As for Africa, we found only one recent national study, on the Democratic Republic of the Congo [36]. The validation of shifting cultivation mapping is generally challenging due to the lack of reference data [41,42]. 1. Shifting agriculture | agriculture | Britannica Shifting cultivation - Wikipedia Climate change impacts on food production - The Ecologist Recent international efforts to compare and synthesize different earth system models have come with a strong focus on quantifying the past, current, and future contributions of land use to climate change [14]. Fig 1 illustrates the procedure we used for this visual inspection. Conceptualization, Shifting Cultivation: Cropping Patterns, Jhum Cycle and Problems Human influence on the land is accelerating because of rapid population growth and increasing food requirements. In addition to searching the Web of Science, we also consulted three major book publications that could be assumed to contain relevant information [2426]. The analysis presented is primarily qualitative with a supplementary quantitative analysis of the causes of forest . No, Is the Subject Area "Africa" applicable to this article? Formal analysis, India, Bangladesh), comparison of the maps (Fig 6) and the survey responses point to similar trends. This paper presents the causes and consequences of shifting cultivation and its potential land use alternatives. Effects of Deforestation The major effect of deforestation on the environment is global warming and climatic change. It is a sustainable method of farming in the rainforest. [24], who in turn had cited Dixon et al. The period of cultivation is usually terminated when the soil shows signs of exhaustion or, more commonly, when the field is overrun by weeds. After analyzing the spatially differentiated changes between the status in the 1960s to 1970s as shown in the Butler map and our data for 2010 (Fig 6), we combined them with data from our expert survey about changes in areas under shifting cultivation between 1970 to 2000 and 2000 to 2010 as well as with information from the literature. No, Is the Subject Area "Agriculture" applicable to this article? Climate change is a leading cause of deforestation. The global shift towards this model of farming in the last sixty years has come with many costs. We initiated occurrence at a one-degree resolution in 2010 (base year) at the mean of the above-stated ranges for each occurrence category in the assessment of current landscape with signs of shifting cultivation based on the GFC data (c.f. Letting it dry and burning it off. While the literature offers good representations of the major natural land covers and human land uses [68], mosaic landscapes with a dynamic mix of managed and natural land covers often fall through the cracks in global land cover and land use classifications, as these are unable to adequately capture such landscapes dynamic nature and complex spectral signatures [912]. Shifting cultivation and deforestation: A study from Indonesia The recently launched Sentinel-2 instruments with their augmented repeat frequency will generally help to improve remote sensingbased analyses of the humid tropics, which are complicated by frequent and persistent cloud cover. Our predictions of future extents of shifting cultivation are, of course, speculative. The red box marks the extent of Fig 2D and Fig 2E. The map shows large areas under such agriculture in Africa, tropical Central and South America, and Southeast Asia. For India, Goswami et al. This visualization is based on the estimation of landscapes showing signs of shifting cultivation around 2010 (Fig 5) as base year and estimated decreases of shifting cultivation (Table 3) based on the expert surveys and observed trend between the Butler map and our 2010. - Madagascar: Shifting cultivation is expected to remain widespread, especially along the eastern escarpment, until well beyond 2030. What is the Relationship Between Deforestation And Climate Change? Trends in humid tropical Africa vary widely. Shifting Cultivation: Features, Extent and Environmental Impacts Methane emissions are driving climate change. Here's how to - UNEP Please refer to the appropriate style manual or other sources if you have any questions. e. Writing original draft, Competing interests: The authors have declared that no competing interests exist. Using recent regional and national automated classification of shifting cultivation as reference (e.g. Visualization, Areas in which shifting cultivation can be assumed to have never existed or disappeared decades ago have been excluded from the analysis (dark gray). Effects | Facts - Climate Change: Vital Signs of the Planet Shifting cultivation (SC) is a traditional land-use system to ensure livelihood in the Amazon (Villa et al., 2020).The traditional SC have small areas (0.1-0.8 ha) and short cycles of agriculture (1-3 years) with high crop diversity followed by fallow periods of 2-7 years [Fig. The climate of most European countries is wet First, we compared the Butler [13] map (Fig 4) with our own spatial estimate (Fig 5) of areas that were under shifting cultivation around 2010. One land-clearing system of shifting agriculture is the slash-and-burn method, which leaves only stumps and large trees in the field after the standing vegetation has been cut down and burned, its ashes enriching the soil. It is a