in the Amazon and parts of the Democratic Republic of the Congo), or a residual form of cultivation in landscapes that have mostly been transformed to other land uses (such as permanent agriculture or tree crops, e.g. Data Availability: All relevant data are within the paper and its Supporting Information files. The number of estimates of areas under shifting cultivation at regional and national scales in the literature is also very limited. 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. According to Olofsson et al. [43] when using the same source material for the classification as for the reference or validation data, it is essential to create the reference/validation data with a more accurate process than the classification. Shifting cultivation in general, is a system of farming in which fields are prepared by cutting down the natural vegetations. This paper presents the causes and consequences of shifting cultivation and its potential land use alternatives. It coincided with the end of the last ice age and the beginning of the. Yet most of the common farming techniques employed in . 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. We limited the search to the period from 2005 to 2016 partly because we were interested in the most recent data on the extent of shifting cultivation as a basis for generating a map showing the contemporary situation (around the year 2010); the other reason was that we expected many recent reports on areas under shifting cultivation to rely on previously published data, which would enable targeted backtracking through the literature all the way to the original sources. 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. asked to explain two reasons why shifting cultivation is expected to decline in the future. This has led to a paucity of global information on certain land use systems, including shifting cultivation at the global level. The accuracy levels of our classification were high with an overall accuracy above 87%. Also when considering the different levels of occurrence of shifting cultivation estimated based on the overall impression of the landscape per one-degree cell, the accuracies were high (see confusion matrix in Table 2), with an overall classification accuracy of 87.8%. IWGIA - IWGIA - International Work Group for Indigenous Affairs Formal analysis, From this, we excluded regions where shifting cultivation can safely be assumed to not have been present for centuries (e.g. Please refer to the appropriate style manual or other sources if you have any questions. From droughts and wildfires to pests and pathogens, climate change is wreaking havoc on the world's forests. Validation, This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 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. An online questionnaire was designed and sent to these 270 authors in September 2015 using survey monkey. 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. PLOS ONE promises fair, rigorous peer review, The climate of most European countries is wet Traditional Agriculture and its impact on the environment - Jagranjosh.com Panama, Guatemala) well into the 2000s. How Climate Change Will Affect Plants - State of the Planet Department of Geographical Sciences, University of Maryland, College Park, United States of America, Roles Shifting cultivation decreases the activities of useful microorganisms found in the soil. 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. Click through the PLOS taxonomy to find articles in your field. To stress the interactions between society and the environment, the driving forces (D), pressures (P), states (S), impacts (I), and response (R) (DPSIR) framework approach . [24]). The analysis presented is primarily qualitative with a supplementary quantitative analysis of the causes of forest . Improvements in mapping the extent of shifting cultivation and trends in its development may be expected in the near future. 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. [17], contrasts with developments in other parts of Africa, where decreases and the disappearance of areas under shifting cultivation have dominated over the last two decades. decadal), the areas newly classified as having shifting cultivation (blue in Fig 6) should be added to the original Butler map, thereby producing an updated estimated extent of shifting cultivation for this earlier period. b. Bing and Google Earth) were used. Shifting cultivation and deforestation: A study from Indonesia Soil is the foundation of most types of agriculture. No, PLOS is a nonprofit 501(c)(3) corporation, #C2354500, based in San Francisco, California, US, Corrections, Expressions of Concern, and Retractions, https://doi.org/10.1371/journal.pone.0184479, ftp://ftp.fao.org/docrep/fao/003/y1860e/y1860e00.pdf, https://www.cia.gov/library/publications/the-world-factbook/geos/cg.html. [17] showed that these regions have experienced marked decreases in shifting cultivation. Plants, Animals, and Ecosystems. Writing review & editing, Affiliation Fig 1A shows a one-degree square of northern Laos. The evil effects of shifting cultivation are devastating and far reaching in degrading the environment and ecology of this region. [3037]) would be insufficient, as they only cover very few of our one-degree cells and are not representative globally. The main outcomes presented in this study are maps showing the estimated presence of shifting cultivation at a one-degree resolution for the present, as well as, for the first time, estimations for 2030, 2060, and 2090. [1]. We have nonetheless ventured to display our estimates in predictive maps because they are based on a spatially explicit analysis in 2010. broad scope, and wide readership a perfect fit for your research every time. [24], who in turn had cited Dixon et al. Our point of departure is a global map of the distribution of primitive subsistence agriculture produced by Butler in 1980 [13], a visual inspection of the distribution of shifting cultivation based on the 20002014 Global Forest Change (GFC) data set [8] and very highresolution satellite imagery, as well as an expert survey. 