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1.
A model of public cost-sharing in private forest investment is proposed to describe the substitution between the private financing of investments and public investment assistance. The substitution depends on the curvature conditions of the forest investment function on forest stock. When the second-order investment effects are close to zero or when they do not exist, the funding substitution will not take place. A simultaneous econometric model for private and public funding employing forest incomes, forest income taxes, interest rates, investment scale and market wood price expectations as exogenous variables is estimated. The model estimation based on Finnish regional data in 1983–2000 rejects the substitution alternative. A 10% increase in private investment funding increases the demand for public funding at the same rate, but a 10% increase in public funds will increase the private funds supply by 2.5%. Significant income effects are found only in the case of private funding. In northern Finland, the scale effects are large for public financial assistance. The effects of the income tax reform on the private supply of funds are positive, especially for the new wood-sales profit taxation, whereas the interest rate and price expectation effects are negative.
相似文献
Mikael LindenEmail: Phone: +358-13-2514225Fax: +358-13-2513290 |
2.
Sonia Graham Heather M. McGinness Deborah A. O’Connell A. O. Nicholls 《Small-Scale Forestry》2008,7(2):183-203
Investment in small and large-scale revegetation in Australia is growing in response to concerns regarding the sustainability
and productivity of agricultural landscapes. Site preparation and management––such as soil cultivation, weed control, fertilising,
mulching, use of treeguards and watering––are major costs associated with small-scale revegetation. The aim of this study
has been to investigate local revegetation knowledge and practices to determine the usefulness of each management practice
for achieving success and to determine whether some practices are more suited to particular climatic zones. A national online
revegetation survey was conducted to ascertain current small-scale revegetation practices and the factors that drive these
choices. Management practices were found to be strongly associated with climate. Mulch, fertiliser, weed control and watering
were applied more frequently in higher rainfall and higher temperature zones. Soil cultivation and treeguards were used more
frequently in lower rainfall and lower temperature zones. These findings suggest that there may be some benefit in modifying
existing revegetation guidelines to reflect climatic zones and management flexibility.
相似文献
Sonia GrahamEmail: |
3.
Development of wood procurement in Northwest Russia: round wood balance and unreported flows 总被引:2,自引:0,他引:2
This paper analyses industrial round wood flows into, within, and out of Northwest regions of Russia. We examine sawlogs, pulpwood, and fuelwood used for industrial purposes obtained from logging, and chips obtained from the wood-processing industry. We attempt to clarify different recent trends in wood harvesting, industrial round wood export, and forest industries development that have an influence on unreported wood in Russia. Our method, which uses wood balance diagrams, provides an interpretation of data from different Russian sources in order to offer better transparency regarding wood flows from forests to mills. It also helps to explain the apparent imbalance between round wood supply and demand and it helps one to assess the possible share of unreported industrial round wood production in Northwest Russia. Based on annual forest-related statistical data available from the Ministry of Natural Resources, the State Committee of Statistics, and the Russian Federation’s Customs Department, unreported round wood flows can be estimated to be 23% of the total industrial round wood production, or approximately 9 million m3 u.b. per year. Unreported round wood flows are more common in export oriented regions that have poorly developed forest industries.
相似文献
Yuri GerasimovEmail: Phone: +358-102-113253Fax: +358-102-113251 |
4.
The farm forest resource in Ireland: opportunities and challenges for rural development in Ireland 总被引:1,自引:0,他引:1
Niall Farrelly 《Small-Scale Forestry》2007,6(1):49-64
A critical mass of farm forestry and private forestry is now developing in Ireland with over 211,000 ha planted since 1980,
with 190,000 ha of this planted since 1990. Currently, 90,000 ha of private forests are over 10 years of age, with 41,000 ha
over 15 years of age. This paper examines the potential of the farm forest resource in Ireland and highlights some issues
that need to be addressed in order that the full potential of farm forestry is realised. It is estimated that 876,000 m3 of timber is currently available from forests through removals from thinning operations from plantations that are at or have
passed first thinning age. Cumulative volume output from thinning could be as high as 1.9 M m3 by 2010 increasing to 5.9 M m3 by 2015. Farm forestry has the potential to be a financially important farm enterprise with 15% of farmers (16,460) currently
engaged in forestry in Ireland. The development of volume production forecasts will provide crucial supply information for
gearing up of the wood-processing sector for additional volume from farms. However many enterprises face high harvesting and
extraction costs. Solutions to overcoming economies of scale due to the small size of plantations (averaging 9.2 ha) are proposed
using methods to group forestry operations together. The network of small sawmills throughout the country is favourable for
private growers as analysis indicates that 82% of private forests are within 32 km of a sawmill and efforts to stimulate local
processing are being encouraged. Financial analysis indicates that farmers can increase forestry returns by thinning their
plantations. The risk of windthrow to plantations is one of the major factors that can lead to financial losses in farm forestry
in Ireland and can be reduced by adequate management planning. A series of forestry extension programs will provide farmers
with adequate information to help aid decision-making in managing their plantations.
