Reduced-Impact Logging (RIL) is a set of

forestry Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests and woodlands for associated resources for human and Natural environment, environmental benefits. Forestry is practiced in plantations and ...

practices which enable sustainability within tropical selective felling forestry. RIL is intensively planned and carefully controlled timber harvesting conducted by trained workers in ways that minimize the deleterious impacts of

logging Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucks

Selective logging In forestry, fishing and mining, high grading refers to the selective harvesting of goods to keep only the most valuable items. The term is frequently associated with fraud, especially in mining. Forestry In forestry, high grading, also sometimes ...

is a widely common timber-harvesting practice that involves the removal of few timbers species trees above a minimum diameter cutting limit. It is estimated that selective logging worldwide concerns 1 billion hectares of forests including 680 million hectares of tropical forests species. Unlike

clearcutting Clearcutting, clearfelling or clearcut logging is a forestry/logging practice in which most or all trees in an area are uniformly cut down. Along with Shelterwood cutting, shelterwood and Seed tree, seed tree harvests, it is used by foresters t ...

, where all trees in an area are felled, selective logging leaves the remaining trees in the stand. Selective logging plays a crucial role in the achievement of sustainable forest management practices. Its impacts depend a lot on the harvesting techniques employed and the amount of damage involved will have important consequences on the capacity of the forest to regenerate. Where forests are selectively logged by untrained and poorly supervised workers at intensities and frequencies that do not sustain timber yields, this causes high damage to the forest stand, hydrological functions and

biodiversity Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distribut ...

. Selective logging is justifiably referred as conventional or even predatory selective logging. Very early on, foresters have been trying to introduce harvesting techniques that caused as little damage as possible to the forest stand, soil and water system. However, the term 'Reduced Impact' better known now under its acronym RIL was raised only in the late 1990s.

History

Prior to

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, logging in tropical forests was primarily manual, with minimal environmental impacts due to extremely low harvest intensities. Early efforts to transform timber exploitation into forest management, such as Sir Dietrich Brandis's teak management system in Burma, emphasized careful logging to preserve future

timber Lumber is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, window frames). ...

resources. Despite this and other efforts, the post-war economic boom fueled a surge in global demands for tropical timber, leading to widespread and mostly uncontrolled industrial logging. Mechanized logging substantially expanded the scales and intensities of harvest operations, raising concerns about the increasingly degraded state of forests. By the early 1990s, it became evident that mechanized logging posed serious threats to long-term sustainability, particularly when considering non-timber values. Evidence was also accumulating that logging is among the world's most dangerous occupations. In response, the concept of RIL emerged to mitigate environmental damage while meeting timber needs. While most of the recommended RIL practices have long been known soon after the term was introduced, RIL gained acceptance and legitimacy, resonating with both foresters and environmental organizations. RIL (also known as reduced-impact harvesting, RIH or low-impact logging, LIL) has its roots in a long-standing recognition of the detrimental environmental effects of unplanned and so-called conventional logging. RIL is basically a set of recommended practices for selectively harvesting trees in a planned and controlled way by trained workers to minimize harm to the forest and risks to the workers. Despite advocacy for better logging practices by experts over the decades, widespread adoption of RIL remains adopted by only a small number of nations who legislate for this in their national forest standard such as

Gabon Gabon ( ; ), officially the Gabonese Republic (), is a country on the Atlantic coast of Central Africa, on the equator, bordered by Equatorial Guinea to the northwest, Cameroon to the north, the Republic of the Congo to the east and south, and ...

Republic of Congo The Republic of the Congo, also known as Congo-Brazzaville, the Congo Republic or simply the Congo (the last ambiguously also referring to the neighbouring Democratic Republic of the Congo), is a country located on the western coast of Central ...

and

Guyana Guyana, officially the Co-operative Republic of Guyana, is a country on the northern coast of South America, part of the historic British West Indies. entry "Guyana" Georgetown, Guyana, Georgetown is the capital of Guyana and is also the co ...

. There are pockets of sustainable RIL forestry in other tropical nations, proven by certification through

Forest Stewardship Council The Forest Stewardship Council GmbH (FSC) is an international non-profit, multistakeholder organization established in 1993 that promotes responsible management of the world's forests via timber certification. This organization uses a market-b ...

(FSC) and

Programme for the Endorsement of Forest Certification The Programme for the Endorsement of Forest Certification (PEFC) is an international, non-profit, non-governmental organization which promotes sustainable forest management through independent third-party certification. As of 2006, it was cons ...

