Table of Content

28 August 2019, Issue 4

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Discussion on the Assessment System of the Social Service Function of Urban Forests — Analysis from the Perspective of Citizen Benefit

ZHAO Zheng, LIU Yunlong, WEN Yali

2019,(4):  1-9.  doi:10.13466/j.cnki.lyzygl.2019.04.001

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In this study,four typical types of urban forest function were extracted from the social attributes of urban forests and the value attributes of citizens.Based on the existing research results and the actual situation of Beijing,an evaluation index system of urban forest function was constructed.On this basis,the importance of each function is discussed by using the method of entropy value,the overall level of urban forest function is evaluated and scored by using the method of fuzzy comprehensive evaluation and grade parameter evaluation,and the difference evaluation results of urban forest function under different citizen characteristics are evaluated by using the method of one-way ANOVA.The results show that:(1) Citizens value the benefits of urban forests in terms of education and culture,rather than the traditional health functions of urban forests;(2) Citizens believe that the function of urban forest is still in the lower middle level,especially the function of education and culture is not well developed;(3) Citizens' evaluation of urban forest function shows significant differences due to age,educational background,monthly income,residential location and length of residence in Beijing.

Prediction and Simulation of the Potential Demand for Forest Carbon Sequestration in Seven Pilot Carbon Markets

TONG Huiqin, LONG Fei, QI Huibo, ZHANG Zhe

2019,(4):  10-17.  doi:10.13466/j.cnki.lyzygl.2019.04.002

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The article takes 7 pilot cities and provinces in Beijing,Tianjin,Shanghai,Hubei,Chongqing,Guangdong,Shenzhen as the case area,and uses the directional distance function to obtain the carbon marginal abatement cost of the industrial sector in each case area,and adopts the cloud model.The simulation method will make a scientific prediction on the forest carbon sequestration demand potential of the pilot provinces and cities in the next 10 years,and then carry out policy simulation research on how to improve the forest carbon sequestration demand of the pilot provinces and cities in the next 10 years.The results show that there are great differences in the carbon marginal abatement costs of the industrial industries in the seven pilot provinces and cities in China,such as the enterprise's super-discharge penalty rate,industrial incentive policies,self-technology emission reduction subsidies,and the intensity of corporate carbon emission quotas.The four policy factors have different effects on the demand potential of forest carbon sequestration in the emission reduction industry.Based on the combined impact calculation and analysis of different policy factors,the article concludes with relevant policy recommendations on how to improve the total demand for forest carbon sequestrations in the next seven pilot provinces and cities.

An Analysis on Factors Affecting the Preservation and Establishment of Plantation in Arid Areas of Northwest China

MA Zhenhua, LI Caiwen

2019,(4):  18-23.  doi:10.13466/j.cnki.lyzygl.2019.04.003

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Based on the results of comprehensive verification of plantation in Northwest monitoring area in 2018,this paper makes a statistical analysis of the results of the investigation on the preservation and afforestation rate of plantation in northwest arid area from 2008 to 2012,and summarizes the main characteristics of the preservation and afforestation rate of plantation in Northwest arid area.The main factors affecting the preservation and afforestation of plantation in the region were analyzed from the aspects of natural disasters such as drought,suitable afforestation land,growth status of young trees,follow-up management and stand structure.Suggestions were put forward to improve the central investment standard,strengthen the follow-up management of afforestation,scientifically and rationally arrange afforestation,take correspording vegetation restoration measures according to different corditions.

