Global climate change and tree nutrition: effects of elevated CO2 and temperature

Although tree nutrition has not been the primary focus of large climate change experiments on trees, we are beginning to understand its links to elevated atmospheric CO2 and temperature changes. This review focuses on the major nutrients, namely N and P, and deals with the effects of climate change on the processes that alter their cycling and availability. Current knowledge regarding biotic and abiotic agents of weathering, mobilization and immobilization of these elements will be discussed. To date, controlled environment studies have identified possible effects of climate change on tree nutrition. Only some of these findings, however, were verified in ecosystem scale experiments. Moreover, to be able to predict future effects of climate change on tree nutrition at this scale, we need to progress from studying effects of single factors to analysing interactions between factors such as elevated CO2, temperature or water availability

Bio-energy retains its mitigation potential under elevated CO2

Background If biofuels are to be a viable substitute for fossil fuels, it is essential that they retain their potential to mitigate climate change under future atmospheric conditions. Elevated atmospheric CO2 concentration [CO2] stimulates plant biomass production; however, the beneficial effects of increased production may be offset by higher energy costs in crop management. Methodology/Main findings We maintained full size poplar short rotation coppice (SRC) systems under both current ambient and future elevated [CO2] (550 ppm) and estimated their net energy and greenhouse gas balance. We show that a poplar SRC system is energy efficient and produces more energy than required for coppice management. Even more, elevated [CO2] will increase the net energy production and greenhouse gas balance of a SRC system with 18%. Managing the trees in shorter rotation cycles (i.e. 2 year cycles instead of 3 year cycles) will further enhance the benefits from elevated [CO2] on both the net energy and greenhouse gas balance. Conclusions/significance Adapting coppice management to the future atmospheric [CO2] is necessary to fully benefit from the climate mitigation potential of bio-energy systems. Further, a future increase in potential biomass production due to elevated [CO2] outweighs the increased production costs resulting in a northward extension of the area where SRC is greenhouse gas neutral. Currently, the main part of the European terrestrial carbon sink is found in forest biomass and attributed to harvesting less than the annual growth in wood. Because SRC is intensively managed, with a higher turnover in wood production than conventional forest, northward expansion of SRC is likely to erode the European terrestrial carbon sink

Development of multi-functional streetscape green infrastructure using a performance index approach

This paper presents a performance evaluation framework for streetscape vegetation. A performance index (PI) is conceived using the following seven traits, specific to the street environments - Pollution Flux Potential (PFP), Carbon Sequestration Potential (CSP), Thermal Comfort Potential (TCP), Noise Attenuation Potential (NAP), Biomass Energy Potential (BEP), Environmental Stress Tolerance (EST) and Crown Projection Factor (CPF). Its application is demonstrated through a case study using fifteen streetvegetation species from the UK, utilising a combination of direct field measurements and inventoried literature data. Our results indicate greater preference to small-to-medium size trees and evergreen shrubs over larger trees for streetscaping. The proposed PI approach can be potentially applied two-fold: one, for evaluation of the performance of the existing street vegetation, facilitating the prospects for further improving them through management strategies and better species selection; two, for planning new streetscapes and multi-functional biomass as part of extending the green urban infrastructure

Plant nutrition -Food security and sustainability of agro-ecosystems

Abstract Rising levels of atmospheric CO 2 may change root production, root turnover and ecosystem carbon balance. In order to quantify these possible alterations over longer time period and at an ecosystem level a novel technique of air CO 2 enrichment was applied to a plantation of three fast growing Populus species. Root production and turnover were measured both by auger and ingrowth coring methods. Two years into the experiment both methods applied show increased production of fine and coarse roots under elevated CO 2 conditions for all three clones utilised. These results suggest that future levels of atmospheric CO 2 will have to be taken into account when constructing a carbon budget of an ecosystem

Estimation of productivity in pine and oak forests in northern Portugal using Biome-BGC

Studies about the productivity of forest ecosystems help to quantify sequestered carbon and provide data that are used in forest management. Forests in northern Portugal are an important economic resource, but their productivity in scenarios of future climate change is not yetwell understood. The objectives of this study were to evaluate and compare simulated net primary production (NPP) andNPPbased onmeasured data of twotree species located in the Vila Real district forests, pine (Pinus pinaster Aiton) and oak (Quercus pyrenaica Willd.) and assess their simulatedNPPin diverse climate conditions, including future climate scenariosandincreasing atmospheric CO2 concentrations. An ecosystem process model, Biome-BGC, which simulates carbon, nitrogen and water cycles of forest ecosystems close to equilibrium conditions, was used to examine the importance of site and ecophysiological factors on the productivity of these forests. Climate change scenarios and increased CO2 concentrations were tested to explore potential responses of the studied species. The model provided good estimates of NPP. There was a strong correlation between the simulated and measured NPP values in the pine (15) and oak (15) stands. The NPP of these forests are predicted to increase in the future with a CO2 increase whereas in a climate with higher temperature and lower soil moisture, the NPP will decrease. These results confirm that precipitation is a very important climate variable to growth and productivity in the Mediterranean forest ecosystems. This study also demonstrated the ability of Biome-BGC to accurately simulate forest ecosystems behaviour and encourages the application of model simulations in Portugalinfo:eu-repo/semantics/publishedVersio

