National assessment of the evolution of forest fragmentation in Mexico

This paper presents assessments of the fragmentation of the temperate and tropical forests in Mexico at the national level for two dates 1993 and 2002. The study was based on land use and vegetation cover data sets scale 1:250,000. Two broad forest types (Temperate Forests and Tropical Forests) and five more specific forest types (Broadleaf Forests, and Coniferous Forests; Tropical Dry Deciduous Forests, Tropical Sub-evergreen Forests, and Tropical Evergreen Forests) were defined to conduct the analyses. FragStats 3.3 was used to estimate nine metrics of the spatial pattern of the forests for each forest type and date considered. The results indicate that the land cover transitions that have occurred between 1993 and 2002 have resulted in more isolated forest patches with simpler shapes in both the Temperate and Tropical Forests. The remaining Tropical Forest patches have become smaller and more numerous. In contrast, the remaining Temperate Forest patches are fewer and on average larger. Of the more specific forest types defined in this study, the Broadleaf Forests have the highest indicators of fragmentation. However these forests are usually embedded or adjacent to Coniferous Forests. Of more concern for conservation purposes are the high values of fragmentation metrics found for the Tropical Evergreen Forests and Tropical Dry Deciduous Forests, because these forest types are usually surrounded by non-forest land covers or anthropogenic land uses.     

基于农户调查的退耕还林若干问题研究(Ⅰ)——以河北省丰宁县为例

通过对丰宁县9个乡镇25个村200个农户的问卷调查,对退耕还林过程中存在的一些问题进行了研究.结果表明,大部分农户对于国家的退耕还林政策还不是十分了解,教育程度越高的农户对政策了解程度也越高;大多数农户对于国家的退耕还林政策持支持态度,对于退耕还林政策的执行较为满意;多数农户认为,退耕还林后环境条件有了较为明显的改善;但是,多数农户认为国家的退耕还林补助期限太短,应该适当延长.同时,部分农户表示,补助期满后将会复耕.建议加大退耕还林政策宣传力度,提高农民对于退耕还林政策的了解程度,同时在后续政策的制定中,适当调整补助政策,使退耕还林工程得以长期、有序、健康的发展.     

Factors influencing the loss of forest cover in bangladesh: An analysis from socioeconomic and demographic perspectives

Some studies have attributed forest shrinkage to population growth, economic development, conversion of forest land to agricultural use and harvesting of trees for timber and fuelwood. But the statistical support for these hypotheses is not strong. This paper attempts to test the above hypotheses statistically in the case of Bangladesh. Factor analysis extracted 4 important factors—(a) exploitation of forests for timber, fuelwood, tea, and shrimp production, (b) demographic pressure in agriculture, (c) economic development, and (d) expansion of crop lands—as causes of deforestation. The statistical test supports the hypotheses that the exploitation of forests for timber, fuelwood, tea and shrimp production, and conversion of forests to crop lands have a negative influence on forest cover. Economic development and demographic pressure in agriculture are also negatively correlated with forest cover. Results of regression analysis show the conversion of forests to agricultural land is the most important cause of deforestation. Other important causes, in order of their relative importance, are the relative price of forest products, population growth, economic development, demographic pressure in agriculture, increasing production of shrimps, export of tea and shrimps, increasing production of timber and fuelwood, and expansion of tea lands. The statistical tests support the above relationships.     

基于农户调查的退耕还林若干问题研究(Ⅱ)——以河北省丰宁县为例

采用农户调查的方法对丰宁县退耕还林情况进行了调查,分析了退耕还林过程中存在的问题。研究结果表明:退耕还林过程中林种与树种的选择主要由政府部门确定,农户的参与程度较低;大部分地区退耕造林造林成活率较高,经补植成活率可以达到75%以上;大多数农户未采取任何抚育管理措施;放牧是影响造林成活率的一个重要的因素;大部分农户没有在林内进行间作。今后的工作重点是加强栽后的抚育管理工作,重点解决放牧与林木保护之间的矛盾,维持造林成果,同时,在立地条件适宜的退耕地中,可适当鼓励农户进行间作。     

Factors influencing the formation of unburned forest islands within the perimeter of a large forest fire

