期刊文献+
共找到1,150篇文章
< 1 2 58 >
每页显示 20 50 100
Effects of N, P and K on Output and Nutrient Cycle of Vegetables in Greenhouses
1
作者 朱静华 李玉华 +1 位作者 李明悦 高伟 《Agricultural Science & Technology》 CAS 2013年第7期1011-1016,共6页
ObjectiveThe aim was to increase farmers’ income and reduce the waste of fertilizer by exploring effects of N, P and K fertilizations on vegetable yields and the accumulation of N, P and K in vegetable and soils. Met... ObjectiveThe aim was to increase farmers’ income and reduce the waste of fertilizer by exploring effects of N, P and K fertilizations on vegetable yields and the accumulation of N, P and K in vegetable and soils. MethodThe fertilization tests were conducted on tomato, cauliflower and celery in greenhouses. ResultWhen N, P and K were not applied in tomato, cauliflower or celery, the yields reduced in 6.0%-13.8% and total annual income reduced by 39 220, 36 902 and 22 023 yuan/hm 2 respectively, suggesting that N, P and K are limiting factors of yield. The absorbed N amounts of tomato and cauliflower were higher compared with celery; the absorbed P amount of cauliflower was higher compared with tomato and celery; the absorbed K amount of tomato was the highest, followed by celery and cauliflower. The absorbed N in tomato fruit was lower than that of cauliflower and the absorbed N amount of other parts of tomato was also lower. Furthermore, the absorbed amounts of P and K by tomato and cauliflower fruits were higher than it absorbed by the other parts, especially the absorbed of K was significantly high. Total absorbed amounts of N, P and K from high to low were cauliflower, tomato and celery. After harvesting of tomato, cauliflower and celery, N, P and K in soils were all higher compared with soils before planting. Influenced by fertilizers, residual N content in soils grown with tomato and residual P content in soils grown with celery both doubled compared with base soils. Cauliflower plants were not applied with organic fertilizer, and residual N and K contents in soils were lower compared with tomato and celery. ConclusionResidual P content in soils is higher, which is a kind of waste and would cause pollution on soils. It is necessary to improve the proportion of organic and inorganic fertilizers in fertilization. 展开更多
关键词 Rotation system of greenhouse vegetable YIELD n uptake p uptake k uptake Soil residues
下载PDF
GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N) 被引量:1
2
作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUnDEDnESS unit ball
下载PDF
Effects of N,P and K Amounts on Yield Traits of Wheat in Wheat-cotton Intercropping System
3
作者 王树林 祁虹 +4 位作者 王燕 张谦 冯国艺 林永增 梁青龙 《Agricultural Science & Technology》 CAS 2016年第7期1645-1647,1670,共4页
[Objective] This study was conducted to investigate the demands for N, P and K by wheat in wheat cotton intercropping system in high-fertility field of Hebei Province. [Method] The experiment adopted randomized block ... [Objective] This study was conducted to investigate the demands for N, P and K by wheat in wheat cotton intercropping system in high-fertility field of Hebei Province. [Method] The experiment adopted randomized block arrangement. Five treatments (0, 75, 150, 225 and 300 kg/hm2) were designed for N, P and K. Wheat tillering, ear number, yield and yield components were investigated. [Result] Wheat yield increased significantly with the application of N fertilizer. The number of ears per unit area, number of grains per ear, 1 000-grain weight and yield were im- proved with N increasing. P fertilizer improved wheat yield at a certain degree, but K had no effect on wheat yield. ]Conclusion] The optimum fertilization for wheat-cot- ton intercropping system was N at 225-300 kg/hm2 and P2Os at 150 kg/hm2; and there is no need to apply K. 展开更多
关键词 Wheat-cotton Intercropping System n p and k WHEAT YIELD
下载PDF
Ability of Ectomycorrhizal FUngus Laccaria biclor S238N to Increase the Growth of Douglas FIr Seedlings and Their Phosphorus and Potassium Uptake 被引量:19
4
作者 HUANGJIANGUO F.LAPEYRIE 《Pedosphere》 SCIE CAS CSCD 1996年第3期217-224,共8页
