In the process of coping with global warming,how to mitigate the negative effects of greenhouse effect has aroused widespread concern.Mangrove carbon sink is an important contributor to global ecosystem carbon sink,and it is also a type of carbon sink recognized by the United Nations Framework Convention on Climate Change and can be used as a clean development mechanism project,and is a breakthrough to establish China's blue carbon trading market.In practice,most of China's mangrove carbon sink trading cases are led by the government,and the problem of insufficient play of the market mechanism is still prominent.In order to give full play to the potential of mangrove carbon sink,this paper analyzed the advantages,disadvantages,opportunities and challenges of mangrove carbon sink trading,and found out that mangrove carbon sink trading possessed strong development potential,and putforward relevant suggestions on constructing the marketization path of mangrove carbon sink trading in China,so as to promote the sustainable development of mangrove carbon sink trading in China.
Firstly,based on 50 standard survey data,TWINSPAN method was used to classify 50 standard communities into different community types.Secondly,the α-diversity and β-diversity of different community types were analyzed to determine the difference of plant diversity among different community types.Finally,using redundancy analysis,plant diversity and influencing factors of different plant communities in Zengcheng Forest Farm were explored.The results showed as follows:1)The plants in Zengcheng Forest Farm included 84 families,189 genera and 270 species,which could be divided into 10 plant communities,among which the dominant communities were"Ass.Machilus chinensis+Schima superba+Lophatherum gracile","Ass.Castanopsis fissa+Heptapleurum heptaphyllum+Psychotria asiatica"and"Ass.Cunninghamia lanceolata+Schima superba+Lophatherum gracile".2)There were significant differences in α-diversity among different plant community types.The α-diversity was the most abundant in the community of"Ass.Mallotus paniculatus+Heptapleurum heptaphyllum+Blechnopsis orientalis"and the community of"Ass.Cunninghamia lanceolata+Schima superba+Lophatherum gracile",followed by the community of"Ass.Machilus chinensis+Schima superba+Lophatherum gracile",and the community of"Ass.Eucalyptus grandis x urophylla+Microstegium vimineum"was the simplest.Compared with other communities,the average p-diversity index of the community of"Ass.Machilus chinensis+Schima superba+Lophatherum gracile"was the highest,indicating the least interspecific competition and the strongest community stability.3)Stand cover and dominant tree species had significant effects on plant diversity,while stand density and altitude had significant effects on plant diversity.In summary,the comprehensive plant diversity of"Ass.Machilus chinensis+Schima superba+Lophatherum gracile"was the best.By adjusting the stand density of the dominant tree species to optimize the stand structure,the stand can be transformed in the direction of"Ass.Machilus chinensis+Schima superba+Lophatherum gracile"in forest management activities,so as to further enrich the plant diversity and enhance the system stability.
The objective of this research was to investigate different stand age classes of fine root carbon(C),nitrogen(N)and phosphorus(P)stoichiometric characteristics and their storages.Five representative soft-broadleaved forests were selected as the research objects.Fine root samples were taken at depth intervals of 0～＜20 cm and 20～40 cm soil layers in each sample-plot for indoor measurements.And the variation laws were investigated for different age classes and different soil layers for the fine root C,N,P stoichiometric characteristics and their storages in GuangXi soft-broadleaved forests.The result showed that:1)the C content of fine roots did not have a significant change with the change of forest stand ages and soil layers.The N and P contents of the fine roots differed significantly for different stand ages.While their highest values were both found in mature forest,their lowest values were found in middle-aged and pre-mature forest,respectively.2)As the forest grows older,the C/N of fine roots showed a downward trend,and the C/P and N/P normally showed a trend of first increasing and then decreasing.3)The average distribution of fine root biomass and C,N and P storage in soft broad-leaf forests in Guangxi were 7.77～12.26 t/hm2,3 324.18～4 974.21 kg/hm2,44.06～103.36 kg/hm2,7.19～13.62 kg/hm2,respectively.4)The fine root C,N,P storage and biomass of soft-broadleaved forest in Guangxi showed a decreasing trend with the deepening of soil layer and the growth of forest age.Fine root growth in soft-broadleaved forest was generally limited by nitrogen.Nitrogen input should be emphasized in each stand ages of soft-broadleaved forest.
