Monday, April 22, 2019

Deforestation in the Brazilian State of Rodonia


1984 satellite image of Rodonia
 2016 satellite image of Rodonia 

The purpose of this research project is to map the deforestation of the Brazilian State of Rodonia caused by the history of land development in the region. The expansion of deforestation in Rodonia is mapped by using the time slider feature provided in Google Earth. By dividing the expansion of the deforestation into 10 year periods, the map easily shows how much the landscape of Rodonia has changed over the last 40 years. The history of land development and its impacts are explained primarily through the research of Dr. Marcos A. Pedlowski (1997) and Dr. Brent H. Millikan (1992), who have written extensively on this issue. This project will use their research to explain the monumental forest loss shown in the map.

Rodonia is located in the western portion of the Brazilian Amazon and contains an area of 243,044 square kilometers. In 1970, the Brazilian federal government established the National Integration Program (PIN) to protect the vast interior of the nation by relocating Brazilian citizens there. The goal of the PIN was to settle 100,000 families between 1971 and 1974. However, by 1978 only 8% of the families had been settled. This is attributed to the federal governments's failure to provide titles, lack of secure loans, and poor road maintenance.  Just as Brazil was abandoning its colonization schemes, Rodonia was undergoing a demographic boom (Millikan, 1992). The construction of the BR-364 highway started an explosive process of migration and land occupation. During the 1970s, according to the census, Rodonia's population increased from roughly 111,000 to nearly 500,000 inhabitants, an annual growth rate of 15.8% comapred with 2.5% for the entire country (Millikan, 1992). The 1990 census showed the population had increased to over 1.1 million people in Rodonia. The increased number of immigrants lured by colonization settlements combined with the construction of new roads had a strong effect on the rate of deforestation (Pedlowski, 1997).  Most migrants came without capital to provide for more sustainable agricultural practices, so they resorted to shifting cultivation methods. By 1980, more than 8000 km^2 of forest had been cleared and by 1987 it increased to 41,000 km^2.

To understand how the deforestation became so tremendous it is necessary to look at the land-use change and its impacts. In Rodonia, the main actors of land-use are small farmers, cattle ranchers, miners and loggers. In the past, the clearing of land was considered proof of land occupation by farmers, and triggered the widespread deforestation in the 1970s (Pedlowski, 1997). Typical farmers will clear small patches of natural forest to establish a mix of annual and perennial crops and pasture (Pedlowski and Dale, 1992). These patches are irregular in terms of shape, size, and spatial distribution. In addition, most farmers slash existing secondary growth to increase the area in production without having to clear more natural forest. Furthermore, farmers prefer to establish pasture in older areas and clear natural forest to establish annual and perennial crops (Pedlowski, 1997). The small farms are spatially disaggregated, thus there is a great deal of of fragmentation of the forested landscape. Because most of the farm clearings occur along roads that run in linear patterns, the deforestation has a "fishbone" pattern when viewed from above.

Cattle ranchers have less complex strategies of land clearing and use because their main interest is to plant pasture to feed their herd (Pedlowski, 1997). the pattern of cattle ranching is started by the small farmers who clear a few hectares to establish their crops. However, most farmers are forced to move when economic returns drop below critical margin. In turn, these properties are bought by a more capitalized cattle rancher. These cattle ranchers have a bigger impact on deforestation because they tend to control more areas of land to provide for their cattle. Given the low productivity of the grasses imported into the region, most ranchers tend to clear large areas of land to feed the herd continuously throughout the year (Pedlowski, 1997). Most cattle ranchers see efforts to protect the forests as a barrier to their economic viability. In addition, the inability of state agencies to enforce environmental laws is because top state officials are influenced politically by cattle ranchers. Because of this, cattle ranchers do not obey the 50% rule of the Brazilian Forestry Code, which states that farmers cannot clear more than 50% of the land they own (Pedlowski,1997). LANDSAT images show that between 80 and 95% of cleared areas of medium and large properties are occupied by pasture. The impact of cattle ranchers can be seen more clearly in ares where large properties dominate. Rolim de Moura, an area of cattle ranching, and Vale do Paraiso in central Rodonia, had only 13% and 27% of natural forests left in 1993 (Pedlowski, 1997). The number of cattle increased 263% from 1980 to 1992 with the number of cattle rising from 250,000 to over 2.7 million. The continued growth in the number of cows will certainly led to the further clearing of forests to be used as pastures. Effects of cattle ranching is more severe than small farming because of the large areas of land required to maintain pastures. Cattle ranching is the main cause of deforestation in Rodonia.

After reviewing literature, it is clear that the massive amounts of deforestation in Rodonia can be attributed to the increase in population since the 1970s, as well as small farmers and cattle ranchers. The population spike was caused by government plans to colonize the region which were very unorganized and led to migrants clearing their own land as means to establish it as their own. Small farmers also cleared natural forests to plant annual and perennial crops, as well as slashed secondary growth which led to the predominance of poor soils and a decline in crop yields. These poor farming practices were a result of farmers having no money to establish more sustainable methods. Cattle ranchers then bought these lands to develop into pasture for their cows. These large farmers are more prone to keep clearing forests as their herd needs more room to feed year round. The continued deforestation in the Amazon, especially Rodonia has led to extreme impacts of habitat loss, biodiversity loss, and climate change.







References:

FEARNSIDE, P. M. (2005), Deforestation in Brazilian Amazonia: History, Rates, and Consequences. Conservation Biology, 19: 680-688. doi:10.1111/j.1523-1739.2005.00697.x

J, Imbernon. “Population Growth and Deforestation - the Case of Rondonia in the Brazilian Amazon.” Catalog › Details for: Population Growth and Deforestation - the Case of Rondonia in the Brazilian Amazon, outputs.worldagroforestry.org/cgi-bin/koha/opac-detail.pl?biblionumber=37651. 

Millikan, Brent H. “Tropical Deforestation, Land Degradation, and Society: Lessons from Rondonia, Brazil.” Latin American Perspectives, vol. 19, no. 1, 1992, pp. 45–72. JSTOR, www.jstor.org/stable/2633551.

Pedlowski, M.A., Dale, V.H., 1992. Land-Use Practices in Ouro Preto do Oeste, RondGnia, Brazil. ORNL/TM 12062, Oak Ridge, TN. 

Marcos A. Pedlowski, Virginia H. Dale, Eraldo A.T. Matricardi, Eliomar Pereira da Silva Filho, Patterns and impacts of deforestation in Rondônia, Brazil, Landscape and Urban Planning, Volume 38, Issues 3–4, 1997, Pages 149-157, ISSN 0169-2046, https://doi.org/10.1016/S0169 2046(97)000303(http://www.sciencedirect.com/science/article/pii/S0169204697000303)

 “World of Change: Amazon Deforestation.” NASA, NASA, earthobservatory.nasa.gov/world-of-change/deforestation.php.

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