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Effects of Microbial Fertilizers on Soil Improvement and Wheat Growth Characteristics in Saline-alkali Land
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作者 Gen SONG Ziru LI +12 位作者 Baohai ZHANG Zhenhua JIA Jirong CUI Dingxin GUO Lili HAN Yanhong WU Jianlong FENG Yan GAO Mingying LIU Chunguang SONG Guojia JI Changsong WANG Zhiwei ZHANG 《Agricultural Biotechnology》 2024年第4期76-81,共6页
[Objectives]This study was conducted to further enrich the research on saline-alkali land improvement,and explore the effects of biological bacterial fertilizers containing Bacillus subtilis and Bacillus velezensis HM... [Objectives]This study was conducted to further enrich the research on saline-alkali land improvement,and explore the effects of biological bacterial fertilizers containing Bacillus subtilis and Bacillus velezensis HM-3 in saline-alkali land improvement and crop growth promotion.[Methods]Wheat was planted in saline-alkali land in Huanghua City,Hebei Province,and a mixed application experiment was carried out using biological agents from Hemiao Biotechnology Co.,Ltd.[Results]Compared with the field of control check(CK),water-soluble salts and pH value in the experimental fields decreased,and living bacteria count in the soil increased.Meanwhile,the economic characters of wheat in the experimental fields showed excellent performance,with yields increasing by 39.09%and 27.49%compared with the CK.It could be seen that the application of biological bacterial fertilizers achieved obvious effects of improving saline-alkali soil and increasing wheat yield.[Conclusions]In this study,the effects of biological bacterial fertilizers on saline-alkali land and wheat growth characters were clarified,providing some technical support and theoretical guidance for wheat planting in Huanghua saline-alkali land. 展开更多
关键词 Saline-alkali land Soil improvement WHEAT yield
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The Salt Reduction and Yield Increase Effects of Smashing Ridging Transforming Saline-alkali Land and Its Development Prospects 被引量:3
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作者 Wei Benhui Shen Zhangyou +5 位作者 Zhou Jia Zhou Lingzhi Gan Xiuqin Lao Chengying Li Yanying Hu Po 《Meteorological and Environmental Research》 CAS 2018年第4期112-115,120,共5页
Using smashing ridging tillage machine and smashing ridging technology invented by the authors, transformation test of saline-alkali land by smashing ridging was conducted respectively in Xinjiang and Shaanxi during 2... Using smashing ridging tillage machine and smashing ridging technology invented by the authors, transformation test of saline-alkali land by smashing ridging was conducted respectively in Xinjiang and Shaanxi during 2015 -2016. The results showed, in severe saline-alkali soil of Xin-jiang ,after growing cotton by smashing ridging, total salt in soil decreased by 31.31 %, cotton production increased by 48.80%, and salinity level declined from severe to moderate; in mild saline-alkali soil of Shaanxi, after growing summer corn by smashing ridging, total salt in soil decreased by 42.37%, corn yield increased by 34.83%, salinity degree changed from mild desalination to normal farmland ; in Ningxia, Inner Mongolia 7 Gansu ,Jilin, Henan, Hebei, and so on, smashing ridging tillage practice in different types of saline-alkali land was conducted ; according to the salt reduction and yield increase effects of saline-alkali land after smashing ridging, the development prospect of smashing ridging technique in improvement and application of saline-alkali land was proposed. 展开更多
关键词 Smashing ridging Saline-alkali land IMPROVEMENT Salt reduction yield increase PROSPECT
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Impacts of land disturbance and restoration on runoff production and sediment yield in the Chinese Loess Plateau 被引量:1
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作者 AI Ning WEI Tianxing +3 位作者 ZHU Qingke QIANG Fangfang MA Huan QIN Wei 《Journal of Arid Land》 SCIE CSCD 2017年第1期76-86,共11页
Land disturbance and land restoration are important factors influencing runoff production and sediment yield in the semi-arid loess regions of China. This study compared the runoff production and sediment yield during... Land disturbance and land restoration are important factors influencing runoff production and sediment yield in the semi-arid loess regions of China. This study compared the runoff production and sediment yield during the early stage after land disturbance(ESLD) with those during restoring stage after land disturbance(RSLD). Grey relational analysis was used to analyse the importance of each one of the influencing factors(vegetation, rainfall, soil and topography) in affecting the runoff production and sediment yield. Our results showed that during ESLD, topography was the most critical factor controlling the runoff production, while soil was the most important factor controlling the sediment yield. During RSLD, vegetation was more important in affecting runoff production, while rainfall was more important in affecting sediment yield. In additional, this study demonstrated that both the runoff production and the sediment yield can be effectively reduced by restoring vegetation on severely-disturbed lands, thus providing an important theoretical basis for better implementations of the Grain for Green Program. Our results revealed that the vegetation types of Hippophae rhamnoides+Pinus tabulaeformis and H. rhamnoides are better plant selections for land restoration in this area, especially for relatively gentle slopes(i.e., less than 20 degrees). 展开更多
