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1.
Ecology of the pteridophytes on the southern slopes of Mt. Kilimanjaro – I. Altitudinal distribution
140 taxa of 61 genera in 24 families of pteridophytes were recorded on the southern slopes of Mt. Kilimanjaro. These represent about one third of the entire pteridophyte flora of Tanzania. The families richest in species are the Aspleniaceae, the Adiantaceae, the Dryopteridaceae, the Thelypteridaceae and the Hymenophyllaceae. Due to its luxuriant montane rain forest, which receives a precipitation of up to over 3000 mm, Mt. Kilimanjaro is distinctly richer in pteridophyte species than other volcanoes in East Africa. However, compared with the mountains of the Eastern Arc, the number of pteridophytes on Mt. Kilimanjaro is smaller. This can be explained by the widely destroyed submontane (intermediate) forest rather than by the higher age of the Eastern Arc Mts.The altitudinal distribution of all ferns was investigated in 24 transects. On the southern slopes of Mt. Kilimanjaro they were found in an altitudinal range of 3640 m. Cyclosorus quadrangularis, Azolla nilotica, Azolla africana andMarsilea minuta are restricted to the foothills, while Polystichum wilsonii, Cystopteris nivalis and Asplenium adiantum-nigrum are species found in the highest altitudes.Based on unidimensionally constrained clustering and on the analysis of the lowermost and uppermost occurrence of species, floristic discontinuities within the transects were determined. From these data and from an evaluation of the distribution of ecological groups and life forms, 11 altitudinal zones could be distinguished: a colline zone (–900 m asl), a submontane zone (900–1600 m asl) with lower and upper subzones, a montane zone (1600-2800 m asl) divided into 4 subzones, a subalpine zone (2800–3900 m asl) with lower, middle and upper subzones, and finally a (lower) alpine zone above 3900 m. The highest species numbers were observed in the lower montane forest belt between 1600 and 2000 m altitude. The zonation of ferns found at Mt. Kilimanjaro corresponds well with the vegetational zonation described by other authors using bryophytes as indicators in different parts of the humid tropics. 相似文献
2.
Liang-Jun Da Min-Ming Kang Kun Song Kan-Kan Shang Yong-Chuan Yang Ai-Mei Xia Yu-Feng Qi 《Ecological Research》2009,24(6):1287-1299
Much of the primary vegetation at low altitudes has been greatly altered or destroyed by a long history of human activities.
This is particularly true in eastern China, where low-altitude areas are now dominated by secondary forests or plantations.
Altitudinal vegetation zonation of this region is often based on these secondary forests, resulting in seral vegetation with
an obscure zonal sequence. Here, we deduced the potential climax vegetation according to the regeneration patterns of the
dominant species of the secondary forests at low altitudes (below 1,000 m a.s.l.) on Mt. Tianmu (1,506 m a.s.l., 30°18′30″–30°21′37″N,
119°24′11″–119°27′11″E). Based on the potential climax vegetation combined with the floristic composition and community structure,
three vegetation zones were identified, viz: (1) evergreen broad-leaved forest zone (400–950 m a.s.l.); (2) evergreen and
deciduous broad-leaved mixed forest zone (950–1,100 m a.s.l.); (3) deciduous broad-leaved forest zone (1,100–1,506 m a.s.l.).
The altitudinal vegetation zones identified in this study correspond with the thermal conditions on Mt. Tianmu. The distribution
of vegetation on Mt. Tianmu was limited by lower temperatures in winter, and the altitudinal thermal vegetation zones on this
mountain were more similar to the thermal vegetation of Japan than to that of China. The vertical distributions and roles
of conifers were different between the eastern and the western regions along 30°N latitude in humid East Asia. Cryptomeria fortunei formed the emergent layer, towering above the broad-leaved canopy at middle altitudes as C. japonica on Yakushima, but disappeared at high altitudes with hydrothermal limitation on Mt. Tianmu. 相似文献
3.