In order to build a green and beautiful Guangdong ecological construction digital twin demonstration area,this articleused point cloud generated tree 3D modeling technology to conduct 1∶1 simulation of the core location trees within the demonstration area.Based on high-resolution stereo image data obtained from oblique photography,a high-precision and standard geographic 3D forest scene was constructed by combining 3D models of trees,buildings,and terrain.At the same time,the Internet of Things data from four intelligent comprehensive monitoring points was connected,and expressed in the virtual 3D forest scene,achieving deep integration between the virtual 3D forest scene and the real forest scene.Combined with the forest growth model,the future state of the forest was simulated,and an immersive interactive digital twin system integrating data collection,model establishment,simulation analysis,and future prediction was constructed.A relatively mature technical systemwas formed through research,providing technical demonstrations and solutions for the construction of a digital twin forestry map in Guangdong Province.
Because of the different purposes and methods of the two monitoring systems,namely the continuous forest resources inventory and forest management inventory,the data of forest resources obtained by the two monitoring systems are inconsistent.In view of this,this paper took Baoding City as an example to carry out analysis and research on the docking scheme of forest stock data between continuous forest resources inventory and forest management inventory.In order to obtain the forest stock information of each county(city and district)in Baoding city,thesubcompartment stock volume prediction model was constructed by using nonlinear index model and tree species groups.The adjustment method was adopted to realize the connection between the continuous inventory of forest resources and the monitoring value of the forest resources planning and design investigation.The results showed as follows:1)the evaluation indexes of the subcompartment stock volume prediction model developed based on tree species groups all performed well,indicating that the model had good prediction ability;2)Compared with the forest management inventory,the forest stockper unit(34.98 m3/hm2)of Baoding City monitored by the subcompartment stock volume prediction modelshowed an accuracy of 91.06％with the monitoring valueof thecontinuous forest resource inventory stock,which greatly reduced the relative error,indicating the reliability of the monitoring value of the subcompartment stock volume prediction model;3)After further adjustment of the model prediction,the connection between the continuous forest resources inventory and forest management inventory was finally realized,indicating the feasibility of the research scheme.The technical scheme studied in this paper can provide technical reference for updating the monitoring data of subcompartment stock volumein all provinces over the years and realizing"one set of data,one piece of map"in the future.
Representative populations play an innegligible role in ecological early warning and biodiversity conservation 1.The assessment of endangered species is the key basis for the priority conservation of biodiversity,analysis on the distribution pattern of representative populations from the perspective of suitable survival area.The results showed that:1)There were 10～25 species of representative populations potentially distributed in most areas of the National Park of Hainan Tropical Rainforest,accounting for 83.86％of the total area.2)The distribution of representative populations was mainly affected by altitude and vegetation type.The overall number of species distribution showd a radiation state of decreasing distribution from high altitude to low altitude,from primary forest to secondary forest and plantation.3)The construction of the National Park of Hainan Tropical Rainforest already opened up the boundary between the original protected areas and greatly promoted the interconnection of the ecosystem.However,there were still large areas of high hotspots of endangered plants that have not been included in the core protected areas.Therefore,more attention should be paid to these areas.The survival status of representative populations directly reflected the current characteristics of tropical rainforest ecosystems to a large extent.The research results can provide reference and theoretical basis for the ecological planning and biodiversity protection of the National Park of Hainan Tropical Rainforest.
The study used a combination of literature analysis and filed investigation to conduct a systematic and study ancient and famous trees of Ficus in Guangdong Province.The number,composition distribution characteristics and value of Ficus in ancient and famous trees of Guangdong province were studied.The results showed that:1)Categorized by genus,ancient trees and famous trees of Ficus have the largest number among ancient trees and famous trees in Guangdong Province,accounting for 29.13％and 14.86％,respectively.2)There are 20 species ancient trees,3 species of which are more than 1 000 a,and 4 species famous trees of Ficus.Zhanjiang city has a higher distribution of Ficus in ancient trees,accounting for 13.84％;Shaoguan city has a higher distribution of Ficus in ancient trees belonging to the first and second class,accounting for 25.23％and 16.55％,respectively;Ficus has important historical and cultural,economic,medicinal,scientific research and ecological value.
