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Forward-looking practices for climate- responsive site preparation, direct seeding, and planting
No full textThe successful establishment and early growth of tree seedlings are critical in shaping the future structure, vitality, and function of forests. These initial stages lay the foundation for the ability of forests to provide multiple benefits, including timber production, car-
bon sequestration, biodiversity conservation, and recreational opportunities. Regenera-
tion strategies must account for a range of environmental and site-specific factors, including soil conditions and the legacy of past land use. Whether new forests are being established on an area devoid of earlier forest cover, e.g., former agricultural land (affor-
estation), on degraded sites, or on forest lands after harvesting or disturbances (refores-
tation or restoration), past land use significantly affects the choice of regeneration methods. Moreover, practical considerations such as regulatory frameworks, the availability of forest reproductive material, and workforce capacity further shape decision-making. Ensuring that newly established forests align with local ecological, economic, and societal needs requires a context-sensitive approach that balances long-
term sustainability with operational realities
Best practices for producing high quality seedlings and establishing main European tree species: Ulmus L. (Ulmus laevis Pall., Ulmus minor Mill., Ulmus glabra Huds.)
No full textUlmus spp. (elms) produce samaras, winged fruits dispersed by wind and water. Flowering starts in late winter or early spring before leafing, allowing fruit maturation by spring. Samaras can be collected directly from trees or by shaking the branches with poles and collecting from the ground. As wind can easily dislodge samaras, collection is best done in calm, sunny, and dry weather. Ulmus produce samaras almost every year, but studies in U. laevis populations in central Spain have shown that seed production in a mast year is up to 24 times greater than in non-masting years (Venturas et al., 2014) with a significant proportion of samaras being empty in non-masting years (Perea et al., 2013). Seeds are kept attached to the samaras, which are not dewinged allowing the whole fruit to be used for nursery seeding (Regent, 1980; Stilinovi�c, 1985)
Quercus pubescens Willd - Best practices for producing high quality seedlings and establishing main European tree species
No full textAcorns of Quercus pubescens (downy or pubescent oak) are typically collected in early
October (Fig. 11.41). For harvesting methods applicable to this oak species, readers
can refer to the guidelines provided for other oaks, such as Q. ilex, in this Compendium.
As recalcitrant seeds, Q. pubescens acorns are highly sensitive to desiccation, which
adversely affects their viability. To maintain viability from collection to sowing, the
moisture content of Q. pubescens acorns should not drop below 40%, with an optimal
range of 42%–48%
Early Post-Germination Physiological Traits of Oak Species Under Various Environmental Conditions in Oak Forests
No full textEarly post-germination physiological responses determine oak seedling establishment
success under changing environmental conditions. This study investigated four oak species
(Quercus cerris, Q. frainetto, Q. petraea, and Q. pubescens) through direct seeding experi-
ments across four locations in Serbia representing varying habitat conditions. Physiological
parameters (quantum yield of photosystem II, total stomatal conductance, and leaf va-
por pressure deficit) were measured intensively during the first growing season, along
with morphological traits and survival rates. Results revealed that microclimatic and soil
conditions exerted stronger effects on seedling physiology than species identity, with air
humidity, temperature, and soil moisture being primary drivers of photosynthetic per-
formance. Surviving seedlings exhibited 18% higher PhiPSII and 128% higher stomatal
conductance compared to non-survivors, demonstrating that physiological performance
is a reliable predictor of establishment success. Species-specific differences were evi-
dent. Q. cerris and Q. frainetto maintained the highest photosynthetic activity across sites,
Q. pubescens showed intermediate resilience, and Q. petraea displayed greater sensitivity to
environmental stress. These findings highlight the dominant role of microsite conditions in
shaping early seedling physiology and survival. Physiological measurements, particularly
PhiPSII and gtw, provide useful early indicators of establishment success during the first
growing season following direct seeding
Best practices for producing high quality seedlings and establishing main European tree species - Pinus sylvestris L.
No full textThe optimal period for Pinus sylvestris (Scots pine) cone harvesting is when seeds have
reached full maturity but before deterioration begins, typically in late summer to early
autumn, depending on local environmental conditions and site characteristics (Ivetić)
2023). Seeds collected in September show a germination rate of 95%–99.5% (Hurly
et al., 1987). Cones must be harvested before natural seed dispersal, which is influenced
by climatic factors, particularly by high temperatures that promote dispersal. For
example, in central Sweden, peak seed fall occurs in early to mid-May, suggesting
that seed collection should be completed before this period to prevent losses (Hannerz
et al., 2002). Temperature and relative air humidity, and the presence of seed predators
like squirrels, also influence the timing and method of harvesting.
