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中低产田管灌工程改造技术
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作者 陆恒 《福建农业》 1998年第2期10-11,共2页
福安地处我省东北部,是个人多地少、工业欠发达的农业市。人均耕地0.58亩,低于全国人均耕地临界值0.8亩。长期以来,我市十分珍惜耕地,重视中低产田改造,挖掘耕地潜力。80年代第二次土壤普查后,我们侧重于生物技术对中低产田改造,取得了... 福安地处我省东北部,是个人多地少、工业欠发达的农业市。人均耕地0.58亩,低于全国人均耕地临界值0.8亩。长期以来,我市十分珍惜耕地,重视中低产田改造,挖掘耕地潜力。80年代第二次土壤普查后,我们侧重于生物技术对中低产田改造,取得了明显的增产效益。但生物技术不能彻底排除中低产田障碍因素。 展开更多
关键词 管灌 中低产田改造 改造技术 出水口 旱工 砂漏 水泥管 沉砂池 人均耕地 管道
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Analysis of Antioxidant Characteristics in Seedling Roots of Sweetpotato(Ipomoea batatas(L.) Lam.) with Different Drought Tolerance under Simulated Drought Stress 被引量:3
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作者 姜瑶 汪宝卿 +4 位作者 解备涛 张海燕 段文学 王庆美 张立明 《Agricultural Science & Technology》 CAS 2016年第2期245-250,255,共7页
[Objective] Jishu 21 with strong drought tolerance and Jizishu 1 with weak drought tolerance were chosen to reveal antioxidant characteristics in seedling roots of sweetpotato with different drought tolerance. [Method... [Objective] Jishu 21 with strong drought tolerance and Jizishu 1 with weak drought tolerance were chosen to reveal antioxidant characteristics in seedling roots of sweetpotato with different drought tolerance. [Method] Active oxygen, antioxidant substances and antioxidant enzymes in seedling roots of sweetpotato with different drought tolerance were analyzed by hydroponics with PEG-6000 for simulating drought stress in the experiment. [Result] The results showed that under drought stress, H202 content and formation rate of 02_ in seedling roots of Jizishul were higher than Jishu 21 by 1.9% and 102.6%, respectively, the contents of Vc in seed- ing roots of Jizishu 1 and Jizishu 1 increased by 25.3% and 81.1%, respectively, and the contents of polyphenols increased by 24.8% and 37.6% in the two vari- eties, respectively. The increase amplitudes of Jizishu 1 were higher than Jishu 21 in the above indexes. Antioxidant enzyme activities were higher in seedling roots of Jisl^u 21 and Jizishul under drought stress than normal treatments; and among them, POD activity was the highest, while PPO activity was the lowest in all an- tioxidant enzymes. The increases of SOD, POD, APX and PPO activities in Jishu 21 were twice of those in Jizishul. The bands of SOD3, POD2, CAT1, APX2 and PPO2 changed obviously between the drought treatments of the two varieties. [Con- clusion] In conclusion, stronger drought tolerance in sweetpotato results in lower in- crease amplitudes of H202 content, formation rate of 02- and contents of Vc and polyphenols under drought stress, and the activities of antioxidant enzymes are stronger in seeding roots under drought stress; and the differences in antioxidant enzymes are mainly related to the changes of isoenzymes including SOD3, POD2, CAT1. APX2 and PPO2. 展开更多
关键词 Drought SWEETPOTATO Root Antioxidant enzyme ISOENZYME
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The Greening Construction and Technology of the Management in the Lop Nur Potash Mine
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作者 王世杰 孙永强 +3 位作者 李从娟 范敬龙 张恒 李步军 《Agricultural Science & Technology》 CAS 2016年第11期2516-2518,2524,共4页
Lop Nur potash mine greening projects is located in the heart of the Lop Nur, known as the "green zone ban". The project overcomes the extreme drought, high temperature, gale and dust salt and salt, and many other a... Lop Nur potash mine greening projects is located in the heart of the Lop Nur, known as the "green zone ban". The project overcomes the extreme drought, high temperature, gale and dust salt and salt, and many other adverse environmen- tal factors. Adopted the suitable salt improvement measures and management tech- nology, the artificial green has emerged in the sea of death. At the same time the greening project improved the office environment of mining area, and shaped ex- treme environment greening projects successful cases. 展开更多
