Términos relacionados

15 resultados encontrados para: AUTOR: Olguín Álvarez, Marcela Itzel
Índice | Resumen en: Inglés |
Resumen en inglés

FAO, in cooperation with its member countries, has monitored the world’s forests at five to ten year intervals since 1946. These global assessments provide valuable information to policy-makers, to international negotiations, arrangements and organizations related to forests and to the general public. The Global Forest Resources Assessment 2010 (FRA 2010) is the most comprehensive assessment to date. It examines the current status and recent trends for more than 90 variables and all types of forests in 233 countries and areas for four points in time: 1990, 2000, 2005 and 2010. FAO worked closely with countries and forest assessment specialists in the design and implementation of FRA 2010. More than 900 contributors were involved, including 178 officially nominated national correspondents and their teams. In the main section of this report, results are presented according to the seven thematic elements of sustainable forest management: • extent of forest resources; • forest biological diversity; • forest health and vitality; • productive functions of forest resources; • protective functions of forest resources; • socio-economic functions of forests; • legal, policy and institutional framework. A summary of key findings is presented below, followed by a section that attempts to answer the question: What does FRA 2010 tell us about progress towards sustainable forest management since 1990 at global and regional scales?

KEY FINDINGS Forests cover 31 percent of total land area The world’s total forest area is just over 4 billion hectares, which corresponds to an average of 0.6 ha per capita (Figure 1). The five most forest-rich countries (the Russian Federation, Brazil, Canada, the United States of America and China) account for more than half of the total forest area. Ten countries or areas have no forest at all and an additional 54 have forest on less than 10 percent of their total land area (Figure 2). The rate of deforestation shows signs of decreasing, but is still alarmingly high Deforestation – mainly the conversion of tropical forest to agricultural land – shows signs of decreasing in several countries but continues at a high rate in others (Boxes 1–3). Around 13 million hectares of forest were converted to other uses or lost through natural causes each year in the last decade compared with 16 million hectares per year in the 1990s. Both Brazil and Indonesia, which had the highest net loss of forest in the 1990s, have significantly reduced their rate of loss, while in Australia, severe drought and forest fires have exacerbated the loss of forest since 2000. Large-scale planting of trees is significantly reducing the net loss of forest area globally Afforestation and natural expansion of forests in some countries and regions have reduced the net loss of forest area significantly at the global level (Figure 4). The net change in forest area in the period 2000–2010 is estimated at -5.2 million hectares per year (an area about the size of Costa Rica), down from -8.3 million hectares per year in the period 1990–2000.

South America and Africa continue to have the largest net loss of forest At a regional level, South America suffered the largest net loss of forests between 2000 and 2010 – about 4.0 million hectares per year – followed by Africa, which lost 3.4 million hectares annually (Figure 5). Oceania also reported a net loss of forest (about 700 000 ha per year over the period 2000–2010), mainly due to large losses of forests in Australia, where severe drought and forest fires have exacerbated the loss of forest since 2000. The area of forest in North and Central America was estimated as almost the same in 2010 as in 2000. The forest area in Europe continued to expand, although at a slower rate (700 000 ha per year) than in the 1990s (900 000 ha per year). Asia, which had a net loss of forest of some 600 000 ha annually in the 1990s, reported a net gain of forest of more than 2.2 million hectares per year in the period 2000–2010, primarily due to the large-scale afforestation reported by China and despite continued high rates of net loss in many countries in South and Southeast Asia.Forests store a vast amount of carbon Estimates made for FRA 2010 show that the world’s forests store 289 gigatonnes (Gt) of carbon in their biomass alone. While sustainable management, planting and rehabilitation of forests can conserve or increase forest carbon stocks, deforestation, degradation and poor forest management reduce them. For the world as a whole, carbon stocks in forest biomass decreased by an estimated 0.5 Gt annually during the period 2005–2010, mainly because of a reduction in the global forest area (Figure 6).

