Anatomski in ekofiziološki odzivi puhastega hrasta (Quercus pubescens Willd.) na vsebnost vode v tleh v submediteranskem fitogeografskem območju Slovenije

Intra-annual variations in leaf development, radial growth (including the secondary phloem part), sap flow and non-structural carbohydrates (NSCs) have been rarely studied in deciduous trees from drought-prone environments. In order to better understand the chronological order and temporal course of these processes, we monitored leaf phenology, xylem and phloem formation (in different tree parts), sap flow (HRM method), variations in NSC amounts and relationship between various wood-anatomical parameters and climatic factors in Quercus pubescens Willd. from Podgorski Kras in Slovenia during study period 2014–2016. For this purpose two research areas (RA) were selected, where at RA2 two adjacent plots differing in bedrock and soil type (flysch with eutric cambisol, high water retention - Flimestone with rendzic leptosol, low water retention - L) were sampled. We found that initial earlywood vessels were fully lignified and ready for water transport before bud opening at the beginning of April. Buds started to open in the second half of April and full leaf unfolding occurred by the end of May. Sap flow was increasing contemporarily with leaf development and LAI values. In the initial three weeks of radial growth, phloem growth preceded that of xylem. Cambial cell production was one month longer at the stem base than in branches. In addition, the xylem ring was wider than the phloem ring in all three parts. The amount of NSCs significantly differed among the tissue parts and sampling dates but not between the plots. Starch amounts were the highest in xylem and the amounts of free sugars were highest in inner phloem + cambium. Trees on F were more buffered against drier hydroclimatic conditions due to a higher availability of soil water. In the period of severe drought, sap flow density in trees growing on L was decoupled from the changes of vapour pressure deficit, due to increased employment of water conservation strategies (decreases in stomatal conductance). This was further translated into stomatal limitation of photosynthesis and contributed to reduced radial stem growth that revealed smaller yearly xylem increments in L trees and anatomical acclimations of conductive tissues, supporting/preserving trees\u27 hydraulic function. Xylem ring width, early- and latewood widths, diameter, area and number of earlywood vessels were mainly related to temperature. Our study confirmed that the temporal sequence of leaf development and radial growth are not contemporary. Soil water availability substantially influenced secondary growth in the stem, whereas NSC amounts seemed to be less affected. It has been demonstrated that latewood width and earlywood vessel characteristics are promising wood-anatomical parameters containing complementary information on the impact of weather conditions on radial growth. We concluded that climate is not the only driver for radial growth of Q. pubescens at the selected locationssoil type with respect to water retention potential is also important environmental feature that needs to be considered in wood formation studies and growth models in the future.Medletna dinamika v razvoju listov, debelinski rasti (vključno z razvojem sekundarnega floema), ksilemskem toku vode in količinah nestrukturnih ogljikovih hidratov (NOH) je redko preučevana pri listavcih v okolju, ki je izpostavljeno suši. Z namenom boljšega razumevanja kronološkega zaporedja in časovnega poteka teh procesov smo spremljali fenologijo listov, nastanek ksilema in floema (v različnih delih drevesa), ksilemski tok vode (HRM metoda), razporeditev NOH in povezanost med različnimi lesno-anatomskimi parametri in podnebnimi dejavniki pri puhastem hrastu (Quercus pubescens Willd.) na Podgorskem Krasu (JZ Slovenija) v obdobju 2014-2016. V ta namen smo izbrali dva raziskovalna območja (RO), kjer smo na RO2 vzorčili dve bližnji ploskvi, ki sta se razlikovali v matični podlagi in tipu tal (evtrična rjava tla na flišu, visoko zadrževanje vode - Frendzina na apnencu, slaba sposobnost zadrževanja vode - L). Ugotovili smo, da so bile prve traheje v ranem lesu popolnoma lignificirane in pripravljene za transport vode pred odpiranjem brstov na začetku aprila. V drugi polovici aprila so se brsti začeli odpirati in polno olistanje dreves je nastopilo konec maja. Ksilemski tok vode je naraščal sočasno z razvojem listov in vrednostmi LAI. V prvih treh tednih debelinske rasti je rast floema potekala pred rastjo ksilema. Začetek in konec nastanka kambijevih celic sta bila sinhronizirana na obeh lokacijah v vejah, vendar sta bila različna v deblu (za mesec daljše). Ksilemski prirastek v deblu in v vejah je bil širši od floemskega prirastka. Količina NOH se je bistveno razlikovala med posameznimi tkivi in datumi vzorčenja, ne pa med ploskvama. Količina škroba je bila najvišja v ksilemu in količina topnih sladkorjev v notranjem floemu + kambiju. Hrasti na mokrem rastišču F so bili bolj zaščiteni pred sušnimi hidroklimatskimi razmerami. V obdobju močne suše, ksilemski tok vode v hrastih na L ni bil odvisen od sprememb v deficitu tlaka vodne pare, ampak je na njegovo dinamiko vplivala povečana uporaba strategij hrasta za ohranjanje vode, kot je zmanjšanje stomatalne prevodnosti. To je vplivalo na omejevanje fotosinteze in prispevalo k zmanjšanju debelinske rasti debla. Anatomske študije so pokazale manjše letne prirastke ksilema pri hrastih s ploskve L in anatomske aklimacije prevodnih tkiv, ki podpirajo/ohranjajo hidravlično funkcijo dreves. Končna širina branike, širina kasnega in ranega lesa ter premer, površina in število trahej ranega lesa so bili povezani predvsem s temperaturo. Potrdili smo, da časovno zaporedje razvoja listov in debelinske rasti ni usklajeno. Razpoložljivost vode v tleh je bistveno vplivala na sekundarno rast v deblu, medtem ko na količine NOH ni bilo zaznati vpliva. Ugotovili smo, da so širina kasnega lesa in značilnosti trahej ranega lesa primerni lesno-anatomski parametri, ki vsebujejo komplementarne informacije o vplivu vremenskih razmer na debelinsko rast. Potrdili smo, da podnebje ni edino, ki vpliva na debelinsko rast puhastega hrasta na izbranih lokacijah. Talni tip z vidika sposobnosti zadrževanja vode je tudi pomembna okoljska značilnost, ki jo je potrebno upoštevati pri preučevanju rasti in funkcionalnosti dreves v različnih okoljskih razmerah ter modelih debelinske rasti v prihodnosti