system of rotating cultivation on a plot of land for 2-3 years and leaves it fallow for another 10-15 years. What is shifting cultivation? What are its disadvantages? - Toppr e0184479. They write new content and verify and edit content received from contributors. (Fig 2DA) and (Fig 2E): The white line grid marks the 1/100 degree cells used as basic unit for the validation data. Of the remaining 225 authors, 72 responded and 49 provided usable information (see S1 File). The ashes are then mixed with the soil. This indicates that, despite the subjectivity involved on estimating the landscape level of occurrence of shifting cultivation in our classification, the method led to reproducible and accurate results. No, Is the Subject Area "Earth systems" applicable to this article? It does so by following natural cycles, recycling nutrients and water, while omitting excessive use of agricultural chemicals. It received 1 point in For Southeast Asia, Schmidt-Vogt et al. [24]). Slash-and-burn agriculture is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden.The method begins by cutting down the trees and woody plants in an area. Yes What Is Intensive Agriculture? - Sentient Media After being used to grow a variety of crops for a year or two, the area is allowed to lie fallow for a period of rejuvenation, while the farmer moves on to a . The five classes corresponded to the following rough ranges of area shares of shifting cultivation landscapes (currently cultivated fields plus all stages of fallows) within an entire one-degree cell: none: < 1%; very low: 19%; low: 1019%; moderate: 2039%; high: 40%. Conceptualization, Extreme precipitation events can disturb plant growth, particularly in recently burned forests, and make plants more vulnerable to flooding and soils to erosion. At present, net area sown in Mizoram State is only 5.5%, of which, 16.9% area is devoted to shifting cultivation. Department of Geographical Sciences, University of Maryland, College Park, United States of America, Roles Discover a faster, simpler path to publishing in a high-quality journal. In order to assess both past and future land use transitions in areas currently under shifting cultivation, we identified experts with recent knowledge of these areas by searching the Web of Science (All Databases) for papers published between 2005 and 2015 whose title contained shifting cultivation or similar terms. Citation: Heinimann A, Mertz O, Frolking S, Egelund Christensen A, Hurni K, Sedano F, et al. The difference appears plausible if we consider that Spencers estimate is based on a hand-drawn map and that Asia has seen considerable decreases in shifting cultivation since that map was created (see section on recent trends below). At the regional scale, the only number to which we can compare our result is the 110 Mha for Asia estimated by Spencer [45], which is considerably larger than our estimate for this region of approximately 70 Mha. Large forest or vegetation areas are cleared and burned down for mining operations. Methodology, Southwest. Logging This has led to a paucity of global information on certain land use systems, including shifting cultivation at the global level. Comparison of these figures with the GLC2000-based area estimate for Laos of almost 11 Mha [1] underlines the problem of using the GLC2000 to estimate areas under shifting cultivation. As the data we used (GFC as well as Bing and Google imagery) cover the period from 2000 to 2014 and 2015, respectively, our assessment of the current extent of shifting cultivation does not relate to any specific year. Maps created in QGIS 2.16. https://doi.org/10.1371/journal.pone.0184479.g001. We did not perform any detailed spatial delineation of the actual area under shifting cultivation, as the goal of our study was to provide a global one degreegridded product. Simran IAS Academy on Instagram: "#Learnbymaps is here to explain you It ensures the forest will recover. Furthermore, it should be noted that the large difference between the two spatial data sets (Fig 6) in arid and semiarid parts of Africa (Sahelian and Sudanian zones of northern Africa as well as parts of southern Africa) is partly due to the fact that Butler included other, non-shifting smallholder farming systems in his map. Shifting cultivation, which is still prevalent in the uplands of eastern Bangladesh, contributes significantly to forest loss and is the main cause of land degradation. of Energy, grant number DE-SC0012972, and the Global Land Project Grant from the University of Copenhagen. Data curation, asked to explain two reasons why shifting cultivation is expected to decline in the future. The map shows that shifting cultivation is still present across large areas of the humid tropics. About half of tropical deforestation is commonly explained by the expansion of traditional agriculture (shifting cultivation). Researchers are currently developing automated approaches that are capable of processing decades of Landsat data and detecting the spatio-temporal patterns of shifting cultivation. To generate a spatially explicit prediction of the temporal dynamics (decline) of shifting cultivation through to the 2090s, we combined the survey results with several simple assumptions. However, it is important to underline that this assessment is based on very few survey responses (Fig 3) due to the small number of existing