Impact of fertiliser, water table, and warming on celery yield and CO2 and CH4 emissions from fenland agricultural peat

An optimized water table depth detected for mitigating global warming potential of greenhouse gas emissions in wetland of Qinghai-Tibetan Plateau

Climate change and human activities have intensified variations of water table depth (WTD) in wetlands around the world, which may strongly affect greenhouse gas emissions. Here, we analyzed how emissions of CO2, CH4, and N2O from the Zoige wetland on the Qinghai-Tibetan Plateau (QTP) vary with the WTD. Our data indicate that the wetland shows net positive global warming potential (11.72 tCO2-e ha-1 yr-1), and its emissions of greenhouse gases are driven primarily by WTD. Our analysis suggests that an optimal WTD exists, which at our study site was approximately 18 cm, for mitigating increases in global warming potential from the wetland. Our study provides insights into how climate change and human acitivies affect greenhouse gas emissions from alpine wetlands, and they suggest that water table management may be effective at mitigating future increases in emissions.

The mediating role of renewable energy, sectoral output and economic growth on greenhouse gas emissions: African regional perspective

Global greenhouse gas emissions are increasing when they should be progressively reducing, given worldwide concerted emissions mitigation efforts and protocols. To effectively tackle emissions to foster a sustainable climate, the situation's complexity needs a sector- and region-specific approach, not a one-stop analysis. We must first understand where the emissions originate-which sectors contribute the most to them. This study employs a panel multiregional framework with advanced econometric techniques accounting for cross-sectional dependence and heterogeneous slope coefficients to analyse GHG emissions (CO2 and CH4), sectoral output, economic growth and renewable energy dynamics across African regions from 2010 to 2019. The empirical findings are as follows: First, regional impacts of the economic sectors vary substantially, reflecting technological and socioeconomic differences leading to heterogeneous environmental patterns in the short and long term. Second, the estimated EKC turning points are uniformly lower, indicating slower environmental impact growth with sectoral development in African regions. Third, trade and urbanization are critical drivers of emissions in most regions and economic sectors, with a more pervasive impact on CO2 emissions than CH4 emissions. Finally, sectoral output imposes differential indirect CO2 and CH4 emissions effects via renewable energy, with East African manufacturing exhibiting the most significant emissions-reduction impact. Disaggregated, regional, and sectoral-specific strategies are recommended for designing green development pathways policies.

Manure properties, soil conditions and managerial factors regulate greenhouse vegetable yield with organic fertilizer application across China

To better understand the responses of vegetable yields in a greenhouse system to organic fertilizer through a quantitative evaluation based on peer-reviewed journal articles and in consideration of environmental managerial factors. We conducted a meta-analysis of 453 paired observations from 68 peer-reviewed journal articles to assess the response of vegetable yields in greenhouse vegetable systems in China to organic fertilization. Compared with the control (no organic fertilizer), organic fertilization significantly increased the yields of vegetables by 44.11% on average. The response of vegetable yields to organic fertilizer tended to increase with the increasing experimental duration. Organic fertilizer application had the greatest potential for leafy vegetables (+76.44%), in loamy soils (+53.94%), at moderate organic fertilizer carbon input levels (+54.13%), and in soils with moderate initial soil total nitrogen levels (+50.89%). Aggregated boosted tree analysis indicated that organic fertilizer carbon inputs, vegetable type and experimental duration were the predominant factors that manipulated the response of vegetable yields to organic fertilizer application. The rational application of farmyard manure would be a promising strategy for increasing vegetable yields in greenhouse vegetable systems in China. Factoring in vegetable type, carbon and nitrogen inputs of organic fertilizer, and soil texture would benefit vegetable yields with the application of organic fertilizer.

Responsible agriculture must adapt to the wetland character of mid-latitude peatlands

Drained, lowland agricultural peatlands are greenhouse gas (GHG) emission hotspots and a large but vulnerable store of irrecoverable carbon. They exhibit soil loss rates of ~2.0 cm yr^-1 and are estimated to account for 32% of global cropland emissions while producing only 1.1% of crop kilocalories. Carbon dioxide emissions account for >80% of their terrestrial GHG emissions and are largely controlled by water table depth. Reducing drainage depths is, therefore, essential for responsible peatland management. Peatland restoration can substantially reduce emissions. However, this may conflict with societal needs to maintain productive use, to protect food security and livelihoods. Wetland agriculture strategies will, therefore, be required to adapt agriculture to the wetland character of peatlands, and balance GHG mitigation against productivity, where halting emissions is not immediately possible. Paludiculture may substantially reduce GHG emissions but will not always be viable in the current economic landscape. Reduced drainage intensity systems may deliver partial reductions in the rate of emissions, with smaller modifications to existing systems. These compromise systems may face fewer hurdles to adoption and minimize environmental harm until societal conditions favour strategies that can halt emissions. Wetland agriculture will face agronomic, socio-economic and water management challenges, and careful implementation will be required. Diversity of values and priorities among stakeholders creates the potential for conflict. Successful implementation will require participatory research approaches and co-creation of workable solutions. Policymakers, private sector funders and researchers have key roles to play but adoption risks would fall predominantly on land managers. Development of a robust wetland agriculture paradigm is essential to deliver resilient production systems and wider environmental benefits. The challenge of responsible use presents an opportunity to rethink peatland management and create thriving, innovative and green wetland landscapes for everyone's future benefit, while making a vital contribution to global climate change mitigation.

