Systematic review of metrics used to characterize dietary nutrient supply from household consumption and expenditure surveys

Objective: To review existing publications using Household Consumption & Expenditure Survey (HCES) data to estimate household dietary nutrient supply to (1) describe scope of available literature, (2) identify the metrics reported and parameters used to construct these metrics, (3) summarize comparisons between estimates derived from HCES and individual dietary assessment data, and (4) explore the demographic and socioeconomic sub-groups used to characterize risks of nutrient inadequacy. Design: This study is a systematic review of publications identified from online databases published between 2000 to 2019 that used HCES food consumption data to estimate household dietary nutrient supply. Further publications were identified by “snowballing” the references of included database-identified publications. Setting: Publications using data from low- and lower middle income countries Results: In total, 58 publications were included. Three metrics were reported that characterized household dietary nutrient supply: apparent nutrient intake per adult-male equivalent per day (n=35), apparent nutrient intake per capita per day (n=24), and nutrient density (n=5). Nutrient intakes were generally overestimated using HCES food consumption data, with several studies finding sizeable discrepancies compared to intake estimates based on individual dietary assessment methods. Sub-group analyses predominantly focused on measuring variation in household dietary nutrient supply according to socioeconomic position and geography. Conclusion: HCES data are increasingly being used to assess diets across populations. More research is needed to inform the development of a framework to guide the use of and qualified interpretation of dietary assessments based on these data.

Seabird-Derived Nutrients Supply Modulates the Trophic Strategies of Mixotrophic Corals

The ability of corals to modulate their nutrition strategy in response to variable nutrient supply remains poorly understood, limiting our understanding of energy flow in coral reef ecosystems and thus our comprehension of their resilience to global changes. We used a naturally occurring nutrient gradient along the reef flat of two seabird-inhabited islets in the SW Pacific to characterize spatiotemporal fluctuations in coastal nutrient availability, and how it modulates the trophic response of the mixotrophic coral Pocillopora damicornis. The clear gradients in dissolved [NOx] and δ15N values of macroalgae and both P. damicornis tissues and symbionts observed along the reef flat during the dry and the rainy season revealed that seabird-derived-N is supplied year-round to the reef flat. Yet, nitrogen isotope values of macroalgae show that the seabirds’ effect on coral reefs varies with sites and seasons. Metrics derived from the SIBER framework revealed that coral nutrition seasonally favored autotrophy when exposed to higher seabird guano concentrations and at inshore stations, while heterotrophy dominated in corals less exposed to seabird-derived nutrient supply. P. Damicornis is therefore able to cope with large changes in nitrogen supply induced by seabird island communities by switching between autotrophy and heterotrophy. These results shed light on the flexibility of resource sharing within the coral-algae symbiosis and highlight the importance of seabird populations to the functioning of coral reef ecosystems.

Energy capture and carbon assimilation.

This chapter focuses on energy capture and carbon assimilation of fruit trees. It discusses the factors affecting photosynthesis and respiration, including temperature, carbon dioxide concentration, nutrient supply, water availability, oxygen, and carbohydrates.

Effects of phosphorus and iron on biomass production and nutrients partitioning in soybean cultivars under water stress condition

A pot experiment was conducted to investigate the effects of P and Fe application on the biomass production and nutrients partitioning of two soybeans (Glycine max. L. Merr) cultivars grown in carbonated chernoziom (low in Fe and P) under water stress conditions. P and Fe were applied at two levels (0 and 100 mg P kg-1 soil; 0 and 5 mg Fe kg-1 soil). Control plants were grown at 70% water holding capacity (WHC) while their counterparts were subjected to 35% WHC water stress at initial flowering stage for two weeks. Considerable variability was observed in leaves, roots dry mass accumulation and nodulation among the soybean cultivars (Zodiac, Licurici) at both P and Fe levels in relation to water regimes. The results showed that drought significantly reduced biomass production irrespective of nutrient supply and its adverse effect was more pronounced at low nutrient supply. Leaf development and nodules growth were the most sensitive to water deficit and insufficient nutrient supply. Adequate P and Fe supply increased dry matter production and nutrient concentrations for soybean cultivars. Phosphorus concentration in plant parts was significantly higher at nil Fe compared with Fe application. Phosphorus application decreased Fe allocation to the leaves. The experimental results demonstrated that there was a positive effect of P and Fe adequate nutrition on P use efficiency. Hence, the sufficient phosphorus and iron supply maintained growth at high level, improved P and Fe status and partially alleviated drought effect on soybean plants.