Ectomycorrhizal fungus Laccaria bicolor S238N,isolated from a forest soil in central France in 1990s,has demonstrated unequivocally and ability to promote pine growth.In the present nursery bed experiment,the ability ... Ectomycorrhizal fungus Laccaria bicolor S238N,isolated from a forest soil in central France in 1990s,has demonstrated unequivocally and ability to promote pine growth.In the present nursery bed experiment,the ability of this ectomycorrhizal fungus to increase growth and P and K uptake of Douglas Fir seedlings (Zone 22) was examined.Growth of inoculated seedlings was over twice(plant height) and three times (biomass)that of non-inoculated ones.Similarly,both the concentrations and the amounts of P and K uptake by seedlings were significantly increased by fungal inoculation,indicating the improvement of P and K nutrition in mycorrhizal seedlings.In contrast,Al-P in the soils was decreased obviously by plants,especially by mycorrhizas,suggesting utilization of this soil P pool by plants and more efficient Al-P mobilization by mycorrhizas than by nomycorrhizas.Moreover,K extracted by 1mol/L HCl following consecutive extraction of H2O and CH3COONH4,which may not be plant available,could be utilized by fungus colonied roots.This could be explained by the release of protons and oxalate by hypae which leads to replacement of interlayer K in nonexpanded 2:1 clay minerals and bio-weathering of phyllosilicates. 展开更多
关键词 外生菌根真菌 黄杉树苗 p吸收 k吸收 促生长作用 S238n
下载PDF
Effects of Regulation of C/N Ratio Wheat Straw Application on Nitrogen,Phosphorus and Potassium Uptake in Tobacco 被引量:13
5
作者 段宗颜 王瑞宝 +3 位作者 鲁耀 殷寿安 胡万里 陈拾华 《Agricultural Science & Technology》 CAS 2010年第5期77-81,共5页
[Objective]The aim was to study the effects of regulation of C/N ratio wheat straw application on tobacco nitrogen,phosphorus and potassium uptake. [Method]Effects of regulation C/N ratio wheat straw application on th... [Objective]The aim was to study the effects of regulation of C/N ratio wheat straw application on tobacco nitrogen,phosphorus and potassium uptake. [Method]Effects of regulation C/N ratio wheat straw application on the flue-cured tobacco yield,output value,nitrogen,phosphorus and potassium content and cumulative uptake of the upper,middle and bottom leaf were studied by using the field plot experiments at Banqiao town,Qujing city,Yunnan Province during the 2008-2009 summer growing seasons. [Result]The results showed that the application of wheat straw alone or after C/N regulation,could significantly increase tobacco production,potassium content,the potassium and nitrogen accumulation amount of leaf,and was more conducive to the potassium uptake of tobacco leaf with wheat straw application after C/N regulation. Compared with non-straw application,the yield of tobacco increased by 6.59%,3.58%,5.98%,8.80% with application of wheat straw alone,wheat straw and vetch,wheat straw and oilseed cake,wheat straw and urea nitrogen,the potassium content in tobacco leaf increased by 3.85%,7.76%,8.82%,11.21%,respectively,the total potassium cumulative amount of leaf increased by 10.71%,11.62%,15.32% ,21.01% and the total nitrogen cumulative amount increased by 9.76%,1.22%,8.14%,14.00%. However,the differences of tobacco leaf nitrogen content among the different treatments were not significant,the phosphorus uptake of tobacco leaf decreased. [Conclusion]application of high C/N ratio wheat straw in flue-cured tobacco production,which should be concerned not only to adjust C/N ratio by adding nitrogen,but also considering additional phosphorus application. 展开更多
关键词 Wheat straw C/n ratio regulation Flue-cured tobacco n p k uptake
下载PDF
Effects of N,P and K Fertilizers on Growth of Clover Nitrogen-fixing Rhizobia and Soil Fertility after Plantation
6
作者 刘亚柏 朱庆锋 +1 位作者 毕道杰 王润芳 《Agricultural Science & Technology》 CAS 2016年第4期906-911,915,共7页
