2,982 research outputs found
Estimation of carbon storage of forest biomass for voluntary carbon markets: preliminary results
No full textEstimating the carbon storage of forests is essential to support climate change mitigation and promote the transition into a low-carbon emission economy. To achieve this goal, voluntary carbon markets (VCMs) are essential. VCMs are promoted by a spontaneous demand, not imposed by binding targets, as the regulated ones. In Italy, only in Veneto and Piedmont Regions (Northern Italy), VCMs through forestry activities were carried out. Valle Camonica District (Northern Italy, Lombardy Region) is ready for a local VCM, but carbon storage of its forests was never estimated. The aim of this work was to estimate the total carbon storage (TCS; t C ha−1) of forest biomass of Valle Camonica District, at the stand level, taking into account: (1) aboveground biomass, (2) belowground biomass, (3) deadwood, and (4) litter. We developed a user-friendly model, based on site-specifc primary (measured) data, and we applied it to a dataset of 2019 stands extracted from 45 Forest Management Plans. Preliminary results showed that, in 2016, the TCS achieved 76.02 t C ha−1. The aboveground biomass was the most relevant carbon pool (48.86 t C ha−1; 64.27% of TCS). From 2017 to 2029, through multifunctional forest management, the TCS could increase of 2.48 t C ha−1 (+3.26%). In the same period, assuming to convert coppices stands to high forests, an additional TCS of 0.78 t C ha−1 (equal to 2.85 t CO2 ha−1) in the aboveground biomass could be achieved without increasing forest areas. The additional carbon could be certifed and exchanged on a VCM, contributing to climate change mitigation at a local level
Biomass and biofuels
No full textBiomass includes all materials that contain organic carbon bound in the chemical structure of molecules, resulting from the chlorophylline photosynthesis, carried out by autotrophies organisms. Lots of biomass from agricultural, agri-food and forestry sectors can be used for energy purposes, representing an essential renewable energy source that, if appropriately managed, can help to reduce the negative environmental impacts arising from the exploitation of fossil fuels. The possibility of using biomass for a specific production process mainly depends on its physical and chemical properties. This paper is organized in two sections: in the first one, the most important biomass used worldwide for energy generation (thermal energy and/or electric energy), as well as its properties, are described. In the second one, the main biomass-to-energy processes (thermochemical and biochemical conversions) are shortly explained. Finally, some emerging techniques (such as bio-methane and bio-hydrogen production) are discussed in more detail
ASSESSMENT OF WOOD BIOMASS AND CARBON STOCK AND EVALUATION OF MACHINERY CHAINS PERFORMANCES IN ALPINE FORESTRY CONDITIONS: AN INNOVATIVE MODELLING APPROACH
No full textThe PhD Thesis focuses on two topics: (i) assessment of forest wood and carbon (C) stock and (ii) forestry mechanization applicable at the forest stand level for any given conditions among those found in the Italian Alpine and pre-Alpine mountainous areas. Both these topics aim to improve the use of forestry resources for climate change mitigation, starting from a bottom-up approach scaled on the information made available by Forest Management Plans (FMP).
After an introduction on the topics given in chapter 1, the first topic (assessment of forest wood and C stock) is investigated in chapters 2, 3, 4 and 5, by taking the Valle Camonica District (Lombardy Region, Italy) as Case Study Area. The aim is to develop a stand-level model to estimate the mass of wood (t·yr-1 dry matter, DM) and C (t·yr-1 C) in aboveground wood biomass, belowground wood biomass and dead organic matter (i.e., deadwood and litter), quantifying, at the same time, the mass of potentially available logging residues (i.e., branches and tops; t·yr-1 DM) for energy generation and the corresponding potentially generated energy (GJ·yr-1), under the assumption that wood replaces non-renewable energy sources.
Chapter 2 presents the first version of the model, called “WOody biomass and Carbon ASsessment” (WOCAS v1), aimed at the quantification of the mass of wood and C in the forest pools in a predefined reference year, by using a methodology already applied at the regional and national level. The model was tested on a dataset of 2019 public forest stands extracted from 45 FMPs (area: 37000 ha) covering the period from 1984 (year in which the oldest FMP came into force) to 2016 (most recent available data from the local FMPs). Preliminary results showed that, in 2016, the total C stock (given by the sum of C stock in aboveground wood biomass, belowground wood biomass, and dead organic matter) achieved 76.02 t·ha-1 C. The model also gives the possibility to analyze future scenarios based on the continuation of the current management practices rather than improved practices, to define a possible mitigation strategy for the activation of a local Voluntary Carbon Market.