Strengths and difficulties of children with behavioral problems: parents\u27 perspective

Uvod: Starši otrok z vedenjskimi in drugimi težavami se pogosto soočajo s težavami otrok na področju čustvovanja, koncentracije, vedenja in shajanja z drugimi ljudmi. Velikokrat je težavno vedenje otrok povezano s hiperkinetično motnjo, vendar vsi otroci niso zanjo tudi diagnosticirani. Hiperkinetična motnja je ena najpogostejših razvojnih motenj. Glavni znaki in simptomi so hiperaktivnost, nepozornost in impulzivnost. Starševstvo takemu otroku je lahko izjemno naporno in nemalokrat povzroča številne spore med staršema in tudi med drugimi družinskimi člani. Namen: Ugotoviti prednostna in težavna vedenja otrok s hiperkinetično motnjo in ostalimi vedenjskimi težavami, doživljanje težav staršev teh otrok in identifikacija področij, ki otrokom in staršem povzročajo največ težav. Metode dela: Uporabljena je bila neeksperimentalna metoda dela. Uporabljen je bil vprašalnik o prednostih in težavah, ki se uporablja za zgodnje odkrivanje pozitivnih in težavnih področij vedenja pri otrocih in mladostnikih. Dobljeni rezultati so bili vrednoteni z novejšo štiri-stopenjsko kategorizacijo. Vzorec je predstavljalo 43 otrok, starih med 8 in 15 let, ki so se udeležili tabora za vedenjsko zahtevne otroke. Rezultati: Glede na podane ocene staršev so otroci pri točkovanju čustvenih težav dosegli 3,14 točk, kar predstavlja povprečen rezultat. Pri vedenjskih težavah so dosegli skupno 3,16 točk, kar predstavlja nekoliko povišan rezultat. Pri težavah povezanih s hiperaktivnostjo so dosegli 6,65 točk, kar predstavlja nekoliko povišan rezultat. Pri medvrstniških težavah so dosegli 4,02 točk, kar predstavlja visok rezultat. Pri točkovanju socialnega vedenja so dosegli 7,67 točk, kar predstavlja nekoliko znižan rezultat. Pri točkovanju težav vsakdanjega življenja so dosegli 3,58 točk, kar predstavlja zelo visok rezultat. Pri točkovanju skupnih težav so dosegli 17,14 točk, kar predstavlja visok rezultat. Razprava in zaključek: Težave, ki spremljajo vedenjske in druge težave prizadenejo otroke, starše in ostale družinske člane. Obremenjujejo jih na vseh področjih življenja. Medicinske sestre v patronažnem varstvu in službah za zdravstveno varstvo otrok in mladine se morajo znati približati otroku s hiperkinetično motnjo in njegovi družini, jih dobro spoznati in jim nuditi strokovno podporo, spodbudo in pohvalo. Hiperkinetični motnji in ostalim vedenjskim težavam bi morali posvečati več pozornosti že na sistematskih pregledih in na zdravstveno-vzgojnih aktivnostih.Introduction: Parents of children with behavioural and other issues are facing problems when handling their emotions, concentration, behaviour, and interacting with other people. The child’s behaviour is oftentimes related to hyperkinetic disorder, but not all children are diagnosed with it. Hyperkinetic disorder is one of the most common developmental issues. Its main signs and symptoms are hyperactivity, lack of attention, and impulsiveness. Purpose: To find out the priorities and difficulties of children with hyperkinetic disorder and other behavioural problems, the parental experience of their relatives, and which aspects are causing the most difficulties to both. Methods: The method used was non experimental. I used a survey about priorities and difficulties of the disorder, which is generally used as a method of early discovery of behavioural priorities and difficulties with children and youth. The obtained results were assessed using a newer, four-level categorization. The children sample size was 43, aged between eight and 15 years, all of whom attended youth camp for children with behaviour problems in summer 2019. Results: Based on the ratings given by parents, their children scored 3.14 on the emotional intelligence issues, which is an average score. For behavioural problems, the score was 3.16, which represents a slightly increased score. With issues related to hyperactivity, they scored 6.65, which represents a slightly increased score. With peer issues, they scored 4.02, which represents a high score. For social behaviour, they scored 7.67, which represents a slightly lower score. For everyday living, they scored 3.58, which represents a very high score. For group issues, they scored 17.14, which is also a high score. Discussion and conclusion: The problems that occur with hyperkinetic disorders and other behavioural problems affect children, parents, and other family members. They are burdened in all areas of life. Nurses in community health care and other services for child and youth health care must know how to gain the confidence of parents and children with Hyperactivity Disorders in order to offer them support, incentive and praise. Greater attention during regular health check-ups and health education activities would enhance the quality of life for these children

