Based on satellite image data and China's Statistical Yearbooks(2000 to 2014), we estimated the total mass of crop residue burned, and the proportion of residue burned in the field vs.indoors as domestic fuel. The ...Based on satellite image data and China's Statistical Yearbooks(2000 to 2014), we estimated the total mass of crop residue burned, and the proportion of residue burned in the field vs.indoors as domestic fuel. The total emissions of various pollutants from the burning of crop residue were estimated for 2000-2014 using the emission factor method. The results indicate that the total amount of crop residue and average burned mass were 8690.9 Tg and4914.6 Tg, respectively. The total amount of emitted pollutants including CO2, CO, NOx,VOCs, PM(2.5), OC(organic carbon), EC(element carbon) and TC(total carbon) were 4212.4–8440.9 Tg, 192.8–579.4 Tg, 4.8–19.4 Tg, 18.6–61.3 Tg, 18.8–49.7 Tg, 6.7–31.3 Tg, 2.3–4.7 Tg, and8.5–34.1 Tg, respectively. The emissions of pollutants released from crop residue burning were found to be spatially variable, with the burning of crop residue mainly occurring in Northeast, North and South China. In addition, pollutant emissions per unit area(10 km ×10 km) were mostly concentrated in the central and eastern regions of China. Emissions of CO2, NOx, VOCs, OC and TC were mainly from rice straw burning, while burning of corn and wheat residues contributed most to emissions of CO, PM(2.5) and EC. The increased ratio of PM(2.5) emissions from crop residue burning to the total emitted from industry during the study period is attributed to the implementation of strict emissions management policies in Chinese industry. This study also provides baseline data for assessment of the regional atmospheric environment.展开更多
The economic damage to soybean [Glycine max (L.) Merr.] production in the United States attributed to nematodes has increased in recent years. Understanding how soil properties affect nematodes will help to properly m...The economic damage to soybean [Glycine max (L.) Merr.] production in the United States attributed to nematodes has increased in recent years. Understanding how soil properties affect nematodes will help to properly manage agroecosystems to minimize potential nematode damage to soybean crop and the associated economic impact. The objective of this study was to evaluate the relationships between near-surface soil properties and soybean yield and nematode densities across two years (2017 and 2018) in a long-term, wheat (Triticum aestivum L.)-soybean, double-crop production system on a silt-loam soil (Fragiudalfs) in eastern Arkansas. Soybean cyst nematode (SCN;Heterodera glycines Ichinohe) eggs and stage-2 juveniles (J2), lance (Hoplolaimus spp.), lesion (Pratylenchus spp.), spiral (Helicotylenchus spp.), stunt (Tylenchorhynchus spp.), total nematode numbers, and the total genera counts from early in the growing season (July), mid-season (August), and end of the season (October) were generally unrelated with soybean yield. Soybean cyst eggs population density in August was negatively correlated with soil pH (r = -0.92;P ≤ 0.05). Total nematode numbers in July was negatively correlated with silt content (r = -0.23;P ≤ 0.05), soil pH (r = -0.27;P r = -0.24;P ≤ 0.05). Results suggested that soil properties influenced nematode population densities, indicating that nematodes can be at least partially managed and minimized through greater understanding of the variation of select near-surface soil properties in a wheat-soybean, double-crop production system on a silt-loam soil.展开更多
Application of biochar to agricultural soils is effective to sequester atmospheric carbon and improve soil quality, but current pyrolysis and transportation costs are high, making biochar too costly to be used at the ...Application of biochar to agricultural soils is effective to sequester atmospheric carbon and improve soil quality, but current pyrolysis and transportation costs are high, making biochar too costly to be used at the field scale. This study developed a new in-situ technique, burning and soil covering(B-SC), which can be used by farmers for production of biochar with crop residue. In this study,the air-dried feedstocks, elephant grass and corn residue, were burnt in situ for biochar production in the field. After approximately 90% of the leaves were combusted, the burning process was dramatically slowed down by covering the feedstock with soil. The biochar yield averaged 18.0 ± 1.3(n = 15) and 13.7 ± 1.3(n = 10) kg per 100 kg air-dried feedstock for the elephant grass and corn residue,respectively. The biochar properties were suitable for soil improvement. The inputs for biochar production of the B-SC process only included low labor force, open field, feedstock(e.g., grass and crop residue), and simple tools. The operation time for processing 10 kg of the corn residue by an individual farmer was 24.4 ± 4.1 min(n = 10). As compared with the conventional field burning process, the B-SC process drastically shortened the time for biomass burning and generated a significantly lower emission of smoke and thermal energy. This simple technique can be particularly practical and effective for farmers to improve the soils of poor quality in China.展开更多