Primary forests account for 36 percent of forest area – but have decreased by more than 40 million hectares since 2000 On a global average, more than one-third of all forest is primary forest, i.e. forest of native species where there are no clearly visible indications of human activities and the ecological processes have not been significantly disturbed (Figure 7). Primary forests, in particular tropical moist forests, include the most species-rich, diverse terrestrial ecosystems. The decrease of primary forest area, 0.4 percent annually over a ten-year period, is largely due to reclassification of primary forest to ‘other naturally regenerated forest’ because of selective logging and other human interventions. The area of planted forest is increasing and now accounts for 7 percent of total forest area Forests and trees are planted for many purposes and make up an estimated 7 percent of the total forest area, or 264 million hectares. Between 2000 and 2010, the area of planted forest increased by about 5 million hectares per year (Figure 8). Most of this was established through afforestation (i.e. planting of areas not forested in recent times) particularly in China. Three-quarters of all planted forests consist of native species while one-quarter comprises introduced species (Figure 9). Twelve percent of the world’s forests are designated for the conservation of biological diversity The area of forest where conservation of biological diversity is designated as the primary function has increased by more than 95 million hectares since 1990, of which the largest part (46 percent) was designated between 2000 and 2005 (Figure 10). These forests now account for 12 percent of the total forest area or more than 460 million hectares. Most but not all of them are located inside protected areas.

Legally established protected areas cover an estimated 13 percent of the world’s forests National parks, game reserves, wilderness areas and other legally established protected areas cover more than 10 percent of the total forest area in most countries and regions (Figure 11). The primary function of these forests may be the conservation of biological diversity, the protection of soil and water resources, or the conservation of cultural heritage. The area of forest within a protected area system has increased by 94 million hectares since 1990. Two-thirds of this increase has been since 2000. Forest fires are severely underreported at the global level While some forest ecosystems depend on fire for their regeneration, in others forest fires can be devastating and also frequently cause loss of property and human life. On average, 1 percent of all forests were reported to be significantly affected each year by forest fires. However, the area of forest affected by fires was severely underreported, with information missing from many countries, especially in Africa. Less than 10 percent of all forest fires are prescribed burning; the rest are classified as wildfires.

Insect pests and diseases, natural disasters and invasive species are causing severe damage in some countries Outbreaks of forest insect pests damage some 35 million hectares of forest annually, primarily in the temperate and boreal zone. The mountain pine beetle has devastated more than 11 million hectares of forest in Canada and the western United States of America since the late 1990s – an unprecedented outbreak exacerbated by higher winter temperatures. Severe storms, blizzards and earthquakes have also damaged large areas of forest since 2000. Woody invasive species are of particular concern in small island developing states, where they threaten the habitat of endemic species. Information availability and quality continues to be poor for most of these disturbances. Thirty percent of the world’s forests are primarily used for production of wood and non-wood forest products Close to 1.2 billion hectares of forest are managed primarily for the production of wood and non-wood forest products. An additional 949 million hectares (24 percent) are designated for multiple use – in most cases including the production of wood and non-wood forest products. The area designated primarily for productive purposes has decreased by more than 50 million hectares since 1990 as forests have been designated for other purposes. The area designated for multiple use has increased by 10 million hectares in the same period. Wood removals increased between 2000 and 2005, following a fall in the 1990s At the global level, reported wood removals amounted to 3.4 billion cubic metres annually in the period 2003–2007, similar to the volume recorded for 1990 and equivalent to 0.7 percent of the total growing stock (Figure 12). Considering that informally and illegally removed wood, especially woodfuel, is not usually recorded, the actual amount of wood removals is undoubtedly higher. At the global level, woodfuel accounted for about half

Eight percent of the world’s forests have protection of soil and water resources as their primary objective Around 330 million hectares of forest are designated for soil and water conservation, avalanche control, sand dune stabilization, desertification control or coastal protection. The area of forest designated for protective functions increased by 59 million hectares between 1990 and 2010, primarily because of large-scale planting in China aimed at desertification control, conservation of soil and water resources and other protective purposes. The management of forests for social and cultural functions is increasing, but the area is difficult to quantify The only subregions and regions with fairly good data on the designation of forests for recreation, tourism, education or conservation of cultural and spiritual heritage are East Asia and Europe, where provision of such social services was reported as the primary management objective for 3 and 2 percent of the total forest area, respectively. Brazil has designated more than one-fifth of its forest area for the protection of the culture and way of life of forest-dependent people. Globally, 4 percent of the world’s forests are designated for the provision of social services. The value of wood removals is high, but fluctuating Wood removals valued just over US$100 billion annually in the period 2003–2007, mainly accounted for by industrial roundwood. At the global level the reported values show no change between 1990 and 2000, but an increase of about 5 percent annually over the period 2000–2005, suggesting that roundwood prices recovered somewhat since their decline (in real terms) in the decade 1990–2000 (Figure 13). However, they have since fallen sharply.

