Ji-Paraná River: A Vital Waterway of the Brazilian Amazon
The Ji-Paraná River, also known as the Machado River, is a significant waterway located in the state of Rondônia in western Brazil. As a key tributary of the Madeira River, it plays a crucial role in the vast Amazon Basin, contributing to the complex network of water that eventually flows into the Atlantic Ocean.
For a large portion of its course, the river runs roughly parallel to the northeastern border of Rondônia. It is most notably recognized for dividing the city of Ji-Paraná, where the BR-364 highway crosses the water via a major bridge.
[ไม่มีภาพประกอบ]Key Facts
- Total Length: 820 kilometers (510 miles).
- Basin Size: 76,127 square kilometers (29,393 square miles).
- Primary Mouth: Flows into the Madeira River.
- Average Discharge: 2,100 cubic meters per second.
- Conservation: Supports three major protected areas including the Jaru Biological Reserve.
Geography and Physical Characteristics
The Ji-Paraná begins at the confluence of the Pimenta Bueno and Comemoração rivers on the Parecis plateau, starting at an elevation of 173 meters (568 feet). From there, it travels through the landscape of Rondônia until it reaches its mouth at the Madeira River, where the elevation drops to 43 meters (141 feet).
Hydrology and Flow
The river's discharge—the volume of water moving through the channel—varies significantly. While the average discharge is 2,100 m³/s, it can drop to a minimum of 596 m³/s and surge to a maximum of 4,360 m³/s during peak periods.
Tributaries
The river is fed by numerous tributaries that expand its reach across the basin:
- Left-bank tributaries: Pimenta Bueno, Jaru, Rolim de Moura, Muqui, Urupá, Machadinho, Juruazinho, and Preto.
- Right-bank tributaries: Comemoração and São João.
Environmental Conservation and Biodiversity
The Ji-Paraná basin is home to several critical conservation units designed to protect the region's unique biodiversity and manage sustainable land use.
The Jacundá National Forest covers 221,218 hectares (546,640 acres) and is designated as a sustainable use conservation unit. In contrast, the Jaru Biological Reserve, established in 1984, is a fully protected area spanning 346,861 hectares (857,110 acres).
Additionally, the river serves as the southern boundary in Rondônia for the Campos Amazônicos National Park. Created in 2006 and covering 961,318 hectares (2,375,470 acres), this park is scientifically notable for containing an enclave of cerrado vegetation—a tropical savanna ecosystem—situated within the broader Amazon rainforest.
| Feature | Detail |
|---|---|
| Alternative Name | Machado River |
| Country | Brazil (Rondônia) |
| Length | 820 km |
| Basin Area | 76,127 km² |
| Source Elevation | 173 m |
| Mouth Elevation | 43 m |
| Progression | Madeira → Amazon → Atlantic Ocean |
Frequently Asked Questions
What is the other name for the Ji-Paraná River?
The Ji-Paraná River is also known as the Machado River.
Which larger river system does the Ji-Paraná belong to?
It is a tributary of the Madeira River, which is part of the larger Amazon River system flowing into the Atlantic Ocean.
What makes the Campos Amazônicos National Park unique?
The park is unusual because it contains an enclave of cerrado vegetation (savanna) located within the Amazon rainforest.
What are the conservation areas located within the river's basin?
The basin includes the Jacundá National Forest, the Jaru Biological Reserve, and the Campos Amazônicos National Park.
Where is the river's source located?
The river begins at the confluence of the Pimenta Bueno and Comemoração rivers on the Parecis plateau in Rondônia, Brazil.