Large forest fires have recently increased in frequency and severity in many ecosystems. Due to the heterogeneity in fuels, weather and topography, these large fires tend to form unburned islands of vegetation. This study focuses on a large forest fire that occurred in north-eastern Spain in 1998, which left large areas of unburned vegetation within its perimeter. Based on a satellite post-fire severity map we searched for the relative influence of biotic and abiotic factors leading to unburned island formation. We divided the area of the fire into individual units we called “slopes” which were meant to separate the differential microclimatic effects of contrasted aspects. The number of unburned islands and their areas were related to 12 variables that influence their formation (i.e. land cover composition, aspect, steepness, forest structure, two landscape indices and weather variables). We hypothesized that unburned vegetation islands would concentrate on northern aspects, in less flammable forests (i.e. broadleaf species) and higher fragmentation to interrupt the advance of fire. While north and western aspects did have a higher presence of unburned vegetation islands, our study suggests greater presence of islands in slopes that are larger (i.e. more continuous areas with relatively homogeneous aspect), with greater proportions of forest cover, with higher wood volumes and with lower proportions of broadleaf species. Climate also played a role, with relative humidity and wind speed positively and negatively correlated to island formation, respectively. Unburned vegetation was more frequent on slopes with lower diversity of land covers and higher dominance of one land cover in the slope. Since slopes with only one land cover (i.e. forests) had more islands than slopes with multiple cover types, we infer that under severe meteorological conditions, fragmented forests can be more affected by wind and by water stress, thus burning more readily than forests that are protected from this edge phenomenon. These results would reinforce forest management strategies that avoid linear features (fire-lines and fire-breaks), to enhance fuel treatments that focus on areas and minimize fragmentation.     

Prospects of forest road infrastructure development in northwest Russia with proven Nordic solutions

This paper analyses the situation with forest roads in Russia in the context of harvesting, transportation, forest management and forest fire prevention. Russia harvests less than 30% of its allowable harvest potential. Forest fires burn volumes which are equal to half of the annual harvest. One reason is the insufficient density and quality of forest roads. The average density of roads is less than 1.5 m/ha, which is one-tenth of that in Nordic countries. We argue that better access to the forests, utilizing the technology transfer of the proven Nordic forest road solutions (NFRS) under local conditions, might have important effects on the strategy-making processes in forest infrastructure development in northwest Russia. For this purpose, A'WOT analysis is proposed to identify the related strategies and assign priorities to those strategies. According to this study undertaken in Karelia, where NFRS were introduced over 10 years ago, the top priorities regarding the relevant threats are the lack of legal framework under forest land leasing and the low profitability of forestry. The results indicate that the NFRS are viewed positively for the Russian conditions. The forest road market has virtually unlimited opportunities for growth. Together with a favourable policy in terms of national and regional development programmes it can support forest infrastructure development. Forest fire prevention, multiple uses of woodlands, and different environmental service markets are seen as potential opportunities for NFRS. However, the results also indicate that there is substantial uncertainty and scepticism concerning how such markets would be of benefit to leaseholders who would like to adopt intensive forestry.     

城市森林与城市森林游憩

城市森林游憩可分为两类,即日常性游憩与专题性游憩;提出要发展郊区城市森林以及建设郊野游憩带的概念,为城市居民提供更能亲近自然的游憩活动机会;必须通过合理规划、建设与调整,建设森林型的生态廊道、公园路,为城市内部与郊野的城市森林建立有机联系;指出把公众参与、全社会的认同与协调作为实现城市森林可持续发展目标的主要内容。       

集体林地公益林生态补偿资金分配方法研究

以模拟的王村1组2015年核算公益林户补偿金为研究对象,通过建立林地生态价值评分标准,计算各小班生态价值得分,据此分配整个公益林补偿金,得出科学合理分配集体林地公益林补偿金的一种方法。     

Collective Forest Tenure Reform in Nature Reserves in China:Problems and Countermeasures

Collective forest tenure reform is now carried out throughout China with the aim to clarify the property,increase forest farmers' income and motivate the development of forestry.But the collective forest tenure reform in nature reserves comes to a dilemma.The current implemented laws and regulations provide that forests and trees in nature reserves shall be under strict protection,while the forest farmers hope to improve their livelihood in the reform.The paper discussed the problems encountered in the c...     

浙江湖州低缓坡毛竹林早出春笋鞭笋“两笋模式”经营关键技术

竹产业是事关民生与生态建设的重要产业之一。为促进竹产业的可持续发展,切实增加竹农收入,在毛竹林分类经营的同时,积极探索笋用林高效可持续经营模式,即毛竹林早出春笋、鞭笋“两笋模式”,并取得了阶段性成效。文章从林地和林分选择、竹林管理、覆盖施肥以及笋期管理等方面详细介绍了毛竹林经营“两笋模式”的关键技术,以期为高效、可持续经营毛竹林提供技术支撑。     

Recovery of boreal forest structures near abandoned villages in Western White Sea Karelia,Russia

Regeneration of natural forest structures and dead wood has a key role in the long-term maintenance of biodiversity in most parts of the boreal zone. In order to obtain benchmarks for practical dead wood management rapidly, we utilised unintended historical experiments in land use by studying the recovery of forests surrounding abandoned villages along 2.5-km transects in NW Russia. The signs of past human forest use declined as a function of distance from villages. We found that the closest forests were 130 yr old or younger and contained very few elements typical of natural forests. Forests at a distance of between 1 and 1.5 km were older than 150 yr but showed marks of selective cuttings and had a less complete continuum of dead wood than forests that were 2–2.5 km from the villages. The most remote stands, which were generally older than 200 yr, predominantly had no signs of past forest use and had the most diverse dead wood composition. Our study shows that full recovery of the dead wood continuum in middle boreal forests is a slow process and also that less intensive past forest use can have a significant effect on the dead wood continuum.     

