Significant Nutritional Gaps in Tibetan Adults Living in Agricultural Counties Along Yarlung Zangbo River.

Background: Dietary intake and nutritional assessing data from a representative sample of adult population living in an agricultural zone on Tibet Plateau are still lacking nowadays. This study aimed to assess the daily dietary intakes and respective food sources in 552 local residents (≥ 18 years old, 277 men and 275 women) living in 14 agricultural counties along the Yarlung Zangbo River on Tibet Plateau.

Methods: Food consumption data were collected using a validated cultural-specific food frequency questionnaire that contained all local Tibetan foods and analyzed with three fixed factors: gender, age, and region.

Fertilizer and pesticide reduction in cherry tomato production to achieve multiple environmental benefits in Guangxi, China.

Cherry tomatoes, as a highly profitable vegetable, consume a substantial amount of fertilizer and pesticide compared with other staple crops, which leads to remarkably negative environmental impacts. The optimization of these agricultural inputs to mitigate these environmental burdens and improve cherry tomato yield has drawn little attention. This study used life cycle assessment (LCA) combined with a field investigation to analyze the environmental benefits under optimized fertilizer and pesticide inputs (i.

Harvesting more grain zinc of wheat for human health.

Increasing grain zinc (Zn) concentration of cereals for minimizing Zn malnutrition in two billion people represents an important global humanitarian challenge. Grain Zn in field-grown wheat at the global scale ranges from 20.4 to 30.

[Reactive nitrogen loss pathways and their effective factors in paddy field in southern China].

Based on the literature data, the N20 emission, N leaching, N runoff and NH3 volatilization were compared from different rice production regions and their effective factors were evaluated. The results showed that N2 0 emission, N leaching and N runoff in single rice in Yangtze River basin were higher than in other rice production regions, with N loss of 1.89, 6.

Intercropping enhances soil carbon and nitrogen.

Intercropping, the simultaneous cultivation of multiple crop species in a single field, increases aboveground productivity due to species complementarity. We hypothesized that intercrops may have greater belowground productivity than sole crops, and sequester more soil carbon over time due to greater input of root litter. Here, we demonstrate a divergence in soil organic carbon (C) and nitrogen (N) content over 7 years in a field experiment that compared rotational strip intercrop systems and ordinary crop rotations.

Plant diversity and overyielding: insights from belowground facilitation of intercropping in agriculture.

Despite increasing evidence that plant diversity in experimental systems may enhance ecosystem productivity, the mechanisms causing this overyielding remain debated. Here, we review studies of overyielding observed in agricultural intercropping systems, and show that a potentially important mechanism underlying such facilitation is the ability of some crop species to chemically mobilize otherwise-unavailable forms of one or more limiting soil nutrients such as phosphorus (P) and micronutrients (iron (Fe), zinc (Zn) and manganese (Mn)). Phosphorus-mobilizing crop species improve P nutrition for themselves and neighboring non-P-mobilizing species by releasing acid phosphatases, protons and/or carboxylates into the rhizosphere which increases the concentration of soluble inorganic P in soil.

New technologies reduce greenhouse gas emissions from nitrogenous fertilizer in China.

Synthetic nitrogen (N) fertilizer has played a key role in enhancing food production and keeping half of the world's population adequately fed. However, decades of N fertilizer overuse in many parts of the world have contributed to soil, water, and air pollution; reducing excessive N losses and emissions is a central environmental challenge in the 21st century. China's participation is essential to global efforts in reducing N-related greenhouse gas (GHG) emissions because China is the largest producer and consumer of fertilizer N.

Greenhouse gas emissions from a wheat-maize double cropping system with different nitrogen fertilization regimes.

Here, we report on a two-years field experiment aimed at the quantification of the emissions of nitrous oxide (N2O) and methane (CH4) from the dominant wheat-maize double cropping system in North China Plain. The experiment had 6 different fertilization strategies, including a control treatment, recommended fertilization, with and without straw and manure applications, and nitrification inhibitor and slow release urea. Application of N fertilizer slightly decreased CH4 uptake by soil.

Characterization of root response to phosphorus supply from morphology to gene analysis in field-grown wheat.