Altitudinal changes in carbon storage of temperate forests on Mt Changbai, Northeast China 总被引:8,自引:0,他引:8
Biao Zhu Xiangping Wang Jingyun Fang Shilong Piao Haihua Shen Shuqing Zhao Changhui Peng 《Journal of plant research》2010,123(4):439-452
A number of studies have investigated regional and continental scale patterns of carbon (C) stocks in forest ecosystems; however,
the altitudinal changes in C storage in different components (vegetation, detritus, and soil) of forest ecosystems remain
poorly understood. In this study, we measured C stocks of vegetation, detritus, and soil of 22 forest plots along an altitudinal
gradient of 700–2,000 m to quantify altitudinal changes in carbon storage of major forest ecosystems (Pinus koraiensis and broadleaf mixed forest, 700–1,100 m; Picea and Abies forest, 1,100–1,800 m; and Betula ermanii forest, 1,800–2,000 m) on Mt Changbai, Northeast China. Total ecosystem C density (carbon stock per hectare) averaged 237 t C ha−1 (ranging from 112 to 338 t C ha−1) across all the forest stands, of which 153 t C ha−1 (52–245 t C ha−1) was stored in vegetation biomass, 14 t C ha−1 (2.2–48 t C ha−1) in forest detritus (including standing dead trees, fallen trees, and floor material), and 70 t C ha−1 (35–113 t C ha−1) in soil organic matter (1-m depth). Among all the forest types, the lowest vegetation and total C density but the highest
soil organic carbon (SOC) density occurred in Betula ermanii forest, whereas the highest detritus C density was observed in Picea and Abies forest. The C density of the three ecosystem components showed distinct altitudinal patterns: with increasing altitude, vegetation
C density decreased significantly, detritus C density first increased and then decreased, and SOC density exhibited increasing
but insignificant trends. The allocation of total ecosystem C to each component exhibited similar but more significant trends
along the altitudinal gradient. Our results suggest that carbon storage and partitioning among different components in temperate
forests on Mt Changbai vary greatly with forest type and altitude. 相似文献
4.
The decrease in temperature with increasing elevation may determine the altitudinal tree distribution in different ways: affecting survival through freezing temperatures, by a negative carbon balance produced by lower photosynthetic rates, or by limiting growth activity. Here we assessed the relative importance of these direct and indirect effects of altitudinal decrease in temperature in determining the treeline in central Chile (33°S) dominated by Kageneckia angustifolia. We selected two altitudes (2000 and 2200 m a.s.l.) along the treeline ecotone. At each elevation, leaf non-structural carbohydrates (NSC) and gas exchange parameters were measured on five individuals during the growing season. We also determined the cold resistance of K.␣angustifolia, by measuring temperatures that cause 50% seedling mortality (LT50) and ice nucleation (IN). No differences in net photosynthesis were found between altitudes. Although no differences were detected on NSC concentration on a dry matter basis between 2000 and 2200 m, when NSC concentration was expressed on a leaf area basis, higher contents were found at the higher elevation. Thus, carbon sink limitations may occur at the K. angustifolia’s upper altitudinal limit. For seedlings derived from seeds collected at the 2200 m, LT50 of cold-acclimated and non-acclimated plants were −9.5 and −7 °C, respectively. However, temperatures as low as −10 °C can frequently occur at this altitude during the end of winter. Therefore, low temperature injury of seedlings seems also be involved in the treeline formation in this species. Hence, a confluence of global (carbon sink limitation) and regional (freezing tolerance) mechanisms explains the treeline formation in the Mediterranean-type climate zone of central Chile. 相似文献
5.
Plant species diversity and endemism demonstrate a definite trend along altitude. We analyzed the (i) pattern of tree diversity
and its endemic subset (ii) frequency distribution of altitudinal range and (iii) upper & lower distributional limits of each
tree species along altitudinal gradients in eastern Himalaya. The study was conducted in Subansiri district of Arunachal Pradesh.
Data on the tree species (cbh ≥ 15 cm) were gathered every 200 m steps between 200 m and 2200 m gradients. Tree diversity
demonstrated a greater variation along the gradients. A total of 336 species (of which 26 are endemic) were recorded belonging
to 185 genera and 78 families. The alpha diversity demonstrated a decreasing pattern with two maxima (i.e., elevational peaks)
along the gradients; one in 601–1000 m and the other in 1601–1800 m, corresponding to transition zones between tropical-subtropical
and subtropical-temperate forests. Pattern diversity revealed a narrow range along the gradients. Frequency of altitudinal
range was distributed between 1 and 41. Only one species (Altingia excelsa) showed widest amplitude, occurring over the entire range. Highest level of species turnover was found in 400–600 m step
at lower elevational limit whereas for upper elevational limit, the highest turn over was recorded between 800 and 1000 m.