Annual and monthly-based emission inventories in northern, central and north-eastern provinces in Thailand, where agriculture and related agro-industries are very intensive,were estimated to evaluate the contribution ...Annual and monthly-based emission inventories in northern, central and north-eastern provinces in Thailand, where agriculture and related agro-industries are very intensive,were estimated to evaluate the contribution of agricultural activity, including crop residue burning, forest fires and related agro-industries on air quality monitored in corresponding provinces. The monthly-based emission inventories of air pollutants, or, particulate matter(PM), NOx and SO2, for various agricultural crops were estimated based on information on the level of production of typical crops: rice, corn, sugarcane, cassava, soybeans and potatoes using emission factors and other parameters related to country-specific values taking into account crop type and the local residue burning period. The estimated monthly emission inventory was compared with air monitoring data obtained at monitoring stations operated by the Pollution Control Department, Thailand(PCD) for validating the estimated emission inventory. The agro-industry that has the greatest impact on the regions being evaluated, is the sugar processing industry, which uses sugarcane as a raw material and its residue as fuel for the boiler. The backward trajectory analysis of the air mass arriving at the PCD station was calculated to confirm this influence. For the provinces being evaluated which are located in the upper northern, lower northern and northeast in Thailand, agricultural activities and forest fires were shown to be closely correlated to the ambient PM concentration while their contribution to the production of gaseous pollutants is much less.展开更多
India generates more than 140 million tonnes of surplus crop residue every year In Haryana, the agricultural sector alone produces 24.64 million tonnes of residue annually;of which only 71</span><span style=&...India generates more than 140 million tonnes of surplus crop residue every year In Haryana, the agricultural sector alone produces 24.64 million tonnes of residue annually;of which only 71</span><span style="white-space:nowrap;font-family:Verdana;">%</span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> is consumed in various domestic and commercial activities within the state. The rest of the material is burned causing severe contamination of air with smoke. There is an urgent need to identify suitable and sustainable conversion technologies that are efficient, eco-friendly as well as cost-effective for managing the huge available biomass not only in the state but also in the country. This paper reviews briefly the available crop residue and quantities burned, proposes a scheme to incorporate part of the residue in the field for its fertilizer value. The remaining biomass is harvested for animal feed and the excess is converted to bioenergy and biofuels. Among the developed and developing biofuels, the paper identifies biogas production from biomass for on-farm use. Pelletization is identified as an enabling technology to provide high quality feedstock for conversion to heat/power and in near future to advanced biofuels.展开更多
Soil water retention is a critical aspect of agricultural management, especially in areas such as the Lower Mississippi River Alluvial Valley that face potential water shortages in the near future. Previous studies ha...Soil water retention is a critical aspect of agricultural management, especially in areas such as the Lower Mississippi River Alluvial Valley that face potential water shortages in the near future. Previous studies have linked changes in soil water retention characteristics to agricultural management practices, especially as they affect the accumulation of soil organic matter (SOM). Therefore, the objective of this study was to determine the relationship between soil water potential and gravimetric soil water content in the top 7.5 cm as affected by nitrogen (N) fertilization/residue level (high and low), residue burning (burning and non-burning), tillage (conventional and no-tillage), and irrigation (irrigated and non-irrigated) after 12 complete cropping cycles in a wheat (Triticum aestivum L.)-soybean [Glycine max (L.) Merr.], double-crop production system in the Delta region of eastern Arkansas using soil wetting curves. The soil investigated was a Calloway silt loam (fine silty, mixed, active, thermic Glossaquic Fraglossudalf). The slope characterizing the relationship between the natural logarithm of the soil water potential and the gravimetric soil water content was only affected (P < 0.05) by the N-fertilization/residue-level treatment, while the intercept was unaffected by any field treatment. Averaged across tillage, burning, and irrigation, soil water contents under the high-exceeded those under low-N-fertilization/residue-level treatment at the same water potential, with the greatest differences observed at water contents > 0.12 g·g-1. Understanding the ways in which alternative residue management practices affect soil water retention characteristics is an important component of conserving irrigation water resources.展开更多