Calibration of TCCON column-averaged CO2: the first aircraft campaign over European TCCON sites

The Total Carbon Column Observing Network (TCCON) is a ground-based network of Fourier Transform Spectrometer (FTS) sites around the globe, where the column abundances of CO2, CH4, N2O, CO and O2 are measured. CO2 is constrained with a precision better than 0.25% (1-σ). To achieve a similarly high accuracy, calibration to World Meteorological Organization (WMO) standards is required. This paper introduces the first aircraft calibration campaign of five European TCCON sites and a mobile FTS instrument. A series of WMO standards in-situ profiles were obtained over European TCCON sites via aircraft and compared with retrievals of CO2 column amounts from the TCCON instruments. The results of the campaign show that the FTS measurements are consistently biased 1.1% ± 0.2% low with respect to WMO standards, in agreement with previous TCCON calibration campaigns. The standard a priori profile for the TCCON FTS retrievals is shown to not add a bias. The same calibration factor is generated using aircraft profiles as a priori and with the TCCON standard a priori. With a calibration to WMO standards, the highly precise TCCON CO2 measurements of total column concentrations provide a suitable database for the calibration and validation of nadir-viewing satellite

Impact of weather conditions on wood-anatomical features in Pubescent Oak at Podgorski Kras

V okviru raziskave smo se osredotočili na vpliv vremenskih dejavnikov na lesno-anatomske značilnosti puhastega hrasta (Quercus pubescens Willd.), ki je ena od dominantnih domorodnih drevesnih vrst v slovenskem Submediteranu. V obdobju 2009%2014 smo raziskali povezave med različnimi lesno-anatomskimi parametri (končna širina branike, širina kasnega in ranega lesa ter premer, površina in število trahej ranega lesa) in vremenskimi dejavniki (padavine, temperatura in vsebnost vode v tleh). Zanimal nas je tudi potencial izbranih lesno-anatomskih parametrov ter komplementarnost oziroma enakovrednost le-teh za proučevanje podnebja na Podgorskem krasu. Preliminarni rezultati so pokazali, da so bili anatomski parametri povezani predvsem s temperaturo. Širina ranega lesa in površina trahej ranega lesa sta bili pozitivno povezani z maksimalno temperaturo, število trahej v ranem lesu in širina lesne branike pa pozitivno povezana s povprečno temperaturo v obdobju pred in na začetku kambijeve aktivnosti (januar%maj). To nakazuje, da vremenske razmere v navedenem obdobju pomembno vplivajo na hidravlične lastnosti ksilema. Pri širini kasnega lesa smo ugotovili največ povezav s temperaturo v poletnih mesecih, pri trahejah ranega lesa pa s temperaturo v obdobju januar%april. Vpliva padavin na razvoj ksilemske branike z našimi rezultati nismo potrdili. Ugotovili smo, da so širina kasnega lesa in značilnosti trahej ranega lesa primerni lesno-anatomski parametri, ki vsebujejo komplementarne informacije o vplivu vremenskih razmer na debelinsko rast puhastega hrasta. Poudariti je treba, da so bile naše analize opravljene v razmeroma kratkem časovnem obdobju in da bi bile za natančnejše rastno-podnebne zveze potrebne dodatne dolgoletne študije.Our research focused on the influence of climatic factors on wood-anatomical features of pubescent oak (Quercus pubescens Willd.), which is one of the dominant native tree species in Slovenian sub-Mediterranean climate. In the period 2009%2014 we studied relationship between various wood-anatomical parameters (xylem ring width, early- and latewood widths, diameter, area and number of earlywood vessels) and climatic factors (precipitation, temperature and soil water content). In addition, we checked whether the studied wood-anatomical parameters contained complementarity or redundant climatic information in pubescent oak at Podgorski Kras. Preliminary results showed that studied parameters were mainly related to temperature. In period before and at the onset of cambial activity (i.e. January%May), earlywood width and earlywood vessel area were positively related to the maximum temperature, whereas number of earlywood vessels and xylem ring width were positively related to the mean temperature. This indicates that weather conditions in this period have a significant impact on hydraulic properties of xylem. For latewood width, we found significant correlation with temperature in summer months and for earlywood vessels with the temperature in period January%April. We could not confirm the impact of precipitation on xylem ring development. We concluded that latewood width and earlywood vessel characteristics are promising wood-anatomical parameters containing complementary information on the impact of weather conditions on radial growth of pubescent oak. However, it is necessary to emphasize that our analysis has been performed in a relatively short time period, therefore long-term data are needed for more reliable assessment of the applicability of the selected wood-anatomical parameters to dendroclimatological studies