The value of non-wood forest products remains underestimated The reported value of non-wood forest product removals amounted to about US$18.5 billion in 2005. Food products accounted for the greatest share. However, information is still missing from many countries in which non-wood forest products are highly important, and the true value of subsistence use is rarely captured. As a result, the reported statistics probably cover only a fraction of the true total value of harvested non-wood forest products. Around 10 million people are employed in forest management and conservation – but many more are directly dependent on forests for their livelihoods Reported employment in forest establishment, management and use declined by about 10 percent between 1990 and 2005, probably because of gains in labour productivity. Europe, East Asia and North America saw steep declines (15 to 40 percent between 1990 and 2005), while in other regions, employment increased somewhat – probably because roundwood production has increased faster than gains in labour productivity. Most countries reported increased employment in management of protected areas. Given that much forestry employment is outside the formal sector, forest work is surely much more important for rural livelihoods and national economies than the reported figures suggest.

Governments generally spend more on forestry than they collect in revenue On average, total forest revenue collection was about US$4.5 per hectare, ranging from under US$1 per hectare in Africa to just over US$6 per hectare in Europe (Figure 14). Public expenditure on forestry was about US$7.5 per hectare on average. Average expenditure was highest in Asia (over US$20 per hectare). In contrast, the average expenditure per hectare was less than US$1 in South America and Oceania (Figure 15). Significant progress has been made in developing forest policies, laws and national forest programmes Of the 143 countries that have a forest policy statement, 76 countries have issued or updated their statements since 2000. Of the 156 countries that have a specific forest law, 69 countries – primarily in Europe and Africa – reported that their current forest law has been enacted or amended since 2005. Close to 75 percent of the world’s forests are covered by a national forest programme, i.e. a participatory process for the development and implementation of forest-related policies and international commitments at the national level (Figure 16). Staff numbers in public forest institutions are decreasing Around 1.3 million people were reported to work in public forest institutions in 2008, 22 percent of whom were female. At the global level, the number of staff has declined by 1.2 percent annually since 2000. More than 20 000 professionals work in public forest research institutions. The number of university students graduating in forestry is increasing More than 60 000 university students graduate in forestry annually. This equates to about 1 per 86 000 inhabitants, or around 200 per 10 million hectares of forests. Onethird of graduating students are female, and this proportion is increasing.

Eighty percent of the world’s forests are publicly owned, but ownership and management of forests by communities, individuals and private companies is on the rise Despite changes in forest ownership and tenure in some regions, most of the world’s forests remain under public ownership (Figure 17). Differences among regions are considerable. North and Central America, Europe (other than the Russian Federation), South America and Oceania have a higher proportion of private ownership than other regions. In some regions, there is an increasing trend toward involving communities, individuals and private companies in the management of publicly owned forests (Figure 18). Forests are managed for a multitude of uses and values Forests are increasingly being conserved and managed for multiple uses and values – often in combination (Figure 19). Around 949 million hectares, or 24 percent of all forests, are designated for multiple use, i.e. managed for any combination of the production of goods, protection of soil and water, conservation of biodiversity and provision of social services – or where none of these alone is considered as the predominant function. More than 1.6 billion hectares of forest have a management plan The area of forest covered by a management plan – an important tool for achieving sustainable forest management – is steadily increasing, yet information is only available for 80 percent of the total forest area (Figure 20). For the first time, information was also collected on the area of forest under sustainable forest management (Box 4).

