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Prairie Pothole wetlands have large temporal changes in water status. The wetlands are often flooded, with water above the soil surface during the early growing season, while becoming dry during the later growing season or for years under strong drought. We used the eddy covariance technique to assess the potential for ecosystem carbon sequestration as a natural climate solution in a large Prairie Pothole wetland in southern Alberta (Frank Lake wetland complex) that was dominated by the emergent macrophyte, Schoenoplectus acutus L. (bulrush). We made ecosystem-scale measurements of CO2 and CH4 exchange over two growing seasons during a time-period with environmental conditions that were warmer and drier than the climate normal. In particular, the study was conducted while the wetland had been experiencing a decade-long drought based on the Standardized Precipitation Evapotranspiration Index. To provide perspective on the longer-term temporal variability of ecosystem carbon exchange processes, we also used LandSat NDVI measurements of vegetation greenness, calibrated with eddy covariance measurements of ecosystem CO2 exchange during 2022-23, to estimate carbon sequestration capacity during 1984-2023, a period that included several wet-dry cycles. Our measured growing season-integrated net CO2 uptake values were 47 and 70 g C m-2 season-1 in 2022 and 2023, respectively. Including the measured low methane emissions (converted to CO2 equivalents based on a Sustained Global Warming Potential) only changed the net sink to 40 and 67 g C m-2 season-1 in 2022 and 2023, respectively. Despite drought conditions over the last decade, measured ecosystem carbon sequestration values were close to average values during 1984-2023, based on NDVI measurements and model carbon flux calculations. Our results demonstrated net carbon sequestration as a natural climate solution in a Prairie Pothole wetland, even during a time-period that was not expected to be favourable for carbon sequestration because of the drought conditions.

期刊论文 2025-06-15 DOI: 10.1016/j.agrformet.2025.110594 ISSN: 0168-1923

River riparian basins play a crucial role in mitigating greenhouse gas (GHG) emissions through carbon sequestration and nitrogen sinks. However, increased ecological stresses led to the release of CO2, CH4 and N2O. This study aimed to investigate how extreme temperatures, water levels, moisture content, land use changes and soil composition influence GHG emissions in the riparian corridor and to recommend mitigation techniques. It was carried out at the Yangtze River Riparian zone, China, using soil column testing. It used soil column testing. The results showed that extreme temperatures caused the highest emissions of CO2 (29-45%), CH4 (24-43%) and N2O (27-33%). This was due to increased soil temperatures and accelerated organic carbon/nitrogen decomposition. Conversely, control and wet-dry cycles absorbed CO2 (1-3%), CH4 (3-10%) and N2O (1-21%) by improving soil aeration, increased oxygen availability, soil structure, stable water table and low temperature change. Grasses in riparian areas also improved carbon sinks. Highest water levels had lowest gas concentrations and emissions due to low oxygen level. Adaptive wet-dry cycles, grass cover and better water table management can restore riparian areas, maintain soil moisture, balance soil carbon/nitrogen levels and mitigate climate change by improving soil quality. Dissolved organic matter fluorescence (DOMFluor) components are essential for soil carbon dynamics, aquatic biome safety, nutrient cycling and ecological balance in riparian zones. The study recommends implementing restoration practices, managing soil moisture, afforestation, regulating temperature and monitoring water tables to mitigate GHG emissions and address climate change. Future policies should focus on promoting resilient land use and ecosystems.

期刊论文 2025-04-01 DOI: 10.1002/eco.70033 ISSN: 1936-0584

Currently, there is a growing concern for human health with the rise of environmental pollution. Water contamination and health problems had been understood. Sanitation-related health issues have been overcome in the greater part of the world. Progressive industrialization has caused a number of new pollutants in water and in the atmosphere. It is a growing concern for the human health, especially upon the reproductive health. Current researchers provide a strong association between the rising concentrations of ambient pollutants and the adverse health impact. Furthermore, the pollutants have the adverse effects upon reproductive health as well. Major concern is for the health of a pregnant woman and her baby. Maternal-fetal inflammatory response due to the pollutants affects the pregnancy outcome adversely. Preterm labor, fetal growth restriction, intrauterine fetal death, and stillbirths have been observed. Varieties of pathological processes including inflammation, endocrine dysfunction, epigenetic changes, oxidative and nitrosative stress, and placental dysfunction have been explained as the biological plausibility. Prospective studies (systematic review and meta-analysis) have established that exposure to particulate matters (PM) and the nanoparticles (NP) leads to excessive oxidative changes to cause DNA mutations, lipid peroxidation and protein oxidation. Progressive industrialization and emergence of heavy metals, micro- (MP) and nanoparticles (NP) in the atmosphere and in water are the cause for concern. However, most of the information is based on studies from industrialized countries. India needs its own country-based study to have the exact idea and to develop the mechanistic pathways for the control.