In order to develop organic rice and increase paddy soil fertility by cloverorganic rice rotation, the effects of N, P and K fertilizers on growth of clover nitrogen-fixing rhizobia and soil fertility after plantation... In order to develop organic rice and increase paddy soil fertility by cloverorganic rice rotation, the effects of N, P and K fertilizers on growth of clover nitrogen-fixing rhizobia and soil fertility after plantation were investigated, thereby providing certain reference for reasonable cultivation of clover and improvement of soil fertility. A two-year experiment was conducted from 2012 to 2013. The clover was cultivated after rice every year, and different levels of N, P and K fertilizers were applied before winter. In the treatment group, no fertilizer was applied. The effects of different fertilizers and different application amounts on clover yield, nitrogen-fixing rhizobia quantity, nitrogen-fixing rhizobia weight and soil fertility after plantation were analyzed. The results showed that the application of N, P and K fertilizers in the early stage had significantly effect on the growth of clover. When the application amount of N fertilizer was 75 kg/hm^2(N 46%), the clover yield, nitrogen-fixing rhizobia quantity and nitrogen-fixing rhizobia weight were highest. The soil nitrogen content after plantation increased with the increase of the application amount of N fertilizer, while the P and K content decreased and then increased with the increased application amounts. Soil available P content increased with the increased application amounts of N and P fertilizers, but it did not change significantly with the increased application amount of K fertilizer. Soil available K content increased first and then decreased with the increased application amounts of N and P fertilizers.When the application amounts of N and P fertilizers were 150(N 46%) and 300(P_2O_5 12%) kg/hm^2, soil available K content reached the maximum. Soil organic matter content increased with the increased application amounts of N, P and K fertilizers. Therefore, in the cultivation of clover, appropriate application of N, P and K fertilizers in the early stage can improve clover yield and soil fertility. 展开更多
关键词 n fertilizer p fertilizer k fertilizer CLOVER nitrogen-fixing rhizobia Soil fertility
下载PDF
A Preliminary Study on Dynamics and Models of N,P,K Absorption for High-Yield Cotton 被引量:6
7
作者 WANGKe-ru LIShao-kun +3 位作者 CAOLian-pu SONGGuang-jie CHENGang CAOSuan-zhu 《Agricultural Sciences in China》 CAS CSCD 2003年第7期752-759,共8页
The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of ... The field experiments were carried out to investigate the dynamics and models of N, P and K absorption for the cotton plants with a lint of 3 000 kg ha-1 in Xinjiang. The main results were as follows: The contents of N, P2O5, K2O in cotton leaves, stems, squares and bolls decreased obviously with the time over the whole growth duration and the falling extent was greater in high-yield cotton than in CK. Contents of N in leaves, squares and bolls, in particular in the leaves of fruit-bearing shoot was higher in high-yield cotton than in CK. Contents of P2O5 in squares and bolls and that of K2O in stems were higher in high-yield cotton than in CK during the whole growing period. The accumulations of N, P2O5 and K2O in the cotton plants could be described with a logistic curve equation. There was the fastest nutrient uptake at about 90 d for N, 92 d for P2O5 and 85 d for K2O after emergence, respectively. Total nutrient accumulation of N, P2O5 and K2O was 385.8, 244. 7 and 340.3 kg ha-1, respectively. Approximately 12. 5 kg N, 8. 0 kg P2O5 and 11.1 kg K2O were needed for producing 100 kg lint with the leaves and stems under the super high yield condition of 3 000 kg ha-1 in Xinjiang. 展开更多
关键词 XInJIAnG Cultivation of high yield COTTOn n p k Absorption dynamics Model
下载PDF
Effects of Amino Acids Replacing Nitrate on Growth,Nitrate Accumulation,and Macroelement Concentrations in Pak-choi (Brassica chinensis L.) 被引量:12
8
作者 WANG Hua-Jing WU Liang-Huan +3 位作者 WANG Min-Yan ZHU Yuan-Hong TAO Qin-Nan ZHANG Fu-Suo 《Pedosphere》 SCIE CAS CSCD 2007年第5期595-600,共6页
