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Investigating tourism and climate change: the case of St Francis Bay and Cape St FrancisGrant, Bronwyn Caroline January 2015 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, August 2015. / Climate change literature is growing rapidly, with increasing literature being
produced on the relationship between climate change and tourism. Globally, tourism
is very dependent on the climate and the impacts of climate change may alter
tourism flow and demand. Developing countries are likely to be the most affected by
climate change and its effects on tourism which is worrying as this sector is a huge
contributor to their economy. South African tourism relies heavily on its environment
to attract tourists and give a satisfactory travel experience; climate change is a threat
to the environment and thus a major concern for South Africa. This thesis
investigates the perceptions of climate change threats within the tourism sector by
exploring how perceptions may influence behaviour and how the tourism sector will
respond to a changing climate. Research was carried out in two coastal towns, St
Francis Bay and Cape St Francis in the Eastern Cape Province. These towns are
dependent on their tourism sectors to drive their economies. These towns are
dependent on their local tourism sector to drive their economy. The results indicate
that while both the tourists and tourist accommodation establishments are aware of
the threat of climate change and are concerned about its impacts, there is very little
adaptation being implemented. While the level of concern varies among the
accommodation establishments, there appears to be no perceived significant
relationship between the threat of sea level rise and their distance from the coastline.
Tourism Climate Index calculations for the two towns suggest that the climate is
worsening in terms of tourist comfort, and project that the towns will become less
attractive for tourism based on their climate. A Digital Elevation Model developed for
the towns however shows that the projected sea level rise for 2050 and 2100 will
result in parts of the beaches and a protective artificial spit being washed away. The
lack of climate change planning to deal with these impacts is directly linked to their
perception. The tourist accommodation establishments do not believe they need to
take major action and rather feel the government should respond to climate change.
Overall, the results indicate that there is a need for further research into bottom-up
approaches to climate change, to better plan and implement successful climate
change mitigation and adaptation which can be done through educating individuals
and businesses within the tourism sector.
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Climate change risk communication and asset adaptation of indigenous farmers in the Delta State of NigeriaEbhuoma, Eromose Ehije January 2017 (has links)
A thesis submitted to the Faculty of Science, School of Geography and Environmental Studies, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, October, 2017. / The purpose of this study was to examine how subsistence farmers in the Delta State of Nigeria employed their asset portfolios i.e. human, financial, social, natural and physical capitals to build their adaptive capacity and resilience to climate variability and change. The study was also interested in understanding the extent to which climate change risk communication facilitated the protection and adaptation of subsistence farmer’s assets in the face of extreme weather warnings.
Primary data were obtained using the Participatory Climate Change Adaptation Appraisal (PCCAA), which comprises both the asset vulnerability analytical and the asset-based adaptation operational frameworks. The systems thinking approach, together with the asset vulnerability analytical framework were also used as an operational vulnerability framework to highlight the myriad factors undermining the rural poor from maximising their asset portfolios during food production. Focus group discussions and semi-structured interviews facilitated the use of the PCCAA tools.
Meteorological data reinforced subsistence farmer’s perception (62%) that there has been an increase in temperature within the last decade, which have adversely affected on groundnut production. The farmers (92%) also listed heavy rainfall event and flooding as a climatic variable that impede their ability to produce cassava throughout the year. This is because their farmlands, which are generally low-lying, are always inundated for approximately four months every year. Nonetheless, the farmers still engaged in cassava production annually by adopting a strategy indigenously referred to as elelame (follow-water-go).
It is important to mention that in spite of the rapidly changing climate, the subsistence farmers did not rely on Seasonal Climate Forecast (SCF) in order to determine the appropriate time to grow their food. Instead, they relied on their Indigenous Knowledge
Systems (IKS) not limited to cloud observations, croaking of frogs and peculiar sounds made by the swamp chickens. However, the farmers acknowledged that their IKS have not been as reliable as it has always been in the past decades. Nonetheless, the farmers underlined being misled by an inaccurate scientific forecast in 2013 and, a lack of trust in the source of the forecast are some of the reasons they continue to rely primarily on IKS.
