Field Burning Of Crop Residue Research Articles

A sustainable approach for soil amendment; available plant nutrients in rice straws

The main aim of this study is to estimate the potential of mitigating the soil degradation by the utilization of rice straws, In every crop huge quantity of crop residue is generated along with the food grains. Only small part of the crop residue is used as cattle feed and other applications, significant quantity of these crop residues are either left unutilized or disposed by means of open field burning by the farmers, because other disposal options are not economically viable for the farmers. Consequences of open field burning of crop residues in India are, contribution of particulate matter in the atmosphere, emission of CO2, CO, NH3, NOx, SOx, and smog. On burning of crop residue heat produced is also accounted for the damage of microbes and other nutrients also present on the top layer of the soil, loss of organic carbon; it adversely affects soil fertility and productivity. It has a great economic potential as it contains high carbon content and significant amount of other essential plant nutrients which are required for plant growth. Sun dried rice straw samples were collected and analysed for primary nutrients (C, H, S, N, P2O5 and K2O) required for plant growth. Moisture content was 11.70%, Elemental analysis of paddy straw on dry basis was found C = 36.04%, H = 5.25%, S = 0.28% & N = 0.69% P2O5 = 0.43% and K2O = 0.64% in the kharif season 2021. These elements were quantified by using different advanced analytical techniques.

Feasibility study of prescribed burning for crop residues based on urban air quality assessment.

Open field burning of crop residue has been intentionally prohibited due to the undesired air pollution in urban regions. To better balance the urban environment and agricultural activity, this paper conducted a feasibility study of prescribed burning for crop residues based on air quality assessment in urban regions. Firstly, emission inventories were established using the top-down approach based on designed sub-regional fire as prescribed burning. Subsequently, the air qualities in urban regions were simulated by the coupled Weather Research and Forecasting Model-Community Multi-scale Air Quality Model (WRF-CMAQ) covering different sensitivity experiments. Finally, PM2.5 is selected as the main indicator of air quality, and the feasibility was assessed by controlling the factors influencing the diffusion of pollutants from prescribed burning, including burning ratio, meteorological factors (wind speed and direction), distance from burning area and burning duration. It is revealed that prescribed burning would achieve highly efficient disposal of crop residues under the premise of ensuring the air quality in urban regions by controlling the factors. Results in the study can be further exploited for designing burning scheme for crop residue, which is expected to promote a sustainable development of agriculture and urban environment.

Conservation Agriculture in Maize-based Cropping System of Nepal: A Review

Maize-based cropping system followed by intensive tillage and faulty practices often associated with many negative implications such as the decline of soil organic matter, increase soil erosion by wind/water, lower nutrient-use efficiency, field burning of crop residue, air pollution mainly attributed to the monoculture of intensive conventional production systems leading to global warming and decline in factor productivity. Conservation Agriculture (CA) underlying principles of minimal soil disturbance, soil cover and crop rotation are increasingly recognized as an essential for the sustainability of this cropping system. Therefore, a brief review was done to find out the results its constraints and the possible interventions under a maize-based system of Nepal. Very few works under CA is done so far under maize-based cropping system of Nepal, however, the results are encouraging. There are some constraints in CA technologies promotion, such as scale-neutral agri-machineries, crop residues competition between CA use and livestock feeding, skilled and scientific manpower availability and overcoming the bias or mindset about tillage. CA provide opportunities to reduce the cost of production, improve resource use efficiency, saves water and nutrients and increase yield. There is a need to develop and promote low-cost technologies of CA that can be used effectively in maize based system of hills and Terai.