A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen (N... A hydroponic experiment was carried out to determine the influence of replacing 20% of nitrate-N in nutrient solutions with 20 individual amino acids on growth, nitrate accumulation, and concentrations of nitrogen (N), phosphorus (P), and potassium (K) in pak-choi (Brassica chinensis L.) shoots. When 20% of nitrate-N was replaced with arginine (Arg) compared to the full nitrate treatment, pak-choi shoot fresh and dry weights increased significantly (P ≤ 0.05), but when 20% of nitrate-N was replaced with alanine (Ala), valine (Val), leucine (Leu), isoleucine (Ile), proline (Pro), phenylalanine (Phe), methionine (Met), aspartic acid (Asp), glutamic acid (Glu), lysine (Lys), glycine (Gly), serine (Ser), threonine (Thr), cysteine (Cys), and tyrosine (Tyr), shoot fresh and dry weights decreased significantly (P ≤ 0.05). After replacing 20% of nitrate-N with asparagine (Asn) and glutamine (Gin), shoot fresh and dry weights were unaffected. Compared to the full nitrate treatment, amino acid replacement treatments, except for Cys, Gly, histidine (His), and Arg, significantly reduced (P ≤0.05) nitrate concentrations in plant shoots. Except for Cys, Leu, Pro, and Met, total N concentrations in plant tissues of the other amino acid treatments significantly increased (P ≤ 0.05). Amino acids also affected total P and K concentrations, but the effects differed depending on individual amino acids. To improve pak-choi shoot quality, Gln and Asn, due to their insignificant effects on pak-choi growth, their significant reduction in nitrate concentrations, and their increase in macroelement content in plants, may be used to partially replace nitrate-N. 展开更多
关键词 amino acids GROWTH n p and k nitrate accumulation pak-choi
下载PDF
N,P,and K characteristics of different age groups of temperate coniferous tree species in northwestern China 被引量:2
9
作者 Simin Liu Hao Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期465-472,共8页
This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the differe... This study chose dominant tree species including Picea crassifolia,Pinus armandii and Pinus tabuliformis which are distributed in Qilian Mountains,Xiaolongshan Mountains,and Bailongjiang River.According to the different tree species,ages and components,we sampled leaves,branches,stems,and roots,and measured the contents of Nitrogen,Phosphorus,Potassium,along with soil fertility.The changes of N,P,and K contents in the different tree species were studied,and the relationship between nutrient content and environmental factors was analyzed.The results indicated that the content of P in all three species was the lowest(0.039–0.28 g kg),while N content was the highest(0.095–1.72 g kg).As the terminal organ of nutrient transport,the nutrient content of leaves was the highest.P.armandii(0.45 g kg) had a higher nutrient concentration than P.tabulaeformis(0.19 g kg) and P.crassifolia(0.29 g kg).The nutrient content of each species was highest in a young forest,but lowest in a mature forest.The nutrient content of all three tree species was significantly affected by soil nutrient content,and negatively correlated with available soil nutrients. 展开更多
关键词 Different ages northwestern China n p k Tree species
下载PDF
Spatial Distribution of Soil Total Nutrients of Farmland in Liaoning Province 被引量:14
10
作者 吕国红 张玉书 +2 位作者 陈鹏狮 纪瑞鹏 焦晓光 《Agricultural Science & Technology》 CAS 2010年第1期154-158,共5页
[Objective]The aim was to reveal the spatial distribution characteristics of total nutrients in soil and provide a theoretical basis for farmland management and improvement of crop yield. [Method]GIS technique was use... [Objective]The aim was to reveal the spatial distribution characteristics of total nutrients in soil and provide a theoretical basis for farmland management and improvement of crop yield. [Method]GIS technique was used to analyze the spatial distribution characteristics of total C,total N,total P and total K for different soil layers in Liaoning Province. [Result]The results showed that the content of total C,total N,total P decrease from east to west,but the content of total K was high in north district of Liaoning Province. The content of total C,total N,total P and total K was higher in soil surface (0-20 cm) than the lower (20-40 cm). Total K varied less with soil depth,and its mean content was respectively 17.64 g/kg and 17.08 g/kg for soil surface and soil lower layer. [Conclusion]The results of the distribution of soil total nutrients in different soil layers supplied a theory basis for farmland management. 展开更多
