comments on "Reconstruction of spatially detailed global map of NH4+ and NO3- application in synthetic nitrogen fertilizer"

2016 ◽  
Author(s):  
Chaoqun Lu
Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2429
Author(s):  
Xiaoru Fan ◽  
Zekai Chen ◽  
Zihan Niu ◽  
Ruiyao Zeng ◽  
Jingmin Ou ◽  
...  

Synthetic nitrogen fertilizer substitution (NSS) with different types of organic material is a cleaner agricultural practice for reducing the application of synthetic N input in farmlands while also relieving the environmental issues caused by the discharge of organic wastes. However, the effects of the NSS practice on crop yields, being the primary objective of agricultural activity, is still uncertain in China. This study conducted a meta-analysis to assess the impacts of the NSS practices with different types of organic materials on crop yields. Results showed that the average crop yield was increased by 3.4%, with significant differences under NSS, thereby demonstrating that this practice contributed to improving crop yields, especially of rice and maize. According to published reports, the NSS practices involving chicken manure, pig manure, and crop straw increased crop yields by 4.79, 7.68, and 3.28%, respectively, with significant differences, thus demonstrating the superior effects needed for replacing synthetic N fertilizer. Moreover, substitution ratios (SR) between 0% and 60% could be suggested when using the NSS practice, with the high SR recommended when the original soil fertility was adequate for crops. Considering the long-term effects of applied organic materials, improving the grain yield with the NSS practice should be expected in the long-term. By effectively applying the NSS, this study attempted to scientifically decide on the type of organic materials and the appropriate SR based on the conditions of the soil and the crop. The results provide research information for the development of clean agricultural production and food security in China.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1734
Author(s):  
Modupe Olufemi Doyeni ◽  
Urte Stulpinaite ◽  
Ausra Baksinskaite ◽  
Skaidre Suproniene ◽  
Vita Tilvikiene

The need to find and maximize the use of alternative sources of nutrients for plants and soil environment have been on the forefront of research in sustainable agriculture. These alternatives have to be affordable, accessible, reproduceable, and efficient to compete with established inorganic fertilizers while at the same time reduce any potential negative impacts on the environment. We aimed to evaluate the effectiveness of digestate fertilization in an agricultural system over a period of three years. The digestate utilized in the study consisted of animal waste-based digestates, namely pig manure digestate, chicken manure digestate, and cow manure digestate, and were compared with synthetic nitrogen fertilizer. Every year, the digestate and the synthetic nitrogen fertilizer were split applied at the rate of 90 and 80 kg N ha−1. The soil chemical composition after three years of fertilization showed a slight decrease, significantly different nitrogen and carbon changes while phosphorus and potassium were significantly higher in the digestate treatments. The third year of digestate application showed higher grain yield than previous years and the yield from the digestate treatments were significantly different from the synthetic nitrogen fertilizer. The nitrogen use efficiency for the three years was in the range of 20–25 percent in the digestate treatments, with a strong correlation between the nitrogen use efficiency and the grain yield. There were varied results in the grain quality and straw quality in the digestate and synthetic nitrogen fertilizer with no clear trend observed. Our results showed a relatively high potential of animal waste digestates over the short to mid-term use with a positive result obtained in comparison to synthetic nitrogen fertilizer under favorable climatic conditions.


2021 ◽  
Vol 12 ◽  
Author(s):  
Christopher R. Dumigan ◽  
Jade Muileboom ◽  
Jake Gregory ◽  
Anuja Shrestha ◽  
Omar Hewedy ◽  
...  

Plants can adapt to their surroundings by hosting beneficial bacteria that confer a selective advantage in stressful conditions. Endophytes are a class of beneficial bacteria that exist within the internal spaces of plants and many species can improve plant nitrogen use efficiency. Nitrogen is an essential plant macronutrient, and is often a limiting factor to plant growth, especially in cereal crops such as maize. Every year farmers apply over 100 million metric tonnes of synthetic nitrogen fertilizer to meet the growing demand for stable food crops. Breeding efforts in maize over the past several decades has focused heavily on yield in response to nitrogen inputs, and so may have selected against adaptations that allow plants to survive in nitrogen stressed conditions. Data suggests that our heavy dependence on synthetic nitrogen fertilizer is not sustainable in the long term, and so there is on-going research efforts to reduce and replace this currently essential part of modern agriculture. Bacteria that improve plant tolerance to nitrogen stressed environments would allow farmers to reduce the amount of fertilizer they apply. The selection of maize under high nitrogen conditions to create modern varieties may have caused the plant to lose these beneficial bacteria that allowed wild maize ancestors to thrive in low nitrogen soil. Here in this study, we examine the root and shoot microbiomes of the wild ancestor of all maize, Parviglumis, and an ancient Mexican landrace (Mixteco) from Oaxaca, the area of early maize diversification. Both of these maize genotypes have thrived for thousands of years with little to no nitrogen inputs and so we hypothesized that they host beneficial bacteria that allow them to thrive in nitrogen stressed conditions. We identified multiple root endophyte species from each ancient maize relative that increased the growth of annual ryegrass (model maize relative) under nitrogen starvation. Furthermore, research infers these strains were vertically transmitted to new generations of plants, potentially through seed, indicating selection pressure for Parviglumis and Mixteco to maintain them in their microbiome.