studies on shifting cultivation in Africa. The colored pixels indicate clearings in different years between 2000 and 2014 as recorded in the GFC data set [8]. Revitalizing the practice of shifting cultivation: A - IFAD As global level ground data collection is not feasible and no global data on shifting cultivation for the considered time span of 2000 to 2014 is available, we generated a validation dataset, which contains a detailed delineation of the areas under shifting cultivation for a stratified sample of one-degree cells. northern Zambia and in the Democratic Republic of the Congo), parts of southeastern Africa (e.g. Funding: This research was supported by the Institute of Geography and the Centre for Development and Environment (CDE), University of Bern, Switzerland, as well as the Swiss Programme for Research on Global Issues for Development (r4d) supported by the Swiss National Science Foundation (SNSF) and the Swiss Agency for Development and Cooperation (SDC), grant number 400440 152167, the U.S. Dept. The selection process ensured that all are experts in the field, but there may be disciplinary or personal differences in the way that especially the future of shifting cultivation was assessed. Despite the limited number of survey responses on Central and South America, it appears that here, unlike in Southeast Asia, areas under shifting cultivation have not seen a strong decline over the last 20 years. Cultivation of the earth after clearing is usually accomplished by hoe or digging stick and not by plow. [55], citing the Wasteland Atlas [56], estimated the extent of shifting cultivation in the mid-2000s at 5.6 Mha (only area under cultivation), whereas the GLC2000-based estimate is 7.6 Mha [1]. 2.2). Shifting agriculture has frequently been attacked in principle because it degrades the fertility of forestlands of tropical regions. Lastly, it is also problematic that shifting cultivation has been subject to recycling of statements about its importance that have no basis in thorough empirical research. Climate change has caused increased heat, drought, and insect outbreaks. Environmental Impacts of Agricultural Modifications Myanmar [6365]), Central America (e.g. Monoculture Farming Explained: What Are The Pros And Cons? The respondents were asked to estimate the current spatial extent of shifting cultivation as well as past and future trends in the development of this extent in their area of interest. 10 Sustainable Farming Methods and Practices | Greentumble Shifting cultivation is an agricultural system in which plots of land are cultivated temporarily, then abandoned while post-disturbance fallow vegetation is allowed to freely grow while the cultivator moves on to another plot. By zooming into areas where these clearings indicate possible shifting cultivation, we were able to determine visually whether they were accompanied by the pattern of fallows characteristic of shifting cultivation (Fig 1E) or not (Fig 1D). here. Regarding South and Southeast Asia, a meta-analysis by van Vliet et al. It is important to note that these are indeed very rough possible scenarios and should be seen as expected trends rather than fixed percentages of decline. For example, many of the commercial or smallholder oil palm and rubber plantations that cover large areas of Southeast Asia today are on land that was formerly used for shifting cultivation [1821]. The ranges are based on the expert survey and observed trends between the Butler map and our 2010 classification (Fig 5). 5 Causes of Deforestation | One Tree Planted An online questionnaire was designed and sent to these 270 authors in September 2015 using survey monkey. However, we found that its occurrence in most one-degree cells, where it existed, was fairly limited, with roughly 85% of these cells showing occurrence levels below 20% (currently cultivated fields and all stages of fallows). Formal analysis, In some specific areas, especially in Central Africa, it is likely to increase over the next decade before it begins to decline. Supervision, Plants, Animals, and Ecosystems. The search was performed in January 2016 and generated 324 articles, which we then screened for data on numbers or estimates of global or national areas influenced by shifting cultivation. c. Agriculture is the main stay of India's economy. We estimate the current global extent of shifting cultivation and compare it to other current global mapping endeavors as well as results of literature searches. [3037]) such approaches cannot yet be up-scaled to global level due to data availability as well as computational limitations. PLoS ONE 12(9): For example, the large areas of tree plantations established in Vietnam and southern China in the 1980s and 1990s can also leave a mosaic signature at a certain point in time and might therefore be incorrectly interpreted as shifting cultivation (Fig 1). Areas drenched by irrigation can become waterlogged, creating soil conditions that poison plant roots through anaerobic decomposition. Applying these largely survey-based estimates (Table 3) to our map of the extent of shifting cultivation in 2010 (Fig 5), we were able to visually display our rough predictions of developments in the extents of shifting cultivation by 2030, 2060, and 2090 (Fig 7). Peninsular Malaysia, central and southern Thailand) [28]. Surprisingly, our estimate is not too far from