关键词 Total C Total n Total p Total k Spatial distribution
下载PDF
Plant Biomass, Primary Production and Mineral Cycling of a Mixed Oak Forest in Linnebjer, Sweden
11
作者 Folke O. Andersson 《Open Journal of Forestry》 2014年第5期570-580,共11页
Plant biomass, primary production and mineral cycling were studied in a mixed deciduous forest (Quercus robur L., Tilia cordata L. and Corylus avellana L.) in southern Sweden. Plant biomass amount above and below grou... Plant biomass, primary production and mineral cycling were studied in a mixed deciduous forest (Quercus robur L., Tilia cordata L. and Corylus avellana L.) in southern Sweden. Plant biomass amount above and below ground was 201 and 37 t&middotha-1, respectively. Primary production above and below ground was an estimated 13.3 and 2.3 t&middotha-1, respectively. Carbon was the dominant element in the forest ecosystem, comprising 133 t&middotha-1. Other major elements were: N > Ca > K > Si > Mg > S > Mn > P > Fe and Na (range 1123 to 18 kg&middotha-1), followed by some trace elements. Yearly litterfall restored 6.0 t&middotha-1 organic matter or 2.3 t&middotha-1 carbon. Approximately 45% decomposed and returned to the soil during the year. Monitoring of other elements revealed that the ecosystem received inputs through dry and wet deposition, in particular 34.4 kg&middotha-1 S and 9.4 kg&middotha-1 of N yearly as throughfall. Determination of yearly biomass increase showed that the oak forest ecosystem was still in an aggradation or accumulation phase. 展开更多
关键词 plant BIOMASS pRIMARY production LITTERFALL DEpOSITIOn CYCLInG of C n p k S
下载PDF
The Effects of Legume Crops (Pea and Faba Bean) on Soil Nutrients Availability and Yield Parameters of Subsequent Cabbage Crops under Organic Production Conditions
12
作者 Glenda Sallaku Josif Liko +1 位作者 Zamira Rada Astrit Balliu 《Journal of Environmental Science and Engineering(A)》 2016年第12期619-625,共7页
Three equal field plots were cultivated with respectively wheat, field pea and faba bean. The common conventional production technology, including the use of chemical fertilizers was applied in wheat, but no fertilize... Three equal field plots were cultivated with respectively wheat, field pea and faba bean. The common conventional production technology, including the use of chemical fertilizers was applied in wheat, but no fertilizers at all were used in faba bean and field pea plots. Atter legume harvesting, forty day old broccoli and cauliflower seedlings were transplanted to each of them according to three replications randomized block design. The transplanting was conducted at equal planting density, and common organic production practices were applied in entire production cycle. The legume crops improved soil fertility by increasing total soil N (Nitrogen) and improving P (Phosphorus) and K (Potassium) availability to the subsequent crops. As a result, an enhanced vegetative growth, improved curd setting and increased average curd weight was found in broccoli and cauliflower. However, there were significant differences between legume crops themselves regarding the proved benefits to the subsequent crops, confirming a clear advantage of faba bean versus field pea. A significantly higher above ground biomass was recorded in cauliflower plants followed faba bean, compared with field pea and wheat, but no difference was found regarding the biomass production in broccoli. The higher percentage of plants set curds (either broccoli or cauliflower) was obtained in the variants followed faba bean and then field pea. The same was true regarding total curd yield and the average curd weight for both: broccoli and cauliflower. 展开更多
关键词 Total n nitrogen extractable p phosphorus) extractable k potassium) average curd weight curd yield.