A framework for assessing and implementing the co-benefits of nature-based solutions in urban areas

To address challenges associated with climate resilience, health and well-being in urban areas, current policy platforms are shifting their focus from ecosystem-based to nature-based solutions (NBS), broadly defined as solutions to societal challenges that are inspired and supported by nature. NBS result in the provision of co-benefits, such as the improvement of place attractiveness, of health and quality of life, and creation of green jobs. Few frameworks exist for acknowledging and assessing the value of such co-benefits of NBS and to guide cross-sectoral project and policy design and implementation. In this paper, we firstly developed a holistic framework for assessing co-benefits (and costs) of NBS across elements of socio-cultural and socio-economic systems, biodiversity, ecosystems and climate. The framework was guided by a review of over 1700 documents from science and practice within and across 10 societal challenges relevant to cities globally. We found that NBS can have environmental, social and economic co-benefits and/or costs both within and across these 10 societal challenges. On that base, we develop and propose a seven-stage process for situating co-benefit assessment within policy and project implementation. The seven stages include: 1) identify problem or opportunity; 2) select and assess NBS and related actions; 3) design NBS implementation processes; 4) implement NBS; 5) frequently engage stakeholders and communicate co-benefits; 6) transfer and upscale NBS; and 7) monitor and evaluate co-benefits across all stages. We conclude that the developed framework together with the seven-stage co-benefit assessment process represent a valuable tool for guiding thinking and identifying the multiple values of NBS implementation

Does long-term warming affect C and N allocation in a Mediterranean shrubland ecosystem? Evidence from a¹³C and¹⁵N labeling field study

© 2017 In the Mediterranean basin the effects of climate warming on ecosystem functioning will strongly depend on the warming intensity directly but also on its effects on evapotranspiration and nutrient cycling. Climate manipulation experiments under field conditions are a source of unique empirical evidence regarding climate-related modifications of biotic processes. A field night-time warming experiment, simulating the predicted near-future increase in ambient temperatures (+0.3 up to 1 °C), was established in a Mediterranean shrub community located in Porto Conte (Italy) in 2001. After 11 years of continuous treatment, we labeled the dominant shrub Cistus monspeliensis with 13 CO 2 and studied the dynamics of the label allocation between aboveground and belowground pools and fluxes in warmed and ambient plots within 2 weeks of the chasing period. The interactions between C and N metabolism were assessed by parallel labeling of soil with K 15 NO 3. Most of the assimilated 13 C was respired by Cistus shoots (28–51%) within two weeks. Cistus under warming respired more 13 C label and tended to allocate less 13 C to leaves, branches and roots. The higher C and N content in microbial biomass in warming plots, combined with the higher N content in plant tissues and soil, evidenced a greater N mobilization in soil and a better nutrient status of the plants as compared to the ambient treatment. Acceleration of N cycling is probably responsible for higher respiratory C losses, but combined with the reduction in the number of frost days, should also positively affect plant photosynthetic performance. We conclude that, although Cistus plants are already growing in conditions close to their thermal optimum, long-term warming will positively affect the performance of this species, mainly by reducing the nutrient constraints. This positive effect will highly depend on the frequency and amount of rain events and their interactions with soil N content

Работа с текстом по специальности как средство обучения языку профессионального общения

The quickly rising atmospheric carbon dioxide (CO2)‐levels, justify the need to explore all carbon (C) sequestration possibilities that might mitigate the current CO2 increase. Here, we report the likely impact of future increases in atmospheric CO2 on woody biomass production of three poplar species (Populus alba L. clone 2AS‐11, Populus nigra L. clone Jean Pourtet and Populus×euramericana clone I‐214). Trees were growing in a high‐density coppice plantation during the second rotation (i.e., regrowth after coppice; 2002–2004; POPFACE/EUROFACE). Six plots were studied, half of which were continuously fumigated with CO2 (FACE; free air carbon dioxide enrichment of 550 ppm). Half of each plot was fertilized to study the interaction between CO2 and nutrient fertilization. At the end of the second rotation, selective above‐ and belowground harvests were performed to estimate the productivity of this bio‐energy plantation. Fertilization did not affect growth of the poplar trees, which was likely because of the high rates of fertilization during the previous agricultural land use. In contrast, elevated CO2 enhanced biomass production by up to 29%, and this stimulation did not differ between above‐ and belowground parts. The increased initial stump size resulting from elevated CO2 during the first rotation (1999–2001) could not solely explain the observed final biomass increase. The larger leaf area index after canopy closure and the absence of any major photosynthetic acclimation after 6 years of fumigation caused the sustained CO2‐induced biomass increase after coppice. These results suggest that, under future CO2 concentrations, managed poplar coppice systems may exhibit higher potential for C sequestration and, thus, help mitigate climate change when used as a source of C‐neutral energy