期刊论文 2025-04-01 DOI: 10.1007/s13224-025-02128-2 ISSN: 0971-9202

The development of soil structure, characterized by fractal geometry, improves plant-rooting development and improves water retention, drainage, and air permeability. However, due to this function to increase fertility, excessive intensive cultivation contributes to environmental load. The amount of nitrogen in rivers in agricultural watersheds is significantly related to the surplus nitrogen in the watershed, and since the nitrogen load increases with the increase in the crop field proportion, it is important to manage the surplus nitrogen in crop field. On the other hand, since wetlands have reduced the surplus nitrogen in the watershed through the purification of nitrate nitrogen in river water, it is possible to reduce the environmental load by optimizing land use. Replacing a part of chemical fertilizer application with organic fertilizer application increased soil organic carbon and contribute to the prevention of global warming without reducing crop yield. In Japanese grasslands, the annual application of 3.5tC ha-1 of compost offset greenhouse gas emissions. Furthermore, the continuous use of compost mitigated soil acidification and suppressed N2O emissions. I investigated the impact of greenhouse gas emissions associated with agricultural development on permafrost and peat soils, which are the world's soil carbon reservoirs. In eastern Siberia, disturbance of taiga forests caused permafrost melting and increased CH4 emissions. Drainage of peatland reduced CH4 emissions, but increased CO2 and N2O emissions due to peat decomposition, which was exacerbated by the application of chemical fertilizers. It was essential to keep the groundwater level at -20 cm to -40 cm to suppress greenhouse gas emissions. Environmental load means that soil health is being damaged. It is necessary to develop agricultural techniques to maintain and restore soil health. In particular, organic matter management can restore soil structure by increasing soil organic matter, and also reduce the amount of chemical fertilizer used, which has the effect of reducing greenhouse gas emissions. On the other hand, excessive continuous use of organic fertilizer can increase nitrogen loads. It has been pointed out that the relationship between cover crops and tillage is also important for organic matter management. Regional research is increasingly essential.

期刊论文 2025-03-27 DOI: 10.1080/00380768.2025.2482940 ISSN: 0038-0768

Beyond flood protection to prevent severe damage, the restored floodplain grassland in Austria provides ecosystem services in terms of carbon balance. Net ecosystem exchange (NEE), gross primary productivity (GPP), and ecosystem respiration (Reco) were quantified by the eddy covariance (EC) method before, during and after a severe flooding event. Our results show that the carbon balance is heavily influenced by water level in the study site. The diurnal variations influenced by various degree from the flood are analysed, showing the average daily GPP of the floodplain grassland in Marchegg dropping from 1.048 g C m-2 day-1 before the flood, down to 0.470 g C m-2 day-1 during the flood. The study demonstrates that the restored floodplain grassland in Marchegg functions as a robust CO2 sink with a cumulative NEE of 38.8 g carbon per m2 over the three-month study period, despite temporary disruptions caused by flooding events. The findings emphasise the considerable potential of floodplain grassland restoration for carbon storage and climate change mitigation, with the new data from the EC station offering valuable insights for future restoration projects. Finally, this supports the adoption of the new EU Nature Restoration Law and the need for restoring wetlands, floodplains and rivers to secure water availability and biodiversity in these unique ecosystems. NBS and more specifically as Soil and Water Bioengineering (SWBE) are methods with ecological advantages and a huge potential for sustainable recreation of nearnatural ecosystems. It is of crucial importance to prove these beneficial effects, and to quantify them transparently in terms of quality assurance and use of resources in a sustainable and eco-friendly way.

