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61.
62.
We report observations of disappearance of Erica tetralix in wet heathland, which is unlikely to be caused by competition, as E. tetralix is dying before its place is taken up by other species. To investigate the causes, we used both old and new data. Results showed that presence of Molinia caerulea and Calluna vulgaris were substantial in the former E. tetralix dominated areas. Measurements of the C/N ratio in the morlayer were between 21 and 26 under the E. tetralix stands. As the expected C/N ratio in a healthy nutrient poor ecosystem like the E. tetralix wet heathland is around 30, this indicates that the ratio is probably decreasing and, correspondingly, the probability of nitrogen leaching from the ecosystem is increasing. The morlayer pH was extremely low—between 3.03 and 3.78. This represents a pH decline since the 1960s, where pH values generally were above 4. This supports the hypothesis that the decrease in morlayer pH is the major factor explaining the disappearance of E. tetralix and that measures to increase pH should be considered as part of the recommendations for relevant future management.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-012-0251-z) contains supplementary material, which is available to authorized users. 相似文献63.
André Bélanger Charles Vincent Domingos de Oliveira 《Journal of environmental science and health. Part. B》2013,48(5):615-625
Abstract In 1986 strawberry plots were treated with dimethoate, malathion, permethrin and cypermethrin at 80% bloom of primary flowers. In 1987 the plots were sprayed with dimethoate, malathion and permethrin at 30% bloom. Residue analysis of these insecticides on the flowers were analyzed using solvent extraction and gas liquid chromatography. Residue analysis at 0 to 18 days on flowers and fruit showed an exponential decrease. Organophosphates tended to degrade more quickly than synthetic pyrethroids. The results are discussed in the context of an integrated pest management program. 相似文献
64.
浅谈建筑施工噪声的网络化管理 总被引:2,自引:0,他引:2
通过《南宁市环境信息综合管理系统》中建筑施工噪声管理子系统的重点研究和建设,对建设施工项目审批、中午夜间施工许可登记及施工噪声投诉实时监控,加强监督,改善了管理环节,提高了管理效能,取得了良好的效果。 相似文献
65.
Severe drinking water shortage affects all resident of the Kabul river basin. Two and a half decades of civil war in Afghanistan
(it began in late 1978) have resulted in widespread environmental degradation and water resource development throughout the
country. The war has already finished and, therefore, water resource management for supplying water is one of the most important
tasks for Afghanistan’s government. The Kabul river basin which is the most populated area in the country is located in the
eastern part of Afghanistan. This article deals with the water resource properties of the Kabul river basin and also water
demand in the important cities of the basin, such as Kabul, the capital and the largest city in the country. Also a few suggestions
for providing water for domestic and agriculture purposes in short term, medium time and long term have been discussed. 相似文献
66.
It is well established that trees help to reduce air pollution, and there is a growing impetus for green belt expansion in urban areas. Identification of suitable plant species for green belts is very important. In the present study, the Air Pollution Tolerance Index (APTI) of many plant species has been evaluated by analyzing important biochemical parameters. The Anticipated Performance Index (API) of these plant species was also calculated by considering their APTI values together with other socio-economic and biological parameters. Based on these two indices, the most suitable plant species for green belt development in urban areas were identified and recommended for long-term air pollution management. 相似文献
67.
On-farm water storages (locally known as farm dams or farm ponds) are an important part of many agricultural landscapes, as
they provide a reliable source of water for irrigation and stock. Although these waterbodies are artificially constructed
and morphologically simple, there is increasing interest in their potential role as habitat for native flora and fauna. In
this article, we present results from a case study which examined the habitat characteristics (such as water physical and
chemical parameters, benthic metabolism, and macrophyte cover) and the macrophyte and macroinvertebrate biodiversity of eight
farm ponds on four properties in the Stanley Catchment, Southeast Queensland, Australia. Each landowner was interviewed to
allow a comparison of the management of the ponds with measured habitat and biodiversity characteristics, and to understand
landowners’ motivations in making farm pond management decisions.
The physical and chemical water characteristics of the study ponds were comparable to the limited number of Australian farm
ponds described in published literature. Littoral zones supported forty-five macroinvertebrate families, with most belonging
to the orders Hemiptera, Coleoptera, Odonata, and Diptera. Invertebrate community composition was strongly influenced by littoral
zone macrophyte structure, with significant differences between ponds with high macrophyte cover compared to those with bare
littoral zones. The importance of littoral zone macrophytes was also suggested by a significant positive relationship between
invertebrate taxonomic richness and macrophyte cover.
