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Topic Review
Nickel Toxicity Effects on Crop and Soil
Low or moderate nickel concentrations in soils can cause environmental problems. The main effects of this potentially toxic element on the soil biota and the most common crop species are addressed.
  • 1.2K
  • 11 Nov 2022
Topic Review
Essential Oils and Their Application
EOs are secondary metabolites synthesized by plants. As many other secondary metabolites, they possess different bioactivities that have been employed for centuries by utilizing the whole plant or by the application of the EOs previously extracted.
  • 1.2K
  • 08 Feb 2021
Topic Review
Clean Development Mechanism
The Clean Development Mechanism (CDM) is one of the Flexible Mechanisms defined in the Kyoto Protocol (IPCC, 2007) that provides for emissions reduction projects which generate Certified Emission Reduction units (CERs) which may be traded in emissions trading schemes. The market crashed in 2012 when the value of credits collapsed and thousands of projects were left with unclaimed credits. The struggle about what to do with the old credits sank the 2019 COP 25 in Madrid. The CDM, defined in Article 12 of the Protocol, was intended to meet two objectives: "Annex I" parties are the countries listed in Annex I of the treaty, the industrialized countries. Non-Annex I parties are developing countries. The CDM addresses the second objective by allowing the Annex I countries to meet part of their emission reduction commitments under the Kyoto Protocol by buying Certified Emission Reduction units from CDM emission reduction projects in developing countries. Both the projects and the issue of CERs units are subject to approval to ensure that these emission reductions are real and "additional." The CDM is supervised by the CDM Executive Board (CDM EB) under the guidance of the Conference of the Parties (COP/MOP) of the United Nations Framework Convention on Climate Change (UNFCCC). The CDM allows industrialized countries to buy CERs and to invest in emission reductions where it is cheapest globally. Between 2001, which was the first year CDM projects could be registered and 7 September 2012, the CDM issued 1 billion Certified Emission Reduction units. As of 1 June 2013, 57% of all CERs had been issued for projects based on destroying either HFC-23 (38%) or N2O (19%). Carbon capture and storage (CCS) was included in the CDM carbon offsetting scheme in December 2011. However, a number of weaknesses of the CDM have been identified. Several of these issues were addressed by the new Program of Activities (PoA), which moves to approving 'bundles' of projects instead of accrediting each project individually. In 2012, the report Climate Change, Carbon Markets and the CDM: A Call to Action said governments urgently needed to address the future of the CDM. It suggested the CDM was in danger of collapse because of the low price of carbon and the failure of governments to guarantee its existence into the future. Writing on the website of the Climate & Development Knowledge Network, Yolanda Kakabadse, a member of the investigating panel for the report and founder of Fundación Futuro Latinamericano, said a strong CDM is needed to support the political consensus essential for future climate progress. "Therefore we must do everything in our hands to keep it working," she said.
  • 1.2K
  • 17 Oct 2022
Topic Review
Bio-energy with Carbon Capture and Storage
Bio-energy with carbon capture and storage (BECCS) is a potential greenhouse gas mitigation technology which produces negative carbon dioxide emissions by combining bioenergy (energy from biomass) use with geologic carbon capture and storage. The concept of BECCS is drawn from the integration of trees and crops, which extract carbon dioxide (CO2) from the atmosphere as they grow, the use of this biomass in processing industries or power plants, and the application of carbon capture and storage via CO2 injection into geological formations. There are other non-BECCS forms of carbon dioxide removal and storage that include technologies such as biochar, carbon dioxide air capture and biomass burial and enhanced weathering. According to a recent Biorecro report, there is 550 000 tonnes CO2/year in total BECCS capacity currently operating, divided between three different facilities (as of January 2012). In the IPCC Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC), BECCS was indicated as a key technology for reaching low carbon dioxide atmospheric concentration targets. The negative emissions that can be produced by BECCS has been estimated by the Royal Society to be equivalent to a 50 to 150 ppm decrease in global atmospheric carbon dioxide concentrations and according to the International Energy Agency, the BLUE map climate change mitigation scenario calls for more than 2 gigatonnes of negative CO2 emissions per year with BECCS in 2050. According to Stanford University, 10 gigatonnes is achievable by this date. The Imperial College London, the UK Met Office Hadley Centre for Climate Prediction and Research, the Tyndall Centre for Climate Change Research, the Walker Institute for Climate System Research, and the Grantham Institute for Climate Change issued a joint report on carbon dioxide removal technologies as part of the AVOID: Avoiding dangerous climate change research program, stating that "Overall, of the technologies studied in this report, BECCS has the greatest maturity and there are no major practical barriers to its introduction into today’s energy system. The presence of a primary product will support early deployment." According to the OECD, "Achieving lower concentration targets (450 ppm) depends significantly on the use of BECCS".
