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1.
Forest vegetation of a community managed forest (Van Panchayat) located between 1570–1700 m elevation was studied along four
aspects. Quercus leucotrichophora was the dominant species on three of the four aspects. Across the aspects the total tree density ranged between 150 and 490
ind/ha, sapling density between 100 and 370 ind/ha, seedling density varied from 241 to 1090 ind/ha. The shrub density ranged
from 166 to 690 ind/ha and herb density from 6000–17100 ind/ha. The total basal area of tree layer varied from 9.78 to 13.5
m2/ha showing that the forest is young. Species diversity value for tree layer varied from 0.14 to 1.69. Quercus leucotrichophora were regenerating well due to effective forest management by local communities. The higher proportion of seedlings of Quercus leucotrichophora indicating that the Van Panchayat are playing important role in conservation of oak forest of Himalaya. 相似文献
2.
Renyan Duan Chao Wang Xiao-an Wang Zhihong Zhu Hua Guo 《Russian Journal of Ecology》2009,40(7):501-509
We compared differences in plant species diversity between conifer (Pinus tabulaeformis) plantations and natural secondary forests in the middle of the Loess plateau. The goal of the study was to examine the differences
in the effect of stand development on species diversity and in species responses to changes between forest types and between
forest layers. To clarify the effects of differences in forest management, we emphasized the functional types of plant species
occurring in each forest type. The result as follow: (1) The H′ and S of tree layer were significantly lower in natural conifer forest than old conifer and secondary forest, but were not different
compared with mid aged conifer forest. The H′ and S of shrub layer were significantly lower in mid aged conifer forest compared with other forest types. The H′ of herb layer showed no significant differences in the four forest types. The evenness index (J′) of tree layer of mid aged conifer forest was lower than other forest communities and its J′ of shrub layer was highest although its richness of shrub layer was lower than in the other forest types. (2) The analysis
of β diversity index also indicated large differences between conifer plantations and natural forests. Although the tree layer
species were similar in old plantation and natural conifer forests, they differed greatly between the natural conifer and
secondary forests. The natural conifer and secondary forest species composition in shrub layer differed significantly from
those in plantation and secondary plots. Tree species were significantly less common in plantations than in abandoned coppice
forests. Species composition in the herb layer of different forest types was similar. (3) The management of P. tabulaeformis plantations alters plant species composition considerably; the number of sub tall-tree species is increased in old aged conifer
forest, especially species dispersed by animals. Plantation management appears to affect ecological processes through seed
dispersal. From the perspective of management, the change in the structure and composition of the canopy in plantations could
affect the behavior of dispersers and regeneration. 相似文献
3.
S. N. Sannikov I. V. Petrova N. S. Sannikova E. V. Egorov T. V. Filippova 《Russian Journal of Ecology》2011,42(3):186-191
Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island
model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range
boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below
15–20 km2 and increases to the level observed in the center of the range when the population area exceeds 50–100 km2. A chorogenetic classification of marginal P. sylvestris populations is proposed. 相似文献
4.
Forest structure and regeneration along the altitudinal gradient in the Binsar Wildlife Sanctuary,Uttarakhand Himalaya,India 总被引:1,自引:0,他引:1
Forest structure and regeneration were studied along the altitudinal gradient in the Binsar Wildlife Sanctuary of Uttarakhand
Himalaya in India. Stratified random sampling of tree species was done by placing minimum 15 quadrats of 10 × 10 m at each
aspect and altitude. The results reveal that along the altitudinal gradient there were three types of forest communities in
the Sanctuary viz., chir pine (Pinus roxburghii), oakchir pine (Quercus leucotrichophora and Pinus roxburghii) and oak (Quercus floribunda and Quercus leucotrichophora). Rhododendron arboreum, Cornus macrophylla and Lyonia ovalifolia were main associates of these forest communities. The oak forests had larger shrub population as compared to chir pine. Myrsine africana was the most dominant shrub across the altitudinal gradient, whereas few shrub species were restricted to a certain altitudinal
range. The regeneration of chir pine was best at lower altitude on south and east aspects, which indicates that it mostly
regenerates on warm and dry slopes. In general, the regeneration potential in most of the tree species declines with the altitude.
The density of saplings and seedlings also represented the dominant species at each altitudinal range, which indicates the
cyclic regeneration of forests in the Sanctuary area. 相似文献
5.