The adaptations of root morphology, physiology, and biochemistry to phosphorus supply have been characterized intensively. However, characterizing these adaptations at molecular level is largely neglected under field conditions. Here, two consecutive field experiments were carried out to investigate the agronomic traits and root traits of wheat (Triticum aestivum L.

Genotypic differences in zinc efficiency of Chinese maize evaluated in a pot experiment.

Background: Zinc (Zn) deficiency, a major problem limiting crop production worldwide, is common on calcareous soils of China. Using such a Zn-deficient soil supplied adequately with plant mineral nutrients, with or without Zn, 30 Chinese maize genotypes were grown for 30 days in a greenhouse pot experiment and assessed for Zn efficiency (ZE), measured as relative biomass under Zn-limiting compared with non-limiting conditions.

Results: Substantial variation in tolerance to low Zn nutritional status was observed within the maize genotypes.

Root growth in response to nitrogen supply in Chinese maize hybrids released between 1973 and 2009.

Root growth has a fundamental role in nitrogen (N) use efficiency. Nevertheless, little is known about how modern breeding progress has affected root growth and its responses to N supply. The root and shoot growth of a core set of 11 representative Chinese maize (Zea mays L.

Integrated soil-crop system management for food security.

China and other rapidly developing economies face the dual challenge of substantially increasing yields of cereal grains while at the same time reducing the very substantial environmental impacts of intensive agriculture. We used a model-driven integrated soil-crop system management approach to develop a maize production system that achieved mean maize yields of 13.0 t ha(-1) on 66 on-farm experimental plots--nearly twice the yield of current farmers' practices--with no increase in N fertilizer use.

[Study on the response of middle and trace elements in Humulus scandens leaves to atmospheric reactive nitrogen with ICP-AES].

Based on field measurements, the effects of atmospheric reactive nitrogen (ARN) on the middle/trace element concentrations in the leaves of wild plant humulus scandens were analyzed. Leaves of H. scandens were collected from six sites around Beijing in the North China Plain, and the concentrations of Ca, Mg, S, Fe, Mn, Cu, Zn, B, and Na in the leaves were determined with inductively coupled plasma atomic emission spectrometry (ICP-AES).

Localized application of soil organic matter shifts distribution of cluster roots of white lupin in the soil profile due to localized release of phosphorus.

Background And Aims: Phosphorus (P) is a major factor controlling cluster-root formation. Cluster-root proliferation tends to concentrate in organic matter (OM)-rich surface-soil layers, but the nature of this response of cluster-root formation to OM is not clear. Cluster-root proliferation in response to localized application of OM was characterized in Lupinus albus (white lupin) grown in stratified soil columns to test if the stimulating effect of OM on cluster-root formation was due to (a) P release from breakdown of OM; (b) a decrease in soil density; or (c) effects of micro-organisms other than releasing P from OM.

[Nitrogen status diagnosis of rice by using a digital camera].

In the present research, a field experiment with different N application rate was conducted to study the possibility of using visible band color analysis methods to monitor the N status of rice canopy. The Correlations of visible spectrum band color intensity between rice canopy image acquired from a digital camera and conventional nitrogen status diagnosis parameters of leaf SPAD chlorophyll meter readings, total N content, upland biomass and N uptake were studied. The results showed that the red color intensity (R), green color intensity (G) and normalized redness intensity (NRI) have significant inverse linear correlations with the conventional N diagnosis parameters of SPAD readings, total N content, upland biomass and total N uptake.

[Influence of interpolation method and sampling number on spatial prediction accuracy of soil Olsen-P].

Different from the large scale farm management in Europe and America, the scattered farmland management in China made the spatial variability of soil nutrients at county scale in this country more challenging. Taking soil Olsen-P in Wuhu County as an example, the influence of interpolation method and sampling number on the spatial prediction accuracy of soil nutrients was evaluated systematically. The results showed that local polynomial method, ordinary kriging, simple kriging, and disjunctive kriging had higher spatial prediction accuracy than the other interpolation methods.

[Application of ICP-AES to detecting nutrients in grain of wheat core collection of China].

Deficiency of micronutrients, especially iron and zinc, has been a serious malnutrition problem worldwide in human health. Increasing Fe and Zn concentrations in grains by means of plant breeding is a sustainable, effective and important way to improve human mineral nutrition and health. However, little information on grain Fe and Zn concentrations in Chinese wheat genotypes is available.

