Effects of hydroxyapatite and modified biochar derived from Camellia oleifera fruit shell on soil Cd contamination and N2O emissions

Cadmium (Cd) contamination threatens cocoa farming in the province of Bagua in Amazonas, Peru. This study reports our assessment of Cd concentrations in cocoa farm soils, and in cocoa roots, leaves, testa, and cotyledon, thus evaluating the magnitude of the problem caused by Cd exposure. For our analysis, we sampled agricultural soil, cocoa roots, leaves and pods at 29 farms in the province of Bagua. Concentrations of Cd in each of the samples were measured and correlated with selected variables at each sampling site. Within our collection of samples, Cd levels showed great variability. In soil, Cd concentrations ranged between 1.02 and 3.54 mg kg−1. Concentrations of this metal within cocoa trees measured from roots, leaves, testa, and cotyledon, Cd ranged from 0.49 mg kg−1 to 2.53 mg kg−1. The cocoa trees exhibited variable degrees of allocation Cd from the soil to their tissues and thus considerable variation among themselves. We found that Cd amounts in roots were up to five times more concentrated than Cd levels in the soils and 2.85 times [Cd] the amounts found in cotyledon. Soil pH is a key variable enabling the uptake of this metal. Most importantly, our evaluation determined that measurements from the majority of farms exceeded the maximum permissible limits established by Peruvian and European legislation.

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Biochar derived from spent mushroom substrate reduced N2O emissions with lower water content but increased CH4 emissions under flooded condition from fertilized soils in Camellia oleifera plantations

Chemosphere ◽

10.1016/j.chemosphere.2021.132110 ◽

2022 ◽

Vol 287 ◽

pp. 132110

Author(s):

Xintong Xu ◽

Xi Yuan ◽

Qiang Zhang ◽

Qixuan Wei ◽

Xiaojun Liu ◽

...

Keyword(s):

Water Content ◽

N2o Emissions ◽

Camellia Oleifera ◽

Spent Mushroom Substrate ◽

Ch4 Emissions ◽

Lower Water Content

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Biochar Is Comparable to Dicyandiamide in the Mitigation of Nitrous Oxide Emissions from Camellia oleifera Abel. Fields

Forests ◽

10.3390/f10121076 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1076 ◽

Cited By ~ 9

Author(s):

Bangliang Deng ◽

Haifu Fang ◽

Ningfei Jiang ◽

Weixun Feng ◽

Laicong Luo ◽

...

Keyword(s):

Nitrous Oxide ◽

Agricultural Soil ◽

Fold Increase ◽

N Fertilization ◽

Nitrous Oxide Emissions ◽

N2o Emissions ◽

Nitrification Inhibitors ◽

Camellia Oleifera ◽

N Application ◽

Oil Plant

Research Highlights: Intensive nitrogen (N) application for agricultural purposes has substantially increased soil nitrous oxide (N2O) emissions. Agricultural soil has great potential in the reduction of N2O emissions, and applications of biochar and nitrification inhibitors may be useful for mitigating agricultural soil N2O emissions. Background and Objectives: Camellia oleifera Abel. is an important woody oil plant in China. However, intensive N input in C. oleifera silviculture has increased the risk of soil N2O emissions. As an important greenhouse gas, N2O is characterized by a global warming potential at a 100-year scale that is 265 times that of carbon dioxide. Thus, mitigation of soil N2O emissions, especially fertilized soils, will be crucial for reducing climate change. Materials and Methods: Here, we conducted an in situ study over 12 months to examine the effects of C. oleifera fruit shell-derived biochar and dicyandiamide (DCD) on soil N2O emissions from a C. oleifera field with intensive N application. Results: A three-fold increase of cumulative soil N2O emissions was observed following N application. Cumulative N2O emissions from the field with N fertilization were reduced by 36% and 44% with biochar and DCD, respectively. While N2O emissions were slightly deceased by biochar, the decrease was comparable to that by DCD. Conclusions: Results indicated that biochar may mitigate soil N2O emissions substantially and similarly to DCD under specific conditions. This result should be examined by prolonged and multi-site studies before it can be generalized to broader scales.

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Distribution of nutrients in Camellia oleifera Abel. and their correlation with soil nutrients over the period of fruit maturation

Bangladesh Journal of Botany ◽

10.3329/bjb.v49i3.49530 ◽

2020 ◽

Vol 49 (3) ◽

pp. 499-505

Author(s):

Jia Luo ◽

Xiaoling Zhou ◽

Yuxin Tian ◽

Yongzhong Chen ◽

Longshen Chen

Keyword(s):

Soil Nutrients ◽

Scientific Basis ◽

Complex Interaction ◽

Nutrient Elements ◽

Camellia Oleifera ◽

Soil N ◽

Fruit Maturation ◽

Mn Content ◽

Macro Element ◽

Soil Cd

In order to provide the scientific basis for Camellia oleifera nutrient diagnosis and fertilizer formulation, the correlation between soil nutrients and nutrient elements in different organs of Camellia oleifera was studied in ten-year-old Camellia oleifera in Changning city. The results showed that among the nutrient elements, the content of N and P were the highest and lowest in various organs, respectively. Correspondingly, the highest content of macro-element in the soil was Ca. Besides, there were diverse relations among nutrients in soil and those in different organs of Camellia oleifera. Soil nutrients were most closely associated with that of stem, so was soil N, Zn, Mn, Pb and K with the plant nutrients. In addition, soil exchangeable Mn content was positively correlated with nutrients of different organs. Moreover, soil N showed highly significant correlation with N content in stem while soil Cd content was negatively correlated with Cd content of all organs. Thus, there prevails a complex interaction of nutrient elements in the soil and exists a synergy or/and antagonism effect among of elements in plants. Consequently, the understanding of effect of interaction between different elements might provide better idea for achieving the precise fertilization, which could further reduce costs and increase production.

