M.Sc. AWARDED 2007

M.Sc. Study at the University of Bangor

Effect of future predicted summer drought on the growth of two provenances of pedunculate oak

Welcome to a journey that shaped the foundation of my research trajectory in environmental and natural resources science. In 2007, I completed my MSc at the University of Wales, Bangor, investigating how predicted future summer drought conditions could influence the growth of Quercus robur (pedunculate oak)—a cornerstone species in European temperate forests.

This project allowed me to explore not only the physiological responses of oak seedlings to water stress but also the broader implications of climate change for forest sustainability and provenance selection in reforestation and afforestation efforts.

Why Pedunculate Oak?

Quercus robur is ecologically and economically significant across Europe. However, climate models project longer and more intense drought periods during the growing season. This raised an important question:

How will these changes affect forest species traditionally adapted to temperate, moist environments?

My thesis addressed this by comparing two genetically distinct provenances of Q. robur under simulated drought conditions. The goal was to understand resilience strategies and assess potential differences in adaptive capacity.

Objectives of My Research

To investigate the impact of controlled drought conditions on the growth performance of two Q. robur provenances.
To assess water use, growth rate, and physiological response during a simulated drought event.
To identify which provenance shows greater drought tolerance and potential for future forestry strategies.

Methodology in Brief

The study involved a controlled experiment using two provenances—one from the UK and another from Eastern Europe. I subjected them to two watering regimes:
Control: Regular watering throughout the season.
Drought: Simulated summer drought with no watering for a specified period.
Over the course of the experiment, I monitored:
Biomass production
Height and diameter growth
Leaf wilting and survival
Soil moisture and root-to-shoot ratio

Key Findings and Insights

Provenance Variation Matters: The eastern European provenance showed a stronger capacity to maintain biomass under drought conditions, indicating potential for future planting programs in drier climates.
Growth Trade-offs: While both provenances suffered underwater stress, their adaptive strategies differed—some focusing on conservative water use, others on rapid early growth.

Forest Management Implications: Results support integrating climate-adaptive provenance selection into reforestation planning, especially under IPCC-projected drought scenarios.

Relevance to Current Research and Future Work

This thesis continues to inform my ongoing research in hydrogeology, hydrochemistry, and water resource sustainability. It intersects with broader themes like:

Climate-resilient forest ecosystems
Biodiversity conservation under climate stress
Sustainable forestry and provenance selection
Groundwater-plant interactions under drought

I invite students and collaborators who are interested in the impact of climate extremes on natural ecosystems to reach out—especially those working on the nexus of hydrology, ecology, and forestry.

Download Full Thesis

You can explore the full thesis here (link to be embedded once hosted) for a detailed methodology, data interpretation, and discussion.

Let’s Collaborate

If you're a student or researcher with shared interests in:

Forest vulnerability and adaptation
Drought simulation and plant physiology
Sustainable land and water management

… then I’d be glad to hear from you. Together, we can advance knowledge on ecosystem resilience in an era of accelerating climate change.

M.Sc. QUALIFICATION DETAILS

M.Sc. Thesis Details:

TITLE: Effect of future predicted summer drought on the growth of two provenances of pedunculate oak

AUTHOR: Nabaz I Mohammed

ISSN:

AWARDING BODY: University of Bangor

CURRENT INSTITUTION: University of Duhok

DATE AWARDED: Oct 2007

Full Text Link: [PLEASE CLICK TO VIEW THE FULL TEXT OF MY M.Sc.]

SUPERVISOR: Dr. C.M. Cahalan

SPONSOR:

QUALIFICATION NAME: Degree of Master of Environmental Forestry

QUALIFICATION LEVEL: M.Sc.

LANGUAGE OF THE THESIS: English

Citation to this work:

Mohammed, N.I., 2007. Effect of future predicted summer drought on the growth of two provenances of pedunculate oak (Quercus robur L.). MSc thesis, University of Wales, Bangor.

Abstract:

Two provenances of Quercus robur L., from seed zones 405 and 109 representing South-east England (P1) and South-east Scotland (P2) respectively, were assessed for variation in drought tolerance, since potential climate change may result in summer droughts in much of Great Britain in the near future. Three watering treatments, W1, W2 and W3, corresponding to different climate change scenarios, were applied to one-year-old seedlings. The two provenances were grown in two different experiments. A randomised block design was used for each experiment, with watering treatments randomly assigned to sub-plot in three blocks to each experiment separately. A total of 90 Quercus robur seedlings in each experiment and 180 seedlings in total were evaluated for height growth, diameter growth, relative height growth, relative diameter growth, dry weight of leaf, branch and root, moisture content of leaf, branch and root, and stem: root ratio. The provenance trial was conducted at Henfaes, which is the research site of the School of the Environment and Natural Resources, University of Wales, Bangor, for the duration of eight weeks.

It was found that the both provenances suffered from water stress during the experiment. Water stress affected the SE England provenance significantly in relative height growth, relative diameter growth, shoot: root ratio and moisture content of leaf, branch and root. In contrast, there were significant differences only in relative diameter growth and moisture content of branch in the SE Scotland provenance. It was found that the SE Scotland provenance performed better than SE England provenance in relative height growth, shoot: root ratio and moisture content of leaf, branch and root, in terms of the percentage decrease from treatment W1 to treatment W3. The SE England provenance showed slightly better relative height growth and significantly greater dry weight of leaf. It was also found that the extent to which SE England provenance suffered from drought conditions was much greater than that of SE Scotland provenance.

Although the SE Scotland provenance performed better than the SE England provenance in many traits, it is difficult to draw firm conclusions based on this provenance trial, which was conducted for a short period of time. It is recommended that other factors associated with climate change, like temperature, elevated CO2 and humidity, are considered when conducting provenance trials, which should have the maximum practical number of provenances and be carried out over a longer period.

Keywords:

Quercus robur, climate change, drought simulation, provenance variation, forest adaptation, water stress, environmental resilience, sustainable forestry, plant-water interactions

Reference List:

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