensive analysis of log curve combinations,loading-unloading curves,sonic velocity-density cross-plot,and porosity comparison data.The study results show that there are two kinds of normal compaction models in the study area,namely,two-stage linear model and exponent model;overpressure in the large conglomerate reservoirs including Lower Triassic Baikouquan Formation and Permian Upper and Lower Wu’erhe Formations is the result of pressure transfer,and the source of overpressure is the overpressure caused by hydrocarbon generation of Permian Fengcheng Formation major source rock.The petroleum migrated through faults under the driving of hydrocarbon generation overpressure into the reservoirs to accumulate,forming the Permian and Triassic overpressure oil and gas reservoirs.The occurrence and distribution of overpressure are controlled by the source rock maturity and strike-slip faults connecting the source rock and conglomerate reservoirs formed from Indosinian Movement to Himalayan Movement.As overpressure is the driving force for petroleum migration in the large Mahu oil province,the formation and distribution of petroleum reservoirs above the source rock in this area may have a close relationship with the occurrence of overpressure.展开更多
The biodiversity was studied in 26 communities with different structures in Maoershan National Park and Liangshui Natural Reserve of Northeast Forestry University in Heilongjiang Province, China. Composition index (C...The biodiversity was studied in 26 communities with different structures in Maoershan National Park and Liangshui Natural Reserve of Northeast Forestry University in Heilongjiang Province, China. Composition index (CI) was taken as a parameter to quantify the community dynamics, which can nicely describe forest community dynamics, meanwhile, the relationship between diversity and community dynamics were also investigated and analyzed. Results showed that the total number species of community, richness, evenness, and Shannon-Wiener diversity index were obviously different in every community. The richness decreased with the increasing CI of every community, which means richness was in inverse proportion to community dynamics. The Shannon-Wiener index of every community increased from the initial stage to the middle stage of succession, and then decreased in the climax stage. The coverage weighted foliage-height diversity index increased along with the increase of CI, which was similar as the oattem diversity.展开更多
Selecting the optimum location with attention to conditions and restrictions is one of the most importantfactors in establishing a manufacturing plant. Identification of effective criteria is an important stage in the...Selecting the optimum location with attention to conditions and restrictions is one of the most importantfactors in establishing a manufacturing plant. Identification of effective criteria is an important stage in the selection for the location of industrial units. In this study, an analytic hierarchy process (AHP) was applied to select the most effective criteria for the location of MDF (medium density fiberboard) industry in Mazandaran Province, Iran. A consideration in ttaining this goal is that Mazandaran is favored over other provinces because of its resources of raw lignocellulosic ma- erial required for wood and paper industries. The results indicate that the criterion of "materials and products" and the ub-criterion of "reliability of supply of raw material" are the most important factors.展开更多
Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped int...Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped into a rapid development period in China as well as the research of interpreting studies. This paper aimed at providing a brief introduction of the current situation and existing problems of English interpreting studies in Three Northeastern Provinces of China under the comparative analysis of literature in CNKI China Academic Journal Network Publishing Database from 2004 to 2013.展开更多
英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provi...英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provinces of Western China所做的翻译研究不多。因此,文章拟以关联理论为指导,从词汇、句子两个层面分析来华游记The Provinces of Western China中的汉译实例,从而总结关联理论,希望对来华游记汉译具有指导意义。展开更多
基金The paper was supported by National Nature Science Foundation of China (No.39870636).
文摘Eight factors, including forest coverage, fuel load, species composition, elevation, monthly mean temperature, monthly mean relative humidity, monthly mean wind velocity, and monthly mean precipitation of fire season, were considered and the methods of weight, the cumulative probability, ARC/INFO technique, and raster-to-vector conversion were adopted in division of forest fuel type area. Firstly, the electronic maps of forest distribution and administrative divisions were built, then overlaid and transformed to the real-world coordinates. Finally, the forest fuel type areas of Heilongjiang Province including 81 counties were divided into five grades, accounting for 16%, 17%, 17%, 11%, and 38% respectively. The grade Ⅰ fuel type areas with highest fire danger rating mainly distributed on Daxinganling Mountains, Xiaoxinganling Mountains, and Zhangguangcailing Mountains, the grade Ⅴ fuel type areas mainly centralized on Songnen Plain, Sanjiang Plain, and other Plains, and other forest fuel type areas (grades Ⅱ, Ⅲ, and Ⅳ) were situated between plains and mountainous areas.
