Restoration of degraded ecosystems in the Afromontane highlands of Ethiopia: comparison of plantations and natural regeneration§

The scale of deforestation in sub-Saharan Africa underscores the need for forest restoration. Information is scarce for evidence-based restoration options. Sown Senna didymobotrya, planted Ficus thonningii cuttings, sown S. didymobotrya and planted F. thonningii combined, and previously occurring native non-browse shrubs (NNS) were compared for their effect on selected plant nutrients and occurrence of Olea europaea subsp. cuspidata in north-west Ethiopia. The treatments were applied to experimental units established on previous grazing land. At the end of the fourth year, 60% of planted F. thonningii stakes survived. The leaf biomass production was encouraging. Senna didymobotrya attained close to 1 m height and crown width. Natural regeneration of O. europaea was observed only under previously occurring shrubs. Six previously occurring NNS species were identified. Soils immediately under these shrubs were richer in nutrients than between shrubs in the open spaces. Our results suggest that vegetative stakes and NNS could be promising tools for ecological restoration of decimated ecosystems in the highlands of Ethiopia. Management interventions, which aim at steering succession close to pre-disturbance forest community structure by facilitation, should be selective of the shrub species.     

Farmers’ perceptions of tree mortality, pests and pest management practices in agroforestry in Malawi, Mozambique and Zambia

Pest management research within the context of agroforestry is in its infancy, and it is often difficult to say when a particular pest justifies investment in research to establish facts. Understanding the potentials and drawbacks of farmers’ indigenous ecological knowledge (ethnoecology) may form the basis for constructive collaboration between farmers, agroforestry scientists and extension staff. Therefore, the objectives of the study were to (1) assess farmers’ knowledge and perceptions of pests, (2) prioritize pest problems that limit tree planting and maize production based on farmers’ own criteria and (3) to identify farmers’ indigenous pest management practices for priority pests. Data were collected using community meetings, individual interviews and direct observation by the first author. The farmers involved in this study in eastern Zambia had over ten years of experience, while most of the farmers in Mozambique and parts of southern Malawi were new to agroforestry. Farmers perceived insects as the major causes of tree mortality, followed by drought, bush fires and browsing by livestock. Among the biological constraints to maize production, insects (particularly termites and stalk bores) and weeds (particularly Striga asiatica) were more important in farmers’ minds than crop diseases. Fundamentally, the farmers’ perception of the causes of tree mortality and crop pests agreed with researchers’ perceptions and the literature. Both termite and witch weed problems were associated with low soil quality, and farmers use various indigenous control practices to control these pests. Some farmers did not know the causes of tree mortality, and hence do not take action. Farmer’s perception of tree mortality was found to be a function of operator-specific variables such as sex, level of education and years of experience with tree species.     

Vegetation structure and regeneration status of the moist,evergreen, afromontane Bore–Anferara–Wadera forest in southern Ethiopia

In a survey of the Bore–Anferara–Wadera forest to study the vegetation structure and regeneration status of woody plant species, 112 quadrats were systematically sampled along altitudinal transects to collect vegetation data. Nested sample plots of 30 m × 30 m and 5 m × 5 m were laid for collecting data on abundance and some variables of tree and shrub size. The regeneration status of woody species was assessed by counting all seedlings within the main sample plot. Woody plant species taller than or equal to 3 m were counted and their height and DBH measured. Density, frequency, basal area and importance value(IV) of woody plant species were computed. A total of 136 vascular plant species belonging to119 genera and 63 families were recorded. The overall Shannon—Wiener diversity value was 3.84 and evenness was 0.78. Total density of trees and shrubs with DBH >2 cm was 1047 ha-1. Size class distribution of woody species across different DBH and height classes indicated a relatively high proportion of individuals at lower classes,suggesting impacts of past anthropogenic disturbances.Analysis of population structure and regeneration status of the forest revealed various patterns of population dynamics where some species were represented by only a few mature plants, suggesting that they are on the verge of local extinction and that immediate conservation measures should be taken. The results highlight the need for joint management and conservation measures by the government, local people and other stakeholders to abate the rapid rate of deforestation and promote sustainable utilization of the forest resources in this forest in southern Ethiopia.     

