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Telecare is often regarded as a win/win solution to the growing problem of meeting the care needs of an ageing population. In this paper we call attention to some of the ways in which telecare is not a win/win solution but rather aggravates many of the long‐standing ethical tensions that surround the care of the elderly. It may reduce the call on carers' time and energy by automating some aspects of care, particularly daily monitoring. This can release carers for other caring activities. On the other hand, remote and impersonal monitoring seems to fall short of providing care. Monitoring may be used to help elderly users retain independence. But it may also increase the amount of information which flows from users to carers, which can result in a form of function‐creep that actually undermines independence. 相似文献
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HEATHER KEITH BRENDAN MACKEY SANDRA BERRY DAVID LINDENMAYER PHILIP GIBBONS 《Global Change Biology》2010,16(11):2971-2989
Evaluating contributions of forest ecosystems to climate change mitigation requires well‐calibrated carbon cycle models with quantified baseline carbon stocks. An appropriate baseline for carbon accounting of natural forests at landscape scales is carbon carrying capacity (CCC); defined as the mass of carbon stored in an ecosystem under prevailing environmental conditions and natural disturbance regimes but excluding anthropogenic disturbance. Carbon models require empirical measurements for input and calibration, such as net primary production (NPP) and total ecosystem carbon stock (equivalent to CCC at equilibrium). We sought to improve model calibration by addressing three sources of errors that cause uncertainty in carbon accounting across heterogeneous landscapes: (1) data‐model representation, (2) data‐object representation, (3) up‐scaling. We derived spatially explicit empirical models based on environmental variables across landscape scales to estimate NPP (based on a synthesis of global site data of NPP and gross primary productivity, n=27), and CCC (based on site data of carbon stocks in natural eucalypt forests of southeast Australia, n=284). The models significantly improved predictions, each accounting for 51% of the variance. Our methods to reduce uncertainty in baseline carbon stocks, such as using appropriate calibration data from sites with minimal human disturbance, measurements of large trees and incorporating environmental variability across the landscape, have generic application to other regions and ecosystem types. These analyses resulted in forest CCC in southeast Australia (mean total biomass of 360 t C ha?1, with cool moist temperate forests up to 1000 t C ha?1) that are larger than estimates from other national and international (average biome 202 t C ha?1) carbon accounting systems. Reducing uncertainty in estimates of carbon stocks in natural forests is important to allow accurate accounting for losses of carbon due to human activities and sequestration of carbon by forest growth. 相似文献
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While the abundance of some plant species decreases under high grazing intensity, others become more abundant. Release from competition by decreaser species contributes to this pattern in mesic systems, but this may not be the case in xeric systems where competition may be less intense. Here we examine three mechanisms that may be involved: (i) increased recruitment and growth because of soil changes produced by grazing, for example, increased soil nutrient availability through dung accumulation; (ii) increased recruitment favoured by the breaking up of the lichen crust; and (iii) reduced competition because of the decline of decreaser species. We used field and glasshouse experiments to determine the possible contribution of these mechanisms to the increase of the chenopod Maireana pyramidata around a watering point in a chenopod shrubland of South Australia. There was no evidence of nutrient accumulation close to the watering point, and while seedlings of M. pyramidata responded to nutrient addition, their growth was the same in soil collected from areas with different grazing intensity. While a broken lichen crust increased the emergence of both M. pyramidata and the decreaser Atriplex vesicaria, the effect was larger for the former. We found no competition between seedlings of the two species or between juveniles of A. vesicaria and seedlings of M. pyramidata in glasshouse experiments. Adult plants of both A. vesicaria and M. pyramidata produced similar growth reduction in seedlings of M. pyramidata. Furthermore, a field removal experiment failed to detect any competitive effect of A. vesicaria on M. pyramidata. Our data indicate that the disintegration of the soil crust by grazer activities can be a major factor controlling floristic changes in overgrazed rangelands. These results imply that factors that control establishment may be more important than competition in shaping shrub population dynamics in these systems. Ground surface itself can affect establishment opportunities, and this should be taken into account in management and restoration efforts in arid lands. 相似文献
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MATTHEW J. BUTLER WARREN B. BALLARD R. DOUGLAS HOLT HEATHER A. WHITLAW 《The Journal of wildlife management》2010,74(5):1160-1162
ABSTRACT Wildlife managers traditionally monitored lesser prairie-chicken (Tympanuchus pallidicinctus) populations using road-based lek surveys and assumed booming can be heard ≥1.6 km from a lek. To assess this assumption, we measured sound intensity (decibels) of booming lesser prairie-chickens. Our results indicated sound intensity 1.6 km from a lek would be less than or equal to the sound intensity of a whisper. Thus, 1.6 km is probably too great a distance for audible detection of booming in many conditions. 相似文献
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