Tree diversity decreased and its endemic subset increased along the gradients. Two maximas in tree diversity pattern correspond
to forest transition zones with subtropical-temperate transition is narrower than tropical-subtropical. The pattern observed
here could be attributed to varied microclimates or environmental heterogeneity. If altitudinal amplitude of a species is
considered as an aspect of its niche breadth, it is clear from these results that niche breadth in these organisms is in fact
independent of the diversity of the assemblage in which they occur. This analysis calls for detailed floristic studies to
determine the breadth of changes between adjacent forest types and details of local species richness in high diversity areas. 相似文献
6.
Edith Huber Wolfgang Wanek Michael Gottfried Harald Pauli Peter Schweiger Stefan K. Arndt Karl Reiter Andreas Richter 《Plant and Soil》2007,301(1-2):65-76
We investigated the nitrogen (N) dynamics of an alpine–nival ecotone on Mt. Schrankogel, Tyrol, Austria, in relation to temperature.
Natural abundance of 15N was used as a tool to elucidate differences in N cycling along an altitudinal transect ranging from 2,906 to 3,079 m, corresponding
to a gradient in mean annual temperature of 2.4 °C. The amount of total soil N, of plant available N and soil C/N ratio decreased
significantly with increasing altitude, whereas soil pH increased. Soil δ
15N decreased with increasing altitude from +2.2 to −2.1‰ and δ
15N of plant tissues (roots and leaves) decreased from −3.7 to −5.5‰. The large shift in soil δ
15N of 4.3‰ from the lowest to the highest site suggested substantial differences in N cycling in alpine and nival ecosystems
in the alpine nival ecotone investigated. We concluded that N cycling at the alpine–nival ecotone is likely to be controlled
by various factors: temperature, soil age and development, atmospheric N deposition and plant competition. Our results furthermore
demonstrate that the alpine–nival ecotone may serve as a sensitive indicator of global change. 相似文献
7.
Altitudinal forest and climate changes from warm, dry valley bottom (1250 m a.s.l.) to cool, humid ridge top (3550 m a.s.l.) along the typical dry valley slopes of the Bhutan Himalaya were studied. Annual mean temperature decreased upslope with a lapse rate of 0.62 °C·100 m−1 from 18.2 °C at the valley bottom to 4.3 °C at the ridge top. On the contrary volumetric soil moisture content increased from 14.7 to 75.0%. This inverse relationship is the major determinant factor for the distribution of different forest types along the altitudinal gradient. Based on the quantitative vegetation data from 15 plots arranged ca. 200 m in altitude interval (1520–3370 m a.s.l.), a total of 83 tree species belonging to 35 families were recorded. Three major formation types of lower and upper coniferous forests, and a mid-altitude evergreen and deciduous broad-leaved forest were contrasted. Including two transitional types, five forest zones were categorized based on cluster analysis, and each zone can be characterized by the dominants and their phytogeographical traits, viz. (1) west Himalayan warm, dry pine (1520–1760 m a.s.l.), (2) wide ranging east-west Himalayan mixed broad-leaved (1860–2540 m a.s.l.), (3) humid east Himalayan evergreen broad-leaved (2640–2820 m a.s.l.), (4) cool, humid east Himalayan conifer (2950–3210 m a.s.l.), and (5) wide ranging cold, humid conifer (3305–3370 m a.s.l.). Structurally, total basal area (biomass) increased from 15.2 m2 ha−1 in the pine forest (1520 m) to 101.7 m2 ha−1, in the conifer forest (3370 m a.s.l.). Similarly, soil organic carbon increased from 2.7 to 11.3% and nitrogen from 0.2 to 1.9% indicating dry, poor nutrient fragile ecosystem at the dry valley bottom. We concluded that low soil moisture content (<20%) limits downslope extension of broad-leaved species below 1650 m a.s.l. while coldest month’s mean temperature of −1 °C restricted the upslope extension of evergreen broad-leaved species above 3000 m a.s.l. Along the dry valley slopes, the transition from dry pine forest in the valley bottom, to a mixture of dry west Himalayan evergreen and deciduous east Himalayan broad-leaved, and to humid evergreen oak–laurel forests feature a unique pattern of forest type distribution. 相似文献
8.
