Hydrocarbon accumulation and orderly distribution of whole petroleum system in marine carbonate rocks of Sichuan Basin,SW China

Based on the situation and progress of marine oil/gas exploration in the Sichuan Basin,SW China,the whole petroleum system is divided for marine carbonate rocks of the basin according to the combinations of hydrocarbon accumulation elements,especially the source rock.The hydrocarbon accumulation characteristics of each whole petroleum system are analyzed,the patterns of integrated conventional and unconventional hydrocarbon accumulation are summarized,and the favorable exploration targets are proposed.Under the control of multiple extensional-convergent tectonic cycles,the marine carbonate rocks of the Sichuan Basin contain three sets of regional source rocks and three sets of regional cap rocks,and can be divided into the Cambrian,Silurian and Permian whole petroleum systems.These whole petroleum systems present mainly independent hydrocarbon accumulation,containing natural gas of affinity individually.Locally,large fault zones run through multiple whole petroleum systems,forming a fault-controlled complex whole petroleum system.The hydrocarbon accumulation sequence of continental shelf facies shale gas accumulation,marginal platform facies-controlled gas reservoirs,and intra-platform fault-and facies-controlled gas reservoirs is common in the whole petroleum system,with a stereoscopic accumulation and orderly distribution pattern.High-quality source rock is fundamental to the formation of large gas fields,and natural gas in a whole petroleum system is generally enriched near and within the source rocks.The development and maintenance of large-scale reservoirs are essential for natural gas enrichment,multiple sources,oil and gas transformation,and dynamic adjustment are the characteristics of marine petroleum accumulation,and good preservation conditions are critical to natural gas accumulation.Large-scale marginal-platform reef-bank facies zones,deep shale gas,and large-scale lithological complexes related to source-connected faults are future marine hydrocarbon exploration targets in the Sichuan Basin.

Absorption,Accumulation and Distribution of Zinc in Highly-Yielding Winter Wheat

Zinc（Zn） is an important essential microelement for wheat.In order to study the characteristics of Zn absorption,accumulation and distribution in highly-yielding winter wheat（with a grain yield of 9 000 kg ha-1）,field experiments were conducted in Gaocheng County of Hebei Province,China.Four winter wheat cultivars,i.e.,Shimai 14,Jifeng 703,Shimai 12,and Shixin 828,and four cultivars,i.e.,Temai 1,Shimai 12,Shixin 531,and Shixin 828,were used in the experiment,during 2004-2005 and 2005-2006,respectively.Plant samples were taken from the plots at each growing stage for Zn concentration analysis.The main results showed that the concentration of Zn in various above-ground organs of wheat was 9.5-112.5 mg kg-1 at different growing stages.The organ with the highest Zn concentration differed with the change of growth center at different growing stages.Accumulation of Zn in leaf blades was the highest among all the organs during early growing period,and more than 50% of the Zn accumulation was distributed to leaf blades before jointing,and higher than that to other organs.In late growing period,however,the accumulation of Zn in grains was the highest,and 58.1% of the Zn accumulation was distributed in grains at maturity.The total accumulation of Zn in wheat plant during its life span ranged from 384.9 to 475.9 g ha-1.The amount of Zn required for the formation of 100 kg grain yield ranged from 4.3 to 5.2 g.All the organs were ordered in such a sequence that leaf blades 〉 spikes 〉 leaf sheaths 〉 stems according to their net absorption and transportation of Zn as well as their contribution to Zn accumulation in grains.58.2-60.3% of the Zn accumulated in grains was redistributed from other organs,mostly from leaf blades.Concentration and accumulation of Zn in all the organs of wheat was high during early and middle growing periods,while accumulation of Zn in grains during late growing period mainly depended on the redistribution from other organs.According to these characteristics of Zn absorption and accumulation,Zn should be applied as seed dressing or basal fertilizer,so as to accelerate the early growth and Zn absorption of wheat.

Distribution and Accumulation of Neodymium and Its Effect on Secretion of Progesterone in Mice

Distribution and accumulation of Nd, and its effect on secretion of progesterone in mice were studied using radioisotope tracer ((()^(147)Nd)) technique. Following single intraperitoneal administration of neodymium traced with (()^(147)Nd) at a dose of 200 mg·kg^(-1), uneven distribution of the radioactive Nd occurred in various tissues and organs. Much amount of (()^(147)Nd) accumulates in the bone, and the residue increases with the lapse of time. Some amount of radioactivity was also detected in eyes, blood and brain, but the accumulation decreased with the time due to excretion and re-distribution in mice. In comparison with controls, concentration of progesterone is found to be significantly lower in the serum of administered mice, indicating a significantly inhibitory effect of Nd on secretion of progesterone.

