Analysis of the non-native flora of Ensenada, a fast growing city in northwestern Baja California

Abstract

Urbanized areas show a high proportion of non-native plants and can work as dispersal points to the surrounding areas. Ensenada is a fast growing city located in the northwestern peninsula of Baja California (Mexico). It is the southern extreme of a binational, coastal urban corridor that extends from Los Angeles, California south to Ensenada. This corridor is part of the biodiversity hotspot of the California Floristic Province. The aim of this study was to analyze the composition and distribution of the spontaneous flora in the city of Ensenada. We systematically sampled two differentiated urban environments, vacant lots and arroyos, in 2006 and 2007. We found a total of 158 plant species, 61% of them were non-native species. Arroyo areas showed higher nonnative species richness than vacant lots (21.9 vs. 13.6 species/transect) and could be potential dispersal vectors for non-native species to natural areas outside of the city, or in the reverse direction also.

Patterns and Trends in Urban Biodiversity and Landscape Design

“…The NCEAS database contains only a few cities from Africa, Latin America and the Caribbean, and Southeast Asia and the Pacifi c Islands. The Garcillán et al ( 2009 ) study of Ensenada, Mexico provides insights into patterns of plant diversity in Central America. They report that 61 % of the vascular plant species found in arroyo (dried river beds) and vacant lot habitats are non-native species.…”

“…Ensenada has experienced rapid growth and expansion typical of cities in the global south and had a higher percentage of non-native species than reported cities in the same biogeographic realm in the United States. Garcillán et al ( 2009 ) suggest that rapid urbanization from recent population growth has resulted in a loss of remnant habitats and an associated increase in the proportion of non-native plant species. Similar changes may occur in rapidly developing cities (see Chap.…”

Studying the patterns of alien and native floras of some habitats in Srinagar city, Kashmir, India

“…Pyšek (1998) in a study, involving 54 central European cities, reported a high proportion of alien plant species which ranged between 20% and 60%. The proportion of alien species found in Ensenada, a fast-growing city located in the north-western peninsula of Baja California (Mexico) was also as high as 61% (Garcillán et al 2009). Kowarik (1990) also reported that Polish cities have an average of 50% to 70% alien plant species.…”

Distribución potencial de ocho especies exóticas de carácter invasor en el estado de Baja California, México

“…De acuerdo con Vibrans (2009), esta planta es originaria del norte de África y es bien conocida por ser una invasora de desiertos, se ha señalado que en México se comporta como una típica arvense. Garcillán et al (2009) reportaron que tiene preferencia por terrenos abandonados en la ciudad de Ensenada, Baja California. En Cal-IPC (2007), se menciona que B. tournefortii es abundante en ambas costas de Baja California; sin embargo, en el mapa de distribución potencial de esta especie su presencia no se observa en la zona costera del Golfo de California, por lo que es necesario contar con más colectas de herbario para poder tener un mejor diseño de la interpretación de la distribución potencial de esta planta, ya que sólo se encuentra en la costa del Pacífi co.…”

“…Garcillán et al (2009) registraron en zonas urbanas de la ciudad de Ensenada, B.C., 33 familias, 122 géneros y 161 especies, de las cuales 98 (61%) fueron no nativas. Mientras que Villaseñor y Espinosa-García (2004) estimaron para Baja California 219 especies exóticas.…”