Human impact on population structure and fruit production of the socio-economically important tree Lannea microcarpa in Burkina Faso

Non-timber forest products (NTFPs) are of high socio-economic value for rural people in West Africa. Main factors determining the status of the populations of socio-economically important tree species providing those NTFPs are human activities. This study assesses the impact of human population density, land use, and NTFP-harvesting (pruning and debarking) on population structure and fruit production of the socio-economically important tree Lannea microcarpa that is normally conserved by farmers on fields. We compared L. microcarpa stands of protected sites with those of their surrounding communal sites in two differently populated areas in Burkina Faso. Our results reveal an opposed land use impact on the population structure of L. microcarpa in the two areas. In the highly populated area, the species population was more stable in the protected site than in the communal site, while the opposite was observed for the less populated area. Trees of the communal sites bore more fruits than trees of the protected sites. Debarking and pruning had a negative impact on fruit production of the species. We conclude that low intensity of human impact is beneficial for the species and that indirect human impact facilitates fruit production of L. microcarpa. In contrast, in the densely populated area, human impact has reached an intensity that negatively affects the populations of L. microcarpa. While the extent of protecting L. microcarpa on fields still seems to be enough to guarantee the persistence of this important species in the less populated area, it is no longer sufficient in the densely populated area.     

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.     

湖南省乡村公路发展现状及对策研究

乡村公路是公路网的重要组成部分，是保障农村社会经济发展最重要的基础设施之一，是农村地区最主要甚至是一些地区唯一的运输通道。文章在分析当前湖南省乡村公路的发展现状及存在问题的基础上，从养护、资金、客运和规划等方面提出乡村公路发展的一些对策建议。     

Biological activity of soils under rubber trees (Hevea brasiliensis) affected by trunk phloem necrosis

Trunk phloem necrosis (TPN) is currently one of the most economically important diseases of the rubber tree (Hevea brasiliensis). Investigations of the aetiology of the disorder have failed to identify any biotic causal agents but a multidisciplinary study has recently suggested that the disease may be caused by a combination of exogenous and endogenous stresses. These stresses can affect plant physiology and may also have an impact on soil biology and soil biochemistry. In this study, macrofauna diversity and soil enzyme activities were compared for the soils under trees affected by TPN and under healthy trees. Principal component analysis revealed associations between TPN and macrofauna diversity and soil enzyme activities. Groups of ants and termites were associated with the soil under healthy and trees affected by TPN respectively. Polysaccharidase (cellulase, xylanase and, particularly, amylase) activities were lower in the soil under trees affected by TPN whereas N‐acetylglucosaminidase activity was higher. These findings suggested that termite density and N‐acetylglucosaminidase activity are useful indicators of TPN, while lower values of polysaccharidases activities are the consequence of this disease. The impact of TPN on soil ecosystem was discussed.     

Monitoring Growth Trials

The forestry industry predominantly depends on privately-owned forests which are foreign-owned, capital intensive and export oriented. The man-made forests cover 102 000 ha, about 6% of the total area of Swaziland. The two largest plantations, Usutu and Peak Timbers, account for 71% of the total plantation area in the Kingdom.

Pines and eucalypts are the two main genera planted for pulp, mining timber, sawtimber and droppers. There are nine companies engaged in the processing of wood into various products.

The land classified as marginal in Swaziland on account of low rainfall (less than 600 mm) occurs in low-veld, with characteristic tree species like Acacia nigrescens (umkhaya), Acacia tortilis (sitfwetfwe) and a fruit tree Sclerocarya caffra (umganu). In this region, plantation agriculture of citrus trees and sugar cane is only possible under irrigation. In terms of low inherent soil fertility in the highveld, plantation forests are grown on acidic granite and gneiss and also on land whose average gradient is more than 15%. Biotically induced marginal land occurs because of man and his activities: overstocking of livestock, uncontrolled burning of the veld during the dry winter, inadequate soil husbandry, increase in demand for various forest products and infrastructural development.