Distribution Characteristics and Accumulation Model for the Coal-formed Gas Generated from Permo-Carboniferous Coal Measures in Bohai Bay Basin, China: A Review

Coal-formed gas generated from the Permo-Carboniferous coal measures has become one of the most important targets for deep hydrocarbon exploration in the Bohai Bay Basin,offshore eastern China.However,the proven gas reserves from this source rock remain low to date,and the distribution characteristics and accumulation model for the coal-formed gas are not clear.Here we review the coal-formed gas deposits formed from the Permo-Carboniferous coal measures in the Bohai Bay Basin.The accumulations are scattered,and dominated by middle-small sized gas fields,of which the proven reserves ranging from 0.002 to 149.4×108 m3 with an average of 44.30×108 m3 and a mid-point of 8.16×108 m3.The commercially valuable gas fields are mainly found in the central and southern parts of the basin.Vertically,the coal-formed gas is accumulated at multiple stratigraphic levels from Paleogene to Archaeozoic,among which the Paleogene and PermoCarboniferous are the main reservoir strata.According to the transporting pathway,filling mechanism and the relationship between source rocks and reservoir,the coal-formed gas accumulation model can be defined into three types:"Upward migrated,fault transported gas"accumulation model,"Laterally migrated,sandbody transported gas"accumulation model,and"Downward migrated,sub-source,fracture transported gas"accumulation model.Source rock distribution,thermal evolution and hydrocarbon generation capacity are the fundamental controlling factors for the macro distribution and enrichment of the coal-formed gas.The fault activity and the configuration of fault and caprock control the vertical enrichment pattern.

Nutrient Accumulation and Distribution of Mature Pinus massoniana Plantation in Northwestern Guangxi

[Objectives]This study was conducted to reveal the characteristics of nutrient absorption and accumulation in Pinus massoniana plantations in Northwestern Guangxi.[Methods]Based on field investigation and indoor analysis,the contents,accumulation and annual net accumulation of five nutrient elements(N,P,K,Ca and Mg)in a mature P.massoniana plantation(26-year-old)in Nandan County,Guangxi Province were studied.[Results]The contents of nutrient elements in different organs of the mature P.massoniana plantation were the highest in the leaves,followed by the bark,branch and root,and the lowest in the stem.In general,among the contents of the five elements in different organs,N content was the highest,followed by K or Ca,and P and Mg were the lowest.The total accumulation of nutrient elements in the 26-year-old mature P.massoniana plantation in northwestern Guangxi was 1 384.05 kg/hm^2.Among the different structural levels of the stand,the tree layer had the highest accumulation of nutrient elements,which was 1 198.41 kg/hm^2,accounting for 86.59%of the total accumulation of nutrients in the plantation,and the accumulation of nutrients in other layers from the largest to the smallest was the litter layer(91.97 kg/hm^2),herb layer(49.86 kg/hm^2)and shrub layer(43.92 kg/hm^2),accounting for 3.17%,3.60%and 6.64%of the total nutrient accumulation of the plantation,respectively.The annual net accumulation of nutrient elements in the tree layer of the mature P.massoniana plantation was 46.09 kg/(hm^2·a),and the order of the annual net accumulation of different nutrient elements followed N>K>Ca>Mg>P;and the accumulation of 1 t of dry matter needed 6.37 kg of the five nutrients.[Conclusions]This study provides a scientific basis for the rational management of P.massoniana plantations,especially forest soil management.

Pb uptake, accumulation, subcellular distribution in a Pb－accumulating ecotype of Sedum alfredii （Hance）

Lead concentrations in roots, stems and leaves of accumulating and non accumulating ecotypes of Sedum alfredii (Hance) were studied through a hydroponic experiment with different Pb concentrations supplied as Pb(NO 3) 2. Lead concentrations in leaves and stems of the accumulating ecotype were 4-9 times and 3-5 times those of the non accumulating ecotype, and Pb accumulated amounts in stems and leaves of the accumulating ecotype were 4-9 times and 8-11 times higher than those of the non accumulating ecotype, respectively. The results indicated that the accumulating ecotype had better ability to transport Pb from roots to shoots. The subcellular distributions of Pb in the root, stem and leaf tissues were studied using sucrose differential centrifugation. Approximately 50% of Pb contents was found to be associated with the cell wall fraction in stems of the accumulating ecotype and the percentage increased to 80% both in roots and leaves, no matter when plants were grown with different levels of Pb. The results indicated that the distribution of Pb on cell walls of the accumulating ecotype could mainly account for the high tolerance to Pb.