Farmers’ Motivations to Plant and Manage On-Farm Trees in Ghana

Deforestation and forest degradation, especially in the agricultural landscapes, are serious threats to biodiversity conservation and sustainability of the timber industry. Planting trees on farms has been identified as having great potential to increase forest resources from agricultural landscapes. This paper examined farmers’ motivations and behaviour to engage in on-farm tree planting and management in Ghana by combining internal and external factors in a socio-psychological model. Data were collected from 156 smallholder farmers from five communities in two forest districts using a semi-structured questionnaire. Additional farm inventory data were collected from 33 farmers under two on-farm tree planting schemes. On-farm tree planting was perceived as providing income, access to personal timber for furniture, and access to loan facilities. Incentives such as provision of grants, farming inputs, capacity training, and access to markets for agricultural produce are factors that motivate on-farm tree planting in Ghana. The average standing volume of on-farm trees in the study area is 51.9 m³/ha which is almost twice the national average for the off-reserve areas in the semi-deciduous forests to which much of the study sites belong. Many farmers considered high financial costs and limited knowledge of appropriate techniques in managing planted on-farm trees as barriers to the development of tree stock on farms.     

Farmers’ perspectives on factors limiting tomato production and yields in Kabete,Kiambu County,Kenya

A survey was carried out in Kabete, Central Kenya to establish the limitations and constraints experienced by farmers growing tomatoes. A structured questionnaire was prepared and tested in the field before the actual survey was carried out. Fifty farmers were interviewed and the data analysed established that most farmers lacked enough land, irrigation water, credit and technological knowledge to enable them to optimize tomato production, especially during dry spells when they could fetch premium prices. The average farm size ranged from 0.13 to 1.5 ha and ownership was on a freehold basis. Most households (43%) consisted of five people. A major constraint facing farmers was soil moisture, cited by 50% of farmers interviewed. Nematode infestation and low fertility came second at 25% each. About 60% of the farmers used diammonium phosphates (DAP) for planting and 20% top dressed with calcium ammonium nitrate (CAN). In conclusion, there is a need to provide farmers with reliable irrigation water at affordable prices and credit facilities to enable them to afford inputs such as quality seeds and fertilizers. This will allow them to produce in the dry seasons to take advantage of premium market prices.     

Comparative regeneration status in a natural forest and enrichment plantations of Chittagong （south） forest division, Bangladesh

于2002年4月至11月,对孟加拉Chittagong (南部)林区天然纯林和肥沃地人工林树种更新情况进行了比较研究。共设100个3m×3m的样地(天然林50个,人工林50个)。共记录天然林更新树种64个,苗木密度为24767株/hm2;人工林更新树种40个,苗木密度为18633株/hm2。天然林更新量最大的树种为Castanopsis spp.(2200 株/hm2),其次是Glochidion lanceolarium (2183 株/hm2);人工林更新量最大的树种为Dipterocarpus gracilis (2117株/hm2),其次是Anogeissus acuminata (2000株/hm2)。对天然林而言, Castanopsis spp 的相对密度最高(8.88%), Glochidion lanceolarium 的相对频度最高(7.36%),Syzygium spp. 的相对富有度最高(3.79%),Glochidion lanceolarium的重要值指数最高(18.24%);对人工林而言,Dipterocarpus gracilis的相对密度最高(11.36%),Glochidion lanceolarium的相对频度最高 (9.71%), Dipterocarpus gracilis的相对富有度最高(5.92%), Glochidion lanceolarium的重要值指数最高 (23.32%)。Dipterocarpus gracilis 常见种在天然林和人工林都有更新苗木,但人工林的苗木要高于天然林。天然更新的苗木非常密集,但由于人为的干扰,这些更新的苗木通常达不到径干生长期。表4参35。     

Effects of thinning on microsites and natural regeneration in a Larix olgensis plantation in mountainous regions of eastern Liaoning Province, China

In order to understand the effects of thinning on microsite conditions and natural regeneration in the larch plantation, thinning experiment was conducted in a 40-year-old Larix olgensis plantation in Qingyuan County in eastern Liaoning Province, China in 2003-2004 Five thinning treatments （0%, 10.2%, 19.8%, 29.7% and 40.3% thinned） were designed on the same site. After thinning, canopy openness and the microsite conditions such as photosynthetic photon flux density （PPFD）, soil moisture content, and soil temperature were measured in one growing season. Meanwhile, the investigation of natural regeneration was conducted at the end of the growing season. The results showed that the canopy openness increased with the increase of thinning intensities. PPFD and soil temperature and soil moisture content in different soil layers were positively relative with canopy openness after thinning. The richness of regenerating tree species did not significantly increase （p=0.30） after one growing season since thinning, but the regeneration density and frequency of tree species increased significantly （p〈0.05）. In addition, the number of regenerating tree species increased, and the increment was correlated with the characteristics of iudividual tree species. The increasing percentage of regenerating seedlings of the shade-intolerant tree species was more than that of shade-tolerant tree species. Among the investigated regeneration species, the biggest response of seedling emergency to the canopy openness was Phellodendron amurense. This paper confirmed the following conclusions： after thinning, the variety of regenerating tree species was correlative with the characteristics of regenerating tree species, and the distribution of unthinned trees and the site conditions in the investigated larch plantation were the additional factors influencing, the regeneration.     

