Productivity analysis in nature reserve: A case study in Hunan Province

Although there are abundant natural resources in nature reserves, poverty is a common feature of the social economy in the communities surrounding nature reserves. Income from forestry is still the main source for residents living around nature reserves. The structure of inputs and outputs, i.e. productivity, in the forestry sector in nature reserves is quite different from one reserve to another. Productivity can be measured by Data Envelopment Analysis (DEA) methods owing to the characteristics of DEA. The promotion of productivity in nature reserve is an effective way to improve the living condition in areas neighboring nature reserves. Thus, one typical national nature reserve in Hunan is selected in this study with the intent to measure productivity in the area and then to analyze the factors affecting its productivity.     

Root carbon reserve dynamics in aspen seedlings: does simulated drought induce reserve limitation?

In a greenhouse study we quantified the gradual change of gas exchange, water relations and root reserves of aspen (Populus tremuloides Michx.) seedlings growing over a 3-month period of severe water stress. The aim of the study was to quantify the complex interrelationship between growth, water and gas exchange, and root carbon (C) dynamics. Various growth, gas exchange and water relations variables in combination with root reserves were measured periodically on seedlings that had been exposed to a continuous drought treatment over a 12-week period and compared with well-watered seedlings. Although gas exchange and water relations parameters significantly decreased over the drought period in aspen seedlings, root reserves did not mirror this trend. During the course of the experiment roots of aspen seedlings growing under severe water stress showed a two orders of magnitude increase in sugar and starch content, and roots of these seedlings contained more starch relative to sugar than those in non-droughted seedlings. Drought resulted in a switch from growth to root reserves storage which indicates a close interrelationship between growth and physiological variables and the accumulation of root carbohydrate reserves. Although a severe 3-month drought period created physiological symptoms of C limitation, there was no indication of a depletion of root C reserve in aspen seedlings.     

Developing phase of China＇s system of nature reserves in perspectiveDeveloping phase of China＇s system of nature reserves in perspectiveDeveloping phase of China＇s system of nature reserves in perspective

Up until 2009, 2541 nature reserves had been established in China. However, the process of developing this system of nature reserves was not quite smooth. Various kinds of information related to nature reserves, such as annual growth, the type of nature reserves established, motives behind building a nature reserve, legal instructions and the constitution of government sectors, were collected and analyzed in order to highlight the characteristics of the devel- apment of our nature reserve system. As a result, we identify three phases and their characteristics, i.e., the initial phase from 1956 to 1978, the establishment phase from 1979 to 1996 and the management standardization phase from 1997 to 2009, could be clearly identified. It is suggested that since the establishment of this comprehensive structural frame- work in China, the system should be entering a new developing phase. We recommend that more attentions should be paid on how to guarantee effective management and how nature reserves are able to maintain their value and fulfill their abjectives in the future.     

Review on studies of Eupatorium adenophorum——an important invasive species in China

Eupatorium adenophorum Spreng. was introduced in Yunnan Province of China around 1940. Since then it has been spreading rapidly, particularly in the southern and southwestern parts of China and caused serious economic loss. The biological research and integrated control on E. adenophorum were carried out from 1980‘s in Yunnan Province. Together with other 15 invasive external species, the weed has been listed in the White Paper by The State Environmental Protection Administration of China. This paper briefly reviews thestudies on natural distribution, biological character, ecological character, chemical component, hazard, potential application and the control of E. adenophorum. The research direction for this invasive external species in future was also discussed.     

Status and Advances of Researches on GA 20—oxidases

GA 20-oxidase,the most important limiting enzyme,can catalyze a series of oxidization of GA biosynthesis pathway from GA12 to GA9 and from GA53 to GA20 in the higher plants.This paper reviews the studies on the characters of GA 20-oxidase,the gene and the protein of GA 20-oxidase and the regulation of GA 20-oxidase gene expression n recent years.At the same time,the prospects for the transformation of GA 20-oxidase in agriculture ,forestry and horticulture are also discussed.     