Effects of Slopes on Chinese Pine Growth in Mountain Areas of Northern Hebei

LI Xiao, JIANG Lingling, XU Zhongqi, JIA Yanlong, MA Rong

2019,(4):  24-30.  doi:10.13466/j.cnki.lyzygl.2019.04.004

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In order to understand the influence of slope position on the growth of Chinese pine(Pinus tabuliformis),the Chinese pine forests located in the slope and slope top were investigated,in the northern mountain area of Hebei province.The results showed that the annual growth,average growth and total growth of Chinese pine on the slope were significantly higher than that on the slope top,and the difference between them was about 9cm for average growth,but the topography had no significant effect on the growth of DBH.Under the two topographic conditions,the annual growth of tree height was relatively stable with the increase of age,while the annual growth of DBH increased ten years ago,then decreased,and dropped to the lowest around 20 years.The interannual variability for growth of height and DBH of Chinese pine showed obvious synchronicity under two topographic conditions,indicating that the growth of height and DBH of Chinese pine was sensitive to interannual climate change.There was a higher correlation between the annual height growth of Chinese pine and the DBH growth of the previous year,indicating that the climatic conditions of the previous year had a significant influence on the annual height growth of Chinese pine.The height growth of Chinese pine was mainly affected by topography and climate,while the DBH growth was affected by stand factor and climate.The slope topography is more suitable for the growth of Chinese pine,and Chinese pine forest located on the slope can be used to cultivate high-quality wood,and Chinese pine forests distributed on the top of the slope should be used as ecological forests for protection and management.

Effects of Forest Gaps on the Regeneration Pattern of the Undergrowth of Secondary Poplar-Birch Forests in Southern Greater Xing'an Mountains

LIU Bingbing, ZHAO Pengwu, ZHOU Mei, WANG Yuan, YANG Liu, SHU Yang

2019,(4):  31-36.  doi:10.13466/j.cnki.lyzygl.2019.04.005

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The effects of different forest gap sizes on the regeneration pattern of the undergrowth of secondary Poplar-birch were studied,which provided theoretical basis and reference for the artificial near-natural simulation of forest gap disturbance renewal.Taking the secondary Poplar-birch forest in the Southern Greater Xing'an Mountains,Inner Mongolia as the research object,the 6hm2 large plots were divided into the upper part,the middle and the lower part of slopes according to the altitude gradient.Each slope was divided into 4 forest gap area grades,and each grade was selected 3 forest gaps of different sizes,as three repetitions,36 forest gaps are selected for each slope position,and 5regeneration seedling survey samples are set in each forest gap.At the same time,36 control samples (CK) of the same area were set.A total of 180 regeneration seedlings samples and 180 CK samples were set up and surveyed in the forest gaps.The results showed that the forest gap had the tendency to decrease the regeneration density of the original pioneer species (Mongolian scorpion); the sorghum in the forest gap was the main renewed species.From the lower part,to the middle part and the upper part of slopes,the regeneration seedling density of Quercus mongolica accounted for 61.9%,50% and 39.86% of the total renewal density respectively.The regenerated seedlings in the forest gaps are mainly low-lying plants (<60 cm),and the number of regenerated seedlings show a decrease with an increase of height level in different slope positions and different forest gap areas.The number of regenerated seedlings in different heights of different slopes showed that there were more large forest gaps than small ones.The slope position and forest gap area all had significant effects on the algae diameter of Quercus mongolica (p<0.05),forest gaps could significantly promote the regeneration of Quercus mongolica.The growth of seedlings was the largest in the forest gap area of 80-100 m ².The diameter of the seedlings in the forest gapin the lower part and the upper part of slopes were higher than those in the forest,and there was no such performance in the middle part of slopes.In general,forest gaps can significantly promote the regeneration and growth of undergrowth species,and have a tendency to reduce the density of regeneration of the original pioneer speciesMongolian mongolica.

A Prediction on the Potential Suitable Areas of Zelkova Schneideriana in Zhejiang Province Using Maximum Entropy Model

SUN Jiejie, JIANG Bo, QIU Haojie, GUO Jiahuan, Yuan Weigao, WU Danting, XU Xuan, WU Chuping, JIAO Jiejie, SHEN Aihua