Can Neural Networks Forecast Open Field Burning of Crop Residue in Regions with Anthropogenic Management and Control? A Case Study in Northeastern China

Open burning is often used to remove crop residue during the harvest season. Despite a series of regulations by the Chinese government, the open burning of crop residue still frequently occurs in China, and the monitoring and forecasting crop fires have become a topic of active research. In this paper, crop fires in Northeastern China were forecasted using an artificial neural network (ANN) based on moderate-resolution imaging spectroradiometer (MODIS) satellite fire data from 2013–2020. Both natural factors (meteorological, soil moisture content, harvest date) and anthropogenic factors were considered. The model’s forecasting accuracy under natural factors reached 77.01% during 2013–2017. When considering the influence of anthropogenic management and control policies, such as the straw open burning prohibition areas in Jilin Province, the accuracy of the forecast results for 2020 was reduced to 60%. Although the forecasting accuracy was lower than for natural factors, the relative error between the observed fire points and the back propagation neural network (BPNN) forecasting results was acceptable. In terms of influencing factors, air pressure, the change in soil moisture content in a 24 h period and the daily soil moisture content were significantly correlated with open burning. The results of this study improve our ability to forecast agricultural fires and provide a scientific framework for regional prevention and control of crop residue burning.

Integrated nutrient management - promising way to reduce carbon dioxide and methane emission in flooded rice ecosystem: A review

Climate change is an inevitable ruling issue caused by the increasing concentration of greenhouse gases (GHG’s) in the atmosphere worldwide. It will have a considerable impact on agriculture and its related fields like live stocks and fisheries. In India, the main sectors contributing to these emissions are industry, agriculture and waste, with a total emission of 334 MT CO2 eq. Besides, the major sources in agriculture are enteric fermentation (63.4%), rice cultivation (20.9%), agricultural soils (13.0%), manure management (2.4%) and on-field burning is the crop residue (2.0%). Thus, the crop productivity sector (rice cultivation, soil and field burning of crop residues) contributes 35.9% to the total emission from agriculture. Therefore, reducing GHG emissions and enhancing the C sequestration in soil and biomass has become challenging. However, the total GHG’s emission from all sectors of the country has decreased from 33% in 1970 to 18% in 2010. Cutting off GHGs emission from agriculture can be achieved by sequestering C and reducing methane emissions(CH4) and carbon dioxide(CO2) through various soil and crop management strategies. Integrated nutrient management (INM) practice ensures the Soil –plant –atmospheric continuum (SPAC) in a promising way, reducing the GHGs emission by sequestering more carbon to soil than emissions. A studious prominent INM solution can be identified to develop a mitigation strategy that helps in climate change adaptation and sustains soil health through soil carbon sequestration.

In situ decomposition of crop residues using lignocellulolytic microbial consortia: a viable alternative to residue burning.

Open field burning of crop residue causes severe air pollution and greenhouse gas emission contributing to global warming. In order to seek an alternative, the current study was initiated to explore the prospective of lignocellulolytic microbes to expedite in situ decomposition of crop residues. Field trials on farmers' field were conducted in the state of Haryana and Maharashtra, to target the burning of rice and wheat residue and sugarcane trash, respectively. A comparative study among crop residue removal (CRR), crop residue burning (CRB) and in situ decomposition of crop residues (IND) revealed that IND of rice and wheat residues took 30days whereas IND of sugarcane trash took 45days. The decomposition status was assessed by determining the initial and final lignin to cellulose ratio which increased significantly from 0.23 to 0.25, 0.21 to 0.23 and 0.24 to 0.27 for rice, wheat residues and sugarcane trash, respectively. No yield loss was noticed in IND for both rice-wheat system and sugarcane-based system; rather IND showed relatively better crop yield as well as soil health parameters than CRB and CRR. Furthermore, the environmental impact assessment of residue burning indicated a substantial loss of nutrients (28-31, 23-25 and 51-77kgha-1 of N+P2O5+K2O for rice, wheat and sugarcane residue) as well as the emission of pollutants to the atmosphere. However, more field trials, as well as refinement of the technology, are warranted to validate and establish the positive potential of in situ decomposition of crop residue to make it a successful solution against the crop residue burning.