With climate change expected to continue occurring at unprecedented levels in Nigeria, it is crucial to build subsistence farmers trust in SCF while simultaneously not undermining the value of their IKS. This is because there is growing consensus that if subsistence farmers continue to rely on IKS alone, the key assets that play a huge role in food production will likely be eroded. This will adversely hamper households’ ability to continue obtaining the livelihood they aggressively pursue. Thus, a useful starting point will be to generate a “unified” forecast whereby SCF compensates for the limitations of farmer’s IKS. However, for the unified forecast to make meaningful contributions to the ways in which farmers produce their food and protect their assets in anticipation of an extreme weather forecast, it must be communicated through the various mediums that the farmers rely upon to receive vital pieces of information.
Keywords: Indigenous knowledge systems, seasonal climate forecast, climate change risk communication, Delta State, Nigeria. / LG2018
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Modelling isoprene emissions over Southern Africa based on climate change scenariosWeston, Michael John 27 February 2012 (has links)
M.Sc., Faculty of Science, University of the Witwatersrand, 2011 / Biogenic volatile organic compounds (BVOCs), in the presence of nitrogen oxide gases
(NOx), play a role in the production of tropospheric ozone (O3) which is an effective
greenhouse gas and is hazardous to human health (Haagen-Smit, 1952, Chameides et al,
1988, Atkinson, 2000, Kanakidou et al, 2004). Isoprene is a single BVOC that accounts
for over 50% of all emitted BVOCs. Isoprene emissions are species specific and vary
according to temperature, light and leaf area index. Climate change studies predict that
the geographic distribution of species, temperature ranges, light intensity and leaf area
index will shift, thus altering future isoprene emissions.
Several attempts to model BVOC emissions have been undertaken in an effort to quantify
BVOC emission rates and the impact on ozone formation. The most widely used and
empirically tested emission algorithms to date were developed by Guenther et al (1993)
and are incorporated into the emission model Model of Emissions of Gases and Aerosols
from Nature (MEGAN). MEGAN is used in this study to model isoprene emission rates
over southern Africa under current and future climate conditions. Current and future
climate conditions are taken from the regional climate model, Conformal-Cubic
Atmospheric Model (C-CAM), which has been shown to simulate current climate well
for the region. Emissions were modelled for January and July only, to represent summer
and winter conditions.
January isoprene emission rates for the current climate range from 0 to 1.41 gm-2month-1
and total 0.938 Tg of isoprene for the study domain. The highest emission rates are
caused by combinations of driving variables which are: high temperature only; high
temperature and high leaf area index; high emission factor and high leaf area index.
Emission rates effectively shut down in July due to low temperatures and low leaf area
index. July emission rates range from 0 to 0.61 gm-2month-1 and total 0.208 Tg of
isoprene. Temperature is shown to cause the greatest variation in isoprene emission rates,
and thus future scenarios represent an increase in temperature only. The spatial
distribution of future emission rates does not shift when compared to current emission
rates, but does show an increase in magnitude. Future emission totals for January increase
iv
by 34% to 1.259 Tg of isoprene and the July emission total increases by 38% to 0.289 Tg
of isoprene.
Future emission rates responded to temperature as expected, increasing in magnitude, rate
of change and range of temperature over which the greatest rate of change occurs. Three
areas demonstrating the highest increase in emission rates and highest future emission
rates were identified. As temperature was the only variable altered in future scenarios,
these areas can be deemed as areas most sensitive to changes in temperature. These areas
are situated near the Angola-Namibia border, the Northern Interior of South Africa and
the low-lying areas of Mozambique.