Low rainfall between 1974 and 1976 killed Eucalyptus grandis and Pinus taeda and reduced the growth rate of Pinus patula. Most of the forest sites in Swaziland are marginal land on account of granite and gneiss-derived soils of low pH, i.e., 4,5 to 5. Between 1981 and 1982, 27 t of different fertilisers were used in order to achieve an MAI of at least 17 m³/ha/a of utilisable material for Pinus patula on a 22 year rotation.

Usutu Forest and Peak Timbers Plantations have progressively contributed to the economy of Swaziland since the 1940s. In 1978, forest plantations and forestry oriented industries contributed about 24% of the total export earnings. During 1980, 95% of the unbleached kraft pulp was sold outside Southern Africa, while 3,1% of the total forest products was consumed in Swaziland. The forest plantations have improved the general infrastructure, including roads and educational and recreational facilities in the areas where they occur.

Resettlement schemes have also been undertaken among the displaced people.

The interest of the Swaziland Government lies chiefly in regulation and control of the forest sector, to optimise the existing resources to the benefit of the Swazi people, mainly for economic use of the land and water resources and encouraging national participation, at both wage employment and management levels, as well as implementing forest legislation.

Plantation forest activities have, however, several disadvantages to be cited: They are land extensive and therefore tend to encroach on land used for communal grazing and hunting, bee collecting and firewood and fruit gathering, all of which are difficult to quantify in monetary terms. The Euro-American philosophy of replacing open communal land with fenced boundaries marked by cairns, with penalties on contravention, cannot be readily accepted.

The forest product needs for the rural community come from the Swazi Nation Land, covering 65% of the total area of Swaziland. The biotic factors have much reduced the original area of vegetation cover which has resulted in the use of non-conventional material like cow dung, maize stalks, leaves of Aloe marlothii (inhlaba) and tall grass for fuel. The commercial forests are located far from the population centres, thus making transportation of the forest waste an uneconomic venture.

The Forestry Section, under the Ministry of Agriculture and Co-operatives, is working in close co-operation with the Rural Development Area (R.D.A.) programme to raise the general standard of living in the rural areas by establishing woodlots. In the current five-year National Development Plan, the Government plans to establish 13 000 ha of woodlots, carry out an indigenous forest inventory, implement forest legislation and train forestry personnel at all levels.

With the assistance of R.D.A. Project Managers, the donga-ridden areas on the biotically induced marginal land are fenced off and then planted with suitable tree species.

Black wattle, Acacia mearnsii, introduced in Swaziland at the beginning of this century, is predomminantly used for bark production. It covers 5 000 ha on Swazi Nation Land and 2 500 ha on Title Deed Land. Lack of proper management of black wattle has turned it into “jungles” in the Highveld, where land is not used for agricultural production. The yield of wet wattle bark is low on Title Deed Land, i.e. 15 to 20 t/ha. The bark is marketed on a basic bark quota system managed by a wattle growers committee of Pietermaritzburg. Wattle growers of Swaziland have now formed a cooperative to enable them to transport the bark economically.

The spread of black wattle has checked the formation of dongas in biotically induced marginal areas, but at the same time there is a general resentment among the rural community who believe it is eating up their grazing land. The public believe also that eucalypts are responsible for the drying up of streams and encouraging lightning in the rural areas.

Indigenous Acacia species are drought resistant, more favoured as fuelwood, but their MAI is very low and their seed is very difficult to collect and extract. Even when using exotic tree species in establishing woodlots, proper provenances are not easy to obtain.

Agro-forestry is being undertaken particularly in RDA's where individual farmers get tree seedlings from the forestry nurseries and plant them among agricultural crops.     

Role of non-wood forest products for local livelihoods in countries with transition and market economies: case studies in Ukraine and Sweden

Abstract

The role of non-wood forest products (NWFPs) in local economies differ in time and space. We analysed Ukrainian and Swedish national policies and management rules related to the use of NWFPs, and described how different forest stakeholders utilised NWFPs in rural areas in Ukraine and Sweden. In total we interviewed 114 local forest stakeholders in one rural region's settlements in both countries. The topics for the field study were (1) the reasons and amounts of NWFPs harvested by different forest user categories; (2) traditional practices of NWFP use, including harvesting methods and (3) how these practices have changed over the past decades. At the national level, both countries allowed the utilisation of most NWFPs, did not regulate the use, and did not include NWFPs into forest management plans. In both case studies, historical use of NWFPs was intensive. This use remained important in Ukraine, but not in Sweden. Due to difficult economic transition in Ukraine, use of NWFPs by locals has increased. While hunting as a tradition was more popular in the Swedish case study, recreational use of forest was popular in both case studies. Finally, we discuss the role of NWFPs in countries with transition and market economies, and the extent to which the countries support sustainable use of NWFPs.     