Dynamic Simulating to the Accumulation and Distribution of Dry Matter for Black Walnut(Juglans hindsii) Seedlings

It is very important to study eco-physiological processes of plants and to determine quantitative relations between accumulation, distribution of dry matter and environmental factors for regionalization, standardization and precision agriculture. Meanwhile, global changes, e.g., atmospheric CO2 concentration rising, global warming, and climate abnormity, have been effecting on agricultural productivity. This study provides a theoretical basis for predicting productive potentials and development trends in different agricultural regions. One-year-old black walnut （Juglans hindsii） seedlings were employed as subjects for setting up the dynamic models of dry matter accumulation and distribution, based on mechanistic models of photosynthesis, matter conservation and concentration gradient. Under optimum conditions of soil moisture and mineral nutrient, during the period of the canopy construction, the dry matter accumulation of the canopy conformed to logistic curves; but the accumulation of both total biornass and dry matter of stem-root could be divided into two phases： the first phase was exponential increase, the second was linear increase. The total biomass, dry matter of canopy and stem-root all presented a fluctuant increase, which was affected by the environmental factors. Ratio of daily increase of dry matter in the canopy and the steem-root （dWJdWs） was changeable along with growth periods and environmental factors. At the initial stage of the canopy forming, dW/dWs was larger, about 3.2 on average, which indicated that the photosynthetic product was mainly used to develop leaves; in the midterm, it was about 1.9, which indicated that the distribution of dry matter in the canopy and in the stem-root was relatively balanced; when the plant tended to stop growing, dWl/dWs decreased linearly, and the main distribution of dry matter moved to the roots.

Orderliness of Hydrocarbon Accumulation Distribution in Rift Basins of Eastern China

The Cenozoic rift basins in eastern China show a clear temporal and spatial zonation and episodic tectonic evolution, which control their episodic hydrocarbon generation and zonal accumulation. In this paper, based on the study of depositional architecture, hydrocarbon migration system and dynamic evolution in the rift basins, combinations of hydrocarbon accumulation elements were analyzed using sequence stratigraphy. Hydrocarbon distribution in system tracts with different sequence orders was further studied. And we summarized stacking patterns and horizontal combination relationships for different types of reservoirs, such as lithological, tectonic-lithological, tectonic and stratigraphical reservoirs which can be observed from depression center to basin margin. The result reveals that various scales of pools exhibit significant distribution and evolution orderliness in different pool-forming units, i.e., depositional systems, plays and depressions. The regular distribution of various scales of pools is closely related to tectonic evolution and depositional filling in the rift basins. The result can be applied to the fine petroleum exploration in rift basins in eastern China. It will promote the scientific prediction and evaluation of reservoir types and their spatial distribution, lead to the active shifts of exploration targets in different zones, and thus support the stable progress of fine exploration in mature exploration areas.

Source-Contacting Gas: Accumulation Mechanism and Distribution in China

Source-contacting gas, which is also called basin-center gas, deep basin gas, is the tight-sand gas accumulation contacting closely to its source rocks. Having different accumulation mechanisms from conventional gas reservoirs that are formed by replacement way, the typical source-contacting gas reservoirs are formed by piston-typed migration forward way. Source-contacting gas accumulations exhibit a series of distinctly mechanic characteristics. According to the valid combination of these characteristics, the estimation for the type of discovered gas reservoirs or distributions of source-contacting gas reservoirs can be forecasted. The source-contacting gas is special for having no edge water or bottom water for gas and complicated gas-water relationships, which emphasizes the intimate association of reservoir rocks with source rocks, which is called the root of the gas reservoir. There are many basins having the mechanic conditions for source-contacting gas accumulations in China, which can be divided into three regions. Most of the basins with favorable accumulation conditions are located mainly in the central and western China. According to the present data, basins having source-contacting gas accumulations in China can be divided into three types, accumulation conditions and configuration relationships are the best in type A basins and they are the larger basins in central China. Type B basins with plain accumulation conditions exist primarily in eastern China and also the basins in western China. Accumulation conditions and exploration futures are worse in type C basins, which refer mainly to the small basins in southern China and China Sea basins. Main source-contacting gas basins in China are thoroughly discussed in this paper and the distribution patterns of source-contacting gas in five huge basins are discussed and forecasted.