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Carbon encounters: cognizing the calculus of climate changeBattle, Angela January 2016 (has links)
Thesis (M.A. (Anthropology))--University of the Witwatersrand, Faculty of Humanities, School of Social Sciences, 2016. / Governments, like South Africa, are implementing carbon tax and carbon credit programs to incent businesses to lower their GHG emissions. That is not to say there are not loftier motivations in the wider world, but in this study we have mostly encountered Homo Economicus. Our observations have noted that people either want to make money or save money by way of participating in the green economy. Earth’s threatening posture is yet to change our “habitus”. The changes so far are from economic coercion and not ecological conviction. And it’s primarily prompted through the scientific community, who are understandably, the first responders to a threat with slow and mostly imperceptible reverberations. The responses of those trying to make money, involve participating in the process of carbon commodification. CERs are a new form of currency available to those able to deploy labor and capital in efforts to capture carbon molecules and prevent their creation. The looming South African carbon tax has spurred organizations to lower their emissions so as not to effect bottom-line profitability. [Taken from the conclusion. No abstract provided] / MT2017
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Evaluation of future design rainfall extremes and characteristics using multiple-model and multiple-scenario climate change modelsUnknown Date (has links)
Climate models are common tools for developing design standards in the hydrologic field; however,
these models contain uncertainties in multi-model and scenario selections. Along with these uncertainties,
biases can be attached to the models. Such biases and uncertainties can present difficulties in predicting
future extremes. These hydrologic extremes are believed to be non-stationary in character. Only in the
recent past have model users come to terms that the current hydrologic designs are no longer relevant due
to their assumption of stationarity. This study describes a systematic method of selecting a best fit model in
relationship to location and time, along with the use of that best fit model for evaluation of future extremes.
Rain gage stations throughout Florida are used to collect daily precipitation data used in extreme precipitation and quantitative indices. Through these indices conclusions are made on model selection and
future extremes, as they relate to hydrologic designs. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.
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Estudo espaço-temporal da variação dos parâmetros físicos e químicos no transecto 30ºS do Oceano Atlântico Sul / Spatial and temporal study of ohysical and chemical parameters on transect 30ºS of South Atlantic OceanDelfim, Ricardo 11 October 2012 (has links)
Na década de 90 surge a primeira tentativa de gerar dados capazes de legitimar um modelo climático mundial detalhado: O Experimento de Circulação Oceânica Global (World Ocean Circulation Experiment - WOCE) Dentro dos diversos subprogramas inseridos no WOCE destaca-se o programa Hidrográfico (WHP). A JAMSTEC (Japan Marine Science and Tecnology Center), após cerca de uma década volta a reocupar algumas estações do WHP-WOCE, com o programa BEAGLE (Blue Earth Global Expedition), tendo como proposta detectar e quantificar alterações correspondentes ao aquecimento global. A I Comissão Oceanográfica Trans-Atlântica (TAI 2009) também constituiu um projeto de reocupação da seção A10, linha central do Oceano Atlântico Sul (~30?S), previamente amostrada pelo WHP-WOCE e BEAGLE, tendo como objetivo identificar alterações espaciais e temporais dos parâmetros oceanográficos nas últimas duas décadas. Considerando os valores de temperatura e salinidade foi evidenciada a presença de pelo menos, cinco massas d\'água: i) Água Tropical de Superfície (ATS) acima da isopícnal ?0= 26,70 ii) Água Central do Atlântico Sul (ACAS) abaixo da isopícnal ?1= 27,05 iii) Água Intermediária Antártica (AIA) abaixo da isopícnal ?2= 27,20 (iv) Água Profunda do Atlântico Norte (APAN) abaixo da isopícnal ?3= 27,70 v) Água Antártica de Fundo (AAF). Nas camadas superficiais dos três programas, notou-se uma proporcionalidade inversa entre as concentrações de nutrientes e oxigênio dissolvido. O Programa TAI ao longo de todo o transecto A10, apresentou as menores concentrações de nutrientes abaixo dos 1000 dbar. O WHP-WOCE foi mais aquecido que os outros programas nas camadas superficiais. Nas profundidades acima da termoclina (~1000 dbar), na bacia leste o Programa BEAGLE apresentou diferenciações que sugerem uma atividade mais intensa de ressurgência, para seu ano de amostragem do que nos anos dos Programas WHP-WOCE e TAI. Porém baseado nos resultados do Programa TAI, na extremidade leste da Bacia do Atlântico Sul, pode-se inferir que há afloramento da Água Central do Atlântico Sul (ACAS), provinda de aproximadamente 900 dbar de profundidade, sobre a Plataforma Continental Sul Africana. / In the 90s comes the first attempt of generate data able to legitimize a comprehensive global climate model: The Wolrd Ocean Circulation Experiment (WOCE). Within various subprograms inserted into the WOCE, highlight the WOCE Hydrographic Program (WHP). The JAMSTEC (Japan Marine Science and Technology Center), after about a decade back to reoccupy some stations of WOCE-WHP, with a program called BEAGLE (Blue Earth Global Expedition), proposing to detect and quantify changes related to global warming. The 1st Trans-Atlantic Oceanographic Commission (TAI 2009) was also created as a project of A10 section reoccupation, aiming to identify spatial and temporal changes in oceanographic parameters after two decades WOCE-WHP and BEAGLE sampling. The A10 section, represents the axis of South Atlantic Ocean (~ 30?S). Considering the values of temperature and salinity the presence of at least five water masses can be inferred: i) Surface Tropical Water (ATS) above isopícnal ?0 = 26.70, ii) South Atlantic Central Water (ACAS) below the isopícnal ?1 = 27.05 iii) Antarctic Intermediate Water (AIA) below the isopícnal ?2 = 27.20, (iv) North Atlantic Deep Water (APAN) below the isopícnal ?3 = 27.70, v) Antarctic Bottom Water (AAF). On the superficial layers of the three programs, it was noted an inverse proportionality between the concentrations of nutrients and dissolved oxygen. The TAI program, throughout the A10 transect, showed the lowest concentrations of nutrients below 1000 dbar. The warmer in the superficial layers was WOCE-WHP. On the layers above the thermocline (~ 1000 dbar), the BEAGLE Program around East Basin, showed some anomalies that suggest its sampling happened during some more intense upwelling activity, for its year than in years of WHP- WOCE and TAI programs. But based on the results of the TAI Program, at the east end of the South Atlantic Basin, it\'s possible to infer that there is upwelling of South Atlantic Central Water (ACAS), coming from about 900 dbar depth on the South African continental shelf.
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A composição isotópica do CO2 respirado e sua variabilidade sazonal na Amazônia Oriental / Isotopic composition of respired CO2 and seasonal variability in the Amazon tropical ForestIshida, Françoise Yoko 24 September 2007 (has links)
O presente estudo foi conduzido na Floresta Nacional do Tapajós (FLONA) (2°51'S 54°58'W) localizado no km 67 nos anos de 2003 e 2004. O objetivo foi avaliar as mudanças na composição isotópica do carbono respirado por uma floresta e seus componentes (δ13CR), além da composição isotópica do material orgânico (δ13C) de folhas, solo, serapilheira e madeira morta. A técnica da reta de Keeling e a equação de Farquhar foram utilizadas para determinar o valor de δ13CR e para estimar o valor de ci/ca, respectivamente. De acordo com os resultados, o δ13C respirado pelo ecossistema foi significativamente influenciado pela sazonalidade em 2003. O δ13C das folhas apresentou uma estratificação significativa ao longo do perfil vertical, apresentando valores mais enriquecidos no topo de dossel. O valor médio de ci/ca apresentou um aumento vertical no sentido do sub-bosque. As correlações encontradas entre os valores de δ13C respirado com temperatura, DPV, RFA e precipitação indicam uma estreita relação entre as trocas gasosas e variabilidade climática local, onde a intensificação nas amostragens ao longo de dois anos consecutivos confirmou as diferenças sazonais observadas anteriormente. A definição dos padrões isotópicos de um ecossistema em diferentes condições climáticas é de fundamental importância para a melhor compreensão do ciclo do carbono, desde uma folha até o ecossistema; especialmente na região Amazônica onde as atividades antrópicas têm aumentado significativamente, fortalecendo o cenário de mudanças no clima. / This study was conducted in 2003 and 2004 at the km 67 old growth forest in the Tapajós National Forest (2 ° 51'S 54 ° 58'W). The objective was measure the carbon isotope ratio (13C/12C) of respired CO2 from the entire ecosystem and isotope composition of organic components leaves, soil, litter and dead wood. The Keeling plot technique and Farquhar's leaf model was used to examine the physiological drivers of the isotopic composition of these components as well as the seasonal response for them. A variation of respired δ13CR - CO2 by the ecosystem was well related with precipitation variation, VPD and PAR, and a significant seasonal difference was found in 2003. The δ13C of leaf organic matter showed a clear stratification along the vertical profile. The estimated ci/ca ratio values showed significant differences between heights and seasons. The results indicated that the isotopic composition of respired CO2 and organic matter was sensitive to microclimatic variations; so far the δ13C values can be used to understand how environmental changes can affect the carbon cycle at ecosystem scale.