The surface temperature(LST)of Dali City was inverted using Landsat remote sensing images between 2006 and 2016.Using the morphological spatial pattern analysis(MSPA)technique,multiple linear regression and geographically weighted regression were utilized to study the coupling connection between forest landscape morphology and the temperature environment in Dali.The findings found that:1)LST in Dali City grew significantly between 2006 and 2016,and there were seasonal variations in the forest landscape and thermal environment,with the strength of several factors altering according to the season:autumn＞summer＞spring＞winter.2)The spatial morphological pattern of the forest landscape had a substantial impact on the thermal mitigation features,which were:core＞branch＞edge＞bridge＞perforation＞islet＞loop in 2006 and core＞branch＞edge＞perforation＞islet＞loop in 2016.3)The GWR model outperformed the OLS model in terms of reflecting the dynamic interaction between forest landscape and thermal environment.Throughout the urbanization process,the landscape plan may be altered in conjunction with the real circumstances to alleviate the phenomena of urban thermal environment.
According to the operational data of natural hardwood forests in Guangdong Province,using the theories of forest resource asset evaluation and research findings on the value of natural forests,this study evaluated the existing and potential natural forests at different age points.The assessment measured the various ecological product values that can be realized through resource assetization and value monetization.Against the backdrop of the current Natural Forest Protection Project,government financial subsidies were proposed as the optimal approach to realizing the ecological product value of natural forests.This subsidy scheme encompassed several aspects,including compensation for increased economic conversion value of mountain forest prices with improved ecological efficiency,compensation or funding for operational losses resulting from selective cutting or cessation of logging,and subsidies for economic losses incurred due to mature,renewable timber that cannot be harvested due to restrictions.Based on the principle of opportunity cost,scientifically fair and equitable fiscal subsidy standards for selective logging or cessation of logging were proposed.A comparison with the current implementation standards revealed a significant inadequacy in the current standards,highlighting significant room for improvement.The proposed methodology of this study was scientific and provided technical references for formulating and revising policies on fiscal compensation for ecological benefits.It also offered theoretical support for the transfer and redemption of collective and individual natural forests in the construction of nature reserves.Additionally,this research provided practical guidance for the valuation of public ecological assets in nature reserves.
The healthy development of protected areas on the Qinghai-Xizang Plateau has an important role in promoting the comprehensive construction of protected areas system with national parks as the main body.Studying the development status of protected areas and rural communities on the Qinghai-Xizang Plateau and comprehensively evaluating their coordinated development relationship are of great significance for promoting the construction of protected areas system and the revitalization of rural communities.Taking Qinghai Province as an example,we analyzed the principle of the interaction mechanism between protected areas and rural communities,and used the coupling and coordination evaluation model to carry out research on the coupling and coordination between protected areas and rural communities in five typical protected areas on the Qinghai-Xizang Plateau.The results of the study showed that:1)the construction of protected areas and the revitalization of rural communities are of equal importance;2)the coupling relationships between 5 protected areas and rural communities showed different trends;3)most of the 5 protected areas are highly coordinated with rural communities and showed a benign development trend;and a few protected areas had poor coupling and coordinated development with rural communities.Through this study,we hope to provide references for promoting the integration and development of protected areas and rural communities on the Qinghai-Xizang Plateau.
In order to explore the characteristics of ancient tree resources,the types of spatial distribution and the factors affecting their distribution characteristics,it is better to serve the urban and rural ecological environment and the construction of beautiful villages.Taking the ancient tree resources in Liaocheng City as an example,through the fishing net analysis and nuclear density analysis in ArcGIS,the spatial distribution type and distribution density of ancient tree resources were studied,and the land cover type and population density was analyzed.The influence of traditional villages and ancient tree culture on the distribution of ancient trees.The results showed that there were 687 ancient trees in Liaocheng City,including 65 first-class ancient trees,79 second-class ancient trees and 543 third-class ancient trees.The dominant species were Platycladusorientalis,Styphnolobium japonicum and Ziziphus jujuba.The tree height,DBH and crown width were concentrated in＞10.0～15.0 m,＜1.0 m,＞5.0～10.0 m,respectively.The number of normal plants accounted for 71.47％of the total number of plants,and the number of weak plants accounted for 23.73％of the total number of plants;the spatial distribution type of ancient trees was aggregated distribution,including 1 high-density area and 6 sub-density areas.The overall distribution pattern of ancient trees was"more in the south and less in the north","scattered and multi-group".Through the research and analysis,it is expected to provide reference for the management and protection of ancient trees in Liaocheng City,and provide decision-making basis for the construction of beautiful villages.
