Intensive forest management — does it pay off financially on drained peatlands?

2019 ◽  
Vol 49 (9) ◽  
pp. 1101-1113 ◽  
Author(s):  
Anssi Ahtikoski ◽  
Hannu Hökkä
Keyword(s):  
Stand Structure ◽  
Active Management ◽  
Considerable Proportion ◽  
Intensive Management ◽  
Annual Increment ◽  
Management Options ◽  
Data Set ◽  
Site Type ◽  
Management Regime ◽  
Management Regimes

There are only a few studies focusing on the financial aspects of management regimes on peatland forests and even fewer studies investigating intensive management. Such studies, however, are urgently needed, particularly in Finland, where a considerable proportion of drained peatlands is reaching a phase requiring active management. An empirical data set derived from the 10th National Forest Inventory (NFI10) is applied for stand-level simulations (MOTTI stand simulator) until final cut. The data are a representative sample of the most common drained peatland site types and their current stand structures in Finland. Based on several different initial stand conditions, tree growth was projected according to four management regimes: (1) passive management (only one clearcut executed), (2) management according to prevailing silvicultural recommendations, (3) stand-level optimum without ditch network maintenance (DNM) and fertilization (FERT), and (4) stand-level optimum with DNM and FERT (intensive management). The intensive management regime financially outperformed the other management options distinctively, regardless of the climatic region, peatland site type, and initial stand structure. However, towards more harsh climatic conditions and a more barren site type, the financial difference between management options flattened out, and silvicultural recommendations even resulted in a higher mean annual increment (MAI) compared with intensive management.

scholarly journals Betula pendula Ssp. distribution and growth in the sub-Carpathian curvature

2021 ◽  
Vol 3 (2) ◽  
pp. 16-22
Author(s):  
Mihai Harpa ◽  
◽  
Lucian Dinca
Keyword(s):  
Betula Pendula ◽  
Stand Structure ◽  
Economic Value ◽  
Wood Products ◽  
Fuel Wood ◽  
Annual Increment ◽  
Ecological Adaptability ◽  
Secondary Species ◽  
Site Type ◽  
Successional Species

Birch ssp. in the sub-Carpathians curvature can be found in composition with beech and other resinous species, unevenly distributed from the mountain peaks at around 1200 m down to 500-600, mainly from high hills to depressions at 600m, rarely seen on plain sites, crossing different geomorphological structures and overall accounting for 3857.1 ha. The main objective of the paper was to analyze the site and stand characteristics of Betula pendula ssp. Roth. in the subCarpathians curvature as followed: stand structure, stand types and stand site types, soils and different metrics, from growth to yields and its connectivity.The ecological adaptability to climate and soil and early fast growth, makes silver birch fulfill the overall requirements as a pioneer species, mostly naturally regenerated. Birch distribution is highly influenced by stand structure having low proportion in compositions, mean height of 15 m at age 50, and a diameter of 20m. Regarding the site, characteristics are more commonly found on fertile soils, corrugated or fragmented site type with a slope of 20-50° and it is distributed as secondary species in stands, averaging 750m in attitude, ranging from 500 to 1200m, 90% being in mixtures with other species with a mean annual increment of approximately 7 m³/year/ha regardless of stand site type. As an early successional species, it serves as a first colonizer but secondary species and quite often as an ecological instrument to improve the soil characteristics, biodiversity and prevent landslides in certain sites, lacking economic value other than fuel wood or other non-wood products.

scholarly journals Long-term effects of shade and input levels on coffee yields in the Pacific region of Nicaragua

2020 ◽  
Vol 346 ◽  
pp. 21-33
Author(s):  
Arlene LÓPEZ-SAMPSON ◽  
Norvin SEPÚLVEDA ◽  
Mirna BARRIOS ◽  
Eduardo SOMARRIBA ◽  
Rodolfo MUNGUÍA ◽  
...  
Keyword(s):  
Climate Change ◽  
Agroforestry Systems ◽  
Timber Species ◽  
Intensive Management ◽  
Long Term Effects ◽  
Annual Increment ◽  
Coffee Yield ◽  
Management Regimes ◽  
Simarouba Glauca ◽  
Coffee Cultivation

