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Topic Review
Pedogenesis
Pedogenesis (from the Greek pedo-, or pedon, meaning 'soil, earth,' and genesis, meaning 'origin, birth') (also termed soil development, soil evolution, soil formation, and soil genesis) is the process of soil formation as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizons, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors. Pedogenesis is studied as a branch of pedology, the study of soil in its natural environment. Other branches of pedology are the study of soil morphology, and soil classification. The study of pedogenesis is important to understanding soil distribution patterns in current (soil geography) and past (paleopedology) geologic periods.
  • 3.1K
  • 03 Nov 2022
Topic Review
Peculiarities of Permafrost Regions
Russia has unique technical and technological experience of gas field development in permafrost regions. One of the most promising regions of potential large gas field discovery is low-population on-land regions of permafrost spread. 
  • 373
  • 21 Jun 2023
Topic Review
Pectin-Based Material for Applications in Water Treatment
Climate change and water are inseparably connected. Extreme weather events cause water to become more scarce, polluted, and erratic than ever. Pectin is a biodegradable polymer, extractable from vegetables, and contains several hydroxyl and carboxyl groups that can easily interact with the contaminant ions. In addition, pectin-based materials can be prepared in different forms (films, hydrogels, or beads) and cross-linked with several agents to change their molecular structure. Consequently, the pectin-based adsorbents can be tuned to remove diverse pollutants such as divalent metals. 
  • 870
  • 22 Mar 2023
Topic Review
PEC Reactors for Water/Wastewater Treatment
Now and in the coming years, how we use and treat water, greywater and wastewater will become more important. A suitably designed photoelectrocatalytic (PEC) reactor is one potential solution. The photoexcitation of suitable semiconducting materials in aqueous environments can lead to the production of reactive oxygen species (ROS). ROS can inactivate microorganisms and degrade a range of chemical compounds. In the case of heterogeneous photocatalysis, semiconducting materials may suffer from fast recombination of electron–hole pairs and require post-treatment to separate the photocatalyst when a suspension system is used. To reduce recombination and improve the rate of degradation, an externally applied electrical bias can be used where the semiconducting material is immobilised onto an electrically conducive support and connected to a counter electrode. These electrochemically assisted photocatalytic systems have been termed “photoelectrocatalytic” (PEC). The term is stated in the IUPAC Recommendations 2011 as “electrochemically assisted photocatalysis. The role of the photocatalyst is played by a photoelectrode, often a semiconductor”. A short description of photocatalysis is included as it can be beneficial for those unfamiliar with the topic, before moving onto PEC. This entry is adapted from https://doi.org/10.3390/w13091198
  • 2.0K
  • 20 Oct 2021
Topic Review
Peat Processing Technologies and Peat Applications
Peatlands can become valuable resources and greenhouse gas sinks through the use of different management practices. Peatlands provide carbon sequestration; however, they are also among the greatest greenhouse gas emissions sources. Peat is undervalued as a resource in the bioeconomy and innovation—a way that could save costs in peatland management. 
  • 264
  • 11 Mar 2024
Topic Review
PCO2 in Inland Waters
The traditional field-based measurements of carbon dioxide (pCO2) for inland waters are a snapshot of the conditions on a particular site, which might not adequately represent the pCO2 variation of the entire lake. However, these field measurements can be used in the pCO2 remote sensing modeling and verification. By focusing on inland waters (including lakes, reservoirs, rivers, and streams), this paper reviews the temporal and spatial variability of pCO2 based on published data. The results indicate the significant daily and seasonal variations in pCO2 in lakes. 
  • 464
  • 31 Jan 2022
Topic Review
Payment for Ecosystem Services
Payment for ecosystem services (PES) is a market-based policy approach intended to foster land use practices, such as forest conservation or restoration, that protect and improve the social benefits from healthy, functioning ecosystems. While PES programs are used globally, they are an especially prominent environmental policy tool in Latin America, where the vast majority are payment for hydrological services (PHS) programs. PHS programs incentivize the conservation and restoration of ecosystems associated with water production and clean water for clearly defined water users, such as household water users, industries and farmers. As a market mechanism, PHS approaches involve a transactional relationship between upstream water producers and downstream water users who are connected by a shared watershed.
  • 485
  • 22 Nov 2021
Topic Review
Past Developments of Carpathian Forests
The Carpathians are the second largest mountain range in Europe and provide multiple ecosystem services of enormous regional importance. The Carpathians belong to seven Central and Eastern European countries (Czech Republic, Slovakia, Poland, Hungary, Ukraine, Romania, and Serbia), whose share of forest land is among the lowest in Europe (27%). With a total area of 9.92 million hectares, Carpathian forests constitute over 70% of the total forested land in Slovakia and Romania, with Romania alone harboring more than 45% of all Carpathian forests. Most of the Carpathian forests are dominated by European beech (Fagus sylvatica), Norway spruce (Picea abies), oak (Quercus robur, Quercus petraea), and silver fir (Abies alba) stands, covering over 70% of the altitudinal range (with the highest point being Gerlachovský štít, 2655 m a.s.l., in the Slovakian Tatra Mountains). The Carpathian Mountains were characterized in terms of their forests in the period starting from Holocene deglaciation. Climate fluctuations and human activities have led to substantial changes in forest systems, and anthropogenic activities, such as logging, fire activities, and grazing, have shaped the distribution and structure of present-day Carpathian forests. The rapid climate change in recent decades adds uncertainty to the future development of these forest systems.
  • 178
  • 17 Jan 2024
Topic Review
Past and Future of Permafrost Monitoring
Changes in the thermal state of permafrost under the influence of climatic variations have occurred over the years, but have not reached their maximum. This circumstance significantly increases the risks in fuel and energy complex stability. Everywhere in the Russian Arctic, there is a loss of the bearing capacity in the bases of buildings and structures. The vast majority of the permafrost data are outdated and need to be actualized in the formation of a unified monitoring system. The development of the fuel and energy complex in the Russian Arctic complements the impact of background climate change. As a result of the joint effect of climate warming and large-scale man-made impacts on permafrost, a cumulative effect arises. Its consequences critically accelerate the loss of the stability of frozen foundations, which leads to major accidents of natural–technical systems.
  • 392
  • 26 May 2022
Topic Review
Passenger Cars Driven on Hilly Roads in Austria
Previous studies of road or railway infrastructures have shown that traffic emissions outweigh the environmental impacts of the product stage and construction stage over the entire life cycle. Traffic usage is therefore the main emitter over the life cycle (A1–C4). Due to the small number of sustainability assessment systems, the question of how to consider traffic emissions in detail in an integral life cycle assessment has arisen.
  • 131
  • 01 Feb 2024
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