关键词 Lop Nur Greening construction Management of maintenance Extreme drouaht: Hiah temperature Saline land
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Drought Resistance of Slope Pioneer Plant Magnolia multiflora 被引量:1
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作者 许翩翩 王建柱 《Agricultural Science & Technology》 CAS 2016年第9期2037-2041,2045,共6页
[Objective] This study aimed to reveal responses of Magnolia multiflora to soil drought stress. [Method] Pot experiment was employed to simulate drought stress, and photosynthetic and physiological indices of M. multi... [Objective] This study aimed to reveal responses of Magnolia multiflora to soil drought stress. [Method] Pot experiment was employed to simulate drought stress, and photosynthetic and physiological indices of M. multiflora were determined. [Result] The net photosynthetic rate (Pn) of M. multiflora did not change significantly under mild drought stress, and reduced significantly under moderate and severe drought stress. Drought stress reduced stomatal conductance (Gs), transpiration rate (Tr) and intercellular CO2 concentration (Ci), and compared with those in the control group, the Pn, Gs, Tr and Ci under severe drought stress declined by 61.04%, 86.27%, 87.77% and 42.63%, respectively. The malondialdehyde (MDA) content in M. multiflora leaves did not increase significantly under mild drought stress, and increased significantly under moderate and severe drought stress. The MDA content in M. multiflora leaves under severe drought stress was 1.63 times as high as that in the control group. The proline (Pro) and soluble sugar contents of M. multiflora increased significantly with the aggravation of drought stress, and those under severe drought stress were 8.06 times and 3.16 times respectively higher than those in the control group. [Conclusion] M. multiflora has a strong drought tolerance, and is suitable for growing in relatively arid environment. It can be used as candidate for vegetation restoration in hydropower engineering slope. 展开更多
关键词 Hydropower engineering Drought stress Magnolia multiflora Photosynthetic characteristics Physiological characteristics
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Could the 2012 Drought in Central US Have Been Anticipated?-A Review of NASA Working Group Research
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作者 S.-Y. Simon Wang Danny Barandiaran +8 位作者 Kyle Hilbum Paul Houser Bob Oglesby Ming Pan Rachel Pinker Joe Santanello Siegfried Schubert Hailan Wang Robert Gillies 《Journal of Earth Science and Engineering》 2014年第7期428-437,共10页
This paper summarizes research related to the 2012 record the NEWS (NASA (National Aeronautics and Space Administration) drought in the central United States conducted by members of Energy and Water cycle Study) W... This paper summarizes research related to the 2012 record the NEWS (NASA (National Aeronautics and Space Administration) drought in the central United States conducted by members of Energy and Water cycle Study) Working Group. Past drought patterns were analyzed for signal coherency with latest drought and the contribution of long-term trends in the Great Plains low-level jet, an important regional circulation feature of the spring rainy season in the Great Plains. Long-term changes in the seasonal transition from rainy spring into dry summer were also examined. Potential external forcing from radiative processes, soil-air interactions, and ocean teleconnections were assessed as contributors to the intensity of the drought. The atmospheric Rossby wave activity was found to be a potential source of predictability for the onset of drought. A probabilistic model was introduced and evaluated for its performance in predicting drought recovery in the Great Plains. 展开更多
关键词 Drought 2012 Great Plains climate variability and trends drought prediction.