2019,(4):  37-45.  doi:10.13466/j.cnki.lyzygl.2019.04.006

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Studying the potential suitable habitats of endangered species Zelkova schneideriana and their response to environmental factors will be helpful to the work of site conservation and population expansion of Z.schneideriana.Based on a comprehensive survey data of 21 Z.schneideriana samples taken from Zhejiang ecological monitoring sample plots database,using ArcGIS and MaxEnt model adopted to predict its potential distribution area in Zhejiang.Then screen the dominant environmental factors and their optimal range.The mean AUC value of 17 simulations is 0.891,which indicated the model simulation has high precision.The result showed that the highly suitable growth area of Z.schneideriana in Zhejiang is mainly in the Wuyi—Suichang area in the west of Zhejiang,and Pujiang—Qiandaohu River basin,Ningbo—Zhoushan island,coastal area in Wenzhou and the surrounding area,the area is 6 thousand km ².The MaxEnt show that precipitation seasonality(coefficient of variation),slope,mean air temperature of the wettest quarter and mean air temperature of the driest quarter are the main environmental factors that affect the distribution of Z.schneideriana.The most suitable range of them are 30~42 in precipitation seasonality(coefficient of variation),3~20° in slope,14~21℃ in mean air temperature of the wettest quarter,0~7℃ in mean air temperature of the driest quarter.

Developing Models for Tree Height Curves of Main Conifer Species in Yunnan Province

QIN Yangping, LI Hua, LI Yongliang, ZHANG Chengcheng, WANG Meng

2019,(4):  46-51.  doi:10.13466/j.cnki.lyzygl.2019.04.007

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Tree height curve plays an important role in the forest management and yield regulation,the tree height curve model for main conifer species in Yunnan Province was established to provide reference for its forest management.Based on two periods of national forest inventory data in Yunnan Province,this paper takes Abies fabri,Pinus kesiya var.langbianensis,Pinus yunnanensis,Pinus armandii,Cunninghamia lanceolata as research objects,Richards etc.fifteen tree height curve models were selected as alternative models,the coefficient of determination,root mean square error,mean absolute error,total relative error and mean predict error were used as the evaluation indicators of the pros and cons of the model.The results show that Hossfeld can better describe the tree height curve of Abies fabri and Cunninghamia lanceolata,hyperbola can better describe the tree height curve of Pinus yunnanensis and Pinus armandii,Wykoff can better describe the tree height curve of Pinus kesiya var.langbianensis.The coefficient of determination of the optimal tree height curve model of Pinus yunnanensis is 0.676,and the coefficient of determination of other conifer tree specieses are greater than 0.710,the independent sample data test shows that the optimal tree height curve model of each tree species has good applicability,and has a good prediction effect on the tree height of the main conifer tree species in Yunnan Province.

Analyses on the Impact of Cluster Sampling on Forest Resource Macro-monitoring in Tibet

XING Yuanjun, PUBU Dunzhun, LUO Peng, XU Dengping

2019,(4):  52-58.  doi:10.13466/j.cnki.lyzygl.2019.04.008

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Forest resource monitoring is a basic work of forestry,which is an important part of national investigation.The field observation method to monitor macro-forest resource is time-consuming,labor-intensive and costly.Remote sensing technology provides a practical solution to accurately monitor macro-forest resource.However,sample design,sample size and remote sensing interpretation accuracy have attracted wide publicity in macro-forest resource monitoring.In this paper,cluster sampling and remote sensing visual interpretation methods were applied to estimate forest coverage rate of Tibet.At the same time,the impact of size variation in cluster sampling was analyzed using forest resources macro monitoring in Tibet 2015.The results showed that the sampling accuracy reached the highest 94.49% when the number of sample sizes of each sample plot increased to 25.There was no significant difference between estimated result and actual forest coverage,and the coefficient of variation was stable.Therefore,the cluster sampling method was a feasible and efficient method,and the workload was significantly lower than that of visual interpretation method.