María Luz Zapata Basílico Graciela Pose Vanesa Ludemann Virginia E. Fernández Pinto Elena E. Aríngoli Alberto Ritieni Juan Carlos Basílico 《Mycotoxin Research》2010,26(2):85-91
The Fusarium diversity and the mycobiota associated with moldy wheat kernels from Santa Fe province, Argentine, was assessed. The wheat
cultivated area in Santa Fe province is divided according to agrometeorological conditions into two zones: Zone I (north-central)
and Zone II (south). The natural occurrence of Fusarium toxins BEA, FUP, DON and NIV was also determined. Cladosporium was the most abundant of the 19 genera identified, followed by Fusarium, Phoma and Alternaria. Zone II shows a predominance of F. graminearum and F. culmorum. In Zone I, DON was present in 13/32 samples (range 0.43–3.60 mg kg−1) and NIV in 6/32 samples (range 0.11–0.40 mg kg−1). In zone II, DON was found in 11/21 samples (range 0.57–9.50 mg kg−1) and NIV in 4/21 samples (range 0.10–0.60 mg kg−1). BEA and FP were not detected in both zones. 相似文献
9.
Jacot Katja A. Lüscher Andreas Nösberger Josef Hartwig Ueli A. 《Plant and Soil》2000,225(1-2):201-211
The significance of symbiotic N2 fixation in legumes (Trifolium alpinum L., T. nivale Sieber, T. pratense L., T. badium Schreber, T. thalii Vill., T. repens L., Lotus alpinus [DC.] Schleicher, L. corniculatus L., Vicia sativa L.) and other N sources for the N budget of grassland ecosystems was studied along an altitudinal gradient in the Swiss Alps.
The total annual symbiotic N2 fixation was compared with other sources of N for plant growth of the total plant community (mineralisation and wet deposition).
The contribution of symbiotically fixed N to total above-ground N yield of the swards decreased from at least 16% to 9% with
increasing altitude where legumes were present. This decrease was due to a decrease in the yield proportion of legumes from
15% at 900 and 1380 m a.s.l. to 5% at 2100 and 2300 m a.s.l. (no legumes were found above 2750 m a.s.l.) and not to a decline
in the activity of symbiotic N2 fixation. With increasing altitude legumes are more patchily distributed. The high symbiotic N2 fixation of individual plants up to their altitudinal limit is not primarily the result of low mineral N availability since
an addition of NH4
+ or NO3
− fertiliser at 2300 m a.s.l. led either to no decrease or only to a minor decrease in symbiotic N2 fixation. At 1380 m a.s.l., N mineralisation (13.45 g N m−2 yr−1) appeared to be the main source of N for growth of the sward; N from symbiosis (at least 1.0 g to 2.6 g N m−2 yr−1) and wet deposition (0.4 g to 0.6 g m−2 yr−1) was not a significant N source for plant growth at this altitude. At 2100 m a.s.l., the combined amounts of N from symbiotic
N2 fixation (at least 0.1 g N m−2 yr−1) and wet deposition (0.3 g N m−2 yr−1) appeared to be similarly important for plant growth as soil N mineralisation (0.47 g N m−2 yr−1). At high altitudes, wet N deposition and symbiotic N2 fixation together represent a significant source of N for the grassland ecosystem while at low altitudes these N inputs appear
to be much less important.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
Altitudinal zonation of evergreen, deciduous and coniferous forests on Mt. Emei (3099 m asl, 29°34.5' N, 103°21.5' E), Sichuan, China was studied to understand the transition of vegetation zonation from tropical to temperate mountains in humid Asia. On the basis of quantitative data on floristic composition and community structure sampled at ten plots selected in different altitudes on the eastern slope of the mountain, forest zonation and the inter-relationships among different life-forms of trees in each zonal forest community were studied quantitatively. Three forest zones were identified physiognomically along the altitudinal gradient, viz. (i) the evergreen broad-leaved forest zone (660–1500 m asl), (ii) the mixed forest zone (1500–2500 m asl), and (iii) the coniferous forest zone (2500–3099 m asl). Great compositional changes were observed along elevation, and the zonal forest communities were characterized by their dominants and floristic composition. Maximum tree height decreased from 33 m at lower middle altitude (965 m asl) to 13 m near the summit (2945 m asl). There was no