HYDROLOGIC BALANCE OF LAKE CHAPALA (MEXICO)¹

Abstract

Lake Chapala, whose primary tributary is the Río Lerma, is the largest freshwater lake in Mexico and for the past 95 years has maintained an average storage capacity close to 6,700 Mm3. Starting hi the early 1970s, the Lerma‐Chapala basin rapidly industrialized. In response to these upstream anthropogenic activities, the fisheries, aesthetics, and water quality of Lake Chapala have decreased as a consequence of the increasing chemical and biologic pollutants mainly from the Río Lerma. Additionally, the growth of Guadalajara has resulted in increasing potable water demands on the lake to satisfy a population currently greater than 4.5 million. During the 1980s, the outflow and water losses from the lake substantially exceeded the inflow and other water contributions. In this paper, the recent behavior of the hydrologic and bathymetric parameters of Lake Chapala are summarized and some important physical stresses on the system are identified. The focus of this work is the 1934–1989 period, and it is shown that starting around 1980 some of the main contributors to the lake water balance were severely perturbed and the lake reached its second lowest recorded level. The disturbances of the system are so severe that the entire regional ecosystem could be irreversibly affected in the near future.

Radiocarbon age inversions and progression: source and causes in Late Holocene sediments from Lake Chapala, western Mexico

“…1a). The watershed (*54,000 km 2 ) comprises the Lerma River (*500 km) and Lake Chapala, the largest freshwater lake in Mexico and the third largest lake in Latin America (de Anda et al 1998). The lithology of the Lerma-Chapala watershed has been described elsewhere (Ferrari et al 1997(Ferrari et al , 2000Zárate-del-Valle et al 2002).…”

Computation of changes in the run‐off regimen of the Lake Santa Ana watershed (Zacatecas, Mexico)

“…The input and output components of the water balance of a lake or reservoir depend on its bathymetric features, the climate, and hydrological, geological and anthropogenic factors (de Anda et al . 1998).…”

“…2002). Hydrologists have addressed this problem by quantifying the behaviour of the different processes of the hydrological cycle over a long time period, thereby making it possible to simulate these processes at the watershed level (de Anda et al . 1998; Winter & Springer 2003; Ortiz‐Jiménez et al .…”

Quantifying uncertainty and confusion in land change analyses: a case study from central Mexico using MODIS data

“…The heterogeneity, variability, and rate of land change in the LCS watershed and across Mexico have been observed and demonstrated through multiple sources and methods (de Anda et al 1998;Alvarez et al 2003;Cotler, Mazari Hiriart, and de Anda Sanchez 2006). Yet, the classification of this landscape and the quantitative assessment of discrete land cover change has proven challenging.…”

“…(Figure 1). Across its 700 km breadth, the LCS spans more than 4000 m in elevation, from the western ridge of the Valley of Mexico to the Pacific Coast, encompassing the drainages of the Lerma River (Río Lerma) (45% of watershed), Lake Chapala, and the Santiago River (Río Grande de Santiago) (55% of watershed), totaling nearly 136,000 km 2 (de Anda et al 1998). With diverse geomorphology, the region includes mountain pine-oak forests, mid-elevation shrubby grasslands, and coastal inundated agricultural zones, among other land cover types…”