Effects of Thinning on the Growth of Pinuse Elliottii Plantation and the Diversity of Its Undergrowth Vegetation

DONG Kaili, ZHANG Guoxiang, WANG Ruihui, LIU Kaili, ZHAO Suya, GONG Yingyun

2019,(4):  59-68.  doi:10.13466/j.cnki.lyzygl.2019.04.009

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The study was based on 8a pinus elliottii plantation in Jing'an County,Jiangxi Province,sorting it into four thinning intensities,0%(C),15%(L),35%(M),55%(H).Observing the effects of tending and thinning on tree growth and undergrowth vegetation,the results show:with increasing thinning intensity,the distribution of diameter moves right compared with C.The diameter of L and M obey normal distribution but C and H don’t.Clearly,thinning has promoting effects on rise in both diameter and volume with a major difference in annual average growth of diameter between C and H,M,and the average annual growth of volume of C was significantly different from H,but the difference in average annual growth of height is slight.On the whole,thinning makes the number of undergrowth of plantations increase and improve the vegetation layer index of Simpson,Shannon-Wiener and Pielou,the effect which is relatively remarkable in the first two years after experiment,afterwards is weakened.The research results can provide technical support for the management of Pinus elliottii plantation.

Relationship Between Crown Width and DBH of Larix pricipis-rupperchtii with Different Site Types

ZHANG Dongyan, WANG Dongzhi, FAN Dongdong, ZHANG Jiandong, LI Dayong

2019,(4):  69-73.  doi:10.13466/j.cnki.lyzygl.2019.04.010

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The optimal crown amplitude prediction model for Larix principis-rupprechtii plantation was constructed to provide scientific reference for studying its growth and development rules,site quality assessment and productivity prediction.In this study,the plantation of Larix principis-rupprechtii in Saihanba mechanical forest farm in Hebei province was used as the research object.Data from 155 sample plots(30 m by 30 m) were used to classify site types based on the factor analysis and cluster analysis.Constructing crown predication model of Larix principis-rupprechtii plantation on different site types.The results showed that altitude,slope and aspect were the main site factors affecting the crown growth of Larix principis-rupprechtii plantations,and the site types were classified into two ones.According to the determination coefficient R ² of 0.9795 and 0.9834,respectively,Bias of them were respectively 0.0001and0.8259,and RMSE of them were respectively 0.0019 and 0.65718,a site prediction model of the crown amplitude was determined,and a comprehensive comparative analysis of high altitude CW=-2.5972+0.6211D-0.0098D ²and low altitude CW=[D/(4.9823+0.2059D)] ² equation predicts the growth of Larix principis-rupprechtii plantation in Saihanba mechanical forest farm,which provides a theoretical basis for the scientific management of Larix principis-rupprechtii plantation.

Study on Seed Rain and Surface Seed Bank of Betula platyphylla in Different Ages in the Southern Daxing'anling Mountains

FENG Qianqian, ZHOU Mei, ZHAO Pengwu, WU Yiheng

2019,(4):  74-79.  doi:10.13466/j.cnki.lyzygl.2019.04.011

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In the Inner Mongolia Saihanwula National Nature Reserve,the regeneration status of different birch forests is different,with S1(10~15a),S2(20~30a) and S3(40~45a) were the research objects.The differences of provenances and surface seed bank of three different forest ages were analyzed and compared,and the limiting factors of natural regeneration of birch forest were explored.The results showed that:(1) The seed height,litter litterand seed rain 1000-grain weight of different plant ages were consistent with the dynamic height of different distribution periods,and the overall performance was S1>S2>S3;(2)The total number of seed rain in white birch forest is S1(90.48±0.08) grain>S2(88.18±0.09) grain>S3(68.74±0.07) grain;(3)The total seed quantity of white birch forest of different forest age is S1(35273.00±2929.00) grain>S2(32079.00±1770.00) grain>S3(8478.00±432.00) grain,the highest proportion of intact seeds of S1 forest age B.bicolor;(4)The total seed bank of three different ages of white birch population is S1(9882.00/m ²)>S2(8859.00/m ²) >S3(2539.00 granules/m ²),the germination rate of indoor germination experiment of Betula chinensis seed bank was S1(44.30%)>S2(40.10%)>S3(21.20%).It is indicated that the provenance is not the main limiting factor for the natural regeneration of birch forest in Saihanwula region.The forest age is the main factor leading to the uneven renewal of birch forest in Saihanwula.