P. sylvestris cones are usually harvested manually, a labor-intensive method that al-
lows, however, careful selection of cones (Roth, 2000). It involves climbing trees or us-
ing mobile elevators and several tools and devices to reach and cut the cones (Ivetić)
2023)
Biomarker fingerprint as a forensic tool for oil spill source identification in alluvial sediments
No full textOil pollutants are among the widespread contaminants in the world. Their content and composition is influenced by both, the content of the original crude oil or its derivative, and by the environmentalconditions at the location of their spillage. Although the environmental conditions can change significantly the content of oil pollutants, their biomarker fingerprint can remain intact and therefore can be used for the source identification.The aim of this study was application of saturated biomarkers for oil spill source identification in alluvial sediments. The investigated location is located in the alluvial plain of the Sava River, in the vicinity of the heating plant in New Belgrade, Serbia, and it is covering the surface area of 300 000 m2.Surface soil and sediment samples were collected at several microlocations from this locality. Fromthese samples extractable organic matter was isolated with dichloromethane using a Soxhlet apparatus. Saturated hydrocarbons were isolated from the extracts using a column chromatography and analyzed by GC-MS. The instrumental analysis included typical petroleum biomarkers: n-alkanes in the (m/z = 71), steranes (m/z = 217) and terpanes (m/z = 191). The analytical procedure employed was described in our previous papers.[1,2]The distribution of the n-alkanes revealed that most of the samples contained a mixture of an oilpollutant and a native organic matter. Their ratio varied depending on the distance from the heating plant, which was the only suspected source of oil pollution in this area. The analyses of steranes and terpanes showed that, at some locations, different oil pollutants were present. These results suggested that multiple discharges of the oil pollutants to the surrounding soil occurred over the years.According to these results it can be concluded that biomarker fingerprint can be a useful tool for oil spill identification and source discrimination in alluvial sediments
Sustainable Carbon Source from Almond Shell Waste: Synthesis, Characterization, and Electrochemical Properties
No full textThis study demonstrates the complete transformation of almond shell waste into a
high-performance carbon material for carbon paste electrode (CPE) fabrication. The biocarbon
was synthesized via carbonization at 800 ◦C and subsequently activated with CO2,
resulting in a semicrystalline structure rich in carbonyl groups—consistent with its lignocellulosic
origin (34.25% cellulose, 13.48% hemicellulose, 48.03% lignin). Carbonization
increased the total pore volume of carbonized almond (CAR_ALD) by nearly 13-fold
and the specific surface area by over two orders of magnitude compared to raw almond
(RAW_ALD), while CO2 activation further enhanced activated almond’s (ACT_ALD) surface
area (~19%) and pore volume (~35%). To improve electrochemical performance, Bi2O3
doped with Sm was applied as a surface modifier. Comprehensive characterization (N2
physisorption X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopic Analysis
(FTIR), X-Ray Photoelectron Spectroscopic Analysis (XPS), Thermogravimetric and Differential
Thermal Analysis (TG-DTA), Cyclic voltammetry (CV), Electrochemical impedance
spectroscopy (EIS)) confirmed the material’s structural integrity, graphitic features, and
successful modifier incorporation. Electrochemical testing revealed the highest current
response (48 μA) for the CPE fabricated from CAR_ALD/Bi2O3-Sm, indicating superior
electrocatalytic activity and reduced charge transfer resistance. Notably, this is the first
report of a fully functional CPE working electrode fabricated entirely from waste material
Drivers of seedling emergence and early growth of 12 European oak species: Results from a cross-continental experiment
No full textSeedling emergence constitutes a critical recruitment step, and early growth relates to plant competitive ability.