WOCAS v1 was implemented into a second version (WOCAS v2), by introducing, first of all, an improved methodology to calculate the mass of wood (t·yr-1 DM) and C (t·yr-1 C) within the forest pools from the year in which the FMPs entry into force until a predefined reference year (chapter 3). The main innovative aspect of the improved methodology is that the gross annual increment of each stand is calculated through an age-independent theoretical non-linear growth function based on the merchantable stem mass, solving the limitation of WOCAS v1 in which the gross annual increment of the stand is assumed as constant, as reported by the FMPs. This improved methodology was applied to the same dataset used for WOCAS 1 (i.e., 2019 forest stands, 45 FMPs; forest area: 37000 ha; period: 1984-2016). The total weighted average wood yield, calculated as the sum of wood yield in all the above-mentioned forest pools, ranged from 53.36±53.13 t∙ha-1∙yr-1 DM (1984) to 156.38±79.76 t∙ha-1∙yr-1 DM (2016). The total weighted average C yield ranged from 26.63±26.80 t∙ha-1∙yr-1 C (1984) to 77.45±40.19 t∙ha-1∙yr-1 C (2016). The average C yield related to the whole analyzed period (1984-2016) was 66.04 t∙ha-1 C. Of this, C yield in the aboveground wood biomass, belowground wood biomass and dead organic matter was equal to 72.0%, 15.8% and 12.2%, respectively.
Validation of the results at the stand level was performed by comparing the value of the gross annual increment provided by the FMPs with the one predicted by WOCAS v2. The model caused, in some cases, an overestimation and, in other cases, an underestimation. For example, for Larix decidua Mill. and for Picea abies L., the Pearson coefficient of correlation (r2) between predicted and provided increments was r2 = 0.69 and r2 = 0.46, respectively. This was due to the fact that the methodology currently implemented into WOCAS v2 is based on average values of growth parameters valid for the whole Lombardy Region, and does not consider the productivity class of the stands since specific information was not always made available by the FMPs.
WOCAS v2 also includes an innovative methodology (chapter 4 and chapter 5) to quantify – as an additional climate change mitigation strategy – the mass of potentially available residues (t·yr-1 DM) for energy generation, the potentially generated heat and electricity (GJ·yr-1) and the potentially avoided CO2 emissions into the atmosphere related to the final combustion process (t·yr-1 CO2), under the assumption that wood substituted non-renewable energy sources. In chapter 4, since not all the required data were initially made available for the Case Study Area, the mass of residues was computed by considering only the stand’s function and the stand’s management system, covering the period from 1994 (year in which the first wood cut was performed) to 2016.
The calculation was then improved (chapter 5) by taking into account also the stand’s accessibility, the forest roads’ transitability and the energy market demand. Information on topographic features, landscape morphology and characteristics of the forest roads were collected by combining the FMPs data coming from WOCAS v2 and a Digital Elevation Model (DEM) in a Geographic Information System (GIS) software. The georeferenced stands were characterized by both single contiguous areas (single stands), as well as different non-contiguous areas (sub-stands). Overall, 2157 polygons – consisting of both single and sub-stands – were analyzed, covering the period from 2009 (most recent available data on forest roads’ transitability) and 2016.
The mass of potentially available residues calculated for the analyzed period was used to estimate the current sustainable supply (i.e., 1.82∙103±6.61∙102 t·yr-1 DM). Under the hypothesis that these residues were prepared into woodchips to feed the Organic Rankine Cycle (ORC) unit of the local centralized heating plant of Ponte di Legno, the potentially generated heat and electricity (GJ·yr-1) and the potentially avoided CO2 emissions into the atmosphere (t∙yr-1 CO2) for the final combustion process were estimated by assuming that: (i) heat generated by the ORC unit replaced the one produced by natural gas-based heating plants; (ii) electricity generated by the ORC unit replaced the one generated by the Italian natural gas-based plants-mix for combined heat and electricity production and distributed through the National grid. Results showed that if only the current sustainable mass of residues was used to feed the ORC unit of the plant, the potentially generated heat and electricity would represent at most 28.7% of that generated by the unit in the year 2019. The thermal and electric power would be equal to 0.70 MW and 0.17 MW, with an average power load of the ORC unit of 23.6%.