Accumulation and Distribution Dynamics of Soluble Carbohydrate in Helianthus tuberosus under Drought Stress

With Qingyu 1 and Qingyu 2 as test materials, variation of soluble carbohydrate content in different parts were studied under two types of artificially simulated drought stress （polyethylene glycd PEG-6000 stress and water-controlling stress）. The results showed that under the stress of PEG, soluble carbohydrate content in leaves of Qingyu 1 and Qingyu 2 increased with the prolonging time of stress; soluble carbohydrate content in stems of Qingyu 1 did not show regular changes with the prolonging time of stress, while 30% PEG stress received the best effect on Qingyu 2 after 24 h; soluble carbohydrate content in roots of Qingyu 1 and Qingyu 2 increased with the prolonging time of stress. Under different intensities of water-controUing stress, soluble carbohydrate content in leaves of Qingyu 1 first increased then decreased, while that in leaves of Qingyu 2 increased; soluble carbohydrate content in stems of Qingyu 1 and Qingyu 2 increased with the pro- longing time of water-controlling stress; soluble carbohydrate content in roots of Qingyu 1 decreased with the prolonging time of water-contmlling stress, while that in roots of Qingyu 2 differed slightly.

An improved model of partition curve based on accumulation normal distribution function

Extensive studies based on partition curve of gravity separation have been investigated. All created models are merely used to simulate density distribution at the same size fraction. However, they cannot be used to predictive distribution of materials depending on compound feature of density and size. According to this situation, an improved model of partition curve based on accumulation normal distribution, which was distinguished from conventional model of accumulation normal distribution for partition curve, was proposed in this paper. It could simulate density distribution at different size fractions by using the density-size compound index and conflating the partition curves at different size fractions as one partition curve. The feasibility of three compound indexes, including mass index, settlement index and transformation index, were investigated. Specific forms of the improved model were also proposed. It is found that transformation index leads to the best fitting results, while the fitting error is only 1.75 according to the fitting partition curve.

Distribution and accumulation of heavy metals in Avicennia marina community in Shenzhen,China

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Review Study on the Accumulation and Release of Trace Metal Elements on Aluminum Containing Sediments in Drinking Water Distribution System

Accumulation and releasing of trace metal elements on aluminum containing sediments of inner drinking water pipe is discussed,as studied from five variations effecting:raw water quality,chemical reagents,solution pH and drinking water flow condition.In order to decrease the release of trace metal elements,and to ensure the pipe operation and human safety,water quality adjustment is suggested to avoid aluminum containing sediments formation in drinking distribution system.The maximum amounts of accumulation of common trace metal elements are given.Future trends of development in this field are also proposed.

Accumulation model and prediction of Miocene heavy oil distribution in Gulf of Suez Basin,Egypt

The Gulf of Suez Basin is a very mature and extremely prospective petroleum province. Many heavy oil fields have been found in the Basin,and such reserves are abundant. Characteristics and models of heavy oil are analyzed in this study based on tectonic,basin evolution,stratigraphic distribution and geochemical data.The best reservoirs of heavy oil are Miocene sandstone and limestone formations. Source rocks of hydrocarbon include deep limestone and shale of the Brown Limestone,the Thebes Formation and the Rudeis Formation.Thick evaporite rocks with rock salts and anhydrites deposited broadly throughout the basin are the most important regional seals,whereas Miocene shales are intraformational and regional seals that cover small areas. Heavy oil could be directly generated or densified during vertical migration along faults and reservoir accumulation.The heavy oil accumulation model is a mixed model that includes three mechanisms: fault dispersal,sulfocompound reactions and hydrocarbons generated from immature source rock. After analyzing the model and the distribution of source rocks,reservoirs,heavy oil fields and structures,it is concluded that the potential heavy oil area is at the center of the basin.