PROGRESS TOWARDS SUSTAINABLE FOREST MANAGEMENT To obtain a broad picture of progress towards sustainable forest management, a subset of indicators was selected for each of the seven thematic elements of sustainable forest management and data on trends were compiled and compared at global, regional and subregional levels across the seven themes. The results are summarized below and illustrated in Tables 1 and 2. For more information, refer to Chapter 9. Progress towards sustainable forest management at the global level Overall, the situation at the global level has remained relatively stable over the last 20 years (Table 1). The change in forest area is well below the threshold of 0.5 percent per year for a significant change. The largest negative rates (in percentage terms) include the decrease in the area of primary forest over the entire 20-year period; in wood removals and employment in the 1990s; and in human resources in public forest institutions during the period 2000–2005. Significant positive trends were reported in the area of forest designated for the conservation of biological diversity and the area of forest in protected areas (particularly in the last decade), the area of planted forest and the number of students graduating in forestry. Forests under private ownership and the value of wood products showed a positive trend for the period 2000–2005.

Progress at regional levels Africa. On the whole, progress towards sustainable forest management in Africa has improved when comparing the last decade to the 1990s. The net loss of forest area has slowed down, and the areas of forest designated for the conservation of biological diversity and included in protected areas have increased slightly. The sharp increase in the area of forest with a management plan over the last ten years is particularly good news. The continued, rapid loss of forest area (the second largest of any region during this 20-year period) is, however, still a cause for concern as is the loss of primary forests. A summary of information by subregion can be found in Table 2. Asia. Overall the forest area in Asia is about 16 million hectares larger in 2010 than it was in 1990 as a result of large-scale afforestation efforts during the last 10–15 years, particularly in China. The decrease in area of primary forest is cause for concern, while the increase in the forest area designated for conservation of biological diversity, the area of forest in protected areas and forests designated for protective functions is commendable. The area affected by fire decreased while that affected by insects increased sharply between 1990 and 2000, but then levelled off. Variables representing the legal, policy and institutional framework are largely positive or stable and information availability in the region is generally good. In short, there has been mixed progress over the last 20 years at the regional level with large variations between countries and subregions. A summary of information by subregion can be found in Table 2.

Europe. Data availability was generally high for Europe, although results were strongly influenced by the Russian Federation. The status of forest resources in Europe has essentially been stable over the last 20 years. While the area of forest is expanding, the focus of forest management in Europe has clearly shifted away from productive functions towards conservation of biological diversity, protection and multiple uses – a shift already evident at the end of the 1990s. The main negative trends are found in employment and – when analysing figures excluding the Russian Federation – in human resources in public forest institutions between 2005 and 2008, as well as in the value of wood removals in the 1990s. Table 2 shows the trends for Europe including and excluding the Russian Federation. North and Central America. Progress towards sustainable forest management was generally positive in North and Central America as a whole during the period 1990–2010, with the notable exception of the significant negative trends noted for the area of forest affected by fire and by insect pests and the slight decrease in the level of employment. There was, however, considerable variation among subregions, as can be seen in Table 2.

Oceania. Data availability is largely determined by Australia, since it accounts for 78 percent of the forest area in this region. With information missing from Australia for 1990 for many of these variables it is impossible to assess long-term trends in this region for most of the themes. The loss of primary forest and the increase in the net loss of forest area in the region are cause for concern, despite the fact that part of the loss of forest area may be a temporary loss of forest cover due to an extensive drought in Australia. South America. Overall, progress towards sustainable forest management was mixed in South America. The rate of net forest loss continues to be a cause for concern although significant progress has been made, particularly in the last five years. The rate of loss of primary forest also remains alarmingly high. Nonetheless, there were also positive signs in the increased areas of forest designated for conservation of biological diversity and in protected areas. The decrease in removals of woodfuel may reflect a reduced demand for this product in the region, but this was partly offset by an increase in removals of industrial wood since 2000. The area of planted forests increased and may meet a larger proportion of the demand for wood in the future. The increase in the area of forest with a management plan is also a positive sign.

Is there progress towards sustainable forest management? There are many good signs and positive trends at the global level, particularly in the last ten years, but many negative trends remain at regional, subregional and national levels. While the area of planted forest and conservation efforts are on the rise, the area of primary forests continues to decline at an alarming rate as these forests come under use or are converted to other uses. As the analyses above illustrate, the answer depends on the suite of indicators selected and the scale at which they are applied. Given this and the complexity of the question, the answer cannot be definitive. NEXT STEPS Members of the Collaborative Partnership on Forests (CPF), regional groups, nongovernmental organizations and countries worked together in the design and implementation of FRA 2010. Joint planning for the next global assessment (FRA 2015) will commence in 2011 based on an in-depth evaluation of FRA 2010.