文摘Through five years (1996-2000) experiment, the growth characteristics and resistance to insect and cold of the seven poplar varieties including P. po pularis, P. opera, P. pseudo-simonii, P. beijinensis, P. bolleana, P. ( eurameri cana and P. simonii, which were planted in loess hilly land in northwest Shanxi Province, were tested under different planting densities and site conditions. A randomized block design and three times repetition were adopted in the test. Bas ed on the test results in arid and cold area of the northwest Shanxi, the hybrid poplar trees taking Populus cathaysna as their female parent could be selected for afforestation, such as P. popularis and P. opera, and the growing space of s ingle plant should be larger than 20 m2. P. bolleana as an introduced tree speci es grows well in this area, but its growth is likely affected by ground water co ndition. On the site with relatively abundant soil water, P. bolleana usually su ffer from frost crack at its trunk base. As a result, P. bolleara is suited to p lanting in the site where is short of soil water. P. x euramericana is not suita ble for large-scale afforestation, especially in arid slopes and ridges of loess hilly land .
文摘This paper makes a brief introduction of the ecological environment, forestry achievements, and the existing questions of Jilin Province. The task of forest ecological network and eight questions demanding prompt solution were discussed based on the present situation of forestry in Jilin Province. The author also made prospects for future application of bio-technique, infor-mation technology, new material technology and nuisance-free forest health technology in forest ecological network.
基金The research is supported by Study on the interaction of global change and terrestrial ecosystem in eastern China - 39899370 and the Northeast Forestry University research fund.
文摘With the help of GIS tool of ARC/INFO, ARCVIEW and FRAGSTATS, the map of forest resource distribution of Heilongjiang Province was analyzed in 1896, 1949 and 1981. Using total area, mean patch size, patch density, coefficient of patch size variation, mean patch fractal dimension and mean shape index, we studied the change of forest landscape pattern and the change of each patch types in this region. As a result, the total area of forest landscape and mean patch size decreased sharply, the quantity and density of patches increased, the juxtaposition of patches weakened, the shape of patch tended to become regular, and the border of patch simplified. All these showed that the forest landscape of this area tended to fragment gradually, and the fragment of Korean pine forest is the severest. The diversity of whole forest landscape and the evenness of landscape types distribution reduced gradually. Human impact, instead of climate change and forest community succession, is the most important reason for such dramatic changes.
基金The research was supported by the Key Project of Heilongjiang Province (No.GC02B202).
文摘Seven species of family Cleridae are reported from Heilongjiang Province in the present paper, including one species, Orthrius striatulus (Motschlsky), which is firstly recorded from China. Distributional data and adult photos for all the species and brief diagnosis for new record species are also provided.
文摘Hunan Province is rich in red tourism resources, and many scenic spots in the region proudly echo the glory of China's revolutionary history. Publicity materials of red tourism in Hunan Province play the role of publicizing and promoting historical sites and places linked with China's revolutionary history. However, at present the C-E translation of publicity materials of red tourism in Hunan province is far from satisfaction. Reasonable application of eco-translatology in C-E translation of publicity materials of red tourism in Hunan Province will allow the translator to enjoy a much greater degree of flexibility in translating and produce appropriate translation which produce functionally the same effect on the target readers as the original on the readers.
基金supported by the Natural Science Foundation of Heilongjiang Province,China(Grant No.G2016001)
文摘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/m^3 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,NO_2, CO and SO_2 in air pollutants while meteorological factors were secondary.
基金financially supported by the Chinese Academy of Sciences through the Strategic Priority Research Program(XDA05050202)
文摘We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979-2006. Total forest area increased from 1.77 x 106 ha in 1979 to 2.32 x 106 ha in 2006, and the forest carbon storage, estimated by the continuous biomass expansion factor method, increased from 83.14 to 100.66 Tg, equivalent to a carbon accumulation rate of 0.0071 Tg per year during the period. Mean carbon densities were 44.83-48.50 t ha-1 and the values decreased slightly over the time period. Natural forests generated greater car- bon storage and density than did plantations. By regression analysis, forest stand age was an important parameter incarbon density studies. We developed various regression equations between carbon density and stand age for major types of natural forests and plantations in the region. Our results can be used for proper selection of re-forestation species and efficient management of young and middle-aged forests, offering great potential for future carbon sequestra- tion, especially in arid and semi-arid regions.
