Macrophytes assemblages in mountain lakes of Huerquehue National Park (39ºS, Araucania Region, Chile)

Abstract

ABSTRACT. The lakes studied (Tinquilco, Verde, Toro, Chico) are located in the Huerquehue National Park (39°08'S, 71°40'W), Chile. An inventory of the aquatic and riparian species was performed between December 2005 and March 2006. A null model analysis was done to determine the existence of regulatory factors of species associations, and the Jaccard index was applied to determine floristic similarities. Seventyfive species were identified. The greatest number (54) and highest percentage of introduced species (37%) occurred at Tinquilco Lake, placing it in the category of "high human disturbance". Verde Lake, on the other hand, presented the lowest number of species (21), and the percentage of introduced species did not exceed 20% in the other three lakes, which are considered to have "low human disturbance". The analysis of the null model revealed the presence of regulatory factors in one of the three simulations. However, in the other two simulations, the species associations appeared to be random, presumably because many species were repeated at the study sites. According to the Jaccard index, Tinquilco Lake is noticeably different from the other lakes, probably due to its transition from oligotrophy to mesotrophy. Keywords: oligotrophy, mesotrophy, macrophytes, null model, lakes, Patagonia, Chile. Ensambles de macrófitas en lagos de montaña del Parque Nacional Huerquehue(39°S, Región de la Araucanía, Chile) RESUMEN. Los lagos estudiados (Tinquilco, Verde, Toro, Chico) se localizan en el Parque Nacional Huerquehue (39°08'S, 71°40'W). Entre diciembre de 2005 y marzo de 2006, se inventarió su flora acuática y ribereña. Para determinar la influencia de factores reguladores en las asociaciones de especies se aplicó un análisis de modelo nulo y para determinar similitudes florísticas se aplicó el índice de Jaccard. Se identificaron 75 especies, donde el mayor número (54) y el mayor porcentaje de especies introducidas (37%) se registró en el lago Tinquilco, por lo que se incluye en la categoría de "altamente intervenido"; mientras que el menor número de especies se registró en el lago Verde con 21, y el porcentaje de especies introducidas no superó el 20% en los otros tres lagos, por lo cual se consideran como "poco intervenidos". Los análisis del modelo nulo muestran la presencia de factores reguladores en una de las tres simulaciones, mientras que en las dos restantes se sugiere una asociación aleatoria de las especies, supuestamente explicada por la presencia repetida en los sitios. El índice Jaccard reveló que el Tinquilco es notablemente diferente a los otros lagos, cuya probable causa se relacionaría con la transición de oligotrofía a mesotrofía.

Macrophytes assemblages in mountain lakes of Alerce Andino National Park (41° S, Lakes Region, Chile).

“…2). The relatively low percentage of non-native species indicates a certain anthropized degree on their banks (Hauenstein et al, 1988(Hauenstein et al, , 2011, which would below, according to the scale of González (2000), to the category of "low human disturbance" for the three lakes of higher altitude (Chaiquenes, Triángulo, Sargazo), with one introduced species, these lakes have access difficults and it is probably that the presence of one introduced species would be to accidental introductions due tourism activities; instead the Chapo Lake has a high introduced species that would be associated to human intervention due rural communities and salmoniculture activities, that has classified it in the category of "high human disturbance".…”

“…Nevertheless, an oligotrophy to mesotrophy transition has been observed in some lakes located mainly between 38 to 41°S, due to the replacing of the native forest of their basin by agricultural zones, towns and industries (Soto, 2002;Villalobos et al, 2003;Woelfl et al, 2003;Woelfl, 2007). One of the biotic components that can be an indicator of trophic status is the assemblage of macrophytes (Hauenstein et al, 2002(Hauenstein et al, , 2011Nagasaka, 2004;Li et al, 2009). We define macrophytes according to Ramírez & Stegmeier (1982).…”

Spectral Properties Observations: a First Comparison of Bulgarian and Chilean Mountain Lakes

“…Oerst. At altitudes greater than 1,000 m a.s.l., these species coexist with Araucaria araucana (Molina) K. Koch, between 38-39ºS [3][4][5].…”

Satellite Spectral Property Observations in Chilean Lakes

“…The aim of the present study is to compare spectral property data obtained from LANDSAT-8/OLI in lakes located in lagoons within Huerquehue National Park, which is a mountain zone with native forest of Nothofagus at low altitudes, that is replaced gradually by A. araucana and shrubs at high altitudes and with many lakes associated with different surrounding vegetation [1,3]. These sites are located within a mountain zone with different surrounding landscapes, from Nothofagus forests and shrubs in Tinquilco lake, and Nothofagus and A. araucana forests for Los Condores, Olvidada, Chico, and Del Sacrificio lagoons.…”

“…Los Patos lagoon is located inside A. araucana forest with shrubs, and Las Mercedes and San Manuel lagoons are located in a shrub zone with presence of A. araucana. Many of these lakes are located in zones with serious access problems, and only a few of them are not accessible by mountain paths [1,3]. Many of these lakes are located in zones without easy access, and in this scenario the first exploration by remote sensing techniques would be very useful for begin limnological studies [9,[13][14][15].…”