apparent deciduous forest zone along the altitudinal gradient, but true mixed forests of three life-forms (evergreen, deciduous, and coniferous) were formed around 2000–2500 m asl. Patches of deciduous forest were found in a lower part of the mixed forest zone, particularly on scree slopes, between 1450 m and 1900 m asl. These patches were dominated by the Tertiary relic deciduous trees, such as Davidia involucrata, Tetracentron sinense, and Cercidiphyllum japonicum var. sinense. High species diversity in the mixed forest zone resulted from the overlapping of different life-forms at middle altitudes, which is partly due to wider variety of temperature-altitude correlations. A comparison of the altitudinal zonation with the other east Asian mountain vegetation clarified that Mt. Emei is located exactly at the ecotone between tropical and temperate zonation types in eastern Asia. 相似文献
11.
Vascular plant diversity and climate change in the alpine zone of the Snowy Mountains,Australia 总被引:1,自引:0,他引:1
This study examines vascular plant species richness along an altitudinal gradient in alpine Australia. Vascular plant composition
and soil temperature records were obtained for five summits (from 1729 m to 2114 m a.s.l.) using sampling protocols from the
Global Observation Research Initiative in Alpine Environments program. Species richness was examined against altitude, aspect
and climatic variables at different spatial scales (10 × 10 cm quadrats, 1 m2 quadrats, clusters of 4 * 1 m2 quadrats, for the summit area above a line 5 m altitudinally below the summit (the −5 m isoline), for the extended summit
down to the −10 m isoline). About 75 taxa (70 species, 5 graminoid genera) were recorded, 9 of which are endemic to the small
alpine area of ∼100 km2. There were significant linear relationships between species richness and altitude and climatic variables for the top to
−5 isolines on the summits. However, there was no consistent pattern for species richness at other spatial scales, altitude,
aspect or climatic variables. The proportion of species for the whole summits with localised distributions (local endemics)
increased with altitude. Predicted increasing temperatures and reduced snowcover is likely to result in an increase in species
richness as shrubs, herbs and introduced weeds become more common at higher altitude. Because Australian alpine areas occur
in narrow altitudinal bands with no nival zone, there are no higher altitudinal refuges available for alpine species. Therefore
many of these species are likely to be at risk of extinction from climate change. 相似文献
12.
Diana Selyemová Peter Zach Danka Némethová Ján Kulfan Miroslav Úradník Milada Holecová Branislav Kršiak Katarína Vargová Tomáš Olšovský 《Biologia》2007,62(5):610-616
In two successive years we recorded a total of 3,636 individuals and 17 species of adult lady beetles (Coleoptera, Coccinellidae)
in the spruce forests of Pol’ana Mts (the West Carpathians) at altitudes ranging from 600 m to 1,300 m a.s.l. Four lady beetle
species were documented as predominating (dominance of abundance > 5%) over the study period. They were the following: Aphidecta obliterata (1,828 individuals and 50.3%), Coccinella septempunctata (634 individuals and 17.4%), Adalia conglomerata (594 individuals and 16.3%) and Anatis ocellata (279 individuals and 7.7%). The assemblages of lady beetles differed among the areas and also between the years. The season
revealed neglegible effect on distribution of lady beetles, whereas the effect of altitude was more pronounced. A. conglomerata preferred the areas at lower altitude (600–725 m) to those at middle (900–925 m) and/or upper altitude (1,250–1,300 m). In
contrast, A. obliterata and C. septempuctata were most abundant in the area at middle altitude. The altitudinal location of area partly explained the variability in abundance
of lady beetles. The first ordination axis constructed by means of correspondence analysis (CA) represented an altitudinal
gradient and accounted for 19.4% of the total variance of the species data. The great proportion of lady beetle species not
typically associated with spruce and/or other coniferous trees than spruce (70.6%, n = 17) may be explained by an ecotonal effect. 相似文献
13.