Effects of soil potassium levels on dry matter and nutrient accumulation and distribution in cotton

Background Potassium(K)is an essential nutrient for plant growth and development.However,plant fertilization ignoring the soil K level is very likely to cause excessive fertilizer use,and further arouse a series of side effects.This study investigated the response of cotton growth to different soil K levels and the uptake of major nutrients,aiming to evaluate the appropriate K supply level for cotton growth.Using a random block design with 6 soil K levels,we conducted 18 micro-zones field experiments over two continuous years.The soil available K concentration of each treatment was K1(99.77-100.90 mg·kg^(-1)),K2(110.90-111.26 mg·kg^(-1)),K3(123.48-128.88 mg·kg^(-1)),K4(140.13-145.10 mg·kg^(-1)),K5(154.43-155.38 mg·kg^(-1)),and K6(165.77-168.75 mg·kg^(-1)).Cotton nutrient contents,soil nutrient contents,accumulation and distribution of dry matter in cotton were determined,and the relationships between K content in soil and plants and dry matter accumulation were analyzed.Results The soil K content had a significantly positive relationship with dry matter and K accumulation in cotton plants.There were significant differences in dry matter accumulation,single-plant seed cotton yield,mineral nutrient uptake and the proportion of K accumulation in reproductive organs among different soil K levels.The results showed that there was significant difference between K4 and lower K level treatments(K1 and K2),but no significant difference between K4 and higher K level treatments(K5 and K6)in dry matter,single-plant seed cotton yield,or accumulation,distribution and seed cotton production efficiency of N,P and K.Conclusion The soil K level of K4 was able to provide sufficient K for cotton growth in our experiment.Therefore,when the soil K level reached 140.13 mg·kg^(-1),further increasing the soil K concentration no longer had a significant positive effect on cotton growth.

Nutrient Accumulation and Distribution in Cotton Promoted by Removal of Mulch Film

Plastic film mulching affects changes in nutrient contents in soil and absorption and utilization of nutrients in plants were by changing hydrothermal condition of soil.The temporal and spatial variation of the total soil salt and nutrient contents with mulch film removed at three different times during the early cotton growth stage and its effects on nutrient absorption and accumulation in cotton plants were studied over 2015-2017.The film removal treatments reduced salt accumulation in normal rainfall year(2017).Film removal increased contents of soil organic matter,the total phosphorus and available potassium at the end of growth stage,increased contents of soil hydrolyzable nitrogen and the total nitrogen in the surface soil layer(0-10 cm),and increased the total nitrogen contents in the deep soil layer(40-50 cm).Film removal increased accumulation of nitrogen and phosphorus nutrients in cotton plants in 2017 and accumulation of nitrogen,phosphorus and potassium nutrients in cotton plants in heavy rainfall year(2016).These experimental results indicated that removal of mulch film at an appropriate and targeted time in the bud stage of cotton promoted nutrient absorption.

Distribution and their pollution assessment of heavy metals in the sediments of the Yalu River Estuary and its adjacent coastal waters

The present paper deals with the distribution patterns of heavy metals and the associated influenc- ing factors in the Yalu River Estuary and its adjacent coastal waters. Based upon the analysis of the surficial and core sediments measurements, the pollution of heavy metal and potentiM ecological risk were evaluated. The burial flux and contents of heavy metals （except for copper） have been continuously increasing since the 1920s. Therefore, the gross potential ecological risk for the sedi- ments was high or very high, and the study area was endangered by heavy metals contamination. Heavy metals originated mainly from upstream pollutant input, correlation analysis showed that chromium, nickel, zinc~ cadmium, lead, arsenic, and mercury in the sediments of the middle and west channels as well as the sea area of the western Yalu River Estuary concentrations were most probably derived from similar sources. In contrast, the metal of copper most probably originated from sources different from the other metals. Preliminary studies indicate that copper contamina- tion was most likely the result of emission from mining activities situated at the upstream of the river. The contents of heavy metals in the sediments of estuarine turbidity maximum zone of Yalu River were larger than those of any other areas in the middle channel. With large portion of fine sediments, weaker hydrodynamics, and richer sources of heavy metals, the sediments of the west channel, were even more enriched with heavy metals than those of the middle channel.