相似文献
Niall FarrellyEmail: |
5.
Future harvesting pressure on European forests 总被引:1,自引:0,他引:1
G. J. Nabuurs A. Pussinen J. van Brusselen M. J. Schelhaas 《European Journal of Forest Research》2007,126(3):391-400
We provide quantitative insight in the spatial distribution of the future supply of wood as a raw material from European forests
(27 countries) until 2060. This supply is tested for two scenarios: ‘projection of historical management’ and ‘new management
trends’ and compared against a benchmark scenario. The new management trends scenario incorporates influences of issues as
nature-oriented management, carbon credits and increased demand for bio-energy. The results of these projections provide insight
in the state of the European forests and indicate that under the ‘new management trends’ supply can still increase to 729 million m3 by 2060 in Europe, whereby almost throughout Europe we allow harvest to be higher than increment for some time. Without linking
countries dynamically through international trade, we identify regions where harvesting pressure is highest. Under the new
management trends scenario, the harvested volume is reduced with 82 million m3/year (compared to ‘projection of historical management’) because of stricter management constraints. However, the management
regimes as parameterised here allow harvesting pressure to remain highest in Central Europe and some Scandinavian countries,
notably Finland and Norway.
相似文献
G. J. NabuursEmail: |
6.
Edward Warren R. Geoff B. Smith Luis Alejandro Apiolaza John C. F. Walker 《New Forests》2009,37(3):241-250
The effects of stocking on wood stiffness (MoE) for three Eucalyptus species are quantified using a 6-year-old trial established in New South Wales, Australia. An acoustic time-of-flight tool
measured the velocity between two probes in the outerwood, from which the stiffness was estimated. Four stocking levels (714,
1,250, 1,667 and 3,333 sph) were examined. Stiffness varied significantly between all species, with E. cloeziana showing the highest stiffness (14.2–15.7 GPa), followed by E. pilularis (12.2–13.5 GPa) and E. dunnii (10.7–12.6 GPa). There was a stiffness increase (around 11%) between 714 and 1,250 stems/ha for all species but thereafter
differences between stockings were not always significant. Trees were also assessed for basic density, dbh, total height, crown area, green crown height and stem slenderness (height/dbh). Only stem slenderness had a significant association (0.41 ± 0.17) with stiffness. These findings suggest that, where stiffness
is a priority, forest managers could reduce establishment costs with low stockings (around 1,250 stems/ha).
相似文献
Luis Alejandro ApiolazaEmail: |
7.