Impacts of participatory forest management on forest conditions: Evidences from Gebradima Forest,southwest Ethiopia

ABSTRACT

This study examines a participatory forest management program and its impacts on forest conditions in Gebradima Forest, southwest Ethiopia. Vegetation data were collected from both participatory forest management (PFM) and nonparticipatory forest management (non-PFM) forest blocks. A total of 54 plots (27 from each forest block) measuring 20 m × 20 m were employed to collect species composition and structural data. Results indicated that a total of 51 different woody plant species (49 at PFM and 43 at non-PFM blocks), representing 31 families were recorded, with 41 species were shared for both forest sites. Species diversity and evenness were higher in the forest with PFM (H´ = 3.29, E = .85) compared to the forest without PFM (H´ = 2.97, E = .79). The overall mean values of tree/shrub and seedling density per hectare, diameter class (≤ 20 cm) were also significantly (p < .05) higher in PFM forest than non-PFM forests. However, no significant variations were observed in sapling density per hectare and basal area between the two studied forest blocks. It can be concluded that PFM had a positive effect on forest conditions compared with a similar forest without PFM. Hence, it is important to scaling up PFM in neighboring forests.     

Does communal forest intervention management enhance forest benefits of smallholder farmers? Evidence from Hugumbirda forest,Tigray, Ethiopia

Forest rehabilitation activities within centrally controlled state-owned forests in Ethiopia could not deliver communities with increased income. A study aiming to assess the benefits of forests for smallholder farmers whose land falls close to the state forest was conducted in Hugumbirda and Endedo kebele, two villages located adjacent to the Hugumbirda forest. Semi-structured questionnaires were used to collect data from 251 randomly selected households living near or adjacent to the state forest. A logit model was used to analyze factors affecting household’s willingness to scale up forests at the communal level. Most of the respondents living near or adjacent to the national forest were found to be dependent on the forest for fuelwood and therefore energy, timber products, and farming equipment. Furthermore, households were found to perceive that communal intervention management is a significant factor in attempts to further scale up forests. Scale-up of forests at the community was one option to enhance the vegetation cover and therefore increase primary production by promoting infiltration and decrease evaporation and runoff water. Finally farmers have suggested the state forest should be devolved to the community to improve the current level of forest contributions to the livelihood of smallholder farmers.     

涉及林农权益保护有关问题的探讨

笔者就林业生态林补偿、商品林采伐和林地流转等3个涉及林农权益问题进行了调查与分析,提出了解决问题的建议与办法。     

Exploring the future use of forests: perceptions from non-industrial private forest owners in Finland

The transformation of the forest sector toward a bioeconomy calls for finding new sources of competitive advantage for the whole sector to retain its future viability. Non-industrial private forest owners are an important group of actors in the Finnish forest-based sector, as they supply 80% of industrial roundwood and control numerous other tangible and intangible forest-based ecosystem services. Our study analyzes forest owner views on the future use of forests in Finland, their perceptions on the evolving sectorial interlinkages and the position of the forest sector now and in the future bioeconomy. The data were collected in two phases: through telephone interviews of forest owners (n?=?278) and four focus group (FG) discussions (n?=?17), and were analyzed both qualitatively and quantitatively. The interviews showed that forest owners consider the highest potential for strengthening the sector toward bioeconomy to come from collaboration with energy and construction businesses. During the FG phase, we identified new possibilities founded on forest-based recreational services, cooperation with nature-based tourism and in increasing value-added wood products. In total, forest owners as a high-involvement group emphasized future value creation to be based upon forest ecosystem services and in diversifying the utilization of forests beyond the dominant raw material-driven mindset.     

Improving the estimate of forest biomass carbon storage by combining two forest inventory systems

Quantifying forest carbon storage and its spatial distribution at regional scales is critical for the creation of greenhouse gases inventories, the evaluation of forest services and carbon-oriented forest management. The plot-based forest inventory (PBFI) and stand-based forest inventory (SBFI) collect extensive information on trees and stands respectively, and together, provide an opportunity to improve the regional estimates of forest carbon. In this study, we applied the SBFI to overcome the spatial extent limits of the PBFI in neighboring plots and improve the regional carbon estimation. We found that the forests in Sichuan Province reserved a total of 624.2?Tg?C in biomass and featured a large spatial heterogeneity, with high values in natural forests and low values in plantations. We found that the solo use of PBFI derived a slightly higher (46.63?Mg?C/ha) estimation on average compared with the integrated method (43.6?Mg?C/ha). However, when considering the spatial distribution, the PBFI generated an overestimation of young forests located between 3000and 4000?m in elevation, and an underestimation in mature forests. The spatially explicit biomass carbon estimation could be helpful in guiding regional forest management and biodiversity conservation.     