关键词 land disturbance/ restoration grey relational analysis RUNOFF sediment yield Loess Plateau
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Establishment and Analysis of Regression Models between Sowing Time and Plant Productivity, Biological Yield of Forage Sorghum in Autumn Idle Land 被引量:1
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作者 ZHOU Han-zhang LIU Hong-xia +4 位作者 LIU Huan ZHOU Xin-jian WEI Zhi-min HOU Sheng-lin LI Shun-guo 《Agricultural Science & Technology》 CAS 2018年第1期51-58,共8页
[Objective]The aim was to establish the linear regression prediction models between sowing time and plant productivity, biological yield of forage sorghum in autumn idle land.[Method]The relationships between sowing t... [Objective]The aim was to establish the linear regression prediction models between sowing time and plant productivity, biological yield of forage sorghum in autumn idle land.[Method]The relationships between sowing time and plant productivity, biological yield of forage sorghum were simulated and compared by using field experiment and linear regression analysis.[Result] The sowing time had an important influence on the plant productivity and biological yield of forage sorghum in autumn idle land. The plant productivity and biological yield of forage sorghum both decreased with the delay of sowing time.The regression model between plant fresh weight and sowing time was ?fresh=0.618-0.015x; the regression model between plant dry weight and sowing time was ?dry=0.184-0.005x; and the regression model between biological yield and sowing time was yield=29 126.461-711.448x. During July 23rd to August 30th, when the sowing time was delayed by 1 day, the plant fresh weight of forage sorghum was reduced by 0.015 g, the plant dry weight was reduced by 0.005 g, and the yield was reduced by 711.448 kg/hm2. [Conclusion] The three regression models established in this study will provide theoretical support for the production of forage sorghum. 展开更多
关键词 Autumn idle land Forage sorghum Sowing time Plant productivity Biological yield Regression model Regression analysis
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Integrated assessment of extreme climate and landuse change impact on sediment yield in a mountainous transboundary watershed of India and Pakistan
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作者 Muhammad BABUR Sangam SHRESTHA +2 位作者 Binod BHATTA Avishek DATTA Hayat ULLAH 《Journal of Mountain Science》 SCIE CSCD 2020年第3期624-640,共17页
Assessment of climate and land use changes impact including extreme events on the sediment yield is vital for water and power stressed countries. Mangla Reservoir is the second-largest reservoir in Pakistan, and its c... Assessment of climate and land use changes impact including extreme events on the sediment yield is vital for water and power stressed countries. Mangla Reservoir is the second-largest reservoir in Pakistan, and its capacity is being reduced due to rapid sedimentation and will be threatened under climate and land use changes. This paper discusses the consequences of climate and land use change on sediment yield at Mangla Dam using General Circulation Models(GCMs), Land Change Modeler(LCM), Soil and Water Assessment Tool(SWAT) model after calibration and validation.Results show that over the historical period temperature is observed to increase by 0.10 o C/decade and forest cover is observed to reduce to the level of only 16% in 2007. Nevertheless, owing to the forest conservation policy, the forest cover raised back to 27% in 2012. Anticipated land use maps by using LCM of 2025, 2050 and 2100 showed that the forest cover will be 33%, 39.2%, and, 53.7%, respectively. All seven GCMs projected the increase in temperature and five GCMs projected an increase in precipitation,however, two GCMs projected a decrease in precipitation. Owing to climate change, land use change and combined impact of climate and land use change on annual sediment yield(2011-2100) may vary from-42.9% to 39.4%, 0% to-27.3% and,-73%to 39.4%, respectively. Under climate change scenarios projected sediment yield is mainly linked with extreme events and is expected to increase with the increase in extreme events. Under land use change scenarios projected sediment yield is mainly linked with the forest cover and is expected to decrease with the increase in forest cover. The results of this study are beneficial for planners, watershed managers and policymakers to mitigate the impacts of climate and land use changes to enhance reservoir life by reducing the sediment yield. 展开更多