R. Grammel 《Forstwissenschaftliches Centralblatt》1990,109(1):119-129
Die bisher erarbeiteten Ergebnisse lassen sich wie folgt zusammenfassen:
Results achieved till now may be summarized as follows:
相似文献
1. | Bei der Fichte korrelieren Jahrringbreite und Holzdichte und damit die wesentlichen Festigkeitseigenschaften, wie Biegefestigkeit, Biege-E-Modul, Druckfestigkeit. |
2. | Die Holzdichte als wesentliche Eigenschaft steht in enger Beziehung zum Sp?tholzanteil. |
3. | Die Astst?rke korreliert direkt mit der Wachstumsgeschwindigkeit, d. h. ebenfalls mit der Jahrringbreite. |
4. | Astst?rkensumme und Jahrringbreite zusammen erkl?ren einen gro?en Teil der technischen Holzeigenschaften. |
5. | Durch Wert?stung kann ein Teil der negativen Wirkungen des schnellen Wachstums auf die Festigkeitseigenschaften ausgeglichen werden. |
6. | Dies bedeutet allerdings nicht, da? die Holzdichte als wesentliches Merkmal an Bedeutung verliert. |
7. | Eine weitgehend zu erwartende Reihung ist also aus holztechnologischer Sicht eindeutig festzustellen: |
– | — engringig und wertge?stet auf dem 1. Platz, verspricht also h?chsten Holzwert, |
– | — engringig, nicht wertge?stetes Holz steht an 2. Stelle, |
– | — weitringig, wertge?stet im Mittelfeld, nur knapp nach Position 2 |
– | — weitringiges, nicht wertge?stetes Holz verliert, mit Abstand an letzter Stelle stehend. |
1. | With spruce, annual ring width is correlated with wood density, and thus with the essential strength properties such as bending strength, bending-E-module, and tensile strength. |
2. | Wood density as an essential property is closely related to the share of late wood. |
3. | There is a direct correlation between knot size and growth rate, i. e. also annual ring width. |
4. | The sum of knot diameters and annual ring width together explain a large part of the technical wood properties. |
5. | High pruning may compensate for some of the negative effects of rapid growth on strength properties. |
6. | This, however, does not imply that wood density is becoming less important as an essential property. |
7. | From the wood-technological viewpoint, a largely to be expected ranking can be clearly established: |
– | — narrow growth rings and high-pruned stands in first place, thus promising the highest timber value, |
– | — narrow growth rings but not pruned comes second, |
– | — wide growth rings and high-pruned ranks about in the middle, only slightly behind position 2, |
– | — wood showing wide growth rings and not being from pruned trees falls way behind. |
8.
A farm-level financial feasibility was performed to examine the use of shelterbelts as a swine odor mitigation technology.
Shelterbelts are purposefully planted rows of trees and shrubs around the main sources of swine odor—swine buildings, manure
storage systems, and crop fields that receive land applied manure. By using a series of model pork finishing farms and a number
of differing shelterbelt design scenarios, the shelterbelt establishment and long-term (20 years) maintenance costs were calculated
using a discounted cash flow analysis. Total costs for examined pork finishing farms, depending upon the shelterbelt design
scenario, and whether or not government cost-share programming was used, ranged from $0.01 to $0.65 per pig produced. Study
results emphasized the importance of cost-share programs, particularly Environmental Quality Incentive Program (EQIP). In
most cases, both with and without cost-share programming, the total costs were well below reported pork producer expenditures
for odor management.
相似文献
John C. TyndallEmail: |
9.
Subhrajit K. Saha P. K. Ramachandran Nair Vimala D. Nair B. Mohan Kumar 《Agroforestry Systems》2009,76(1):53-65
Conservation of biodiversity and mitigation of global warming are two major environmental challenges today. In this context,
the relationship between biodiversity (especially plant diversity) and soil carbon (C) sequestration (as a means of mitigating
global warming) has become a subject of considerable scientific interest. This relationship was tested for homegardens (HG),
a popular and sustainable agroforestry system in the tropics, in Thrissur district, Kerala, India. The major objectives were
to examine how tree density and plant-stand characteristics of homegardens affect soil C sequestration. Soil samples were
collected at four depths (0–20, 20–50, 50–80, 80–100 cm) from HG of varying sizes and age classes, and their total C content
determined. Tree density and plant-stand characteristics such as species richness (Margalef Index) and diversity (Shannon
Index) of the HG were also determined. Results indicated that the soil C stock was directly related to plant diversity of
HG. Homegardens with higher, compared to those with lower, number of plant species, as well as higher species richness and
tree density had higher soil carbon, especially in the top 50 cm of soil. Overall, within 1 m profile, soil C content ranged
from 101.5 to 127.4 Mg ha−1. Smaller-sized HG (<0.4 ha) that had higher tree density and plant-species density had more soil C per unit area (119.3 Mg ha−1) of land than larger-sized ones (>0.4 ha) (108.2 Mg ha−1). Soil C content, especially below 50 cm, was higher in older gardens. The enhanced soil-C storage in species-rich homegardens
could have relevance and applications in broader ecological contexts.
相似文献
Subhrajit K. SahaEmail: |
10.