Experimental tests are needed to collect information on the harvesting method, used machines and technologies – which considerably affect the mass of available resides – as well as the currently harvested mass of residues for the validation of the results, that up to now is not possible since no measured data are available yet at the stand level.
The second topic (forestry mechanization) is investigated in chapter 6. The aim is to develop an innovative approach in order to: (i) select the most suitable Forestry Machinery Chain (FMC) to adopt at the stand level for wood collection (harvesting and transport) and (ii) compute the economic costs (€·h-1; €·t-1 DM; €) of the selected FMC.
To make the selection feasible, a user-friendly stand-level model called “FOREstry MAchinery chain selection” (FOREMA v1) was developed. FOREMA v1 supports the user in selecting the FMC according to seven technical parameters that characterize the stand. For each FMC, the model defines the sequence of the operations and the types of machines that can be used. The economic costs of the selected FMC are then quantified by taking into account the fixed and the variable costs. The approach was applied for a Case Study concerning the collection of woodchips from a coppice stand in the Italian Alps for energy generation. The analyzed FMC was made up of the following operations: (i) felling, (ii) bunching and extraction, (iii) chipping and (iv) loading and transport. For the whole FMC, the cost per unit of time was 669.3 €·h-1; the cost per unit of product was 113.0 €·t DM, whereas the cost of production amounted to 6893.2 €. Results provided by FOREMA v1 still need to be validated; experimental tests are required to collect information on the operating conditions in which the machines are actually used and, consequently, on the corresponding economic costs. Obtained results on the costs of the operations were compared with that reported in literature and related to studies performed under similar forestry and operating conditions
High Accuracy Site-Specific Secondary Data for Mechanical Field Operations to Support LCA Studies
No full textThe aim of the study was to quantify site-specific secondary data of mechanical field operations for EU barley cropping. By the model ENVIAM v2, each operation was subdivided into 13 working times and, for each of them, the amount of total consuming inputs (fuel, lubricant and AdBlue®) and emissions of exhaust gases into the atmosphere were calculated. The amount of partial consuming inputs (machinery mass) and emissions of heavy metals into the soil were also quantified. Three scenarios (S) were identified: S1 = 50 ha, S2 = 100 ha, S3 = 200 ha, with the same: agronomic conditions, operations sequence, type of machines used and cropping inputs. For each scenario, two barley ideotypes were analyzed: (i) currently in use (BarNow, 2018) and (ii) future (BarPlus, 2030). BarPlus is characterized by: (i) higher grain and straw yield, Nitrogen fertilization rate and machinery Effective Field Capacity, (ii) use of TIER 5 fuel engines, (iii) lower specific minimum fuel consumption. BarNow inputs (kg·ha−1) were: fuel = 67 ÷ 74, lubricant = 0.56 ÷ 0.73, mass = 7.9 ÷ 8.8. BarPlus inputs (kg·ha−1) were: fuel = 55 ÷ 60, lubricant = 0.53 ÷ 0.69, AdBlue® = 2.8 ÷ 3.0, mass = 7.2 ÷ 8.0. The highest fuel and mass consumptions were in both cases related to tillage operations
Assessment of forest biomass and carbon stocks at stand level using site-specific primary data to support forest management
No full text[10.3] To estimate wood biomass (WB) and carbon (C) stocks of forests, several models have been developed; they differ in terms of details and scale of application. Stand level models are particularly important because stands represent the reference forest management units (FMU). The aims of the study were: (i) to assess WB and C stocks of Valle Camonica forests (Northern Italy) at stand level and (ii) to map the spatial distribution of these stocks
An assessment of the impact of possible CAP reform scenarios on Romanian agriculture
No full textUsing a simplified model, with key-variable the prices of two different possible scenarios of CAP reform after 2013 (moderate and radical), this paper present a comparison between the price effects of implementation of each reform scenario at 2015 horizon on Romanian agriculture. This short analysis shows that, under the presented hypotheses, the net welfare effect, due to the price changes, for the selected products, is positive in both reform scenarios, yet greater in the case of the radical reform. Integrated in the large context of Romanian development, it seems that the influence of CAP reform upon agriculture and rural areas will be most likely a gradual one: an interpenetration between the two scenarios is foreseeable, starting with the moderate reform that will dominate the period around 2013, the reform measures acquiring a more radical character afterwards.CAP reform, Romania, welfare effects, Agricultural and Food Policy,
