Integrated assessment of carbon footprint and economic profit from paddy fields under microbial decaying agents with diverse water regimes in central China

Abstract Background Interspecific competition is known to be strongest between those species that are both closely related and sympatric. Egrets are colonially nesting wetland birds that often overlap and can therefore be expected to compete in roosting and nesting habitat as well as in diet. According to the niche partitioning hypothesis, it is to be expected that these similar species would show differentiation in at least one of the main niche dimensions to reduce competition. We tested niche partitioning between the colonially nesting Little Egret (Egretta garzetta) and Cattle Egret (Bubulcus ibis) in temporal, spatial and trophic dimensions. Methods Field study was conducted in three mixed egret colonies in Yangxian County, southwest Shaanxi Province, central China. For each nest colony we recorded its spatial location, the height of nesting trees and of nests, the height of roosting trees and of roosting individuals within the trees. We determined the first egg-laying and first hatching dates of the two species. Craw dissection of storm-killed egret nestlings was used to measure the diet. Six transects were surveyed to study foraging habitat selection. Results We found that hatching time of Little Egrets peaked earlier (by about 1 month) than that of Cattle Egrets. Cattle Egrets nested and roosted higher than Little Egrets. The foraging habitats used by Little Egrets were dominated by river banks (73.49%), followed by paddy fields (13.25%) and reservoirs (10.84%), whereas Cattle Egret foraging sites were characterized by grasslands (44.44%), paddy fields (33.33%) and river banks (22.22%). Little Egrets consumed more fishes (65.66%) and Odonata larvae (13.69%) than Cattle Egrets, while Cattle Egrets were found feeding mainly on Coleoptera (29.69%) and Orthoptera (23.29%). Little Egrets preyed on larger mean biomasses of food items than Cattle Egrets. Conclusions Our results confirm the niche partitioning hypothesis as a mechanism for coexistence among ecologically similar species. In two coexisting egret species, niche partitioning is multidimensional, such that the two coexistent species occupy differing ecological space based on all three temporal, spatial and trophic niche dimensions.

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Effects of straw returning levels on carbon footprint and net ecosystem economic benefits from rice-wheat rotation in central China

Environmental Science and Pollution Research ◽

10.1007/s11356-020-10914-w ◽

2020 ◽

Author(s):

Shi-hao Li ◽

Li-jin Guo ◽

Cou-gui Cao ◽

Cheng-fang Li

Keyword(s):

Carbon Footprint ◽

Economic Benefits ◽

Central China

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The Effects of Rape Residue Mulching on Net Global Warming Potential and Greenhouse Gas Intensity from No-Tillage Paddy Fields

The Scientific World JOURNAL ◽

10.1155/2014/198231 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Zhi-Sheng Zhang ◽

Cou-Gui Cao ◽

Li-Jin Guo ◽

Cheng-Fang Li

Keyword(s):

Global Warming ◽

Greenhouse Gas ◽

Oilseed Rape ◽

Global Warming Potential ◽

Growing Season ◽

Central China ◽

Paddy Fields ◽

No Tillage ◽

Greenhouse Gas Intensity ◽

Rice Growing Season

A field experiment was conducted to provide a complete greenhouse gas (GHG) accounting for global warming potential (GWP), net GWP, and greenhouse gas intensity (GHGI) from no-tillage (NT) paddy fields with different amounts of oilseed rape residue mulch (0, 3000, 4000, and 6000 kg dry matter (DM) ha−1) during a rice-growing season after 3 years of oilseed rape-rice cultivation. Residue mulching treatments showed significantly more organic carbon (C) density for the 0–20 cm soil layer at harvesting than no residue treatment. During a rice-growing season, residue mulching treatments sequestered significantly more organic C from 687 kg C ha−1 season−1to 1654 kg C ha−1 season−1than no residue treatment. Residue mulching significantly increased emissions of CO2and N2O but decreased CH4emissions. Residue mulching treatments significantly increased GWP by 9–30% but significantly decreased net GWP by 33–71% and GHGI by 35–72% relative to no residue treatment. These results suggest that agricultural economic viability and GHG mitigation can be achieved simultaneously by residue mulching on NT paddy fields in central China.