Co-management： transformation of community affair model in Chinese nature reserves

This article analyzes the application of co-management in establishing and zoning nature reserves, explains two types of participatory models, explains the main content and steps required to implement a co-management program, and suggests future direction of co-management. In China, great progress has been achieved since 1956 when the first nature reserve was established. However, conflicts between nature reserve officials and community members, and differences between conservation and utilization of natural resources suggest that the traditional community affair model is unfit to some degree. A more workable and economically sustainable model is recommended. Co-management appears to be the preferred management model. International conservation organizations have carried out projects in Chinese nature reserves in recent years, and co-management is thought to be an effective approach to resolve conflicts coming from community and to improve nature reserves management.     

Ecotourism in nature reserves in China: current situation, problems and solutions

Our presentation focuses on some important issues associated with ecotourism in nature reserves in mainland China. Conducting ecotourism in certain areas in nature reserves is important for its protection. However, some problems do exist because of special conditions in our society and in the current projects of nature reserves themselves, such as water and air pollution, unplanned construction of roads and facilities, damage of core zones and buffer zones, and confused ownership of nature reserves. These problems are discussed and solutions are proposed in detail, and we emphasize the participation of local communities in order to help residents fight against poverty.     

Studies on Heavy Metal Pollution in Soil—Plant System：A Review

Heavy metal pollution in soil-plant system is of major environmental concern on a world scale and in China in particular with the rapid development of industry.The heavy metal pollution status in soil-plant system in China,the research progress on the bioavailability of heavy metals (effecting factors,extraction methods,free-ion activity model,adsorption model,multivariate regression model,Q-I relationship,and compound pollution),and soil remediation are reviewed in paper.Future research and monitoring is also discussed.     

Two effective methods for the evaluating mental work load on machine-operators — Fractal dimensional analysis with the CGSA method —

In Japanese forestry the mental work loads (MWLs) of machine-operators have become one of significant problems. The RR intervals of two harvester-operators were measured in selective thinning operations. Fractal and harmonic components were separated from the spectra of the RR intervals with the Coarse-graining spectral analysis (CGSA) method. As all fractal dimensions concentrated around 1.5, these lower levels were considered that the operators suffered large MWLs from the thinning operations. The power of the 0.10 Hz spectral component of harmonic components reduced definitively in thinning operations, it became evident that thinning operations were stressful work for harvester-operators. As a result of this research, those two methods were proven to be more effective in estimating the MWLs of harvester-operators.     

Study on Cytoplasmic polyhedrosis virus on Dendrolimus superans

Cytoplasmicpolyhedrosisvirus(CPV)ofEendrolimussuperans(DsCPV)isone.oftheimportantpatholo-gensofthelarvaeOfDendFOHffiussuPerans.InoFdertoutiIizeDsCPVincontrol,themorphoIogy,toxicity,infeCtionanddestroyingprocedureinthemidgutofinsectofDsCPVwereStudied.ThecontrolofDen-dIOhffiussuPeranswiththisvirusinasmaIIareainforestwascarriedout.ResearchmethodMorphologyobservationScanningeIectronmicroscopeandtransmissioneIeCtronmicroscopewereusedtoobservethemor-phoIogy.ToxicityteStingThesameamo…     

Effects of thinning on wind damage in Pinus thunbergii plantation ——Based on theoretlcal derlvation of risk—ratios for assessing wind damage

Based on paper of “Theoretical derivation of risk-ratios for assessing wind damage in coastal forest“,wind damage in the pine coasteal forest,which was thinned at four levels in December of 1997,was investigated for four successive growing seasons.Besides wind damage,the wind profiles outside and inside the coastal forest stand and the distributions of optical stratification porosity (OSP) were also observed.Based on these data,risk-ratios of wind damage for both individual trees and stands were estimated according to the methods developed in “Theoretical derivation of risk-ratios for assessing wind damage in a coastal forest“.The results showed that risk-ratios of wind damage,which were calculated from the meen height and diameter only and from the combination of wind and stand sructure profiles,accurately predicted wind damage in the plantation.Relationships between different thinning ratios and incidence of wind damage showed that stand stability decreased soon after the thinning.This was due to the immediate effects of thinning on increasing the canopy roughness and wind load,and on decreasing the sheltering effects from surrounding trees.However,thinning strategies could improve the stability by long-term effects on growthand development of trees against extreme wind.Only canopy damage was recorded during the experimental period,no stem damage was found,even though the maximum 10-min wind speed outside the coastal forest attained 30.2m s^-1.The results obtained in this study indicate that thinning is the most effective silvicultural strategy available for managing coastal forest despite the increased probability of wind damage soon after thinning.     

