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1

Altitude patterns of leaf carbon isotope composition in a subtropical monsoon forest

100%
Pan S., Zhang W., Zhao M., Li Y., Xu S., Wang G.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 4
Leaf carbon isotope composition (δ¹³C) of both vascular and non-vascular plants were investigated in order to assess their variability along an altitude gradient (414, 620, 850, 1086, 1286 and 1462 m) from a subtropical monsoon forest located at Mt. Tianmu Reserve, eastern China. Leaf δ¹³C values of all plant species ranged from -34.4 to -26.6‰, with an average of -29.8‰. There is no significant difference in leaf δ¹³C between vascular plants and mosses, however, trees had significantly higher δ¹³C values than herbs. For pooled data, leaf δ¹³C was positively correlated with altitude. Leaf δ¹³C was significantly and negatively correlated with annual mean temperature and atmospheric pressure, while it was significantly and positively correlated with soil water content. Furthermore, there was no relationship between leaf δ¹³C and soil nitrogen content or soil phosphorus content. The altitudinal trend in leaf δ¹³C is the consequence of the interaction between temperature, atmospheric pressure and soil water content.
2

Ecological adaptation of the seed microsculptures of Saussurea from different altitudes (Qinghai-Tibet Plateau)

100%
Li Z., Du G.
Polish Journal of Ecology
|
2015
|
tom 63
|
nr 4
The aim of this study was to explore ecological adaptation of seed microsculptures of Saussurea from different altitudes. Scanning electron microscopy was used to observe the cypselae surface of 10 taxa of Saussurea collected from the eastern edge of Qinghai-Tibet plateau, China. The results indicated that the microsculptures had clear and consistent variations in some samples collected from high (4200 m a.s.l.) and low-altitude sites (2200 m a.s.l.). The thickness of stripes and distance between stripes are increasing while sulcus depth is increasing from a low to a high altitude (P < 0.01). The seed-coat surface was becoming rougher from low to high altitude. The surviving rate of seeds was lower at high altitude than that at low altitude in all the species. The surviving rate of the seeds collected from the high altitudes was higher than that of the seeds collected from low altitudes when sown at the same altitude. All the results suggested that there is selection pressure of the altitude on the development of the microsculpture patterns, which increases absorbed sunlight, the residence time of soil water and nutrition. The changes can make the seeds survive better at extreme environments (cold and dry). The cypselae microsculpture patterns should be used as potential adaptation biomarkers for the species of Saussurea from low- to high-altitude.
3

Different patterns of changes in foliar carbon isotope composition along altitude

100%
He Z., Zhan S., Wang W., Hu L., Wu S.
Polish Journal of Ecology
|
2017
|
tom 65
|
nr 2
Three types of alpine plant species,Carex montis-everestii,Quercus aquifolioidesandStipa capillacea, along an altitudinal gradient of 3005–5025 m on the Tibetan Plateau, were chosen to test the generality of the hypothesis that foliar carbon isotope composition (δ¹³C) of C3 plants increases significantly with altitude and to determine climate drivers shaping its altitudinal pattern. Temperature and relative humidity showed significantly negative correlations with altitude; however, precipitation and soil water potential remained unchanged with altitude. Foliar δ¹³C of C. montis-everestii,Q. aquifolioides,S. capillaceaalone or combined together did not significantly increase with altitude, which does not support the leading hypothesis of increased foliar δ¹³C with altitude. There was no difference in foliar δ¹³C among all three species. Multi-factor correlation analyses showed that temperature, precipitation and relative humidity alone did not affect foliar δ¹³C ofC. montis-everestiiandS. capillacea, but conferred significant effects on foliar δ¹³C of Q. aquifolioides.
4
Content available remote

Non-invasive measurement of circulation time using pulse oximetry during breath holding in chronic hypoxia