Peatland is an important ecosystem in Indonesia.But in almost every dry season,drained peatlands have been subject to detrimental wildfires.As a response,the government has explicitly prohibited the burning of land si...Peatland is an important ecosystem in Indonesia.But in almost every dry season,drained peatlands have been subject to detrimental wildfires.As a response,the government has explicitly prohibited the burning of land since 2016.To clear the land of crop residues and conduct zero burning practices,one alternative method is to utilize the waste biomass to support the cultivation of earthworms(vermiculture).This study examined the quality of liquid fertilizers and compost produced from vermiculture using a completely randomized factorial design,consisting of two treatment factors.The first factor was worm type,with two species used in this research named Lumbricus rubellus and Eudrilus eugeniae.The second factor was the type of feed provided to the worms,comprising no feed(control),vegetable waste,and crop residue waste resulting from zero burning land preparation.The type of feed significantly affected the pH value of the liquid fertilizer produced by the vermiculture but did not significantly affect the nutrient contents(N,P,and K).The combination of the types of earthworms and types of feed significantly affected the pH value of the vermicompost.The combination of worm types and feed types had a significant effect on exchangeable Ca,but not on exchangeable Mg,Na,and K.In combination,green vegetable waste and Lumbricus rubellus produced the greatest effect on soil CEC.However,for Base Saturation,the control(no food)and Eudrilus eugeniae showed the highest value.Types of worms and types of feed had a significant effect on the exchangeable Mg,while the other three parameters made no significant differences.Zero burning waste and Eudrilus eugeniae provide a better exchangeable Ca and Mg.In contrast,no-feeding and Eudrilus eugeniae have a better effect on exchangeable Na and K.Types of worms and types of feed did not significantly affect the weight of worm colonies,but the addition of feed increased the weight of worms with the highest weight resulting from the use of zero burning waste feed.The results showed that crop展开更多
With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high sp...With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer(MODIS) Thermal Anomalies/Fire Daily Level3 Global Product(MOD/MYD14A1). Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO2, CO, CH4,nonmethane volatile organic compounds(NMVOCs), N2O, NOx, NH3, SO2, fine particles(PM2.5),organic carbon(OC), and black carbon(BC) were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June(37%).Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N2O to a high of within ± 169% for NH3.展开更多
基金supported by the Fujian Agriculture and Forestry University Funds for Distinguished Young Scholar(No.xjq201613)the National Natural Science Foundation of China(No.31400552)+1 种基金the International Science and Technology Cooperation Program of Fujian Agriculture and Forestry University(No.KXB16008A)the Asia-Pacific Network for Sustainable Forest Management and Rehabilitation(APFnet/2010/FPF/001)Phase II
文摘Based on satellite image data and China's Statistical Yearbooks(2000 to 2014), we estimated the total mass of crop residue burned, and the proportion of residue burned in the field vs.indoors as domestic fuel. The total emissions of various pollutants from the burning of crop residue were estimated for 2000-2014 using the emission factor method. The results indicate that the total amount of crop residue and average burned mass were 8690.9 Tg and4914.6 Tg, respectively. The total amount of emitted pollutants including CO2, CO, NOx,VOCs, PM(2.5), OC(organic carbon), EC(element carbon) and TC(total carbon) were 4212.4–8440.9 Tg, 192.8–579.4 Tg, 4.8–19.4 Tg, 18.6–61.3 Tg, 18.8–49.7 Tg, 6.7–31.3 Tg, 2.3–4.7 Tg, and8.5–34.1 Tg, respectively. The emissions of pollutants released from crop residue burning were found to be spatially variable, with the burning of crop residue mainly occurring in Northeast, North and South China. In addition, pollutant emissions per unit area(10 km ×10 km) were mostly concentrated in the central and eastern regions of China. Emissions of CO2, NOx, VOCs, OC and TC were mainly from rice straw burning, while burning of corn and wheat residues contributed most to emissions of CO, PM(2.5) and EC. The increased ratio of PM(2.5) emissions from crop residue burning to the total emitted from industry during the study period is attributed to the implementation of strict emissions management policies in Chinese industry. This study also provides baseline data for assessment of the regional atmospheric environment.