Hidden in the woods? Meaning,determining, and practicing of ‘common welfare’ in the case of the German public forests

This article addresses the German debate on the issue of the common welfare designation of public forests. In the first part, drawing on two case studies, the political discourse on the issue is introduced. Two major competing ‘story lines’ can be made out that are both based on a long tradition of controversially discussed concepts of regulatory forest policy. While they both emphasise that common welfare services in forestry run counter to profit orientation, they fundamentally differ with regard to the consequences for forest policy, e.g., considering the degree of state intervention. Afterwards, an overview on the scientific debate on common welfare in the German context is given, and different concepts of common welfare determination are distinguished. Existing approaches of common welfare determination in German forest policy are related to these concepts and discussed. It is argued that the common welfare designation of the public forest is only insufficiently implemented by the actual governance arrangements. Based on this consideration, eventually, the implementation of a procedural concept of common welfare operationalisation in Germany’s public forests at the local level is proposed. While such a concept will not solve all complex problems related to the determination of common welfare in public forestry, it would notably contribute to a more operational definition of common welfare in public forestry and a more informed public debate on the issue.     

Impacts of traditional agroforestry practices,altitudinal gradients and households’ wealth status on perennial plants species composition,diversity, and structure in south-central Ethiopia

Agroforestry Systems - Conspicuous trees and other perennial plants in smallholders’ farms have been acknowledged for their biodiversity conservation values. Impacts of agroforestry...     

Agroforestry Practices among Male and Female Farmers in South–South, Nigeria

Perceptions of the benefits of agroforestry practices (AFPs) and the level of utilization of these practices by male and female participants were examined in the agroforestry programs of the Akwa Ibom and Cross River State Governments of the South–South region of Nigeria. Responses were derived from 250 randomly selected respondents. Overall, respondents perceived the major benefit of agroforestry practices as enhancement of environmental conservation. Female respondents however perceived increased income as the major benefit of agroforestry practices. A composite perception index revealed that women farmers were more favourably disposed than male respondents to the utilization of agroforestry practices. The farmers were favourably disposed to the utilization of only five of the 16 identified AFPs in the study area, including ‘leaving of isolated woody trees on farmlands’, ‘utilizing woody trees as windbreaks’ and to ‘demarcate farm boundaries’, ‘planting of woody trees in combination with fruit trees’, and ‘planting of woody trees in combination with vegetable crops’. Male and female responses were generally similar although a major difference was observed with regard to ‘planting of trees for fuel wood’. The composite index, however, revealed a general low level of utilization of AFPs, although female farmers were relatively more disposed to the utilization of AFPs. The key policy implication of the study is the necessity to embark on sustained education and environmental awareness campaign, with a focus on presenting AFPs as livelihood sustaining and risk mitigation activities, against its present misperception as simply a government strategy to increase the stock of woody trees in the environment. This policy should endeavour to target landless women farmers who have been found to be more interested in the adoption of AFPs into their farming system.     

Smallholder Farmers’ Knowledge of Regulations Governing the Sale of Timber and Supply Chains in Gunungkidul District,Indonesia

Smallholder timber plantations may offer opportunities for farmers to increase their income. Nonetheless, such opportunities are often lost largely due to unfavorable regulations imposed on harvesting and marketing of timber. Adverse impacts are worsened because the regulations are not effectively communicated to smallholder farmers. We assessed the level of smallholder knowledge of existing regulations and found it very low. In part, this correlated to their socio-demographic characteristics. Poor literacy skills and a low level of education make it difficult for older farmers’ to increase their knowledge. This is compounded by the limited information channels that can reach the farmers. Improving smallholders’ knowledge by providing information concerning markets and regulations in a timely and clear manner could help smallholders exercise coping strategies and priorities when selling their timber that would in turn reduce the negative impacts of regulations. The roles of village authorities could be crucial. They are close to the smallholders and could channel the information. The government could provide training and incentives for them to be more active in communicating the regulations to the smallholders.     