2021 ◽  
Vol 49 (5) ◽  
pp. 93-101
Author(s):  
Luke Struckman

This intervention examines commodity grain and oilseed farmers’ over reliance on synthetic nitrogen fertilizer in North America. Most grain and oilseed farmers apply synthetic nitrogen fertilizer at rates higher than necessary in order to ensure maximum yields. At the same time, high fertilizer application rates lead to increased farm input expenses and generate significant amounts of water pollution and excessive greenhouse gas emissions. A number of low-cost alternative approaches have been developed which can significantly reduce or eliminate the need for synthetic nitrogen fertilizer while maintaining farm profitability. But such practices have only seen limited adoption by Canadian and US farmers. This is despite significant production cost savings and environmental benefits. A number technological and institutional factors work in combination to lock farmers into production models requiring large amounts of synthetic nitrogen fertilizer. They include crop varieties bred to thrive in artificially high nitrogen soil conditions, conventional tillage practices, restrictive financial arrangements, largely unenforced water quality laws, and non-diverse marketing outlets. These technological and institutional lock-ins are significant barriers to the adoption of alternative crop production practices that are less reliant upon synthetic nitrogen fertilizer.


2017 ◽  
Author(s):  
Zainal Muktamar ◽  
Dora Putri ◽  
Nanik Setyowati

Organic fertilizer is capable to decrease the use of synthetic fertilizer due to release of plant nutrients and improvement of other soil properties. The objective of this experiment was to compare the growth and yield of green mustard as affected by cattle manure and litter compost. The experiment was conducted employing Completely Randomized Design with 8 treatments. Treatments included litter compost and cattle manure at rate of 25 Mg ha-1 and 15, 20, 25 Mg ha-1 with addition of 1.85 g nitrogen fertilizer per plant, respectively. Each treatment was replicated 5 times. Soil used in this experiment was Ultisol collected at depth of 0-20 cm. Five kg of soil was mixed with organic fertilizer according to each treatment and placed in 10 kg polybag. Green mustard was planted to each polybag. Nitrogen fertilizer was applied a week after planting. The experiment revealed that application of litter compost and cattle manure at rate 25 Mg ha-1 with additional nitrogen fertilizer resulted in higher green mustard fresh weight per plant and number of leaves. On the other hand, application of both organic fertilizers at rate of 25 Mg ha-1 without addition nitrogen fertilizer as other treatments did not provide significant differences on most variables observed. This indicated that application of organic fertilizer is able to reduce synthetic nitrogen fertilizer for green mustard production.


1948 ◽  
Vol 40 (7) ◽  
pp. 1178-1183 ◽  
Author(s):  
K. G. Clark ◽  
J. Y. Yee ◽  
K. S. Love

2018 ◽  
Vol 25 (1) ◽  
pp. 314-326 ◽  
Author(s):  
Rongting Xu ◽  
Hanqin Tian ◽  
Shufen Pan ◽  
Stephen A. Prior ◽  
Yucheng Feng ◽  
...  

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 864F-864
Author(s):  
Hector R. Valenzuela ◽  
Randall Hamasaki

Experiments were conducted to evaluate the effect of two different compost materials and several compost: synthetic N fertilizer ratios on the growth, yields, and nematode infestations in head and semi-head lettuce, and basil. Treatments were homemade compost at 25 MT/ha, Amend compost at 25 MT/ha, N alone at 150 kg·ha–1, and Amend compost at 25 MT/ha plus 0, 100, 200 or 300 kg N/ha. The basil trial followed the lettuce experiment on the same treatment beds to evaluate the long-term effects of compost applications. Compost plus 100 kg N/ha resulted in the greatest yields of 12 to 24 MT/ha for the semi-head and head lettuce trials, respectively. Basil was harvested for 6 months during a 10-month growth cycle. Highest basil yields of 64 MT/ha and canopy growth were obtained with a combination of compost plus synthetic N fertilizer, with 300 kg N/ha required for maximum yields during the 6-month harvesting period. By the last sampling date nematode counts were lowest for plots that received compost treatment alone and highest for the controls and for plants receiving synthetic N fertilizer alone.


Sign in / Sign up

Export Citation Format

Share Document