Crop residue its impact and management

Residue managing task is growing dare for sustainable advancement of Indian agriculture science and environmental protection usually in Indo-Gangetic plains. Farming societies need awareness regarding the harmful impacts of field burning of crop residues and the significance of crop residues combination in the soil for conserving supportable agricultural production and reduction of the cost of production by adopting alternatives. Proper collection and management of crop residue are needed to use it as retention, a substrate for mushroom cultivation, incorporation in the fields, bio-energy fuel, biochar production, etc. The crop residues can be used livestock feed, fuel, industrial raw material, compost precursor, etc. and also are of great economic as well as significant value. The resource-conserving technologies which involve zero-tillage, usage of the happy seeder, bed planting, polyculture with innovations in residue management, the participation of farming communities, and support of political and Govt. Organizations and NGOs are the best probable replacements to conservative energy and input-intensive farming.

Energy use efficiency of crop residue management for sustainable energy and agriculture conservation in NW India

In the Indo-Gangetic plains of South Asia, the triple challenges of diminishing farm profitability, deteriorating natural resources and energy deficits threaten conventional agricultural sustainability. This threat is intensified by the open field burning of crop residues that not only squander an indirect renewable source of energy but also impair the soil and environment quality. The crop residues can be used as organic manure by retaining the residues as mulch in the field. After a long term (5-yrs) study, it was concluded that crop residues biomass contributed maximum (∼79%) in total input energy (1,68,556 MJ ha−1) in conservation agriculture (CA) based systems, however fertilizer application (non-renewable energy source) contributed maximum (∼50%) to the total energy (40,636 MJ ha−1) in conventional tillage (CT) based maize-wheat cropping system.CA based maize systems recorded higher input energy and energy intensiveness by 23 and 57% respectively, and recorded almost 44% lower energy use efficiency and energy productivity compared to CT based maize systems. On 5 years average basis, Zero tillage based maize-wheat-mungbean with nutrient expert cropping system(ZT/MWMb + NE) utilized 351% more input energy, which resulted in25%higher output energy and 363% higher EI compared to CT/MW (40,636 MJ ha−1, 4,20,197 MJ ha−1, 39.60 MJ USD−1).

Molecular characteristics and diurnal variations of organic aerosols at a rural site in the North China Plain with implications for the influence of regional biomass burning

Abstract. Field burning of crop residue in early summer releases a large amount of pollutants into the atmosphere with significant impacts on the air quality and aerosol properties in the North China Plain (NCP). In order to investigate the influence of this regional anthropogenic activity on molecular characteristics of organic aerosols, PM2.5 filter samples were collected with a 3 h interval at a rural site of NCP from 10 to 25 June 2013 and analyzed for more than 100 organic tracer compounds, including both primary (n-alkanes, fatty acids/alcohols, sugar compounds, polycyclic aromatic hydrocarbons, hopanes, and phthalate esters) and secondary organic aerosol (SOA) tracers (phthalic acids, isoprene-, α-/β-pinene, β-caryophyllene, and toluene-derived products), as well as organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC). Total concentrations of the measured organics ranged from 177 to 6248 ng m−3 (mean 1806±1308 ng m−3) during the study period, most of which were contributed by sugar compounds, followed by fatty acids and fatty alcohols. Levoglucosan (240±288 ng m−3) was the most abundant single compound and strongly correlated with OC and WSOC, suggesting that biomass burning (BB) is an important source of summertime organic aerosols in this rural region. Based on the analysis of fire spots and backward trajectories of air masses, two representative periods were classified, which are (1) Period 1 (P1), 13 June 21:00–16 June at 15:00 CST (China Standard Time), when air masses were uniformly distributed from the southeast part of NCP, where intensive open-field biomass burning occurred; and (2) Period 2 (P2), 22 June at 12:00 to 24 June at 06:00 CST, which is representative of local emission. Nearly all the measured PM components showed much higher concentrations in P1 than in P2. Although n-alkanes, fatty acids, and fatty alcohols presented similar temporal–diurnal variations as those of levoglucosan throughout the entire period, their molecular distributions were more dominated by high molecular weight (HMW) compounds in P1, demonstrating an enhanced contribution from BB emissions. In contrast, intensive BB emission in P1 seems to have limited influence on the concentrations of polycyclic aromatic hydrocarbons (PAHs), hopanes, and phthalate esters. Both 3-hydroxyglutaric acid and β-caryophyllinic acid showed strong linearly correlations with levoglucosan (R2=0.72 and 0.80, respectively), indicating that BB is also an important source for terpene-derived SOA formation. A tracer-based method was used to estimate the distributions of biomass-burning OC, fungal-spore OC, and secondary organic carbon (SOC) derived from isoprene, α-/β-pinene, β-caryophyllene, and toluene in the different periods. The results showed that the contribution of biomass-burning OC to total OC in P1 (27.6 %) was 1.7 times that in P2 (17.1 %). However, the contribution of SOC from oxidation of the four kinds of volatile organic compounds (VOCs) increased slightly from 16.3 % in P1 to 21.1 % in P2.

