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Synergistic use of very high-frequency radar and discrete-return lidar for estimating biomass in temperate hardwood and mixed forests 总被引:1,自引:0,他引:1
Asim Banskota Randolph H. Wynne Patrick Johnson Bomono Emessiene 《Annals of Forest Science》2011,68(2):347-356
• Introduction
Accurate estimation of aboveground biomass is essential to better understand the carbon cycle in forest ecosystems. 相似文献4.
A linear programming (LP) based optimization model and a simulation model are developed and applied in a typical diversion type irrigation system for land and water allocation during the dry season. Optimum cropping patterns for different management strategies are obtained by the LP model for different irrigation efficiencies and water availability scenarios. The simulation model yields the risk-related irrigation system performance measures (i.e. reliability, resiliency and vulnerability) for the management policies defined by the optimization model. The alternative strategies are evaluated in terms of all performance criteria (i.e. net economic benefit, equity and reliability) simultaneously through a trade-off analysis using a multi-criteria decision making method (compromise programming). For the case study of the Kankai irrigation system in Nepal, with equal preference to the objectives, a management strategy with equal share of water among the project subareas appears to be the most satisfactory alternative under water shortage conditions. The existing water allocation policy is not economically efficient. Deficit irrigation in Early paddy appears attractive under favorable hydrologic scenario, particularly if accompanied by measures to improve existing irrigation system efficiency. 相似文献
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Changes in the specific activities of polyphenol oxidase (PPO), peroxidase (POD), and protease and in the relative amounts of flavan-3-ols for eight genetically derived cultivated teas at various stages of leaf maturity and in four succescive seasons were examined. A series of investigations were carried out to study the cross-reactivity of complex polyphenols and PPO-generated orange-yellow theaflavins, as well as of POD oxidized substrates, producing brown so-called thearubigins during fermented tea processing. From the estimation of five major catechins, PPO activities in young shoots, and theaflavin and thearubigin contents of crushed, torn, and curled (CTC) black teas, the superior variety and flavorful flush characteristics were refined. Notable protein hydrolysis by endogenous protease as measured from free amino acids and formation of tannin-protein complex (browning products) was obtained for cultivar character and product quality. Results showed that process optimization with respect to time, temperature, moisture, and pH maximizes PPO-catalyzed desirable theaflavin pigments, whereas POD-mediated chemical reaction produces dull color. 相似文献
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Asit Mandal Jyoti Kumar Thakur Asha Sahu Madhab Chandra Manna Annangi Subba Rao Binoy Sarkar 《Archives of Agronomy and Soil Science》2019,65(5):670-685
Growing areas under transgenic crops have created a concern over their possible adverse impact on the soil ecosystem. This study evaluated the effect of Bt-cotton based cropping systems on soil microbial and biochemical activities and their functional relationships with active soil carbon pools in Vertisols of central India (Nagpur, Maharastra, during 2012–2013). Culturable groups of soil microflora, enzymatic activities and active pools of soil carbon were measured under different Bt-cotton based cropping systems (e.g. cotton-soybean, cotton-redgram, cotton-wheat, cotton-vegetables and cotton-fallow). Significantly higher counts of soil heterotrophs (5.7–7.9 log cfu g?1 soil), aerobic N-fixer (3.9–5.4 log cfu g?1 soil) and P-solubilizer (2.5?3.0 log cfu g?1 soil) were recorded in Bt-cotton soils. Similarly, soil enzymatic activities, viz. dehydrogenase (16.6–22.67 µg TPF g?1 h?1), alkaline phosphatase (240–253 µg PNP g?1 h?1) and fluorescein di-acetate hydrolysis (14.6–18.0 µg fluorescein g?1 h?1), were significantly higher under Bt-cotton-soybean system than other Bt- and non-Bt-cotton based systems in all crop growth stages. The growth stage-wise order of soil microbiological activities were: boll development > harvest > vegetative stage. Significant correlations were observed between microbiological activities and active carbon pools in the rhizosphere soil. The findings indicated no adverse effect of Bt-cotton on soil biological properties. 相似文献
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Jinghua Liu Arjun H. Banskota Alan T. Critchley Jeff Hafting Balakrishnan Prithiviraj 《Marine drugs》2015,13(4):2250-2266
Parkinson’s disease (PD) is the second most common neurodegenerative disorder in the elderly people, currently with no cure. Its mechanisms are not well understood, thus studies targeting cause-directed therapy or prevention are needed. This study uses the transgenic Caenorhabditis elegans PD model. We demonstrated that dietary supplementation of the worms with an extract from the cultivated red seaweed Chondrus crispus decreased the accumulation of α-synulein and protected the worms from the neuronal toxin-, 6-OHDA, induced dopaminergic neurodegeneration. These effects were associated with a corrected slowness of movement. We also showed that the enhancement of oxidative stress tolerance and an up-regulation of the stress response genes, sod-3 and skn-1, may have served as the molecular mechanism for the C. crispus-extract-mediated protection against PD pathology. Altogether, apart from its potential as a functional food, the tested red seaweed, C. crispus, might find promising pharmaceutical applications for the development of potential novel anti-neurodegenerative drugs for humans. 相似文献
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