亚洲象栖息地恢复与食源地建设

在西双版纳国家级自然保护区亚洲象集中活动的栖息地范围,选择莲花塘、小田坝和冷山河3个区域实施栖息地恢复、食源地和硝塘建设等项目,扩大和改善亚洲象栖息地,丰富食物源,引导外溢象群逐步回归保护区内。文中介绍亚洲象种群数量变化情况,栖息地与食源地以及人象冲突现状,阐述项目建设必要性、目标以及建设方案。提出降低森林郁闭度、食源地建设、硝塘建设、监控视频安装等技术措施,并进行了环境、社会和经济影响评价。     

Evolution of Portuguese community forests and their governance based on new institutional economics

Forest governance is under reorganisation in many European countries, because of the changes in property and forest tenure rights. Portuguese community-based forestry is an interesting research subject from a New Institutional Economics perspective. Community forests (an important part of community lands known as baldios) cover half a million hectares in the north and the centre of the country and are owned by local communities. Their average size of over 400 hectares and diversity of resources underscore their value, and their management contributes to rural development. Recent laws intend for the complete transfer of their tenure rights to communities and local authorities. In this study, we analysed the transformational processes of Portuguese community-based forestry. To structure this analysis and shed light on forest management-related problems, we followed the 'four-level institutional analysis' developed by Williamson. Particular attention was paid to the first three levels. The first concerned social practice and informal rules. We are describing the history of baldios, their use by rural populations, and the subsequent occupation by the State for afforestation. The second level addressed the institutional environment and formal rules. Here, we focused on the recognition of baldio community properties and their legal framework development. The third level addressed management and the interaction of actors in transaction cost savings. Here, we examined the current community-based management models and future trends. In our analysis, we identified the causes underlying baldio management problems at different levels, which highlight the importance of new governance models and economic activities. The analysis showed that overall, the Portuguese community forest governance is a flexible structure capable of adapting to political and demographic changes and offering valuable support for the development of rural areas in the north and centre of the country. Additional empirical research is needed to improve knowledge on the impact of institutions on the management of community forests, both nationally and internationally.

     

杨树虫害动态与防治对策

山杨楔天牛(Saperda carcharias L.)及杨干隐喙象(Cryptorrhynchus lapathi L.)是欧洲大陆各国最严重的蛀干害虫,杨树人工林90%左右的损失是这类害虫造成的。多品种小面积、团状或带状混植及推行短轮伐期作业,把单功能的防护林改造成经营防护型,是有效防治这类害虫的根本对策。     

The agroforest alternative to Imperata grasslands: when smallholder agriculture and forestry reach sustainability

Basic prerequisites for sustainable reforestation of Imperata grasslands in Southeast Asia are presented. A theoretical forest is designed according to these prerequisites. Composed of basic units managed by local smallholders, the forest is composed of two sets of commercial tree species suited to local conditions, one set providing regular cash income and the other providing seasonal or irregular cash income. Such composition ensures economic and ecological viability of the forest in the long run, provided that clear tenurial right on the basic units are recognized. Guidelines for a transition from Imperata grasslands to forest are presented, underlining the importance of relying on natural succession processes. The theoretical forest is identified as an agroforest, a diverse forest rebuilt and managed by farmers, providing forest and agricultural products for both cash income and household consumption. Agroforests have been developed for decades by indigenous farmers in some regions of Southeast Asia. Examples from Indonesia are presented to support the theoretical analysis. They show that the agroforest alternative is a valuable unifying concept for reforestation of Imperata grasslands, for a sustainable upland agriculture, and more generally for an equitable environmentally and economically sound development of rural areas in the humid tropics. sound development of rural areas in the humid tropics.     