Crop residue management in rice–wheat cropping system for resource conservation and environmental protection in north-western India

Residue management is the emerging challenge for sustainable growth of Indian agriculture and environmental protection mainly in Indo-Gangetic Plains (IGP). Out of 620 MT crop residues produced annually in the country, 234 MT is surplus and 30% of it is contributed by rice and wheat. Approximately 16% of total crop residue being burnt, 62% is contributed by rice and wheat. At present, we do not have any viable and systematic approach to deal with crop residues or adoption rate is poor. Therefore, the farmers in majority burn rice residues in the field, which leads to huge nutrient loss besides deteriorating environment and human health. Major forces enforcing residue burning are combinde harvesting, lack of traditional use of crop residues, intensive cropping system and non-availability of buyers for rice straw. Farmers need to get clear fields within short time frame at any cost to ensure the timely sowing of next crop (wheat) without any hindrance in farm operation offered by loose straw. It takes time to manage loose straw by mechanical operation to ensure smooth sowing of next crop in standing stubble which compile farmers to go for straw burning. Field burning of crop residue (FBCR) was not given much attention by policy makers in last two decades because it was at a small scale, but nowadays, it is counted as the serious agricultural pollutant, which is directly impacting environment and human health and causes global warming as burning produces greenhouse gases. In the harvesting season Punjab, Haryana, Western Uttar Pradesh and Delhi face heavy smog problem because of this unhealthy practice and soil fertility is also deprived. In the IGP, rice–wheat is a major cropping system and both crops produce a lot of surplus residues which is ultimately disposed of by burning in the field particularly the rice residues. Nowadays, government and courts have zero tolerance against FBCR. Strict laws including heavy penalties and imprisonment against offenders are already in place. In the absence of suitable and economical viable alternative, farmers are still compelled to follow this practice as it is otherwise a big headache for farmers. We need to manage on-farm and post-harvest management of crop residues either by modification in machineries, educating farmers, adjustment in the cropping system and utilizing rice straw in industry and power generation. In this review, efforts have been made to cover major aspects related to rice residue management in rice–wheat cropping system (RWCS) of India.

Non-CO2 Greenhouse Gas Emissions from Field Burning of Crop Residues in the Philippines: 1990-2015

crop residue, open burning, non-CO₂ emissions, inventory, philippines

Biomass-gasification-based atmospheric water harvesting in India

Biomass from crop residue remains an underutilized and inexpensive energy resource around the world. Inadequate supply chain management forces farmers to resort to field burning of crop residue, resulting in environmental, health, and economic issues. In this study, we conceptualize a novel approach for biomass utilization which jointly addresses the common and often concurrent issues of energy, environment, and water. We propose to use the thermal energy from the combustion of the producer gas obtained from biomass gasification to power an off-the-grid refrigeration system which can condense moisture from air. We conduct a detailed thermodynamic analysis of vapor-adsorption cycle-based atmospheric water harvesting (AWH) system to develop an integrated modeling framework. We use the ambient weather data to report that the biomass-powered AWH can condense 800–1200 L of water per 1000 kg of biomass. Based on the local population and biomass availability, this can meet up to 10–12% of the potable water requirements in certain states of India. We also discuss the immediate challenges underlying this waste-to-value concept. Finally, we discuss that the proposition to jointly address energy, water, and the environment issues may motivate key paradigm shifts in policies required for practical implementation of this technology.

