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Taxus baccata L. has a scattered distribution and the decline of yew woodlands is observed across the entire species range. Passively protected populations in the central and northern part of their distribution are declining without human intervention. However, the establishment of new yew populations is observed in habitats that have been significantly transformed by humans. The following question need to be answered: why do yews find better in environmental conditions that have been strongly modified by humans compared to natural systems? The Quaternary history might be the key to understand the current yew situation. As suggested by palaeobotanical studies, pollen of T. baccata was observed at optima of the interglacials, but in subsequent periods, it has been displaced by that of other shade-tolerant species. Pollen diagrams indicate that after the last glaciation, the yew did not appear earlier than other shade-tolerant species and did not have the opportunity to become common in occurrence, as in previous interglacial periods. As a result, yews occur only as relict populations within environmental islands where the competition with other shade-tolerant species is low. The negative human impact on yew is well-documented, but limitations resulting from the biology of this species are also very important. T. baccata is a species whose current scattered distribution may explain the Quaternary history. Yew situation is better in artificial conditions because people reduce competition from other trees species and deer pressure. Possible positive impact of human on yew distribution in the past is also discussed. The current biological condition of this species suggests the need for active protection.
Environmental sustainability is currently a topical issue globally. Reason for this might not be unconnected with the need to ensure balancing of environmental protection as well as social responsibility as requisite for healthy environment and economy. Thus, an understanding of the indispensability of environment generally has led to the clarion call for better steward of environment by human beings, bearing in mind the deteriorating state of the environment and its consequences. This study employed a triangulation of instrument in developing responsible attitude towards environment. 72 participants involving artisans, technocrats, farmers, marketers, industrialists, public servants and institutions were drawn across urban and peri-urban areas within four local governments in Oyo, Oyo state, Nigeria. In-depth interviews were conducted among the participants on the extent, effects of human impacts as well as desirability of responsible attitudes to the environment. Data were analyzed through coded description, verbatim reporting, content analysis and categorization of ideas expressed by participants in the IDIs. It was revealed that human beings have impacted on the environment in a number of ways culminating in untold effects on the environment and its components. The need for responsible attitude to environment was therefore suggested as measure towards sustainable environment and development.
Land-inland water ecotones are environments of exceptional diversity, but are also highly vulnerable to impacts from human settlement. Settlement on floodplains and exacerbation of peak runoff from land-use changes have resulted in flood damage to human structures, leading in reaction to widespread efforts to control flooding through such measures as land drainage and construction of levees and artificial flood control channels. These measures increase flood hazard downstream and result in loss of valuable riparian and aquatic habitats. Similarly, human settlements along river banks may be threatened by natural channel migration, leading to ill-conceived bank stabilization projects, which eliminate riparian habitat. Environmental planning strategies to minimize these impacts include reducing stormwater runoff through use of permeable pavement, infiltration galleries, and detention basins; ordinances protecting urban streams and riparian corridors (from development, filling, etc.); prohibitions or restrictions on development on floodplains; retention of vegetative buffer strips along stream channels; maintenance of continuity of riparian corridors for wildlife and human use; use of alternatives to traditional flood control strategies; and release of flushing flows to mimic effects of natural floods below reservoirs.
Paper presents a scale of hemeroby of 86 plant communities constituting the vegetation cover of Szczecin (northwestern Poland), studied in the years 1999–2002. The applied nine-grade hemeroby scale expresses the anthropogenic transformation of habitats and enables the presentation of the vegetation resilience to human impact. The hemeroby spectrum of the analysed syntaxa differs from one grade in case of highly specialised communities (either semi-natural or synanthropic, like Typhetum latifoliae and Eragrostio-Polygonetum) to six grades – for communities found both on semi-natural and highly modified habitats, usually occupying eutrophic biotopes (like Urtico-Calystegietum and UrticoAegopodietum).
Thirty-one metals and fifteen PAHs were examined in soils of central Spitsbergen, high Arctic. One of the world's northernmost human settlements and natural tundra were sampled to estimate the local human impact and its range. The contamination caused by local sources is significant only in the closest vicinity, and is usually at least an order of magnitude lower than European limits. The metal concentrations are closely related to bedrock geology and they are at similar levels as elsewhere in Svalbard. The long-dis­tance transport of contaminants was not found at a significant level.
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