文摘Yunnan Province is the main distributing area ofJatropha curcas L. This plant is abundant in several drainage areas of the dry-hot, dry-warm and sub-humid valleys in the south subtropical area of Yunnan Province. The seeds that were picked from trees blossoming between April and May and fructifying between September and October will have large seed yield and fine quality. For developing bio-diesel stock forest ofJ. curcas in areas with adaptive climate, seeding measures for afforestation should be taken and techniques on breeding, fast-growing, and high-yielding plantation cultivation are very important.
基金This work was funded by the Open Fund of State Key Laboratory of Remote Sensing Science(OFSLRSS201904)National Natural Science Foundation of China(41901351)+1 种基金Start-up Program of Wuhan University(2019-2021)Natural Science Foundation of Ningxia Province(2021AAC03017).
文摘Background:Accurate mapping of forest canopy heights at a fine spatial resolution over large geographical areas is challenging.It is essential for the estimation of forest aboveground biomass and the evaluation of forest ecosystems.Yet current regional to national scale forest height maps were mainly produced at coarse-scale.Such maps lack spatial details for decision-making at local scales.Recent advances in remote sensing provide great opportunities to fill this gap.Method:In this study,we evaluated the utility of multi-source satellite data for mapping forest heights over Hunan Province in China.A total of 523 plot data collected from 2017 to 2018 were utilized for calibration and validation of forest height models.Specifically,the relationships between three types of in-situ measured tree heights(maximum-,averaged-,and basal area-weighted-tree heights)and plot-level remote sensing metrics(multispectral,radar,and topo variables from Landsat,Sentinel-1/PALSAR-2,and SRTM)were analyzed.Three types of models(multilinear regression,random forest,and support vector regression)were evaluated.Feature variables were selected by two types of variable selection approaches(stepwise regression and random forest).Model parameters and model performances for different models were tuned and evaluated via a 10-fold cross-validation approach.Then,tuned models were applied to generate wall-to-wall forest height maps for Hunan Province.Results:The best estimation of plot-level tree heights(R2 ranged from 0.47 to 0.52,RMSE ranged from 3.8 to 5.3 m,and rRMSE ranged from 28%to 31%)was achieved using the random forest model.A comparison with existing forest height maps showed similar estimates of mean height,however,the ranges varied under different definitions of forest and types of tree height.Conclusions:Primary results indicate that there are small biases in estimated heights at the province scale.This study provides a framework toward establishing regional to national scale maps of vertical forest structure.
基金funded by the National Key Research and Development Program of China(2016YFC0501605)the National Sci-Tech Basic Program of China(2014FY210100)+1 种基金the National Natural Science foundation of China(31200332)the University Youth Teacher Training Program by Education Department of Henan Province(2016GGJS-062)
文摘We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10;g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.
文摘China has undergone tremendous economic growth,but there still remains much room for improvement inemergency medical service (EMS) system.[1] The EMSin China comprises of three parts: the pre-hospitalemergency service, the emergency department, andthe intensive care unit. Not much is known about theexact numbers of out-of-hospital cardiac arrest (OHCA)across the whole of China, though there are reports fromspecifi c provinces.
文摘Precipitation in Heilongjiang Province of China increased slightly from 1960 to 2000. Adopting the method proposed by Arthur N. Samel, we separated monsoon rainband rain and calculated the initial and final date of monsoon rainband of each year and each station, For the period of 1960-2000, the change of annual precipitation in Heilongjiang Province, with an increasing trend of 2.229 mm per decade, is not significant; the duration and total monsoon rain decreased significantly, with a decreasing trend of -6.9 day per decade and -17,5 mm per decade separately. That change comes from early leaving date of summer monsoon rainband for the period of 1960- 1975 and later arriving date of summer monsoon rainband for the period of 1990-2000, The weakening of summer monsoon makes ils contribution to the annual precipitation decreased significantly, with a decreasing trend of 4.4 % per decade.
基金Foundation project: The paper was supported by National Natural Science Foundation of China (39899370).
文摘Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species and environmental gradient. The forest plant species diversity was analyzed by the diversity index, and the environmental factors was quantified by the method of Whittaker's quantification of environmental gradient. Meanwhile, β-diversity indexes of communities were calculated with similar measurements. The results showed that the Shannon-wiener diversity index of forest plant species increased with the increase of the environmental gradient, and the β-diversity indexes of communities showed a liner increase along with the change of environmental gradient.