下载PDF
Effects of Nitrogen,Phosphorus and Potassium Application on Growth and Dry Matter Accumulation in Mulberry 被引量:1
13
作者 刘刚 黄盖群 +5 位作者 殷浩 张建华 朱永群 危玲 佟万红 林超文 《Agricultural Science & Technology》 CAS 2013年第6期899-904,共6页
In this paper, the effect of different fertilizer treatments on the main indexes of growth and development and dry matter accumulation of perennial mulberry, which is cut and pruned in summer, were studied with ‘3414... In this paper, the effect of different fertilizer treatments on the main indexes of growth and development and dry matter accumulation of perennial mulberry, which is cut and pruned in summer, were studied with ‘3414’ field experiment design. The results showed that N, P, and K at proper amounts could promote mulberry growth and development, improve its dry matter content, increase its dry matter accumulation. The effects of N, P, K on leaf yield per plant were respectively expressed as follows: N2 N3 N1 N0 , P2 P1 P3 P0 , K2 K1 K3 K0 . It can be concluded that the recommended fertilizer amounts of dry matter accumulations in mulberry leaf were 694.36 kg/hm2 of N, 198.15 kg/hm2 of P, and 274.26 kg/hm2 of K and the dry matter achieved the maximum at 8 045.04 kg/hm2 . The recommended fertilizer amounts of accumulated dry matter in branch were 1 000.05 kg/hm2 of N, 242.04 kg/hm2 of P, and 218.01 kg/hm 2 of K, and the dry matter achieved the maximum at 5 969.05 kg/hm2 . The recommended fertilizer amount in young shoots were 883.76 kg/hm2 of N, 204.48 kg/hm2 of P and 426.59 kg/hm2 of K and dry matter achieved the maximum at 1 410.24 kg/hm2 . This paper could provide reference for the construction of highly-qualified mulberry field in Sichuan hilly area. 展开更多
关键词 MULBERRY n p and k Fertilization Fertilizer amount Growth and development Dry matter accumulation
下载PDF
Effect Models of Nitrogen,Phosphorus and Potassium Fertilizer Formulation in Banana 被引量:1
14
作者 匡石滋 田世尧 +3 位作者 李春雨 易干军 洪炎龙 万国富 《Agricultural Science & Technology》 CAS 2010年第9期130-135,共6页
[Objective] The aim was to modify the application amount of N,P and K fertilizer so as to provide a reference for establishing balanced fertilization index system of banana.[Method]The N,P and K fertilizer "3414" te... [Objective] The aim was to modify the application amount of N,P and K fertilizer so as to provide a reference for establishing balanced fertilization index system of banana.[Method]The N,P and K fertilizer "3414" test was carried out on banana,and then regression analysis was performed on the fertilizer effect.Ternary quadratic,binary quadric and one-variable quadratic regression equations for the fertilizer effect on the banana yield were constructed.[Result]Suitable amount of N,P and K fertilizer had significant yield improving effect,whereas overdose of fertilizer application led to decreasing of utilization rate of fertilizer.Therefore,suitable amount of N,P and K fertilizer should be selected in production.It could be concluded that one-variable quadratic regression equations was the best model to calculate the suitable fertilizer amount.The best yield range of banana in the tested field was 44.193-45.904 t/hm2,while the corresponding optimum application amount of N,P2O5 and K2O was 795.1,262.3 and 1 236.9 kg/hm2 respectively,and the ratio among nitrogen,phosphorus and potassium are 1∶0.33∶1.55.[Conclusion]The result in this study could provide references for the soil types similar to the tested field. 展开更多