the 259 Mha proposed in Silva et al [1], even though their estimate excludes large areas under shifting cultivation and includes areas under other forms of agriculture and natural vegetation. [68]). Cultivation (tillage) is a practice that has been introduced to Australia from Europe by our farming pioneers. Cultivation (the preparation of land for planting crops) on the plot is done for a few years until the fertility of the formerly burned land is reduced. Data Availability: All relevant data are within the paper and its Supporting Information files. Many of the other decreases from Butlers to our map (dark brown in Fig 6) can also most likely be related to the actual disappearance of shifting cultivation in these areas that have seen significant land use transitions over the past 40 to 50 years. In addition, to the extent multi-temporal very high resolution imagery was available on Google Earth, these were used to get an even better impression of the landscape and its land-use dynamics. The global food system is in crisis. Intensive agriculture has dominated the global food production . The effects on seasons of a changing climate are already being seen across the country and vary region to region: temperatures have risen across seasons, growing seasons have become longer, precipitation patterns have changed, and extreme precipitation events have increased in frequency and severity. [52]; the latter source, however, does not provide this information, so the 1,000 Mha claim seems to be unfounded. Based on this we expect that shifting cultivation is likely to decrease significantly in all regions over the next 20 years, and we estimate that it will tend towards disappearance in all regions by 2090 (Table 3). Visualization, Shifting cultivation tends to persist when population density is low and when options for agricultural development or alternative livelihoods are limited [22,70,71]. For this reason, the known widespread decrease in the occurrence of shifting cultivation in Southeast Asia (e.g. There is a need to transform shifting cultivation to sustainable intensification. For large parts of insular Southeast Asia and South Asia (e.g. Shifting Cultivation | Advantages & Disadvantages | PDF - Study Today Using the mean values of the ranges specified for the different occurrence classes for all cells in all classes results in a total area of 280 Mha. This number certainly requires further validation before it can be claimed to be an adequate estimate of the global area under shifting cultivation. We have nonetheless ventured to display our estimates in predictive maps because they are based on a spatially explicit analysis in 2010. Agriculture CBSE Class 10 SST Geography Extra Questions Forest and trees play an important role in balancing the environment. In Asia, we expect that continued rapid economic development and the related changes in agricultural practices and, more importantly, in the economic structure (from the primary to the secondary and tertiary sectors) may cause shifting cultivation to disappear faster than in Africa or the Americas. Methodology, In shifting cultivation method of agriculture an area of land is cleared off its vegetation and cultivated for a period of time and then abandoned. Writing original draft, Roles 2030, 2060, 2090) shifting cultivation was expected to disappear completely from a specific country (n = 21), all one-degree cells having their centroid within that country where classified as having zero occurrence of shifting cultivation after that time, regardless of the above-described gradual decrease. Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. Solution: a. India is an agricultural country. Our main objectives in this study are therefore 1) to review published knowledge about current status and past trends in the development of the global extent of shifting cultivation; 2) to assess the recent global distribution of shifting cultivation and, based on these trends and expert statements, 3) to provide a first estimation of the future extent and spatial distribution of shifting cultivation until 2090. By contrast, we expect that shifting cultivation will persist for a longer time in Africa, especially in Central Africa. Population growth, economic development and urban migration have stimulated unprecedented demand for animal protein and with the global population approaching 10 billion, this hunger is expected to increase by up to 70 per cent by 2050 . We used a search string similar to the one used for the literature review: [Title]: "Shifting cultivation" or swidden or "slash-and-burn" or "slash and burn" or "shifting agriculture" AND [Year published]: 20052015. - West Africa (Sierra Leone, Liberia, Guinea, Cte dIvoire, Ghana): Shifting cultivation is anticipated to diminish rapidly by 2030 and to largely disappear by 2060 if peace is upheld and there is no major return of Ebola; but if conflicts resurface, shifting cultivation may persist well into the second half of this century. Methodology, Shifting Cultivation at a Crossroads: Drivers and Outcomes of Recent Articles with data at subnational scales were only considered if the subnational area studied constituted the main area of shifting cultivation in the given country (and thus a reasonable estimate of the national extent of shifting cultivation).
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