GHG AND AEROSOL EMISSION FROM FIRE PIXEL DURING CROP RESIDUE BURNING UNDER RICE AND WHEAT CROPPING SYSTEMS IN NORTH-WEST INDIA

Abstract. Emission of smoke and aerosol from open field burning of crop residue is a long-standing subject matter of atmospheric pollution. In this study, we proposed a new approach of estimating fuel load in the fire pixels and corresponding emissions of selected GHGs and aerosols i.e. CO2, CO, NO2, SO2, and total particulate matter (TPM) due to burning of crop residue under rice and wheat cropping systems in Punjab in north-west India from 2002 to 2012. In contrasts to the conventional method that uses RPR ratio to estimate the biomass, fuel load in the fire pixels was estimated as a function of enhanced vegetation index (EVI). MODIS fire products were used to detect the fire pixels during harvesting seasons of rice and wheat. Based on the field measurements, fuel load in the fire pixels were modelled as a function of average EVI using second order polynomial regression. Average EVI for rice and wheat crops that were extracted through Fourier transformation were computed from MODIS time series 16 day EVI composites. About 23 % of net shown area (NSA) during rice and 11 % during wheat harvesting seasons are affected by field burning. The computed average fuel loads are 11.32 t/ha (±17.4) during rice and 10.89 t/ha (±8.7) during wheat harvesting seasons. Calculated average total emissions of CO2, CO, NO2, SO2 and TPM were 8108.41, 657.85, 8.10, 4.10, and 133.21 Gg during rice straw burning and 6896.85, 625.09, 1.42, 1.77, and 57.55 Gg during wheat burning. Comparison of estimated values shows better agreement with the previous concurrent estimations. The method, however, shows its efficiency parallel to the conventional method of estimation of fuel load and related pollutant emissions.

Emission Inventory of Volatile Organic Compounds from Field Burning of Crop Residues in Hubei Province, China

Crop residues combustion is an important anthropogenic sources of volatile organic compounds (VOCs) in China.Emissions of VOCs from crop residues combustion significantly affect climate forcing and human health. A reliable estimation of VOCs emission from the source is the important prerequisite for emission impact assessment and control strategy in the urban or regional areas. VOCs emissions from crop residues combustion in Hubei Province, China and the districts were estimated by factor analysis method, which was based on the yield of major farm crops in the period of 2010. Moreover, Cultivated-land emission intensity (Ic) and Regional emission intensity (Ir) were also calculated. VOCs Emissions from crop residues combustion in Hubei Province were about 80, 000 t in 2010; Ic and Ir were 2.431 t•km-2 and 0.434 t•km-2 respectively; Huanggang, Jingzhou, Xiangyang, Jingmen and Xiaogan had the top five of VOCs Emissions from crop residues combustion. Ic and Ir of Qianjiang, Xiaotao and Ezhou were all more than the average; Ic of Suizhou and Ir of Tianmen were also above the average. 10 city mentioned above should be draw attention as the priority control area. Furthermore, crop residues utilization according to agricultural cyclic economy is a feasible way to cope with the environmental problem of biomass combustion.

Assessment of Nitrous Oxide (N2O) Emissions from Farmland in 2011 with IPCC Guideline Methodology

This study was conducted to assess <TEX>$N_2O$</TEX> emissions in agricultural soils of Korea under the 1996 IPCC (Intergovernmental Panel on Climate Change) methodology. <TEX>$N_2O$</TEX> emissions in agricultural soils were calculated the sum of direct emission and indirect emission by the N sources and emissions by field burning of crop residues. <TEX>$N_2O$</TEX> emission was highest in animal manure as 1,547 <TEX>$CO_2$</TEX>-eq Gg. Indirect emissions by atmospheric deposition and leaching and runoff were 1,463 and 1,753 <TEX>$CO_2$</TEX>-eq Gg, respectively. <TEX>$N_2O$</TEX> emission by field burning of crop residues was highest in pepper due to the residue/crop ratio and field burning ratio.