Purification of Micro-Polluted Lake Water by Biofortification of Vertical Subsurface Flow Constructed Wetlands in Low-Temperature Season

In this study, a novel lab-scale biofortification-combination system (BCS) of Oenanthe javanica and Bacillus series was developed to improve the treatment ability of vertical subsurface flow constructed wetlands (VSFCW) at low temperatures (0–10 °C). The results showed that BCS-VSFCW overcame the adverse effects of low temperature and achieved the deep removal of nutrients. In addition, the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) by BCS-VSFCW were 38.65%, 28.20%, 18.82%, and 14.57% higher than those of blank control, respectively. During the experiment, Oenanthe javanica and low temperature tolerant Bacillus complemented each other in terms of microbial activity and plant uptake. Therefore, VSFCW combined with Oenanthe javanica and low temperature tolerant Bacillus has a promising future in low temperature (<10 °C) areas of northern China.

Wetland Heterogeneity Determines Methane Emissions: A Pan-Arctic Synthesis

Methane (CH₄) emissions from pan-Arctic wetlands provide a potential positive feedback to global warming. However, the differences in CH₄ emissions across wetland types in these regions have not been well understood. We synthesized approximately 9000 static chamber CH₄ measurements during the growing season from 83 sites across pan-Arctic regions. We highlighted spatial variations of CH₄ emissions corresponding to environmental heterogeneity across wetland types. CH₄ emission is the highest in fens, followed by marshes, bogs, and the lowest in swamps. This gradient is controlled by the water table, soil temperature, and dominant plant functional types and their interactions. The water table position for maximum CH₄ emission is below, close to, and above the ground surface in bogs, marshes/fens, and swamps, respectively. The temperature sensitivity (Q₁₀) of CH₄ emissions varied among different wetland types, ranging from the lowest in swamps to the highest in fens. The interactive impact of temperature and the water table positions on CH₄ emissions are regulated with dominant plant functional types. CH₄ emissions from wetlands dominated by vascular plants rely more on species composition than that dominated by non-vascular plants. Wetlands with greater abundance of graminoids (e.g., fens) have higher CH₄ emissions than tree-dominated wetlands (e.g., swamps). This synthesis emphasizes the role of wetland heterogeneity in determining the strength of CH₄ emissions.

Large historical carbon emissions from cultivated northern peatlands

When a peatland is drained and cultivated, it behaves as a notable source of CO₂ However, we lack temporally and spatially explicit estimates of carbon losses from cultivated peatlands. Using a process-based land surface model that explicitly includes representation of peatland processes, we estimate that northern peatlands converted to croplands emitted 72 Pg C over 850-2010, with 45% of this source having occurred before 1750. This source surpassed the carbon accumulation by high-latitude undisturbed peatlands (36 to 47 Pg C). Carbon losses from the cultivation of northern peatlands are omitted in previous land-use emission assessments. Adding this ignored historical land-use emission implies an 18% larger terrestrial carbon storage since 1750 to close the historical global carbon budget. We also show that carbon emission per unit area decrease with time since drainage, suggesting that time since drainage should be accounted for in inventories to refine land-use emissions from cultivated peatlands.

Methodology for Estimating the Effect of Traffic Flow Management on Fuel Consumption and CO2 Production: A Case Study of Celje, Slovenia