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Evaluation of Tourism Eco-efficiency in Yangshuo County from the Perspective of Carbon Footprint

E3S Web of Conferences ◽

10.1051/e3sconf/20185303014 ◽

2018 ◽

Vol 53 ◽

pp. 03014

Author(s):

Xiaoying Han ◽

Jinye Wang ◽

Ning Li

Keyword(s):

Carbon Dioxide ◽

Carbon Footprint ◽

Total Carbon ◽

Input Output ◽

Economic Profit ◽

Model Based

According to the input-output theory, the paper quantitatively analyzes the tourism ecoefficiency of Yangshuo in 2017 by building a tourism eco-efficiency model based on carbon footprint. The research shows that: Firstly, the total carbon footprint of tourism traffic in 2017 is 791.22×106 kg; the total carbon footprint of tourism accommodation is 353.60×106 kg; the total carbon footprint of tourism activities is 123.29×106 kg. Secondly, the 2017 tourism eco-efficiency of the Yangshuo County is 8.05 RMB per kilogram. It refers to the economic profit is 8.05 RMB when 1 kilogram of carbon dioxide is produced, which is relatively efficient compared with other regions. Lastly, the paper makes suggestions with regarding to the optimization of the tourism eco-efficiency.

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A Critical Review on Advancement and Challenges of Biochar Application in Paddy Fields: Environmental and Life Cycle Cost Analysis

Processes ◽

10.3390/pr8101275 ◽

2020 ◽

Vol 8 (10) ◽

pp. 1275 ◽

Cited By ~ 1

Author(s):

Ali Mohammadi ◽

Benyamin Khoshnevisan ◽

G. Venkatesh ◽

Samieh Eskandari

Keyword(s):

Climate Change ◽

Life Cycle ◽

Carbon Footprint ◽

Life Cycle Cost ◽

Agricultural Sector ◽

Economic Benefits ◽

Rice Production ◽

Paddy Fields ◽

Rice Grain ◽

Bottom Line

Paddy fields emit considerable amounts of methane (CH4), which is a potent greenhouse gas (GHG) and, thereby, causes significant environmental impacts, even as they generate wealth and jobs directly in the agricultural sector, and indirectly in the food-processing sector. Application of biochar in rice production systems will not just help to truncate their carbon footprints, but also add to the bottom-line. In this work, the authors have reviewed the literature on climate change, human health, and economic impacts of using organic residues to make biochar for the addition to croplands especially to rice paddy fields. Biochar-bioenergy systems range in scale from small household cook-stoves to large industrial pyrolysis plants. Biochar can be purveyed in different forms—raw, mineral-enriched, or blended with compost. The review of published environmental life cycle assessment (E-LCA) studies showed biochar has the potential to mitigate the carbon footprint of farming systems through a range of mechanisms. The most important factors are the stabilization of the carbon in the biochar and the generation of recoverable energy from pyrolysis gases produced as co-products with biochar as well as decreased fertiliser requirement and enhanced crop productivity. The quantitative review of E-LCA studies concluded that the carbon footprint of rice produced in biochar-treated soil was estimated to range from −1.43 to 2.79 kg CO2-eq per kg rice grain, implying a significant reduction relative to rice produced without a biochar soil amendment. The suppression of soil-methane emission due to the biochar addition is the dominant process with a negative contribution of 40–70% in the climate change mitigation of rice production. The review of the life cycle cost studies on biochar use as an additive in farmlands demonstrated that biochar application can be an economically-feasible approach in some conditions. Strategies like the subsidization of the initial biochar capital cost and assignment of a non-trivial price for carbon abatement in future pricing mechanisms will enhance the economic benefits for the rice farmers.

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