文摘The economic damage to soybean [Glycine max (L.) Merr.] production in the United States attributed to nematodes has increased in recent years. Understanding how soil properties affect nematodes will help to properly manage agroecosystems to minimize potential nematode damage to soybean crop and the associated economic impact. The objective of this study was to evaluate the relationships between near-surface soil properties and soybean yield and nematode densities across two years (2017 and 2018) in a long-term, wheat (Triticum aestivum L.)-soybean, double-crop production system on a silt-loam soil (Fragiudalfs) in eastern Arkansas. Soybean cyst nematode (SCN;Heterodera glycines Ichinohe) eggs and stage-2 juveniles (J2), lance (Hoplolaimus spp.), lesion (Pratylenchus spp.), spiral (Helicotylenchus spp.), stunt (Tylenchorhynchus spp.), total nematode numbers, and the total genera counts from early in the growing season (July), mid-season (August), and end of the season (October) were generally unrelated with soybean yield. Soybean cyst eggs population density in August was negatively correlated with soil pH (r = -0.92;P ≤ 0.05). Total nematode numbers in July was negatively correlated with silt content (r = -0.23;P ≤ 0.05), soil pH (r = -0.27;P r = -0.24;P ≤ 0.05). Results suggested that soil properties influenced nematode population densities, indicating that nematodes can be at least partially managed and minimized through greater understanding of the variation of select near-surface soil properties in a wheat-soybean, double-crop production system on a silt-loam soil.
基金supported by the National Natural Science Foundation of China (No. 41271363)
文摘Application of biochar to agricultural soils is effective to sequester atmospheric carbon and improve soil quality, but current pyrolysis and transportation costs are high, making biochar too costly to be used at the field scale. This study developed a new in-situ technique, burning and soil covering(B-SC), which can be used by farmers for production of biochar with crop residue. In this study,the air-dried feedstocks, elephant grass and corn residue, were burnt in situ for biochar production in the field. After approximately 90% of the leaves were combusted, the burning process was dramatically slowed down by covering the feedstock with soil. The biochar yield averaged 18.0 ± 1.3(n = 15) and 13.7 ± 1.3(n = 10) kg per 100 kg air-dried feedstock for the elephant grass and corn residue,respectively. The biochar properties were suitable for soil improvement. The inputs for biochar production of the B-SC process only included low labor force, open field, feedstock(e.g., grass and crop residue), and simple tools. The operation time for processing 10 kg of the corn residue by an individual farmer was 24.4 ± 4.1 min(n = 10). As compared with the conventional field burning process, the B-SC process drastically shortened the time for biomass burning and generated a significantly lower emission of smoke and thermal energy. This simple technique can be particularly practical and effective for farmers to improve the soils of poor quality in China.
基金supported by the Japan Society for the Promotion of Science(JSPS)KAKENHI,253030003
文摘Annual and monthly-based emission inventories in northern, central and north-eastern provinces in Thailand, where agriculture and related agro-industries are very intensive,were estimated to evaluate the contribution of agricultural activity, including crop residue burning, forest fires and related agro-industries on air quality monitored in corresponding provinces. The monthly-based emission inventories of air pollutants, or, particulate matter(PM), NOx and SO2, for various agricultural crops were estimated based on information on the level of production of typical crops: rice, corn, sugarcane, cassava, soybeans and potatoes using emission factors and other parameters related to country-specific values taking into account crop type and the local residue burning period. The estimated monthly emission inventory was compared with air monitoring data obtained at monitoring stations operated by the Pollution Control Department, Thailand(PCD) for validating the estimated emission inventory. The agro-industry that has the greatest impact on the regions being evaluated, is the sugar processing industry, which uses sugarcane as a raw material and its residue as fuel for the boiler. The backward trajectory analysis of the air mass arriving at the PCD station was calculated to confirm this influence. For the provinces being evaluated which are located in the upper northern, lower northern and northeast in Thailand, agricultural activities and forest fires were shown to be closely correlated to the ambient PM concentration while their contribution to the production of gaseous pollutants is much less.