2006 IPCC 가이드라인을 적용한 지자체별 경종부문 온실가스 배출량 평가

This study was conducted to estimate the greenhouse gas emissions on local government levels from 1990 to 2010 using 2006 IPCC guideline methodology. To calculate greenhouse gas emissions based on the 16 local governments, emission factor and scaling factor were used with default value and activity data came from the food, agricultural, forestry and fisheries statistical yearbook of MIFAFF (Ministry for Food, Agriculture, Forestry, and Fisheries). The total emissions in crop sector gradually decreased from 1990 to 2010 due to a decline in agricultural land and nitrogen fertilizer usage. The annual average emission of greenhouse gas was the highest in Jeonnam (JN) with 1,698 Gg -eq and following Chungnam (CN), Gyungbuk (GB), Jeonbuk (JB) and Gyunggi (GG). The sum of top-six locals emission had occupied 83.4% of the total emission in cropland sector. The annual average emissions in 1990 by applying 2006 IPCC guideline were approximately 43% less than the national greenhouse gas inventory by 1996 IPCC guideline. Jeonnam (JN) province occupied also the highest results of greenhouse gas emission estimated by gas types (methane, nitrous oxide and carbon dioxide) and emission sources such as rice cultivation, agricultural soil, field burning of crop residue and urea fertilizer.

Characterization of submicron aerosols at a rural site in Pearl River Delta of China using an Aerodyne High-Resolution Aerosol Mass Spectrometer

Abstract. The Pearl River Delta (PRD) region in South China is one of the most economically developed regions in China, but it is also noted for its severe air pollution due to industrial/metropolitan emissions. In order to continuously improve the understanding and quantification of air pollution in this region, an intensive campaign was executed in PRD during October–November 2008. Here, we report and analyze Aerodyne High-Resolution Aerosol Mass Spectrometer measurements at Kaiping, a rural site downwind of the highly-polluted central PRD area, to characterize the general features of submicron particulate pollution in the regional air. The mean measured PMsub&gt;1 mass concentration was 33.1±18.1 μg m−3 during the campaign and composed of organic matter (33.8%), sulfate (33.7%), ammonium (14.0%), nitrate (10.7%), black carbon (6.7%), and chloride (1.1%), which is characterized by high fractions of inorganic ions due to huge emissions of SO2 and NOx in PRD. The average size distributions of the species (except BC) were all dominated by an accumulation mode peaking at ~450 nm in vacuum aerodynamic diameter. Calculations based on high-resolution organic mass spectra indicate that C, H, O, and N on average contributed 56.6, 7.0, 35.1, and 1.3% to the total organic mass, respectively, corresponding to an organic matter mass to organic carbon mass ratio (OM/OC) of 1.77±0.08. Based on the high-resolution organic mass spectral dataset observed, Positive Matrix Factorization (PMF) analysis differentiated the organic aerosol into three components, i.e., biomass burning (BBOA) and two oxygenated (LV-OOA and SV-OOA) organic aerosols, which on average accounted for 24.5, 39.6 and 35.8% of the total organic mass, respectively. The BBOA showed strong features of biomass burning emissions and has been mainly attributed to the open field burning of crop residues after the harvest in PRD rural areas. The LV-OOA and SV-OOA were found to correspond to more aged (and thus less-volatile) and fresher (and semi-volatile) secondary organic aerosol (SOA), respectively. Analysis of meteorological influence supported that regional transport from the central PRD area was the major origin of the PM1 observed at the Kaiping site.

