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31.
S. Aulong B. Chaudhuri L. Farnier S. Galab J. Guerrin H. Himanshu P. Prudhvikar Reddy 《Regional Environmental Change》2012,12(3):423-436
Global changes are already having an impact on South Indian farmers. Climate change is affecting the agricultural sector since it is dependent on climatic conditions and water resource availability. The impacts tend to be greater in semi-arid hard rock areas with few water resources. Furthermore, South India area is experiencing a profound agrarian crisis, which is linked, among others, to debt and credit problems. The study reported in this paper aims to develop a methodology to compare and rank farmers according to their ability to adapt to global change. The definition of adaptive capacity is based on a livelihood assets approach. Indicators are evaluated through individual surveys among farmers, then, weighted using the analytic hierarchy process and aggregated via compromise programming. The result is a standardized score measuring the distance of each farmer from an ideal adaptive capacity. Farmers are ranked according to this distance, which allows a comparison of their relative ability to adapt. At the basin scale, it shows that the geographic position of farmers is a significant factor in adaptation performance. The proximity of an administrative center contributes to an increase of their adaptive capacity. Small farming areas limit the adaptive capacities of marginal and small farmers while the largest farmers are constrained by economic factors such as large loans. These study findings offer interesting indications on the variability of farmers’ weaknesses and are bringing a better understanding of the causes of poor performance. 相似文献
32.
Faibil Daniel Agyemang Martin Amponsah Owusu Gupta Himanshu Kusi-Sarpong Simonov 《Environment, Development and Sustainability》2021,23(11):15785-15829
Environment, Development and Sustainability - Many stakeholders in agro-food industry are concerned about sustainability, especially in addressing post-harvest loss (PHL). However, resources... 相似文献
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34.
Bhatia A Pathak H Jain N Singh PK Tomer R 《Environmental monitoring and assessment》2012,184(5):3095-3107
Conventional blanket application of nitrogen (N) fertilizer results in more loss of N from soil system and emission of nitrous
oxide, a greenhouse gas (GHG). The leaf color chart (LCC) can be used for real-time N management and synchronizing N application
with crop demand to reduce GHG emission. A 1-year study was carried out to evaluate the impact of conventional and LCC-based
urea application on emission of nitrous oxide, methane, and carbon dioxide in a rice–wheat system of the Indo-Gangetic Plains
of India. Treatments consisted of LCC scores of ≤4 and 5 for rice and wheat and were compared with conventional fixed-time
N splitting schedule. The LCC-based urea application reduced nitrous oxide emission in rice and wheat. Application of 120 kg
N per hectare at LCC ≤ 4 decreased nitrous oxide emission by 16% and methane by 11% over the conventional split application
of urea in rice. However, application of N at LCC ≤ 5 increased nitrous oxide emission by 11% over the LCC ≤ 4 treatment in
rice. Wheat reduction of nitrous oxide at LCC ≤ 4 was 18% as compared to the conventional method. Application of LCC-based
N did not affect carbon dioxide emission from soil in rice and wheat. The global warming potential (GWP) were 12,395 and 13,692 kg CO2 ha−1 in LCC ≤ 4 and conventional urea application, respectively. Total carbon fixed in conventional urea application in rice–wheat
system was 4.89 Mg C ha−1 and it increased to 5.54 Mg C ha−1 in LCC-based urea application (LCC ≤ 4). The study showed that LCC-based urea application can reduce GWP of a rice–wheat
system by 10.5%. 相似文献
35.
Ernesto Di Maio Raed Mali Salvatore Iannace 《Journal of Polymers and the Environment》2010,18(4):626-633
Conventional direct melt mixing technology was investigated on zein and kafirin, two vegetable proteins extracted, respectively,
from maize and sorghum. A lab scale internal mixer has been used to thoroughly study the thermo-plasticization process of
the proteins with several plasticizers. Different compositions were investigated under different processing conditions. In
particular, the lengthy procedures of forming the protein/solvent/plasticizer solution followed by drying or the protein/plasticizer
emulsion followed by the precipitation of the extrudable resin, reported in the literature for these systems, were avoided
and the protein and plasticizer were directly fed into the mixer to obtain a plastic-like material. The effect of plasticizer
type and content and mixing process variables on the mechanical properties was analyzed. Compression molded slabs were transparent,
strong and flexible, with properties similar to the cast films reported in the literature, prepared with the same type of
plasticizers. However, lower plasticizer content was sufficient to produce equally flexible films, proving an enhanced plasticization
efficiency of the mixing process, as compared to casting. 相似文献
36.
Cristina P. B. Melo Maria V. E. Grossmann Fábio Yamashita Elza Y. Youssef Luiz Henrique Dall’Antônia Suzana Mali 《Journal of Polymers and the Environment》2011,19(3):739-749
The objective of this work was to manufacture biodegradable films by two different processes (casting and extrusion), from
different combinations of cassava starch and xanthan gum. These films were produced by casting and by extrusion from six different
starch-xanthan gum combinations (0, 2, 4, 6, 8 and 10% w/w), containing glycerol as plasticizer (20% w/w) and were also characterized
according to their microstructure, optical, mechanical, and barrier properties. Scanning electron microscopy of the starch-xanthan
gum extruded films showed reticulated surface and smooth interior, suggesting that xanthan was driven to the surface and gelatinized
starch to the interior of the films during extrusion. Films manufactured by casting were entirely homogeneous. In general,
casted films presented lower opacity and water vapor permeability and higher stress at break than films manufactured by extrusion.