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. The global food system is in crisis. Reducing intensification by shifting cultivation through sustainable A study conducted by the Food and Agriculture Organization (FAO) of the United Nations in 1985 (based on 90 tropical countries reporting forest fallow areas within the FAO/UNEP Tropical Forest Resources Assessment Project 1982 [49]) estimated the worldwide extent of shifting cultivation in the early 1980s at 400 Mha [50], and an assessment made in 2011 with the aim of estimating greenhouse gas emissions arrived at 260 Mha for the 2000s [1]. 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. According to our tentative predictions, shifting cultivationwhich has been a globally important form of human crop cultivation for millenniamay be gone by the end of this century. Shifting Cultivation Shifting Cultivation Agricultural Geography Agricultural Hearths Agricultural Production Regions Agricultural Revolutions Agriculture and Climate Agriculture and Pollution Agrochemicals Community Supported Agriculture Extensive Farming Feeding the World Food Desert Food Insecurity Food Movements Green Revolution 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). Silva et al. Causes and consequences of shifting cultivation and its alternative in Yes But information about such landscapes is urgently needed to improve the . The excessive growth (or bloom) of algae and plankton in a water body are indicators of this process. The area approximation of actual shifting cultivation landscapes was performed based on the average occurrence rates in the one-degree cells for each of the five classes above (>1% class: 0%; 19%: 5%; 1019%: 15%; 2039%: 30%; 40%:70%). Generally, the two approximations of areas under shifting cultivation are in fairly good agreement, especially when considering that the large differences in the arid areas of northern Africa, southern Angola, and Zambia and the high-mountain areas of eastern Bolivia are largely explained by the fact that Butler included other, non-shifting forms of extensive smallholder agriculture and that shifting cultivation in these areas based on the climatic condition never could have been widespread. While keeping in mind the inherent limitations of these predictions, we can identify a number of more specific patterns. Impact of shifting cultivation on environment: an assessment on the Mexico and Brazil) likely to see a fairly rapid decrease and disappearance. The earlier 15-20 years cycle of shifting cultivation on a particular land has reduced to two or three years now. 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. These approaches, however, are still in the making and will require substantial resources. The map shows that shifting cultivation is still present across large areas of the humid tropics. Why poison ivy is an unlikely climate change winner. https://doi.org/10.1371/journal.pone.0184479.t001. Since there have been many controversies about the impact of jhum cultivation the study was done to analyse the current situation of the practice of shifting cultivation as perceived by the local people of Mokokchung village. Given that biomass regrows very quickly in the humid tropics, the GFC data set treats large shares of a field cleared for shifting cultivation and kept fallow for a relatively short period as deforestation. If the survey provided information about when (i.e. For each grid cell, the occurrence of shifting cultivation declined linearly by the mid-point of the estimated losses in 2030, 2060 and 2090 (see Section 3.4). - 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. 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. Conceptualization, Let us know if you have suggestions to improve this article (requires login). 1. 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. Cultivation of the earth after clearing is usually accomplished by hoe or digging stick and not by plow. We would like to emphasize that the maps in Fig 7 are indeed very coarse estimates of the future global or continental extent of shifting cultivationand not an exact representation of where precisely it might be found in the near or far future. of Energy, grant number DE-SC0012972, and the Global Land Project Grant from the University of Copenhagen. [2] included shifting cultivation in a global harmonization of land use states and transitions from past to future: they found only one (hand-drawn) global map of shifting cultivation, in a book on economic geography dating from 1980 [13]. Road Building The Transamazon Highway has allowed increased access to the Amazon Rainforest. 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. It ensures the forest will recover. within global land-use models) needs spatially explicit estimates of areas under shifting cultivation at intervals lying between the status shown in the Butler map (1960s to 1970s) and our estimations for 2010 (e.g.