As the largest part of the natural resource system on land,forest value assessment is very important for human development.Based on the Meta analysis method of benefit transfer,this paper established a Meta regression analysis database,constructed a regression model for benefit transfer evaluation,tested the effectiveness of the model and evaluated the forest ecosystem service value of Ziwuling in Qingyang.The results showed as follows:1)The reference value of forest ecosystem service value in Ziwuling was 12.207 billion yuan,in which forest nutrient retention,water conservation,biodiversity protection and other service functions had a significant impact on forest value assessment;2)Regionalization,assessment methods and ecosystem service types of the research area are all factors affecting the value of forest ecosystem services in Ziwuling,Qingyang,and should be fully considered in the assessment;3)The error test method was used in this paper,and the results showed that the predicted value obtained by the Meta regression model had a high consistency with the actual value,and the model was effective in assessing the value of forest ecosystem services.
With the rapid development of economy and society,the construction of forest cities in China has entered a new stage of high-quality development to promote the harmonious coexistence of man and nature.In order to further implement the relevant policies of the state on continuously promoting the high-quality development of forest cities,according to the national forest city management methods and the requirements of forest city evaluation,taking Guangxi as the research object,the evaluation index system of high-quality development of forest cities was constructed from six dimensions:forest network,forest health,ecological welfare,ecological culture,organization management and regional characteristics.The entropy weight method and obstacle degree model were used to measure the high-quality development level and obstacle degree of forest cities in Guangxi.The results show that,over the past 10 years,although the development and construction of forest cities in Guangxi have achieved remarkable results,and the development level of forest networks,forest health and regional characteristics is relatively high,there are still large shortcomings in organizational management,ecological culture and ecological welfare,and there is still much room for improvement in high-quality development.It is suggested to strengthen top-level design,continuously promote the campaign of building forest cities,strengthen ecological culture construction,tap regional characteristics,and further promote the high-quality development of Guangxi forest cities in the new era.
The situation of forest fire prevention in China is severe.Analyzing and studying the spatial-temporal characteristics and susceptibility of forest fire can provide scientific basis for forest fire prevention.Based on the data of the first national forest and grassland fire risk survey,the temporal and spatial distribution characteristics of forest fire in China's 31 provinces during 2011-2020 were analyzed,and the forest fire susceptibility model in China's 31 provinces was established by using the random forest algorithm through the construction of forest fire driving factors such as fuel,meteorological conditions and terrain.The results were as follows:1)The interannual change of the frequency and burned areas of forest fire in 31 provinces showed a downward trend from 2011 to 2020.The difference was significant in different geographical regions.Forest fires in winter and spring accounted for 85.48％.2)The fuel load per unit area is the most important driving factor of forest fire susceptibility,followed by monthly mean temperature,monthly minimum relative humidity and monthly mean precipitation.3)Receiver operating characteristic curve(ROC),area under curve(AUC)and accuracy(ACC)were used to analyze the accuracy of the prediction model.The values of AUC and ACC were 0.87 and 0.84,respectively,indicating a high accuracy of the susceptibility model.4)The forest fire susceptibility in China's 31 provinces had obvious regional differences.Northeast,Southwest and East China were dominated by high and medium-high susceptibility levels,Central China and South China were dominated by medium-low susceptibility levels,and North and Northwest China were dominated by low and very low susceptibility levels.
An improved understanding of the factors affecting the optimal rotation period and the maximum land expected value of Larix principis-rupprechtii is essential under climate change scenarios and can help managers adopt adaptive forest management strategies in considering both carbon sequestration and timber production.In the current study,inventory data of 108 sample plots collected from the 6th to 8th National Forest Inventories were used to develop Faustmann models for larch plantations in northern China.The effects of timber price,carbon price,and discount rate on optimal rotation period and land expected value were then analyzed based on the resulting Faustmann model.The results showed that:1)the optimal rotation period was 27 years for larch plantations under the baseline scenario.Both the optimal rotation period and land expected value decreased with increasing carbon emission concentration;2)timber price fluctuations didn't change the optimal rotation period.The increase in carbon price can prolong the optimal rotation period.Specifically,for every 100-yuan increase in carbon sink per ton,the optimal rotation period will be extended by one year;3)the optimal rotation period and land income decreased with increasing discount rate.In the context of global climate change,it is necessary to develop optimal rotation models that consider climate factors for plantations,thereby reducing the uncertainty in future decision-making of carbon sink management.
Based on the relevant research in the field of ecotourism and analysis of the problems faced by the requirements and standardization in protected areas,the paper explained the framework and key points which the specification should focus on.According to the requirements of current policies and standardizations on the zoning of ecotourism,facility construction,recreation activities,activity management and monitoring and evaluation and other issues,the paper explained in depth that the standardization in protected areas is based on ecotourism zoning and activity control.It also stipulated corresponding content between zoning with infrastructure and service facility,and put forward relevant requirements suggestions for monitoring and management.When supplemented by supporting management measures,standardization could lead the ecotourism to a healthy development stage.