关键词 Climate change and land use changes EXTREME events Terrset LCM SEDIMENT yield
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Comparative productivity of Prosopis cineraria and Tecomella undulata based agroforestry systems in degraded lands of Indian Desert
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作者 G. Singh 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期144-150,I0003,共8页
Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L. and Tecomella undulata L. and yields of Vigna radiata (L) in agroforestry systems in degraded lands of Indian Desert... Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L. and Tecomella undulata L. and yields of Vigna radiata (L) in agroforestry systems in degraded lands of Indian Desert. Potential competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots. The plots size were 16 m × 18 m (D1), 20 m × 18 m (D2) and 32 m × 18 m (D3) with tree densities of 208, 138 and 104 trees.ha^-1 after June 2002, respectively. Results showed that tree height increased by 3% to 7% during June 2002 to June 2004. Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P. cineraria and T. undulata in two years period. The increase in crown diameter was 9% to 18% in P. cineraria and 11% to 16% in T. undulata. Tree growth was relatively greater in 2002 than in 2003. Yield of V. radiata increased linearly from D1 to D3 plots. Lowest soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting zone. Concentrations of soil organic matters and NH4-N were the highest (p〈0.05) in 0-25 cm soil layer. P. cineraria was more beneficial than T. undulata in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural land. The yield of agricultural crop increased when density of tree species was appropriate (i.e., optimum tree density), though it varied with tree size and depended upon resource availability. The result indicated bio-economic benefits of optimum density of P. cineraria and T. undulata over traditional practices of maintaining random trees in farming system in arid zones. 展开更多
关键词 arid region crop yield land productivity soil water and nutrients tree growth
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Comparative productivity of Prosopis cineraria and Tecomella undulata based agroforestry systems in degraded lands of Indian Desert
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作者 G. Singh 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期144-150,共7页
Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L.and Tecomella undulata L.and yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian Desert.Pote... Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L.and Tecomella undulata L.and yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian Desert.Potential competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots.The plots size were 16 m × 18 m(D1), 20 m × 18 m(D2) and 32 m × 18 m(D3) with tree densities of 208, 138 and 104 trees·ha-1 after June 2002, respectively.Results showed that tree height increased by 3% to 7% during June 2002 to June 2004.Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P.cineraria and T.undulata in two years period.The increase in crown diameter was 9% to 18% in P.cineraria and 11% to 16% in T.undulata.Tree growth was relatively greater in 2002 than in 2003.Yield of V.radiata increased linearly from D1 to D3 plots.Lowest soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting zone.Concentrations of soil organic matters and NH4-N were the highest(p<0.05) in 0-25 cm soil layer.P.cineraria was more beneficial than T.undulata in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural land.The yield of agricultural crop increased when density of tree species was appropriate(i.e., optimum tree density), though it varied with tree size and depended upon resource availability.The result indicated bio-economic benefits of optimum density of P.cineraria and T.undulata over traditional practices of maintaining random trees in farming system in arid zones. 展开更多
关键词 arid region crop yield land productivity soil water and nutrients tree growth
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The supporting capability of Water and land resources for sustainable increase of yield in North China Plain
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作者 ZHANG HongyeInstitute of Geography, CAS, Beijing 100101 CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第2期80-85,共6页
The potential of yield increase in the North China Plain is about 30 billion kg by ameliorating the low yield and medium low yield farmlands and 4 billion kg by reclaiming unused land. Water shortage will be the main ... The potential of yield increase in the North China Plain is about 30 billion kg by ameliorating the low yield and medium low yield farmlands and 4 billion kg by reclaiming unused land. Water shortage will be the main limitation to the further increase of grain crop yield. The amount of water shortage is 8 200 million m3 at present, and will be 17 720 million m3 in 2 000. Yield increase can not be realized by using more water in the future. Other factors such as decrease of the area of cultivated land and the grain crop growing area, deterioration of environment and destruction of resources will also affect the development of grain production. Some suggestions have been proposed in the paper for attaining sustainable increase of yield in the plain. 展开更多