Characterization of particulate matter emission from open burning of rice straw

Emission from field burning of crop residue, a common practice in many parts of the world today, has potential effects on air quality, atmosphere and climate. This study provides a comprehensive size and compositional characterization of particulate matter (PM) emission from rice straw (RS) burning using both in situ experiments (11 spread field burning) and laboratory hood experiments (3 pile and 6 spread burning) that were conducted during 2003-2006 in Thailand. The carbon balance and emission ratio method was used to determine PM emission factors (EF) in the field experiments. The obtained EFs varied from field to hood experiments reflecting multiple factors affecting combustion and emission. In the hood experiments, EFs were found to be depending on the burning types (spread or pile), moisture content and the combustion efficiency. In addition, in the field experiments, burning rate and EF were also influenced by weather conditions, i.e. wind. Hood pile burning produced significantly higher EF (20±8 g kg(-1) RS) than hood spread burning (4.7±2.2 g kg(-1) RS). The majority of PM emitted from the field burning was PM(2.5) with EF of 5.1±0.7 g m(-2) or 8.3±2.7 g kg(-1) RS burned. The coarse PM fraction (PM(10-2.5)) was mainly generated by fire attention activities and was relatively small, hence the resulting EF of PM(10) (9.4±3.5 g kg(-1) RS) was not significantly higher than PM(2.5). PM size distribution was measured across 8 size ranges (from <0.4 μm to >9.0 μm). The largest fractions of PM, EC and OC were associated with PM(1.1). The most significant components in PM(2.5) and PM(10) include OC, water soluble ions and levoglucosan. Relative abundance of some methoxyphenols (e.g., acetylsyringone), PAHs (e.g., fluoranthene and pyrene), organochlorine pesticides and PCBs may also serve as additional signatures for the PM emission. Presence of these toxic compounds in PM of burning smoke increases the potential toxic effects of the emission. For illustration, an estimation of the annual RS field burning in Thailand was made using the obtained in situ field burning EFs and preliminary burning activity data.

Assessment of trace gases, carbon and nitrogen emissions from field burning of agricultural residues in India

Field burning of crop residue (FBCR) is becoming a growing environmental concern in developing countries. In this instance, a comprehensive crop-wise and spatially distributed study on the FBCR emissions from India for the period 1980 through 2010 have been undertaken, that covers: residue generation, its types, use pattern, and estimates of carbon, nitrogen, CH4, CO, N2O and NOX emissions; along with associated uncertainties. FBCR contributed about 44 and 14% of the non-biofuel biomass and total biomass burning, respectively in India in the year 2000. The total dry residue generated are estimated as 217, 239 and 253 Tg, of which 45, 60 and 63 Tg of dry biomass are estimated to be subjected to FBCR in the years 1994, 2005 and 2010, respectively. Wheat and rice crops together accounted for about 76% of this. Burning of such huge amount of biomass is estimated to emit 22.4, 24.4 and 26.1 Tg of carbon; 0.30, 0.33 and 0.35 Tg of nitrogen; 4.18, 4.59 and 4.86 Tg carbon dioxide equivalent of greenhouse gases (GHG, viz., CH4 and N2O; which is over 1% of the Indian agriculture sector GHG emissions); 2951, 3,240 and 3,431 Gg of CO; and 120.8, 132.9 and 140.6 Gg NOx emissions in 1994, 2005 and 2010, respectively. Further, the Indian states of U.P, Punjab, Haryana, M.P, Maharashtra, T.N, Karnataka, Andhra Pradesh, Bihar and W.B have been found to contribute maximum to the Indian FBCR emissions. FBCR avoidance and optimum utilization of crop-residue resource is urgently required for agro-ecosystem sustainability in the region.

Chemical speciation, transport and contribution of biomass burning smoke to ambient aerosol in Guangzhou, a mega city of China

Intensive measurements of aerosol (PM 10) and associated water-soluble ionic and carbonaceous species were conducted in Guangzhou, a mega city of China, during summer 2006. Elevated levels of most chemical species were observed especially at nighttime during two episodes, characterized by dramatic build-up of the biomass burning tracers levoglucosan and non-sea-salt potassium, when the prevailing wind direction had changed due to two approaching tropical cyclones. High-resolution air mass back trajectories based on the MM5 model revealed that air masses with high concentrations of levoglucosan (43–473 ng m −3) and non-sea-salt potassium (0.83–3.2 μg m −3) had passed over rural regions of the Pearl River Delta and Guangdong Province, where agricultural activities and field burning of crop residues are common practices. The relative contributions of biomass burning smoke to organic carbon in PM 10 were estimated from levoglucosan data to be on average 7.0 and 14% at daytime and nighttime, respectively, with maxima of 9.7 and 32% during the episodic transport events, indicating that biomass and biofuel burning activities in the rural parts of the Pearl River Delta and neighboring regions could have a significant impact on ambient urban aerosol levels.