Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 5

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  altitudinal variation
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
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
|
2016
|
tom 64
|
nr 2
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

The effect and implication of human disturbances on altitudinal variation of non-structural carbohydrates in Kobresia pygmaea

100%
Zhao Z., Zhang Y., Chen T., Cui X., Wu Q., An L.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 09
Non-structural carbohydrates in plant organs can mirror the plant overall carbon supply status and balance and can also provide evidence for their health evaluation in the ecosystem. Non-structural carbohydrates in Kobresia pygmaea, one dominant herbaceous species on the Qinghai-Tibetan Plateau, were measured to investigate altitudinal variation in non-structural carbohydrate accumulations, as well as engineering disturbance on the stability of the alpine grassland ecosystem. An increasing trend with elevation in total soluble sugars, fructose, and sucrose was detected in the K. pygmaea growing in both undisturbed and disturbed sites. However, there were higher amounts and a more distinctly altitudinal trend of non-structural carbohydrates with a minor fluctuation in undisturbed sites compared to disturbed sites. In addition, the altitudinal trend of sucrose is similar to that in sucrose phosphate synthase and sucrose synthase activities, while it is opposite to that in neutral invertase and soluble acid invertase activities, suggesting that the sucrose accumulation was primarily related to its synthesis. These results revealed that human disturbance resulted in a reduced carbon supply and altered the balance of carbohydrate utilization in plants on the Qinghai-Tibetan Plateau.
3

The trade-off and altitudinal variation in seed weight-number in Sinopodophyllum hexandrum (Royle) Ying (Berberidaceae) populations from the Hengduan Mts

84%
Meng L.-H., Wang Y., Luo J., Yang Y.-P., Duan Y.-W.
Polish Journal of Ecology
|
2014
|
tom 62
|
nr 3
Given the finite resources of seed production, a trade-off between seed weight and number was expected. However, it still remains unclear how the seed weight-number trade-off changes if there are some mechanisms to enhance resource acquirements during the fruit developments. Sinopodophyllum hexandrum presents furled leaves in flowering time but unfurled leaves in fruiting time, which is considered to enhance the photosynthates to fruit development. To determine the relationship between seed weight and number of S. hexandrum, we examined the altitudinal variations and the relationship between seed weight and number in the fruits from 27 populations of in 2009 and 2010. Our results showed that, along the altitudinal gradient, seed weight decreased significantly but seed number increased insignificantly, indicating that the selective pressure on seed production might come from seed dispersal in high altitude populations. There was no significant relationship between seed weight and number in most populations, but an inverse relationship was found between seed weight and number when the data from all populations were pooled, indicating the seed weight-number trade-off and resource limitation of seed production in S. hexandrum on species level. We suggested that the two unfurled leaves of S. hexandrum might contribute to the resources allocated to the fruit development via enhancing photosynthates, which might mask the seed weight-number trade-off on population level to some degree.
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The growth and biodiversity of spruce stands in variable climate conditions - Radziejowa case study

84%
Grodzki W., Ambrozy S., Gil W.
Folia Forestalia Polonica. Series A . Forestry
|
2013
|
tom 55
|
nr 3
In the experiment eight populations of Picea abies were chosen at 100 m intervals between 500 m and 1200 m altitude a.s.l.. In each population wood core samples were collected from 14–19 trees (126 cores total), and measured using a Corim Maxi device. At four of the eight sites (every 200 m in elevation between 500 m and 1100 m a.s.l.), the diversity of ground vegetation was evaluated, and temperature was recorded at every 100 m of altitude. The highest average radial increment of spruce occurred between the altitudes 800–1000 m a.s.l., which is probably the optimum for spruce. The larger increment indices observed at higher altitudes may signify a high growth potential of spruce. It may also suggest a recent upward shift of the optimum growth zone for this tree species. In 15 phytosociological records, the presence of 148 plant species forming plant associations: Dentario glandulosae- Fagetum typicum (sub-mountainous and mountainous form) and Abieti-Piceetum, and community Abies alba-Rubus hirtus, was documented. No relationship was found between ground vegetation species diversity (expressed by Shannon-Wiener index) and levels of stand diversity. The vegetation species diversity varied with the elevation above sea level: the highest plant diversity was found at 500 m a.s.l., and decreased with increasing altitude. The potential increase in air temperatures may result in changes to the altitudinal range of many plant species including trees, and consequently in an upward shift of the boundaries of plant zones; in this case the sub-mountainous and lower mountainous forest zone. In this region, the optimal zone for Norway spruce may be restricted to the highest elevations.
5

Altitudinal variation in the diet of sika deer on the Izu Peninsula: patterns in the transitional zone of geographic variation along the Japanese archipelago

67%
Kitamura T., Sato Y., Takatsuki S.
Acta Theriologica
|
2010
|
tom 55
|
nr 1
89-93
Geographical variation in the diet of sika deer Cervus nippon Temminck, 1838 has been well characterised: northern populations are grazers, whereas southern deer are browsers. This variation largely reflects genetic-based differences in morphology. However, environmental factors would be also important. If a same genetic population live in different habitats, we can check altitudinal shifts in sika deer food consumption. We hypothesised that changes in the diet of the sika deer population on the Izu Peninsula, which is located within the transitional zone of resource (vegetation) variation and encompasses a broad altitudinal range, would mirror shifts in the composition of vegetation. Analyses of the rumen contents of the deer population indicated that dwarf bamboo accounted for 10.5, 46.2, and 74.3% of the deer diet in the low (<800 m), middle (800–1000 m), and high (>1000 m) altitudinal zones, respectively. In contrast, evergreen broad-leaved species accounted for 35.7, 23.1, and 5.9%, respectively. These results suggest that the diet of sika deer is more strongly affected by environmental factors, such as plant community composition, than by genetic factors.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.