Study on Spatial Pattern and Interspecific Correlation of Larix principis-rupprechtii Forest

QIN Zhou, HAN Youzhi, ZHANG Mengtao, CHEN Hanxin, CHEN Aolin

2019,(4):  80-85.  doi:10.13466/j.cnki.lyzygl.2019.04.012

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In order to understand the spatial structure of Larix principis-rupprechtii forest in Guandi mountain Nature Reserve and explore the correlation of Larix principis-rupprechtii,10 sample plots of 30m × 30m were set up randomly.All the standing timbers entering the caliper step in the sample land were measured by each wooden ruler.The tree species,diameter,height,crown width,geographic coordinates and environmental factors were measured,the spatial structure analysis was maked based on the angular scale,mixed degree and size ratio,and the correlation analysis between forests and species was carried out by O-ring function.The results showed that:(1) most of the pure forest samples of Larix principis-rupprechtii were randomly distributed,and the mixed forests has obvious cluster distribution.(2) Larix principis-rupprechtii forests showed less correlation at different scales.The fewer the number of Larix principis-rupprechtii in the mixed forest,the more obvious of interspecific association.The research shows that Larix principis-rupprechtii forest is in the transition from moderate to inferior currently,and is beginning to decline from the top community,but Larix principis-rupprechtii is still dominant in the competition of this community,belonging to the dominant population.

Study on the Diversity of Undergrowth Plant in Four Typical Plantations in Huangbaishan Mountain

DONG Huihui, QIU Lin, ZHANG Jianshe, WANG Xiaoyun, ZHEN Tiancai, LI Fengying, ZHOU Chuantao, Yu Kaihui

2019,(4):  86-91.  doi:10.13466/j.cnki.lyzygl.2019.04.013

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Sampling plots were set up in the four typical plantation of Huangbaishan Forest Farm,the composition and diversity of undergrowth plant were studied to understand the undergrowth plant characteristics of forest ecosystems in the region.The results showed that:1) The plant richness of the mixed forest was the highest.2) The Shannon-Wiener diversity index,Simpson diversity index and evenness index of the four types of plantations were significantly different(p<0.05),and the shrub layer and herb layer plant types of each forest were presented as Medium dissimilarity or very dissimilar,indicating that type of arbor have a greater impact on understory species and their diversity.The choice of tree species has an important impact on plantations sustainable management.3) The diversity index of undergrowth plant community of four types of artificial forests,including Shannon-Wiener diversity index,Simpson diversity index and evenness index were herb> shrub.It may because the canopy density of the four forest stands is high,which affects the growth of shrub layer,and also creates some conditions for the growth of herb plants.In the process of plantation management of the Huangbaishan forest farm,tending and thinning should be carried out properly to increase the transparency of the forest,which is conducive to the restoration of undergrowth plant.

GIS-Based Evaluation of Ecological Sensitivity of Yucang Mountain Scenic Spot in Cangnan County

ZHANG Mi, CHEN Cunyou, HU Xijun

2019,(4):  92-100.  doi:10.13466/j.cnki.lyzygl.2019.04.014

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This study selected,Yucang mountain scenic area in Cangna county,Zhejiang as the research object,according to the characteristics of Yucang mountain scenic spot,11 index factors including elevation,slope,slope direction,river,lake,vegetation type,natural landscape type,human landscape type,landscape density,road traffic and land use type were selected,using the analytic hierarchy process(AHP) to obtain the weight of each evaluation factor,then weighted and superimposed to get the comprehensive evaluation and analysis chart of ecological sensitivity,so as to evaluate the ecological sensitivity of Yucang mountain scenic area.Results show that the areas of extremely sensitive area,highly sensitive area,moderately sensitive area,mildly sensitive area and non-sensitive area in the study area are respectively 2.39km ²,5.20km ²,9.00km ²,13.94km ²,14.70km ².The total area of the moderately sensitive areas and above was 16.59km ²,accounting for 36.68% of the total area of the study area.Results can provide a reference for the ecological function regionalization of Yucang mountain scenic area.