关键词 North China Plain yield increase grain crop water and land resources
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Effects of Sowing Time on Biological Yield of Forage Sorghum[Sorghum bicolor(L.) Moench] in Autumn Idle Land
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作者 Hanzhang ZHOU Huan LIU +4 位作者 Xinjian ZHOU Haiyan JIA Zhimin WEI Shunguo LI Shenglin HOU 《Agricultural Biotechnology》 CAS 2017年第5期38-42,共5页
[Objective] This study was performed to explore the correlation between sowing time and biological yield of forage sorghum in autumn. [Method] In field trials,forage sorghum was sown on six different dates( July 23,Ju... [Objective] This study was performed to explore the correlation between sowing time and biological yield of forage sorghum in autumn. [Method] In field trials,forage sorghum was sown on six different dates( July 23,July 29,August 6,August 14,August 22 and August 30). Then,seedling emergence stage,jointing stage,booting stage,heading stage,filling stage,fresh weight and dry weight in each plot were observed or measured. Finally,linear regression analysis on these data was carried out to deduce the correlation between sowing date and biological yield of forage sorghum. [Result]Sowing time showed a significant influence on biological yield of forage sorghum in idle land,and the biological yield of forage sorghum linearly decreased with the postponement of sowing time. The relationship between sowing time and biological yield of forage sorghum can be represented by the regression equations y_(fresh)= 196. 646-4. 625 x and y_(dry)= 58. 253-1. 423 x,wherein,x is sowing date,y_(fresh)and y_(dry)are the fresh weight and dry weight of forage sorghum. On average,the fresh weight of forage sorghum was reduced by 4. 625 kg/20 m^2,and dry weight by 1. 423 kg/20 m^2,when the sowing date was delayed by one day from July 23 to August 30. [Conclusion]The regression models built in this study will provide a theoretical basis for improving the yield of forage sorghum in autumn idle land. 展开更多
关键词 AUTUMN IDLE land FORAGE SORGHUM SOWING time Biological yield Regression analysis
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Effect of Autumn Cutting Date on Regrowth, Turning Green, Yield and Quality of <i>Leymus chinensis</i>Grassland in Songnen Plain, Northeast China 被引量:1
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作者 Yantao Song &ensp +1 位作者 Wuyunna Daowei Zhou 《American Journal of Plant Sciences》 2018年第2期185-195,共11页
A field study was carried out to quantify the effects of different cutting time on Leymus chinensis population and community characteristic in Songnen grassland of northeast China from August, 2006 to August, 2007. Th... A field study was carried out to quantify the effects of different cutting time on Leymus chinensis population and community characteristic in Songnen grassland of northeast China from August, 2006 to August, 2007. The treatment interval was ten days with the remaining stubble height of 5 cm from 15th August to 4th October in 2006. Results showed that the L. chinensis made up about 90% of the dry matter of aboveground biomass, and there were about ten species in the L. chinensis community in the 1 m × 1 m plot. The L. chinensis and Kalimeris integrifolia regrew rapidly after autumn cutting in 2016. In the second year, the coefficients of the community similarity were high between the different cutting time treatments. The density, height, aboveground biomass, stem/leaf ratio, and crude protein of L. chinensis were not significant at the turning green stage and harvesting stage, the companion species of L. chinensis community contained higher crude protein, but the crude protein of the plant community were not significant. Thus, considering the weather factor for haymaking, the harvest dates should be concentrated from the middle ten days of August to the first ten days in September. 展开更多
关键词 LEYMUS chinensis AUTUMN Cutting HAY yield Quality Songnen Grass-land
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Assessing the Effect of Natural Controls and Land Use Change on Sediment Yield in a Major Andean River:The Magdalena Drainage Basin,Colombia 被引量:4
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作者 Juan Dario +5 位作者 Restrepo James P. M. Syvitski 方海燕(译) 《AMBIO-人类环境杂志》 2006年第2期65-74,4,共10页
马格达莱纳河是哥伦比亚安第斯山区的一个世界级的河流网络,该河流年产沙量约为150Mt,是全世界10大主要产沙河流之一。在本研究中,我们探讨主要自然因子和人类活动对马格达莱纳河流域产沙模式的影响,重建该区森林砍伐和农业活动时... 马格达莱纳河是哥伦比亚安第斯山区的一个世界级的河流网络,该河流年产沙量约为150Mt,是全世界10大主要产沙河流之一。在本研究中,我们探讨主要自然因子和人类活动对马格达莱纳河流域产沙模式的影响,重建该区森林砍伐和农业活动时空模式,探讨土地利用变化与产沙趋势的关系。我们的研究结果表明,整个马格达莱纳河流域的产沙量可以用自然变量(包括径流量和最大河水流量)来解释。这两个因子解释了产沙量58%的变化。含沙率和土地利用的时间分析表明,在过去10~20年里流域侵蚀呈现增加的趋势。许多人类活动的影响,包括森林覆被在20年里减小了近40%.农业和牧场增加了65%、土壤保持差、开矿活动,以及城市化的加速,都促进了该地区域尺度上产沙量的增加。 展开更多
