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61.
《Fungal Ecology》2017
Biodiversity surrogates are commonly used in conservation biology. Here we review how fungi have been used as such in forest conservation, emphasizing proposed surrogate roles and practical applications. We show that many fungal surrogates have been suggested based on field experience and loose concepts, rather than on rigorously collected scientific data. Yet, they have played an important role, not only in forest conservation, but also in inspiring research in fungal ecology and forest history. We argue that, even in times of ecosystem oriented conservation planning and molecular tools to analyze fungal communities, fruit bodies of macrofungi have potential as convenient conservation shortcuts and easy tools to communicate complex biodiversity for a broader audience. To improve the reliability of future fungal surrogates we propose a three step protocol for developing evidence based schemes for practical application in forest conservation. 相似文献
62.
This study obtained baseline information for adult Odonata and assessed their conservation priorities and suitability as biological
indicators in S’Albufera Natural Park in Mallorca, Spain. At this site, human activities in and around the wetland have raised
concerns about their impact on the ecosystem. Investigations on adult diversity produced records of 14 species (four Zygoptera
and 10 Anisoptera) and included the first record of Erythromma viridulum for the park. Detrended Correspondence Analysis (DCA) ordination categorised study sites according to their geographical
locations in the park and showed clustering of the sites around particular species based on these locations. This pattern
might reflect the differences in brackishness in water supplied by different water sources. Canonical Correspondence Analysis
(CCA) indicated that some environmental factors were related to particular species. Water flow, vegetation, and depth and
size of a water body could discriminate stenotopic species from eurytopic species. Only a few species appeared to be tolerant
to the sites with high salinity and low oxygen concentration. The ordination results can be useful for establishing conservation
priorities with information of species diversity, abundance, distribution and flight period. Although, with the current limited
basic information, the use of Odonata species as biological indicators seems to be difficult, some clear relationships between
environmental factors and particular species indicate the great potential of using adult Odonata as biological indicators
in the park. 相似文献
63.
Aquatic oligochaetes are abundant in polluted areas and are, therefore, commonly used as bioindicators to study organic pollution
in rivers and streams. In order to develop a species-level oligochaete biotic index to reflect the River Pollution Index (RPI)
in the Taichung Water Basin in Taiwan, we conducted a systematic sampling scheme to collect aquatic oligochaetes from the
sediment samples of watercourses in the Taichung Water Basin, Taiwan. We evaluated the relationships between aquatic oligochaetes
and the sewage pollution using statistical methods. The distribution of aquatic oligochaetes in relation to environmental
variables, such as water quality and sediment characteristics of the regional urban contaminated streams was expressed by
Canonical Correspondence Analysis (CCA). We identified 17 species of aquatic oligochaetes (Annelida, Clitellata) including
3 species of Tubificidae, 13 species of Naididae, and 1 species of Enchytraeidae from the watercourses of an urban region
in the Taichung Water Basin in Taiwan, during the summer and winter of 2005 and 2006. A positive correlation was found between
the total abundance of aquatic oligochaetes and the RPI (r = 0.58, P < 0.05). However, only population density of the most abundant tubificid, Limnodrilus hoffmeisteri, increased with increasing RPI values and a significantly negative correlation was found between the population density of
the naidid, Nais
communis, and RPI values. The results of CCA indicated that certain naidids, such as Aulophorus furcatus and Allonais
gwaliorensis also tolerated extremely polluted environments in upper stream or stony habitats, implying that tubificids should not be
the sole representation of simple biotic indices but should also include pollution-tolerant naidids. We found that the community
structure of aquatic oligochaetes was influenced by short-term variations in microhabitat rather than according to seasonal
factors in our study region. The results proved that aquatic oligochaetes were sensitive enough to provide a supplement for
the regional urban pollution assessment applications for biotic indicators at the species-level. 相似文献
64.