100%
Zubieta-Calleja G. R., Zubieta-Castillo G., Paulev P.-E., Zubieta-Calleja L.
Journal of Physiology and Pharmacology. Supplement
|
2005
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tom 56
|
nr 4
251-256
Pulse oximetry during breath-holding (BH) in normal residents at high altitude (3510 m) shows a typical graph pattern. Following a deep inspiration to total lung capacity (TLC) and subsequent breath-holding, a fall in oxyhemoglobin saturation (SaO2) is observed after 16 s. The down-pointed peak in SaO2 corresponds to the blood circulation time from the alveoli to the finger where the pulse oximeter probe is placed. This simple maneuver corroborates the measurement of circulation time by other methods. This phenomenon is even observed when the subject breathes 88% oxygen (PIO2 = 403 mmHg for a barometric pressure of 495 mmHg). BH time is, as expected, prolonged under these circumstances. Thus the time delay of blood circulation from pulmonary alveoli to a finger is measured non-invasively. In the present study we used this method to compare the circulation time in 20 healthy male high altitude residents (Group N with a mean hematocrit of 50%) and 17 chronic mountain sickness patients (Group CMS with a mean hematocrit of 69%). In the two study groups, the mean circulation time amounted to 15.94 ±2.57 s (SD) and to 15.66 ±2.74 s, respectively. The minimal difference was not significant. We conclude that the CMS patients adapted their oxygen transport rate to the rise in hematocrit and blood viscosity.
5
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Variations in the physical properties of surf generated aerosols with altitude

100%
Zielinski T.
Oceanologia
|
2003
|
tom 45
|
nr 4
Vertical profiles of marine aerosol size distribution and concentration in the marine boundary layer over surf zones depend strongly on wind speed, direction and duration as well as the sea bottom profile. The measurements in the present study were carried out in various seasons of the year with all these factors being taken into consideration. The data with respect to offshore winds were neglected in the calculations, since in such cases the major aerosol contribution was from terrigenous and anthropogenic particles. It was confirmed that in the range of wind speeds from 1 m s−1 to 12 m s−1 there were measurable differences in the concentrations, particularly in the size distribution of marine aerosol particles at two stations differing with respect to their sea bottom profiles.
6

Life span of needles of Pinus mugo Turra: effect of altitude and species origin

84%
Boratynski A., Jasinska A., Boratynska K., Iszkulo G., Piorkowska M.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 3
567-572
The needle life span of evergreen coniferous trees is a species-specific trait but can be also affected and modified by environmental conditions. On the basis of field observations of needle life span during three periods in two populations of Pinus mugo in the Tatra Mts (altitude: 1600–1700 m) and Sudety Mts (altitude 830–1420 m), 11 populations from various altitudes we concluded that: 1) within the same population needle life span remained the same over the three periods of observations, 2) needle life span in the Tatra Mts is about 1 year longer than in the Sudety Mts, ranging from 5.5 to 5.9 years and 3) needle life span in the Sudety Mts increases significantly with the altitude of the population. The longer life span of needles in the Tatra Mts may be specific for the population, i.e. it may be due to a different population origin (another Pleistocene centre of the species), and the shorter life span of needles noted in the Sudety Mts may be due to higher soil pollution in this region.
7

Cone entomofauna of Norway spruce Picea abies (L.) Karst. in selected stands of the Tatra National Park in Poland

84%
Koziol M.
Electronic Journal of Polish Agricultural Universities. Series: Forestry
|
2007
|
tom 10
|
nr 4
8

Changes in caffeine content during fruit development in Coffea canephora P. ex. Fr. grown at different elevations

84%
Sridevi V., Giridhar P.
Journal of Biology and Earth Sciences
|
2014
|
tom 04
|
nr 2
9

Changes of aerosol concentration with altitude in the marine boundary layer in coastal areas of the Southern Baltic Sea

84%
Zielinski T.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1998
|
tom 46
|
nr 3-4
10

Altitudinal trends in needle chlorophyll content and chlorophyll fluorescence of Norway spruce [Picea abies Karst.] seedlings exposed to increased ultraviolet-B radiation

84%
Robakowski P., Modrzynski J.
Polish Journal of Ecology
|
2000
|
tom 48
|
nr 1
11

Altitudinal variability of the soil water content in natural and managed beech [Fagus sylvatica L.] forests