Growth and Yield Responses of Red Onions to Different Nutrient Availability in Fertigation System

Nutrient availability affected plant growth and yield. This study aimed to examine the effect of interval application and fertigation frequency toward plant growth and yield, and further determined the most proper fertigation interval and frequency that support the highest plant growth and yield. Experiment was arranged in Split plot randomized Completely Block Design. The main plots were interval of nutrient application, i.e., 3 days interval, 6 days interval, 9 days interval. The sub plots were the frequency of nutrient application, i.e., once/day, 2 times/day, 3 times/day. The plot size for each treatment was 2.5 m×1.3 m and plant spacing was 15 cm×20 cm. Space between beds was 1 m. Red onions (Bima variety) were planting in a raised bed covered with silver black polythene mulch. Before planting, 5 ton/ha manure and 1 ton/ha lime were mix with the soil. Fipronil 1.5% was applied with dose 8 kg/ha to control grubs. Nutrient was mixture between liquid organic fertilizer (7.5 mL/L), rabbit urin (5mL/L) and AB Mix (7.5 mL/L A+7.5 mL B). The nutrient was dispensed 150 mL/plant according to treatment using fertigation system operated remotely using Internet of Things. The nutrient was given from 14 DAP (Days After Planting) until 68 DAP. Irrigation water was dispensed 150 mL daily in the same way. The interval of fertigation significantly affected the growth of red onion (plant height, number of leaves and number of yield). Three days interval of nutrient supply resulted in the tallest plant, highest number of plant leaves, and highest number of bulbs. However, the frequency of nutrient supply daily significantly affected the yield of red onion. The application of nutrient three times/day provided the highest yield (economical dry weight). Further research to examine the effect of fertigation of red onion quality is required.

The Patterns of Male and Female Flowers in Flowering Stage May Not Be Optimal Resource Allocation for Fruit and Seed Growth

Changes in the proportions of male and female flowers in monoecious plants in response to external environmental conditions are directly related to the reproductive fitness of plants. The monoecious cucumber (Cucumber sativus) plant was used in this study to assess the responses of sex differentiation and the breeding process to nutrient supply and the degree of artificial pollination using pollen solutions of different concentrations. We found that the nutrient supply significantly improved the number of female flowers, while pollination treatments did not obviously increase the number of male flowers. Continuous pollination changed the number of female flowers especially in the later stage of the pollination experiment. Therefore, pollination changed the ratio of male and female flowers in the flowering stage of cucumber. Pollination treatment affected the fruit growth, seed set, and fruit yield. The number of fruit, fruit set percentage, and total seeds per plant did not increase with the pollination level, but individual fruit weight and seed number in one fruit did increase. The differentiation of male and female flowers in the flowering stage of cucumber is a response to nutrient and pollination resources, but this response is not the optimal resource allocation for subsequent fruit development and seed maturity, which suggests that the response of plants to external environment resources is short-term and direct.

Coated Diammonium Phosphate Combined With Humic Acid Improves Soil Phosphorus Availability and Photosynthesis and the Yield of Maize

Controlled release phosphorus (P) fertilizers and humic acid (HA) applications are two effective and significant techniques or measures for preventing P loss and enhancing maize development. However, the underlying physiological mechanism of how the controlled release P fertilizers combined with HA affect the maize production and P-use efficiency (PUE) remains unknown. The effects of applying coated diammonium phosphate (CDAP) and HA together on soil nutrient supply intensity, soil phosphatase activity, photosynthesis, endogenous hormone contents, and yield of maize, as well as PUE, were examined in this study. In a pot experiment, two types of P fertilizers—CDAP and diammonium phosphate (DAP)– as well as two HA application rates (0 and 45 kg ha–1) and two P levels (60 and 75 kg P2O5 ha–1) were utilized. Results showed that the key elements that influence the growth and yield of the maize were the availability of P content in soil, plant photosynthesis, and hormone levels. The combination of CDAP and HA had a greater impact on yield and PUE over the course of 2 years than either DAP alone or DAP combined with HA. Besides, using CDAP in combination with HA increased the yield and PUE by 4.2 and 8.4%, respectively, as compared to the application of CDAP alone at 75 kg P2O5 ha–1. From the twelve-leaf to milk stages, the available P content in the soil was increased by an average of 38.6% with the combination of CDAP and HA compared to the application of CDAP alone at 75 kg P2O5 ha–1. In addition, the application of CDAP combined with HA boosted the activities of ATP synthase, as well as the content of cytokinin (CTK), and hence improved the maize photosynthetic rate (Pn). When compared to the application of CDAP alone or DAP combined with HA, the Pn of CDAP + HA treatments was enhanced by 17.9–35.1% at the same P rate. In conclusion, as an environmentally friendly fertilizer, the combined application of CDAP and HA improved the intensity of the soil nutrient supply, regulated photosynthetic capabilities, and increased the yield and PUE, which is important for agricultural production, P resource conservation, and environmental protection.