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Projeções futuras do oceano Atlântico Sudoeste em dois cenários de aquecimento global / Future projections of the Southwest Atlantic in two global warming scenariosPereira, Augusto Andrade 19 December 2011 (has links)
O Atlântico Sudoeste comporta uma das regiões oceânicas mais energéticas do planeta: a Confluência Brasil-Malvinas (CBM). Essa região encerra o giro subtropical do Atlântico Sul e possui fundamental importância para a dinâmica desse oceano bem como para o clima regional. Através de saídas de modelos numéricos acoplados do 4°?elatório do IPCC, descreve-se o comportamento dessa região em dois cenários futuros de aquecimento global: um de elevada emissão de gases estufa (A1b) e o outro mais ameno em termos de impactos antrópicos (B2). Ambos os cenários apresentaram fortes tendências de aumento de temperatura sobretudo na superfície (chegando a 0,065°C/ano no cenário A1b e 0,055°C/ano no B2). A salinidade de superfície mostrou forte tendência positiva do Equador até a região da CBM, e negativa em maiores latitudes. A posição média da CBM desloca-se em aproximadamente 1,1° para sul no cenário A1b (entre 2066 e 2100) e 0,9° no cenário B2. O padrão espectral dessa posição (dominado pelo ciclo anual no século XX) é dominado pela variabilidade de baixa frequência no cenário A1b. Tais modificações na média e no espectro da posição da CBM estão associados à intensificação e mudança da Corrente do Brasil. / Southwestern Atlantic comprises one of the most energetic region of the world: Brazil-Malvinas Confluence (BMC). This region lies within the Southern Atlantic Subtropical Gyre and holds fundamental importance for this oceanic dynamics as well as for the regional climate. Through numerical modeling output coupled to IPCC\'s 4th Report, it is sunk to describe this region behavior for two distinct future scenarios: high greenhouse gases emission (A1b) and a milder one in terms of anthropic impacts (B2). Both scenarios have shown strong temperature increasing tendencies, especially on the surface (reaching up to 0.065°C/year in A1b and 0.055°C/year in B2). Surface salinity have also shown strong positive tendency from the Equator to the BMC region, and negative in higher latitudes. BMC medium position is shifted around 1.1°S in A1b scenario (between 2066 and 2010) and 0.9° in B2. Spectral pattern on this position (dominated for XX century annual cycle) is controlled by low-frequency variabilities in A1b scenario. These modifications in average and spectral patterns of BMC position are linked to the intensification and changing of Brazil current.
