DOUGLAS FIR PSEUDOTSUGA MENZIESII IN THE AMERICAN NORTH-WEST AND THE ROLE OF RAILWAYS IN ITS EARLY LOGGING

2010 ◽  
Vol 33 (2) ◽  
pp. 107-123 ◽  
Author(s):  
John R. Packhaman ◽  
Colin Faulkner
Keyword(s):  
Pseudotsuga Menziesii ◽  
Douglas Fir ◽  
North West

scholarly journals Effects of soil acidity on Douglas fir seedlings. 2. The role of pH, aluminium concentration and nitrogen nutrition (pot experiment).

1987 ◽  
Vol 35 (4) ◽  
pp. 537-540
Author(s):  
H.P. Smit ◽  
W.G. Keltjens ◽  
N. van Breemen
Keyword(s):  
Pseudotsuga Menziesii ◽  
Soil Acidity ◽  
Nitrogen Nutrition ◽  
Douglas Fir ◽  
Pot Experiment ◽  
Aluminium Concentration

In greenhouse studies, the growth of 1-yr-old Douglas fir (Pseudotsuga menziesii) seedlings decreased and mortality increased with increasing soil acidity when pH was

scholarly journals Probabilistic Provenance Detection and Management Pathways for Pseudotsuga menziesii (Mirb.) Franco in Italy Using Climatic Analogues

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 215
Author(s):  
Maurizio Marchi ◽  
Claudia Cocozza
Keyword(s):  
Pseudotsuga Menziesii ◽  
National Forest Inventory ◽  
Douglas Fir ◽  
Classification Model ◽  
Climatic Data ◽  
Modeling Framework ◽  
North West ◽  
Random Forest Classification ◽  
Seed Sources ◽  
Forest Classification

The introduction of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] in Europe has been one of the most important and extensive silvicultural experiments since the 1850s. This success was mainly supported by the species’ wide genome and phenotypic plasticity even if the genetic origin of seeds used for plantations is nowadays often unknown. This is especially true for all the stands planted before the IUFRO experimentation in the 1960s. In this paper, a methodology to estimate the Douglas-fir provenances currently growing in Italy is proposed. The raw data from the last Italian National Forest Inventory were combined with literature information to obtain the current spatial distribution of the species in the country representing its successful introduction. Afterwards, a random forest classification model was run using downscaled climatic data as predictors and the classification scheme adopted in previous research studies in the Pacific North West of America. The analysis highlighted good matching between the native and the introduction range in Italy. Coastal provenances from British Columbia and the dry coast of Washington were detected as the most likely seed sources, covering 63.4% and 33.8% of the current distribution of the species in the country, respectively. Interior provenances and those from the dry coast of Oregon were also represented but limited to very few cases. The extension of the model on future scenarios predicted a gradual shift in suitable provenances with the dry coast of Oregon in the mid-term (2050s) and afterwards California (2080s) being highlighted as possible new seed sources. However, only further analysis with genetic markers and molecular methods will be able to confirm the proposed scenarios. A validation of the genotypes currently available in Italy will be mandatory as well as their regeneration processes (i.e., adaptation), which may also diverge from those occurring in the native range due to a different environmental pressure. This new information will also add important knowledge, allowing a refinement of the proposed modeling framework for a better support for forest managers.

scholarly journals The role of epicormic shoot production in maintaining foliage in old Pseudotsuga menziesii (Douglas-fir) trees

2001 ◽  
Vol 79 (3) ◽  
pp. 251-264 ◽  
Author(s):  
Hiroaki Ishii ◽  
E David Ford
Keyword(s):  
Pseudotsuga Menziesii ◽  
Maximum Size ◽  
Douglas Fir ◽  
Epicormic Shoots ◽  
Relative Age ◽  
Shoot Production ◽  
Epicormic Shoot ◽  
Five Phases ◽  
Architectural Unit