Understanding their drivers has implications for forestry and forest ecosystem conservation, restoration, and
adaptation to climate change. We seeded 6984 acorns in an experiment with 97 cases at 45 sites in 15 European
countries, encompassing 12 oak species. We tested whether the quality of the acorn batch, site-level weather and
soil characteristics, year of seeding, and species’ mean specific leaf area (SLA) affected the emergence and early
growth of seedlings after the first summer. Germination potential and acorn dry weight, measured under
controlled conditions, were positively associated with emergence and early growth. Seedling emergence was
negatively associated with the mean monthly temperature and cumulative winter precipitation, and it was higher
in the seedling cohort that was spared from the 2021 drought. Additionally, seedling emergence was positively
related to soil nutrient concentration and negatively to increasing soil pH, but not to water-holding capacity, and
growth was unrelated to soils. Species-level SLA was not related to either response. The four main study species
–Quercus cerris, Q. ilex, Q. petraea, and Q. robur– responded similarly to weather but not to soil conditions. We
conclude that, at a continental scale, and assuming that species establish within their current distributions, (a)
oak seedling emergence and early growth are associated with acorn quality rather than species identity or SLA,
(b) they are highest at sites with low winter precipitation and temperature, (c) emergence is reduced in dry years,
and d) soil properties play a secondary role at this early recruitment stage
Assessment and monitoring of early tree planting success
No full textIt cannot be overstated that any assessment of the growth and developmental trend of a
certain tree species must be grounded on a good understanding of its optimal growth
potential under favorable environmental conditions at the planting site. This enables
monitoring to prompt management to adopt supporting measures (termed adaptive
measures) when the observed trends diverge from the potential ones (Nichols and Williams, 2006; Le et al., 2012; Hutto and Kowalski, 2006; Susskind et al., 2012). Efficient
monitoring thus provides essential experience and knowledge for scaling up or planning
future planting initiatives (Kanowski et al., 2010; Derh�e et al., 2016; Guariguata and
Evans, 2020). Monitoring also generates information that contributes to transparency
and accountability (Benayas et al., 2009) and comprehensive reporting to investors on
performance.
From these considerations, it is evident that monitoring should be integrated in planning and implementation of tree planting interventions (Field et al., 2007; Lindenmayer
and Likens, 2010a, 2010b; McDonald-Madden et al., 2010; Susskind et al., 2012).
Moreover, it is crucial to define the scope of monitoring (McDonald–Madden et al.,
2010), as this may require different methodological approaches, intensity, and equipment (Hutto and Belote, 2013).
Timing is another aspect of monitoring. Early monitoring (during the initial phases
of tree growth and development) allows for the investigation of the correlation among
intrinsic factors (i.e., genetics) and extrinsic factors (i.e., environmental) that regulate the
growth and development pattern of the tree species under examination. Monitoring
planting performance and investigating the biological aspects of tree species’ life cycles
are not mutually exclusive (Geupel et al., 2011), but rather synergistic processes.
They both contribute to selecting tree species capable of exhibiting their optimal growth
and development on specific types of sites
Quality matters. A quantitative review on the effect of seedling morphology and nursery practices on the outplanting performance of forest plantings
No full textMost forest plantings worldwide are performed through the establishment of seedlings
grown in nurseries. During nursery cultivation, seedlings are exposed to several environmental conditions, such as temperature and growing media pH, and are supplied with
resources such as water, light, and mineral nutrients for optimal growth (Duryea,1984; Landis et al., 1989). Plants acclimate to these varied nursery conditions by adjusting morphological and physiological characteristics, leading to distinct phenotypes with
specific morphological and physiological traits. Once outplanted, these morphological
and physiological traits, referred to as functional attributes, determine seedling water,
carbon, and mineral nutrient economy, as well as their resistance and resilience to stress,
and consequent ability to establish and grow (Cuesta et al., 2010b; Grossnickle, 2012;
Grossnickle and MacDonald, 2018a, 2018b; Villar-Salvador et al., 2012). For instance,
leaf nitrogen concentration is often directly related to photosynthesis rate, which in turn
drives new organ growth and carbon storage (Uscola et al., 2015; Villar-Salvador et al.,
2015). Similarly, large 1 + 0 (i.e., 1-year–old), high nutrient content Pinus canariensis
seedlings showed 35% higher survival and twofold growth on a semiarid field site
compared to small 1 + 0 seedlings with little nutrient content (Luis et al., 2009). The
main cultivation practices that made the difference between the P. canariensis
stocktypes were the fertilization rate and the type of growing medium. In summary,
seedling growers have tools to shape key functional attributes that drive seedling
survival and growth in forest planting