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1.
Protected cultivation of ornamental flowers, as a commercial venture, becomes less profitable with excessive use of fertilizers. The present study examined the influence of microbial biofilm inoculants (Anabaena–Azotobacter, Anabaena–Trichoderma and Trichoderma–Azotobacter) on the availability of soil nutrients and structure of rhizosphere microbial communities in three varieties of chrysanthemum (var. White Star, Thai Chen Queen and Zembla). Varietal-specific responses in growth, enzyme activities, flower yield of plants and availability of soil nutrients were recorded. Dehydrogenase activity was highest in var. White Star treated with the Anabaena–Trichoderma biofilm inoculants. The Anabaena–Azotobacter inoculant enhanced the availability of nitrogen, phosphorus and micronutrients in the soil, besides 40–50% increase in soil organic carbon, as compared to carrier alone or no inoculation. PCR-DGGE profiling of the cyanobacterial communities and qPCR quantification of 16S rRNA abundance of bacteria, archaea and cyanobacteria in the rhizosphere soils, revealed the stronger influences of these inoculants, especially in var. Zembla. Principal Component Analysis (PCA) helped to illustrate that the enhanced microbe-mediated availability of soil macro-and micronutrients, except iron content (Fe), was the most influential factor facilitating improved plant growth and yield parameters. The Anabaena–Azotobacter, and Anabaena–Trichoderma biofilm inoculants, proved superior in all three chrysanthemum varieties. 相似文献
2.
Continental mapping of forest ecosystem functions reveals a high but unrealised potential for forest multifunctionality 下载免费PDF全文
《Ecology letters》2018,21(1):31-42
Humans require multiple services from ecosystems, but it is largely unknown whether trade‐offs between ecosystem functions prevent the realisation of high ecosystem multifunctionality across spatial scales. Here, we combined a comprehensive dataset (28 ecosystem functions measured on 209 forest plots) with a forest inventory dataset (105,316 plots) to extrapolate and map relationships between various ecosystem multifunctionality measures across Europe. These multifunctionality measures reflected different management objectives, related to timber production, climate regulation and biodiversity conservation/recreation. We found that trade‐offs among them were rare across Europe, at both local and continental scales. This suggests a high potential for ‘win‐win’ forest management strategies, where overall multifunctionality is maximised. However, across sites, multifunctionality was on average 45.8‐49.8% below maximum levels and not necessarily highest in protected areas. Therefore, using one of the most comprehensive assessments so far, our study suggests a high but largely unrealised potential for management to promote multifunctional forests. 相似文献
3.
Coral reef and reef-fish communities are complex systems that have spatial structures that are influenced by multiple factors and processes that interact at several scales. We analysed composition data of reef-fish communities in the Yucatan Peninsula fringing reef system using a hierarchical multi-scale survey design to elucidate the origins of the species distribution patterns through multivariate canonical ordination and partitioning analysis. Twelve reef sites were surveyed along the fringing reef system, nested in three sectors, each with distinctive human interests (tourism, fishing, protection). Line transects were placed on reef lagoon, reef front, reef slope and reef terrace habitat for a total of 480 transects. The communities were composed of many rare and some dominant species (e.g., Thalasoma bifasciatum, Acanthurus bahianus, A. coeruleus, Sparisoma aurofrenatum). Redundancy analyses revealed that environmental variables explained between 11% and 22% of the variation in fish community data according to the habitat analysed. Spatial variables, represented by the geographic coordinates of transects, explained a low percentage (2–5%) of variation in the fish community data. Among the environmental variables that significantly explained (P < 0.05) the patterns of variation on the fish community were depth, topographical complexity, and the percentage of the substratum covered by algae, calcareous floor, rock and rubble. Although the total explained variation and proportion of the variation explained by each set of variables were consistently low, most of the effects on the fish community composition data were significant. Explanations are proposed concerning those results. Evincing the distribution patterns on the biological systems of multi-species as well as the causes that shape them is key for conservation planning and essential in highly threatened regions, such as the Caribbean coast of the Yucatan Peninsula. 相似文献
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Local community participation and ex situ conservation has the potential to assist the recovery of the endangered Egyptian tortoise, Testudo kleinmanni. We initiated an in situ community‐based conservation and research program from a captive population of T. kleinmanni. We used a captive population of the Egyptian tortoise to train a member of the local community as a research technician and used his indigenous tracking skills and knowledge of the area to collect activity and dietary data on 28 captive tortoises. We overcame problems with illiteracy by creating a data sheet based on symbols and numbers. This data sheet allowed us to use the indigenous knowledge of various people from the community, and employ them in the future. Our local community approach to data collection, in conjunction with a craft program, made the conservation of the Egyptian tortoise more rewarding to the local community by providing a more sustainable form of income than collecting animals for the pet trade. Our multidimensional approach (local community participation as research technicians, craft program, and trust building) for gaining local support eventually led to the rediscovery of wild Egyptian tortoises in North Sinai, which was significant, as this species was presumed extinct in Egypt. We have now shifted our focus to in situ conservation, using the research and local capacity building template developed from this captive population study. Our template can be used by zoos and conservation organizations with small budgets and collections of native species in natural habitats to create similar captive research programs that can be applied to in situ conservation. Zoo Biol 26:397–406, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
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Kristjan Zobel 《Evolutionary ecology》2008,22(3):487-492
Although sexuality is considered evolutionarily progressive, clonality is very common in plants and the prevailing means of
reproduction in several community types. I discuss what could be the forces that have influenced the selection among sexual
versus non-sexual reproduction at community level. I propose that, among others, the probability of self-competition must
have been one of the key factors. The probability of meeting one’s own genes for wasteful competition is higher in communities
where clonality prevails (and relatively high mean intra-species relatedness is expected), and higher in communities with
low species diversity. On the other hand, lower diversity indicates a higher average fitness of species since the (finite)
total pool of resources is distributed among fewer population with high density. I show, using four community types with contrasting
diversity and clonality that community fitness (average fitness in the assemblage of species) can be expressed as the product
of two variables––anti-diversity and degree of sexuality. 相似文献
8.
E. Balátová-Tuláčková 《Plant Ecology》1985,59(1-3):111-117
Forty Molinietalia communities were analyzed from the phytogeographical point of view in order to establish their distribution tendencies in Czechoslovakia in relation to the floristic regions of Hercynicum, Pannonicum and Carpaticum. Only few moist meadow communities of the Molinietalia order are found in the whole area under study; most of them have their distribution center in one of the floristic regions mentioned above. Eleven Calthion and two Molinion associations are confined to the Hercynicum, eight of them strictly. It is only in the Moravian and Slovak Pannonicum that all associations of the alliances Cnidion venosi and Veronico longifoliae-Lysimachion occur; they appear there together with two Molinion communities, the distribution of which is, however, a little wider. Three Calthenion communities show a still wider distribution, extending into the adjoining areas. One Calthenion community occurs in the Bohemian Pannonicum and its surroundings, two Calthenion associations have their distribution center in the Carpaticum, but they are not strictly confined to it.The author wants to express her thanks to Doc. Dr Miroslav Smejkal, CSc., for critical revision of the text. 相似文献
9.
James B. Waldram 《Human ecology: an interdisciplinary journal》1987,15(2):117-131
The relocation and consolidation of subarctic native populations into settlement patterns designed according to southern, urban models has often resulted in cultural confusion and an increase in interpersonal tension, alcohol abuse, and violence. Through a review of selected case material, and the detailed examination of one relocated community, the dynamics of this situation are highlighted. Where native communities have re-established themselves beyond the reach of government planners, the recreation of more culturally appropriate settlement patterns has ensued. 相似文献
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