(PEFC). The core principles of RIL involve a series of pre- and post-logging guidelines designed to minimize damage to forests and ecosystems. These guidelines include measures such as pre-harvest planning of skid trails and log yards, directional felling, and post-logging closure operations to mitigate soil damage and maintain ecosystem processes.Sist, P.; Dykstra, D.; & Fimbel, R. (1998). Reduced-impact logging guidelines for lowland and hill dipterocarp forests in Indonesia. Accumulating research has demonstrated the effectiveness of RIL techniques in reducing stand and soil damage compared to conventional logging. Influential publications and initiatives by organizations such as the Tropical Forest Foundation (TFF), the

International Tropical Timber Organization The International Tropical Timber Organization (ITTO) is an intergovernmental organization that promotes conservation of tropical forest resources and their sustainable management, use and trade. Organization The organization was established und ...

(ITTO), and the

Food and Agriculture Organization The Food and Agriculture Organization of the United Nations; . (FAO) is a specialized agency of the United Nations that leads international efforts to defeat hunger and improve nutrition and food security. Its Latin motto, , translates ...

(FAO) have played a significant role in the development of codes of practice for logging in tropical forests. In 1996, FAO published a model code of forest harvesting practice, which served as a guiding framework for many tropical countries to develop their own codes. These efforts aimed to promote sustainable forest management and reduce the environmental impacts of logging provided the groundwork for adoption of RIL practices globally. Despite progress in promoting RIL, challenges persist in achieving widespread adoption due to economic constraints, the lack of market demand for certified RIL timbers, and the continued influence of conventional logging norms. However, RIL remains a substantial step toward sustainable forest management and certification bodies such as FSC and PEFC are recognized as commercial vehicles towards ensuring RIL and sustainable forestry.

Management

RIL is a set of timber harvesting practices primarily focused on minimizing environmental damage. Its key goal is to harvest timber responsibly while also ensuring worker safety and preserving the forest for future use. Developed guidelines, influenced by initiatives like those from

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and the FAO, have been tailored for various tropical regions, such as Asia-Pacific,

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

, and

West West is one of the four cardinal directions or points of the compass. It is the opposite direction from east and is the direction in which the Sun sets on the Earth. Etymology The word "west" is a Germanic word passed into some Romance langu ...

and

Central Africa Central Africa (French language, French: ''Afrique centrale''; Spanish language, Spanish: ''África central''; Portuguese language, Portuguese: ''África Central'') is a subregion of the African continent comprising various countries accordin ...

. The core of RIL involves accurate forest inventories followed by careful planning and management practices to sustain forest ecosystems. These practices include assigning forest management units and coupes, excluding sensible areas (steep slopes, buffer zones around rivers and swamp areas) from logging, meticulously planning access roads and log landings, and conducting thorough post-harvest assessments. A critical aspect of RIL is the protection of future crop trees (FCTs), minimizing wood waste and ensuring worker safety, with specific practices varying with ecological conditions and logging techniques. Key RIL practices include conducting detailed pre-harvest inventories that include marking FCTs, reducing soil damage especially on steep slopes, and cutting

lianas A liana is a long-Plant stem, stemmed Woody plant, woody vine that is rooted in the soil at ground level and uses trees, as well as other means of vertical support, to climb up to the Canopy (biology), canopy in search of direct sunlight. T ...

well before harvesting to enhance safety and reduce stand damage. The FAO advocated for broader adoption of RIL by producing a model code of forest harvesting practice, which emphasizes several standard measures: defining a minimum cutting cycle of 20 years, limiting the removal of stand basal area to one-third, directional felling to facilitate log yarding, and limiting the size of log landings. Moreover, it recommends building access roads and cutting vines well in advance of harvesting, planning skid trails to minimize their impacts, performing logging activities only under favorable conditions such as dry soils, and providing thorough training for staff. Lastly, it stresses the importance of conducting post-harvest assessments to gauge the impacts and effectiveness of logging practices. Despite these comprehensive guidelines, standardizing damage assessment methods across different regions remains a challenge, with ongoing efforts to enhance consistency and biological relevance in forest management practices.

Ecology

Use of RIL practices results in fewer trees and less soil being damaged, but its benefits can be lost at very high logging intensities. What is crucial is that each country establishes its logging rate depending on density of species. There is not one blanket rule for logging levels in all tropical forests. In