关键词 BAnAnA nITROGEn phosphorus and potassium fertilization Fertilizer application model Optimum application amount
下载PDF
Spatial Differentiation of Elements in Soils on Red-Earthy Hill Landscape of Central China 被引量:1
15
作者 CHENZHI-CHENG ZHAOWEN-JUN 《Pedosphere》 SCIE CAS CSCD 1991年第2期127-136,共10页
Samples of 21 soil profiles and 165 top soils from an area of approximate 1.5km^2 on red-earthy hill landscape were collected and analysed.The content of Ca,Mg,K,P,Fe,Mn,Zn and Cu in soils relate with the kind of pare... Samples of 21 soil profiles and 165 top soils from an area of approximate 1.5km^2 on red-earthy hill landscape were collected and analysed.The content of Ca,Mg,K,P,Fe,Mn,Zn and Cu in soils relate with the kind of parent material and the position of topography,however,there is great variation due to the local difference of the form of soil utilization.From the difference in spatial distribution of elements content,it is believed that eight kinds of elements are lost by chemical leaching and physical translocation,meanwhile some are added (such as Ca,P,K,Mg) and some mobilized (such as Fe,Mn,Zn,Cu and P) through cultivation,fertilization and irrigation in the soils on the landscape investigated.The sectional differentiation in abundance or deficiency of elements in top soils on the landscape investigated is distinct,which is important for carrying out agricultural management and reasonable fertilization according to local conditions. 展开更多
关键词 contents of Ca Mg k p Fe Mn Zn and Cu geochemical behavior sectional differentiation
下载PDF
Macronutrients Uptake in Soybean as Affected by <i>Bradyrhizobium japonicum</i>Inoculation and Phosphorus (P) Supplements
16
作者 Eutropia V. Tairo Patrick A. Ndakidemi 《American Journal of Plant Sciences》 2014年第4期488-496,共9页
Field and glasshouse experiments were conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on macronutrient uptake by soybean. The treatments consisted of B. japonicum inoculation (... Field and glasshouse experiments were conducted to study the effect of B. japonicum inoculation and phosphorus supplementation on macronutrient uptake by soybean. The treatments consisted of B. japonicum inoculation (with & without), phosphorus supplementation at the levels of 0, 20, 40 and 80 kg P·ha-1. Both treatments were replicated four times in a split plot design. The macronutrients considered were N, P, K, Ca and Mg. Results showed that inoculation with B. japonicum significantly contribute to the uptake of N, P, K, Ca and Mg in roots, shoots, pods and the whole soybean plant. Likewise, phosphorus supplementation significantly enhanced the uptake of N, P, K, Ca and Mg in roots, shoots, pods and the whole plant. The use of effective strains of rhizobia and P supplementation was an effective way of enhancing the growth of soybean, eventually the uptake of macronutrients in plant organs. 展开更多
关键词 Legumes plant nutrients nitrogen (n) pHOSpHORUS (p) potassium (k) Calcium (Ca) Magnesium (Mg)
下载PDF
The Growth Characteristics of Three Terrestrial Plants Cultivated with Biogas Slurry as a Hydroponic Medium
17
作者 Qun Kang Jinhui Zhao +3 位作者 Pan Zhu Qin Gong Ling Wang Zhaohua Li 《American Journal of Plant Sciences》 2020年第6期819-831,共13页