Acronyms and abbreviations
Executive summary xiii
Chapter 1. Introduction
The reporting framework
The scope of FRA 2010
The process
The outputs
Chapter 2. Extent of forest resources
Key findings
Key conclusions
Forest area and forest area change
Forest characteristics
Selected forest types and species groups
Growing stock
Carbon stock
Chapter 3. Forest biological diversity
Key findings
Key conclusions
Area of primary forests
Forest area designated for conservation of biological diversity
Area of forest in protected areas
Tree species composition
Chapter 4. Forest health and vitality
Key findings
Key conclusions
Insects and diseases
Forest fires
Other disturbances
Chapter 5. Productive functions of forest resources
Key findings
Key conclusions
Areas designated for productive functions
Planted forests
Afforestation and reforestation
Removals of wood products
Removals of non-wood forest products
Chapter 6. Protective functions of forest resources
Key findings
Key conclusions
Forest area designated for protective purposes
Chapter 7. Socio-economic functions of forest resources
Key findings
Key conclusions
Ownership and management rights
Public expenditure and revenue collection
Value of wood and non-wood forest product removals
Area of forest designated for social services
Chapter 8. Legal, policy and institutional framework
Key findings
Key conclusions
Policy and legal framework
Institutional framework
Education and research
Chapter 9. Progress towards sustainable forest manageme

Greenhouse gas emissions between 1993 and 2002 from land-use change and forestry in Mexico
De Jong, Bernardus Hendricus Jozeph ; Carlos, Carlos (coaut.) ; Masera Cerutti, Omar Raúl (coaut.) ; Olguín Álvarez, Marcela Itzel (coaut.) ;
Contenido en: Forest Ecology and Management Vol. 260, no. 10 (October 2010), p. 1689-1701 ISSN: 0378-1127
Resumen en: Inglés |
Resumen en inglés

In this paper we present the Mexican inventory of greenhouse gas (GHG) emissions from the land-use sector. It involved integration of forest inventory, land-use and soil data in a GIS to estimate the net flux of GHG between 1993 and 2002. The net GHG flux of 86.9 (±34.4%) Tg CO2 y−1 resulted from the balance of emissions of 64.5 (±12%) Tg CO2 y−1 from biomass loss, 4.9 (±259%) Tg CO2 y−1 from managed forests, and 30.3 (±106%) Tg CO2 y−1 from mineral soils, and the removals of 12.9 (±36%) Tg CO2 y−1 in abandoned lands. Main sources of uncertainty include lack of integrated soil and biomass data and the impact of the various management practices on biomass. Key factors are identified to improve GHG inventories and to reduce uncertainty.

Artículo - Nota científica con arbitraje
*En hemeroteca, SIBE-Campeche, SIBE-Villahermosa
El uso del suelo en el contexto de cambio climático: ¿parte del problema o de la solución?
Olguín Álvarez, Marcela Itzel ; Valle Doménech, Andrés (coaut.) ; Ochoa Gaona, Susana (coaut.) ; De Jong, Bernardus Hendricus Jozeph (coaut.) ;
Contenido en: Kuxulkab'. Revista de Divulgación Vol. XII, no. 24 (2007), p. 61-64 ISSN: 1665-0514
Bibliotecas: Campeche , Villahermosa
SIBE Campeche
51997-10 (Disponible)
Disponibles para prestamo: 1
SIBE Villahermosa
51997-20 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-Campeche, SIBE-Villahermosa

Tesis - Licenciatura
Incorporación de la captura de carbono como propuesta de manejo forestal integral: estudio de caso en una comunidad de la Meseta Purépecha, México / Marcela Itzel Olguín Alvarez
Olguín Álvarez, Marcela Itzel ; Vázquez Montes, Alejandro (director) ; Masera Cerutti, Omar Raúl (director) ;
México : Universidad Nacional Autónoma de México, Facultad de Ciencias , 2001
Clasificación: T/634.928 / O4
SIBE Campeche
ECO040003245 (Disponible)
Disponibles para prestamo: 1
SIBE San Cristóbal
ECO010007121 (Disponible)
Disponibles para prestamo: 1
SIBE Villahermosa
ECO050002992 (Disponible)
Disponibles para prestamo: 1