Introduction
Shifting cultivation, which is also referred to as rotational bush fallow farming, slash-and-burn farming, or swidden, is an old tilling practice mostly found in tropical parts of the world. The land-use system is mainly practiced in the wet tropical highlands in South Asia, Oceania, Africa, and Latin America. Approximately 280 million hectares of land is used in this agricultural practice Nath et al., 2022). The common types of shifting cultivation encompass traditional long-rotation and short-rotation, as well as the less-studies encroaching cultivation. Practicing shifting cultivation generates debate on its threat to tropical forest. Proponents of traditional long-term shifting cultivation posit that it promotes regeneration of forest ecosystem and soil nutrients. Contrarily, those opposing believe that short rotation farming and the encroaching cultivation degrades the forest ecology and contributes to low soil fertility. While long-term rotation shifting farming considerably has little effect on soil nutrients, the paper argues that short-term rotation contributes to massive deforestation and loss of essential soil nutrients in the forest ecosystem.
Definition of Key Terms
To establish a better understanding of shifting cultivation and threats to tropical forests, it is critical to vividly identify its various types and define key concepts and terms. Based on these key definitions, a critical assessment of shifting cultivation and its impacts on the tropical forest ecosystem can be performed. The traditional long rotation shifting cultivation refers to the traditional farming method where a section of forest is cleared, vegetation burnt, land is farmed for numerous years before abandonment (Mukul et al., 2022). Thereafter, new forest land is identified and cleared for the same purpose. Secondly, Bauters et al. (2021) define short-rotation shifting cultivation as type of farming practice similar to the swidden method but has reduced fallow cycles. Encroaching cultivation refers to a phrase used to define the process of slashing and farming a plot that has never been used for agriculture. It usually happens when there is increased population growth, leading to more demand for land for subsistence goals (Li et al., 2021). It also entails situations where previously unused land is slashed for commercial farming.
Characteristics of Shifting Cultivation
Shifting cultivation has core characteristics that distinguish it from other ways of farming. Firstly, it entails using simple technique such as clearing and scorching an identified part of forest during or even before the commencement of monsoon. Forest clearing and burning is done to expose essential soil nutrients sealed in the biomass of plants to generate charred material for enriched soil fertility. The slashed locations are then plowed and farmed for many years then left fallow to permit secondary forest maturation (Nath et al., 2022). Secondly, it has fallow periods where land is abandoned to regain fertility before being used again. Thirdly, it is characterized by deforestation and soil degradation, since regular slashing and burning the vegetation results in soil nutrients depletion and degradation of forest ecology.
Shifting cultivation also has high reliance on natural resources such as forests. It is largely known for offering livelihood to about 300 million persons across the 64 countries (Nath et al., 2022). For example, about 34 million persons rely on shifting cultivation for their subsistence in Southeast Asia alone. The consistent dependence of the method of farming makes it difficult to go extinct. Many attempts to eliminate this practice have been implemented throughout the regions where it is widely practiced but it has not fully succeeded.
Threats Caused by Short Rotation and Encroaching Cultivation
Deforestation
Forest refers to land with about thirty percent canopy cover of trees of about five meters tall. Alternatively, forest cover loss on the other hand entails standard replacement due to turbulences such as shifting cultivation and other natural and anthropogenic disturbances. The United Nations Food and Agriculture Organization describes deforestation as the cautious conversation of forests to other uses through cutting of trees without replacements. However, there is a contention on the connection between deforestation and shifting cultivation.
Consistent use of short-term rotation shifting cultivation destroy the forest ecosystem through fragmentation, leading to previously undamaged areas being disrupted by edge consequences by cutting. Edge effects entail pervasive processes within tropical forests, resulting in habitat fragmentation and shifting of forest ecology coupled with greater access to interior parts of the forest. As land-use pressure rises, farmers are compelled to retreat to previously used forest sections at a quicker cycle, leading to increased interference with the rejuvenation of the fallows and the long-standing regeneration capability of the forest. Therefore, short-term rotation shifting cultivation becomes detrimental since farmers return to the land faster than expected even before the secondary tress matures (Laskar et al., 2021). The net effect is increased encroaching of new plots inside the forest to enable the accommodation of frequent clearing of the forest.
