Md. Khairul Alam | Murdoch University (original) (raw)

Papers by Md. Khairul Alam

Field Crops Research, May 1, 2020

On-farm adoption of minimum soil disturbance and increased residue retention will alter nitrogen ... more On-farm adoption of minimum soil disturbance and increased residue retention will alter nitrogen (N) dynamics in soils and N fertiliser management in the intensive rice-based triple cropping systems of the Eastern Gangetic Plains. However, the consequences of changes in N forms, N mineralisation and its availability for crops have not been determined. Field experiments were conducted at two locations (Alipur and Digram) of northwest Bangladesh (NWB) to examine N cycling under three planting practices (conventional tillage (CT), strip planting (SP) and bed planting (BP)) with increased (HR) or low residue retention (LR-the current practice) on Calcareous Brown Flood Plain and Grey Terrace soils. Total N and available N were measured on soil samples as was N uptake by crops at different growth stages in the 13-14th (Alipur) and 12-13th (Digram) crops since treatments commenced. At each location (0-10 cm soil depth), SP, including non-puddled transplanting of rice seedlings (NP), together with HR increased total N by 9 and 32 % relative to BPHR, and CTHR and by 62 % relative to the current farm practice (CTLR). In general, the cumulative available N in soils during mustard and rice cropping under CT with HR was higher than other crop establishment and residue retention practices while under wheat and jute, total availability of N did not vary among crop establishment types with increased residue retention. Nitrogen availability in the initial phase of crop growth (0-60 DAS) was generally higher with CT than SP and BP. By contrast, for all crops, the estimated potentially mineralisable N was higher and its decay rate was lower under SPHR than other crop establishment and residue retention practices. Conservation Agriculture practices (SP, and NP of rice, together with HR) have altered the N cycling by reducing the level of mineral N available to plants in the early growing season when crop demand is low, but by increasing soil total N (0−10 cm) and plant N uptake which enhanced the synchrony between crop demand and available N supply. establishment practice designed for CA cropping systems (Alam et al., 2016a; Haque et al., 2016), along with zero tillage or strip planting are CA-compatible practices for rice. However, there is limited understanding of cycling of N in soils under the CA practices in intensive rice-based triple cropping systems which involve the rotation of winter dryland and summer wetland rice crops. An improved knowledge about the dynamics of residue nitrogen (N) turnover and the availability of both soil native N and fertiliser N is required to quantify the effects of minimum soil disturbance and increased crop residue retention on soil quality, crop production and N fertilizer management. As native soil N mineralisation provides 20-80

Journal of Cleaner Production, Jul 1, 2019

Wetland rainfed rice (Oryza sativa L.), which covers 60 million hectares in South Asia, contribut... more Wetland rainfed rice (Oryza sativa L.), which covers 60 million hectares in South Asia, contributes significantly to agricultural greenhouse gas (GHG) emissions. Mitigation strategies for GHG emissions by wetland rice production are of considerable importance. Life cycle assessment of GHG emissions can be used to assess the mitigation potential of new rice production practices such as seedling establishment on non-puddled soil. The aim of the study was firstly to determine the GHG mitigation potential of rain-fed rice production by changing to non-puddled transplanting and increased crop residue retention and secondly to determine the addition contribution of soil carbon sequestration to net GHG emissions with the altered crop establishment approach. A cradle to farm-gate Life Cycle Analysis was used to calculate GHG emissions associated with monsoon rice production in rice-based intensive cropping systems of Northwest Bangladesh. The non-puddled transplanting and low residue retention decreased the net life cycle assessment GHG emissions (CO 2 eq) by 31 % in comparison with the current puddled transplanting and increased crop residue retention. By contrast, non-puddling with increased residue retention reduced emission of the net GHG by 16 % in comparison with current puddling and low residue retention. Regardless of rice establishment practices, CH 4 was the most prevalent GHG emission comprising 63 to 67 % of the total GHGs, followed by 17-20 % from CO 2 emissions from the field. The GHG emissions tonne-1 rice after accounting for soil carbon storage ranged from 1.04 to 1.18 tonne CO 2 eq for non-puddling with low and increased crop residue retention, respectively. The inclusion of soil carbon in the footprint equation represents a 26 % reduction of estimated GHG emissions under non-puddled soil with increased residue retention. Overall, non-ACCEPTED MANUSCRIPT puddled transplanting with increased crop residue retention was an effective GHG mitigation option in wetland monsoon rice production because the increased yield and extra soil organic carbon storage more than offset its higher CH 4 emissions than with low residue retention.