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

, researchers have provided evidence that when more than 8 trees per hectare are logged, the benefits of RIL are diminished and the impacts become similar to those from conventional logging. High logging intensities also affect the sustainability of timber yields, as removing too many trees leaves behind a forest with too few FCTs to maintain timber yields within the usual 25-35-year cycles in tropical forests; 60 years in Guyana for large concessions. Forests in every part of the tropical region will vary in density of species. That is why RIL is so important and a uniform rule cannot be applied across all tropical areas as the species are different in the forest mix. Each forest needs to be looked at in its own right and evaluated by the growth rate of species within that forest. RIL and inventory planning ensures this by considering growth rates of each species in the mix. The recovery of commercial timber volume after RIL depends substantially on how much damage the logging causes; heavily damaged areas often see a slower recovery because vines and fast-growing pioneer species dominate, which can hinder the growth of valuable timber trees. Biomass recovery is also slower when logging intensity is high, as more trees are destroyed or damaged, reducing the forest's ability to regenerate. RIL techniques hold promise for minimizing the ecological damage from logging activities. Yet, understanding its impact on biodiversity remains limited, with emerging scientific evidence focusing on a few taxa. For example, there is evidence that RIL minimizes negative impacts on stream habitats, amphibian occupancy, and diversity compared to conventional logging (CL), while also facilitating faster recovery. Studies comparing RIL with CL have found limited evidence for major differences in biodiversity impacts, at least over the short term. As an example, a study in Guyana compared

vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...

populations in areas subjected to RIL and adjacent unlogged sites. While large

frugivores A frugivore ( ) is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance ...

such as primates were less abundant in RIL sites, smaller frugivores, granivores,

folivores In zoology, a folivore is a herbivore that specializes in eating leaves. Mature leaves contain a high proportion of hard-to-digest cellulose, less energy than other types of foods, and often toxic compounds.Jones, S., Martin, R., & Pilbeam, D. (1 ...

, and

insectivores A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...

were more common. Three of the 15 vertebrate species examined changed in abundance, with two showing negative impacts due to RIL. A meta-analysis revealed that species abundance shifts are smaller under RIL, with fewer detrimental effects on

birds Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

arthropods Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

, and

mammals A mammal () is a vertebrate animal of the class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three middle e ...

. The reduced impact is attributed to better logging practices, such as planned logging roads, pre-harvest inventories, and directional felling, which minimize forest damage. While forests subjected to low intensity RIL retain the overall structure and composition of unlogged stands, they typically do not fully recover to pre-logging levels of biodiversity. A meta-analysis showed that RIL can reduce tree damage compared to CL, its impacts on tree species richness vary with logging intensity. While RIL can reduce

carbon emissions Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide (), from burning fossil fuels such as coal, petroleum, oil, and natural gas, is the main cause of climate chan ...

by enhancing logging efficiency and protecting sensitive habitats without sacrificing timber yields, its effects on biodiversity are less clear. Long-term effects on biodiversity are uncertain, necessitating further research with appropriate controls and long-term monitoring. Despite uncertainties about its direct effects on biodiversity, RIL may indirectly contribute to biodiversity conservation by increasing the economic value of selectively logged forests. This could help prevent forest conversion to agricultural plantations, thereby preserving habitat for forest-dependent species. RIL may thus serve as a valuable conservation strategy in combating

deforestation Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...

and

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

Economy

RIL presents both challenges and opportunities from an economic perspective. Whether it imposes a financial burden on loggers remains a contentious issue, with concerns about reduced income and increased operational costs apparently hindering widespread adoption. Loggers transitioning to RIL often face the need for new equipment, safety measures, and trained personnel, which all add to operational expenses. On the other hand, there is also evidence that due to increased recovery of timber from felled trees and other efficiencies derived from planning and the professionalization of harvest crews, RIL can also be financially remunerative. The economic viability of RIL compared to CL varies widely with factors such as forest conditions, terrain, labor practices, and timber markets. Studies have produced mixed results, with some showing RIL to be financially favorable due to reduced timber wastage, while others highlight potential losses, especially in areas with restrictions on harvesting.

Market access

Different stakeholders, including forest owners, timber companies, forest workers, and logging contractors, may have conflicting perspectives on the financial implications of RIL. Long-term consequences, such as environmental sustainability and worker safety, are often weighed differently by various parties. While RIL guidelines are often designed with larger industrial operations in mind, they are also relevant for smallholder forestry. Smallholders can benefit from the reduced waste and increased safety that RIL promotes. However, some aspects of RIL may need to be adapted to meet the specific needs and constraints of smallholder operations. Tropical forests face increasing demands for timber,

non-timber forest products Non-timber forest products (NTFPs) are useful foods, substances, materials and/or commodities obtained from forests other than timber. Harvest ranges from wild collection to farming. They typically include game animals, fur-bearers, nuts, see ...

(NTFPs), and

ecosystem services Ecosystem services are the various benefits that humans derive from Ecosystem, ecosystems. The interconnected Biotic_material, living and Abiotic, non-living components of the natural environment offer benefits such as pollination of crops, clean ...