Real-time Generation Methods for Stand Three-dimensional Models

LI Yongliang, ZHU Nianfu, ZHANG Huaiqing, PENG Jiankang, YANG Tingdong

2019,(4):  101-106.  doi:10.13466/j.cnki.lyzygl.2019.04.015

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Aiming at the problem of insufficient ability of existing stand visualization simulation methods for representing tree diversity,a proposed method of constructing tree diversity three-dimensional models and the realized real-time establishment of stand three-dimensional models to visualize and visually reflect the three-dimensional structure of the forest.A three-dimensional simulation method of the trunk was proposed,and a 10-parameter power function for controlling crown curves was established to form a multi-direction crown control model of trees.Based on the Bézier curve,10 types of branch models were constructed.The algorithm of branch generation under crown control and the method of leaf simulation were proposed and the real-time construction of tree diversity three-dimensional model was realized.Based on the survey data of each tree,a stand real-time three-dimensional model was established according to the tree morphological data.The results showed that the canopy diversity model was effectively constructed,and the stand survey data could directly provide data support for the stand three-dimensional modeling.This method can realize the intuitive three-dimensional simulation of the tree diversity morphology and stand characteristic factors.

Tree Vertex and Height Extraction Based on UAV Imagery and Analysis on its Influencing Factors

LIU Jiangjun, GAO Haili, FANG Luming, ZHENG Xinyu, JIANG Guangyu

2019,(4):  107-116.  doi:10.13466/j.cnki.lyzygl.2019.04.016

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In this paper,the feasibility of using local maximum algorithm to extract tree vertices and tree height based on the canopy height model(CHM) generated by UAV imagery was discussed.In addition,the effect of resolution and window size on tree vertex extraction was also discussed.In this study,a dense conifer-broadleaf forest is used as sample plot.The SfM(Structure from Motion) algorithm was combined with the UAV images to reconstruct the research area in three dimensions,and a series of three-dimensional data such as point cloud,digital surface model(DSM),digital elevation model(DEM) and CHM were generated.Then,for different resolutions of CHM,different smoothing window size and moving window size combinations were used to extract the tree vertices and the accuracies of results were evaluated.When the CHM resolution is 0.4m,the size of smoothing window is 3×3 pixels,and the size of moving window is 3×3 pixels,the extraction accuracy of tree vertex is the highest,and the F-Measure is 77.08%.The extracted tree heights corresponding to the 37 tree vertices extracted based on the combination was compared with the tree heights measured in the field,and the R ²,RMSE,rRMSE is 0.9669,1.4114m,10.69% respectively.The results showed that UAV imagery can be used to extract tree vertices and tree heights of complex forests.Extracting the tree vertices based on the local maximum algorithm needs to determine the resolution of the CHM,the smoothing window size and the moving window size according to the actual situation to obtain the best extraction result.

Applications of GNSS RTK Technology to Positioning Forest Location and Measuring Microtopography

SHI Junjie, CHEN Zhongzhen, MENG Lingyu, LI Yongxiang, LI Yongning

2019,(4):  117-123.  doi:10.13466/j.cnki.lyzygl.2019.04.017

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GNSS RTK can provide real-time,high-precision positioning information and has broad application prospects in forests.We tried to measure the position of the tree using RTK in several different forest types.In addition,the tree distribution pattern and microtopography were measured on the natural forest of Larix principis-rupprechtii in Longtoushan Forest Farm.Results showed that:1) Crown density is one of the main factors affecting the availability of RTK in forests.The lower the canopy closure,the higher availability of RTK.2) Accuracy and efficiency can be improved by RTK for plot setting.There are two ways to choose,one is “straight measurement lofting”,the other is “auxiliary measurement”.3) Compared with the electronic total station,the average point error of RTK is 0.143m,which fully meets the needs of the work.4) Using ArcGis to analyze the data measured by RTK,microtopography information such as slope and aspect can be obtained.