  • 1.2K
  • 25 Oct 2022
Topic Review
Toxic Metals Contamination
Concentrations of potentially toxic metals including Cd, Cu, Pb, Cr, U, Th in surface water and sediment samples collected from a river were analyzed to assess the contaminations, distribution characteristics and sources of these metals. The contents of the metals were lower than the standard levels set by WHO for drinking water. However, U and Th contents were far beyond the background values of surface water. The concentrations of Cd, Cr and U in sediments were higher than the background values and the Probable Effect Level (PEL) of sediment quality guidelines (SQGs) which may result in high potential harmful biological effects to aquatic ecosystem. Based on the contamination factor (CF), geo-accumulation index (Igeo) and potential ecological risk index (RI), Cd, Cr and U were considered to be the metals that mainly contribute to the contamination of sediments. The calculation results also indicated that the sites adjacent to the uranium ore field were highly polluted. Results of cluster analysis, principal component analysis and correlation analysis revealed that Cr, Pb, U, Th were highly correlated with each other. These metals were mainly originated from both anthropogenic source and natural processes, especially emissions from uranium mining and quarrying, whereas Cd mostly came from anthropogenic source (agricultural activities) of the upper reaches of the river.
  • 1.2K
  • 30 Oct 2020
Topic Review
Weeds in Agricultural Fields
Weeds are significant contributors to the decline in crop yield and quality. Weeds compete with crops in terms of nutrients, water, and sunlight.
  • 1.1K
  • 18 Jan 2022
Topic Review
Eco-safe Rural Roads assessment
Rural roads are important for the communities in the hilly areas of Nepal as they introduce livelihood opportunities at the local level, provide better access to the health care, education and resources. Yet, most of the rural roads in Nepal are unplanned and non-engineered, and these roads are often closed for many months during and after the monsoon. Such roads require huge investments, especially post-monsoon, to clear debris and to keep them operational. In parallel, there is evidence that such roads lead to large number of slope failures and accelerated sedimentation, which degrade the environment and ecosystem services. To remedy such roadside slope failures, eco-engineering practices were tested and demonstrated in partnership with three communities in the Panchase Region of the Nepal’s Central-Western Middle Hills.  Eco-engineering is a hybrid approach, combining civil engineering works for drainage and slope stability, with the plantation of deep-rooted vegetation. It is one activity contributing to Nature based Solutions (NbS) for the sustainable and long-term operation of the rural roads in the Panchase geographic region. This paper describes the inter-disciplinary and community-based research, monitoring and evaluation methods applied, including, the establishment of onsite demonstration plots and Rhizotrons in which Key performance Indicators (KPI) analysis of plant species were performed. The results demonstrated the effectiveness of eco-engineering for reducing risk, while creating ecological co-benefits along rural roads (or eco-safe roads) in hilly areas.  Based on this research, an ‘Eco-safe Rural Road Assessment Framework’ was developed, outlining the systematic process to be followed for the design of eco-safe rural roads for more sustainable road construction and maintenance. The ecological engineering practices which are being promoted by this framework have been accepted by communities and could be further implemented by local government bodies and up-scaled in other similar hilly areas around the country. 
  • 1.1K
  • 30 Oct 2020
Topic Review
Groundwater dynamics
Analytical solutions of groundwater dynamics in an elongated aquifer subjected to general time-dependent recharge are presented. The lateral boundaries are specified heads with the head variations governed by general time-dependent functions.  General recharge function was not considered in previous works of this kind. Both single and double-porosity aquifers are considered. The solution is obtained using Fourier sine and Laplace transformations, followed by an inverse Fourier-Laplace transform involving residue theorem and convolutional integral. For the unconfined single-porosity aquifer case, the exact time-domain solution is obtained using the residue theorem; for the unconfined double-porosity aquifer case, the time-domain head is calculated using the de Hoog inverse Laplace algorithm. The presented solution can be used to estimate the hydraulic parameters of 1) groundwater head variation of a river basin aquifer subjected to general lateral head variation and recharge; 2) groundwater head variation in a double-porosity elongated fractured anticline; 3) groundwater depletion of an elongated fractured anticline subjected to recharge due to rainfall or snowmelt to its adjacent alluvial aquifer.  In addition, the presented solution can be utilized to optimize the irrigation pattern in a cropland between two trench drains to control the groundwater mound.
  • 1.1K
  • 23 Dec 2020
Topic Review
Climate-Smart Agriculture of Hungarian Agribusiness
Climate change and agriculture interact with each other in many ways and have a complex impact. The agriculture sector needs to be prepared to adapt to the expected effects of climate change, and emphasis must be placed on prevention to achieve emission reduction targets. The research explores the current situation in the agricultural sector, the risks of climate change, as well as the Climate-Smart Agriculture (CSA) solutions that appear at Hungarian agribusiness. Examining the climate innovation activities of farms shows a coherence of the practical application. The research is based on a questionnaire survey of Hungarian agribusiness and the country directorates of the National Chamber of Agriculture. The investigation confirmed that although farmers are susceptible to Agri-Innovation, they only partly exploit the potential of digitalization. For agriculture, the spread of agricultural digitalization and technology transfer is an excellent opportunity to increase agricultural production, maintain and improve its market position, and increase its digital maturity, which can also enhance the integration of climate innovation and sustainability aspects supporting the green economic development.
  • 1.1K
  • 24 Sep 2021
Topic Review
Microalgae-Based Biorefineries: Challenges and Future Trends
Microalgae-based biorefineries allow the simultaneous production of microalgae biomass enriched in a particular macromolecule and high-added and low-value products if a proper selection of the microalgae species and the cultivation conditions are adequate for the purpose. 
  • 1.1K
  • 30 Aug 2022
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