The impact of climate change on forest fire danger rating in China’s boreal forest

The Great Xing’an Mountains boreal forests were focused on in the northeastern China.The simulated future climate scenarios of IPCC SRES A2a and B2a for both the baseline period of 1961-1990 and the future scenario periods were downscaled by the Delta Method and the Weather Generator to produce daily weather data.After the verification with local weather and fire data,the Canadian Forest Fire Weather Index System was used to assess the forest fire weather situation under climate change in the study region.An increasing trend of fire weather severity was found over the 21st century in the study region under the both future climate change scenarios,compared to the 1961-1990 baseline period.The annual mean/maximum fire weather index was predicted to rise continuously during 2010-2099,and by the end of the 21st century it is predicted to rise by 22%-52% across much of China’s boreal forest.The significant increases were predicted in the spring from of April to June and in the summer from July to August.In the summer,the fire weather index was predicted to be higher than the current index by as much as 148% by the end of the 21st century.Under the scenarios of SRES A2a and B2a,both the chance of extremely high fire danger occurrence and the number of days of extremely high fire danger occurrence was predicted to increase in the study region.It is anticipated that the number of extremely high fire danger days would increase from 44 days in 1980s to 53-75 days by the end of the 21st century.     

Species α-diversity promotes but β-diversity restricts aboveground biomass in tropical forests,depending on stand structure and environmental factors

Forest plays a vital role in the global biogeochemical cycles through a high rate of carbon sequestration and harboring biodiversity.However,local species diversity is declining while also becoming increasingly homogenized across communities.Although effects of local biotic processes(e.g.,species α-diversity and stand structural heterogeneity) and environmental factors on aboveground biomass(AGB) have been widely tested,there is a huge knowledge gap for the effect of regional biotic processes(i....     

The mean tree mass–stand density index relationship for forest stands in China

Most traditional studies of mean tree mass (MTM)– density relationships focus on crowded stands, without considering stands characterized with canopy gaps. We developed a model to estimate MTM of closed and unclosed forest stands based on stand density index (SDI). Data were obtained from eight forest stands in China to test the generality of this model. MTM was accurately expressed in terms of SDI by combining the equations for SDI and Yoda's model, and exponents of the MTM–SDI relationship ranged from –2.23 to 1.93. Compared with density, SDI is a better predictor of MTM, regardless of the degree of canopy closure in the stands.     

Analysis of the role of forest,biomass policy legislation and other factors that may affect the future of Kenya’s forests: Use of Japanese forestry as a model

Forests are one of the most important ecosystems on earth that require careful management, conservation, and sustainable exploitation. As countries have their own guideline systems, each may learn and borrow from one another’s experience. One of such countries is Japan, which has elaborate forest policies, and rich in forest cover (67%) with its forest history dating many years back. On the other hand, Kenya, with a forest cover of just 7% and its policies demonstrating notable weaknesses, has a lot to learn from Japan. Therefore, we have attempted to do a comparative analysis of forest policies, technologies, and management practices between Kenya and Japan. Results indicate that Kenya’s forest policies do not place adequate emphasis on silvicultural practices and the establishment of forest plantations, and rarely focus on sustainable biomass utilization—factors that contributed significantly to forest growth and development in Japan. Additionally, policy legislation, revision, and implementation have not been given the deserved priority in Kenya. We conclude that Kenyan forest policy would benefit from both revision and thorough implementation. We also discuss the role of indirect factors such as economic growth and availability of nonwood-based energy sources in the future of Kenya’s forests.     

Tree and stand structure of the non-native Pinus contorta in relation to native Pinus sylvestris and Picea abies in young managed forests in boreal Sweden

Managed forest stands are typically younger and structurally less diverse than natural forests. Introduction of non-native tree species might increase the structural changes to managed forest stands, but detailed analyses of tree- and stand-structures of native and non-native managed forests are often lacking. Improved knowledge of non-native forest structure could help clarify their multiple values (e.g. habitat for native biodiversity, bioenergy opportunities). We studied the structural differences between the introduced, non-native Pinus contorta and the native Pinus sylvestris and Picea abies over young forest stand ages (13–34 years old) in managed forests in northern Sweden. We found that P. contorta stands had greater mean basal areas, tree heights, diameters at breast height, and surface area of living branches than the two native species in young stands. The surface area of dead attached branches was also greater in P. contorta than P. abies. Although this indicates greater habitat availability for branch-living organisms, it also contributes to the overall more shaded conditions in stands of P. contorta. Only one older 87 years old P. contorta stand was available, and future studies will tell how structural differences between P. contorta and native tree species develop over the full forestry cycle.     