The manuscript discusses the investigation of vehicle flow in a predesignated junction by an appropriate traffic flow management with an effort to minimize fuel consumption, the production of CO2, an essential greenhouse gas (hereinafter referred to as GHG), and related transport costs. The particular research study was undertaken in a frequented junction in the city of Celje, located in the eastern part of Slovenia. The results obtained summarize data on consumed fuel and produced CO2 amounts depending on the type of vehicle, traffic flow mixture, traffic light signal plan, and actual vehicle velocity. These values were calculated separately for three different conditions of traffic flow management. Amounts of fuel consumed were experimentally investigated in real traffic situations, whereas CO2 production was calculated by applying the actual European standard entitled EN 16258:2012 associated with a guideline for measuring emission values, as well as by examining specific traffic flow parameters. The key objective of the manuscript is to present multiple scenarios towards striving to minimize environmental impacts and improve transport operation’s economic consequences when implementing proper traffic flow management. As for crucial findings, we quantified fuel consumption and CO2 emissions based on real data on the number and type of vehicles crossing the examined intersection and traffic light switching intervals. The results show that most of the CO2 was produced while waiting and in the accelerating phase in front of traffic lights, whereby in the running phase through the intersection, significantly less fuel was used. This study represents a mosaic fragment of research addressing endeavors to reduce CO2 production in urban transport. Following the experiments conducted, we can see a notable contribution towards reducing CO2 production with known and tested interventions in the existing transport infrastructure. A procedure embracing individual research steps may be deemed as an approach methodology dealing with traffic flow management with an aim to decrease the environmental and economic impacts of traffic and transport operation; this is where the novelty of the research lies.

Agricultural production and CO2 emissions from two sources in the ECOWAS region: New insights from quantile regression and decomposition analysis

Agriculture being the dominant economic activity of the West African economies is responsible for the most greenhouse gasses emitted in the region. Are there heterogeneous determinants of environmental degradation across low, intermediate, and high CO2 emitters in West Africa? Considering the significance of agriculture, industrial activities, renewable energy consumption and economic growth in West-Africa, this paper investigates the conditional determinants of environmental degradation from two sources (per-capita CO2 emission and CO2 emission from liquid sources) using panel data from 15 ECOWAS countries for the period 1990-2015. The study adopts a panel quantile regression technique with non-additive fixed effects as well as quintile decomposition techniques to explore if the relationship between agricultural and economic factors differs across low, intermediate, and high CO2 emitters and the extent of CO2 emission gap between Low Income Group (LIG) and Lower-Middle Income Groups (LmIG). Results from the mean estimators show that while agricultural production impedes CO₂ emissions from liquid sources, it however increases total emissions implying a shift from mechanized farming to more traditional farming methods and the burning and use of biomass from agricultural produce as an energy source. Estimates of the conditional determinants of environmental degradation vary along the quantiles signifying heterogeneity of the determinants of environmental degradation across, low, intermediate, and high CO2 emitters. Additionally, results emanating from the quantile decomposition procedure show that lower-income West African economies have superseded their lower-middle income counterparts at higher quantiles of CO₂ emissions.

Transcutaneous carbon dioxide measurements in fruits, vegetables and humans: A prospective observational study

BACKGROUND

Transcutaneous carbon dioxide measurement (TcCO2) is frequently used as a surrogate for arterial blood gas sampling in adults and children with critical illness. Data from noninvasive TcCO2 monitoring assists with clinical decisions regarding mechanical ventilation settings, estimation of metabolic consumption and determination of adequate end-organ tissue perfusion.

OBJECTIVES

To report TcCO2 values obtained from various fruits, vegetables and elite critical care medicine specialists.

DESIGN

Prospective, observational, nonblinded cohort study.

SETTINGS

Single-centre, tertiary paediatric referral centre and organic farmers' market.

PARTICIPANTS

Vegetables and fruits included 10 samples of each of the following: red delicious apple (Malus domestica), manzano banana (Musa sapientum), key lime (Citrus aurantiifolia), miniature sweet bell pepper (Capsicum annuum), sweet potato (Ipomoea batatas) and avocado (Persea americana). Ten human controls were studied including a paediatric intensivist, a paediatric inpatient hospital physician, four paediatric resident physicians and four paediatric critical care nurses.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

TcCO2 values for each species and device response times.

RESULTS

TcCO2 readings were measurable in all study species except the sweet potato. Mean ± SD values of TcCO2 for human controls [4.34 ± 0.37 kPa (32.6 ± 2.8 mmHg)] were greater than apples [3.09 ± 0.19 kPa (23.2 ± 1.4 mmHg), P < 0.01], bananas [2.73 ± 0.28 kPa (20.5 ± 2.1 mmHg), P < 0.01] and limes [2.76 ± 0.52 kPa (20.7 ± 3.9 mmHg), P < 0.01] but no different to those of avocados [4.29 ± 0.44 kPa (32.2 ± 3.3 mmHg), P = 0.77] and bell peppers [4.19 ± 1.13 kPa (31.4 ± 8.5 mmHg), P = 0.68]. Transcutaneous response times did not differ between research cohorts and human controls.

CONCLUSION

We found nonroot, nontuberous vegetables to have TcCO2 values similar to that of healthy, human controls. Fruits yield TcCO2 readings, but substantially lower than human controls.