Chlorophyll a and nutrient concentrations along with temperature and salinity values were measured at 22 CTD stations along a 735-km transect
running to the northwest of the island of South Georgia, Southern Ocean. Measurements were repeated during five summer surveys
(January and February 1994, January 1996, December 1996, January 1998) and one spring survey (October 1997). The transect
sampled Sub-Antarctic Zone water in the north, Polar Frontal Zone water and Antarctic Zone water in the south. Chlorophyll
a concentrations were lowest to the north of the transect and frequently high (up to 17 mg m−3) in the deep open ocean of the Antarctic Zone. Sub-surface peaks were measured in all zones and chlorophyll a was detectable to a depth of 150 m. There was a clear latitudinal temperature gradient in the near-surface waters (0–50 m),
the warmest water occurring in the north (∼12 °C), and the coolest in the Antarctic Zone (∼2 °C). There was also a well-defined
latitudinal gradient in summer near-surface silicate concentrations (∼2, 4, and 10 mmol m−3 in the Sub-Antarctic Zone, the Polar Frontal Zone and the Antarctic Zone, respectively), increasing to >20 mmol m−3 near South Georgia. Distinct differences in silicate concentrations were also evident in all three zones to a depth of 500 m.
Near-surface nitrate and phosphate concentrations were relatively low to the north of the transect (∼14 and 1 mmol m−3, respectively) and higher in the Polar Frontal Zone and Antarctic Zone (∼18 and 1.4 mmol m−3, respectively). Ammonium and nitrite were restricted to the upper 200 m of the water column, and exhibited sub-surface concentration
peaks, the lowest being in the Sub-Antarctic Zone (0.68 and 0.25 mmol m−3, respectively) and the highest in the Antarctic Zone (1.72 and 0.29 mmol m−3, respectively). Surface (∼6 m) spring nutrient measurements provided an indication of pre-bloom conditions; ammonium and
nitrite concentrations were low (∼0.27 and 0.28 mmol m−3, respectively), while silicate, nitrate and phosphate concentrations were high and similar to previously measured winter
values (e.g. ∼26, 23, 2 mmol m−3, respectively in the Antarctic Zone). Although the values measured were very variable, and there was some evidence of a seasonal
growth progression, the chlorophyll a and nutrient distribution patterns were dominated by intercruise (interannual) factors. Approximate nutrient depletions (spring
minus summer) appeared similar in the Polar Frontal Zone and Antarctic Zone for nitrate and phosphate, while silicate showed
a marked latitudinal increase from north to south throughout the transect. Highest chlorophyll a concentrations coincided with the highest apparent silicate depletions over the deep ocean of the Antarctic Zone. In this
area, relatively warm, easterly flowing Antarctic Circumpolar Current water meets cooler, westerly flowing water that is influenced
by the Weddell-Scotia Confluence and is rich in nutrients, especially silicate.
Accepted: 27 November 1999 相似文献
14.
Climatic signals in tree ring of Picea schrenkiana along an altitudinal gradient in the central Tianshan Mountains, northwestern China 总被引:2,自引:0,他引:2
Tree-ring samples of Picea schrenkiana (Fisch. et Mey) were studied along an altitudinal gradient in the central Tianshan Mountains, and ring-width chronologies
were developed for three sites at different altitudes: low-forest border (1600–1700 m a.s.l.), interior forest (2100–2200 m
a.s.l.), and upper treeline (2600–2700 m a.s.l.). Annual ring-width variations were similar among the three sites but variability
was greatest at the low-forest border site. The statistical characters of the chronologies showed that mean sensitivity (MS)
and standard deviation (SD) decreased with increasing elevation. In other words, the response of tree growth to environmental
changes decreased with increasing altitude. To understand the differing response of trees at different elevations to the environmental
changes, response function analysis was used to study the relationships between tree-ring widths and mean monthly temperature
and total monthly precipitation from 1961 to 2000. The results showed that precipitation was the most important factor limiting
tree radial growth in the arid central Tianshan Mountains, precipitation in August of the prior growth year played an important
role on tree's radial growth across the entire altitudinal gradient even at the cold, high-elevation treeline site. It is
expected that with increasing altitude air temperature decreased and precipitation increased, the importance of precipitation
on tree growth decreased, and the response of tree growth to environmental changes decreased, too. This conclusion may be
helpful to understand and research the relationship between climatic change and tree growth in arid and semiarid area. 相似文献
15.