The suitability and profitability of coffee cultivation in Central America are at risk due to pest and disease outbreaks, price fluctuations and climate change. Proper shading is claimed to be one of the most promising practices to seek sustainability and better adapt coffee cultivation to climate change in marginal areas. This study recorded and compared coffee cherry yields over a ten-year period from shaded coffee (N-fixing-trees and timber trees) agroforestry systems under different management regimes (conventional vs. organic) in a suboptimal site. Significant differences in production were detected between conventional inputs vs. combination of organic inputs and shade types in some years of the evaluation period. Full-sun cultivation under intensive management was the most productive system for coffee yields, followed by shaded systems under timber trees. Interestingly, and regardless of management systems (intensive conventional or intensive organic) the worst combinations in terms of coffee yield were shaded systems under leguminous species (Inga laurina (Sw.) Willd. + Simarouba glauca DC.). Across all experimental plots, the timber species Simarouba glauca and Tabebuia rosea (Bertol.) DC. grew well, reaching a mean annual increment in diameter of 2.5-3.3 cm/year (age 12 years). Average gross revenues were higher in full-sun and timber-shaded agroforestry systems. Overall, intensive management regimes were the most expensive cultivation system to run but also the best in terms of coffee yield performance.

scholarly journals Impact of Management Regime and Regime Change on Gravel Barrier Response to a Major Storm Surge

2021 ◽  
Vol 9 (2) ◽  
pp. 147
Author(s):  
James A. Pollard ◽  
Elizabeth K. Christie ◽  
Susan M. Brooks ◽  
Tom Spencer
Keyword(s):  
Risk Management ◽  
Storm Surge ◽  
Natural State ◽  
Hydrodynamic Conditions ◽  
Natural Processes ◽  
Management Regime ◽  
Coastal Defense ◽  
Management Regimes ◽  
Coastal Risk ◽  
The Impact

Gravel barriers represent physiographic, hydrographic, sedimentary, and ecological boundaries between inshore and open marine offshore environments, where they provide numerous important functions. The morphosedimentary features of gravel barriers (e.g., steep, energy reflective form) have led to their characterization as effective coastal defense features during extreme hydrodynamic conditions. Consequently, gravel barriers have often been intensively managed to enhance coastal defense functions. The Blakeney Point Barrier System (BPBS), U.K., is one such example, which offers the opportunity to investigate the impact of alternative management regimes under extreme hydrodynamic conditions. The BPBS was actively re-profiled along its eastern section from the 1950s to the winter of 2005, whilst undergoing no active intervention along its western section. Combining an analysis of remotely sensed elevation datasets with numerical storm surge modeling, this paper finds that interventionist management introduces systemic differences in barrier morphological characteristics. Overly steepened barrier sections experience greater wave run-up extents during storm surge conditions, leading to more extreme morphological changes and landward barrier retreat. Furthermore, while high, steep barriers can be highly effective at preventing landward flooding, in cases where overwashing does occur, the resultant landward overtopping volume is typically higher than would be the case for a relatively lower crested barrier with a lower angled seaward slope. There is a growing preference within coastal risk management for less interventionist management regimes, incorporating natural processes. However, restoring natural processes does not immediately or inevitably result in a reduction in coastal risk. This paper contributes practical insights regarding the time taken for a previously managed barrier to relax to a more natural state, intermediary morphological states, and associated landward water flows during extreme events, all of which should be considered if gravel barriers are to be usefully integrated into broader risk management strategies.

scholarly journals THE EFFECTS OF SUCCESSIVE THINNINGS ON THE HYPSOMETRIC FUNCTION FOR Pinus oocarpa STANDS