Dynamic Monitoring of Multi-year Vegetation Coverage in Sichuan Province Based on Google Earth Engines

FENG Li, HU Wenying, LI Yingxin, ZHANG Enwei

2019,(4):  124-131.  doi:10.13466/j.cnki.lyzygl.2019.04.018

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Dynamic monitoring of vegetation coverage is an important part of studying regional ecological environment.This article uses the Google Earth Engine remote sensing big data cloud computing platform to collect the composite NDVI remote sensing images of Landsat TM/OLI in Sichuan Province from 2001-2016,and make comprehensive use of the methods of maximum synthesis,pixel binary model and trend analysis to estimate the vegetation coverage in Sichuan Province from 2001 to 2016 and analyze the changes in vegetation coverage in Sichuan Province in the past 16 years .The results show that,firstly,GEE's powerful cloud computing capability can be used to dynamically monitoring long time series in large study areas.Secondly,from 2001 to 2016,the vegetation coverage in Sichuan Province showed a relatively good overall situation and the vegetation cover change trend was relatively stable.Thirdly,the vegetation coverage in Sichuan province presents uneven spatial distribution,and generally shows a trend of gradual decrease from the edge to the center.In the past 16 years,the vegetation coverage in this region has shown a slight increase trend.In general,the vegetation coverage in Sichuan province is in good condition.

Programming Forest Management Plans Using MATLAB

HU Zhongyang, LIU Ruizhi, LIU Ping

2019,(4):  132-136.  doi:10.13466/j.cnki.lyzygl.2019.04.019

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The forest management plan is the concrete implementation for the forest management entity to manage the forest and the important guiding basis for the forest management department to supervise the forest.The traditional forest management plan has the problems of low compilation efficiency,incomplete data analysis and low utilization degree of automation.This paper,by using the MATLAB 2014a to develop the forest management plan programming,the application including data preprocessing,statistical analysis of forest resources,forest resources structure distribution map and text writing,forest working group organization and operation method designation module and so on,covers the main process of forest management plan,greatly improve the efficiency of formulating forest management plan and the ability of data analysis,provides automation processing technology support for the science formulating forest management plan.This program is easy to learn and use.It can be applied to the preparation of forest management plans by various units,as well as the preparation of county and city forest management plans and other forestry investigation plans and designs.

The Comparison on the Fire Prevention Effectiveness of Interplanting Different Broad-leave Tree Species in Pinus massnoniana Stand

CHEN Shaoshuan, CHEN Bin, CHEN Shurong

2019,(4):  137-142.  doi:10.13466/j.cnki.lyzygl.2019.04.020

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In order to explore the problem of solving the fire risk of Pinus massoniana,interplanting Altingia gracilipes,Schima superba and Phoebe bournei under the canopy of P.massoniana was tested.After 20 years of stand improvement,the biomass,undergrowth vegetation analysis,canopy structure,microclimate and fire resistance were analyzed,results show that combustible was 37.91±4.55 t/hm ² in P.massoniana,combustible were found in the mixed forests of P.massoniana with A.gracilipes,S.superba,P.bournei,which were 23.71±2.36 t/hm ²、22.54±1.85 t/hm ²、21.58±2.03 t/hm ².The undergrowth vegetation of P.massoniana were Dicranopteris dichotoma and miscellaneous bamboo,while the undergrowth vegetation of mixed forest were dominated by one or two-year-old shady herbs.The spatial structure of P.massoniana were composed of forest canopy,undergrowth vegetation and litter layer,while that of mixed forest were composed of forest canopy,broad-leaved forest canopy,undergrowth vegetation layer and litter layer.The ignition temperature of P.massoniana leaves was lower than that of broad-leaved trees,and the oil content was higher than that of broad-leaved trees.The temperature of P.massoniana were higher than those of mixed forest,and the humidity of P.massoniana were higher than those of mixed forest.When broad-leaved trees were intercropped in P.massoniana,the fire-fighting efficiency was significantly improved.The fire-fighting efficiency ranged from high to low as follows:P.massoniana and A.gracilipes 、P.massoniana and S.superba、P.massoniana and P.bournei、P.massoniana.

