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71.
Habitat Conservation Plans (HCPs) under the Endangered Species Act (ESA) are an important mechanism for the acquisition of land and the management of terrestrial and aquatic ecosystems. HCPs have become a vital means of protecting endangered and threatened species and their habitats throughout the United States, particularly on private land. The scientific consensus that climate is changing and that these changes will impact the viability of species has not been incorporated into the conservation strategies of recent HCPs, rendering plans vulnerable biologically. In this paper we review the regulatory context for incorporating climate change into HCPs and analyze the extent to which climate change is linked to management actions in a subset of large HCPs. We conclude that most current plans do not incorporate climate change into conservation actions, and so we provide recommendations for integrating climate change into the process of HCP development and implementation. These recommendations are distilled from the published literature as well as the practice of conservation planning and are structured to the specific needs of HCP development and implementation. We offer nine recommendations for integrating climate change into the HCP process: (1) identify species at-risk from climate change, (2) explore new strategies for reserve design, (3) increase emphasis on corridors, linkages, and connectivity, (4) develop anticipatory adaptation measures, (5) manage for diversity, (6) consider assisted migration, (7) include climate change in scenarios of water management, (8) develop future-oriented management actions, and (9) increase linkages between the conservation strategy and adaptive management/monitoring programs.  相似文献   
72.
Mechanochemistry, a technique concerning with milling contaminated samples for prolonged times, induces massive degradation of pollutants by grinding them in ball mills with different soil components or additives. In the present study, laboratory experiments were conducted to evaluate the effect of aging on the mechanochemical efficiency of the Mn-oxide birnessite in degrading pentachlorophenol (PCP). A comparative study on an aged birnessite (KBiA), used after 3 years from synthesis, and a fresh birnessite (KBiF), employed immediately after synthesis, was carried out. The differences between the two birnessites, evidenced by spectroscopic and diffractometric techniques, are mainly relative to reduction of the Mn(IV) centered at the MnO6 octahedra layers from the birnessite structure, which represent the most reactive sites for PCP degradation. The long term air drying at room temperature, by favouring reduction of Mn(IV) to Mn(III), produces an inorganic substrate that offers paucity of the less reactive sites for PCP degradation, thus reducing the oxidative potential of the KBiA. Accordingly, the more reactive fresh birnessite was employed in the experiment with a polluted soil. Adding a small amount of KBiF to soil only induces a light increase in PCP removal, probably due to the mechanically induced PCP adsorption and transformation onto clay minerals present in the soil. Besides, adding a higher dose of birnessite causes a stronger degradation of PCP.  相似文献   
73.
Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed.Notable SO2 and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO2’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO2 was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO2 generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.  相似文献   
74.
Animal wastes from intensive pig farming as fertilizers may expose crops to antimicrobials. Zea mays cultivations were carried out on a virgin field, subjected to dressing with pig slurries contaminated at 15 mg L−1 of Oxy- and 5 mg L−1 of Chlor-tetracycline, and at 8 mg L−1 of Oxy and 3 mg L−1 of Chlor, respectively. Pot cultivation was performed outdoor (Oxy in the range 62.5-1000 ng g−1 dry soil) and plants harvested after 45 days. Tetracyclines analyses on soils and on field plants (roots, stalks, and leaves) did not determine the appreciable presence of tetracyclines. Residues were found in the 45-day pot corn only, in the range of 1-50 ng g−1 for Oxy in roots, accounting for a 5% carry-over rate, on average. Although no detectable residues in plants from on land cultivations, both experimental batches showed the same biphasic growth form corresponding to a dose/response hormetic curve.  相似文献   
75.