Influence of growth stresses and material properties on distortion of sawn timber — numerical investigation

? The board distortion that occurs during the sawing and the drying process causes major problems in the utilisation of sawn timber. The distortion is highly influenced by parameters such as spiral grain angle, modulus of elasticity, shrinkage, growth stresses and sawing pattern.

? In this study a finite element simulation of log sawing and timber drying was performed to study how these parameters interact to affect board distortion. A total of 81 logs with different material combinations were simulated. From each simulated log four boards with different annual ring orientation were studied.

? The results showed that the elastic modulus, shrinkage coefficient and growth stresses had a large influence on the final bow and spring deformation. After sawing of the log into boards, the release of growth stresses was the main contributor to the bow and spring deformation. For boards with low modulus of elasticity, the bending distortion became larger than for the boards with high modulus of elasticity. The twist deformation was very small after sawing but increased significantly during drying of the boards. The results showed that spiral grain angle and the board location within the log were the main contributors to the twist deformation.

     

Regeneration of Picea abies forests on highly productive peatlands—clearcutting or selective cutting?

The study was focused on severe forest regeneration problems that are typical for highly productive peatlands. The aim of the study was to give recommendations for practical forestry on how to renew the forests. Experiments with different forest regeneration methods on highly productive peatlands were set up in nine mature Norway spruce (Picea abies (L.) Karst.) forests in northern, central and southern Sweden. The treatments in the study were natural regeneration in shelterwoods (at densities of 140 and 200 stems ha^‐1), planting of bare‐root spruce seedlings after site preparation (mounding) in the shelterwoods and on clearcuts, and planting without site preparation on clearcuts.

Judging from the extent of windthrow in the denser shelterwoods and the stocking of natural regeneration under remaining shelter trees 4–5 years after final cut, shelterwood regeneration is a promising method. On clearcuts, planting without site preparation resulted in poor seedling survival, large extent of damage to the seedlings and small height increment. Planting in mounds on the clearcuts was much more successful. The best survival of planted seedlings was observed in the shelterwoods. Both the denser and the sparse shelterwoods seemed to give satisfactory protection to the seedlings.

Final recommendations on the most suitable forest renewal method(s) will be made in about five years after the removal of the shelter trees.     

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.     

SEGMOD—a techno-economic model for evaluating the impact of segregation based on internal wood properties

Key message

Segregating stands and logs based on internal wood properties is likely to lead to improvements in value for forest and mill owners, but some situations were found where no segregation was the best alternative. Where segregation was the best alternative, segregating logs at the landing, or stands based on pre-harvest inventory assessments, led to the greatest value improvements.

Context

The benefits of segregating stands, stems and logs based on wood properties are not clear due to the high variability of wood properties, poor market signals for wood with superior properties and poor understanding of the costs across the value chain.

Aims

The aim of this study was to determine if the benefits of segregating stands and logs outweighed the additional costs.

Methods

A techno-economic model (SEGMOD) was constructed that allowed comparisons of segregation at different approaches in the supply chain. The model was populated with Pinus radiata (D.Don) stand, cost and price data from companies operating in four forestry regions of New Zealand. A total of 255 segregation scenarios were modelled, which included variations in segregation approach, stand type, stand location, terrain type, market focus and market horizon.

Results

Segregating logs based on internal wood properties led to improvements in stumpage and mill door value for most of the scenario sets evaluated. The No Segregation option was found (infrequently) to be best in unpruned stands. Segregating logs based on pre-harvest inventory assessments or at the landing would appear to be the best approach.

Conclusion

The economic benefits of segregating stands and logs for forest and mill owners outweighed the additional costs in most of the scenarios evaluated.