Socio-economic factors influencing marketing of non-timber forest products in tropical lowland rainforests of south-western Nigeria§

A number of factors persist to constrain the non-timber forest products (NTFPs) market and, by extension, its potential to contribute meaningfully to livelihood development and poverty reduction objectives. To better utilise the potential of NTFPs, it is important to have a better understanding of the key factors governing the success and failure of NTFPs trade. This paper reports on the market constraints and socio-economic factors that influence trade in five top-priority NTFPs within the tropical lowland rainforests of south-west Nigeria. The NTFPs investigated were bush mango (Irvingia gabonensis), African walnut (Plukenetia conophora), chew-stick (Massularia acuminata), fever bark (Annickia chlorantha) and bush pepper (Piper guineense). Field data were collected in 10 villages located within and around Omo and Shasha forest reserves using a household questionnaire survey. The results showed that seasonality, poor transport, lack of storage facilities and market information were the four main constraints influencing marketing and trade in the NTFPs. In addition, the level of education, gender (sex), household income, ethnicity, distance to the market and access to roads significantly influenced market knowledge and information among households involved in the trade of NTFPs. There is need to improve on the limited source of NTFPs information, enhance skills for product transformation, build innovative storage facilities, and develop the process of domestication and integration in traditional land-use systems.     

Hybrid zone and its genetic analysis： implication for conservation

Hybrid zone is a very critical concept within the evolutionary biology, because it would offer us a better insight to understand the evolutionary role of gene flow and hybridization based on the cline model. This minireview presents an expatia-tion of history perspectives and research developments upon basic concepts including hybrid zones, hybridization, hybrid and its the genetic cline model. Moreover, by figuring out the existing problem around the hybrids within conservative theory and prac-tices, it suggests that the theory of hybrid zone be introduced into conservation biology and it would be provide a broader and more open theoretical background for conservative research and practices.     

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.     

Survival and long-term growth of eucalypts on semi-arid sites in a Mediterranean climate,South Africa§

Four experiments were established on the semi-arid west coast plain of South Africa during the 1990s. The trails tested the survival and growth of several eucalypt species and hybrids, some of which were established in a climate that is drier than their natural distribution range. The aridity indices (AI; defined as mean annual precipitation [MAP]/mean annual potential evapotranspiration) ranged from 0.21 to 0.36 and MAP from 228 to 423 mm. The driest trial site (AI = 0.21 and MAP = 228) had high levels of mortality. However, a number of species (in particular, Eucalyptus gomphocephala, E. camaldulensis and E. tereticornis, as well as individual hybrids of the latter two species with E. grandis) survived and grew well at the remaining sites. Eucalyptus cladocalyx survived well and attained competitive growth rates only on the wettest site in the group (AI = 0.36). The dominant height of the top-performing genotypes at age 5 ranged between 9 and 10 m on the two wetter sites. This corresponded to mean annual increment values in excess of 10 m³ ha^?1 a^?1, which is comparable to volume obtained at more favourable aridity indices in the summer rainfall zone of South Africa and exceeds the growth rates obtained in several other arid zone studies globally. The E. grandis × E. camaldulensis hybrid ranked among the top performers in two trials, but its susceptibility to recently introduced pests and relatively poor wood quality makes it a less attractive choice for planting. The high density and durability of timber, acceptable growth rate (given the low rainfall conditions), and low pest and disease incidence make E. gomphocephala and E. cladocalyx the species of choice for planting in the drier and relatively wetter sections of the semi-arid zone, respectively.     