Fire history of coniferous riparian forests in the Sierra Nevada

Fire is an important ecological process in many western U.S. coniferous forests, yet high fuel loads, rural home construction and other factors have encouraged the suppression of most wildfires. Using mechanical thinning and prescribed burning, land managers often try to reduce fuels in strategic areas with the highest fuel loads. Riparian forests, however, are often designated as areas where only limited management action can take place within a fixed-width zone. These highly productive forests have developed heavy fuel loads capable of supporting stand-replacing crown fires that can alter wildlife habitat and ecosystem function, and contribute to stream channel erosion. Objectives of this study were to determine whether adjacent coniferous riparian and upland forests burned historically with different frequencies and seasonalities, and whether these relationships varied by forest, site, and stream characteristics. We measured dendrochronological fire records in adjacent riparian and upland areas across a variety of forest, site and stream conditions at 36 sites in three sampling areas in the northern Sierra Nevada.     

Gendered business activities in family farm forestry: From round wood delivery to health service

Abstract

The development of non-wood forest products and services has been put forward as a means for business diversification and development of rural areas. However, the well-documented male dominance in traditional family farm forestry (FFF) is considered to restrain women's involvement in forestry activities, and thus hamper new enterprising businesses. Given the gender structure in traditional forestry, it is hypothesised that women are more likely to engage in less traditional activities than men. Through a cluster analysis of data from the Swedish Farmers Association's member survey, typical combinations of forest-related business activities were identified. The representation of women and men as operational managers within each activity was assessed. Results show that traditional forestry is the main task for both male and female FFF owners, however, women engage more often than men in service-oriented business activities. The main conclusion is that the prevailing pattern on the labour market, with women predominately within service and care professions, seems to be reproduced within FFF businesses. The results are further discussed in relation to owner types and possible impact on FFF restructuring and rural development.     

Income and labour productivity of collection and use of indigenous fruit tree products in Zimbabwe

Rural people in Africa periodically rely on wild fruits to supplement their diet and to generate cash income. However, scientific evidence on the economics of using indigenous fruit tree (IFT) products is scarce. The objective of the study was to fill in some of the gaps for which farm-household surveys were conducted in Zimbabwe during 1999–2000. Gross margins and returns to labour in collection, use and sale of products of Uapaca kirkiana (Muell. Arg., Wild Loquat), Strychnos sp. (S. cocculoides (Baker) and S. spinosa (Lam.), Monkey Orange) and Parinari curatellifolia (Planch. ex. Benth., Fever Tree) were compared with other farming activities. A random sample of over three hundred households in the Murehwa Communal and the Takawira Resettlement Areas was interviewed to gather income and expenditure data. Additionally, income, expenditure and labour allocation of 39 households were closely monitored for one year. Results indicated that the majority of rural households benefited from consumption and sale of indigenous (IF), although the extent varied among households. Within the households, children were the main consumers of fruits. Marketing of IF are carried out by women who used the receipts to purchase household goods. While U. kirkiana fruits were more important in generating cash income than others, fruits of P. curatellifoliawere important for home consumption during periods of food shortages. The gross margins for collection of IFT products were lower than for livestock and crop production. However, returns to labour from collection and use of IFT products were considerably greater than from other activities including gardening and livestock rearing. The study indicates that collection of IFT products is an efficient labour allocation strategy in Zimbabwe. This revised version was published online in June 2006 with corrections to the Cover Date.     

Evaluation of the flammability of gorse (<Emphasis Type="Italic">Ulex europaeus</Emphasis> L.) managed by prescribed burning

• Introduction  

The abandonment of rural areas has led to an increase of the fire-prone European gorse (Ulex europaeus L.) communities in some regions, where prescribed burning is a technique applied to control them. Understanding flammability changes after treatments is crucial for the sustainable use of fire.     