Shoots and foliage on branches of old Pseudotsuga menziesii (Mirb.) Franco var. menziesii (coastal Douglas-fir) trees are constantly renewed by epicormic shoot production. Epicormic shoots are produced in all parts of the crown, and epicormic buds remain dormant for 5 or 6 years on average. Epicormic shoot production results in reiteration of shoot cluster units (SCUs), an architectural unit of shoot organization within branches. Five phases of SCU development were identified based on relative age structures of regular and epicormic shoots. SCUs produce epicormic branchlets as early as 3 or 4 years of age, and peak production occurred around 6-13 years. Epicormic branchlets occur toward the proximal end of main axes of SCUs, where regular lateral branchlets are no longer producing new shoots. In some lower-crown branches, nearly 50% of shoots and foliage are epicormic shoots. Demographic analysis of SCUs showed that upper-crown branches are still growing in size, while mid- and lower-crown branches have reached maximum size, and are being maintained by reiteration of SCUs. Epicormic shoot production maintains shoots and foliage of old P. menziesii trees after height growth and crown expansion have stopped and may contribute to prolonging tree longevity.Key words: aging, branch growth, epicormic shoots, longevity, Pseudotsuga menziesii, reiteration.

scholarly journals An increasing role of pyrethroid-resistant Anopheles funestus in malaria transmission in the Lake Zone, Tanzania

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nancy S. Matowo ◽  
Jackline Martin ◽  
Manisha A. Kulkarni ◽  
Jacklin F. Mosha ◽  
Eliud Lukole ◽  
...  
Keyword(s):  
Malaria Transmission ◽  
Anopheles Funestus ◽  
Sub Saharan Africa ◽  
North West ◽  
Vector Population ◽  
Lake Zone ◽  
Sub Saharan ◽  
Long Lasting Insecticidal Nets ◽  
Study District

AbstractAnopheles funestus is playing an increasing role in malaria transmission in parts of sub-Saharan Africa, where An. gambiae s.s. has been effectively controlled by long-lasting insecticidal nets. We investigated vector population bionomics, insecticide resistance and malaria transmission dynamics in 86 study clusters in North-West Tanzania. An. funestus s.l. represented 94.5% (4740/5016) of all vectors and was responsible for the majority of malaria transmission (96.5%), with a sporozoite rate of 3.4% and average monthly entomological inoculation rate (EIR) of 4.57 per house. Micro-geographical heterogeneity in species composition, abundance and transmission was observed across the study district in relation to key ecological differences between northern and southern clusters, with significantly higher densities, proportions and EIR of An. funestus s.l. collected from the South. An. gambiae s.l. (5.5%) density, principally An. arabiensis (81.1%) and An. gambiae s.s. (18.9%), was much lower and closely correlated with seasonal rainfall. Both An. funestus s.l. and An. gambiae s.l. were similarly resistant to alpha-cypermethrin and permethrin. Overexpression of CYP9K1, CYP6P3, CYP6P4 and CYP6M2 and high L1014S-kdr mutation frequency were detected in An. gambiae s.s. populations. Study findings highlight the urgent need for novel vector control tools to tackle persistent malaria transmission in the Lake Region of Tanzania.

scholarly journals The role of accommodation environments in student mental health and wellbeing

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Joanne D. Worsley ◽  
Paula Harrison ◽  
Rhiannon Corcoran
Keyword(s):  
Mental Health ◽  
First Year ◽  
Student Mental Health ◽  
North West ◽  
Human Element ◽  
Health And Wellbeing ◽  
Physical Attributes ◽  
Attachment To Place ◽  
Pastoral Staff

Abstract Background Due to the increasing concern over student mental health and wellbeing, attention has turned to the matter of creating environments, communities, and institutions which enable students to flourish. Methods To explore the role of accommodation environments in first year student mental health and wellbeing, eight focus groups were conducted in two universities in North West England and analysed using thematic analysis. Results Three overarching themes were identified: ‘The betwixt space’; ‘Accommodations as vessels to cultivate friendships and communities’; and ‘The importance of accommodation-based pastoral staff’. As attachment to place and relationships with significant others are disrupted by the transition, this leaves young people vulnerable whilst they go through a process to re-attach to new people and a new environment, and loneliness and social isolation were keenly felt during this period. Physical attributes of place that prevent social cohesion further exacerbated feelings of loneliness. Conclusions As it is common for students to withdraw physically and psychologically when they do not form friendships within their flat, accommodation-based pastoral staff have an important role to fulfil. Although these findings demonstrate the importance of the human element within accommodation, designing places that facilitate community, a sense of we-ness, and belonging is crucial.

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