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Remediation Techniques for Cadmium-Contaminated Dredged River Sediments after Land Disposal

Sustainability ◽

10.3390/su13116093 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6093

Author(s):

Changsong Zhang ◽

Xueke Zang ◽

Zhenxue Dai ◽

Xiaoying Zhang ◽

Ziqi Ma

Keyword(s):

River Sediments ◽

Environmental Safety ◽

Current Status ◽

Soil Leaching ◽

Cd Contamination ◽

Land Disposal ◽

Stabilization Technique ◽

Cd Removal ◽

Timely Treatment ◽

Soil Cd

This paper examines the remediation techniques of cadmium (Cd)-contaminated dredged river sediments after land disposal in a city in East China. Three remediation techniques, including stabilization, soil leaching, and phytoremediation, are compared by analyzing the performance of the techniques for Cd-contaminated soil remediation. The experimental results showed that the stabilization technique reduced the leaching rate of soil Cd from 33.3% to 14.3%, thus effectively reducing the biological toxicity of environmental Cd, but the total amount of Cd in soil did not decrease. Leaching soil with citric acid and oxalic acid achieved Cd removal rates of 90.1% and 92.4%, respectively. Compared with these two remediation techniques, phytoremediation was more efficient and easier to implement and had less secondary pollution, but it took more time, usually several years. In this study, these three remediation techniques were analyzed and discussed from technical, economic, and environmental safety perspectives by comprehensively considering the current status and future plans of the study site. Soil leaching was found to be the best technique for timely treatment of Cd contamination in dredged river sediments after land disposal.

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Analysis of N2O emissions from the agro-ecosystem in Fujian Province

CHINESE JOURNAL OF ECO-AGRICULTURE ◽

10.3724/sp.j.1011.2014.30392 ◽

2014 ◽

Vol 22 (2) ◽

pp. 225-233

Author(s):

Yanchun LI ◽

Yixiang WANG ◽

Chengji WANG ◽

Bailong ZHENG ◽

Yibin HUANG

Keyword(s):

N2o Emissions ◽

Fujian Province

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Impact of sewage sludge applications on the biogeochemistry of soils

Water Science & Technology ◽

10.2166/wst.2008.0001 ◽

2008 ◽

Vol 57 (6) ◽

pp. 963-963

Author(s):

D. Devaney ◽

A. R. Godley ◽

M. E. Hodson ◽

K. Purdy ◽

S. Yamulki

Keyword(s):

Sewage Sludge ◽

N2o Emissions ◽

Correct Version ◽

Main Text

Unfortunately an incorrect version of Figure 4 appears on p517 of this paper; the correct version is as printed below. A sentence (“Increased N2O emissions…. Conversely”) should then also be deleted from the corresponding paragraph of the main text as printed on pp516–517; the correct version of this paragraph is also given below. The authors and publisher regret any confusion or inconvenience this may have caused.

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Biochar and urease inhibitor mitigate NH3 and N2O emissions and improve wheat yield in a urea fertilized alkaline soil

Scientific Reports ◽

10.1038/s41598-021-96771-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Khadim Dawar ◽

Shah Fahad ◽

M. M. R. Jahangir ◽

Iqbal Munir ◽

Syed Sartaj Alam ◽

...

Keyword(s):

Nitrous Oxide ◽

Grain Yield ◽

Block Design ◽

N Uptake ◽

Nitrous Oxide Emissions ◽

N2o Emissions ◽

Urease Inhibitor ◽

Alkaline Soil ◽

Total N ◽

N Assimilation

AbstractIn this study, we explored the role of biochar (BC) and/or urease inhibitor (UI) in mitigating ammonia (NH3) and nitrous oxide (N2O) discharge from urea fertilized wheat cultivated fields in Pakistan (34.01°N, 71.71°E). The experiment included five treatments [control, urea (150 kg N ha−1), BC (10 Mg ha−1), urea + BC and urea + BC + UI (1 L ton−1)], which were all repeated four times and were carried out in a randomized complete block design. Urea supplementation along with BC and BC + UI reduced soil NH3 emissions by 27% and 69%, respectively, compared to sole urea application. Nitrous oxide emissions from urea fertilized plots were also reduced by 24% and 53% applying BC and BC + UI, respectively, compared to urea alone. Application of BC with urea improved the grain yield, shoot biomass, and total N uptake of wheat by 13%, 24%, and 12%, respectively, compared to urea alone. Moreover, UI further promoted biomass and grain yield, and N assimilation in wheat by 38%, 22% and 27%, respectively, over sole urea application. In conclusion, application of BC and/or UI can mitigate NH3 and N2O emissions from urea fertilized soil, improve N use efficiency (NUE) and overall crop productivity.

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