期刊论文 2025-02-01 DOI: 10.1016/j.ecoleng.2024.107489 ISSN: 0925-8574

Research in geocryology is currently principally concerned with the effects of climate change on permafrost terrain. The motivations for most of the research are (1) quantification of the anticipated net emissions of CO2 and CH4 from warming and thaw of near-surface permafrost and (2) mitigation of effects on infrastructure of such warming and thaw. Some of the effects, such as increases in ground temperature or active-layer thickness, have been observed for several decades. Landforms that are sensitive to creep deformation are moving more quickly as a result, and Rock Glacier Velocity is now part of the Essential Climate Variable Permafrost of the Global Climate Observing System. Other effects, for example, the occurrence of physical disturbances associated with thawing permafrost, particularly the development of thaw slumps, have noticeably increased since 2010. Still, others, such as erosion of sedimentary permafrost coasts, have accelerated. Geochemical effects in groundwater from trace elements, including contaminants, and those that issue from the release of sediment particles during mass wasting have become evident since 2020. Net release of CO2 and CH4 from thawing permafrost is anticipated within two decades and, worldwide, may reach emissions that are equivalent to a large industrial economy. The most immediate local concerns are for waste disposal pits that were constructed on the premise that permafrost would be an effective and permanent containment medium. This assumption is no longer valid at many contaminated sites. The role of ground ice in conditioning responses to changes in the thermal or hydrological regimes of permafrost has re-emphasized the importance of regional conditions, particularly landscape history, when applying research results to practical problems.

期刊论文 2024-12-10 DOI: 10.1002/ppp.2261 ISSN: 1045-6740

Climate change and land degradation (LD) are some of the most critical challenges for humanity. Land degradation (LD) is the focus of the United Nations (UN) Convention to Combat Desertification (UNCCD) and the UN Sustainable Development Goal (SDG 15: Life on Land). Land degradation is composed of inherent and anthropogenic LD, which are both impacted by inherent soil quality (SQ) and climate. Conventional LD analysis does not take into account inherent SQ because it is not the result of land use/land cover change (LULC), which can be tracked using remote sensing platforms. Furthermore, traditional LD analysis does not link anthropogenic LD to climate change through greenhouse gas (GHG) emissions. This study uses one of the indicators for LD for SDG 15 (15.3.1: Proportion of land that is degraded over the total land area) to demonstrate how to account for inherent SQ in anthropogenic LD with corresponding GHG emissions over time using the state of Arizona (AZ) as a case study. The inherent SQ of AZ is skewed towards low-SQ soils (Entisols: 29.3%, Aridisols: 49.4%), which, when combined with climate, define the inherent LD status. Currently, 8.6% of land in AZ has experienced anthropogenic LD primarily because of developments (urbanization) (42.8%) and agriculture (32.2%). All six soil orders have experienced varying degrees of anthropogenic LD. All land developments in AZ can be linked to damages from LD, with 4862.6 km2 developed, resulting in midpoint losses of 8.7 x 1010 kg of total soil carbon (TSC) and a midpoint social cost of carbon dioxide emissions (SC-CO2) of $14.7B (where B = billion = 109, USD). Arizona was not land degradation neutral (LDN) based on an increase (+9.6%) in the anthropogenic LD overall and an increase in developments (+29.5%) between 2001 and 2021. Considering ongoing climate change impacts in AZ, this increase in urbanization represents reverse climate change adaptation (RCCA) because of the increased population. The state of AZ has 82.0% of the total state area for nature-based solutions (NBS). However, this area is dominated by soils with inherently low SQ (e.g., Entisols, Aridisols, etc.), which complicates efforts for climate change adaptation.