Tommaso Chiti Giacomo Certini Lucia Perugini Giovanni Mastrolonardo Dario Papale Riccardo Valentini 《Regional Environmental Change》2011,11(2):371-376
The purpose of the present work is to asses the possibility of detecting changes in soil organic carbon (SOC) at the end of
the 5-years of the first Commitment Period (CP) of the Kyoto Protocol of the United Nation’s Framework Convention on Climate
Change (1 January, 2008–31 December, 2012), by both direct measurement and the use of an opportunely evaluated SOC model,
CENTURY. The investigated soil is young, developed since 28 years on virtually C-free spoil banks and under the influence
of two managed forest stands, one a mix of English oak (Quercus robur L.) and Italian alder (Alnus cordata Loisel.) and the other pure English oak. The SOC stock of either stand was monitored since the time the stands were planted
in 1981, and it was used together with other parameters for the model evaluation, while the future projections for the end
of the first (2012) and second (2017) CP were made according to two extreme IPCC climatic scenarios: A1F1, the most dramatic,
and B2, among the less impacting. Direct SOC measurements performed at the beginning and at the end of a time frame equivalent
to a commitment period (2004–2008) had not shown significant variations in either stands. Compared to the 2008 SOC stock,
in both stands the model shows variations at the end of the first CP from 0.7 to 1.8 Mg C ha−1 for the A1F1 scenario and from 0.3 to 1.7 Mg C ha−1 for the B2. These variations are within the standard deviations of the C stocks measured in 2008. On the contrary, at the
end of the second CP, the modelled SOC increments range from 2.5 to 3.6 Mg C ha−1 (A1F1) or from 1.9 to 3.4 Mg C ha−1 (B2), indicating the possibility to detect the SOC changes by direct measurement, since the values well agree with the minimum
detectable variation estimated for both sites in 3.3–4.5 Mg C ha−1. This work shows that SOC stock changes measured directly in the field can be minimal at the end of both CPs, and that CENTURY
well simulates the SOC dynamics of the stands. The use of such a model, validated at long-term experimental sites, hence represents
an effective tool for estimating future changes in SOC amounts in support of direct measurements when a short period of time,
such as the CP, is considered. 相似文献
6.
Rupert Seidl Mart-Jan Schelhaas Marcus Lindner Manfred J. Lexer 《Regional Environmental Change》2009,9(2):101-119
To study potential consequences of climate-induced changes in the biotic disturbance regime at regional to national scale
we integrated a model of Ips typographus (L. Scol. Col.) damages into the large-scale forest scenario model EFISCEN. A two-stage multivariate statistical meta-model
was used to upscale stand level damages by bark beetles as simulated in the hybrid forest patch model PICUS v1.41. Comparing
EFISCEN simulations including the new bark beetle disturbance module against a 15-year damage time series for Austria showed
good agreement at province level (R2 between 0.496 and 0.802). A scenario analysis of climate change impacts on bark beetle-induced damages in Austria’s Norway
spruce [Picea abies (L.) Karst.] forests resulted in a strong increase in damages (from 1.33 Mm3 a−1, period 1990–2004, to 4.46 Mm3 a−1, period 2095–2099). Studying two adaptive management strategies (species change) revealed a considerable time-lag between
the start of adaptation measures and a decrease in simulated damages by bark beetles. 相似文献
7.
Pinus roxburghii (chir-pine) and Quercus leucothchophora (banj-oak) are dominant forests of mountainous part of the Uttarakhand Himalaya. The continued anthropogenic disturbance
is opening the canopy, forming canopy gaps and as a result forest fragments are developing. Thus, the present study aims to
analyze variations in species richness and vegetational parameters in relation to canopy gaps in forests. Total species richness
was greater in open canopied forest compared to moderate and close canopied forests. In comparison between oak and pine forest,
it was greater in oak forest while the proportion of common species was low between oak—pine forests. Mean species richness
did not significantly vary from one canopy gap to another as well as in oak and pine dominated forest. This indicated that
dominant forest types played an important role to form the community structure. The shrubs richness were greater in closed
canopy and between the forests it was greater in pine forest. Tree and shrub density was low in open canopy while herb density
was high in moderate canopy. Thus, this study indicated that the dominant canopy species play an important role in deciding
the community structures especially the distribution of under canopy species. These parameters should be considered for conservation
and maintenance of plant biodiversity of a region. 相似文献
8.