. As a result, there is a pressing need for further exploration of alternative use regimes and a comprehensive assessment of the costs and benefits for forest-dependent communities. Tools such as the RILSIM software package allow for detailed financial analysis of logging operations, aiding in decision-making and comparisons between RIL and CL. However, broader economic considerations, such as environmental benefits and externalities, are not always captured in traditional cost-benefit analyses. Despite challenges, there are potential economic benefits to RIL, including increased carbon retention and eligibility for environmental service payments. As international markets for carbon, hydrological services, and biodiversity continue to develop, forests managed with RIL techniques may gain recognition and financial incentives for their conservation efforts. The reduced-impact logging for climate change mitigation (RIL-C) protocol is an important method for monitoring carbon emissions from selective logging operations. Developed in response to concerns about climate change, the RIL-C methodology provides a standardized approach to measure carbon emissions caused by tree felling, skidding, and hauling. The protocol separates emissions from these activities, allowing for more precise measurement and monitoring. For example, studies have shown that adopting RIL-C can reduce logging emissions by up to 44%, primarily through changes such as narrower haul roads, improved skid trail planning, and better felling techniques. The RIL-C approach is also relevant in the context of carbon markets and climate agreements like

REDD+ REDD+ is a voluntary climate mitigation framework developed by the United Nations Framework Convention on Climate Change (UNFCCC). It aims to encourage developing countries to reduce greenhouse gas emissions and deforestation, enhance forest's ...

and the

Paris Climate Accord The Paris Agreement (also called the Paris Accords or Paris Climate Accords) is an international treaty on climate change that was signed in 2016. The treaty covers climate change mitigation, Climate change adaptation, adaptation, and Climate ...

. Emission savings from RIL practices, monitored with the RIL-C protocol, can help countries achieve their climate change goals. These savings may also qualify for carbon payments, encouraging the adoption of sustainable practices. In Central Africa, implementation of the RIL-C protocol has shown that over 50% of logging emissions could be avoided without reducing timber yields. This makes RIL-C a practical approach for environmental conservation while supporting climate mitigation efforts.

Organizations

This section highlights key institutions that have played a crucial role in developing guidelines for and promoting RIL.

Food and Agriculture Organization (FAO)

The

FAO The Food and Agriculture Organization of the United Nations; . (FAO) is a List of specialized agencies of the United Nations, specialized agency of the United Nations that leads international efforts to defeat hunger and improve nutrition ...

is a

United Nations The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...

agency dedicated to

agriculture Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created ...

, and

fisheries Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place ( a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish farm ...

. It was instrumental in developing the model code of forest harvesting practice for RIL, aiming to align harvesting techniques with sustainable forest management objectives. This effort enhances the compatibility of logging practices with the broader goals of sustainable development, thereby supporting both economic and social aims.

International Tropical Timber Organization (ITTO)

The ITTO is an

intergovernmental agency An international organization, also known as an intergovernmental organization or an international institution, is an organization that is established by a treaty or other type of instrument governed by international law and possesses its own leg ...

dedicated to promoting the sustainable management of tropical forests and fostering international trade in tropical timber sourced from sustainably managed and legally harvested forests. ITTO has been instrumental in developing guidelines and principles for RIL to minimize environmental damage while maintaining economic viability. The organization assists member countries in adapting these RIL guidelines to local conditions through projects and capacity-building initiatives. Additionally, ITTO maintains a comprehensive database of RIL projects, providing valuable insights and data on the implementation and effects of these practices. It also focuses on implementing policy guidelines to support sustainable forest management and sustainable tropical timber trade, collects and disseminates data on tropical timber production and trade, promotes sustainable timber supply chains, and supports capacity building in tropical forestry.

Tropical Forest Foundation (TFF)

The TFF is an international non-profit educational

NGO A non-governmental organization (NGO) is an independent, typically nonprofit organization that operates outside government control, though it may get a significant percentage of its funding from government or corporate sources. NGOs often focus ...

committed to tropical forest conservation through sustainable forestry practices. Recognized for its demonstration models and training courses, TFF specializes in teaching sustainable forest management principles, particularly RIL. In Southeast Asia and the Pacific, particularly Indonesia, TFF focuses on practical RIL training upon request, while also addressing legality, market connections, and certification support.

Association Technique Internationale des Bois Tropicaux (ATIBT)

The ATIBT promotes the sustainable management of tropical forests and responsible trade in tropical timber. ATIBT has conducted studies on RIL practices, particularly in the

Congo Basin The Congo Basin () is the sedimentary basin of the Congo River. The Congo Basin is located in Central Africa, in a region known as west equatorial Africa. The Congo Basin region is sometimes known simply as the Congo. It contains some of the larg ...

, and offers practical guidelines for companies. It works with timber companies, governments, and certification bodies to improve logging methods. Through its research, training, and publications, ATIBT helps raise awareness about sustainable forest management.

References

{{Reflist Logging Forest management