We built a trophic network based on a matrix of interspecific trophic relationships to assess the role of elasmobranch fishes in shaping community structure of the Gulf of Tortugas in the Colombian Pacific Ocean. We analyzed diet similarities to define trophic components (nodes) - rather than taxonomical groups - in the network. We evaluated the ecological function of species or trophic entities through topological analysis of their structural importance in trophic networks by applying one local and several mesoscale network indices. We found that top predatory elasmobranchs play an important ecological role in top-down control and in propagating indirect effects through the system owing to high values of the node degree, centrality and topological importance indices. However, invertebrates and teleost fishes had higher connectivity and topological importance than other elasmobranchs in the network before and after removal of top predators from the system. Results from our study thus suggest that elasmobranchs at intermediate trophic levels - commonly referred to as “mesopredators” - are not so important in all complex coastal ecosystems as previously reported.  相似文献   
76.
77.
Rockfalls are a common type of fast-moving slope failures, and in many countries they represent the primary cause of landslide fatalities. We present a methodology to ascertain rockfall hazard and to determine the associated risk along transportation networks. The proposed methodology is based on the combined analysis of the recurrence of rockfall events, determined from historical information, the frequency-volume statistics of rockfalls, obtained from inventories of recent rockfall triggering events, and the results of a physically based, spatially distributed rockfall simulation model used to determine rockfall hazard. The available information on rockfall hazard is combined in a Geographic Information System with a map of the transportation network to identify the road sections potentially subject to rockfalls. Information on the location and type of rockfall defensive measures, including revetment nets, elastic fences, concrete walls, and artificial tunnels, is used to estimate the efficacy of the defensive structures and to determine the level of the residual rockfall risk along the roads. To illustrate the methodology, we discuss an application in a 48-km2 area in the Nera River valley, in the Umbria Region of central Italy, where rockfalls are abundant, and where considerable investments were recently made to mitigate rockfall risk. Note: This version was published online in June 2005 with the cover date of August 2004.  相似文献   
78.
We propose a new approach to evaluate the natural attenuation capacity of soil by using fluorescence in situ hybridization (FISH). A specific oligonucleotide probe AtzB1 was designed based on the sequence data of the atzB gene involved in the hydrolytic deamination of s-triazines; this gene, located in a multiple copy plasmid was detected by the optimized FISH protocol. Two agricultural soils (Lodi and Henares) with a history of simazine treatments, and two natural soils (Soto and Monza), without previous exposure to simazine, were studied. AtzB1 probe-target cells were found only in the agricultural soils and, in a greater percentage, in the Lodi soil, compared to the Henares one. Moreover, the greatest percentage of AtzB1 probe-target cells in Lodi was accompanied by a greater mineralization rate, compared to the Henares soil. The FISH method used in this study was suitable for the detection of simazine-degrading bacteria and could be a useful indicator of the potential of soil bioremediation.  相似文献   
79.
The mercury content has been determined in samples of fumarolic gases, phreatic waters, soil and vegetation collected at Vulcano, Aeolian Islands, Italy. Volcanic activity is demonstrated as a source of natural mercury pollution whose extent has been evaluated here by studying the contribution of different components of the surface environment. The possible influences for living organisms are examined.  相似文献   
80.
The Mar Piccolo of Taranto, classified as a ‘Site of National Interest’ (SIN), is a semi-enclosed basin divided into two inlets with lagoon features and sea influences, seriously affected by anthropic activities. In the framework of the RITMARE project, a study has been carried out to evaluate the functionality of this ecosystem. As part of this work, measurements of the water abiotic parameters were performed in order to assess the physical–chemical features of this area after the activation, in the last decade, of treatment plants for various urban and industrial dumping. Seawater intrusions and continental inputs, as well as several submarine freshwater springs, clearly affect physical–chemical characteristics of the water column in the two inlets. This finding suggests that small-scale patterns in water circulation have the potential to influence the chemical properties of the seawater. The comparison with a 20-year dataset reveals a drastic decrease in nutrient concentrations after the year 2000, validating the functionality of the treatment plants. The reduction of nutrient inputs into the basin (up to ?90 % in the first inlet characterized by lower hydraulic residence time) has changed the biogeochemical characteristics of the Mar Piccolo from being relatively eutrophic to moderately oligotrophic.  相似文献   
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