Shinichi Yoshihiro Masaru Ohtake Hajime Matsubara Koichiro Zamma Goro Han'ya Yasuaki Tanimura Hiroyuki Kubota Ritsuko Kubo Tatsuhiro Arakane Toru Hirata Mari Furukawa Aki Sato Yukio Takahata 《Primates; journal of primatology》1999,40(2):409-415
A census of wild Yakushima macaques (Macaca fuscata yakui) was carried out in a 23-km2 area of the western coast of Yakushima Island, Japan. We analyzed the census data to investigate changes in monkey distribution
associated with the vertical distribution of vegetation. In the lowland coastal zone of 0–300 m above sea level (a.s.l.),
4.8 troops and 62.4–99.8 monkeys are estimated to have existed per km2. In the mountainside zones of 300–900 m a.s.l., the troop density decreased to 1.3–1.6 troops/km2. Since there was no difference in size between the coastal and mountainside troops, population density should decrease with
altitude to about 30–36 monkeys per km2. On the other hand, 2.4 troops and about 36 monkeys were estimated to have inhabited per km2 in the mountain summit zone of 900–1,323 m a.s.l.
Nature Conservation College 相似文献
16.
Altitudinal distribution of evergreen broad-leaved trees and changes in their leaf sizes were studied on a humid subtropical mountain, Mt. Emei (3099 m a.s.l., 29°34.5 N, 103°21.5 E), Sichuan, China. Among the total woody flora of ca. 540 species, evergreen broad-leaved trees account for 88 species in 39 genera and 23 families, corresponding to the northern limit of subtropical evergreen broad-leaved trees. The number of evergreen broad-leaved tree species greatly decreased from the low-altitudinal, evergreen broad-leaved forest zone (600–1500 m) to the mid-altitudinal, mixed forest zone (1500–2500 m), and to the high-altitudinal, coniferous forest zone (2500–3099 m). The overall trend of reduced leaf size toward upper zones was analyzed and documented in detail. The 88 species were assigned to three leaf-size classes: notophylls (48%), microphylls (36%), and mesophylls (16%). The leaf size was relatively small and the specific leaf weight (SLW, mg cm–2) was much larger in high altitude as compared to low altitude. No overall correlation was found between leaf size and SLW, but leaf size decreased as SLW increased toward high altitude for certain species having relatively wide altitudinal ranges. Moreover, leaf size varied with forest stratification: canopy trees were predominantly notophyllous species, while subcanopy and understorey trees were mainly microphyllous species. The tendency is compatible with the trend found in other mountains of East Asia. 相似文献
17.
Guillermina Massaccesi Fidel A. Roig Guillermo J. Martínez Pastur Marcelo D. Barrera 《Trees - Structure and Function》2008,22(2):245-255
The influence of ecological factors resulting from altitude on growth characteristics of Nothofagus pumilio was analyzed. N. pumilio forests grow in the southern Andes from near sea level to 600 m.a.s.l. Eight study sites were selected in the southwestern
area of Tierra del Fuego, on north- and south-facing slopes, and distributed along an altitudinal gradient (200–600 m.a.s.l.).
Growth cycles throughout time were identified. The correlation between climate and tree growth was determined. Tree diameter
and height decreased whereas stand density increased towards tree-line. South-facing slopes showed higher values in common
growth variability, probably because of stronger climatic controlling factors. Climate-growth correlation models revealed
long-term temperature influences on growth variability, and showed variations among the different plots. Differences were
detected in the spectral power component of the chronologies throughout the altitudinal profile. The series had a significant
spectral peak at frequencies around 7 years, possibly related to mast seeding cycles. This signal became weaker as the altitude
increased probably due to lower seed production. These results suggest a strong altitudinal component in growth variability
of N. pumilio in Tierra del Fuego. 相似文献
18.