Regional impact assessment on forest structure and functions under climate change—the Brandenburg case study

A forest simulation model has been applied in a regional impact assessment to investigate impacts of climate change on forest structure and function in the Federal state of Brandenburg, Germany. The forest model FORSKA-M was linked to a GIS that included soil, groundwater table and land-use maps. Two climate scenarios (current climate and a climate change of 1.5 K temperature increase which is combined with a precipitation decrease of 10–20% on average) for 40 meteorological stations in and around Brandenburg were used to assess the sensitivity of species composition to climate change. Furthermore, the implications of vegetation changes for other forest functions were analysed by means of several indicators. To evaluate the impacts of climate change on biodiversity, measures of species diversity (Shannon’s and Simpson’s index) and habitat and structural diversity (Seibert’s index) were applied. The evaluation of impacts on groundwater recharge of natural and managed forests was carried out using the soil water balance model of FORSKA-M.At first, model simulations of the potential natural vegetation (PNV) on the whole area of Brandenburg with different climate scenarios were analysed. The results indicated that climatic warming would lead to a shift in the natural species composition in Brandenburg towards more drought tolerant species. The simulated diversity of the forests would be reduced, and groundwater recharge would be decreased.The majority of forests in the state of Brandenburg have been managed intensively in the past. At present, large areas of Brandenburg’s forests are dominated by pure stands of Scots pine, but current forest management practice aims at increasing the share of deciduous and mixed forests. In order to analyse the possible consequences of climate change on forest management, forest inventory data were used to initialise FORSKA-M with representative forest stands. Simulation experiments with three different management scenarios showed that the short to mid-term effects of climatic change in terms of species composition were not as severe as expected. However, the comparison of different diversity measures indicates a decrease in the species diversity in contrast to an increase in habitat diversity under climate warming. Furthermore, a decrease in productivity and groundwater recharge was simulated under the climate change scenario.The regional impact assessment corroborated the high sensitivity of natural forests in the region to the projected climatic change and it underlined the importance of adaptive management strategies to help forestry to cope with climatic change.     

Insights from behavioural economics for forest economics and environmental policy: Potential nudges to encourage woodland creation for climate change mitigation and adaptation?

Evidence from behavioural economics illustrates how cognitive factors can affect the preferences, values and choices of individual decision-makers. The evidence also shows how policy ‘nudges’ that account for the influence of cognitive factors can shift choices in socially desirable directions. Despite a wide range of potential applications, little research has been published to date applying behavioural economics in forestry. As an example of how behavioural economics could be used, this paper considers the potential for nudges in encouraging woodland creation to help meet climate change mitigation and adaptation goals. Although forests offer significant climate change mitigation and adaptation potential, land managers are often reluctant to create new woodlands, hindering accomplishment of national targets. Nudges could potentially help overcome the barriers. Disaggregating behavioural elements of woodland creation using the Stages of Change model, we identify a number of relevant intervention points at which nudges could be applied. It is argued that nudges may best be tailored towards different types of land manager taking account of differences in attitudes, motivations, circumstances and behaviour. To be effective, a combination with other policy instruments is likely to be needed. Pilot studies are recommended in determining which nudges are cost-effective. The paucity of existing studies drawing upon behavioural economics, or testing out nudges, points to this as a current frontier of both forest economics and policy, but can also be considered a frontier of environmental policy more widely. Developing a consistent valuation framework allowing for the social endogeneity of preferences and for optimization (or some other protocol) to be used in selecting policy options remains a fundamental challenge.     

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....     

Human–wildlife competition for Korean pine seeds: vertebrate responses and implications for mixed forests on Changbai Mountain,China

Introduction  

Korean pine (Pinus koraiensis) is a dominant tree species in the cold temperate mixed forest zone in eastern Eurasia. Its seeds are food sources for wildlife but have become an important and marketable part of the economy for local communities.     

Evaluating the deployment of alternative species in planted conifer forests as a means of adaptation to climate change—case studies in New Zealand and Scotland

Context

A strategy widely proposed for increasing the resilience of forests against the impacts of projected climate change is to increase the number of species planted to spread and reduce the risks from a range of biotic and abiotic hazards.

Aims

We tested this strategy in two case study areas in planted conifer forests in New Zealand and Scotland.