期刊论文 2024-12-01 DOI: 10.3390/cli12120194

Permafrost regions of Qilian Mountains in China are rich in gas hydrate resources. Once greenhouse gases in deep frozen layer are released into the atmosphere during hydrate mining, a series of negative consequences occur. This study aims to evaluate the impact of hydrate thermal exploitation on regional permafrost and carbon budgets based on a multi-physical field coupling simulation. The results indicate that the permeability of the frozen soil is anisotropic, and the low permeability frozen layer can seal the methane gas in the natural state. Heat injection mining of hydrates causes the continuous melting of permafrost and the escape of methane gas, which transforms the regional permafrost from a carbon sink to a carbon source. A higher injection temperature concentrates the heat and causes uneven melting of the upper frozen layer, which provides a dominant channel for methane gas and results in increased methane emissions. However, dense heat injection wells cause more uniform melting of the lower permafrost layer, and the melting zone does not extend to the upper low permeability formation, which cannot provide advantageous channels for methane gas. Therefore, a reasonable and dense number of heat injection wells can reduce the risk of greenhouse gas emissions during hydrate exploitation.

期刊论文 2024-12-01 DOI: 10.1007/s12583-023-1947-5 ISSN: 1674-487X

Context or problem: Most of the research evaluating rice varieties, a major global staple food, for greenhouse gas (GHG) mitigation has been conducted under continuous flooding. However, intermittent irrigation practices are expanding across the globe to address water shortages, which could alter emissions of methane (CH4) compared to nitrous oxide (N2O) for reducing overall global warming potential (GWP). To develop climate-smart rice production systems, it is critical to identify rice varieties that simultaneously reduce CH4 and N2O emissions while maintaining crop productivity under intermittent irrigation. Objective: This study assessed CH4 and N2O emissions, grain yield, and GWP of four rice varieties cultivated under intermittent irrigation in Colombia. Methods: Four common commercial rice varieties were evaluated over two seasons-wet and dry in 2020 and 2021-in two Colombian regions (Tolima and Casanare). Results: Wet-season crop productivity was similar among varieties. However, F68 in Tolima and F-Itagua in Casanare significantly reduced yields in the dry season, likely due to periods of crop water stress. Overall, CH4 emissions and GWP were relatively low due to frequent field drainage events, with GWP ranging from 349 to 4704 kg CO2 equivalents ha(-1). Accordingly, N2O emissions contributed 73% to GWP across locations, as wet-dry cycles can increase N2O emissions, creating a tradeoff for GWP when reducing CH4 through drainage. Varieties F67 in Tolima and F-Itagua in Casanare significantly reduced GWP by 32-61% across seasons, primarily by decreasing N2O rather than CH4 emissions. Conclusions: Rice varietal selection achieved significant GWP mitigation with limited impacts on grain yield, mainly due to reduced N2O emissions under non-continuously flooded irrigation. Implications/significance: This research underscores the critical role of rice varietal selection in addressing global climate-change and water-scarcity challenges, which drive the adoption of intermittent irrigation practices. By focusing on reducing N2O emissions through appropriate variety selection, this study provides valuable insights for rice systems worldwide that are adapting to these pressing environmental challenges.

期刊论文 2024-12-01 DOI: 10.1016/j.jenvman.2024.123376 ISSN: 0301-4797

Potatoes (Solanum tuberosum L.) are the third largest food crop globally and are pivotal for global food security. Widespread N fertilizer waste in potato cultivation has caused diverse environmental issues. This study employed microbial metagenomic sequencing to analyze the causes behind the declining N use efficiency (NUE) and escalating greenhouse gas emissions resulting from excessive N fertilizer application. Addressing N fertilizer inefficiency through breeding has emerged as a viable solution for mitigating overuse in potato cultivation. In this study, transcriptome and metabolome analyses were applied to identify N fertilizer-responsive genes. Metagenomic sequencing revealed that excessive N fertilizer application triggered alterations in the population dynamics of 11 major bacterial phyla, consequently affecting soil microbial functions, particularly N metabolism pathways and bacterial secretion systems. Notably, the enzyme levels associated with NO3 - increased, and those associated with NO and N2O increased. Furthermore, excessive N fertilizer application enhanced soil virulence factors and increased potato susceptibility to diseases. Transcriptome and metabolome sequencing revealed significant impacts of excessive N fertilizer use on lipid and amino acid metabolism pathways. Weighted gene co-expression network analysis (WGCNA) was adopted to identify two genes associated with N fertilizer response: PGSC0003DMG400021157 and PGSC0003DMG400009544.

期刊论文 2024-10-01 DOI: 10.1016/j.ecoenv.2024.116916 ISSN: 0147-6513
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