关键词 Assessing the Effect of Natural Controls and land Use Change on Sediment yield in a Major Andean River
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Relationship between Land Indices and Yield of Oil Palm in Peninsular Malaysia
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作者 Adzemi Mat Arshad Mustika Edi Armanto 《Journal of Environmental Science and Engineering(B)》 2012年第5期663-667,共5页
Twenty four soils of Peninsular Malaysia derived from a varied geology and providing a range of particle size classes as well as different profile development stages were chosen for the study. Land characteristics and... Twenty four soils of Peninsular Malaysia derived from a varied geology and providing a range of particle size classes as well as different profile development stages were chosen for the study. Land characteristics and land qualities were used to determine the land suitability for oil palm cultivation. The results show that land characteristics have stronger influence on the yield of oil palm compared to land qualities. The use of the Framework for Land Evaluation together with the combined limitation-parametric approach enabled a more meaningful interpretation of the land units. Results demonstrated that land characteristics are recommended for land evaluation for oil palm cultivation. 展开更多
关键词 land characteristics land qualities oil palm yield Peninsular Malaysia.
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Land Use Change Effects on Discharge and Sediment Yield of Song Cau Catchment in Northern Vietnam
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作者 D.B. Phan C.C. WU S.C. Hsieh 《Journal of Environmental Science and Engineering》 2011年第1期92-101,共10页
The purpose of this paper is to implement "Soil and Water Assessment Tool (SWAT)" model to examine the effects of land use change scenarios; associated with crop rotations and special cultivation techniques most s... The purpose of this paper is to implement "Soil and Water Assessment Tool (SWAT)" model to examine the effects of land use change scenarios; associated with crop rotations and special cultivation techniques most susceptible to erosion; exert on runoff discharge and sediment yield from Song Cau catchment in Northern Viet Nam. All scenarios' simulations resulted in a decrease of soil losses and sediment yield comparing to the current land use status. SWAT successfully predicted soil losses from different HRUs that caused significant sediment yield, and it predicted explicitly the consequences of non-structural mitigation measures against erosion. 展开更多
关键词 SWAT agricultural land sediment yield land use change scenarios
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Effects of Subsoiling on Some Soil Physical Properties and Wheat Yield in a Dry Land Ecological Condition
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作者 S. Afzalinia A. A. Solhjou I. Eskandari 《Journal of Agricultural Science and Technology(A)》 2011年第6期842-847,共6页
In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid dow... In order to evaluate the effect of subsoiling on the soil physical properties and wheat yield in dry land conditions, this research was conducted in Mamassani area of Fars province in Iran. The experiment was laid down in the form of a complete block experimental design with four treatments and four replications for three years. Treatments included: (1) conventional tillage without using subsoiler which was control treatment (So); (2) using subsoiler with the shank space of 40 cm which was equal to the subsoiling depth (SO; (3) using subsoiler with the shank space of 60 cm which was 1.5 times of the subsoiling depth (S2); and (4) using subsoiler with the shank space of 80 cm which was 2 times of the subsoiling depth (S3). Subsoiling depth was set at 40 cm which was the lower limit of the hard pan depth in the soil. Soil cone index, soil bulk density, soil moisture content, wheat yield, and yield components were measured in this study and SAS software was used to analyze the collected data. Results showed that subsoiling decreased the soil bulk density and cone index, and increased water retention of the soil. Results also revealed that applying subsoiler increased wheat yield and yield components in our dry land conditions. Since subsoiling improved soil physical conditions and increases wheat yield, applying subsoiler in such a dry land conditions is therefore recommended. Results of this study also showed that subsoiling with the shank space of 40 cm and 60 cm had better performance compared to the shank space of 80 cm. On the other hand, shank space of 40 cm reduced the subsoiler effective working width and consequently effective field capacity. Therefore, subsoiler with a shank space of 60 cm is recommended for application in dry land soils of our type. 展开更多
关键词 SUBSOILING soil physical properties dry land conditions wheat yield.