文摘India generates more than 140 million tonnes of surplus crop residue every year In Haryana, the agricultural sector alone produces 24.64 million tonnes of residue annually;of which only 71</span><span style="white-space:nowrap;font-family:Verdana;">%</span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> is consumed in various domestic and commercial activities within the state. The rest of the material is burned causing severe contamination of air with smoke. There is an urgent need to identify suitable and sustainable conversion technologies that are efficient, eco-friendly as well as cost-effective for managing the huge available biomass not only in the state but also in the country. This paper reviews briefly the available crop residue and quantities burned, proposes a scheme to incorporate part of the residue in the field for its fertilizer value. The remaining biomass is harvested for animal feed and the excess is converted to bioenergy and biofuels. Among the developed and developing biofuels, the paper identifies biogas production from biomass for on-farm use. Pelletization is identified as an enabling technology to provide high quality feedstock for conversion to heat/power and in near future to advanced biofuels.
文摘Soil water retention is a critical aspect of agricultural management, especially in areas such as the Lower Mississippi River Alluvial Valley that face potential water shortages in the near future. Previous studies have linked changes in soil water retention characteristics to agricultural management practices, especially as they affect the accumulation of soil organic matter (SOM). Therefore, the objective of this study was to determine the relationship between soil water potential and gravimetric soil water content in the top 7.5 cm as affected by nitrogen (N) fertilization/residue level (high and low), residue burning (burning and non-burning), tillage (conventional and no-tillage), and irrigation (irrigated and non-irrigated) after 12 complete cropping cycles in a wheat (Triticum aestivum L.)-soybean [Glycine max (L.) Merr.], double-crop production system in the Delta region of eastern Arkansas using soil wetting curves. The soil investigated was a Calloway silt loam (fine silty, mixed, active, thermic Glossaquic Fraglossudalf). The slope characterizing the relationship between the natural logarithm of the soil water potential and the gravimetric soil water content was only affected (P < 0.05) by the N-fertilization/residue-level treatment, while the intercept was unaffected by any field treatment. Averaged across tillage, burning, and irrigation, soil water contents under the high-exceeded those under low-N-fertilization/residue-level treatment at the same water potential, with the greatest differences observed at water contents > 0.12 g·g-1. Understanding the ways in which alternative residue management practices affect soil water retention characteristics is an important component of conserving irrigation water resources.
文摘Peatland is an important ecosystem in Indonesia.But in almost every dry season,drained peatlands have been subject to detrimental wildfires.As a response,the government has explicitly prohibited the burning of land since 2016.To clear the land of crop residues and conduct zero burning practices,one alternative method is to utilize the waste biomass to support the cultivation of earthworms(vermiculture).This study examined the quality of liquid fertilizers and compost produced from vermiculture using a completely randomized factorial design,consisting of two treatment factors.The first factor was worm type,with two species used in this research named Lumbricus rubellus and Eudrilus eugeniae.The second factor was the type of feed provided to the worms,comprising no feed(control),vegetable waste,and crop residue waste resulting from zero burning land preparation.The type of feed significantly affected the pH value of the liquid fertilizer produced by the vermiculture but did not significantly affect the nutrient contents(N,P,and K).The combination of the types of earthworms and types of feed significantly affected the pH value of the vermicompost.The combination of worm types and feed types had a significant effect on exchangeable Ca,but not on exchangeable Mg,Na,and K.In combination,green vegetable waste and Lumbricus rubellus produced the greatest effect on soil CEC.However,for Base Saturation,the control(no food)and Eudrilus eugeniae showed the highest value.Types of worms and types of feed had a significant effect on the exchangeable Mg,while the other three parameters made no significant differences.Zero burning waste and Eudrilus eugeniae provide a better exchangeable Ca and Mg.In contrast,no-feeding and Eudrilus eugeniae have a better effect on exchangeable Na and K.Types of worms and types of feed did not significantly affect the weight of worm colonies,but the addition of feed increased the weight of worms with the highest weight resulting from the use of zero burning waste feed.The results showed that crop
基金supported by the Environmental Protection Ministry of China for Research of Characteristics and Controlling Measures of VOCs Emissions from Typical Anthropogenic Sources (No. 2011467003)the Natural Science Foundation key project (grant no. 91544106)
文摘With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer(MODIS) Thermal Anomalies/Fire Daily Level3 Global Product(MOD/MYD14A1). Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO2, CO, CH4,nonmethane volatile organic compounds(NMVOCs), N2O, NOx, NH3, SO2, fine particles(PM2.5),organic carbon(OC), and black carbon(BC) were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June(37%).Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N2O to a high of within ± 169% for NH3.