基金this study was supported by the Key Project of Natu-ral Science Foundation of Shandong Province(No. Z2003D05)Key Project of Environmental Protection Science of Shandong Province(No. 2004057)Outstanding Young Scientists Grants of Shandong Province(No.2005BS08010),China
文摘This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and database technology to the research of alien species. The modules of alien species database, including classified data input, statistics and analysis, species pictures and distribution maps, and out date input, were approached by Visual Studio.net 2003 and Microsoft SQL server 2000. The alien species information contains the information of classification, species distinction characteristics, biological characteristics, original area, distribution area, the entering fashion and route, invasion time, invasion reason, interaction with the endemic species, growth state, danger state and spatial information, i.e. distribution map. Based on the above bases, several models including application, checking, modifying, printing, adding and returning models were developed. Furthermore, through the establishment of index tables and index maps, we can also spatially query the data like picture, text and GIS map data. This research established the technological platform of sharing information about scientific resource of alien species in Shandong Province, offering the basis for the dynamic inquiry of alien species, the warning technology of prevention and the fast reaction system. The database application system possessed the principles of good practicability, friendly user interface and convenient usage. It can supply full and accurate information inquiry services of alien species for the users and provide functions of dynamically managing the database for the administrator.
基金Supported by the National Natural Science Foundation of China(41502132)the China National Science and Technology Major Project(2017ZX05001-004)
文摘The origin of overpressure and its effect on petroleum accumulation in the large Permian/Triassic conglomerate oil province in the Mahu Sag,Junggar Basin have been investigated based on comprehensive analysis of log curve combinations,loading-unloading curves,sonic velocity-density cross-plot,and porosity comparison data.The study results show that there are two kinds of normal compaction models in the study area,namely,two-stage linear model and exponent model;overpressure in the large conglomerate reservoirs including Lower Triassic Baikouquan Formation and Permian Upper and Lower Wu’erhe Formations is the result of pressure transfer,and the source of overpressure is the overpressure caused by hydrocarbon generation of Permian Fengcheng Formation major source rock.The petroleum migrated through faults under the driving of hydrocarbon generation overpressure into the reservoirs to accumulate,forming the Permian and Triassic overpressure oil and gas reservoirs.The occurrence and distribution of overpressure are controlled by the source rock maturity and strike-slip faults connecting the source rock and conglomerate reservoirs formed from Indosinian Movement to Himalayan Movement.As overpressure is the driving force for petroleum migration in the large Mahu oil province,the formation and distribution of petroleum reservoirs above the source rock in this area may have a close relationship with the occurrence of overpressure.
基金The paper was supported by National Natural Science Foundation of China (39899370).
文摘The biodiversity was studied in 26 communities with different structures in Maoershan National Park and Liangshui Natural Reserve of Northeast Forestry University in Heilongjiang Province, China. Composition index (CI) was taken as a parameter to quantify the community dynamics, which can nicely describe forest community dynamics, meanwhile, the relationship between diversity and community dynamics were also investigated and analyzed. Results showed that the total number species of community, richness, evenness, and Shannon-Wiener diversity index were obviously different in every community. The richness decreased with the increasing CI of every community, which means richness was in inverse proportion to community dynamics. The Shannon-Wiener index of every community increased from the initial stage to the middle stage of succession, and then decreased in the climax stage. The coverage weighted foliage-height diversity index increased along with the increase of CI, which was similar as the oattem diversity.
文摘Selecting the optimum location with attention to conditions and restrictions is one of the most importantfactors in establishing a manufacturing plant. Identification of effective criteria is an important stage in the selection for the location of industrial units. In this study, an analytic hierarchy process (AHP) was applied to select the most effective criteria for the location of MDF (medium density fiberboard) industry in Mazandaran Province, Iran. A consideration in ttaining this goal is that Mazandaran is favored over other provinces because of its resources of raw lignocellulosic ma- erial required for wood and paper industries. The results indicate that the criterion of "materials and products" and the ub-criterion of "reliability of supply of raw material" are the most important factors.
文摘Since the Master of Translation and Interpreting has been established under the approval of the Academic Degrees Committee of the State Council and the Chinese Ministry of Education, translation discipline stepped into a rapid development period in China as well as the research of interpreting studies. This paper aimed at providing a brief introduction of the current situation and existing problems of English interpreting studies in Three Northeastern Provinces of China under the comparative analysis of literature in CNKI China Academic Journal Network Publishing Database from 2004 to 2013.
文摘英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provinces of Western China所做的翻译研究不多。因此,文章拟以关联理论为指导,从词汇、句子两个层面分析来华游记The Provinces of Western China中的汉译实例,从而总结关联理论,希望对来华游记汉译具有指导意义。