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Results of Testing Maize Hybrids on Lands Shifting from Rice-Growing Areas of Less Efficiency in the Mekong Delta
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作者 Le Quy Kha 《Journal of Agricultural Science and Technology(B)》 2015年第4期241-246,共6页
Forecasters predict that by 2020 there will be 4.5 or 5 million tons per annum maize supply deficiency in Vietnam. As a result of this projection, the government responded by shifting 80,000 ha of low-efficiency rice ... Forecasters predict that by 2020 there will be 4.5 or 5 million tons per annum maize supply deficiency in Vietnam. As a result of this projection, the government responded by shifting 80,000 ha of low-efficiency rice production areas into maize production (2014-2015) and this area of production for maize is expected to increase to 150,000 ha by 2016-2020. Nevertheless, not all commercial maize hybrids could be suitable for rice-growing land in the Mekong Delta and a national project of hybrid maize development for Mekong Delta has been conducted since early 2014. In the project, yield trials of 20 maize hybrids, sourced from Vietnamese institutions and the private sector including Syngenta (NK67) and Dekalb (DK9901), were sown in Dong Thap, Hau Giang and Long An provinces situated in the Mekong Delta, in minor acid sulphate soils with a pH of 5.0-5.5. The trial included three replications in an Alpha lattice design conducted during spring-summer in 2014. The hybrids flowered at 50-52 d after planting and physiologically matured between 93-97 d after planting. This suggested they would be suitable for cropping systems, which was comprised of three seasons per year. To determine which hybrid is best suited for the region, researchers evaluated yield and ear characteristics. The average yield of the genotypes across locations was 52.03, 54.92 and 57.60 quintals/ha, respectively, and the heritability of genotypes in each location was 0.51, 0.81 and 0.61, respectively. The mean yield of DK9901 was 58.19 quintals/ha, ranking the 7th among 20 hybrids, and NK67 was 47.58 quintals/ha, ranking the 19th. The grand mean was 54.92 quintals/ha and heritability for all genotypes was 0.79. The highest yield was produced by the Southern seed company hybrid SSC474 (69.39 quintals/ha), which yielded significantly more maize than DK9901 (58.19 quintals/ha) at P 〈 0.05, followed by VS71 from National Maize Research Institute (NMRI) at 63.52 quintals/ha, and LCH9A from NMRI at 63.39 quintals/ha. Although the yield of the VS71 hybrid was greater than the DK9901 hybrid, the ear characteristics were less desirable. Therefore, after comparing these hybrids, it was concluded that SSC474 and LCH9A were the two most suitable hybrids to produce in the Mekong Delta. 展开更多
关键词 Maize (Zea mays L.) hybrid Mekong Delta rice-growing land yield trials.