M. Katsuyama H. Shibata T. Yoshioka T. Yoshida A. Ogawa N. Ohte 《Sustainability Science》2009,4(2):179-188
We simulated hydrological and biogeochemical responses to logging in a forested watershed to determine the vulnerability and/or
resiliency of the forest ecosystems in the Lake Shumarinai Basin in northern Hokkaido, Japan. We used a biogeochemical model
(PnET-CN) and a rainfall–runoff model (HYCYMODEL) to predict ecosystem responses. The PnET-CN model simulated well the observed
NO3
− concentrations in streamwater, particularly at high concentrations during snowmelt; however, the model could not simulate
small increases in NO3
− during the summer. By considering hydrological processes within the watershed and combining the model with the HYCYMODEL
(PnET + HYCYMODEL), the seasonality of streamwater NO3
− concentrations was better simulated. Using these models, the long-term effects of logging were simulated for coniferous,
deciduous, and mixed forests. NO3
− concentrations in streamwater increased in response to the logging disturbance in both coniferous and deciduous forests.
In the coniferous forest, NO3
− concentrations reached a maximum 10 years after logging, and high concentrations persisted for 30 years. In contrast, NO3
− concentrations in the deciduous forest reached a maximum within 3–4 years and recovered to pre-disturbance levels after 15 years.
We also used the models to determine the effects of different sizes and types (coniferous, deciduous, and mixed forest) of
logging areas on Lake Shumarinai. The model results indicated that large areas of cutting require more than 100 years for
complete lake recovery. Whereas the annual discharge to the lake minimally increased, the annual NO3
− load greatly increased. Our simulation results elucidate the vulnerability and resiliency of forest ecosystems and provide
valuable information for ecosystem management. 相似文献
9.
N. G. Smirnov E. A. Kuz’mina I. B. Golovachev T. V. Fadeeva 《Russian Journal of Ecology》2007,38(2):106-111
On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal
rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special
attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation
in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic
features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years
(transition from the Holocene optimum to the present-day climate and state of the natural environment).
Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123.
The article was translated by the authors. 相似文献
10.
Petra Lasch Chris Kollas Joachim Rock Felicitas Suckow 《Regional Environmental Change》2010,10(2):83-94
Woody biomass generated in short-rotation coppice (SRC) plantations with aspen (Populus tremula L.) has good properties for bioenergy crop production: annual yields are high, labour input per year is low, and it is ecologically
valuable because of the multi-year rotation periods. Eastern Germany has a special advantage in producing bioenergy crops:
the former “agricultural cooperatives” built up quite large farms with, compared to Western Germany, comparatively large fields.
Therefore, a modelling study of the potential and the impacts of aspen SRC plantations in the five eastern federal states
of Germany under the recent climate and future climate projections was conducted. The ecophysiological forest growth model
4C was used to simulate the growth of aspen SRC plantations and their impacts on carbon in soils, and groundwater recharge,
on selected suitable areas currently under crops but with marginal site conditions for cropping. A clear signal to enhanced
growth condition over the whole area can be seen in the simulation of the mean annual woody biomass yield under conditions
of climate change, which increased from 7.47 t DW ha−1 a−1 under the recent climate to 9.26 t DW ha−1 a−1 at the end of the considered future period 2034–2055 under climate change. The mean soil carbon sequestration rate was 0.81 t C ha−1 a−1 under the recent climate and could rise up to 0.93 t C ha−1 a−1 under the assumption of climate change. On the other hand, the mean annual percolation rate, used as an indicator of impacts
on the regional water budget, will diminish under future climatic conditions. The results suggest that aspen SRC plantations
are a suitable contribution to regional CO2 mitigation and carbon sequestration under possible change of climate, but that negative impacts on the regional water budget
are possible. 相似文献
11.
