4 research outputs found
Soil N2O and CH4 emissions from fodder maize production with and without riparian buffer strips of differing vegetation
Purpose Nitrous oxide (N2O) and methane (CH4)
are some of the most important greenhouse gases in
the atmosphere of the 21st century. Vegetated riparian bufers are primarily implemented for their water
quality functions in agroecosystems. Their location
in agricultural landscapes allows them to intercept
and process pollutants from adjacent agricultural
land. They recycle organic matter, which increases
soil carbon (C), intercept nitrogen (N)-rich runof
from adjacent croplands, and are seasonally anoxic.
Thus processes producing environmentally harmful
gases including N2O and CH4 are promoted. Against this context, the study quantifed atmospheric losses
between a cropland and vegetated riparian bufers
that serve it.
Methods Environmental variables and simultaneous
N2O and CH4 emissions were measured for a 6-month
period in a replicated plot-scale facility comprising
maize (Zea mays L.). A static chamber was used to
measure gas emissions. The cropping was served by
three vegetated riparian bufers, namely: (i) grass
riparian bufer; (ii) willow riparian bufer and; (iii)
woodland riparian bufer, which were compared with
a no-bufer control.
Results The no-bufer control generated the largest cumulative N2O emissions of 18.9 kg ha−1
(95%
confdence interval: 0.5–63.6) whilst the maize crop
upslope generated the largest cumulative CH4 emissions (5.1±0.88 kg ha−1
). Soil N2O and CH4-based
global warming potential (GWP) were lower in
the willow (1223.5±362.0 and 134.7±74.0 kg
CO2-eq. ha−1 year−1
, respectively) and woodland
(1771.3±800.5 and 3.4±35.9 kg CO2-eq. ha−1
year−1
, respectively) riparian bufers.
Conclusions Our results suggest that in maize production and where no riparian bufer vegetation is
introduced for water quality purposes (no bufer control), atmospheric CH4 and N2O concerns may result.The Department of Higher Education and Training (New Generation Gap of Academics Program) and National Research Foundation-Thuthuka.https://www.springer.com/journal/11104dm2022Plant Production and Soil Scienc
Maize growth and yield as affected by different soil fertility regimes in a long term trial
Maize is the world’s third most important cereal after wheat and rice. It serves as a staple food to more than 1.2 billion of the world population. However, its production is threatened by declining soil fertility; mainly due to low inputs of fertilizers containing major elements to replenish lost soil nutrients and unsustainable soil tillage practices linked to mono-cropping. To examine the influence of N, P and K and residual compost on maize growth and yield, an experiment was carried out at the Hatfield Experimental Farm of the University of Pretoria. Utilizing the long-term maize trial, controls (0 and W), seven inorganic fertilizer treatments (N, P, K, NP, NK, PK & NPK) and seven organic + inorganic fertilizer treatments (WN, WP, WK, WNP, WNK, WPK & WNPK) were used. The influence of these fertilizer and residual compost treatments on maize seed viability (germination), plant growth, reproductive development, pollen performance, grain yield parameters, yield and grain yield water-use efficiency was investigated.
Higher seed viability was associated with balanced soil nutrient status (WNPK & NPK), whilst deficient soil nutrient status (0, N, P & K) resulted in lower seed viability. Plant growth (plant height, total dry mass and LAI) and reproductive development (tassel length, ear length, and days to tasseling and silking) were positively influenced by a balanced soil nutrient status and residual compost. Deficiencies in soil nutrients restricted maize plant growth and delayed reproductive development. This highlighted the importance of a balanced soil nutrient status in attaining a vigorous crop and good reproductive development.
Soil nutrient deficiencies (0, P & K treatments) enhanced the production of pollen (mass per plant), but resulted in low pollen quality (viability and germination). Balanced soil nutrient status (WNPK & NPK) resulted in the production of high quality pollen (viability and germinability), which however had a low mass. In both 2012/2013 and 2013/2014 seasons, maize grain components; cob length, number of kernel rows per cob, number of kernels per row, mass per kernel and mass of 100 kernels were positively influenced by balanced soil nutrient status. Grain yield and water use efficiency were also positively influenced by a balanced soil nutrient status (WNPK & NPK), whilst deficient soil nutrient status had a negative effect.Dissertation (MScAgric)--University of Pretoria, 2015.tm2015Plant Production and Soil ScienceMScAgricUnrestricte
Evaluating the potential of different carbon sources to promote denitrification
Please read abstract in the article.https://www.cambridge.org/core/journals/journal-of-agricultural-sciencehj2021Plant Production and Soil Scienc
Soil methane (CH4) fluxes in cropland with permanent pasture and riparian buffer strips with different vegetation
Please read abstract in the article.South African Department of Higher Education and Training; National Research Foundation-Thuthuka and Rothamsted Research through its Institute Strategic Programme.https://wileyonlinelibrary.com/journal/jpln2022-12-15hj2022Plant Production and Soil Scienc