Post-fire effects on development of leaves and secondary vascular tissues in Quercus pubescens

An increased frequency of fire events on the Slovenian Karst is in line with future climate-change scenarios for drought-prone environments worldwide. It is therefore of the utmost importance to better understand tree-fire-climate interactions for predicting the impact of changing environment on tree functioning. To this purpose, we studied the post-fire effects on leaf development, leaf carbon isotope composition (%13C), radial growth patterns and the xylem and phloem anatomy in undamaged (H-trees) and fire-damaged trees (F-trees) of Q. pubescens with good re-sprouting ability in spring 2017, the growing season after a rangeland fire in August 2016. We found that the fully developed canopy of F-trees reached only half of the LAI values measured in H-trees. Throughout the season, F-trees were characterised by higher water potential and stomatal conductivity and achieved higher photosynthetic rates compared to unburnt H-trees. The foliage of F-trees had more negative %13C values than those of H-trees. This reflects that F-trees less frequently meet stomatal limitations due to reduced transpirational area and more favourable leaf-to-root ratio. In addition, the growth of leaves in F-trees relied more on the recent photosynthates than on reserves due to the fire disturbed starch accumulation in the previous season. Cambial production stopped 3 weeks later in F-trees, resulting in 60% and 22% wider xylem and phloem increments, respectively. A novel approach by including phloem anatomy in the analyses revealed that fire caused changes in conduit dimensions in the early phloem but not in the earlywood. However, premature formation of the tyloses in the earlywood vessels of the youngest two xylem increments in F-trees implies that xylem hydraulic integrity was also affected by heat. Analyses of secondary tissues showed that although xylem and phloem tissues are interlinked changes in their transport systems due to heat damage are not necessarily coordinated

Climatic regulation of leaf and cambial phenology in Quercus pubescens : their interlinkage and impact on xylem and phloem conduits

Increased frequency and severity of stressful events affects the growth patterns and functioning of trees which adjust their phenology to given conditions. Here, we analysed environmental effects (temperature, precipitation, VPD and SWC) on the timing of leaf phenology, seasonal stem radial growth patterns, and xylem and phloem anatomy of Quercus pubescens in the sub-Mediterranean in the period 2014%2019, when various adverse weather events occurred, i.e. spring drought in 2015, summer fire in 2016 and summer drought in 2017. Results showed that the timings of leaf and cambium phenology do not occur simultaneously in Q. pubescens, reflecting different environmental and internal constraints. Although year-to-year variability in the timings of leaf and cambial phenology exists, their chronological sequence is fairly fixed. Different effects of weather conditions on different stages of leaf development in spring were observed. Common climatic drivers (i.e., negative effect of hot and dry summers and a positive effect of increasing moisture availability in winter and summer) were found to affect the widths of xylem and phloem increments with more pronounced effect on late formed parts. A legacy effect of the timing of leaf and cambial phenology of the previous growing season on the timing of phenology of the following spring was confirmed. Rarely available phloem data permitted a comprehensive insight into the interlinkage of the timing of cambium and leaf phenology and adjustment strategies of vascular tissues in Mediterranean pubescent oak to various environmental constraints, including frequent extreme events (drought, fire). Our results suggest that predicted changes in autumn/winter and spring climatic conditions for this area could affect the timings of leaf and stem cambial phenology of Q. pubescens in the coming years, which would affect stem xylem and phloem structure and hydraulic properties, and ultimately its performance

Effect of soil water availability on intra-annual xylem and phloem formation and non-structural carbohydrate pools in stem of Quercus pubescens

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