Effects of Nutrient Limitations and Watershed Inputs on Community Respiration in a Deep, Tropical Lake: Comparison of Pelagic and Littoral Habitats

Abstract

Community respiration and nutrient limitation are frequently studied in pelagic habitats; however, comparisons of these processes between littoral and pelagic habitats are less common and do not exist from mountain lake ecosystems in the tropics. Community respiration was measured in the littoral benthic and pelagic habitats of a deep, endorheic mountain lake in Guatemala. Community respiration rates were quantified using biochemical oxygen demand within a temperature controlled, dark, laboratory incubation. Community respiration was measured in the pelagic habitat in response to inorganic nitrogen, phosphorus, nitrogen and phosphorus, glucose, five different soils, and sewage additions and in the littoral habitat in response to inorganic nitrogen, phosphorus, nitrogen and phosphorus, and sewage additions. During all periods, community respiration was higher and more variable in the littoral habitat than in the pelagic habitat. The additions of nitrogen, phosphorus, and nitrogen and phosphorus had no effect on community respiration, in either habitat. Glucose and four of the five soil additions from various watershed vegetation types significantly stimulated community respiration in the pelagic habitat. Sewage additions elicited the highest response in both pelagic and littoral habitats. We demonstrate that community respiration in a tropical montane lake is not limited by inorganic nitrogen or phosphorus and is not colimited by both nutrients combined. Treatments containing organic carbon and organic nutrients were significant stimulators of community respiration; therefore, organic carbon is likely limiting community respiration in Lake Atitlán.

Multi-level storylines for participatory modeling – involving marginalized communities in Tz'olöj Ya', Mayan Guatemala

“…2) (Ferráns et al, 2018;Newhall, 1987). Lake Atitlán is a warm monomictic lake that experiences two main seasons: (1) dry from November to April and (2) wet from May to October (Weiss, 1971). More than 50 % of the watershed consists of steep slopes (Komárek et al, 2013).…”

“…lenging to solve as they are characterized by the complex interactions between biophysical and socio-economic dimensions (van Bruggen et al, 2019;Gunda et al, 2018). Deterioration of lake ecosystems due to cultural eutrophication is especially magnified in developing countries, where governing bodies tend to be more tolerant of practices contributing to aquatic nutrient enrichment (Nixon, 1995;Withers and Haygarth, 2007). To address problematic human-water interactions in developing countries, the bottom-up development of management practices and policies with stakeholders is crucial (Perrone et al, 2020).…”

The interaction of physical structure and nutrient loading drives ecosystem change in a large tropical lake over 40 years

“…Further limiting our understanding of tropical lake nutrient dynamics is a relative lack of long-term monitoring efforts in tropical and subtropical lakes (Sarmento 2012). The largest body of work on tropical lakes are studies of the African Great Lakes (Talling and Lemoalle 1998; Guildford and Hecky 2000; Hecky 2000; Bootsma and Hecky 2003; Llirós et al 2012;), with some notable exceptions such as work done in Lake Atitlan, Guatemala (Corman et al 2015; Weisman et al 2018) and in several Brazilian reservoirs (Pinto Coelho 1998; Tundisi et al 2004). While studies of the African Great Lakes have made invaluable contributions to tropical limnology, the distinct lack of comparable research in other regions of the tropics and in lakes differing in size and stratification regime (Cael and Seekell 2016; Dodds and Whiles 2019) may bias our understanding of tropical limnology towards these unique ecosystems.…”

“…Without long-term datasets, it is difficult to distinguish between intra-annual variability, periodic or semi-periodic inter-annual variability (e.g., changes associated with El Niño-Southern Oscillation), and directional inter-annual changes. While studies of the African Great Lakes (Talling and Lemoalle 1998;Hecky 2000;Bootsma and Hecky 2003), Central American lakes such as Lake Atitlán (Corman et al 2015;Weisman et al 2018) and many Brazilian reservoirs and floodplain lakes (Tundisi et al 1993;Melack et al 2020) among many others, have made considerable contributions to tropical limnology, time series data remain far less common in tropical compared to temperate systems. This is, in part, due to the differences in abundance of lakes at temperate compared to tropical latitudes (Verpoorter et al 2014) and also the legacy of a temperate lake focus in the field of limnology (Kilham and Kilham 1990).…”

Sequestration and Transformation in Chemically Enhanced Treatment Wetlands: DOC, DBPPs, and Nutrients

“…In addition, nutrients and heavy metals can also be removed during coagulation (Aguilar et al 2002;Lee and Westerhoff 2006;El Samrani et al 2008;Akbal and Camcı 2010), leading to their use for eutrophication reduction in lakes and reservoirs (Harper et al 1998;Rydin and Welch 1998;Welch and Cooke 1999;Sherwood and Qualls 2001;Welch and Schrieve 2013). However, removal of nutrients may have important implications on plant nutrient availability, bacterial growth, and wetland processes (Thingstad and Lignell 1997;Poorter and Nagel 2000;Delgado-Baquerizo et al 2017;Weisman et al 2018).…”