FLORESTA ◽  
2011 ◽  
Vol 41 (2) ◽  
Author(s):  
Sebastião Do Amaral Machado ◽  
Dalmo Arantes de Barros ◽  
José Roberto Soares Scolforo ◽  
Fausto Weimar Acerbi Junior
Keyword(s):  
Standard Error ◽  
Unbiased Estimate ◽  
Sao Paulo ◽  
Average Height ◽  
São Paulo ◽  
Data Set ◽  
Management Regimes ◽  
Pinus Oocarpa ◽  
Unbiased Estimates ◽  
Multiple Determination

This research aimed to test the hypothesis that successive thinnings mischaracterize the hypsometric function, and that after some thinnings the average height of the plots or of the stand () is an unbiased estimate of the remaining tree heights (hi), that is, ĥi =  . The data were obtained from Duraflora S. A. in Agudos, State of São Paulo. This data set came from the measurement of diameters and respective heights of 1,100 trees equitably distributed in 11 different treatments with ages ranging from 5 to 25 years, and number of thinnings varying between 0 (zero) and 6. The Stoffels model, previously fitted to all treatments, was used to observe the behavior of the following factors: coefficient of multiple determination (R²), standard error of estimate in percent (Syx %), distribution of residuals, and the significance of the b0 and b1 coefficients in each one of the equations. After tests it was confirmed the hypothesis that average height is a precise estimate of hi for the oldest treatments with more than 4 thinnings. This means low Syx % and unbiased estimates, that is, good distribution of residuals.Keywords: Hypsometric curves; management regimes; plantations; Pinus oocarpa.ResumoEfeitos de desbastes sucessivos sobre a função hipsométrica em povoamentos de Pinus oocarpa Shiede. Esta pesquisa teve como objetivo testar a hipótese que desbastes sucessivos descaracterizam a função hipsométrica e que após alguns desbastes a altura média da parcela ou do povoamento () é uma boa estimativa das demais alturas (ĥi), isto é, ĥi = . A base de dados utilizada para testar a hipótese formulada proveio de plantios de Pinus oocarpa, pertencentes à empresa Duraflora S.A., situada no município de Agudos, sudoeste do Estado de São Paulo. Esta base consistiu da altura e diâmetro de 1100 árvores distribuídas igualmente em 11 tratamentos, com variação de idades e número de desbastes. Visando atingir aos objetivos, foi primeiramente ajustado o modelo de Stoffels, separadamente para cada um dos 11 tratamentos, com o fim de observar a tendência dos coeficientes de determinação múltiplos (R2), do erro padrão da estimativa em porcentagem (Syx %), a distribuição dos resíduos e a significância dos coeficientes de interseção (b0) e de inclinação (b1) em cada uma das equações. Após proceder as análises conclui-se que a medida que se aumenta o número de desbastes os R² vão se tornando cada vez mais baixos , porém os Syx % foram sempre inferiores a 10%. Palavras-chave: Curva hipsométrica; regimes de manejo; plantações; Pinus oocarpa. 

scholarly journals Effects of agricultural credit on wheat productivity of small farms in Sindh, Pakistan

2018 ◽  
Vol 78 (5) ◽  
pp. 592-610 ◽  
Author(s):  
Abbas Ali Chandio ◽  
Yuansheng Jiang ◽  
Feng Wei ◽  
Xu Guangshun
Keyword(s):  
Wheat Yield ◽  
Considerable Proportion ◽  
Small Scale ◽  
Small Farms ◽  
Short Term ◽  
Agricultural Credit ◽  
Data Set ◽  
Content Type ◽  
The Impact

