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851.
Abdelnaser?OmranEmail author Mahmoud?Altawati Georgina?Davis 《Environment, Development and Sustainability》2018,20(4):1597-1613
In Libya, municipal solid waste management is one of the services provided by the authorities to keep the county clean. This study was conducted in the City of Al-Bayda, located in the eastern part of Libya, as there have been several major problems facing the city in dealing with solid waste management. One of these problems is the generation, collection, handling, transportation, recycling, and disposal of municipal solid waste (MSW). This study has identified that the ongoing disposal of MSW to poorly engineered “dump sites” on the outskirts of the city is unsustainable and will not meet the demands of the growing population and increasing urbanization currently experienced within Al-Bayda. Factors impacting the decision-making and operational processes of MSW include lack of resources and services that significantly affect the disposal of waste, an inadequate number of waste collection containers making the distance to these containers for many households excessive, and thus leading to an increasing likelihood of dumping solid waste in open areas and roadsides. The study recommends that the city government of Al-Bayda should identify synergies and increase partnership-working arrangements with the private sector to ensure efficient management of MSW within the city area. 相似文献
852.
Oliver?TaherzadehEmail authorView authors OrcID profile Peter?Howley 《Environment, Development and Sustainability》2018,20(4):1807-1830
Market-based instruments (MBIs) have emerged as a popular approach to balance development and conservation objectives. However, their ability to accomplish this is often beset by poor implementation in practice. This is testament to a widening gap between the rate of policy development and implementation of MBIs and the maturity of research and evaluation on their design, and impact on affected stakeholders. Within this context, this paper examines multi-stakeholder perspectives to the adoption of Biodiversity Offsetting in England, an instrument designed to enable biodiversity losses in one place to be compensated through conservation improvements elsewhere. Analysis reveals issues associated with social and ecological compensation of biodiversity loss. Findings suggest that there is a need for a broader consideration of issues surrounding distributive justice, access to nature and the status of ownership over sites of common heritage when accounting for biodiversity loss and its compensation. This message is salient to both the study context as well as the burgeoning international practice of Biodiversity Offsetting. 相似文献
853.
Few studies have been conducted on the impact of carbon emissions disclosure on firms’ financial performance in emerging economies. Furthermore, comparison between accounting-based measures and market-based ones remains limited. This article examines the effect of carbon emissions reporting on the financial value of South African companies for the period 2010–2015. Using panel regression approaches, the findings show that, in most cases, carbon emission disclosure generates a positive relationship with ROA (an accounting-based indicator) but a negative association with MVA (a market-based indicator). The article concludes that accounting-based indicators offer more explanatory power for corporate greening initiatives. 相似文献
854.
Effects of Tourism and Topography on Vegetation Diversity in the Subalpine Meadows of the Dongling Mountains of Beijing,China 总被引:1,自引:0,他引:1
Subalpine meadows in the Dongling Mountains (located at E115o26′-115o40′, N40o00′-40o05′) of Beijing, China are important
for tourism and the provision of ecosystem services. However, because of poor management serious degradation has occurred
on these subalpine meadows. The aim of this paper is to present a quantitative analysis of effects of tourism disturbance
and topography on the status and diversity of montane meadow communities and to provide direction for improved management.
Sixty quadrats of 2 × 2 m2 along 10 transects were set up to collect data on site characteristics and vegetation status. The relationships between community
composition and structure, species diversity, and tourism disturbance and topographic variables were analyzed by multivariate
methods (TWINSPAN and CCA). The results showed that eight meadow communities were identified by TWINSPAN. Most of them were
seriously degraded. The first CCA axis identified an elevation and tourism disturbance intensity gradient, which illustrated
that tourism disturbance and elevation were most important factors influencing meadow types, composition and structure. Some
resistant species and response species to tourism disturbance were identified and can be used as indicator species of tourism
disturbance. Species richness, heterogeneity and evenness were closely related to tourism disturbance and elevation. It is
concluded that tourism disturbance must be controlled to enable grassland rehabilitation to occur in the meadows. Measures
of effective management of the meadows were discussed. 相似文献
855.
The history of the establishment and management philosophies of the mainland Portuguese Protected Areas was reconstructed
through the use of written records and oral history interviews. The objectives were to review the main philosophies in the
creation and management of these areas, to assess the influence of international PA models, to compare the Portuguese case
with other European and international literature concerning PAs and to discuss the value of the oral history in this research.
As main results, it was found that the initial management model of “Wilderness (or Yellowstone)” was replaced by the “new
paradigm” of PAs when the democracy was re-established. Changes in the management philosophies within this “new paradigm”
were also identified, which resulted in the transition of a “Landscape” to a “Nature conservation” model. After the establishment
of the Natura 2000 network, the “Biodiversity conservation” model prevailed. It was also found that the initiative for the
establishment of most PAs came from the government, although there were few cases of creation due to the action of NGOs and
municipalities. Finally, oral history interviews enabled the addition of information to the literature review, but also provided
more insight and detail to this history. 相似文献
856.
Quantifying the Effects of Conservation Practices on Soil,Water, and Nutrients in the Loess Mesa Ravine Region of the Loess Plateau,China 总被引:1,自引:0,他引:1
A large number of soil and water conservation programs have been implemented on the Loess Plateau of China since the 1950s.