67%
Pichler V., Durkovic J., Capuliak J., Pichlerova M.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 2
313-319
European beech (Fagus sylvatica L.) ranks as one of the most adaptive species among European indigenous trees. Variable interactions between the trees and soil water depend on both phenotypic plasticity of the species and natural conditions. They are controlled through stomatal regulation and the ability of beech trees to accelerate quickly their growth if available resources increase. However, the effect of forest density at various altitudes on the soil water content in beech stands has been studied rather scarcely. Therefore, we monitored soil moisture by means of Time Domain Reflectometry in series of natural and managed stands located on sites representing the lower altitude (200–550 m a.s.l.), middle altitude (550–1050 m a.s.l.) and higher altitude (1050–1300 m a.s.l.) zones of the natural beech belt in the Western Carpathians, Slovakia. Forest stand density, expressed in terms of basal area, i.e. the sum of cross section areas of the tree stems at 1.30 m height, was unchanged in natural stands, but it was reduced by 60% in the shelterwood stands. In the clear-cuts, all trees were removed. Total soil water content (SWC) under forest stands was calculated in mm as the product of soil moisture and soil depth, the latter acquired by electrical resistivity tomography. SWC differences between natural and shelterwood stands of the lower altitude, middle altitude and higher altitude zones averaged 18 mm, 36 mm and –3 mm, respectively. According to the Friedman test on ranks, followed by post-hoc multiple comparison testing, the difference was only significant within the middle altitude zone. In it, soil water consumption by the natural stand was limited only by the hormonally controlled seasonal regulation. The comparatively low water loss in the shelterwood stand resulted from a small rainfall interception by forest canopy and a decreased soil water uptake due to reduced basal area, leaf area index and simple age-size forest structure. In the lower altitude zone, the precipitation deficit and limited extractability of soil water were responsible for the absence of larger SWC differences. As opposed to that, low potential evapotranspiration prevented any noticeable SWC differences within the higher altitude zone.
12

Seed mass increase along altitude within four Saussurea (Asteraceae) species in Tibetan Plateau

67%
Wu G.-L., Tian F.-P., Ren G.-H., Liu Z.-H.
Polish Journal of Ecology
|
2011
|
tom 59
|
nr 3
Seed mass is a critical lifehistory character in seed evolutionary ecology. Plant species can present responses in seed mass to environment stresses. We tested the hypotheses that seed mass was positively correlated with altitude within species. We selected four congeneric Saussurea species as study objects, and collected their seeds along altitudinal gradients (2100–4200 m a.s.l.) in the alpine area of the Qinghai-Tibetan Plateau, China. Results showed that mean seed mass of the four species were significantly affected by altitude (P <0.001). There was a general trend of an increase in seed weight with altitude among the populations of the four species. In addition, mean seed mass of four species were not significantly different, but all presented a bigger coefficients of variation within species along altitude gradients. Our results indicate selection pressure within species, with larger seeds occurring at higher altitudes.
13

The influence of forest density index and altitude on selected features of the bilberry (Vaccinium myrtillus L.) base in mountain stands

67%
Barszcz A., Karpierz M.
Electronic Journal of Polish Agricultural Universities. Series: Forestry
|
2001
|
tom 04
|
nr 2
14

Micro- and macroscale changes in density and diversity of testate amoebae of tropical montane rain forests of Southern Ecuador

67%
Krashevska V., Maraun M., Scheu S.
Acta Protozoologica
|
2010
|
tom 49
|
nr 1
17-28
15

Species composition and abundance of the oribatid fauna (Acari, Oribatida) at two lakes in the Floyen area, Bergen, Norway

67%
Seniczak A., Solhoy T., Seniczak S., De La Riva-Caballero A.
Biological Letters
|
2010
|
tom 47
|
nr 1
16

Millipede [Diplopoda] communities in mixed oak-hornbeam forest stands - effect of selected site factors

67%
Stasiov S.
Polish Journal of Ecology
|
2009
|
tom 57
|
nr 4
785-792
The influence of the site factors related to soil, forest stand and litter as well as to altitude, exposure and slope - on the composition/abundance structure of millipede communities (Diplopoda) was estimated. The research was carried out in 1999 to 2002 in 13 mixed oakhornbeam forest stands in Malé Karpaty Mts. (South-Western Slovakia) ranged from 132 to 768 m a.s.l. In each locality, millipedes were collected by sieving of the litter taken at monthly intervals from 16 quadrates (25  25 cm) in each site. The redundancy analysis was applied. The most apparent influence on the community structure was ascertained for pH-value of litter and age of forest stand. Nitrogen content in litter was the most important factor, influencing the species richness of the millipede assemblages in studied sites.
17

Boundary between submontane and lower montane zones in the 'Huculskie' forest reserve [Bieszczady Mts, Eastern Carpathians]

67%
Michalik S.
Roczniki Bieszczadzkie
|
2003
|
tom 11
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