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The effects of three cultivars, two water regimes and two rates of applying nitrogen fertilisers were tested when studying the performance of rice (Oryza sativa L.) near to, and distant from, a fertiliser plant emitting atmospherically dispersed pollutants. The atmosphere near the fertiliser plant had average daily peak concentrations of 144 and 210 microg m(-3) of SO(2) and NO(2), respectively. Growth was less near to, than at a distance from, the fertiliser plant. On average it was decreased by water stress while the effects of different amounts of nitrogen fertiliser were variable. Whilst there were a number of interactions involving nitrogen and water treatments, the most consistent were associated with the responses of the three cultivars at the two locations. The three cultivars performed similarly at the unpolluted control site, but there were major differences at the polluted site. These were most clearly exemplified by changes in the proportion of dry matter allocated to yields of grain and straw. At the unpolluted site, grain accounted for about 30% of the combined yields of grain and straw. At the polluted site, grain accounted for 1, 23 and 31% of the combined grain and straw yields of cultivars CO 43 (the most sensitive), TKM 9 and GR 3 (the most tolerant). Grain yields were closely related to numbers of filled grains per plant. At the polluted site, 98% of grains failed to develop in CO 43, whereas in GR 3, the number of panicles, and therefore the potential number of grains, was significantly enhanced.  相似文献   
2.
Sacred natural sites (SNS) are instances of biocultural landscapes protected for spiritual motives. These sites frequently host important biological values in areas of Asia and Africa, where traditional resource management is still upheld by local communities. In contrast, the biodiversity value of SNS has hardly been quantitatively tested in Western contexts, where customs and traditions have relatively lost importance due to modernization and secularization. To assess whether SNS in Western contexts retain value for biodiversity, we studied plant species composition at 30 SNS in Central Italy and compared them with a paired set of similar but not sacred reference sites. We demonstrate that SNS are important for conserving stands of large trees and habitat heterogeneity across different land-cover types. Further, SNS harbor higher plant species richness and a more valuable plant species pool, and significantly contribute to diversity at the landscape scale. We suggest that these patterns are related not only to pre-existent features, but also to traditional management. Conservation of SNS should take into account these specificities, and their cultural as well as biological values, by supporting the continuation of traditional management practices.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0738-5) contains supplementary material, which is available to authorized users.  相似文献   
3.
Oryza sativa L. cv. GR3 was grown near to a fertilizer plant and the growth of its seed progeny was evaluated at sites near to, and distant from, the fertilizer plant. The grain yield was reduced in plants grown at the polluted site, with reduced panicle length and increased sterility index. This decrease in grain yield was higher in the progeny plants than in the normal polluted plants. The polluted progeny grown at a control site showed a normal yield, but an increased sterility index. Accumulation of total sulphur and fluoride was higher in the leaves of polluted rice plants. It was evident that tolerance to air pollution was reduced in the progeny plants due to an additional dosage of sulphur and fluoride pollutants and to unfavourable climatic factors. Further, pollution effects were not carried over in progeny plants when grown in an unpolluted environment.  相似文献   
4.
A key obstacle to conservation success is the tendency of conservation professionals to tackle each challenge individually rather than collectively and in context. We sought to prioritize barriers to conservation previously described in the conservation literature. We undertook an online survey of 154 practitioners from over 70 countries to ascertain the most important barriers to conservation they faced. We used statistical analyses to identify the key impediments to conservation success and to examine whether these were affected by organizational attributes. Twenty-one barriers were identified. The importance ascribed to those was influenced by continent of operation and organization size, but not by organization age or autonomy (from larger parent organizations). We found the most important barriers to consider when undertaking conservation action were wider issues (e.g., population growth, consumerism, favoring development, and industrial-scale activity), operating environment (e.g., lack of political will, ineffective law enforcement, weak governments, corruption, safety and security), community attributes (e.g., dynamics, conflicts, and education levels), and the way conservation is undertaken (overconfidence, lack of funding, and externally set agendas). However, we advise against applying a one-size-fits-all approach. We propose that conservationists account for the complex socioecological systems they operate in if they are to achieve success.  相似文献   
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