Effects of heavy grazing on the microclimate of a humid grassland mountain ecosystem: Insights from a biomass removal experiment

Montenegro-Díaz, Paola; Célleri, Rolando; Wilcox, Bradford P.; Carrillo‐Rojas, Galo

doi:10.1016/j.scitotenv.2022.155010

Cited by 11 publications

(3 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These trees demand substantially more water than native species, leading to water reserve declines [135,136], displacement of native ora and fauna, and soil sterility [137,138]. Previous studies have shown that LULC changes in uence the broader climate of South America and the speci c microclimate of paramo ecosystems [139,140], altering land surface albedo, thereby impacting precipitation and surface temperature. For example, afforestation decreases re ectivity and increases radiant energy absorption [141], particularly with forest genera like Eucalyptus and Pinus [142].…”

Section: Coal Miningmentioning

confidence: 99%

Paramos in Peril: case study on a blue gold hotspot of central Colombia

Murad,

Pearse,

Huguet

2024

Preprint

View full text Add to dashboard Cite

Paramos, unique and biodiverse ecosystems found solely in the high mountain regions of the tropics, are under threat. Despite their crucial role as primary water sources and significant carbon repositories in Colombia, they are deteriorating rapidly and garner less attention than other vulnerable ecosystems like the Amazon rainforest. Their fertile soil and unique climate make them prime locations for agriculture and cattle grazing, often coinciding with economically critical deposits such as coal which has led to a steady decline in paramo area. Anthropic impact was evaluated using multispectral images from Landsat and Sentinel over 37 years, on the Guerrero and Rabanal paramos in central Colombia which have experienced rapid expansion of mining and agriculture. Our analysis revealed that since 1984, the Rabanal and Guerrero paramos have lost 47.96% and 59.96% of their native vegetation respectively, replaced primarily by crops, pastures, and planted forests. We detected alterations in the spectral signatures of native vegetation near coal coking ovens, indicating a deterioration of paramo health and potential impact on ecosystem services. Consequently, human activity is reducing the extent of paramos and their efficiency as water sources and carbon sinks, potentially leading to severe regional and even global consequences.

show abstract

Section: Coal Miningmentioning

confidence: 99%

Paramos in Peril: case study on a blue gold hotspot of central Colombia

Murad,

Pearse,

Huguet

2024

Preprint

View full text Add to dashboard Cite

show abstract

“…We used 12 h for daily sunshine and did not consider data for crops. The albedo was set to 0.14, which is the average of the albedo values that were reported earlier for the Ecuadorian páramo (0.11-0.17; Montenegro-Díaz et al, 2022;Minaya et al, 2018).…”

Section: Water Flux Modelingmentioning

confidence: 99%

Soil–vegetation–water interactions controlling solute flow and chemical weathering in volcanic ash soils of the high Andes

Páez‐Bimos

Molina

Calispa

et al. 2023

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

Abstract. Vegetation plays a key role in the hydrological and biogeochemical cycles. It can influence soil water fluxes and transport, which are critical for chemical weathering and soil development. In this study, we investigated soil water balance and solute fluxes in two soil profiles with different vegetation types (cushion-forming plants vs. tussock grasses) in the high Ecuadorian Andes by measuring soil water content, flux, and solute concentrations and by modeling soil hydrology. We also analyzed the role of soil water balance in soil chemical weathering. The influence of vegetation on soil water balance and solute fluxes is restricted to the A horizon. Evapotranspiration is 1.7 times higher and deep drainage 3 times lower under cushion-forming plants than under tussock grass. Likewise, cushions transmit about 2-fold less water from the A to lower horizons. This is attributed to the higher soil water retention and saturated hydraulic conductivity associated with a shallower and coarser root system. Under cushion-forming plants, dissolved organic carbon (DOC) and metals (Al, Fe) are mobilized in the A horizon. Solute fluxes that can be related to plant nutrient uptake (Mg, Ca, K) decline with depth, as expected from biocycling of plant nutrients. Dissolved silica and bicarbonate are minimally influenced by vegetation and represent the largest contributions of solute fluxes. Soil chemical weathering is higher and constant with depth below tussock grasses but lower and declining with depth under cushion-forming plants. This difference in soil weathering is attributed mainly to the water fluxes. Our findings reveal that vegetation can modify soil properties in the uppermost horizon, altering the water balance, solute fluxes, and chemical weathering throughout the soil profile.

show abstract

“…Moss substrate water capacity had a non-significant, positive correlation with germination rate (Figure 31). Díaz et al, 2022;Vaieretti et al, 2018). While Scott (1962) presented evidence of increased ground temperatures near tussocks compared to distant, his experiment was conducted so differently as to not be comparable to mine.…”