Analysis on the Spatial Distribution and Evolutionary Trends of Farmers’ Forestry Income in China

With regard to the implementation of the Collective Forestry Tenure Reform in China, the proportion of forestry income in farmers’ total family income has gradually increased with rapid increases observed in some provinces. Due to these regional disparities, it is important to analyze the spatial distribution and evolutionary trends of farmers’ forestry income to uncover the underlying factors for the existing distribution and note gradual changes from the perspective of economic geography. When spatial distribution and evolutionary trends of farmers’ forestry income data from 31 provinces from 2000 to 2012 were analyzed, we found that farmers’ forestry income during the 13-yr period grew quickly, but the disparities between the highest and lowest income rates gradually widened as large increases in income within a few provinces constituted the bulk of the overall increase across China. We attribute the observed spatial distribution and evolutionary trends to an imbalanced distribution of forestry resources, varying forest species, complicated forestry ownership, multiple forestry policies, differences of labor, and forestry investment.     

Farmers’ objectives toward their woodlands in the upper Midwest of the United States: implications for woodland volumes and diversity

This paper reports the results of a study that explores the relationship between farm woodland owners’ stated intentions for owning woodland, and the structure and composition of these woodlands in the states of Illinois, Indiana and Iowa in the upper Midwest of the United States. Data from two sample-based inventories conducted by the USDA Forest Service, Forest Inventory and Analysis (FIA) program were combined for this analysis—the FIA forest resources inventory and the National Woodland Owner Survey (NWOS). We looked for relationships between product value and investment in woodlands, as reflected in volumes and tree quality. We also examined whether measures of diversity reflected specific management focus. Our results partially supported our hypotheses. Woodland-focused ownership reasons were found to have larger volumes and individual tree sizes. We found that a passive woodland ownership reason—that woods were “part of the farm”—generally had lower volumes per hectare. Although we were not able to differentiate between different forest product classes and measures of volume, we did find that those landowners who harvested veneer had more volume than those who harvested for firewood. Woodland owners who salvage-harvested their woodlands—a harvesting reason that is more reactive than proactive—exhibited lower volumes per hectare than those who harvested for more proactive, product-focused reasons. Biodiversity was also found to be related to the ownership focus and harvest intent. Generally, there was lower diversity in overstory species when the woodland was viewed merely as “part of the farm,” when the product harvested was fence posts and when timber was harvested for salvage or land clearing. The small sample size limits our analysis, but we can conclude that focusing the woodland owners on management of their woodlands—regardless of what the specific management goals might be—should increase productivity and biodiversity of those woodlands.

Farmers’ Willingness to Pay for the Provision of Ecosystem Services to Enhance Agricultural Production in Sene East District,Ghana

This study investigated farmers’ willingness to pay (WTP) by trading food crop as payment for the provision of ecosystem services (ES) to enhance agricultural production and factors influencing their WTP through integrating timber trees on their farmlands in Sene East district, Ghana. A total of 177 farmers were selected from six communities using stratified and simple random sampling. One-on-one interviews were conducted using structured questionnaires. The contingent valuation method was used to gather the data on farmers’ WTP for the provision of ES. A multiple linear regression was run to test factors influencing farmers’ WTP. The results showed that 59% of farmers were willing to pay for the provision of ES. Gender, age, educational status, farmers’ perception to climate change and access to land significantly (p < .001) and positively influence farmers’ WTP. This study identified difficulties in acquiring land, insecure tree tenure and indiscriminate logging as governance challenges that should be addressed to support farmers’ WTP for the provision of ES to enhance agricultural production.     

Variation in biomass expansion factors for China’s forests in relation to forest type, climate, and stand development

? Context

Biomass expansion factors (BEFs, defined as the ratios of tree component biomass (branch, leaf, aboveground section, root, and whole) to stem biomass) are important parameters for quantifying forest biomass and carbon stock. However, little information is available about possible causes of the variability in BEFs at large scales.

? Aims

We examined whether and how BEFs vary with forest types, climate (mean annual temperature, MAT; mean annual precipitation, MAP), and stand development (stand age and size) at the national scale for China.

? Method

Using our compiled biomass dataset, we calculated values for BEFs and explored their relationships to forest types, climate, and stand development.

? Results

BEFs varied greatly across forest types and functional groups. They were significantly related to climate and stand development (especially tree height). However, the relationships between BEFs and MAT and MAP were generally different in deciduous forests and evergreen forests, and BEF–climate relationships were weaker in deciduous forests than in evergreen forests and pine forests.

? Conclusion

To reduce uncertainties induced by BEFs in estimates of forest biomass and carbon stock, values for BEFs should be applied for a specified forest, and BEF functions with influencing factors (e.g., tree height and climate) should be developed as predictor variables for the specified forest.     