Spatial Accessibility of Urban Park Green Land Based on Kernel Density Estimation

YANG Wenqi, XU Yingtong, XU Ya, ZHANG Huabing

2019,(4):  143-150.  doi:10.13466/j.cnki.lyzygl.2019.04.021

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Urban park green space is one of the important indicators to measure the level of urban construction.This paper took the park green land in Dongtai urban district as the research object,adopting Kernel Density Estimation model and combining Two Step Floating Catchment Area method (2SFCA) and Buffer Analysis to study the spatial accessibility through the spatial matching degree of population and park green land.The results showed that:(1) the distribution of population and park green land in the region was unbalanced:59.61% of the population concentrated in the southwest of the urban area,and 56.36% of the park green land was distributed in the east of the city.(2) there was a remarkable spatial difference of spatial accessibility of park green land,which generally showed the characteristics of lower in the southwest and higher in the east.The accessibility grades of southwest and central urban areas were relatively low,with an index of 0.25~1.In the east of the city,the grade was high,and the accessibility index was distributed between 1.33 and 5.The accessibility of park green land in the northern development zone was moderate,and its index was 1.

Habitat Selection of Takins in Gaolinggong Mountain National Nature Reserve in Yunnan Province

CHEN Chao, HE Xiaoyang, XUE Yadong

2019,(4):  151-158.  doi:10.13466/j.cnki.lyzygl.2019.04.022

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Habitat selection is an important part of animal's adaptation to environmental behavior,habitat loss or fragmentation is currently a fundamental threat to most endangered vertebrates. At present,there are still few ecological studies on takin in gaoligong mountain area. To study the habitat selection of takin in the dulong river basin in gaoligong mountains national nature reserve in Yunnan province. The results showed that takins have the highest utilization intensity of nitrate pond,followed by mixed needle-width forest,bamboo forest,meadow,and deciduous broad-leaved forest. The distance from the nitrate pond is an important factor affecting the habitat utilization intensity of the takin,followed by altitude gradient and average altitude,the distance from road,water source and human convenience has no significant influence on the utilization intensity of the habitat. The infrared camera set in the study area took the most photos and video in the nitrate pond,followed by mixed needle-width forest,bamboo forest,meadow,and deciduous broad-leaved forest,the results of direct observation and trace observation were verified again. Therefore,the key to protect the takins in the dulong river basin lies in protecting the nitrate pond and the adjacent forest vegetation.

Vegetation Coverage Dynamics and Its Driving Factors in Inner Mongolia Based on FVC Information Entropy

WANG Jin, YAN Qingwu, TAN Xueling, ZOU Yajing

2019,(4):  159-167.  doi:10.13466/j.cnki.lyzygl.2019.04.023

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In order to explore the temporal and spatial evolution of vegetation coverage in Inner Mongolia,based on the MOD13Q1 data from 2005 to 2018,and uses Fractional Vegetation Coverage(FVC) as the main indicator to analyze the change of vegetation coverage.Using information entropy,FVC index and other methods analyze the intensity and trend of vegetation coverage in Inner Mongolia.By using GIS spatial analysis method,the influence of river,precipitation and topography on vegetation coverage is analyzed.The results show that:(1) From the time point of view,between 2005 and 2015,the intensity of vegetation coverage in Inner Mongolia is relatively stable,and the trend of change shows a slow increase trend.(2) From the perspective of space,in 2005—2018,the degree of vegetation degradation in Inner Mongolia is high in the east and low in the west,and there is obvious longitude and zonal change that the vegetation coverage from east to west is getting lower and lower.(3) Precipitation,mining areas,rivers and topography are all influencing factors of vegetation coverage change.In areas with abundant rainfall,vegetation coverage is often high;vegetation coverage in mining areas is lower than non-mine areas;river development provides good water conditions for vegetation growth.The vegetation coverage is higher in the area near the river;the different terrain has a significant impact on the vegetation coverage.The low-gradient and low-altitude areas are more suitable for the growth of vegetation than the steeper and higher elevation areas.