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Impact of Teak (Tectona grandis Linn.) Thinning Out and Peacock-plume [Paraserianthes falcataria L. (1. Nielsen)] Harvesting on Mineral Cycle, Pod Rot Incidence, Changing of Cocoa Yield, and Land Productivity in Indonesia
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作者 Aloysius Adi Prawoto 《Journal of Agricultural Science and Technology(A)》 2012年第4期438-448,共11页
In 2009, Indonesia was included in a group of the ten biggest countries emitting greenhouse gases, and forest sector contributes 85%. This forest exploitation should be stopped, and by this research the industrial woo... In 2009, Indonesia was included in a group of the ten biggest countries emitting greenhouse gases, and forest sector contributes 85%. This forest exploitation should be stopped, and by this research the industrial wood species with special planting pattern was used as cocoa shade trees. The experiment was conducted in East Java, Indonesia, altitude 45 m above sea level using four planting patterns, i.e. (A) cocoa-Tectona grandis Linn. 3 m x 6 m, (B) cocoa-T, grandis 6 m x 4.2 m ~ 4.2 m (triangle), (C) cocoa-Paraserianthesfalcataria L. (I. Nielsen) 3 m ~ 6 m, and (D) cocoa-Leucaena sp. 3 m ~ 6 m (control). Cocoa was planted in 3 m ~ 3 m distance; between rows of teak and Paraserianthes was planted. Cassia surithensis of 3 m distance in the row, as reserve shade trees. At 6 year old, Paraserianthes was harvested, and at 7 year old, teak trees were thinned out 50% population for A and 66.7% for B treatments. The result showed that cocoa agroforestry by using timber trees in regular planting pattern and accurate spacing did not decrease cocoa yield but improved land productivity. Paraserianthes harvesting produced 0.71 m3 timber and the price was US$38.0-US $40.0 per tree, while teak thinning out produced 0.07 m3 wood per tree and it cost was US$5 per tree. From 108 Paraserianthes trees harvested, 81 cocoa trees were affected, 11.9% were seriously damage, 6.85% were medium damage, and 5.36% were light damage. On the other hand, teak spacing did not cause serious damage on cocoa trees. Biomass of harvested Paraserianthes and teak supplied back to soil 543 g and 250 g per tree respectively for equalities to total urea, SP 36, KC1, Kieserite and Dolomite. Paraserianthes harvest and teak thinning out made microclimate to be warmer, humidity to be lower, so pod rot incidence become lower and pod yield was improved, namely 71% and 27.25% for Paraserianthes plot and teak plot, respectively. Harvesting of Paraserianthes produced benefit/cost plot of 43.63, and teak thinning out of 3.60. The revenue obtained from timber sales easily offset the costs of damage of the cocoa crop. It is concluded that by using accurate planting pattern, cocoa area could produce industrial timber without sacrifying cocoa production and exactly improve land productivity. 展开更多
关键词 Cocoa timber shade trees thinning out pod rot mineral cycle yield land productivity benefit/cost.
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Spatial Distribution Assessment and Source Apportionment of Land-Based Pollutant Yield from Qingdao, China
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作者 SU Ying LIANG Shengkang +1 位作者 ZHANG Peng WANG Xiulin 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期151-158,共8页