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Evaluation of the Collapsibility of Soils in the Semiarid Region of Pernambuco, Brazil 被引量:1
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作者 Silvio Romero de Melo Ferreira Stela Fucale 《Journal of Civil Engineering and Architecture》 2014年第10期1285-1292,共8页
Some unsaturated soils may undergo volumetric changes when submitted to an increase in its water content or are inundated under applied loads. This behavior is related to the volumetric instability when the water cont... Some unsaturated soils may undergo volumetric changes when submitted to an increase in its water content or are inundated under applied loads. This behavior is related to the volumetric instability when the water content is changed. Natural collapsible soils in Brazil are generally found in alluvial, colluvial and residual soils. There are known occurrences of natural collapsible soils in many states of Brasil. In the last two decades, many public projects have been developed in areas where the occurrence of collapsible soils has been associated to geotechnical problems. The present paper devoted to study the collapsible soils in the state of Pernambuco which has been associated with large engineering projects such as housing and irrigation canals. The geotechnical investigation program included test with a field apparatus, called Expanso-colapsometer, which allows the measurement of the field settlements of a small 0.10 m of diameter plate inserted at any depth inside an auger boring hole. Reconnaissance borings with SPT (standard penetration test), investigation pits with undisturbed block sampling and disturbed samples for laboratory tests were also made in order to assess the type and characteristics of the soil. Field tests used the Expanso-colapsometer to measure the settlement of the soil in selected depths under controlled flooding. Laboratory work included double and standard oedometer tests with a controlled rate of water inflow of 1.0 mL/s. It was found that the volume change of the soils when flooded depends on their natural stress state (vertical stress, suction head and structure of soil). 展开更多
关键词 Collapsible soils field tests laboratory tests.
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Hydrological Responses to Climate Change in the Water Receiving Area of the Middle Route Project for South-to-North Water Transfer 被引量:1
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作者 XIA Jun ZENG Sidong +1 位作者 ZHANG Liping DU Hong 《Bulletin of the Chinese Academy of Sciences》 2012年第1期17-31,共15页
Climate change will lead to a significant alteration in the temporal and spatial pattern variation in the regional hydrological cycle, and the subsequent lack of water, environmental deterioration, floods and droughts... Climate change will lead to a significant alteration in the temporal and spatial pattern variation in the regional hydrological cycle, and the subsequent lack of water, environmental deterioration, floods and droughts etc. And it is especially remarkable in semi-humid and semi-arid region. In this paper, the impacts of climate change on the hydrological cycle were analyzed for the Hai River Basin, a semi-humid and semi-arid basin and also the water receiving area of the middle route of South-to-North Water Diversion project. Meanwhile it is the most vulnerable to climate change. Firstly, the linear regression and Mann-Kendall non-parametric test methods were used to analyze the change characteristics of the hydrological and meteorological elements for the period from 1960 to 2009. The results show a significant increase in temperature, while precipitation decreases slightly, and runoff decreases drastically over the past 50 years. Secondly, the applicability of SWAT (Soil and Water Assessment Tool) model based on the DEM (Digital Elevation Model), land use and soil type was verified in the basin. Results show the model performs well in this basin. Furthermore, the water balance model, Fu's theory and Koichiro's theory were used to calculate the actual evaporation, comparing to the simulated actual evaporation by SWAT model to validate the result for the lack of large-scale observed evaporation datasets. Possible reasons were also analyzed to explore the reasonable factor for the decline of the runoff. Finally the precipitation, temperature, runoff and evaporation response processes based on the IPCC AR4 multi-mode climate models and the verified SWAT model under different GHG emission scenarios (SRES-A2, AIB and B1) in the 21st century were discussed in three time periods: 2020s (2011-2040), 20S0s (2041-2070), 2080s (2071-2099). Results show that there are systematic positive trends for precipitation and temperature while the trends for runoff and evaporation will differ among sub-areas. The results will offer some references for adaptive water management in a changing environment, also including adaptation of a cross-basin water transfer project. 展开更多
关键词 climate change the Hai River Basin water cycle SWAT model
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介绍应邀来我国访问的印度著名统计学家马哈兰诺比斯教授
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作者 桑炳彦 《统计工作》 1957年第11期11-11,共1页
印度著名统计学家马哈兰诺比斯教授已应邀将来我国访问.我们趁此机会把他的生平和在统计方面的活动,向大家简单地介绍一下.
关键词 统计学家 印度科学院 教授 委员 统计顾问 副主席 旱工 定山 莫斯科 纽织
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