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31.
Lopes C Herva M Franco-Uría A Roca E 《Environmental science and pollution research international》2011,18(6):918-939
Background, aim, and scope
In this work, an environmental risk assessment of reusing organic waste of differing origins and raw materials as agricultural fertilizers was carried out. An inventory of the heavy metal content in different organic wastes (i.e., compost, sludge, or manure) from more than 80 studies at different locations worldwide is presented. 相似文献32.
Mother really knows best: host choice of adult phytophagous insect females reflects a within-host variation in suitability as larval food 总被引:1,自引:0,他引:1
Anders Wennström Lena Niemi Hjulström Joakim Hjältén Riitta Julkunen-Tiitto 《Chemoecology》2010,20(1):35-42
Non-random distribution patterns of specialized phytophagous insects on their hosts may depend on intraspecific differences
in plant tissue quality, including nutrients and secondary compounds. Secondary compounds are involved in plant resistance,
but are also important for the recognition and acceptability of plants as resources by specialized insects. If individuals
within a plant species vary in their content of such secondary substances, there may also be qualitative differences between
them. In such cases, natural selection will favor insects with the ability to distinguish and prefer the more suitable plants.
In Sweden, the leaf beetle Gonioctena linnaeana Schrank (Coleoptera, Chrysomelidae) is highly specialized on one host, the native willow Salix triandra L (Salicaceae). Field observations reveal that some host plants in a population harbor many feeding larvae, causing severe
defoliation, whereas neighboring plants may have few or no feeding larvae. Our hypothesis is that the distribution pattern
of G. linnaeana larvae in this population results from qualitative differences between individual host plants in combination with the ability
of G. linnaeana females to distinguish between plants that are suitable and not suitable for offspring performance. We examine whether larval
survival differs depending on diet and whether the content of secondary chemical compounds explains female preference. Based
on the higher survival rate of larvae reared on leaves from preferred hosts, we conclude that G. linnaeana females have evolved a behavior that maximizes offspring performance and thus positively affects female fitness. A chemical
survey of the plants indicates that luteolin-7-glucoside and an unidentified flavonoid are important for separating the preferred
from the non-preferred plants. 相似文献
33.
Coniferous trees of different species, or of the same species growing at different locations, vary in the extent to which they are attacked by various herbivores and pathogens. Plant secondary metabolites might be a key to understanding some of this variation. At the site level, we investigated if there was an intra- or interspecies pattern for individual compounds (or for groups of compounds) and their relationship to indices of plant nitrogen and plant productivity. For example, do plants exhibit similar covariance in defence compounds when evaluated across a number of sites varying in productivity? Here, we concentrated on the phenolic profile of Pinus sylvestris, Picea abies, Juniperus communis and Pinus contorta. Our results indicate striking differences in secondary chemistry profiles of the twigs including needles of the trees and in the inter-relationships amongst individual compounds and groups of compounds. Flavonols occurred in high variety in P. sylvestris and were highly correlated with each other, differing from P. contorta. But the results of the factor analyses indicate an underlying pattern for flavonols of the coumaroyl type for P. contorta. In contrast, the compounds of the other tree species showed a low degree of inter-correlation. Co-occurring phenolics of different tree species were not correlated. Overall, our analysis of site indices indicated that plant productivity was not a useful predictor for the concentration of specific phenolics. The relationship amongst plant nitrogen and specific phenolics might be the result of two defence strategies (one related and the other not related to nitrogen content). This might enable the plant to shift its defences against attacks with a high degree of flexibility. 相似文献
34.
Liisa Huttunen Pekka Niemelä Riitta Julkunen-Tiitto Susanne Heiska Riitta Tegelberg Matti Rousi Seppo Kellomäki 《Chemoecology》2008,18(2):85-98
Summary. We examined the effects of defoliation con-currently with elevated temperature and CO2 on some chemical and morphological characteristics in the leaves of silver birch seedlings (Betula pendula). We also analyzed the consequent changes in the palatability of leaves for adult blue alder leaf beetles (Agelastica alni). Under the different climatic treatments, the seedlings were subjected to three fertilizer treatments (0 kg, 130 kg and
270 kg N ha−1) and defoliation treatments (0%, 25% and 50% of the total leaf area). In each climatic treatment, fertilization increased
the nitrogen content in the leaves, but decreased total concentrations of soluble phenolics, detected by high-performance
liquid chromatography (HPLC), and insoluble condensed tannins. Defoliation, both independently and in combination with elevated
temperature and CO2, decreased the concentrations of the phenolics. Compared to the intact controls, the leaves of the defoliated seedlings were
smaller and tougher. Under elevated temperature, the beetles consumed a smaller amount of the leaves of plants subjected to
the high fertilization, while under ambient climatic conditions, fertilization increased the feeding. The total leaf consumption
was higher under the ambient climatic conditions than under elevated temperature, elevated CO2 or the combination of elevated temperature and CO2. 相似文献
35.
Markus Porthin Tony Rosqvist Adriaan Perrels Riitta Molarius 《Regional Environmental Change》2013,13(6):1171-1180
Decision-making for the purpose of adaptation to climate change typically involves multiple stakeholders, regions and sectors as well as multiple objectives related to the use of resources and perceived benefits. Standard cost–benefit analysis can be argued to take into account easily monetised effects only. Multi-criteria decision analysis (MCDA) embedded in participatory processes can therefore play an important role in defining the decision context and exploring stakeholders’ preferences. In this paper, a case study on flood protection of the Kokemäki river running through the city of Pori in West Finland was conducted. The study was realised as a MCDA workshop involving the key stakeholders of the region. The analysis produced a robust ranking of the considered flood protection alternatives. According to the stakeholders, the approach was useful as an exploratory way of gaining a deeper and shared understanding of the flood protection. It was shown that MCDA is well suited for decision-making in adaptation to climate change–enhanced extreme events. 相似文献