Xanthan gum addition affected mechanical properties of starch films, improving their stress and strain at break, especially
for extruded samples, but these properties did not show stability at different RH conditions. 相似文献
37.
Ngamlerdpokin K Kumjadpai S Chatanon P Tungmanee U Chuenchuanchom S Jaruwat P Lertsathitphongs P Hunsom M 《Journal of environmental management》2011,92(10):2454-2460
The remediation of biodiesel wastewater was carried out using chemical and electrochemical techniques. Initially the fatty acid methyl esters (FAME or biodiesel) and free fatty acids (FFA) were chemically removed from the wastewater using three types of mineral acids, H(2)SO(4), HNO(3) and HCl, at different pH values within the range of 1.0-8.0. Optimally, approximately 24.3 ml/l of FAME/FFA were removed from the wastewater when using H(2)SO(4) to set a final pH of 2.5 for 7 min. All pollutant levels were markedly reduced during this step. That is, approximately 38.94%, 76.32% and 99.36% of COD, BOD5 and oil & grease were respectively removed. The acidic aqueous phase left after the removal of the FAME/FFA phase was then treated by chemical- and electro-coagulation processes. The results demonstrated that both investigated treatment processes were effective for treating wastewater from a biodiesel production plant. The chemical coagulation provided a lower operating cost (1.11 USD/m(3)) compared with the electro-coagulation process (1.78 USD/m(3)). However, the latter process provided a better quality of wastewater compared with the former process, with the exception of the BOD levels. 相似文献
38.
Himanshu Joshi S. K. Shishodia S. N. Kumar D. K. Saikia B. P. Nauriyal R. P. Mathur P. K. Pande B. S. Mathur N. Puri 《Environmental monitoring and assessment》1995,35(3):181-206
A multi-disciplinary research programme on the Ganga River Ecosystem was launched by the Government of India in 1983 to collect information on its attributes. Monitoring of the initial 509 km unpolluted and unmonitored region of the river falling in partly mountainous and partly upper plain stretches for two years revealed good water quality. The Song River (a tributary) catchment, a victim of extensive mining activity in the past, was found to add maximum mineral load. The Bhagirathi River was found to carry maximum suspended solid load. Organic pollution was low throughout, occasionally showing seasonal and local peaks. The river exhibited a high oxidative state with pH falling in a slightly alkaline range and nutrient levels being very low.Diatoms formed a major part of the encountered genera of phytoplankton. Zooplankton were mainly represented by protozoans. Saprophytic bacteria underwent large spatial and temporal fluctuations. Coliforms exhibited an increasing trend with downstream river distance. The source of pollution could not be specifically characterized from an FC/FS ratio. Only one sample tested positive for enteric virus. The forms of benthic macroinvertebrates indicated a clean stream environment. It was observed that diversity indices, together with evenness and community comparison, could provide a promising approach to determine the state of the community.Eight heavy metals investigated, Cu, Zn, Fe, Cd, Mn, Pb, Ni and Co, were found to be present in the river water and bed sediments. The prominent mode of metal transport was found to be via the suspended load. The concentration of dissolved metals was found within WHO permissible limits. The heavy metal status of the Ganga River was compared with other rivers of the world. Sorptive properties of sediments were found to be similar to the general sorptive behaviour of the clays. Laboratory studies exhibited reasonable short t
90 values for coliform survival in Ganga water. Faecal streptococcus survived longer. 相似文献
39.
Krishnani Kishore Kumar Boddu Veera Mallu Chadha Narinder Kumar Chakraborty Puja Kumar Jitendra Krishna Gopal Pathak Himanshu 《Environmental science and pollution research international》2022,29(54):81130-81165
Environmental Science and Pollution Research - Global agriculture is facing tremendous challenges due to climate change. The most predominant amongst these challenges are abiotic and biotic... 相似文献
40.
为比较在不同宿主中表达的大肠杆菌植酸酶突变体app AM8的性质,将app AM8基因分别在大肠杆菌BL21(DE3)和毕赤酵母GS115中进行表达,对纯化后的植酸酶进行酶学性质分析与比较.结果显示:(1)在大肠杆菌中表达的app AM8(E-app AM8)和酵母中表达的app AM8(P-app AM8)的最适p H值均为4.5,最适反应温度均为65℃,与野生型的app A的最适p H无明显区别,比app A的最适温度高了5℃;(2)经SDS-PAGE检测,E-app AM8分子量(Mr)大小为47×103,而P-app AM8为53×103左右,由于在酵母中的糖基化修饰电泳显示为两条带;(3)在60-80℃之间,E-app AM8的热稳定性性明显下降,而且在70℃处理15 min后,E-app AM8残余活性仅为4%,而P-app AM8仍保留50%的残余活性,表明酵母表达的植酸酶经过糖基化修饰后提高了酶的热稳定性.(4)E-app AM8的Km=0.245 mmol/L,Vmax=3196 U/mg,P-app AM8的Km=0.36 mmol/L,Vmax=3333 U/mg.本研究表明,糖基化修饰对植酸酶app AM8的热稳定性起着重要作用,8个位点的突变对该植酸酶的稳定性也起到了一定作用. 相似文献