We investigated the extent of genetic differentiation among populations of fujihatazao,Arabis serrata along an altitudinal gradient at Mt. Fuji in Shizuoka Prefecture. This species is a perennial plant, widely distributed in
Japan forming small isolated populations. However, at Mt. Fuji, this species constitutes a large population distributed from
1440 to 2400 m altitude. A total of 411 individuals were sampled from ten subpopulations. Eighteen loci were detected on eleven
enzyme systems. Eleven loci were monomorphic and seven loci were polymorphic with a mean of 2.11 alleles per loci. Nei's genetic
distance (mean 0.01) and genetic identity (mean 0.968) were very similar among populations indicating a low genetic differentiation.
The total genetic diversity (H
T
) estimated for the polymorphic loci was, in average, 0.396. The mean gene differentiation (GST=0.091) was very low. Gene frequency of seven polymorphic loci was analyzed by spatial autocorrelation methods based on Moran's
indexes. Only Pgi-3 exhibited a significant negative autocorrelation (−0.160;P<0.05); other loci values ranged from −0.134 to 0.027. Gene flow estimated by indirect methods varied between genes but most
of the values were high (meanNm=20.8) suggesting that subpopulations at different altitudes are probably connected. Despite plants at different altitudes
present different ecological traits (e.g., differences in phenology, growth and reproductive traits), subpopulations ofA. serrata are still low differentiated, at least for the loci studied. This may be explained by the recent origin of some habitats
(e.g., second crater and surrounded areas) in this locality. 相似文献
19.
M. J. Earnshaw K. A. Carver T. C. Gunn K. Kerenga V. Harvey H. Griffiths M. S. J. Broadmeadow 《Oecologia》1990,84(2):280-288
Summary A total of 22 grass species were examined from 5 sites spanning the altitudinal range 1550–4350 m.a.s.l. The presence of the C3 or C4 photosynthetic pathway was determined from 13C values and chilling tolerance was assessed on the basis of electrolyte leakage from leaf slices incubated on melting ice. Most of the grasses studied at the lower altitude sites of 1550 m.a.s.l. (annual mean of daily minimum temperature, 14.6° C) and 2600 m.a.s.l. (9.4° C) possessed C4 photosynthesis and were chill-sensitive. The single except ion was Agrostis avenacea, a montane chill-resistant C3 species which occurred at 2600 m.a.s.l. The three species apparently most sensitive to chilling were Ischaemum polystachyum, Paspalum conjugatum and Saccharum robustum, all occurring at 1550 m.a.s.l. At the higher altitude sites of 3280 (5.6° C), 3580 (4.0° C) and 4350 (–0.7°C) m.a.s.l., most of the grasses exhibited C3 photosynthesis and were chill-resistant. However, an Upland population of the C4 species, Miscanthus floridulus was found at 3280 m.a.s.l. which had acquired chill-resistance as confirmed by additional in vivo variable chlorophyll fluorescence measurements. Cell sap osmotic potential values of the upland grasses at altitudes of 3280–4350 m.a.s.l. were lower (–8.1 to –19.8 bars) than values in grasses from 1550 and 2600 m.a.s.l. (–3.9 to –7.5 bars) due mainly to the presence of non-electrolyte osmoticants, which may be involved in frost avoidance mechanism(s).Abbreviations ABA
abscisic acid
- FR
the maximal rate of rise of induced chlorophyll fluorescence
- s
osmotic potential 相似文献
20.
L. G. Biazrov 《Contemporary Problems of Ecology》2012,5(2):200-207
The d15N values of stable nitrogen isotopes were determined in samples of organic matter (OM) of thalli of vagrant lichen Xanthoparmelia camtschadalis collected across 13 altitudinal levels within the range of 1550–3250 m above sea level of both steppes and highland meadows
of the Khangai Plateau of Mongolia. No correlation between the d15N values of lichen OM and the altitude range was detected at the regional scale. However, at a local scale including vegetation
type, botanical-geographical area of Khangai, and mountain slope, the amount of the 15N heavy isotope in lichen OM was found to be decreased with an altitude increase. 相似文献