Soil & Tillage Research, Nov 1, 2018

The adoption of conservation agriculture (CA) in the intensive triple-cropping, rice-based system... more The adoption of conservation agriculture (CA) in the intensive triple-cropping, rice-based systems of the Eastern Gangetic Plain (EGP) alters the dynamics of carbon (C) in the soil, but the nature of these changes is poorly understood. Our aim was to determine whether CA in these systems involving non-puddled transplanting of wetland rice and strip planting of dryland crops plus increased residue retention would increase the C storage in soils relative to conventional crop establishment practices. Long-term field experiments were studied in two locations of northwestern Bangladesh to determine C turnover as well as examining C cycling under three levels of soil disturbance (conventional tillage (CT), strip planting (SP) and bed planting (BP)) in combination with low residue (straw) retention (LR, the current practice) and increased residue retention (HR) in Calcareous Brown Floodplain soil (Alipur) and Grey Terrace soil (Digram). The total nitrogen (N), organic C, microbial biomass C (MBC) and water-soluble C (WSC) values were measured in soil samples from 0 to 10 cm depth collected at different stages during the growth of the 13th and 14th crops at Alipur and the 12th and 13th crops at Digram since the treatments commenced. At each location, SP and BP with either LR or HR retained more soil organic C (0-10 cm) from C inputs than CT with HR and LR. In general, the CO 2 emissions relative to the stored soil organic C in the soils (0-10 cm) under SP with LR and HR were approximately 13 to 59% lower than those under CT and BP with LR and HR. The higher levels of C mineralization were associated with higher WSC contents in the soil. In contrast, the MBC contents in the HR treatments followed the order SPHR > BPHR > CTHR. Similarly, in SPLR and SPHR, the potentially mineralizable C (PMC) was higher, while the decay rate constant was lower. Increased residue retention with minimal soil disturbance practices (SP and non-puddled transplanting) after 14 crops at Alipur and 13 crops at Digram modified the C cycle by decreasing C emissions and increasing the levels of total organic C in the soil. The application of both minimal soil disturbance and increased residue retention enhanced soil organic C (0-10 cm) concentrations in the two soils under intensive rice-based cropping systems on the EGP.

Long-term impact of smallholders’ conservation agriculture in rainfed and irrigated systems

No abstract availabl

Journal of Cleaner Production, May 1, 2019

Emerging conservation agriculture (CA) technologies are being applied in rice-upland cropping sys... more Emerging conservation agriculture (CA) technologies are being applied in rice-upland cropping systems and their potential to mitigate greenhouse gas emissions of the whole ricebased cropping systems could be significant in South Asia especially if they increase soil organic carbon (SOC) stocks. A streamlined life cycle assessment was conducted in the Eastern Gangetic Plains (Bangladesh) to determine greenhouse gas emissions from successive crops of monsoon rice (Oryza sativa), mustard (Brassica juncea) and irrigated rice under CA practices in contrast with the conventional crop establishment practice while accounting for changes in SOC. The life cycle greenhouse gas tonne-1 rice equivalent yield was assessed for four cropping practices: a) traditional crop establishment practices with farmers' practice of minimal residue return, or b) CT with return of increased residues; c) strip planting (for mustard)/ transplanting on non-puddled soils (for rice) with farmers' practice of minimal residue return or; d) strip planting/non-puddled transplanting with increased residue return. The global warming potential values for the 100-year timescale were used to calculate CO 2 eq emissions within the system boundary. The net life cycle greenhouse gas emissions after allowing for changes in SOC sequestration varied from 0.73 to 1.12 tonne CO 2 eq tonne-1 rice equivalent yield. In the annual cropping system, methane (CH 4) released from on-farm stage of the life cycle assessment, particularly from the rice crops, represented the dominant contributor to life cycle greenhouse gas emissions. The greenhouse gas emitted by machinery usage during the on-farm stage (irrigated rice), CO 2 emission from soil respiration (monsoon rice), and greenhouse gas related to manufacture of inputs (mustard) were secondary sources of emission, in that order of priority. The non

Annals of Bangladesh agriculture, Dec 4, 2022

Growth and breedinG performance of broodfish and larval Growth of Heteropneustes fossilis with fe... more Growth and breedinG performance of broodfish and larval Growth of Heteropneustes fossilis with feeds a. c. sinha 1 , m. a. salam 1 , s. K. mazumder 1 , m. s. alam 1 and m. l. rahman 1 * abstract A 63-day long indoor experiment was carried out to determine the effects of four different diets of: live tubificid worms (T 1), live tubificid worms with formulated feed (T 2), shrimp with formulated feed (T 3) and formulated feed (T 4) on brood development and larval growth of Heteropneustes fossilis. Broodfish were fed twice a day with experimental diets. Reproductive performance of H. fossilis was evaluated based on growth parameters and fry production of broodstock. The result showed that while the highest (16.37 ± 0.90g) and the lowest (7.03 ± 0.85g) weight gain was obtained in T 2 and T 4 respectively, however, there was no significant difference between treatments T 1 and T 3. The FCR of T 2 was found to be the lowest followed by T 3 , T 1 and T 4 , respectively. The highest fecundity was found in T 2 (4245.48 ± 347.38) followed by T 3 (3747.10 ± 317.99), T 1 (3583.96 ± 327.27) and T 4 (3191.95 ± 444.55). The rate of hatching and their survival was significantly higher in T 2 followed by T 3 , whereas T 1 and T 4 showed significantly lower hatching and survival rate. After 28 days of rearing, larvae obtained from T 2 treatment showed the highest growth performance compared to other treatments. The findings of the current research suggested that live feed (tubificid worms) supplemented with formulated feed may enhance the breeding performance and larval growth of H. fossilis and could be considered an affordable option for small-scale hatcheries.