Genetic types and distribution of shallow-buried natural gases

Great volumes of shallow-buried （〈2,000 m） natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs in China are characterized by coexistence of biogas and low-mature gas, so identifying the genetic types of shallow gases is important for exploration and development in sedimentary basins. In this paper, we study the gas geochemistry characteristics and distribution in different basins, and classify the shallow gas into two genetic types, biogas and low-mature gas. The biogases are subdivided further into two subtypes by their sources, the source rock-derived biogas and hydrocarbon-derived biogas. Based on the burial history of the source rocks, the source rock-derived biogases are divided into primary and secondary biogas. The former is generated from the source rocks in the primary burial stage, and the latter is from uplifted source rocks or those in a secondary burial stage. In addition, the identifying parameters of each type of shallow gas are given. Based on the analysis above, the distributions of each type of shallow gas are studied. The primary biogases generated from source rocks are mostly distributed in Quaternary basins or modem deltas. Most of them migrate in watersoluble or diffused mode, and their migration distance is short. Reservoir and caprock assemblages play an important role in primary biogas accumulation. The secondary biogases are distributed in a basin with secondary burial history. The oil-degraded biogases are distributed near heavy oil pools. The low-mature gases are widely distributed in shallow-buried reservoirs in the Meso-Cenozoic basins.

On the Paleogene coal-measure distribution over the China sea area

The Paleogene coal accumulation basins of China are part of the global Tertiary coal-accumulated zone of the Pacific Rim located in the eastern coastal provinces and areas. Although the coal-bearing basins of the China Sea area are faults and depressed basins, they come up in groups. The overall structures are suitable for the development of coal-bearing deposition. The continuity of basin groups are good, and the coal-bearing depositions are thick. For example, the coal-bearing deposi- tion is more than a kilometer thick at the Qiongdongnan Basin and Xihu Sag in the East China Sea, which the continental Pa- leogene coal basins cannot reach. Research shows that the coal accumulation basins in the sea area consist of many sags. There are two types of coal accumulation sags： half-graben sag and graben sag. In terms of water depth, coal accumulation sags can also be classified as deep-water half-graben sag and shallow-water half-graben sag; the graben sag is the deep-water sag. There are two distinct coal-accumulated zones in the basin： gentle slope and steep slope, with the gentle slope being the dominant one. The marshes of the supratidal zone and intertidal zone in a tidal flat system is favorable for the coal accumulation process widely taking place. There are two types of peat accumulation： autochthonous accumulation and allochthonous accumulation. Because of tectonic activities in the basins, allochthonous accumulations may be the more important form of coal-forming ac- tivities in the sea area. The very thick coal-bearing deposition in the sea area provides a rich material base for the assemblage of coal-related gas. Also, as a result of the deep burial depth, the degree of coal metamorphism is relatively high, so the coal-bearing strata become good hydrocarbon source rocks.

Effect of Alternate Bearing Phenomenon and Boron Foliar Application on Nitrogen-15 Uptake,Translocation and Distribution in Mango Tree(cv.Zebda)

The objectives of this investigation are to study nitrogen uptake,translocation,accumulation and distribution in mango tree organs using labeled nitrogen(^(15)N)and to understand the mechanism of boron action in increasing fruit yield in the off-year.A field experiment was conducted using fifteen-year-old mango trees(cv.Zebda)grown at Al Malak Valley Farm,El-Sharkeya Governorate-Egypt.Treatments included the application of(^(15)NH4)2SO4,“in the on-year”,at a rate of 50 g nitrogen/tree through the stem injection technique.While boron was sprayed on the same trees“in the off-year”at the following rates:0.0(control),250 and 500 mg·L^(-1).The authors hypothesize that boron and nitrogen act synergistically to increase mango fruit yield in the off-year.Results indicated that the highest ^(15)N uptake and accumulation in the on and off-years was observed in the upper(young leaves).When boron was applied at 250 mg·L^(-1),in the off-year,the upper(young leaves)recorded the highest ^(15)N uptake and accumulation(%^(15)Ndff=13.93)relative to the other two leaf categories and those of the on-year.In the on-year fruit accumulated higher ^(15)N than leaf or bud.In the off-year,bud exhibited the highest ^(15)N accumulation without boron application,while leaves exhibited the highest ^(15)N with boron application.The highest%^(15)Ndff in all tree organs was observed at 250 mg·L^(-1) boron rate.Boron increased nitrogen uptake,translocation and accumulation in mango tree organs.A synergistic relationship was observed between boron and nitrogen which led to an increase in fruit yield in the off-year.