Section: Trait Relationshipsmentioning

confidence: 99%

Moss Matters: Unravelling the intricate web of interactions between mosses, microclimate, and seed germination in New Zealand's alpine ecosystems

Bell-Butler

View full text Add to dashboard Cite

Mosses are abundant throughout the world in a variety of ecosystems and help regulate water balance by mediating water storage and release. The effects of vascular vegetation are relatively well-known and their ability to alter temperature and moisture conditions at a fine scale has been well-studied. However, limited research has been undertaken, particularly in New Zealand, into the ecological relationships and effects of any bryophytes, including mosses. In grasslands, including New Zealand alpine tussock, mosses are highly important for ecosystem functioning, aiding in water balance regulation. As water availability is a crucial factor for many ecosystem processes, including the germination and growth of seedlings, the presence, absence, or species of moss may have an influence on microclimate, and thus, vascular plants. The degree to which a given moss affects microclimate has been linked to quantifiable traits, which may vary highly both within and among species. My thesis aimed to understand how the functional traits of bryophytes can inform their role in microclimate mediation and the germination of vascular plants in New Zealand tussock grasslands. In addition, I sought to examine how moss traits varied across climatic gradients, especially levels of precipitation.I measured soil, ground surface, and air temperature, and soil moisture at Cardrona Alpine Resort, Central Otago, using 50 data loggers placed across 13 sites. I then compared how these abiotic factors varied with the presence of a moss (Polytrichum juniperinum), proximity to snow tussock (Chionochloa), and with topography (ridge, valley), over a summer growing season. I also collected and measured morphological and functional traits of 249 specimens of 11 moss species collected from grasslands throughout Canterbury and Otago, focussing on traits important for water relations. I then tested the effects of mosses with different traits on the germination of the exotic pest plant, Pilosella officinarum, using seven moss species as substrates compared to bare soil. Water holding capacity, colony density, and water retention ability were highly variable within and among moss species. Some specimens were able to take up ~175 % of their dry mass (Polytrichum juniperinum), others over 2000 % (Hypnum cupressiforme), and desiccation time (to 50 % water capacity) ranged from 6.4 to 271 hours. Colony density varied over two orders of magnitude. There were distinct differences in all functional traits among species and some among groups of species delimited by growth form; wefts were the least dense and had the greatest water holding capacities, while cushions had the shallowest colonies compared to both wefts and turfs.I demonstrated significant differences in ground surface and soil temperatures in microsites that were near or far from individual tussock grasses and those that were on a ridge compared to in a valley. Being near a tussock or in a valley reduced fluctuations and extremes of temperature at the ground surface and in the soil. Moss did not have a detectable effect on microclimate. This may be due to the species present at the site I tested, P. juniperinum, which was a low turf with potentially little ability to affect water storage and temperature insulation, compared to other species. P. juniperinum had very high colony density, a trait linked to poor thermal insulative properties, and was the least able to take up and retain substantial amounts of water. This likely reduces its efficacy as a regulator between the weather and the microclimate.Germination rate of Pilosella officinarum seeds was highest on the bare soil control compared to on any moss species. Seedling growth (per pot biomass) was lower in moss in general compared to bare soil and varied among moss species. Smaller, shallower colonies, such as those of Polytrichum juniperinum, were better substrates for seeds than deep turfs, such as Polytrichastrum alpinum. One relatively large species, Sanionia uncinata, was also nearly as good a substrate as the bare soil control and did not differ significantly in germination rate.My results support the hypothesis that mosses can influence the germination of vascular plants, and that the effects may be mediated by quantifiable traits. They also show that tussock grassland microclimates vary at a scale of metres, mediated by vascular vegetation and topography. I demonstrated both intra- and inter-species-level trait variability in mosses, but findings did not suggest broad patterns at either level when considered across climatic gradients. My findings, in addition to previous ecological studies, indicate that mosses have important ecological functions and their removal when habitats are disturbed likely has impacts on ecosystem function, particularly with respect to seed germination.

show abstract

Effects of heavy grazing on the microclimate of a humid grassland mountain ecosystem: Insights from a biomass removal experiment

Cited by 11 publications

References 42 publications

Paramos in Peril: case study on a blue gold hotspot of central Colombia

Paramos in Peril: case study on a blue gold hotspot of central Colombia

Soil–vegetation–water interactions controlling solute flow and chemical weathering in volcanic ash soils of the high Andes

Moss Matters: Unravelling the intricate web of interactions between mosses, microclimate, and seed germination in New Zealand's alpine ecosystems

Contact Info

Product

Resources

About