Growing population in the tropical regions and many infrastructural developments result in increased encroachment to forest land. Millions of people depend on tropical forest resources for subsistence. While a reliable approximation of the magnitude of land under swidden farming is not clear, estimates point to about 34 million individuals relying on the practice in Asia. Short fallow cycles will make lead to reduced redevelopment of secondary vegetation or even permanent loss of tress.
Loss of Soil Nutrients Composition
Soil quality is a critical component of forest attributes and is impacted by recurring swidden and other anthropogenic activities, as well as other local practices in tropical regions. Soil quality refers to the capability of the earth to accommodate trees development without additional dilapidation of the environment. Moreover, soil quality is mostly related to resilience and entails the capacity of the soil to rejuvenate its roles after significant disturbances (Bauters et al., 2021). Transformation of tropical forest lands into short-term rotation shifting cultivation possesses a wide range of effects. For example, Laskar et al. (2021) show that human activities, including short rotation shifting cultivation results in loss of soil macronutrients such as potassium, phosphorus, and nitrogen.
Other aspects such as intense burning of slashed vegetation can lead to release of essential macronutrients into the atmosphere. Moreover, clearing vegetation can also result in depreciated organic matter in the soil – the main source of nutrients (Bauters et al., 2021). For instance, the frequent utilization of the same area of forest land can cause soil depletion since the crops consume nutrients quicker than they are restocked, causing deprived crop yields.
Benefits of Traditional Long Rotation Shifting
Optimal Regeneration of Forest Ecosystem
A sustainable traditional long-rotation cultivation encompasses cyclic agricultural usage of small areas in the forest for about two seasons then abandoned for years to allow for forest ecosystem rejuvenation until soil fertility is restored. As traditionally used, this technique does not certainly lead to perpetual or enormous trees destruction since the woodland is permitted to redevelop in a natural transformation process for numerous years following clearing and farming the forest area. Sustainability of this practice depends on the revival capability of the forest to allow further agricultural productivity (Li et al., 2021). When effectively used, traditional long rotation shifting farming promotes efficient forest redevelopment and few outcomes of degradation instances. Contrary to regular cultivation seen in short rotation, which often lead to faster loss of biodiversity, long rotation fallows allow for rejuvenation of mature secondary vegetation cover to offer numerous forest ecosystem benefits.
Traditional long fallows help reduce the dangers of wildfires normally and constant burning of vegetations. Specifically, continuous land farming in short rotation agriculture causes frequent removal of vegetation cover through burning and even cutting of tress. Abandoning the land for several years makes the tress in the previously cleared area to regrow and restore the forest integrity. The phenomenon is essential as parts of efforts to curb increased forest degradation.
Longer Fallows Enhance Soil Nutrients Redevelopment
The traditional long-rotation shifting cultivation is less detrimental to forest soil quality compared to short-rotational practice. Mukul et al. (2022) illustrated that soil macronutrients such as carbon, nitrogen, and phosphorous are undisturbed and have rich contents of these elements compared to fallows that have short abandonment periods. In short rotation, this may be caused by loss of nutrients due to continual cutting of trees and frequent burning of vegetation biomass within the slashed area. In the traditional long rotations which exhibited strict controls, the forest soil macronutrients exhibited much more potassium, phosphorus, nitrogen, and carbon levels (Mukul et al., 2022). In short rotation cultivation, recurrent clearing, burning of vegetation, and run-off from the slashed areas caused excessive loss of most of the essential nutrients. Moreover, over time, most of the soil macronutrients are anticipated in the maturing vegetation, making the concentration of key mineral change due to increased plant consumption and recycling through decomposition and litterfall.
In addition, traditional long fallow farming is critical to soil nutrients restocking since it effectively participates in biodiversity conservation. For example, this practice permits a broad range of animal and plant species to flourish and create a mosaic of numerous stages of vegetation, offering habitat for many diverse species (Mukul et al., 2022). The ecosystem created as a result of increased forest recovery enhances biodiversity and improves soil quality.
