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921.
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
922.
The present article analyses a unique database of 220 dam-related environmental conflicts, retrieved from the Global Atlas on Environmental Justice (EJAtlas), and based on knowledge co-production between academics and activists. Despite well-known controversial, social, and environmental impacts of dams, efforts to increase renewable energy generation have reinstated the interest into hydropower development globally. People affected by dams have largely denounced such ‘unsustainabilities’ through collective non-violent actions. Nevertheless, we found that repression, criminalization, violent targeting of activists and assassinations are recurrent features of conflictive dams. Violent repression is particularly high when indigenous people are involved. Indirect forms of violence are also analysed through socio-economic, environmental, and health impacts. We argue that increasing repression of the opposition against unwanted energy infrastructures does not only serve to curb specific protest actions, but also aims to delegitimize and undermine differing understanding of sustainability, epistemologies, and world views. This analysis cautions that allegedly sustainable renewables such as hydropower often replicates patterns of violence within a frame of an ‘extractivism of renewables’. We finally suggest that co-production of knowledge between scientists, activists, and communities should be largely encouraged to investigate sensitive and contentious topics in sustainability studies. 相似文献
923.
Brito Pedro Elias Marcos Silva-Neto Carlos Sujii Edison Silva Daniela Gonçalves Bruno Franceschinelli Edivani 《Environmental science and pollution research international》2020,27(31):38654-38661
Environmental Science and Pollution Research - The presence of Brazilian native bees can improve tomato production by increasing pollination effectiveness. However, the extensive use of pesticides... 相似文献
924.
Biochar derived from pyrolysis has received much attention recently as a soil additive to sequester carbon and increase soil fertility. Hydrochar, a brown, coal-like substance produced via hydrothermal carbonization, has also been suggested as a beneficial soil additive. However, before soil application, both types of char need to be tested for potential toxic effects. The aim of this study was to develop simple, inexpensive, and easy-to-apply test procedures to identify negative effects of chars but not to provide false-negative results. The following tests, based partly on ISO norm biotoxicity test procedures, were chosen: (i) cress germination test for gaseous phytotoxic emissions; (ii) barley germination and growth test; (iii) salad germination test; and (iv) earthworm avoidance test for toxic substances. Test reproducibility was ensured by carrying out each test procedure three times with the same biochar. Several modifications were necessary to adapt the tests for biochars/hydrochars. The tested biochar did not induce negative effects in any of the tests. In contrast, the beet-root chip hydrochar showed negative effects in all tests. In an extension to the regular procedure, a regrowth of the harvested barley shoots without further nutrient additions yielded positive results for the hydrochar, which initially had negative effects. This implies that the harmful substance(s) must have been degraded or they were water soluble and leached. Tests with a biochar and hydrochar showed that the proposed modified quick-check test procedures provide a fast assessment of risks and effects of char application to soils within a short period of time (<2 wk). 相似文献
925.
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
926.
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
927.
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
928.
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
929.
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
930.
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