Property Rights Effects on Farmers’ Management Investment in Forestry Projects: The Case of Camellia in Jiangxi,China

China’s central government has carried out a series of collectivization and de-collectivization attempts of forest tenure over time, which have led to multiple forest tenure arrangements within provinces. This paper investigates the motivation of farmers to maintain forestry under various forest tenure regimes. First, the paper provides a qualitative analysis of the different forest tenure regimes using the New Property Rights Theory. Second, an econometric analysis based on data from camellia projects in Jiangxi province is carried out. Camellia projects are long-term projects for the production of non-timber forest products which are important for rural income generation. Qualitative results of the research show that a multitude of different tenure regimes exist across forestry projects. Community-based or collective forest management regimes are the most important tenure regimes in forest management in Jiangxi province. Village communities and farmers are the main actors in forest resource management and investment in camellia projects in Jiangxi province. The results of the econometric analysis show that higher degrees of tenure security and residual claimancy for farm households lead to a higher use of household labor and capital within camellia forestry projects. Uncertainty about the future forestland distribution is an obstacle for household investments in forestry.     

Evaluation of regeneration potential of Pinus koraiensis in mixed pine-hardwood forests in the Xiao Xing’an Mountains, China

Large scale harvest of Korean pine(Pinus koraiensis) seeds as a food product in the mixed Korean pine-hardwood forest of northeastern China poses a serious threat to the sustainability and restoration of this endangered regional ecosystem.Seed collection over past decades greatly reduced the seed bank and subsequent seedling and sapling recruitment,and impacting a wide array of granivorous animals that rely on the pine seeds.We surveyed Korean pine seeds,including solid seeds(SS),insect consumed seeds(ICS) and other(animal) consumed(OCS) kernels,of the seed bank(forest floor and the top 10 cm of mineral soil),the seedlings and saplings from 1 m 2 sample plots in five forest types in Liangshui Nature Reserve(LNR) of the southern Xiao Xing’an Mountains in northeastern China to provide accurate information for assessing the Korean pine regeneration potential.The average number of pine seeds in the seed bank were 11.2 seeds/m 2,9.1 seeds/m 2,4.6 seeds/m 2,1.1 seeds/m 2,and 0.2 seeds/m 2 in Korean pine-basswood forest,mixed Korean pine-hardwood forest,mixed conifer-hardwood forest,white birch forests,and oak forests,respectively.In the first three forest types,percentages of SS(potentially viable seeds) were 11.2%,3.5% and 27.8%,respectively.The percentages of ICS(not viable seeds) were consistent at around 35%.The higher but variable percentages of OCS(not viable seeds) indicated high seed predation in these forests.Compared with other studies,we recorded higher percentages of seed damage,probably due to our survey approach and the increased depth of seed bank sampled in our study.Depletion of pine seeds in the seed bank greatly reduced seedling and sapling recruitment.Densities of pine seedlings varied from about 180 trees/ha in the mixed Korean pine-hardwood forest to about 5,400 trees/ha in the mixed conifer-hardwood forests and showed a high degree of spatial variation.Saplings were rare in the mixed Korean pine-hardwood forest,but ranged in the thousands in other forests.Large scale pine seed harvest has seriously threatened the sustainability of the mixed Korean pine-hardwood forest ecosystem.Scaling down the seed harvest or supplemental planting of pine saplings are urgently needed to maintain the health of the existing Korean pine forests and to restore this endangered ecosystem.     

Methane emissions from natural and drained peatlands in the Zoigê, eastern Qinghai-Tibet Plateau

Peatlands are one of the major natural sources of methane(CH_4), but the level of CH_4 efflux is uncertain,especially in alpine peatlands. In this study, CH_4 emission fluxes from natural and drained peatlands on the QinghaiTibet Plateau, southwest China, were measured from June to October in 2013 using the opaque static chamber technique and the Fast Greenhouse Gas Analyzer(DLT-100,Los Gatos Research Corp.). CH_4 emission fluxes ranged from 2.07 to 56.33 mg m~(-2)h~(-1)in natural peatlands and from 0.02 to 0.42 mg m~(-2)h~(-1)in drained peatlands. Mean CH_4 emission flux was 19.13 mg m~(-2)h~(-1)in natural peatlands and 0.14 mg m~(-2)h~(-1)in drained peatlands.These results showed that drainage led to a significant decrease in CH_4 emissions. CH_4 emission fluxes for all sampling plots were significantly correlated with variation in water table depth for linear(R~2= 0.453, P \ 0.01) and exponential functions(R~2= 0.429, P \ 0.01).