Conclusion/ Discussion
The assessment establishes that shifting cultivation in tropical regions in different parts of the world still employs this land-use practice despite threats from increasing population, urbanization, and government policies. The extent and intensity of this farming method are on the decline. The research reveals considerable gaps and variability in shifting cultivation in areas of practice. Most studies have largely focused on human ecology and anthropology issues. Contrarily, research on the effects of swidden on the environment, especially tropical forests is inadequate with many scholars increasingly paying attention to this matter. The failure to distinguish the various types of shifting cultivation and their individual effects on tropical forests often leads to blanket condemnation with ramifications such as deforestation, degradation, and loss of essential nutrients. An enhanced familiarity with this matter coupled with methodical and well-articulated research, remains critical in comprehending the management and restoration capacity of tropical woodlands. Anthropogenic disturbances should also be analyzed for a profound understanding of the issue.
Traditional long-rotation shifting agriculture has been an essential land management system in the tropics for many years. Millions of small-scale farmers, especially the rural areas continue to rely on this farming practice to meet their subsistence needs. Specifically, this cultivation system differs from the short rotation shifting farming, particularly on the fallow intervals which tend to be longer hence allowing more time for better maturation of the regenerative vegetation cover. The longer the fallow cycles the better the benefits derived from swidden cultivation (Sati, 2019). The traditional long-rotation system embraces this format and reaps significant benefits from the practice.
The benefits of traditional long-rotation shifting cultivation are anchored in the regenerative capability of the forest ecosystem to sustain agricultural productivity. It is a better instance of socio-ecological resilience as both forests and human societies benefit in the long term. Moreover, increasing populations, growing developments such as road constructions, commercial agriculture, privatization of communal lands, and government policies have contributed to short fallow intervals and encroaching practices.
Traditional long rotation agriculture does not interfere with soil macronutrients such as Nitrogen, carbon, and phosphorous. The previously cleared areas remain rich of these elements compared to fallows with shorter abandonment time. Specifically, in short rotation, reduced nutrients concentration is caused by continual cutting of trees coupled with frequent burning of vegetation biomass in the identified forest area. Contrarily, the traditional long rotations exhibit strict controls with fallows spanning to several years hence making the forest soil to have higher concentration of macronutrients (Mukul et al., 2022). Therefore, it is apparent that in short rotation cultivation, issues relating to recurrent bush clearing, burning, and frequent run-off from the slashed areas caused excessive loss of most of the essential nutrients.
Moreover, the forests are generally cleared with rudimentary tools such as axe before setting fire to clean up the heaps of trees. Short rotation shifting cultivation of the forests has effects on soil property, especially the frequent cutting down of trees and the frequent utilization of fire to clean up the crop area. Soil texture is also not spared since there is loss of material and granulometric modifications with detrimental consequences of runoff coupled with the compactness of topsoil. The structure of the soil is also impacted, with effects, especially in the macro aggregates. The impacts go past those connected with the quality and influence the water holding capability, as well as the nutrient absorption ability in the soil.
The above factors, in turn, impact tropical forests’ ecosystems due to increased encroaching practices. The intensity of land use and shorter cycles causes premature cutting of successional forests hence decreasing the regenerative capacity of future vegetation. When premature cutting of trees occurs frequently, renewal is reduced and the trees do not naturally redevelop in sections earlier slashed for farming. Halted rejuvenation results in other steady situations conquered by bushes or weeds. Deprived forest redevelopment will also lead to lower farming output. Moreover, the forest soil will show reduced fertility due to the loss of essential macronutrients and the cleared areas will be prone to invasion by weeds (Bauters et al., 2021). The connection between forest ecosystem redevelopment and renewal of soil nutrients results in additional deteriorations in woodland regenerative capability.
The dichotomy of view about the demerits and merits of shifting cultivation is seen in its various land-use types. The paper recommends that shifting cultivation adheres to a traditional long rotation system and should be viewed as an effective land-use practice instead of generalizing it as the tropical deforestation perpetrator. The paper also recommends a more nuanced comprehension of the local framework and caution about the generalities of swidden farming and its connection to forest destruction and loss of soil nutrients. To enhance and implement strict conformity to traditional long rotation shifting farming, the research proposes deployment of robust governance structure and co-management including indigenous communities to help in safeguarding the tropical forests ecosystem.
References
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