Socio-economic factors influencing household dependence on forests and its implication for forest-based climate change interventions§

In most African countries, forest-based climate change intervention initiatives such as nationally appropriate mitigation actions (NAMAs) and national adaptation programmes of action (NAPAs) are widely accepted. This is mainly due to the fact that they are relevant in addressing multiple challenges associated with rural development, mitigation and adaptation to climate change, and sustainable forest management. However, there are concerns about the implications of strategic and practical steps taken in this context on forest-dependent communities. Thus, there is need to reconcile local socio-economic vulnerabilities and forest-based climate change intervention initiatives. In the current study, socio-economic factors influencing households’ dependence on forest resources and associated implications on climate change interventions were investigated. Proportionate stratified random sampling was used to select 366 households from forest-based rural communities in Vhembe District of South Africa. A structured questionnaire was administered to household heads in 21 villages. The Pearson’s chi-square test was used to analyse the factors that influence household dependence on forest. The effects of household socio-economic characteristics on households’ forest dependence influencing factor were determined using the binary logit model. Up to 97% of the respondents depended on the forest resources predominantly because of low costs associated with using them. It was observed that socio-economic characteristics of households such as farm husbandry skills, years of residence (53–65) in the community and age of respondents (≤38–65) significantly (P < 0.05) influenced use of the forest resources. Thus, effectiveness and sustainability of forest-based climate change intervention initiatives can be promoted if the socio-economic conditions prevailing within households in areas next to forests are improved.     

Models for predicting tree and stand development on larch plantations in Hallormsstaður,Iceland

The aim was to model the growth of Siberian larch (Larix sibirica Ledeb.) and Russian larch (Larix sukaczewii Dyl., syn. L. sibirica var. sukaczewii) plantations in Hallormsstaeur, Iceland. The field inventory was carried out in eastern Iceland in June 2006. Models were constructed for predicting dominant height, total tree height and 5-year diameter increment. Several linear and non-linear forms of models were tested in preliminary analyses to find the equations that fitted the modelled characteristics best. Due to the spatially hierarchical correlation structure of the data (stands, plots and trees), the assumption of non-correlated error terms did not hold. Therefore, a random parameter modelling approach was adopted using mixed models when the estimates obtained for the random effects were statistically significant. The variance estimates for the random effects can be further used to calibrate the models. The models generated here performed well with independent test data and were consistent with the forest growth theory. They can be used to evaluate site quality and to estimate the growth and yield of larch stands in eastern Iceland in connection with forest planning.     

Understanding forest transition in the Philippines: main farm-level factors influencing smallholder’s capacity and intention to plant native timber trees

The ‘when, where and how’ of decisions by smallholder upland farmers to plant trees as part of their use of natural, human and capital resources needs to be understood if policy support is to result in actual recovery of tree cover as part of a ‘forest transition’ trajectory. In large parts of the Philippines the turning point may be close. Data on resource access and tree planting decisions were gathered from a household survey, with a total of 148 respondents in four rural communities in Leyte Province in Central Philippines. Data were analysed using logistic regression analysis. Household-level results reveal that the outcomes of the decision-making processes primarily depend on the availability of land and access to remaining forest resources rather than socio-cultural or economic factors. The total area of land and number of parcels managed by the household plus security of land tenure through ownership was found to have a statistically significant effect on farmers’ decision to plant native timber trees. Access to surrounding natural forest is negatively associated with farmer tree planting.     

Effects of habitat type, vegetation structure, and proximity to forests on bird species richness in a forest–agricultural landscape of West Java, Indonesia