Identifying indicator plant species of habitat quality and invasibility as a guide for peri-urban forest management 总被引:1,自引:0,他引:1
A floristic survey has been carried out in a peri-urban forest, the Sonian Forest in Brussels, to identify indicator plant species in the herbaceous layer, which could be used as an aid within the framework of a more sustainable management of the forest. Three hundred and seventy two (372) taxa have been identified, 33 of which are non-native (i.e. non-indigenous species regarding the study area, whether invasive or not). Criteria of habitat quality that have been chosen are the species richness, the commonness of the habitat, based on constitutive species, and its invasibility (vulnerability for invasion). On the basis of a comparison of the value of these criteria when each considered (potential indicator) species is present or not, 17 species have been recognised as reliable indicators of at least one of these three criteria. In particular, vegetation types containing either Anthriscus sylvestris, Galeopsis tetrahit or Senecio ovatus were found to be more susceptible to invasion than other habitats. The way to how the predictability of invasions might be effectively used as a management tool is discussed. Furthermore, we found a positive significant correlation (Bonferroni corrected probabilities) between the species richness and luminosity factor (derived from Ellenberg's indices), and the proportion of grassland and wetland species. The species richness was significantly negatively correlated with the proportion of woodland species. An increase in commonness was significantly correlated with a decrease in the proportion of geophytes. The usefulness of these results as an ecological basis for forest management is discussed. 相似文献
65.
Ecological species groups of landform-level ecosystems dominated by jack pine in northern Lower Michigan,USA 总被引:1,自引:0,他引:1
A combination of field and tabular methods and multivariate analyses were used to develop groups of ground flora species (i.e., ecological species groups) that characterize and distinguish highly disturbed, landform-level ecosystems dominated by jack pine in northern Lower Michigan. The endangered Kirtland's warbler formerly or currently occupied the large glacial landforms for which species groups were developed. Eight such ecological species groups were created using 31 woody and herbaceous species sampled in 144 plots within a 20,000 km2 geographic region of uniform climate and regional physiography. The groups were initially constructed using subjective, observation-based groupings of species with similar presence and abundance along soil moisture and fertility gradients. Species groups were corroborated using TWINSPAN and detrended correspondence analysis, and the environmental conditions indicated by each were described and contrasted based upon field observations and canonical correspondence analysis. Two of the eight species groups indicated very dry, infertile sites, and one was indicative of a very broad range of sites dominated by jack pine. The remaining five groups reflected a relatively gentle environmental gradient within the set of ecosystems we sampled, indicating small differences along a soil moisture gradient and less so along a soil fertility and light availability gradient. The groups were applied successfully for the majority of an area that had been repeatedly logged and/or burned for at least 120 years. In addition, the groups were successful when tested on sites with highly disturbed upper soil strata furrowed for the establishment of plantations between the 1960s and 1980s. Within the boundaries of the regional ecosystems for which they were developed, ecological species groups reflect the integrated effects of multiple site factors that control the height growth rates of jack pine trees that, in turn, determine the duration of Kirtland's warbler occupancy. While usually applied at the scale of ecosystem types, our results demonstrate that ecological species groups may also provide the ecological basis for distinguishing ecosystems at broader scales. When examined simultaneously in the field with physiography, microclimate, and soil factors, the groups are therefore useful in identifying and classifying ecosystem units at the scale of landforms, the appropriate scale of management for the Kirtland's warbler. 相似文献
66.
Summary . We propose a new statistical method for obtaining information about particle size distributions from sectional data without specific assumptions about particle shape. The method utilizes recent advances in local stereology. We show how to estimate separately from sectional data the variance due to the local stereological estimation procedure and the variance due to the variability of particle sizes in the population. Methods for judging the difference between the distribution of estimated particle sizes and the distribution of true particle sizes are also provided. 相似文献
67.
Denitrification efficiency for defining critical loads of carbon in shallow coastal ecosystems 总被引:2,自引:2,他引:0
Denitrification efficiency [DE; (N2 − N/(DIN + N2 − N) × 100%)] as an indicator of change associated with nutrient over-enrichment was evaluated for 22 shallow coastal ecosystems
in Australia. The rate of carbon decomposition (which can be considered a proxy for carbon loading) is an important control
on the efficiency with which coastal sediments in depositional mud basins with low water column nitrate concentrations recycle
nitrogen as N2. The relationship between DE and carbon loading is due to changes in carbon and nitrate (NO3) supply associated with sediment biocomplexity. At the DE optimum (500–1,000 μmol m−2 h−1), there is an overlap of aerobic and anaerobic respiration zones (caused primarily by the existence of anaerobic micro-niches
within the oxic zone, and oxidized burrow structures penetrating into the anaerobic zone), which enhances denitrification
by improving both the organic carbon and nitrate supply to denitrifiers. On either side of the DE optimum zone, there is a
reduction in denitrification sites as the sediment loses its three-dimensional complexity. At low organic carbon loadings,
a thick oxic zone with low macrofauna biomass exists, resulting in limited anoxic sites for denitrification, and at high carbon
loadings, there is a thick anoxic zone and a resultant lack of oxygen for nitrification and associated NO3 production. We propose a trophic scheme for defining critical (sustainable) carbon loading rates and possible thresholds
for shallow coastal ecosystems based on the relationship between denitrification efficiency and carbon loading for 17 of the
22 Australian coastal ecosystems. The denitrification efficiency “optimum” occurs between carbon loadings of about 50 and
100 g C m−2 year−1. Coastal managers can use this simple trophic scheme to classify the current state of their shallow coastal ecosystems and
for determining what carbon loading rate is necessary to achieve any future state.