Riitta Hänninen Anne Toppinen Ritva Toivonen 《European Journal of Forest Research》2007,126(1):111-120
In the European sawnwood markets, competition is tight between producer countries, with the new EU countries gradually gaining
larger market shares. This paper focuses on the pass-through of sawnwood prices to supplier countries’ national roundwood
prices. Price-change effects on market shares are known to be large, but not so much is known about the timing and duration
of price transmission between competitor countries. Our empirical analysis concerns the exports of four large sawnwood supplier
countries in Europe (Finland, Austria, Estonia and the Czech Republic) to German markets, using quarterly panel data for 1995–2003.
The transmission process was found to differ between countries, and the relationship was most clearly detectable between Finnish
sawlog and sawnwood prices. Results based on seemingly unrelated regression analysis indicated that price transmission exhibits
similarities between old (i.e. Austria, Finland) and new EU member countries (Estonia, Czech Republic). Overall developments
in both sawnwood and sawlog prices displayed convergence in the study period, which indicates that deepening integration in
European markets is also detectable in the forest sector.
相似文献
Ritva ToivonenEmail: |
11.
– |
• We present the results of a two-year (2007–2008) greenhouse study investigating the effect of water availability and nitrogen
fertilization on the growth, biomass partitioning, and foliar nutrient content of Abies fraseri (Pursh) Poir. 相似文献
12.
This study aims at developing a satellite-based methodology for the implementation of two Ministerial Conference on the Protection
of Forests in Europe indicators for the European Alpine Bio-geographic region, and their changes over time: (1) area of forest
cover and (2) forest spatial pattern. The northern Carpathians were selected as a study area due to the documented recent
increase of forest cover. Changes of forest cover were quantified using Landsat images for the years 1987 and 2000. Single-date
forest–non-forest maps were derived by image segmentation and supervised classification, including the use of ancillary data
(CORINE Land Cover and a digital elevation model). These maps were an input for the post-classification change detection.
The forest spatial pattern maps with four classes (core, patch, edge and perforated forest) were derived with morphological
image processing. A simple method to mask uncertainty areas on forest maps and related products was also developed. The accuracy
of the resulting forest–non-forest map was assessed with orthophotos and amounts to 93.9%. Uncertainty areas, for which change
assessment was judged more difficult and less reliable, were not considered for assessing forest cover change. The annual
forest cover change rate of 0.38% was found over the 1987–2000 period. For the 13-year time period, we found a decrease of
core forest and an increase of patch and perforated forest. We conclude that the proposed methodology allows to quantify changes
of forest cover and forest spatial pattern at ∼1 ha minimum mapping unit.
13.
R. Bergwelt 《Forstwissenschaftliches Centralblatt》1989,108(1):310-318
Der Wald ist für den Naturschutz
14.
Carbon sequestration in the woody biomass of shelterbelts has been investigated but there have been no measurements of the
C stocks in soil and tree litter under this agroforestry practice. The objective of this study was to quantify C stored in
surface soil layers and tree litter within and adjacent to a 35-year-old shelterbelt in eastern Nebraska, USA. The 2-row shelterbelt
was composed of eastern red cedar (Juniperus virginiana) and scotch pine (Pinus sylvestris). A sampling grid was established across a section of the shelterbelt on Tomek silt loam (fine, smectitic, mesic Pachic Argiudolls).
Four soil cores were collected at each grid point, divided into 0–7.5 and 7.5–15 cm depth increments, and composited by depth.
Soil samples were analyzed for total, organic, and inorganic C, total N, texture, pH, and nutrient content. Under the shelterbelt,
all surface litter in a 0.5 × 0.5 m2 area at each grid point was collected prior to soil sampling, dried, weighed, sorted, and analyzed for total C and N. Average
soil organic carbon (SOC) in the 0–15 cm layer within the shelterbelt (3,994 g m−2) was significantly greater than in the cultivated fields (3,623 g m−2). The tree litter contained an additional ∼1,300 g C m−2. Patterns of litter mass and soil pH and texture suggested increased organic inputs by tree litter and deposition of wind-blown
sediment may be responsible for greater SOC beneath the shelterbelt. Further research is needed to identify the mechanism(s)
responsible for the observed patterns of SOC within and adjacent to the shelterbelt and to quantify the C in biomass and deeper
soil layers.
15.
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