Fuelwood is the only important source of energy in the mountainous region of the Garhwal Himalaya, India. Since the commercial
source of energy is generally beyond the reach of ordinary people due to their poor socio-economic conditions and due to limited
supply and lack of communication facilities for transport of LPG, the villages of the inner region of the Garhwal Himalaya
depend on their fuel requirement from the forest. In the present study, two villages of the Nanda Devi Biosphere Reserve in
Uttarakhand part of the Indian Himalaya i.e. Lata and Dunagiri located at 2,415 and 3,600 m altitudes, respectively, were
selected for the study of socio-economic profile and vegetation and for estimation of per capita fuelwood consumption and
the degree of disturbance. The study was conducted from 2002–2005. The population of these villages is migratory and belongs
to the Bhotiya community, a scheduled tribe consisting of two subgroups known as Tolcha and Marchha. They grow traditional crops as well as cash crops. Important tree species used for fuelwood include Cedrus deodara, Pinus wallichiana, Cupressus torulosa, Taxus wallichiana, Acer indicum, Quercus dilatata and Viburnum cotinifolium. Maximum density among trees was shown by Pinus wallichiana (169.6 trees ha−1) in village Lata and by Cedrus deodara (89.6 trees ha−1) in village Dunagiri. The average per capita consumption of fuelwood in villages Lata and Dunagiri was 4.03 and 4.77 kg capita−1 day−1. Maximum number of trees (29 and 31% lopping for Lata and Dunagiri, respectively) belonged to disturbance class 1 (1–20%
lopping) followed by the disturbance class 2 (20–40% lopping). Due to location of these villages in the buffer zone of the
biosphere reserve, the fuelwood consumption may cause an adverse impact on the ecological status of this reserve, which urgently
requires employing strategies for the conservation and management of this biosphere in terms of fuelwood sustainability e.g.
regulation of livestock stock and grazing, using alternative sources of fuels, plantation of multipurpose trees and adoption
of ecotourism. 相似文献
12.
A. J. Plater J. F. Boyle C. Mayers S. D. Turner R. W. Stroud 《Regional Environmental Change》2006,6(1-2):71-85
The limnological record of human impact on catchment land cover and on lake sedimentation during the historical period has
been established for Pinto Lake in Central Coastal California. In addition, the sedimentary record of the ‘pre-impact’ condition
preserves evidence of a climatic control on the nature of lake sedimentation. Chronological marker horizons have been determined
using pollen data in combination with the documented land-use history and introductions of exotic species. Further chronological
data have been determined using 14C and 137Cs. The impact of Mexican and Euro-American immigrants and their ‘imported’ land-use practices is clearly reflected in an
order of magnitude increase in the rate of lake sedimentation to c. 9 kg m−2 year−1 (c. 2 cm year−1) between 1770 and 1850. Here, the occurrence of exotic plant species indicates disturbance as early as c. 1769–1797, whilst
redwood deforestation between 1844 and 1860 represents the most significant human impact. Changes in the nature of sedimentation
prior to this reveal a high degree of sensitivity to changes in precipitation where subtle decreases in lake level and the
supply of runoff-derived mineral matter have resulted in two periods of organic lake sedimentation c. 650–900 and 1275–1750. Set against this background condition of high sensitivity, the dramatic impacts of Euro-American settlement
are unsurprising.
An erratum to this article can be found at 相似文献
13.
Ahmad Barati Asieh Aliakbari Seyed Mahmoud Ghasempouri 《Russian Journal of Ecology》2011,42(4):315-320
Variations in breeding success of the Whiskered Terns (Chlidonias hybrida) were studied in two wetlands; Anzali (2005 and 2008) and Zarivar (2007–2008) in north and west Iran. Nesting success was
modeled and compared using information-theoretic approach implemented in program Mark in order to assess effects of colony
locations, years and nest initiation dates on the probability of daily nest survival. Clutch size did not vary between colonies
and years. Breeding success varied between colonies (Zarivar > Anzali), and years only in Anzali (2005 > 2008). Overall daily
nest survival was 0.977. (95% LCI 0.973, UCI 0.981), equivalent to a Mayfield nest survival of 0.317. (95% LCI 0.255, UCI
0.387). Egg-laying periods and colony site were important covariates affecting the daily survival rates (Σω
i
= 0.86 and Σω
i
= 0.83, respectively), while, the support for the effect of year was less (Σω
i
= 0.41). We concluded that Lake Zarivar provides a more favorable nesting location for Whiskered Terns probably because of
little changes in rainfall and water depth during the breeding seasons which influence breeding performance. 相似文献
14.