Understanding the main driving factors of forest fires and predicting the occurrence of forest fires can provide scientific basis for the prevention and management of local forest fires.Based on the historical fire data sets,meteorology,topography,human activities and combustible load data from 2011 to 2020,we built Logistic regression models and machine learning models to explore the main driving factors of forest fires in Guangxi.Additionally,the optimal model was selected to predict the probability of forest fire occurrences in the research area.The result showed that average monthly rainfall,average monthly relative humidity and the number of forest buildings were the most significant factors affecting the occurrence of forest fires in Guangxi.Both Logistic regression model and machine learning model had excellent prediction accuracy,with AUC values above 0.85.The accuracy of the machine learning model was better than Logistic regression model,and the random forest model had the highest accuracy(SAUC=0.92).The random forest model showed that the risk of forest fires was greatest in northwest,northern and southwestern regions of Guangxi.The overall results of the model were consistent with the actual situation in Guangxi and can provide a reference for forest fire prediction and forecasting in Guangxi.In the future,managers should strengthen the control of wild fire sources and prevention capabilities of extreme weather to reduce the risk of forest fires.
The Scenic Beauty Evaluation(SBE)Method is the most mature and widely used in forest landscape evaluation currently.Regarding Phyllostachysedulis in-forest landscape in Dawei Mountain National Forest Park as the study object,the author adopted SBE method to evaluate the landscape quality.Based on correlation analysis,high-correlated landscape elements was reserved.Six high-correlated elements were selected,including litter(30.4％),stand density(28.5％),withered&died bamboo(16.8％),understory uniformity(16.1％),understory height(5.2％)and average diameter at breast height(3.0％)in a descending order.Then the author built the SBE model of P.edulis in-forest landscape by using Multivariate Quantification Model with beauty value and put forward management measures with a clear aim.The research result provided theoretical basis for quality estimation and improving management technology of P.edulis in-forest landscape.
在浙江省古树名木资源普查的基础上,采用层次分析法,考虑生态经济、景观美学、社会文化、科学研究四大因素,构建古树名木价值评估体系,并按评估指标赋分标准对古树评分,参考市场价值,对全省古树名木资源综合价值进行定量评估,进而分析其总体分布情况和市域空间分布特征.研究结果表明:浙江省古树名木的综合价值为7246.05 亿元,其中,生态经济价值为787.10 亿元,景观美学价值为3548.68 亿元,社会文化价值为 1091.18 亿元,科学研究价值为 1819.09 亿元,四者之比为 1 ∶4.51 ∶1.39 ∶2.31.浙江省古树名木综合价值市域分布总体不均衡,呈西南向东北递减的分布格局,两个高价值聚集区为绍兴会稽山脉区域及丽水国家公园区域,东部平原及沿海地区为价值洼地.通过不同区域之间的横纵向比较,可以从价值的视角,揭示古树名木资源分布的特点,可为浙江省各级政府部门科学制定古树名木资源保护发展战略规划及科学决策古树名木保护资金投入提供客观依据和对策建议.
森林土壤碳库是全球生态系统碳库的重要组成部分,对人工林土壤有机碳空间分布及其影响因素进行研究,有助于了解人工林土壤碳汇动态变化规律.以河南省国有登封林场栓皮栎人工林为研究对象,采用系统抽样法在林地内设置 186 个样地(10 m×10 m),应用地统计学方法分析了土壤有机碳空间分布特征,构建并使用结构方程模型识别出土壤有机碳主要影响因素.结果表明,栓皮栎人工林土壤有机碳含量平均值为 18.59 g/kg,其空间分布呈斑块状,高低值区分布较为分散;而平均土壤有机碳密度为 2.47 kg/m2,其空间分布特征与土壤有机碳含量表现出高度一致性,但整体分布更均匀.相关分析结果表明,土壤有机碳含量和密度与胸径、树高等林分因子,与土壤全氮、土壤速效磷等土壤因子呈显著正相关关系(P＜0.05);结构方程结果表明,土壤有机碳含量和土壤有机碳密度受土壤化学性质影响均最大,其中土壤全氮的贡献度最高.研究对于揭示人工林土壤碳汇形成机制,制定土壤碳汇调控技术措施有一定的参考价值.