Technical efficiency in timber production and effects of other income sources

In Norway, as in many other European countries, income from forestry has become marginal to owners’ household economies and most employment of forest-owner households is now undertaken off the property. Also, many forest owners have focused increasingly on other revenue-earning activities on their properties, such as providing recreational services. It is a challenge in all kinds of production to find the optimal way of converting inputs into outputs, i.e., to be technically efficient. Extent of financial dependency on income from forestry differs between part-time and full-time forest owners. Since the two groups have different livelihood strategies, it is plausible that full-time forest owners have more professional forest management practices. Data for a cross-section of 3,249 active (i.e., harvesting) forest owners were extracted from the 2004 Sample Survey of Agriculture and Forestry representing the year 2003. A stochastic production frontier analysis was applied to evaluate forest management efficiency impacts of important factors including property and owner characteristics, outfield-related and agricultural activities, off-property income and geographical location in central or remote areas. It was found that many forest owners are technically inefficient, and there exist opportunities for improved performance. Off-property income was found to have an estimated negative impact on technical efficiency, the inefficiency arising (weakly) with increasing share of household incomes from outfield activities, and properties in urban centred areas are less efficient than those in remote areas. One policy implication of the study is that a potentially substantial efficiency increase might be achieved from allowing small inefficient woodlots to merge into larger units of forestry production. Also, providing support for forest management plans may improve efficiency.     

Feedbacks between fuel reduction and landscape homogenisation determine fire regimes in three Mediterranean areas

In densely populated areas like the Mediterranean, wildfire extent is mostly limited by fire suppression and fuel fragmentation. Fire is known to spread more easily through high fuel loads and homogenous terrain and it is supposed to reduce fuel amount and continuity, creating a negative feedback. Here we combine information from administration fire records, satellite imagery fire scars and land use/cover maps to asses the effects of fire on landscape structure and vice versa for three areas in Catalonia (NE Spain). We worked with three spatial focuses: the actual fire scar, 1 km² squares and 10 km² squares. In these regions agriculture land abandonment has lead to increased fuel continuity, paralleled by an increment of fire size. We confirm that fire spread is facilitated by land use/cover types with high fuel load and by homogeneous terrain and that fire reduces fuel load by transforming forests into shrublands. But we also found that fire increased landscape homogeneity, creating a positive feedback on fire propagation. We argue that this is possible in landscapes with finer grain than fire alone would create. The lack of discontinuities in the fuel bed diminishes the extinction capacity of fire brigades and increases the risk of large fires. We recommend that fire management should focus more on conservation of the traditional rural mosaic in order to prevent further increases in fuel continuity and fire risk.     

Assessing fire risk using Monte Carlo simulations of fire spread

Understanding the spatial pattern of fire is essential for Mediterranean vegetation management. Fire-risk maps are typically constructed at coarse resolutions using vegetation maps with limited capacity for prescribing prevention activities. This paper describes and evaluates a novel approach for fire risk assessment that may produce a decision support system for actual fire management at fine scales. FARSITE, a two-dimensional fire growth and behavior model was activated, using ArcView VBA code, to generate Monte Carlo simulations of fire spread. The study area was 300 km² of Mt. Carmel, Israel. FARSITE fuel models were adjusted for Mediterranean conditions. The simulation session consisted of 500 runs. For each simulation run, a calendar date, fire length, ignition location, climatic data and other parameters were selected randomly from known distributions of these parameters. Distance from road served as a proxy for the probability of ignition. The resulting 500 maps of fire distribution (the entire area burnt in a specific fire) were overlaid to produce a map of ‘hotspots’ and ‘cold spots’ of fire frequency. The results revealed a clear pattern of fires, with high frequency areas concentrated in the northwestern part. The spatial pattern of the fire frequency map bears partial resemblance to the fuel map, but seems to be affected by several other factors as well, including the location of urban areas, microclimate, topography and the distribution of ignition locations (which is affected by road pattern). These results demonstrate the complexities of fire behavior, showing a very clear pattern of risk level even at fine scales, where neighboring areas have different risk levels due to combinations of vegetation cover, topography, microclimate and other factors.     