A. G. Vasil’ev I. A. Vasil’eva Yu. V. Gorodilova M. V. Chibiryak 《Russian Journal of Ecology》2010,41(2):153-158
To test the hypothesis that morphological disparity increases while taxonomic diversity decreases in a radioactively contaminated
environment, the relationship of these parameters was studied in communities (taxocenes) of rodents living in the Southern
Urals in the zone of influence from the Eastern Ural Radioactive Trace (EURT) (2003–2008). Young of the year of six rodent
species (98 samples) were examined in the background (control) area (0.2 Ci/km2) and in the impact area polluted with radionuclides from the EURT (750 Ci/km2). The dynamics of morphological disparity (MD), assessed with regard to average values of five exterior characters, was compared between the control and impact taxocenes.
Taxonomic (taxocenotic) diversity was estimated with the Shannon index (H). Morphological disparity was found to increase significantly at low rodent abundance (in conditionally unfavorable years)
and decrease at high abundance, with the value of MD in the impact taxocene being significantly higher. A negative correlation between MD and H was revealed (r = −0.70), in conformity with the above hypothesis. Discordance (difference in direction) of annual changes in the test parameters,
with H increasing while MD decreases (or vice versa) was observed in unfavorable years; it can be used as an indicator of conditions unfavorable for
rodent taxocenes. 相似文献
15.
S. S. S. Sarma Saúl Avelino Rivera Fabiola Elizalde Hinojosa S. Nandini 《Russian Journal of Ecology》2007,38(5):353-362
We tested separately the effect of two taxonomically related rotifers (B. patulus and B. macracanthus) on the population dynamics of another species (A. fissa) at low (0.5 ×10 6) and high food levels (1.5 × 106 cells/ml of Chlorella vulgaris) using different inoculation densities (0–100%). We also quantified the impact of A. fissa on the two brachionid species. Regardless of the presence of the competing species, an increase in the availability of food
led to increase in the abundances of the three rotifers. The population growth of B. patulus, B. macracanthus, or A. fissa was affected negatively when cultured together with another species. An increase in the initial density of any one of the
competing species became advantageous to maintain a certain population size. At a low algal food level, B. patulus was able to suppress A. fissa more strongly than B. macracanthus. On the other hand, at a high food level, B. macracanthus suppressed the population of A. fissa more strongly than B. patulus. Peak population densities for A. fissa varied from about 150 to 1000 ind./ml, depending on food density and the presence of competitors. The rate of population
increase (r) of A. fissa, B. patulus, and B. macracanthus increased with an increase in food availability but decreased with increasing initial density of the competitor. Both Brachionus spp. experienced negative growth rates in the presence of A. fissa, especially at a high initial density of the latter.
Published in Russian in Ekologiya, 2007, Vol. 38, No. 5, pp. 381–390.
The article was submitted by the authors in English. 相似文献
16.
Miglena Zhiyanski Maria Sokolovska Alexandros Clouvas Viktor Badulin 《Journal of environmental radioactivity》2010,101(10):864-868
This study focuses on the cesium-137 (137Cs) contamination in grass and in different compartments of oak trees growing in ecosystems, located in the zone with sub-mediterranean climate in South Bulgaria, characterized with high summer temperatures, low precipitation and often periods of drought. In 2008, three experimental sites - PP1, PP2, PP3 - were sampled in oak ecosystems from Maleshevska Mountain at 900 m above sea level. Samples from grass species and oak tree leaves, branches with different diameter, wood disks and bark were analyzed for 137Cs activity with γ-spectrometry. The soil-to-plant transfer factor (TF) values for 137Cs were estimated differentiating different tree compartments. Our findings showed relatively high activity concentrations of 137Cs in oak trees even 22 years after the Chernobyl accident. The grass under oak was less contaminated compared with the oak trees. The different organs of oak trees could be distinguished according to the 137Cs contamination as follows: bark > branches (d < 1 cm) > leaves > branches (d > 3 cm) > wood. The relatively higher contamination of bark compared with the new-formed biomass suggested that a significant part of 137Cs was accumulated as a result of direct adsorption at the time of the main contamination event. The TF values obtained and the presence of 137Cs in the branches, leaves and in the wood formed after 1986 confirmed that 22 years after the contamination, the main mechanism of 137Cs entrance in tree biomass was the root uptake. 相似文献
17.