To halt biodiversity loss in the humid tropics of developing countries, it is crucial to understand the roles and effects of human-modified landscapes with fragmented forest remnants in maintaining biodiversity while fulfilling the demands of local communities and reducing poverty. To implement appropriate landscape planning for conserving biodiversity and ecosystem functioning, appropriate information is required about parameters of habitat suitability among various anthropogenic habitats with a range of distances to forests and vegetation characteristics, but such information is limited. We examined differences in avian communities between a remnant forest and four types of man-made forest (two mature plantations and two agroforests) in a forest–agricultural landscape of West Java, and we analyzed the effects of both local and landscape factors on various types of species richness in this landscape. The results from non-metric multidimensional scaling revealed avifauna in the two types of agroforest was clustered separately from that in the remnant forest, mainly because drastic declines in the abundance of forest specialists (including IUCN red-listed species) and their replacement with open-habitat generalists. The mixed-tree agroforests were colonized by 30 % of forest specialists and forest-edge species found in the remnant forest, and maintained the highest richness of species endemic to Indonesia among man-made forests, implying that some forest specialists and endemics might have adapted to ancient landscape heterogeneity. High proportion of insectivorous birds was found in the remnant forest (more than 50 %) and drastically decline in man-made forests, although the species richness of insectivores did not decline significantly in broad-leaved plantations. We concluded that protection of remnant forests should be prioritized to conserve forest bird diversity. However, as different environmental factors affected the richness values of different ecological groups, appropriate landscape design and habitat management could improve functional diversity in forest–agricultural landscapes in the tropics.     

Foliar δ15N variations with stand ages in temperate secondary forest ecosystems,Northeast China

Abstract

Natural abundance of ¹⁵N changes strongly with gradients in soil or environmental conditions across large spatial and temporal scales, but variation in δ¹⁵N with stand age at intermediate scales is poorly understood. We analyzed soil and foliar δ¹⁵N along a secondary forest chronosequence in Northeast China in mid-growing seasons 2008 and 2009, to address two questions: how does foliar δ¹⁵N vary with stand age; and are the variations driven by compositional differences in species among stands, or by consistent changes in δ¹⁵N with plant growth forms, and within species. The results showed that community-level foliar δ¹⁵N depleted as stand age increased, and these responses were remarkably consistent within three contrasting plant growth forms (herbs, shrubs, and trees), and within individual species. In spite of the three plant growth forms sharing similar responses to the stand age, tree species showed smaller variations in foliar δ¹⁵N along stand ages than herbs and shrubs. Soil δ¹⁵N also significantly depleted with increasing stand age, which may drive the variations of foliar δ¹⁵N. In addition, mycorrhizal fungi discrimination against ¹⁵N may also partly affect the patterns of foliar δ¹⁵N along stand ages. The results clearly indicate that differences in foliar δ¹⁵N among different stand ages are dominantly driven by the δ¹⁵N variations at the species levels, which reflects the variations of soil δ¹⁵N and mycorrhizal association intensity and association type, not by compositional difference in species among stands.     

A statistical analysis of spatiotemporal variations and determinant factors of forest carbon storage under China’s Natural Forest Protection Program

The Natural Forest Protection Program (NFPP) is one of the key ecological forestry programs in China. It not only facilitates the improvement of forest ecological quality in NFPP areas, but also plays a significant role in increasing the carbon storage of forest ecosystems. The program covers 17 provinces, autonomous regions, and municipalities with correspondingly diverse forest resources and environments, ecological features, engineering measures and forest management regimes, all of which affect regional carbon storage. In this study, volume of timber harvest, tending area, pest-infested forest, fire-damaged forest, reforestation, and average annual precipitation, and temperature were evaluated as factors that influence carbon storage. We developed a vector autoregression model for these seven indicators and we studied the dominant factors of carbon storage in the areas covered by NFPP. Timber harvest was the dominant factor influencing carbon storage in the Yellow and Yangtze River basins. Reforestation contributed most to carbon storage in the state-owned forest region in Xinjiang. In state-owned forest regions of Heilongjiang and Jilin Provinces, the dominant factors were forest fires and forest cultivation, respectively. For the enhancement of carbon sequestration capacity, a longer rotation period and a smaller timber harvest are recommended for the Yellow and Yangtze River basins. Trees should be planted in state-owned forests in Xinjiang. Forest fires should be prevented in state-owned forests in Heilongjiang, and greater forest tending efforts should be made in the state-owned forests in Jilin.     

Policies,Actions and Effects for China s Forestry Response to Global Climate Change

Climate change is a great concern of various countries, the public and science community, and forest plays an important role in mitigating climate change. The paper made a comprehensive analysis regarding the policy selections of China to promote forestry response to the global climate change, and elaborated the concrete actions and achievements in this regard. Policy selections include: 1) Reinforce tree planting and afforestation, increase the forested area and enhance the capacity of carbon sequestration...     