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Analise da expressão gênica da Na+/K+-ATPase e dos parâmetros fisiológicos no siri Callinectes danae submetido a cenários futuros de acidificação oceânica em laboratório /Mota, Andressa Cristina Ramaglia January 2018 (has links)
Orientador: Leandro de Castro Mantovani / Resumo: Acidificação oceânica, processo resultante das emissões de gás carbônico (CO2) na atmosfera pelas atividades de natureza antrópica, vem causando nas últimas décadas uma modificação no equilíbrio químico do sistema bicarbonato/carbonato e consequentemente uma diminuição do pH dos oceanos. Estimativas apontam que esta diminuição pode ser de 0,7 unidades até ano de 2300, o que pode afetar o crescimento, reprodução e até mesmo a sobrevivência das espécies. Nesse sentido, são necessários estudos que avaliem o impacto da acidificação oceânica ao nível fisiológico e molecular nas diferentes espécies marinhas. O siri Callinectes danae é um importante recurso ecológico e econômico da Região da Baixada Santista e habitante de diferentes faixas de salinidade. O presente estudo avaliou os efeitos da acidificação oceânica no siri C. danae sobre um conjunto de parâmetros fisiológicos (consumo de oxigênio, excreção de amônia, razão O:N, índice hepatossomático e capacidade osmo-e ionorregulatória da hemolinfa), e a expressão gênica da Na+/K+- ATPase, enzima importante no processo de osmorregulação e equilíbrio ácido base. Os animais foram mantidos em diferentes salinidades (20, 25, 30, 35 e 40) e nos pHs 8,0 (controle) e 7,3 (acidificado) por um período de três e trinta dias. Foi observado aumento no consumo de oxigênio nas salinidades 25 (3 dias), 20 e 40 (30 dias) provavelmente devido a uma maior necessidade energética para a manutenção de sistemas relacionado a regulação ácido-base. També... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Oceanic acidification, a process resulting from the emission of carbon dioxide (CO2) in the atmosphere by activities of anthropic nature, has been causing in recent decades a change in the chemical balance of the bicarbonate / carbonate system and consequently a decrease in the pH of the oceans. Estimates indicate that this decrease can be 0.7 units per year of 2300, which can affect the growth, reproduction and even survival of the species. In this sense, studies are needed to evaluate the impact of oceanic acidification on physiological and molecular levels in different marine species. The Callinectes danae crab is an important ecological and economic resource of the Region of the Baixada Santista and inhabitant of different ranges of salinity. The present study evaluated the effects of ocean acidification on C. danae crab on a set of physiological parameters (oxygen consumption, ammonia excretion, O: N ratio, hepatosomatic index and osmo-and ionoregulatory capacity of hemolymph), and gene expression of Na + / K + - ATPase, an important enzyme in the process of osmoregulation and acid base balance. The animals were kept at different salinities (20, 25, 30, 35 and 40) and at pHs 8.0 (control) and 7.3 (acidified) for a period of three and thirty days. It was observed an increase in the oxygen consumption in salinities 25 (3 days), 20 and 40 (30 days) probably due to a greater energy requirement for the maintenance of systems related to acid-base regulation. Metabolic depressi... (Complete abstract click electronic access below) / Mestre
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The barriers and opportunities of resource efficiency and cleaner production within a South African contextPage, Andre Paul January 2017 (has links)
Thesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2017. / This research study investigates how environmental tools such as Resource Efficiency and Cleaner Production (RECP) can contribute to sustaining and supporting economic growth in South Africa. Resource optimisation is crucial when considering the concept of sustainable development. It also contributes to addressing the challenges of global warming and climate change, which in turn threaten industrial growth and sustainability in the long term. The study places emphasis on the barriers that prevent industry from implementing RECP recommendations, and identifies opportunities that could potentially reposition businesses should they consider implementation. It also promotes other sustainability tools that are available through collaboration with international entities, and this could be of great benefit to the South African industry. Factors of unemployment and urbanisation restricts national growth to some degree, hence the study explores how RECP can contribute to job retention by introducing new resource optimisation methodologies for the manufacturing sector, Moreover, it examines the imbalance between the demand as well as limitations of these resources. Through the compilation of data collated from questionnaires completed by industry, government and civil society participants, this study looks at achieving a balance between environmental sustainability and growth. It also looks at aligning this balance with the integration of specific economic and environmental policies, which also includes social aspects. What comes through significantly in this research is the lack of awareness within industry in terms of RECP, as well as the importance of prioritising the uptake of environmental initiatives to ensure that industry is compliant with the stringent policies and legislation designed by government to drive the sustainability process. Consequently the study shows that communication between public and private sector, as well as the awareness raising and marketing of sustainability to consumers need to be improved. An analysis of the various government support mechanisms is conducted, in respect of how industry could potentially leverage growth and drive positive change within their businesses. In addition to RECP, emphasis is placed on other Sustainable Consumption and Production (SCP) initiatives and tools that could possibly entrench sustainable practices and help with their incorporation into their business strategies.
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