Masahiko Matsuda 《Environment, Development and Sustainability》2011,13(1):51-64
This study aims to estimate the intensification of rice farming in Myanmar particularly due to chemical fertilizer application,
using farm-level data obtained from field surveys conducted in the 2000s. Relatively high-input rice farming was found in
dry season crop in the delta zone and the double crop in well-irrigated lowlands of the central dry zone. The chemical fertilizer
used there was about 88–159 kg NPK (nitrogen, N; phosphate, P2O5; and potash, K2O) ha−1 (76–110 kg nitrogen (N) ha−1), and the average paddy yield ranged from 2.8 to 3.5 ton ha−1. On the other hand, nutrient input in survey sites of rain-fed lowland was between 11 and 53 kg NPK ha−1 (5 and 36 kg N ha−1), and the yield ranged from 1.1 to 2.3 ton ha−1. The national average of paddy yield and nutrient input of fertilizer was roughly estimated to be around 2.4 ton ha−1 and 60 kg NPK ha−1, respectively. A gap was observed between these calculated values and the official statistics. A comparison of fertilizer
use efficiency for rice production in Myanmar with that in China and Vietnam has shown that the efficiency in Myanmar has
not declined to an inappropriate level even in its intensive ones. Rice production in Myanmar has room for increasing the
yield by capital intensification. Nevertheless, considering its sustainability as well as productivity, further intensification
in rice farming technology in irrigated lowlands of Myanmar may neither be the best nor the only way. 相似文献
18.
Horst Behrendt Matthias Kornmilch Dieter Opitz Oliver Schmoll Gaby Scholz 《Regional Environmental Change》2002,3(1-3):107-117
The nutrient discharges from point and diffuse sources in more than 200 German river basins were estimated for the periods
1983–1987 and 1993–1997 employing the MONERIS model. This model distinguishes between six diffuse pathways and point source
emissions from waste water treatment plants and direct industrial discharges. It was estimated that the total nitrogen input
into the German river systems amounts to about 819,000 t N year–1 in the period 1993 to 1997. These emissions have decreased since the mid-eighties by about 266,000 t N year–1, mainly caused by the reduction of point discharges. For phosphorus the emissions have been reduced by 56,290 t P year–1 and amount to 37,250 t P year–1 in the period 1993–1997. Based on emission data a retention module estimates riverine nutrient loads. The comparison of the
model output with the observed loads shows a deviation as low as 30% and 50% for nitrogen and phosphorus, respectively. The
regional resolution of the model indicates the relative importance of different pathways for phosphorus and nitrogen input
into river systems.
Electronic Publication 相似文献
19.
M. A. Potapov I. V. Zadubrovskaya P. A. Zadubrovskii O. F. Potapova V. I. Evsikov 《Russian Journal of Ecology》2012,43(1):40-44
A comparative analysis of reproductive behavior has been performed in the steppe lemming (Lagurus lagurus) and narrow-skulled vole (Microtus gregalis). The results show that the species are similar in certain behavioral features indicative of the stability of mating pairs.
However, in the narrow-skulled vole, unlike in the steppe lemming, mature males in olfactory tests show preference for receptive
sibling females versus non-kin females. Probably, it is the absence of the incest taboo that allows the involvement of young
of the year in reproduction within growing family groups and accounts for “coloniality” of the species. 相似文献
20.
Anttila A Leppänen AP Rissanen K Ylipieti J 《Journal of environmental radioactivity》2011,102(7):659-666
Samples of summer pasture plants that reindeer feed on were collected in order to study 137Cs concentrations in different plant species and in species nested in certain site types, and to study the regional distribution of 137Cs in the Finnish reindeer management area. Plant species were categorized by the site types of mineral soil forest (xeric heath forest and mesic heath forest) and peatland. A third category called ’other plant species’ included plants with various site types, poorly determined species and species with poor statistics. The 137Cs concentrations in different site types differed significantly. The mean 137Cs concentrations of the whole reindeer management area in the xeric heath forest plant species was 44 ± 27 Bq/kg dw, in the mesic heath forest plant species 75 ± 59 Bq/kg dw and in the peatland plant species 219 ± 150 Bq/kg dw. The peatland species uptake 137Cs more efficiently than plant species of mineral soil forests. A particularly efficient collector of 137Cs was Trichophorum sp. It is suggested that Trichophorum sp. could be used as an indicator species for reindeer summer fodder plants. The highest concentrations of 137Cs were found in Southern Lapland and the lowest in Northern Lapland. Today, the concentrations of 137Cs in summer pasture plants that reindeer feed on in Finland are at such a level that there is no need to avoid any plant species. In the case of future nuclear fallout, reindeer grazing in peatlands would increase concentrations of 137Cs in reindeer meat. 相似文献