Sierra Norte de Puebla - Geography

Geography

The region consists of sixty eight municipalities, most of which are considered rural, located at the far north of the state of Puebla, north and east of where the state of Tlaxcala cuts into Puebla. Most of the Sierra Norte corresponds with the Puebla subregion of the Carso Huasteco, which covers an area of 448,927 hectares or thirteen percent of the state.

The area is at the intersection of the Sierra Madre Oriental and the Trans-Mexican Volcanic Belt. These mountains extend eastward into the state of Veracruz until the narrow Gulf of Mexico coastal plain. The areas rocks is mostly sedimentary with some volcanic, but all have been altered by tectonic processes caused by the moving earth and forming the mountains here. The area is very rugged with few narrow valleys with about 60% of the territory made up of steep slopes. Altitudes range from 100 to 2,300 meters above sea level. The area is filled with caves and caverns, many of which are little explored. The area’s mountains are divided into the Sierra de Zacapoaxtla, Sierra de Huauchinango, Sierra Teziutlán, Sierra de Tetela de Ocampo, Sierra de Chignahuapan and Sierra de Zacatlán. The highest altitudes are over 4,200 meters above sea level. Main elevations include Apulco, Chichat, Chignahuapan, Soltepec and Tlatlauquitepec.

The Sierra Norte de Puebla is susceptible to landslides due to its many steep inclines and heavy rain. The town of Pahuatlán is over an ancient landslide. The relative prosperity of the 20th century has spurred development of large towns with cement block structure, significantly heavier than traditional homes. This has made a number of areas, such as Pahuatlán, more vulnerable to landslides as they are located on mountainsides. Deforestation and road construction have also increased the risk. Major landslides have occurred in 1955, 1989, 1995, 1999, 2001, 2005, and 2007. The last was due to two hurricanes (Dean and Lorenzo) and isolated a number of communities for days.

The Sierra Norte is the rainiest part of Puebla with average rainfall in most places between 1500 and 3,000mm, with Cuetzalan having the highest precipitation zone at between 4,000 and 6,000mm. Most of the surface water is in fast moving streams and small rivers, some of which run only in the rainy season and many of which can be torrential when rains are heavy. The three most important rivers are the Necaxa and Apulco. Other important rivers include the Pantepec, Laxaxalpan, San Pedro (Zun), Zempoala, Cedro Viego, Salteros and Martínez de la Torre. All of these flow towards the Gulf of Mexico, in the drainage basins of the Nautla, Tecolutla, Cazones and Tuxpan Rivers . As it is one of the rainiest areas of Mexico, the water flow here is high, measuring about 6,697mm2, accounting for sixty percent of new runoff for Puebla with about 2/3 flowing into Veracruz. The main aquifer is the Tecolutla, which has 70% of the underground fresh water in the area, followed by the Libres-Oriental, Martínez de la Torre-Nautla and Perote-Zayaleta.

The region has great biological diversity because of the wide variance in altitude. Wild vegetation can be classed as perennial tropical forest, mountain mesophyll forest, pine-holm oak forest, pine forest with large areas of transition from one to another.(mamartinez) The ecosystem of the region is highly disturbed with urban areas along with farms, areas of secondary vegetation as well as areas with primary vegetation.

The Sierra Norte is divided into four subregions, according to its ecology and agriculture. The area nearest the highlands of Puebla and Tlaxcala in the south is called the Bocasierra. This strip of land has elevations of between 1,500 and 2,500 meters above sea level, with a primarily temperate and cold climate. Main crops are apples, plums, pears, peaches, avocados and certain flowers and ornamental plants. It is economically and politically the most important area of the Sierra Norte and includes municipalities such as Huauchinango, Zacatlán, Chignahuapan, Tetela de Ocampo, Zacapoaxtla, Zaragoza and Teziutlán. The coffee growing region has elevations between 200 and 1,500 meters above sea levels with a very humid, temperate-warm climate, which is optimal for coffee and black pepper. This area includes the municipalities of Cuetzalan, Tuzamapan, Huehuetla, Xochitlán de Vicente Suárez, Zapotitlán de Méndez, Hueytlalpan, Ahuacatlán, Aquixtla, Zihuateutla, Pahuatlán and Naupan. The Zona Baja (low area) includes areas below 200 meters above sea level. It has a tropical climate with agriculture dedicated primarily to citrus fruits such as oranges, mandarin oranges, grapefruit, papaya and mamey. It is also noted for its cattle. It includes the municipalities of Francisco Z. Mena, Venustiano Carranza, Pantepec, Jalpan and Tenampulco. The Declive Austral (southern slope) de la Sierra is an arid area as the winds from the Gulf of Mexico that brings in moisture do not get this far as often. This area has large haciendas which use high technology irrigation systems for crops such as barley and wheat. It is also noted for the raising of horses. It includes the municipalities of Ixtacamaxtitlán, Cuyoaco, Tepeyahualco, Libres and Ocotepec .

While much of the agriculture and other economic activities are adapted to the various ecologies of the region; however, overexploitation has severely damaged many of these systems and in turn, the economic support of many indigenous communities. Much of the original forest has been cut for pasture and for cultivation as well as for wood. Deforestation has led to greater danger from landslides.