Biogas slurry is a traditional high-quality organic liquid fertilizer. Three terrestrial plants with high economic value, fu </span><span style="font-family:Verdana;">gui</span> <span st... Biogas slurry is a traditional high-quality organic liquid fertilizer. Three terrestrial plants with high economic value, fu </span><span style="font-family:Verdana;">gui</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;">, yang </span><span style="font-family:Verdana;">xin</span> <span style="font-family:Verdana;">cai</span> <span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> strawberry, were selected for hydroponic cultivation using an optimal dilution of biogas slurry. The results of the experiments showed that strawberries could bloom and bear fruit and fu </span><span style="font-family:Verdana;">gui</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> and yang </span><span style="font-family:Verdana;">xin</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> grew well. However, in comparison with the control groups planted in soil, all three crops were subject to a certain degree of environmental stress, as shown by changes in growth, biomass indicators, physiological indicators </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> morphological indicators. The leaves and stems of yang </span><span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> and fu </span><span style="font-family:Verdana;">gui</span> <span style="font-family:Verdana;">cai</span><span style="font-family:Verdana;"> were tested for several types of heavy metals, and all met the requirements for human consumption. It is feasible to cultivate these three plants with biogas slurry. The results of this study can help guide hydroponic production practices and have practical significance and reference value. 展开更多
关键词 Biogas Slurry Fu Gui Cai Yang Xin Cai STRAWBERRY n/p/k Vitamin C CHLOROpHYLL Heavy Metals
下载PDF
藻类爆发对太湖梅梁湾水体中NPK含量的影响 被引量:37
18
作者 杨顶田 陈伟民 +2 位作者 江晶 季江 曹文熙 《应用生态学报》 CAS CSCD 2003年第6期969-972,共4页
1998~ 2 0 0 0年对太湖梅梁湾的实测结果表明 ,在一定范围内叶绿素a的含量与温度呈现明显的正相关 ;NH4+ N和总氮 (TN)、总磷 (TP)含量在每年的八九月份最低 ,总含量与叶绿素a呈正相关 ,随着叶绿素a含量上升 ,N、P含量呈现下降趋势 ;K... 1998~ 2 0 0 0年对太湖梅梁湾的实测结果表明 ,在一定范围内叶绿素a的含量与温度呈现明显的正相关 ;NH4+ N和总氮 (TN)、总磷 (TP)含量在每年的八九月份最低 ,总含量与叶绿素a呈正相关 ,随着叶绿素a含量上升 ,N、P含量呈现下降趋势 ;K的含量与N、P相似 .排污口的 0号点和 6号点的N、P含量相对于湖中心的 8号样点来说极高 ,而且P已不是限制性营养元素 ,在其它水域 ,P依然是限制性营养元素 ,表明微囊藻 (Microcystisspp .)只在TN含量为 1~ 4mg·L-1、TP在 0 .1~ 0 . 展开更多
关键词 叶绿素A n p k 微囊藻
下载PDF
N、P、K营养元素不同配比对马占相思苗期生长的影响 被引量:22
19
作者 刘水娥 张方秋 +1 位作者 陈祖旭 孟宪法 《林业科学研究》 CSCD 北大核心 2002年第2期163-168,共6页
采用N、P、K 3营养元素 5个水平配比试验 ,分析不同配比对马占相思苗期生长的影响 ;通过正交试验 ,确定马占相思苗木对各营养元素的实际需求水平。结果表明 ,P素对马占相思苗期生长影响最大 ,其次为K素 ,而N素的影响相对较小。不同水平... 采用N、P、K 3营养元素 5个水平配比试验 ,分析不同配比对马占相思苗期生长的影响 ;通过正交试验 ,确定马占相思苗木对各营养元素的实际需求水平。结果表明 ,P素对马占相思苗期生长影响最大 ,其次为K素 ,而N素的影响相对较小。不同水平的N、P、K配比对试验苗有不同的影响 ,其中 ,N∶P∶K最佳配比为 :190∶2 5∶16 0 (mg·L- 1)。 展开更多
关键词 n p k 营养元素 配比 马占相思 苗斯生长 苗期施肥
下载PDF
N、P、K肥对香根草修复土壤镉、锌污染效率的影响 被引量:12
20
作者 郑小林 朱照宇 +2 位作者 黄伟雄 梁志伟 黄妃本 《西北植物学报》 CAS CSCD 北大核心 2007年第3期560-564,共5页
通过盆栽试验研究在30 mg/kg镉(Cd)污染土壤条件下N[CO(NH2)2:100、200、300 mg/kg土]、P(P2O5:50、100、200 mg/kg土)和K(KCl:100、200、300 mg/kg土)处理对香根草修复土壤Cd和锌(Zn)污染效率的影响。结果表明:3种N处理能促进香根草地... 通过盆栽试验研究在30 mg/kg镉(Cd)污染土壤条件下N[CO(NH2)2:100、200、300 mg/kg土]、P(P2O5:50、100、200 mg/kg土)和K(KCl:100、200、300 mg/kg土)处理对香根草修复土壤Cd和锌(Zn)污染效率的影响。结果表明:3种N处理能促进香根草地上部生长,而且显著提高地上部特别是叶的Cd和Zn含量,导致其修复效率成倍显著增加;200 mg/kg K处理显著提高Zn修复效率,但300 mg/kg K和50、200 mg/kg P处理却显著降低Cd、Zn修复效率。因此,为改善香根草对较贫瘠土壤中Cd、Zn污染的修复效率,应对香根草适施N肥,并控制或者不施P、K肥为佳。 展开更多
关键词 香根草 n p k CD Zn 修复效率
下载PDF
上一页 1 2 58 下一页 到第
使用帮助 返回顶部