To comprehensively assess the merits and demerits of the conservation practices is of great importance in further supervising
the conservation strategy for the Loess Plateau. This study calculates the impact factors of conservation practices on soil,
water, and nutrients during the period 1954–2004 in the Nanxiaohegou Catchment, a representative catchment in the Loess Mesa
Ravine Region of the Loess Plateau, China. Brief conclusions could be drawn as follows: (1) Soil erosion and nutrient loss
had been greatly mitigated through various conservation practices. About half of the total transported water and 94.8 % of
the total transported soil and nutrients, had been locally retained in the selected catchment. The soil retained from small
watersheds do not only form large-scale fertile farmland but also safeguard the Yellow River against overflow. (2) Check dam
was the most appropriate conservation practice on the Loess Plateau. In the selected catchment, more than 90 % of the retained
soil and water were accomplished by the dam farmland, although the dam farmland occupied only 2.3 % of the total area of all
conservation measures. Retention abilities of the characteristic conservation practices were in the following order: dam farmland > terrace
farmland > forest land and grassland. (3) The conservation practices were more powerful in retaining sediment than in reducing
runoff from the Loess Plateau, and the negative effects of the conservation practices on reducing water to the Yellow River
were relatively slight. 相似文献
857.
Management of forests, rangelands, and wetlands on public lands, including the restoration of degraded lands, has the potential
to increase carbon sequestration or reduce greenhouse gas (GHG) emissions beyond what is occurring today. In this paper we
discuss several policy options for increasing GHG mitigation on public lands. These range from an extension of current policy
by generating supplemental mitigation on public lands in an effort to meet national emissions reduction goals, to full participation
in an offsets market by allowing GHG mitigation on public lands to be sold as offsets either by the overseeing agency or by
private contractors. To help place these policy options in context, we briefly review the literature on GHG mitigation and
public lands to examine the potential for enhanced mitigation on federal and state public lands in the United States. This
potential will be tempered by consideration of the tradeoffs with other uses of public lands, the needs for climate change
adaptation, and the effects on other ecosystem services. 相似文献
858.
Dearing JA Bullock S Costanza R Dawson TP Edwards ME Poppy GM Smith GM 《Environmental management》2012,49(4):767-775
The ‘Perfect Storm’ metaphor describes a combination of events that causes a surprising or dramatic impact. It lends an evolutionary
perspective to how social-ecological interactions change. Thus, we argue that an improved understanding of how social-ecological
systems have evolved up to the present is necessary for the modelling, understanding and anticipation of current and future
social-ecological systems. Here we consider the implications of an evolutionary perspective for designing research approaches.
One desirable approach is the creation of multi-decadal records produced by integrating palaeoenvironmental, instrument and
documentary sources at multiple spatial scales. We also consider the potential for improved analytical and modelling approaches
by developing system dynamical, cellular and agent-based models, observing complex behaviour in social-ecological systems
against which to test systems dynamical theory, and drawing better lessons from history. Alongside these is the need to find
more appropriate ways to communicate complex systems, risk and uncertainty to the public and to policy-makers. 相似文献
859.
The present study was conducted to compare the 137Cs, 40K, 232Th, and 238U activity concentrations in epigeic moss (Hypnum cupressiforme) and lichen (Cladonia rangiformis). The activity levels in 37 moss and 38 lichen samples collected from the Marmara region of Turkey were measured using a gamma spectrometer equipped with a high purity germanium (HPGe) detector. The activity concentrations of 137Cs, 40K, 232Th, and 238U in the moss samples were found to be in the range of 0.36-8.13, 17.1-181.1, 1.51-6.17, and 0.87-6.70 Bq kg−1 respectively, while these values were below detection limit (BDL)-4.32, 16.6-240.0, 1.32-6.47, and BDL-3.57 Bq kg−1 respectively in lichen. The average moss/lichen activity ratios of 137Cs, 40K, 232Th, and 238U were found to be 1.32 ± 0.57, 2.79 ± 1.67, 2.11 ± 0.82, and 2.19 ± 1.02, respectively. Very low 137Cs concentrations were observed in moss and lichen samples compared to soil samples collected from the same locations in a previous study. Seasonal variations of the measured radionuclide activities were also examined in the three sampling stations. 相似文献
860.
Implications of differing input data sources and approaches upon forest carbon stock estimation 总被引:3,自引:0,他引:3
Michael A. Wulder Joanne C. White Graham Stinson Thomas Hilker Werner A. Kurz Nicholas C. Coops Ben?it St-Onge J. A. Trofymow 《Environmental monitoring and assessment》2010,166(1-4):543-561
Site index is an important forest inventory attribute that relates productivity and growth expectation of forests over time. In forest inventory programs, site index is used in conjunction with other forest inventory attributes (i.e., height, age) for the estimation of stand volume. In turn, stand volumes are used to estimate biomass (and biomass components) and enable conversion to carbon. In this research, we explore the implications and consequences of different estimates of site index on carbon stock characterization for a 2,500-ha Douglas-fir-dominated landscape located on Eastern Vancouver Island, British Columbia, Canada. We compared site index estimates from an existing forest inventory to estimates generated from a combination of forest inventory and light detection and ranging (LIDAR)-derived attributes and then examined the resultant differences in biomass estimates generated from a carbon budget model (Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3)). Significant differences were found between the original and LIDAR-derived site indices for all species types and for the resulting 5-m site classes (p?<?0.001). The LIDAR-derived site class was greater than the original site class for 42% of stands; however, 77% of stands were within ±1 site class of the original class. Differences in biomass estimates between the model scenarios were significant for both total stand biomass and biomass per hectare (p?<?0.001); differences for Douglas-fir-dominated stands (representing 85% of all stands) were not significant (p?=?0.288). Overall, the relationship between the two biomass estimates was strong (R 2?=?0.92, p?<?0.001), suggesting that in certain circumstances, LIDAR may have a role to play in site index estimation and biomass mapping. 相似文献