Rural household and forest: an evaluation of household’s dependency on community forest in Nepal

The aim of this paper is to analyze the level of dependency of rural households on forests, based on the economic status of the households and the property regimes of forests. The analysis of household-level dependency suggests that large numbers of rural households are benefiting regularly from their community forests. Out of three forest property regimes examined, community forests were found to be the most prominent sources for supplying forest products to local households. Analysis of the degree of forest-products dependency and the economic status of households shows that the low economic status households rely more on the community forest than the economically better-off households. In addition, a ² analysis indicates that the economic status of households affects the degree of forest-product collection activities. The results show three types of property regime with respect to forest management in Chitwan. Each regime holds its own ownership rights, which control the harvesting of forest products and provides incentives to the local households.     

Trends and responses to global change of China’s arid regions

I analyzed and elaborated the trends in and responses to global change in arid regions of China, from the perspective of nine variables, i.e., temperature, precipitation, river runoff, melting glaciers, water level of lakes, wind power and evaporation, vegetation, oases, and desertification. The climate and hydrology data I cited represent many years of observations. I conclude that, since the 1980s, the climate in arid regions of China has clearly changed with rising temperatures and precipitation in most areas. Wind power and the number of galestorm days have continuously decreased, which resulted in an improvement of humid conditions and increases in river discharge and water levels of lakes. Simultaneously, vegetation also has improved and the process of desertification has essentially been arrested. Although there are some unfavorable developments, such as decreased river flows or flow interruptions and downstream oases have suffered from degradation, these incidental cases should not distract our attention from the generally favorable trends during the middle and late 20th century. These discordant phenomena are not consequences of climate change but rather of unsuitable human activities. Despite a substantial increase in precipitation, the level of the original precipitation was so small that any increase in precipitation was still small. As a result, none of the fundamental conditions such as a scarcity of water resources and precipitation nor the landscape of drought-ridden deserts in the arid regions will change. The vulnerability of the eco-environmental system in the arid regions will not change fundamentally either in the near future. __________ Translated from Scientia Silvae Sinicae, 2008, 44(8): 124–130 [译自: 林业科学]     

Countermeasure Strategy for China’s Wood Enterprises to Meet Timber Legality Requirements

As the global forest issues and illegal logging have increasingly aroused the concerns of the international community,the US Lacey Act Amendment and the EU Timber Regulation poses requirements for the legality of timber.The paper described the background of timber legality issue,analyzed the specific requirements of the US and the EU for timber legality,and pointed out their negative impacts on China’s wood enterprises.Based on the analyses,the authors came up with the approaches that China’ s wood enterprises could adopt to meet legality requirements,and proposed the specific suggestions on how enterprises respond to the requirements for legality with an eye for the difficulties that they are confronting with.     

Distribution and development strategy for Jatropha curcas L. in Yunnan Province, Southwest China

Yunnan Province is the main distributing area of Jatropha 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 of J. 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.     

The impact of climate change on fire risk in Daxing’anling,China

Daxing'anling is a key region for forest fire prevention in China.Assessing changes in fire risk in the future under multiple climatic scenarios will contribute to our understanding of the influences of climate change for the region and provide a reference for applying adaptive measures for fire management.This study analyzed the changes in fire weather indices and the fire season under four climate scenarios(RCP2.6,RCP4.5,RCP6.0,RCP8.5)for 2021–2050 using data from five global climate models together with observation data.The results showed that the analog data could project the average state of the climate for a given period but were not effective for simulating extreme weather conditions.Compared with the baseline period(1971–2000),the period 2021–2050 was predicted to have an increase in average temperature of 2.02–2.65 °C and in annual precipitation 25.4–40.3 mm,while the fire weather index(FWI) was predicted to increase by6.2–11.2% and seasonal severity rating(SSR) by5.5–17.2%.The DMC(Duff moisture code),ISI(initial spread index),BUI(build-up index),FWI and SSR were predicted to increase significantly under scenarios RCP4.5,RCP6.0,and RCP8.5.Furthermore,days with high or higher fire danger rating were predicted to be prolonged by 3–6 days,with the change in the southern region being greater under scenarios RCP4.5,RCP6.0,and RCP8.5.     

Comments on “Plantation development: Economic analysis of forest management in Fujian Province,China”

This short article reexamines Zhang et al., 2010 (Forest Policy and Economics 2010, 12, 223–230) who concluded that forest expansion in China will continue due to the high economic benefit of forest plantations. It is suggested that their conclusion rested on data mistakes and problematic calculation, and might be misleading. A more realistic calculation is made.