Project FACCE-JPI "Modifying canopy architecture and photosynthesis to maximize barley biomass and yield for different end-uses (BARPLUS)". III meeting 8th - 9th March 2018, Lleida (Spain). WP4 - Task 4.3: Environmental Assessment - preliminary results
No full textA Preliminary Model for Forestry Machinery Chain Selection and Calculation of Operating Costs for Wood Recovery
No full textSelecting the most suitable machines to use for wood recovery is essential for computing
the operating costs of the whole forestry machinery chain (FMC). Nevertheless, a generalized
approach for selecting the most suitable FMC and quantifying the corresponding
economic performances for wood recovery (i.e., harvesting and long-distance transport)
is still missing. The primary aim of this study is to describe a decision support model,
called FOREstry MAchinery chain selection (“FOREMA v1”), which is able to (i) select the
most feasible FMC and (ii) calculate the costs (such as EUR·h−1; EUR·t−1 of dry matter,
DM) of each operation (OP) comprising the FMC. The model is made up of three different
modules (Ms): machinery chain selection (M1), machinery chain organization (M2), and
cost calculation (M3). In M1, feasible FMCs are defined according to seven technical parameters
that characterize the forest area. For each FMC, FOREMA v1 defines the sequence
of OPs and the types of machines that can potentially be used. Once the characteristics
of the area in which wood recovery occurs are processed, the user selects the types of
machines to use according to the model’s suggestions. In M2 and M3, the user is supported
in organizing the FMC (e.g., calculation of the required time, working productivity, and so
on) and computing the operating costs. The secondary aim of this study is to discuss a case
study focused on chips production for energy generation, providing empirical evidence
on how FOREMA v1 works. The proposed model provides a systematic approach for the
selection and optimization of the most suitable FMC to adopt for biomass recovery, thus
supporting decision-making processes. The results showed that felling had the lowest
cost per unit of time (63.7 EUR·h−1) but the highest cost per unit of mass (35.4 EUR·t
DM−1) due to its longer working time and lower productivity. Loading and long-distance
transport incurred the highest costs both per unit of time (223.5 EUR·h−1) and per unit
of mass (29.4 EUR·t DM−1), attributed to the use of medium–small-sized trailers coupled
with tractors operating at low speeds, leading to a high number of cycles. For the entire
FMC the costs were equal to 147.3 EUR·h−1 and 101.1 EUR·t DM−
Rich, Sturmian, and trapezoidal words
No full textIn this paper we explore various interconnections between rich words, Sturmian words, and trapezoidal words. Rich words, first introduced by the second and third authors together with J. Justin and S. Widmer, constitute a new class of finite and infinite words characterized by having the maximal number of palindromic factors. Every finite Sturmian word is rich, but not conversely. Trapezoidal words were first introduced by the first author in studying the behavior of the subword complexity of finite Sturmian words. Unfortunately this property does not characterize finite Sturmian words. In this note we show that the only trapezoidal palindromes are Sturmian. More generally we show that Sturmian palindromes can be characterized either in terms of their subword complexity (the trapezoidal property) or in terms of their palindromic complexity. We also obtain a similar characterization of rich palindromes in terms of a relation between palindromic complexity and subword complexity
Assessment of Forest Biomass and Carbon Stocks at Stand Level Using Site-Specific Primary Data to Support Forest Management
No full textTo quantify and map woody biomass (WB) and forest carbon (C) stocks, several models were developed. They differ in terms of scale of application, details related to the input data required and outputs provided. Local Authorities, such as Mountain Communities, can be supported in sustainable forest planning and management by providing specific models in which the reference unit is the same as the one reported in the Forest Management Plans (FMP), i.e. the forest stand. In the Lombardy Region (Northern Italy), a few studies were performed to assess WB and forest C stocks, and they were generally based on data coming from regional—or national—forest inventories and remote sensing, without taking into account data collected in the FMPs. For this study, the first version of the stand-level model “WOody biomass and Carbon ASsessment” (WOCAS) for WB and C stocks calculation was improved into a second version (WOCAS v2) and preliminary results about its first application to 2019 forest stands of Valle Camonica District (Lombardy Region) are presented. Since the model WOCAS uses the growing stock as the main driver for the calculation, it can be applied in any other forest area where the same input data are available
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