The spatial distribution of chemical oxygen demand(COD) and total nitrogen(TN) yield from Qingdao are studied by comparing pollutant yield amount, densities and spatial aggregation(Getis-Ord indexes) among the land-ba... The spatial distribution of chemical oxygen demand(COD) and total nitrogen(TN) yield from Qingdao are studied by comparing pollutant yield amount, densities and spatial aggregation(Getis-Ord indexes) among the land-based pollutant source regions(PSRs) entering the three sub-seas(i.e. the Jiaozhou Bay(JZB), other coastal area in the Yellow Sea(OCAYS) and Laizhou Bay(LZB), respectively). Industrial composition of the loads are also studied by comparing pollutant yield among the sources of agriculture, rural domesticity, industry, urban domesticity and service, and calculation of Gini coefficient. Results show that spatial distribution of COD and TN yield from Qingdao are extremely unbalanced. The JZB, with less than 3% of the total coastal sea area of Qingdao, received 62% COD load and 65% TN yield from Qingdao, while the OCAYS, with more than 97% area, only received 23% COD and 20% TN, which consist with the much worsen water quality of JZB than that of OCAYS. On the other hand, the source apportionment of COD and TN loads in the PSRs entering JZB and the OCAYS was similar. The agricultural and domestic sources with high pollution intensity account for more than 80%, while the industrial and service sources with low pollution intensity account for less than 20%. While Gini coefficients, COD 0.81 and TN 0.84 which are much higher than the ‘imbalance' threshold of 0.4, show the uneven industrial structure of Qingdao. These results may be useful in the determination of land-based pollution total amount control at the PSR level. 展开更多
关键词 Qingdao land-based POLLUTANT POLLUTANT yield POLLUTION INTENSITY industrial structure
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The Type of Low-yielding Fields,Using Direction and Land Fertility Building Measures in Suiping County
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作者 Jiuyi HU 《Asian Agricultural Research》 2014年第11期81-82,86,共3页
Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,s... Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,soil management,and soil nutrients concerning various types of low-yielding fields in the county. In accordance with the dominant soil constraint factors and main direction of improvement,the lowyielding fields in the county are divided into four types: irrigation improvement type,waterlogging drainage type,barren soil fertilization and barrier layer type. Finally this paper offers specific guidance on the construction of arable land. 展开更多
关键词 TYPE of low-yielding FIELDS USING direction land f
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有土斯有粮:高标准农田建设提高了粮食单产吗? 被引量:6
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作者 钱龙 杨光 钟钰 《南京农业大学学报(社会科学版)》 CSSCI 北大核心 2024年第1期132-143,共12页
作为“藏粮于地,藏粮于技”战略的重要政策实践,高标准农田建设被期待能够有效实现粮食增产和更好保障国家粮食安全。基于27个省(市、自治区)的面板数据,探索了高标准农田建设对粮食单产的影响及其可能机制。研究发现:(1)高标准农田建... 作为“藏粮于地,藏粮于技”战略的重要政策实践,高标准农田建设被期待能够有效实现粮食增产和更好保障国家粮食安全。基于27个省(市、自治区)的面板数据,探索了高标准农田建设对粮食单产的影响及其可能机制。研究发现:(1)高标准农田建设能显著提高粮食单产。替换核心变量、进行非参数估计和考虑内生性的稳健性检验,均证实上述发现可信。(2)机制验证表明,高标准农田建设主要通过提升规模经营、促进技术进步和降低生产风险三大路径来提高粮食单产。(3)异质性分析发现,高标准农田建设对起伏度较小地形、粮食主产区、较发达地区的粮食单产促进效应更大。研究结果表明高标准农田建设确实是夯实粮食安全根基的重要举措,需扎实推进新一轮高标准农田建设工作。 展开更多
关键词 “藏粮于地 藏粮于技”战略 高标准农田建设 粮食单产 粮食安全
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宽幅条播对燕麦间作箭筈豌豆产量及种间关系的影响
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作者 王英 李立军 +4 位作者 韩雪 赵鑫瑶 韩冬雨 张宏杰 李嘉琪 《麦类作物学报》 CAS CSCD 北大核心 2024年第6期795-802,共8页
为明确宽幅条播对燕麦‖箭筈豌豆间作系统生产力的影响,在常规条播和宽幅条播两种播种方式下设置燕麦单作、箭筈豌豆单作及燕麦‖箭筈豌豆间作三种种植方式,比较分析了不同处理间作物产量、种间关系及燕麦产量构成因素的差异。结果表明... 为明确宽幅条播对燕麦‖箭筈豌豆间作系统生产力的影响,在常规条播和宽幅条播两种播种方式下设置燕麦单作、箭筈豌豆单作及燕麦‖箭筈豌豆间作三种种植方式,比较分析了不同处理间作物产量、种间关系及燕麦产量构成因素的差异。结果表明,与单作相比,间作燕麦的饲草及籽粒产量显著提高,增幅分别为24.25%~32.77%和27.44%~32.69%,而间作箭筈豌豆的饲草及籽粒产量降低为7.16%~8.08%和2.80%~5.48%。宽幅条播可提高燕麦及箭筈豌豆产量,宽幅条播间作饲草和籽粒产量的土地当量比较常规条播间作分别提高0.03和0.06。在间作中,燕麦的侵占力大于0,实际产量损失大于1,竞争比率大于1,且燕麦的相对拥挤系数大于箭筈豌豆,说明燕麦在间作系统中处于竞争优势。间作燕麦穗数、穗粒数和穗重较单作显著提高,平均增幅分别为24.23%、14.84%和17.43%,其中宽幅条播间作处理的穗粒数、公顷穗数和穗重均显著高于其他处理。由此可见,宽幅条播下通过与箭筈豌豆间作,可提高燕麦生产力和土地资源利用效率。 展开更多
关键词 燕麦 箭筈豌豆 宽幅条播 间作 籽粒产量 产量构成因素 土地当量比 实际产量损失
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