Methods

The performance of the major tree species and an alternative was compared: radiata pine and Eucalyptus fastigata in New Zealand and Sitka spruce and Scots pine in Scotland. The process-based model 3-PG2S was used to simulate the effects of projected climate change at the end of this century, with and without CO₂ fertilisation, upon productivity and financial returns. The effects of an abiotic hazard and two biotic hazards were considered.

Results

Under the current climate, the major species outperform alternatives in nearly all circumstances. However, with climate change, their relative performance alters. In New Zealand, planting of E. fastigata becomes more attractive particularly when various hazards and elevated CO₂ concentrations are considered. In Scotland, Scots pine becomes more attractive than Sitka spruce at lower interest rates.

Conclusions

The major plantation species in both countries are well suited to the current climate, but deployment of alternative species and/or breeds can help to adapt these planted forests to the impacts of climate change.     

Causal effects of shelter forests and water factors on desertification control during 2000–2010 at the Horqin Sandy Land region,China

The Horqin Sandy Land(HSL), the largest sandy land in the semi-arid agro-pastoral ecotone of Northeast China, has been subject to desertification during the past century. In response, and to control the desertification,government implemented the Three-North Shelter/Protective Forest Program, world’s largest ecological reforestation/afforestation restoration program. The program began in1978 and will continue for 75 years until 2050. Understanding the dynamics of desertification and its driving forces is a precondition for controlling desertification.However, there is little evidence to directly link causal effects with desertification process(i.e., on the changing area of sandy land) because desertification is a complex process,that can be affected by vegetation(including vegetation cover and extent of shelter forests) and water factors such as precipitation, surface soil moisture, and evapotranspiration.The objectives of this study were to identify how influencing factors, especially shelter forests, affected desertification in HSL over a recent decade. We used Landsat TM imagery analysis and path analysis to identify the effects of spatiotemporal changes in water and vegetation parameters during2000–2010. Desertification was controlled during the study period, as indicated by a decrease in desert area at a rate of163.3 km2year-1and an increase in the area with reduced intensity or extent of desertification. Total vegetation cover in HSL increased by 10.6 % during the study period and this factor exerted the greatest direct and indirect effects on slowing desertification. The contribution of total vegetation cover to controlling desertification increased with the intensity of desertification. On slightly and extremely severe desertified areas, vegetation cover contributed 5 and 42 % of the desertification reduction, respectively. There were significant correlations between total vegetation cover and water conditions(i.e., evapotranspiration and precipitation)and the area of shelter forests(P 0.0001), in which water conditions and the existence of shelter forests contributed49.7 and 12.8 % to total vegetation cover, respectively. The area of shelter forests increased sharply due to program efforts, but only shrub forests had significant direct effects on reducing the area of desertification categorized as slightly desertified. The reason for the lack of direct effect of increased arbor forests(accounting for 95.3 % of the total increase in shelter forests) on reducing desertification might be that the selected arbor species were not suited to water conditions(low precipitation, high evapotranspiration) prevailing at HSL. The establishment of shelter forests aided control of desertification in the HSL region, but the effect was less than expected. Effective control of desertification in the HSL region or other similar sandy areas will require greater improvements in vegetation cover. In particular,shrub species should be selected for plantation with reference to their potential to survive and reproduce in the harsh climatic and weather conditions typical of desertified areas.     

Species composition and influencing factors of understory woody species in Robinia pseudoacacia plantations on the Loess PlateauOA

Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tabl...     

Relationship between multi-scale climate factors and performance of ecological engineering on the Loess Plateau,ChinaOA

The long-term "Grain-to-Green Program"(GGP)on China’s Loess Plateau is a major global ecological engineering project which has significantly boosted vegetation renewal.Some studies have found that the rate of restoration is quite rapid during the implementation of ecological engineering,however,the influence of multi-scale climatic conditions on the performance of ecological engineering is unclear.In this study,multiple sources of remote sensing data were used to estimate the dynamics of vegetat...