[The content of nutrient elements of plant in KCl fertilizer].

Potassium is one of the three most important plant nutrient elements, so many researchers pay attention on its fertilizer efficiency. But fertilizers were all industrial products containing many other nutrient elements in most experiments of fertilizer efficiency. All the other nutrient elements, including necessitous elements and beneficial elements in potassium fertilizer (KCl) were analyzed by method of ICP-MS.

[Contents of nutrient elements in NH4(+)-N fertilizer and urea].

Fertilizer contains not only one compound or one element, so it is important to determine the contents of other elements necessitous and beneficial to plant. All the other nutrient elements for plant, including necessitous elements and beneficial elements in ammonia nitrogen fertilizer ((NH4)2SO4) and CO(NH2)2, were analyzed by method of ICP-MS. The results showed that ammonia nitrogen fertilizer ((NH4)2SO4) and CO(NH2)2 both contain many necessitous elements, Mg, P, K, Ca, Mn, Fe, Ni, Cu, Zn and Mo, thereinto the contents of Mg, P, K, Ca, Mn and Fe were on microg x g(-1) the level, and Ni, Cu, Zn and Mo were on the ng x g(-1) level; compared with CO(NH2)2, ammonia nitrogen fertilizer ((NH4)2SO4) contains more necessitous elements and beneficial elements except Mo and Si.

[Distribution of six trace elements in Fuji apple].

Trace elements are important nutritional elements for human health. Six trace elements in Fuji apple skin and pulp were analyzed by the method of ICP-MS. The results showed that the concentrations of Ca, Mn, Fe, Se, Mo and I were 197 910, 1 623, 14 400, 2, 47 and 91 ng x g(-1) x FW in apple skin respectively; and 58 360, 281, 550, 4, 18 and 24 ng x g(-1) x FW respectively in apple pulp.

[Nitrogen status diagnosis of summer maize by using visible spectral analysis technology].

In the present paper, a field experiment with different N rates was conducted to study the possibility of using the visible spectrum of crop canopy to diagnose N status for the summer maize. Visible spectrum parameters were compared with the leaf SPAD readings, total N concentration and vein nitrate concentration. Field measurement data showed that the greenness intensity, blueness intensity, normalized redness intensity, normalized greenness intensity and normalized blueness intensity of the maize canopy have significant relationships with leaf SPAD readings, total N concentration and vein nitrate concentration (under a low N input condition, with vein nitrate concentration < 2 000 mg x L(-1)) at summer maize 10 leaves unfold stage.

[Effects of forms and level of nitrogen fertilizer on the content of chlorophyll in leaves of maize seedling].

The level and form of nitrogen fertilizer could significantly influence the growth and development of plant. The present paper studied the content of chlorophyll by the instrument SPAD-502 after treated with different nitrogen fertilizer level and different nitrogen fertilizer form. The results showed that the contents of chlorophyll in the last expanding leaf of maize seedling treated by levels of 0, 100 and 200 kgN x hm(-2) respectively had no significant difference, with the value of SPAD ranging from 43.

[Determination of major elements in superphosphate by X-ray fluorescence spectrometry].

Phosphate fertilizer is one of the most important fertilizers. The authors determined nine kinds of major elements in superphosphate, the most important phosphate fertilizer, by X-ray fluorescence spectrometry. The detection range of SiO2, Al2O3, TFe2O3, MnO, MgO, CaO, Na2O, K2O and P2O5 is 15.

Reducing environmental risk by improving N management in intensive Chinese agricultural systems.

Excessive N fertilization in intensive agricultural areas of China has resulted in serious environmental problems because of atmospheric, soil, and water enrichment with reactive N of agricultural origin. This study examines grain yields and N loss pathways using a synthetic approach in 2 of the most intensive double-cropping systems in China: waterlogged rice/upland wheat in the Taihu region of east China versus irrigated wheat/rainfed maize on the North China Plain. When compared with knowledge-based optimum N fertilization with 30-60% N savings, we found that current agricultural N practices with 550-600 kg of N per hectare fertilizer annually do not significantly increase crop yields but do lead to about 2 times larger N losses to the environment.