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921.
Resource conservation strategies for rice‐wheat cropping systems on partially reclaimed sodic soils of the Indo‐Gangetic region,and their effects on soil carbon 下载免费PDF全文
V.K. Mishra S. Srivastava A.K. Bhardwaj D.K. Sharma Y.P. Singh A.K. Nayak 《Natural resources forum》2015,39(2):110-122
The Indo‐Gangetic plain is characterized by intensive agriculture, largely by resource‐poor small and marginal farmers. Vast swathes of salt‐affected areas in the region provide both challenges and opportunities to bolster food security and sequester carbon after reclamation. Sustainable management of reclaimed soils via resource conservation strategies, such as residue retention, is key to the prosperity of the farmer, as well as increases the efficiency of expensive initiatives to further reclaim sodic land areas, which currently lay barren. After five years of experimentation on resource conservation strategies for rice‐wheat systems on partially reclaimed sodic soils of the Indo‐Gangetic region, we evaluated changes in different soil carbon pools and crop yield. Out of all resource conservation techniques which were tested, rice‐wheat crop residue addition (30% of total production) was most effective in increasing soil organic carbon (SOC). In rice, without crop residue addition (WCR), soils under zero‐tillage with transplanting, summer ploughing with transplanting and direct seeding with brown manuring showed a significant increase in SOC over the control (puddling in rice, conventional tillage in wheat). In these treatments relatively higher levels of carbon were attained in all aggregate fractions compared to the control. Soil aggregate sizes in meso (0.25‐2.0 mm) and macro (2‐8 mm) ranges increased, whereas micro (< 0.25 mm) fractions decreased in soils under zero‐till practices, both with and without crop residue addition. Direct seeding with brown manuring and zero tillage with transplanting also showed an increase of 135% and 95%, respectively, over the control in microbial biomass carbon, without crop residue incorporation. In zero tillage with transplanting treatment, both with and without crop residue showed significant increase in soil carbon sequestration potential. Though the changes in accrued soil carbon did not bring about significant differences in terms of grain yield, overall synthesis in terms of balance between yield and carbon sequestration indicated that summer ploughing with transplanting and zero tillage with transplanting sequestered significantly higher rates of carbon, yet yielded on par with conventional practices. These could be appropriate alternatives to immediately replace conventional tillage and planting practices for rice‐wheat cropping systems in the sodic soils of the Indo‐Gangetic region. 相似文献
922.
Amesho Kassian T. T. Lin Yuan-Chung Mohan S. Venkata Halder Subham Ponnusamy Vinoth Kumar Jhang Syu-Ruei 《Environmental Chemistry Letters》2023,21(1):183-230
Environmental Chemistry Letters - The global energy demand has been projected to rise over 28% by 2040, calling for more renewable resources such as lignocellulosic biomass to produce biofuels, and... 相似文献
923.
Rajendran Devi Sri Chidambaram Ashok Kumar Ponnusamy Senthil Venkataraman Swethaa Muthusamy Shanmugaprakash Vo Dai-Viet Nguyen Rangasamy Gayathri Vaithyanathan Vasanth Kumar Vaidyanathan Vinoth Kumar 《Environmental Chemistry Letters》2023,21(2):911-934
Environmental Chemistry Letters - Modern biomass and organic waste are becoming major, carbon-neutral sources of fine chemicals, biomolecules and fuels to replace fossil fuel products. As a... 相似文献
924.
Gautam Aparna Khajone Vijay B. Bhagat Pundlik R. Kumar Sushil Patle Dipesh S. 《Environmental Chemistry Letters》2023,21(6):3105-3126
Environmental Chemistry Letters - Diminishing petroleum reserves, increasing carbon emissions, and the growing demand for fuels are calling for alternative fuels. Global diesel consumption... 相似文献
925.
Shrivastava JN Satsangi GP Kumar A 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(1):125-126
Prevalence of keratinophilic fungi was observed in paddy field soil during different stages of cultivation viz., transplanting, tillering, milking and maturation. Out of total 76 soil samples, 65 soil samples were found to be positive for the keratinophilic fungi. Fourteen species belonging to a single genus Chrysosporium were isolated through out the cropping season. C. keratinophilum (17.1%) followed by C. tropicum (13.15%) were found to be the most dominating geophilic species. The highest percent distribution of keratinophilic fungi appeared during the milking stage (100%) of paddy cultivation, followed by the maturation stage (89.47%). 相似文献
926.
Banu JR Yeom IT Esakkiraj S Kumar N Logakanthi S 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(2):143-146
Sago, the tapioca starch is manufactured by over 800 small-scale units located in the Salem district, Tamil Nadu, India. During the processing of sago it generates huge quantities of biodegradable solid waste, as crushed tubers. In present study an attempt was made to convert these biodegradable solid sago tubers into value added compost using an exotic earthworm, Eudrilus eugeniae. The experiments were carried out in a plastic tray at various concentrations of sago-sludge (50% 75% and 100%) for a period of 90 days. During the vermicomposting, data were collected on life form (cocoon, non clitellates, clitellates) of earthworm and it was found to be high in 50% followed by 75% and 100% concentrations. Chemical analysis of worked substrates showed a step wise increase of nitrogen and phosphorus. The fold increase of phosphorus and nitrogen were found to be high for sago-sludge undergoing vermicomposting than the control. During the composting period the organic carbon decreased from its initial value of 58, 76 and 107 mg/kg to 21, 24 and 65 mg/kg for 50, 70 and 100%, respectively The microbial analysis showed that after 75 days of composting, their population stabilized and further increase in composting period did not increase their population size. The results indicate that 50% and 75% concentration of sludge mixed with bedding material was ideal for the vermicomposting. 相似文献
927.
People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of
which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which
is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers
on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement
of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly
selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer
is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state
nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those
fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results
were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers. 相似文献
928.
Mansuri Abdulkhalik Chaudhari Ramesh Nasra Simran Meghani Nikita Ranjan Shivendu Kumar Ashutosh 《Environmental science and pollution research international》2023,30(10):24907-24918
Environmental Science and Pollution Research - Antimicrobials of natural origin are proving to be an effective solution to emerging antimicrobial resistance and its physiological side effects.... 相似文献
929.
Kumar Anuj Ingle Anjali Shende Diwakar Z. Wasewar Kailas L. 《Environmental science and pollution research international》2023,30(10):24890-24898
Environmental Science and Pollution Research - Levulinic acid is a carboxylic acid present in industrial downstream. It is an important chemical and can be transformed into various important... 相似文献
930.
Kumar Sarangi Prakash Subudhi Sanjukta Bhatia Latika Saha Koel Mudgil Divya Prasad Shadangi Krushna Srivastava Rajesh K. Pattnaik Bhabjit Arya Raj Kumar 《Environmental science and pollution research international》2023,30(4):8526-8539
Environmental Science and Pollution Research - The major global concern on energy is focused on conventional fossil resources. The burning of fossil fuels is an origin of greenhouse gas emissions... 相似文献