Purpose The purpose of this paper is to evaluate the impact of short-term loan (STL) vs long-term loan (LTL) on wheat productivity of small farms in Sindh, Pakistan. Design/methodology/approach The econometric estimation is based on cross-sectional data collected in 2016 from 18 villages in three districts, i.e. Shikarpur, Sukkur and Shaheed Benazirabad, Sindh, Pakistan. The sample data set consist of 180 wheat farmers. The collected data were analyzed through different econometric techniques like Cobb–Douglas production function and Instrumental variables (two-stage least squares) approach. Findings This study reconfirmed that agricultural credit has a positive and highly significant effect on wheat productivity, while the short-term loan has a stronger effect on wheat productivity than the long-term loan. The reasons behind the phenomenon may be the significantly higher usage of agricultural inputs like seeds of improved variety and fertilizers which can be transformed into the wheat yield in the same year. However, the LTL users have significantly higher investments in land preparation, irrigation and plant protection, which may lead to higher wheat production in the coming years. Research limitations/implications In the present study, only those wheat farmers were considered who obtained agricultural loans from formal financial institutions like Zarai Taraqiati Bank Limited and Khushhali Bank. However, in the rural areas of Sindh, Pakistan, a considerable proportion of small-scale farmers take credit from informal financial channels. Therefore future researchers should consider the informal credits as well. Originality/value This is the first paper to examine the effects of agricultural credit on wheat productivity of small farms in Sindh, Pakistan. This paper will be an important addition to the emerging literature regarding effects of credit studies.

Optimum Management Regimes for Uneven-Aged Loblolly-Shortleaf Pine Stands Managed Under the Selection System in the West Gulf Region

1989 ◽  
Vol 13 (3) ◽  
pp. 117-122 ◽  
Author(s):  
James E. Hotvedt ◽  
Yvonne F. Abernethy ◽  
Robert M. Farrar
Keyword(s):  
Basal Area ◽  
Primary Objective ◽  
Selection System ◽  
Shortleaf Pine ◽  
Annual Increment ◽  
Gulf Region ◽  
Decision Variables ◽  
Management Regimes ◽  
Pine Stands ◽  
Optimum Management

Abstract Residual basal area, the ratio of sawtimber to total merchantable basal area, and cutting cycle length were used as decision variables to develop and analyze alternative management regimes for uneven-aged loblolly-shortleaf pine stands managed under the selection system in southernArkansas and northern Louisiana. Sawtimber and pulpwood yields associated with the regimes were calculated from models for all-aged loblolly-shortleaf pine stands with site indices of 85-95 ft (base age 50 yr) developed by Murphy and Farrar (1982, 1983). Optimum economic regimes based on presentnet value (PNV) had low sawtimber to merchantable basal area ratios (0.55) and short cutting cycles (4-5 yr) when compared to the ranges specified for these variables. Optimum sawtimber production regimes based on periodic annual increment (PAI) had high residual basal areas (60-65 ft²/ac),high sawtimber to merchantable basal area ratios (0.70-0.80), and short cutting cycles (4-6 yr). Using sawtimber production as the primary objective in choosing management regimes resulted in a large loss of PNV. The loss of annual sawtimber production was relatively low, however, when PNVwas used as the objective. South. J. Appl. For. 13(3):117-122.

Assessing management options for wastewater treatment works in the context of life cycle assessment

1998 ◽  
Vol 38 (11) ◽  
pp. 23-30 ◽  
Author(s):  
F. J. Dennison ◽  
A. Azapagic ◽  
R. Clift ◽  
J. S. Colbourne
Keyword(s):  
Wastewater Treatment ◽  
Global Warming ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Global Warming Potential ◽  
Water Utilities ◽  
Management Options ◽  
Management Regimes ◽  
Treatment And Disposal ◽  
The Uk

This paper presents the preliminary results of a Life Cycle Assessment (LCA) study comparing different wastewater treatment works, operated by Thames Water Utilities Ltd. in the UK. Fifteen works have been studied, representing a range of size and type of treatment works. Five management regimes for centralising sludge treatment and disposal were analyzed in the context of LCA to provide guidance on choosing the best practicable environmental option (BPEO). Consideration of Global warming potential indicates that the four proposed management regimes with centralisation of sludge for treatment and disposal, as adopted by Thames Water Utilities Ltd., is an environmental improvement upon the current practice. One of these options, that of complete centralisation and composting of sludge prior to disposal, exerts the least environmental impact with respect to Global warming potential. This suggests that the adoption of composting at Crawley is environmentally preferable to increasing the digestion facility at this works.

scholarly journals DOES CROWN CLASS CLASSIFICATION IMPROVE THE INITIATION AND DEVELOPMENT ANALYSIS OF POST-FIRE PINUS BRUTIA STANDS?

