Closing Water Cycles in the Built Environment through Nature-Based Solutions: The Contribution of Vertical Greening Systems and Green Roofs

Water in the city is typically exploited in a linear process, in which most of it is polluted, treated, and discharged; during this process, valuable nutrients are lost in the treatment process instead of being cycled back and used in urban agriculture or green space. The purpose of this paper is to advance a new paradigm to close water cycles in cities via the implementation of nature-based solutions units (NBS_u), with a particular focus on building greening elements, such as green roofs (GRs) and vertical greening systems (VGS). The hypothesis is that such “circular systems” can provide substantial ecosystem services and minimize environmental degradation. Our method is twofold: we first examine these systems from a life-cycle point of view, assessing not only the inputs of conventional and alternative materials, but the ongoing input of water that is required for irrigation. Secondly, the evapotranspiration performance of VGS in Copenhagen, Berlin, Lisbon, Rome, Istanbul, and Tel Aviv, cities with different climatic, architectural, and sociocultural contexts have been simulated using a verticalized ET0 approach, assessing rainwater runoff and greywater as irrigation resources. The water cycling performance of VGS in the mentioned cities would be sufficient at recycling 44% (Lisbon) to 100% (Berlin, Istanbul) of all accruing rainwater roof–runoff, if water shortages in dry months are bridged by greywater. Then, 27–53% of the greywater accruing in a building could be managed on its greened surface. In conclusion, we address the gaps in the current knowledge and policies identified in the different stages of analyses, such as the lack of comprehensive life cycle assessment studies that quantify the complete “water footprint” of building greening systems.

Ocean Surface Flux Algorithm Effects on Earth System Model Energy and Water Cycles

Earth system models parameterize ocean surface fluxes of heat, moisture, and momentum with empirical bulk flux algorithms, which introduce biases and uncertainties into simulations. We investigate the atmosphere and ocean model sensitivity to algorithm choice in the Energy Exascale Earth System Model (E3SM). Flux differences between algorithms are larger in atmosphere simulations (where wind speeds can vary) than ocean simulations (where wind speeds are fixed by forcing data). Surface flux changes lead to global scale changes in the energy and water cycles, notably including ocean heat uptake and global mean precipitation rates. Compared to the control algorithm, both COARE and University of Arizona (UA) algorithms reduce global mean precipitation and top of atmosphere radiative biases. Further, UA may slightly reduce biases in ocean meridional heat transport. We speculate that changes seen here, especially in the ocean, could be even larger in coupled simulations.

The Gaps in Environmental Networks Across Latin America

Despite its notable influence on global carbon and water cycles, Latin America accounts for a relatively small share of FLUXNET sites, which limits the representativeness of the network in the region.

Bioética de la fitodepuración de aguas

Bioethics of Water PhytodepurationResumen Basado en principios de permacultura, recuperamos la idea de que el agua es un elemento clave en la trama de la vida, en el planeta Tierra. Somos agua, más que “poseemos” agua en nuestro cuerpo, es la base para reconsiderar la memoria de las estructuras que desde el agua, permiten reproducir los ciclos vitales. Los usos de suelo y formas de habitar actual, podrían mejorar su impacto en el ciclo del agua, utilizando principios de fito-depuración, de bajo costo y tecnología accesible, para permitir más rápida re-vivificación del medio acuoso.Abstract Based on permaculture principles, we recover the idea that water is a key element in the web of life in the Earth. We “are” water, more than we “have” water in our body, it is the basis for reconsidering the memory of the structures that, from the water, allow us to reproduce life cycles. The current ways of living and land uses, could improve their impact on the water cycles, using low-cost phyto-purification principles and accessible technology, to allow faster re-vivification of the wet-lands and all water systems.Key words: Waters (Gray - Black), Phytodepuration, Permaculure, Septic Chamber.

How Forest Degradation Affects Carbon and Water Cycles

Forest degradation may be as widespread as deforestation in the Amazon, but its impact on energy, carbon, and water fluxes is less well understood.

Uncertainty of evapotranspiration fluxes measured with eddy covariance

<p>The project MOMENT (Model Monitoring EveNTs) investigates the interplay between carbon and water cycles with special focus on the impacts of drought and heatwaves as well as their long-term trends. This project aims to investigate new monitoring and modeling methods to explain the interplay between carbon and water cycles of ecosystems on different time and spatial scales.</p><p>To achieve this goal, we need reliable information about the ecosystem and its drivers. We measure, for example, mass and energy exchange between the ecosystem and the lower atmosphere with the eddy covariance method, which allows us to obtain data on a half-hourly scale. Nevertheless, unfavorable weather conditions, as well as malfunctions of the instruments, can lead to a serious amount of data gaps. Different gap-filling methods are available, with the Marginal Distribution Sampling (MDS) by Reichstein et al. (2005) being the most common one. Here, we investigate, how different filling approaches influence the uncertainty of evapotranspiration (ET) data for a German forest. We especially focus on the imputation of evaporation from intercepted canopy water, because open-path EC systems rarely work correctly during and after rain events.</p><p>Even though the EC technique is a well-established method to measure ET at the ecosystem level, many approaches require rather the share of transpiration, such as the validation of some ecosystem models. Partitioning ET into its components is difficult due to the manifold drivers involved, and measuring ecosystem transpiration is challenging due to measurement limitations and assumptions, that have to be made. Therefore, we examine the possibility to retrieve information about the share of transpiration by using EC data only without additional measurement campaigns.</p><p>Reference: <br><span>Reichstein</span>, M. et al.: On the separation of net ecosystem exchange into assimilation and ecosystem respiration: Review and improved algorithm, Glob. Chang. Biol., 11(9), 1424–1439, doi:10.1111/j.1365-2486.2005.001002.x, 2005.</p>