Guest editors: J. H. Andersen & D. J. Conley
Eutrophication in Coastal Ecosystems: Selected papers from the Second International Symposium on Research and Management of
Eutrophication in Coastal Ecosystems, 20–23 June 2006, Nyborg, Denmark 相似文献
68.
Idalia Kasprzyk 《International journal of biometeorology》2009,53(4):345-353
Forecasting the time when the atmospheric pollen season of allergenic plants begins is particularly important for doctors
and their patients. The aim of this paper is to determine whether it is possible to forecast the start of the oak (Quercus) pollen season in Rzeszów, Poland. In the elaboration of the most effective model, various forecasting techniques were tested:
growth degree days (GDD°C); meteorological factors; bioclimatic factors; and indicator taxon. The aerobiological monitoring
was carried out in 1997–2005 and 2007 in Rzeszów (SE Poland). In the presented investigation, three methods defining the start
of the Quercus pollen season were selected on the basis of accumulated sums of pollen or the constant occurrence of pollen grains in air.
Despite the application of different combinations of GDD°C methods and threshold temperatures, the correlation coefficients
between the expected and obtained values were low. In some cases, however, they proved highly effective for the test years
(2005, 2007) with the accuracy of a few days. For GDD°C methods, the best threshold temperatures range between 5 and 6°C.
Models based on bioclimatic indices and meteorological variables were not satisfactory. On the basic of the 10 years of results,
the method of indicator species were good for forecast the start of oak pollen season. Birch was the best indicator taxa. 相似文献
69.
Erna Suutari Jukka Salmela Lauri Paasivirta Markus J. Rantala Katja Tynkkynen Mari Luojumäki Jukka Suhonen 《Journal of Insect Conservation》2009,13(4):413-419
Species with narrow ranges and specialised traits are most at risk, and the extinction wave is further enhanced by coextinctions.
We studied the conservation value and indicator potential of Stratiotes aloides, an aquatic macrophyte that has declined considerably in Europe. Our purpose was to determine whether S. aloides could be used as an indicator of a valuable habitat in terms of macroarthropod diversity and species richness. The potential
occurrence of an internationally endangered Stratiotes-habitat specialist, the dragonfly Aeshna viridis, can increase the conservation value of plant colonies. S. aloides beds harboured diverse macroarthropod fauna often containing species of conservation concern, including A. viridis. Stratiotes is a potential indicator of a valuable habitat, and its indicator value is enhanced by the easy identification of the species.
However, its use as an indicator of a defined macroarthropod community is limited because no particular community type is
connected to it. We suggest that protecting Stratiotes simultaneously conserves valuable arthropod fauna, including A. viridis. 相似文献
70.
This study consisted of sampling benthic algae at 32 sites in the Gangqu River, an important upstream tributary of the Yangtze
River. Our aims were to characterize the benthic algae communities and relationships with environmental variables. Among the
162 taxa observed, Achnanthes linearis and Achnanthes lanceolata var. elliptica were the dominant species (17.10% and 14.30% of the total relative abundance, respectively). Major gradients and principal
patterns of variation within the environmental variables were detected by principal component analysis (PCA). Then non-metric
multidimensional scaling (NMS) divided all the sites into three groups, which were validated by multi-response permutation
procedures (MRPP). Canonical correspondence analysis (CCA) indicated that three environmental variables (TN, TDS, and TP)
significantly affected the distribution of benthic algae. Weighted averaging regression and cross-calibration produced strong
models for predicting TN and TDS concentration, which enabled selection of algae taxa as potentially sensitive indicators
of certain TN and TDS levels: for TN, Achnanthes lanceolata, Achnanthes lanceolata var. elliptica, and Cymbella ventricosa var. semicircularis; for TDS, Cocconeis placentula, Cymbella alpina var. minuta, and Fragilaria virescens. The present study represents an early step in establishing baseline conditions. Further monitoring is suggested to gain
a better understanding of this region. 相似文献