Cold Hardiness of Select Apple Cider Cultivars in Canada

Author(s):  
John A. Cline ◽  
Amanda Beneff ◽  
A. Michelle Edwards

There is increasing interest in growing European origin apple cultivars for the production of hard cider in Canada; however, little is known about their winter hardiness. Eleven promising cider cultivars were evaluated for cold hardiness over two consecutive winters and compared with the winter tender cultivar 'Golden Delicious’. Sections of the current season's dormant shoots were frozen in a series of test temperatures ranging from -20°C to -40°C in a programmable freezer. Xylem tissue browning ratings were used to assess injury after thawing. The temperature of incipient damage (TID), the warmest temperature at which 1-yr-old shoot segments begin to show injury, was obtained from tissue browning curves using non-linear regression. TID varied significantly among cultivars and between sampling years. Overall, the cultivars could be classified according to relative winter hardiness as follows: Ashmead’s Kernel, Bramley’s Seedling (very tender) < Calville Blanc d’Hiver, Porter’s Perfection, Bulmer’s Norman (intermediate) < Crimson Crisp, GoldRush, Golden Delicious, Enterprise, Yarlington Mill, Enterprise (hardy) < Golden Russet (hardy). These data indicate nearly a 10oC range in winter hardiness amongst the 11 cultivars studied, depending on the sampling date. Ashmead’s Kernel and Bramley’s Seedling appear to be particularly winter tender, whereas Bulmer's Norman, Porter's Perfection, and Calville Blanc d'Hiver demonstrated less hardiness during three of the four sampling dates. Based upon these findings, it would be prudent to consult long-term climate normals and consider the frequency of extreme weather events for potential susceptibility to winter injury, particularly prior to establishing more injury-prone cultivars.

2018 ◽  
Vol 2 (1) ◽  
pp. 9-24
Author(s):  
Edoardo Bertone ◽  
Oz Sahin ◽  
Russell Richards ◽  
Anne Roiko

Abstract A decision support tool was created to estimate the treatment efficiency of an Australian drinking water treatment system based on different combinations of extreme weather events and long-term changes. To deal with uncertainties, missing data, and nonlinear behaviours, a Bayesian network (BN) was coupled with a system dynamics (SD) model. The preliminary conceptual structures of these models were developed through stakeholders' consultation. The BN model could rank extreme events, and combinations of them, based on the severity of their impact on health-related water quality. The SD model, in turn, was used to run a long-term estimation of extreme events' impacts by including temporal factors such as increased water demand and customer feedback. The integration of the two models was performed through a combined Monte Carlo–fuzzy logic approach which allowed to take the BN's outputs as inputs for the SD model. The final product is a participatory, multidisciplinary decision support system allowing for robust, sustainable long-term water resources management under uncertain conditions for a specific location.


2021 ◽  
Author(s):  
◽  
Diana de Alwis

<p>Dramatic increase of economic losses from Natural disasters derail economic and human development in many places. This dissertation sheds light on natural disaster risk and short-term and long-term household wellbeing after disasters. It is composed of three empirical studies of Sri Lanka. The first study examines the impacts of frequently occurring extreme weather events on individual health and health care cost using national household data. The analysis shows that local floods and droughts impose a significant risk to health when individuals are exposed directly and their communities indirectly to these hazards. These risks are associated with the land-use in the affected regions and the status of access to sanitation and hygiene. Health risks due to flood and drought cause a considerable economic burden on the private and public health care sectors. Finally, we learn that recurring extreme weather events may potentially be sources of significant health risk and economic cost to a rapidly growing developing country that call for alternative policies focusing on the socio-economic environment, and land use to manage these health risks. The second study estimates a difference- in- difference (DID) model to examine the 2004 Indian Ocean tsunami’s long-term impacts on household wellbeing in Sri Lanka. The study finds a strong association between area-wide tsunami disaster shock and increases in household income and consumption in the long-term. The increase in consumption is much smaller than the observed increase in income; the study reveals an increase in food consumption and only a marginal increase in non-food consumption. The third study analyses the 2004 tsunami recovery’s impact on income distribution across households in the long-term in Sri Lanka using quantile difference-in-difference methods and inequality measures. Recovery of household income is observed across the entire distribution of affected households. The income recovery is skewed to low-income households; the affected regions appear more income-equal ex-post compared to the unaffected regions. A similar pattern appears for consumption. Finally, the findings in the second and third studies show a potential for a long-lasting and successful recovery from a catastrophic disaster.</p>


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Serhan Cevik ◽  
Manuk Ghazanchyan

Abstract While the world’s attention is on dealing with the COVID-19 pandemic, climate change remains a greater existential threat to vulnerable countries that are highly dependent on a weather-sensitive sector like tourism. Using a multidimensional index, this study investigates the long-term impact of climate change vulnerability on international tourism in a panel of 15 Caribbean countries over the period 1995–2017. Empirical results show that climate vulnerability already has a statistically and economically significant negative effect on international tourism revenues across the region. As extreme weather events are becoming more frequent and severe over time, our findings indicate that the Caribbean countries need to invest more in adaptation and mitigation in order to reduce vulnerabilities.