CERNE ◽  
2017 ◽  
Vol 23 (1) ◽  
pp. 61-68
Author(s):  
Diamantis Bountis ◽  
Elias Milios
Keyword(s):  
Stand Structure ◽  
Basal Area ◽  
Ground Level ◽  
Age Difference ◽  
Cross Sectional ◽  
Pinus Brutia ◽  
Site Type ◽  
Annual Growth Rings ◽  
Development Analysis

ABSTRACT The present study was conducted in Pinus brutia Ten. stands which were created after the forest fire of 1989, in the island of Thassos. In 2008, 45 plots of 5 x 5 m were randomly established in three site types. In each plot, the trees were counted, while the breast height diameter of trees was measured. All trees were classified as dominant, codominant, intermediate or suppressed. In each plot, one tree from each crown class was selected (a total of 160 trees) and were cut down. From each tree a cross-sectional disc was cut from the ground level and the number of annual growth rings was counted. A few years of age difference between trees in post fire establishment determined the crown class of a tree. The age difference and the number of trees were reduced from the less productive site type to the more productive site type. Codominant trees were (or will become) the crown class with the most numerous trees in the main canopy. Dominant trees were one of the most, if not the most, significant elements of stand structure and production regarding basal area. This was not the case in low productivity site type as a result of delayed dimension differentiation. Analysis of young P. brutia stands, through the classification of trees into crown classes, increased the amount of attained information, since it provided an improved insight in the competition regime.

scholarly journals Population parameters of the endangered titi monkey, Callicebus coimbrai Kobayashi and Langguth, 1999, in the fragmented landscape of southern Sergipe, Brazil

2011 ◽  
Vol 71 (3) ◽  
pp. 569-575 ◽  
Author(s):  
RRD. Chagas ◽  
SF. Ferrari
Keyword(s):  
Atlantic Forest ◽  
Considerable Proportion ◽  
Reliable Estimate ◽  
Line Transect ◽  
Fragmented Landscape ◽  
Forest Fragments ◽  
Population Parameters ◽  
Data Set ◽  
In The Wild ◽  
A Site

The recently-discovered titi, Callicebus coimbrai, is endemic to the coastal Brazilian Atlantic Forest south of the São Francisco River, a region with a long tradition of deforestation. While a number of C. coimbrai populations have now been identified, little is known about basic population parameters. Considering the importance of this information for conservation planning, the population of a site in southern Sergipe (with a total area of forest of approximately 500 ha) was surveyed between April and October 2008. Standard line transect procedures were used in the four largest fragments, and additional monitoring included the use of playback broadcasts for the observation of titi groups. The presence of titis was confirmed in all the forest fragments at the site, including one of only five hectares. Two other primates - Callithrix jacchus and Cebus xanthosternos - were also recorded at the site, but were less abundant than titis. A total transect walk of 476 km provided 164 sightings of primates, the majority of which (104) were of Callicebus coimbrai. Titi groups ranged in size between two and five individuals. The most reliable estimate of overall population density, derived from the combined data set, was 12.6 individuals per km²;, although density was much higher in smaller (more disturbed) fragments. The total population of Callicebus coimbrai at the site was estimated to be at least 50 individuals, which may represent a considerable proportion of the population of the species remaining in the wild. In addition to its apparent tolerance of habitat fragmentation, densities of C. coimbrai recorded at the site compare favourably with those of other Atlantic Forest titi species.

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