Propensity of farmers to conserve forest within REDD + projects in areas affected by armed-conflict

The implementation of carbon-storage efforts in countries experiencing armed conflicts or confronting illegal activities (such as illicit crop cultivation) will permit additional tropical forests to be protected for climate change mitigation. Yet, despite these potential gains, the appropriate design and application of forest conservation and climate change mitigation approaches such as the mechanism for Reducing Emissions from Deforestation and Forest Degradation (REDD +) in such contexts remain little studied. Unanswered questions relate to the propensity of farmers in conflict affected areas to conserve forests for climate change mitigation. Such questions include, for what reasons and under what circumstances would such farmer participate in climate change mitigation activities? In this paper we address these questions by developing an econometric Logit model to understand factors influencing the propensity to conserve forest of farmers from 14 villages in Colombia. These villages are located in a region recognized as a stronghold of guerrilla insurgencies and as the center for illegal crop cultivation. The region was selected as it is also the proposed target area for piloting Colombian government REDD + activities. A household survey (n = 90) showed that four explanatory variables are significantly related to the ‘propensity to conserve forest’. ‘Harvest of non-timber forest products’ (specifically bush meat) positively influences a farmer's propensity to conserve forest. In contrast, higher ‘percentage of forest area’, ‘deforestation for (the production of) subsistence crops’ and ‘harvest of wood product’, each have a negative influence. Overall, results show an already high propensity to conserve forest among farmers (70% of respondents) and indicate their growing propensity toward the conservation of primary forest and management of degraded lands and secondary forest. These results might be attributable to efforts undertaken to reduce the causes of armed-conflicts and ecosystem deterioration, such as enhancement of land tenure security and farmer associations' rules to reduce deforestation. They might also be linked to communities' positive attitudes toward water resources conservation. We conclude that most farmers will not oppose forest conservation as long as it is compatible with their respective livelihood priorities.     

辽宁省集体林林权制度改革林农行为问题的调查分析

对辽宁省集体林林权改革中林农行为进行了调查与分析,结果表明:有82.00%的林农在林权改革中获得了林地,86.76%的林农对林权改革满意,84.84%的农户有投资的意愿,进行林下多种经营的林农户数有了显著提高,增长了2倍。影响林农进行林业生产投资的主要因素是:缺乏资金,担心政策变化,采伐限额限制木材生产。筹措资金、保持政策的连续性、科学经营森林(合理分配采伐指标)是巩固集体林权改革成果的基本保障。     

Forested land-cover patterns and trends over changing forest management eras in the Siberian Baikal region

Remote sensing observations over areas of the former Soviet Union suggest that there may be important ongoing influences on forested landscapes resulting from divergent land use and forest management associated with the Soviet versus post-Soviet eras. As the Russian Federation implements its new Forest Code and associated regulations, knowledge of existing forest patterns and trends, plus the development of methods with which to understand the landscape-level influence of different forest management strategies is increasingly important. We developed spatial–temporal models and projections of forest patterns and trends over Soviet and early post-Soviet forest management eras for a study site in the Lake Baikal region in southern Siberia. We used Landsat-derived land-cover data, logistic regressions, and Markov and cellular automata methods (CA–Markov) to characterize patterns and trends 1975–1989 and 1990–2001, and to develop predictive scenarios through 2013. Relationships of forest types (Conifer, Mixed, Deciduous) and Agriculture to other explanatory environmental variables indicated mostly consistent forest–environment relationships, but some different spatial relationships between eras were found for Cut and Regeneration disturbance types. Landscape proportional trends showed greater differences between eras. Cut proportions observed via Landsat in 2001 were approximately 74% lower, and the area of Conifer observed was approximately 14% higher, than modeled proportions predicted for 2001 using 1975–1989 Soviet era transition rates. The proportion of Cut projected for 2013 was about 80% lower when based on early post-Soviet era probabilities. Overall, modeled results indicate that should early post-Soviet trends continue, low rates of logging, some agricultural abandonment, re-growing forests especially near access routes, increases in deciduous cover, along with continued or increased fire events in mixed and conifer forests will define the landscape. Should forest management change, for example to Soviet era rates and patterns of harvest, different outcomes are projected. More broadly, results highlight the real and prospective effects that divergent management strategies can have on forested landscapes, and demonstrate that land-cover data combined with emerging spatial–temporal modeling methods provide an approach to understand and project the complex and ongoing influences associated with changing forest management at landscape scales.