Bangladesh Journal of Agricultural Research, Sep 25, 2018

An experiment was conducted at the Agronomy Field of Patuakhali Science and Technology University... more An experiment was conducted at the Agronomy Field of Patuakhali Science and Technology University, Dumki, Patuakhali from June to December, 2013 to find out the effect of variety and planting density on the yield and yield attributing characters of local aromatic rice. The experiment was laid out in a factorial randomized complete block design with three replications, which consisted of three local aromatic rice varieties (Chinigura, Shakhorkhora and Kalizira) and four planting densities were viz. S1 (25 cm × 20 cm), S2 (20 cm × 20 cm), S3 (20 cm × 15 cm) and S4 (20 cm × 10 cm). The results revealed that the local aromatic rice var. Shakhorkhora variety produced the highest number of grains per panicle (131) and 1000-grain weight (13.8 g), consequently higher grain (2.63 t ha-1), followed by Kalizira (2.56 t ha-1) and straw yield (4.21 t ha-1). One the other hand, higher number of tillers per hill (14.8), number of grains per panicle (140 nos.) were found in 20 cm × 20 cm spacing with higher grain yield.

Cropping Pattern-Based Fertilizer Strategies For Crop Productivity and Soil Health Under Minimum Tillage in Grey Terrace Soil

Agronomy

In intensive crop production systems, sustainable agricultural development strives to find the ba... more In intensive crop production systems, sustainable agricultural development strives to find the balance between productivity and environmental impact. To reduce the N fertilizer-associated environmental risks of intensive cropping, sound agronomic and environmentally acceptable management practices are urgently needed. To attain high yields, improve soil health, and ensure economic return and N usage efficiency in conservation-based intensive agriculture, N management must be optimized, which has not yet been studied systematically in the mustard-boro rice-aman rice cropping pattern. During 2016/17, 2017/18, and 2018/19 cropping seasons in Bangladesh, cropping system experiments were conducted to investigate the interactive effects of tillage practices and nitrogen fertilizer rates on soil characteristics, crop productivity, and profitability under conservation agriculture (CA) systems. The trial featured two tillage systems: (i) conventional tillage (CT) and (ii) strip-tillage (ST)....

Tillage systems influence on greenhouse gas emission factor and global warming potential under rice-mustard-rice cropping system

Archives of Agronomy and Soil Science, 2022

Indian Journal Of Agricultural Research, 2021

Background: Scarcity of improved cultivars with wide adaptability and stability in tuber yield is... more Background: Scarcity of improved cultivars with wide adaptability and stability in tuber yield is one of the most important reasons for poor yield of potato in Bangladesh. The stable cultivars which perform well over a wide range of environments become very important for farmers and processors because they require reliable production and quality. The current study was aimed to evaluate 10 potato genotypes (eight BARI released cultivars and two advanced clones) grown in six regions to find high yielding and stable performing genotypes. Methods: Ten potato genotypes were evaluated at six locations of Bangladesh during season 2017-2018 following a randomized complete block design with three replications. The potato genotypes were sown on 15th November 2017. Fertilizer doses, irrigation, plant protection, weeding, earthing up and other agronomic practices were applied according to Tuber Crops Research Center (TCRC), Bangladesh Agricultural Research Institute (BARI) recommendation. Plant...

Conservation Agriculture Improves Soil Health: Major Research Findings from Bangladesh

Conservation Agriculture: A Sustainable Approach for Soil Health and Food Security, 2021

Wetland rice (Oryza sativa L.) production contributes 55% of agricultural greenhouse gas emission... more Wetland rice (Oryza sativa L.) production contributes 55% of agricultural greenhouse gas emissions globally. Any new technology with the potential to reduce the greenhouse gas emissions from wetland rice could therefore make a significant contribution to total global warming mitigation by agriculture.

Combined use of chemical insecticides and potash fertilizer on growth, juice quality and yield of sugarcane in Bangladesh

Indian sugar, 2009

Actions of Biological Trace Elements in Plant Abiotic Stress Tolerance

Springer eBooks, 2017

With the increase of global population, the demand for food crops, oil, fiber and other by-produc... more With the increase of global population, the demand for food crops, oil, fiber and other by-product yielding crops is increasing. In contrast to this increasing demand, abiotic stresses hinder the productivity of plants. Abiotic stresses sometimes reduce more than half of the crop yields. To attain global food security, understanding of plant responses to abiotic stresses is crucial because this is the prerequisite for developing approaches/tools for improving plant stress tolerance. Trace elements are nutrients required in small quantities to facilitate a range of physiological functions. These elements stimulate growth but are not essential. Some are essential only for certain plant species or required under a given condition. Trace elements not only improve plant physiological processes and growth but play roles in improving plant stress tolerance. However, the actual physiological functions of trace elements in conferring abiotic stress tolerance are still under study. This chapter focuses on the roles of trace elements emphasizing especially the recent advances on the actions of biological trace elements in plant abiotic stress tolerance.

An analytical approach to real-time cloud services on IoT-based applications for smart city planning

International Journal of Grid and Utility Computing, 2021