2020 ◽  
Vol 20 (243) ◽  
Author(s):  
Serhan Cevik ◽  
Manuk Ghazanchyan

While the world’s attention is on dealing with the COVID-19 pandemic, climate change remains a greater existential threat to vulnerable countries that are highly dependent on a weather-sensitive sector like tourism. Using a novel multidimensional index, this study investigates the long-term impact of climate change vulnerability on international tourism in a panel of 15 Caribbean countries over the period 1995–2017. Empirical results show that climate vulnerability already has a statistically and economically significant negative effect on international tourism revenues across the region. As extreme weather events are becoming more frequent and severe over time, our findings indicate that the Caribbean countries need to pursue comprehensive adaptation policies to reduce vulnerabilities to climate change.


2019 ◽  
Vol 4 (4) ◽  
pp. 65 ◽  
Author(s):  
Pytharouli ◽  
Michalis ◽  
Raftopoulos

Unprecedented flooding events put dams and downstream communities at risk, as evidenced by the recent cases of the Oroville and Whaley bridge dams. Empirical models may describe expected ‘normal’ dam behaviour, but they do not account for changes due to recurring extreme weather events. Numerical modelling provides insights into this, but results are affected by the chosen material properties. Long-term field monitoring data can help with understanding the mechanical behaviour of earthfill dams and how this is affected by the environment over decades. We analyse the recorded settlements for one of the largest earthfill dams in Europe. We compare the evolution of these settlements to the reservoir level, rainfall, and the occurrence of earthquakes for a period of 31 years after first impoundment. We find that the clay core responds to the reservoir fluctuations with an increasing (from 0 to 6 months) time delay. This is the first time that a change in the behaviour of a central clay core dam, as observed from field data, is reported in the international literature. Seepage rates, as recorded within the drainage galleries, are directly affected by cumulative rainfall depths exceeding 67 mm per fortnight.


2020 ◽  
Author(s):  
Md Asif Rahman

Alkali-silica reaction (ASR) is one of the common sources of concrete damage worldwide. The surrounding environment, namely, temperature and humidity greatly influence the alkali-silica reaction induced expansion. Global warming (GW) has caused frequent change in the climate and initiated extreme weather events in recent years. These extreme events anticipate random change in temperature and humidity, and convey potential threats to the concrete infrastructure. Moreover, external loading conditions also affect the service life of concrete. Thus, complex mechanisms of ASR under the impact of seasonal change and global warming require a precise quantitative assessment to guide the durable infrastructure materials design practices. Despite decades of phenological observation study, the expansion behavior of ASR under these situations remains to be understood for capturing the ASR damage properly. Within this context this research focuses on the mathematical model development to quantify and mitigate ASR-induced damage. Mesoscale characteristics of ASR concrete was captured in the virtual cement-concrete lab where the ASR gel-induced expansion zone was added as a uniform thickness shell. Finite element method (FEM) was used to solve the ASR formation and expansion evolution. The results of this study are presented in the form of one conference and their journal manuscripts. The first manuscript focuses on the development of the governing equations based on the chemical formulas of alkali-silica reaction to account for the ASR kinetics and swelling pressure exerted by the ASR expansion. There is a fluid flow and mass transfer in the concrete domain due to ASR gel associated from ASR kinetics. This paper involves derivation of the mass and momentum balance equation in terms of the thermo-hygro-mechanical (THM) model. THM model accounts for thermal expansion and hygroscopic swelling in addition to traffic loads to represent volumetric change in the concrete domain. The second manuscript is a case study based on different cement-aggregate proportions and alkali hydroxide concentrations. It is important to know how ASR evolves under variable concentration of the chemical species. The simulated results show that high concentration of hydroxide ion in concrete initiates more reaction and damage in concrete. Also chemical reaction moves to the right direction with low cement to aggregate ratio which means ASR expansion depends on the availability of the reactive aggregates in the concrete domain. The third manuscript attempts to develop a simplified ASR model that integrates chemo-physio-mechanical damage under stochastic weather impact. Stochasicity incorporates the random behavior of surrounding nature in the model. The simulated results elucidate that ASR expansion is more severe under the influence of global warming and climate change. This will support long-term damage forecasts of concrete subjected to extreme weather events. The fourth manuscript focuses on the quantification of mechanical damage under ASR expansion and a dedicated mitigation scheme to minimize it. Added creep loads and physics identify the role of creep damage on ASR expansion. The results from this paper confirms that the ASR-induced damage significantly minimize the load carrying capacity of concrete. It directly affects the compressive strength, tensile strength, and modulus of elasticity of concrete. Damage in aggregates domain is more than the mortar phase under the creep loadings. Among many supplementary materials, fly ash is the most effective in minimizing ASR expansion and damage. This work also includes a petrographic comparison between different mineral types collected from different locations to identify the reactivity of certain aggregates. Thus, the final outcome of this research is a complete model which is a conclusive solution to the long-term ASR damage prediction. The validated model provides better understanding of ASR kinetics from mesoscale perspective. The developed model can potentially accelerate the precise prediction of concrete service life and mitigation schemes as well as can be used as an alternative scope to the costly laboratory tests methods.


2013 ◽  
Vol 72 (2) ◽  
pp. 30 ◽  
Author(s):  
Külli Kangur ◽  
Peeter Kangur ◽  
Kai Ginter ◽  
Kati Orru ◽  
Marina Haldna ◽  
...  

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