The impact of landscape disturbance on grizzly bear habitat use in the Foothills Model Forest,Alberta, Canada

The Rocky Mountains in Alberta, Canada are subject to a growing number of human activities that cause landscape disturbances. This region is important for large carnivore species such as grizzly bears, whose population decline is a serious management concern. Understanding the impact of landscape disturbance on grizzly bear habitat use is necessary to effectively manage this region and beyond. The goal of this research is to explore the spatial–temporal pattern of habitat use and to characterize the impact of disturbance on use through time. Research was conducted using radio-telemetry location data of female grizzly bears from 1999 to 2003. Kernel home ranges were created annually for three foraging seasons: hypophagia, early hyperphagia, and late hyperphagia. For each season, locations (30 m × 30 m grid cells) were characterized by the temporal persistence or variability in annual use by grizzly bears. Spatial–temporal trends were then compared for disturbed and undisturbed landscapes. Results indicate that in some foraging seasons, particularly hypophagia, the grizzly bear population's use of disturbed areas was proportionally higher than use in undisturbed areas. In other foraging seasons the trends are less clear, but all show instances of preferential selection of disturbed areas. Given that grizzly bear mortality tends to rise when bears use disturbed areas, this preferential selection of disturbed areas is a management concern. To enhance conservation efforts it may be beneficial to control human use in high-quality habitats. This protection may be most important for high-quality habitats used in the spring, as bears appeared to use smaller areas during this period.     

Modeling fire susceptibility in west central Alberta, Canada

Strategic modification of forest vegetation has become increasingly popular as one of the few preemptive activities that land managers can undertake to reduce the likelihood that an area will be burned by a wildfire. Directed use of prescribed fire or harvest planning can lead to changes in the type and arrangement of forest vegetation across the landscape that, in turn, may reduce fire susceptibility across large areas. While among the few variables that fire managers can influence, fuel conditions are only one of many factors that determine fire susceptibility. Variations in weather and topography, in combination with fuels, determine which areas are more likely to burn under a given fire regime. An understanding of these combined factors is necessary to identify high fire susceptibility areas for prioritizing and evaluating strategic fuel management activities, as well as informing other fire management activities, such as community protection planning and strategic level allocation of fire suppression resources across a management area. We used repeated fire growth simulations, automated in the Burn-P3 landscape-fire simulation model, to assess spatial variations in fire susceptibility across a 2.4 million ha study area in the province of Alberta, Canada. The results were used to develop a Fire Susceptibility Index (FSI). Multivariate statistical analyses were used to identify the key factors that determine variation in FSI across the study area and to describe the spatial scale at which these variables influence fire susceptibility at a given location. A fuel management scenario was used to assess the impact of prescribed fire treatments on FSI. Results indicated that modeled fire susceptibility was strongly influenced by fuel composition, fuel arrangement, and topography. The likelihood of high or extreme FSI values at a given location was strongly associated with the percent of conifer forest within a 2-km radius, and with elevation and ignition patterns within a 5-km radius. Results indicated that prescribed fire treatments can be effective at reducing forest fire susceptibility in community protection zones and that simulation modeling is an effective means of evaluating spatial variation in landscape fire susceptibility.     

Altitudinal range shift detected through seedling survival of Ceiba aesculifolia in an area under the influence of an urban heat island

Changes in the position along the elevational gradient for plant species are a predicted consequence of global and local climate change. Within the area of influence of cities it is necessary, for conservation and ecological restoration, to understand the effect on plant communities of climate change and urban heat islands, that can increase the temperature around cities as much as 8 °C when compared with peri-urban rural areas. We explored patterns of seedling survival of Ceiba aesculifolia, a tropical tree species, along an altitudinal gradient in a slope facing the city of Morelia, in Michoacán, México, because the city has followed a trend of increasing mean annual temperatures with a difference of at least 4 °C when compared with the surrounding rural areas. The highest survival was found between 2200 and 2230 m a.s.l. (100% after 1 year of planting and 75% after 2 years), 160 m higher than the altitudinal limit of the remnant adult trees in the study area, and close to the highest limit reported for the species at a regional scale (2200 m a.s.l.). There was a significant effect of altitude on survival among experimental plots (P < 0.0001) and the interaction between elevation and distance from the north side of the experimental area was significant (P = 0.017). For restoring populations of C. aesculifolia within our study region, assisted migration through the establishment of populations at the elevational limit or higher than its historical range might be necessary in areas close to cities that already are under the effects of increased temperatures, but might be necessary also in rural areas for ameliorating the expected effects of global climate change in tropical rural areas.