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High-altitude wetlands of the Central Andes, locally known as bofedales, provide important ecosystem services, particularly carbon storage, forage provisioning, and water regulation. Local communities have artificially expanded bofedales by irrigating surrounding grasslands to maximise areas for alpaca grazing. Despite their importance, biophysical processes of both natural and artificial bofedales are still poorly studied, which hinders the development of adequate management and conservation strategies. We analyse and compare the vegetation composition, hydrological variables, groundwater chemistry, and soil characteristics of a natural and an artificial bofedal of at least 10 years old in southern Peru, to understand their interrelations and the consequences for ecosystem service provisioning. We do not find statistically significant differences in the soil, water, and vegetation characteristics. Soil organic carbon (SOC) content, which we use as a proxy for carbon storage, is negatively correlated to dissolved oxygen, pH, and soil water temperature. In addition, Non-Metric Multidimensional Scaling analysis shows a positive relation between plant community composition, SOC content, and water electric conductivity. Our results suggest a three-way interaction between hydrological, soil, and vegetation characteristics in the natural bofedal, which also holds for the artificial bofedal. Vegetation cover of two of the most highly nutritious species for alpaca, Lachemilla diplophylla and Lilaeopsis macloviana with 19-22% of crude protein, are weakly or not correlated to environmental variables, suggesting grazing might be obscuring these potential relationships. Given the high economic importance of alpaca breeding for local communities, expanding bofedales artificially appears an effective strategy to enhance their ecosystem services with minimal impact on the ecohydrological properties of bofedales.

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High-elevation grasslands worldwide provide essential hydrological services including water provision, flow regulation, and erosion control. Despite their importance, hydrological research of grasslands in montane regions is usually scarce and disperse, limiting the capacity to improve water resource management. We present a systematic literature review of the hydrological function of high Andean grasslands under conserved, degraded, and restored conditions in ecosystems situated above the tree line in the tropical Andes (páramos, punas, and jalcas). Most hydrological research on these grasslands has been developed in páramos (92%), especially in Ecuador, while research in punas is scarce (6%) despite being the largest grassland extent in the region. For páramos, published literature highlights the importance of conserving grasslands to facilitate water infiltration to soils, which in turn reduces erosive processes. Water-vegetation relations for conserved páramos are well understood, indicating that about 50% of water inputs return to the atmosphere via evapotranspiration, but knowledge about hydrological functions of conserved punas and jalcas is virtually non-existent. Under changing land use, afforestation of grassland ecosystems with exotic tree species, especially pines, reduces soil water storage as well as water yield and flow regulation capacity. Impacts of grazing and agriculture on the hydrological function of páramo grasslands strongly depend on historical land management and current land use practices and are not generalizable. Short-term restoration studies indicate that more than two years are necessary to recover the hydrological function of degraded grasslands, therefore medium and long-term studies are required to determine efficient restoration periods. These knowledge gaps limit the ability to extrapolate and regionalize findings. Future directions aimed to fill them are proposed, and methods successfully used to investigate the hydrology of high Andean grasslands are highlighted. This research not only enlightens what is known about the hydrology of high Andean grasslands, but also seeks to guide future hydrological evaluations to fill identified geographical and topical knowledge gaps precluding improved management of water resources in the tropical Andes.

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Nature-based solutions (NBS) are an increasingly popular approach to water resources management, with a growing number of projects designed to take advantage of landscape effects on water flow. As NBS for water are developed, producing hydrologic information to inform decisions often requires substantial investment in data acquisition and modeling; for this effort to be worthwhile, the information generated must be useful and used. We apply an evaluation framework of salience (type of information), credibility (quality of information), and legitimacy (trustworthiness of information) to assess how hydrologic modeling outputs have been used in NBS projects by three types of decision makers: advocates, implementers, and analysts. Our findings, based on documents and interviews with watershed management programs in South America currently implementing NBS, consider how hydrologic modeling supports two types of decisions for NBS projects: quantifying the hydrologic impact of potential and existing NBS and prioritizing where NBS might be sited within a watershed. To help inform future modeling studies, we identify several problematic assumptions that analysts may make about the credibility of modeled outputs for NBS when advocates and implementers are not effectively engaged. We find that salient, credible, and legitimate results in applications evaluating NBS for water are not always generated in the absence of clear communication and engagement. Integr Environ Assess Manag 2022;18:135-147. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

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Controlled experiments have shown that trees acclimate thigmomorphogenetically to wind-loads by sensing their deformation (strain). However, the strain regime in nature is exposed to a full spectrum of winds. We hypothesized that trees avoid overreacting by responding only to winds which bring information on local climate and/or wind exposure. Additionally, competition for light dependent on tree social status also likely affects thigmomorphogenesis. We monitored and manipulated quantitatively the strain regimes of 15 pairs of beech (Fagus sylvatica) trees of contrasting social status in an acclimated stand, and quantified the effects of these regimes on the radial growth over a vegetative season. Trees exposed to artificial bending, the intensity of which corresponds to the strongest wind-induced strains, enhanced their secondary growth by at least 80%. Surprisingly, this reaction was even greater - relatively - for suppressed trees than for dominant ones. Acclimated trees did not sense the different types of wind events in the same way. Daily wind speed peaks due to thermal winds were filtered out. Thigmomorphogenesis was therefore driven by intense storms. Thigmomorphogenesis is also likely to be involved in determining social status.

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Virot et al. [E. Virot et al., Phys. Rev. E 93, 023001 (2016)10.1103/PhysRevE.93.023001] assert that the critical wind speed at which ⩾50% of all trees in a population break is ≈42 m/s, regardless of tree characteristics. We show that empirical data do not support this assertion, and that the assumptions underlying the theory used by Virot et al. are inconsistent with the biomechanics of trees.

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The environmental wood profile, all over its life cycle, is a subject of interest for industries within the forest sector. Douglas-fir is a wood species with multiple applications and high productivity. In Europe, France is the country with the largest area dedicated to the cultivation of this tree species. This study aims to quantify the Douglas-fir forestry environmental impacts under different management practices performed in France. This study presents detailed life cycle inventories of both intensive and extensive scenarios, including all the processes from site preparation to logging activities. The results showed that stand establishment operations, tending and logging were the main stages responsible for the environmental impacts in both scenarios. The requirement of numerous thinning steps prior to the final cutting, which require machines with large fuel consumption, also had a negative influence. The logging stage, which includes the final cutting and the corresponding forwarding and loading onto trucks, also accounted for a significant contribution to all the categories. When the environmental results were compared with other life cycle studies on pine, eucalyptus and spruce, similar trends were identified in spite of the different management practices (low or high intensive scenarios), system boundaries and forest systems intensity (frequency of activities) considered.

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