The landowners in this study demonstrated sound ecological knowledge of their farm ponds, but many had not previously acknowledged
them as having high habitat value for native flora and fauna. If managed for aquatic organisms as well as reliable water sources,
these artificial habitats may help to maintain regional biodiversity, particularly given the large number of farm ponds across
the landscape. 相似文献
68.
In dune slacks in The Netherlands, a decline of rare mesotrophic basiphilous plant species and their plant communities has
been observed in combination with an increase of more productive systems with common, taller acidophilous plant species. This
has been attributed to both natural and anthropogenic changes. In a humid climate with a precipitation surplus, as in The
Netherlands, the calcium carbonate content of a calcareous soil increases with depth. However, soils in coastal dune slacks,
may have a higher carbonate content in the topsoil horizon than in the underlying layers. Carbonates which buffer the pH can
prolong the presence of mesotrophic basiphilous plant communities which are of high conservation value.
To explain the occurrence of calcareous surface horizons in dune slacks, hydrological and micromorphological analyses were
carried out in three dune slacks. Two slacks are situated on the Wadden Sea islands in the northern part of The Netherlands;
one on Schiermonnikoog and one on Texel. The third slack is situated in the dunes on the island of Goeree in the southwestern
part of The Netherlands. In all three slacks, carbonate occurs as mollusc and gastropod fragments (silt- or sand-sized) and
as micritic nodules in the topsoil layer, due to aeolian deposition and sedimentation by water.In situ carbonate accumulation (calcitans and calcareous crusts) due to CO2 release in inundated and/or capillary rise of calcareous groundwater near, or at the soil surface. Accumulation of carbonate
also occurs as a result of biological activity by algae in the topsoil of the Goeree site. In general, hydrological processes
maintaining high levels of calcareous groundwater are a prerequisite for the maintenance of high carbonate levels in topsoils.
Such levels are necessary for the conservation and management of basiphilous pioneer vegetation. 相似文献
69.
Dickella Gamaralalage Jagath Premakumara Aloysius Mariae L. Canete Masaya Nagaishi Tonni Agustiono Kurniawan 《Waste management (New York, N.Y.)》2014,34(6):971-979
Municipal Solid Waste Management (MSWM) is considered to be one of the most serious environmental issues in the Philippines. The annual waste generation was estimated at 10.6 million tonnes in 2012 and this is expected to double in 2025. The Republic Act (RA) No. 9003, widely known as the Ecological Solid Waste Management Act of 2000, provides the required policy framework, institutional mechanisms and mandate to the Local Government Units (LGUs) to achieve 25% waste reduction target through establishing an integrated solid waste management plan based on the 3Rs (reduce, reuse and recycling). Although the initial impact of the LGUs is still very limited in implementing the national mandate, this article highlights the successful experiences of Cebu, the second largest city in the Philippines, in reducing its MSW generation by more than 30% in the past three years. This study also explores the implementation process, innovative actions taken by the Cebu City Government in implementing the national mandate at local level and identifies the factors that influence the policy implementation. The findings suggest that the impacts of the national mandate can be achieved if the LGUs have the high degree of political commitment, planning and development of effective local strategies in a collaborative manner to meet with local conditions, partnership building with other stakeholders, capacity development, adequate financing and incentives, and in the close monitoring and evaluation of performance. 相似文献
70.
R. Gamberini D. Del Buono F. Lolli B. Rimini 《Waste management (New York, N.Y.)》2013,33(11):2532-2540
The definition and utilisation of engineering indexes in the field of Municipal Solid Waste Management (MSWM) is an issue of interest for technicians and scientists, which is widely discussed in literature. Specifically, the availability of consolidated engineering indexes is useful when new waste collection services are designed, along with when their performance is evaluated after a warm-up period. However, most published works in the field of MSWM complete their study with an analysis of isolated case studies. Conversely, decision makers require tools for information collection and exchange in order to trace the trends of these engineering indexes in large experiments. In this paper, common engineering indexes are presented and their values analysed in virtuous Italian communities, with the aim of contributing to the creation of a useful database whose data could be used during experiments, by indicating examples of MSWM demand profiles and the costs required to manage them. 相似文献