Search scope:
排序： Display mode:
responses of soil organic carbon dynamics to nitrogen addition in different layers: a case study in an agroecosystem RESEARCH ARTICLE
Frontiers of Agricultural Science and Engineering 2024, Volume 11, Issue 2, Pages 314-325 doi: 10.15302/J-FASE-2024565
Empirical research indicates that heightened soil nitrogen availability can potentially diminish microbial decomposition of soil organic carbon (SOC). Nevertheless, the relationship between SOC turnover response to N addition and soil depth remains unclear. In this study, soils under varying N fertilizer application rates were sampled up to 100 cm deep to examine the contribution of both new and old carbon to SOC across different soil depths, using a coupled carbon and nitrogen isotopic approach. The SOC turnover time for the plot receiving low N addition (250 kg·ha−1·yr−1 N) was about 20−40 years. Conversely, the plot receiving high N (450 kg·ha−1·yr−1 N) had a longer SOC turnover time than the low N plot, reaching about 100 years in the upper 10−20 cm layer. The rise in SOC over the entire profile with low N addition primarily resulted from an increase in the upper soil (0−40 cm) whereas with high N addition, the increase was mainly from greater SOC in the deeper soil (40−100 cm). Throughout the entire soil layer, the proportion of new organic carbon derived from maize C4 plant sources was higher in plots treated with a low N rate than those treated with a high N rate. This implies that, in contrast to low N addition agricultural practices, high N addition predominantly enhances the soil potential for fixing SOC by transporting organic matter from surface soils to deeper layers characterized by more stable properties. This research offers a unique insight into the dynamics of deep carbon under increased N deposition, thereby aiding in the formulation of policies for soil carbon management.
Keywords： case study agroecosystem Discrepant responses soil
FOR USE IN AGROECOSYSTEM IMPROVEMENT IN SEMI-ARID AREAS WITH A FOCUS ON CENTRAL ANATOLIA, TURKEY
Frontiers of Agricultural Science and Engineering 2021, Volume 8, Issue 4, Pages 568-582 doi: 10.15302/J-FASE -2019270
Keywords： actinorrhizal trees / agroforestry / climate change / ecosystem restoration
Transmission of antibiotic resistance genes in agroecosystems: an overview
Jizheng HE, Zhenzhen YAN, Qinglin CHEN
Frontiers of Agricultural Science and Engineering 2020, Volume 7, Issue 3, Pages 329-332 doi: 10.15302/J-FASE-2020333
The use of antibiotics in human medicine and animal husbandry has resulted in the continuous release of antibiotics into the environment, which imposes high selection pressure on bacteria to develop antibiotic resistance. The spread and aggregation of antibiotic resistance genes (ARGs) in multidrug-resistant pathogens is one of the most intractable clinical challenges. Numerous studies have been conducted to profile the patterns of ARGs in agricultural ecosystems, as this is closely related to human health and wellbeing. This paper provides an overview of the transmission of ARGs in agricultural ecosystems resulting from the application of animal manures and other organic amendments. The future need to control and mitigate the spread of antibiotic resistance in agricultural ecosystems is also discussed, particularly from a holistic perspective, and requires multiple sector efforts to translate fundamental knowledge into effective strategies.
Keywords： agroecosystem antibiotic resistance public health soil-plant system
Frontiers of Agricultural Science and Engineering 2024, Volume 11, Issue 2, Pages 303-313 doi: 10.15302/J-FASE-2023502
Awareness of how soil properties vary over agroecosystems (AES) is essential for understanding soil potentials and improving site-specific agricultural management strategies for a sustainable ecosystem. This study examined the characteristics of soil quality attributes and implications for agriculture in the Choke Mountain watershed in Ethiopia. Forty-seven composite soil samples (0–20 cm deep) were collected from lowland and valley fragmented (AES 1), midland plain with black soil (AES 2), midland plain with brown soil (AES 3), sloppy midland land (AES 4), and hilly and mountainous highlands (AES 5). Ten of 15 soil quality properties were significant (P < 0.05 or 0.01), including silt, exchangeable bases, cation exchange capacity, percent base saturation, pH, organic matter, total nitrogen and available phosphorous (P) across the five AES. However, all properties were variable with coefficients of variation from 7% (total porosity) to 169% (available P) across the AES. Although AES 2 and 3 are affected by waterlogging and acidity, these two have better prospects for agriculture, but AES 1, 4, and 5 are unsuitable for agriculture because of soil erosion. Therefore, appropriate and applicable soil management strategies, particularly lime application and organic fertilizer, are fundamental to reversing soil acidity and improving soil fertility.
Keywords： agroecosystem Choke Mountain watershed coefficients of variation Ethiopia soil quality indicator
Frontiers of Agricultural Science and Engineering 2021, Volume 8, Issue 3, Pages 416-431 doi: 10.15302/J-FASE-2021412
Absolute yield and land use efficiency can be higher in multicrops. Though this phenomenon is common, it is not always the case. Also, these two benefits are frequently confused and do not necessarily occur together. Cropping choices become more complex when considering that multicrops are subject to strong spatial and temporal variation in average soil moisture, which will worsen with climate change. Intercropping in agroecosystems is expected to buffer this impact by favoring resistance to reduced humidity, but there are few empirical/experimental studies to validate this claim. It is not clear if relatively higher multicrop yield and land use efficiency will persist in the face of reduced soil moisture, and how the relation between these benefits might change. Here, we present a relatively simple framework for analyzing this situation. We propose a relative multicrop resistance (RMR) index that captures all possible scenarios of absolute and relative multicrop overyield under water stress. We dissect the ecological components of RMR to understand the relation between higher multicrop yield and land use efficiency and the ecological causes of different overyield scenarios. We demonstrate the use of this framework with data from a 128 microplot greenhouse experiment with small annual crops, arranged as seven-species multicrops and their corresponding monocrops, all under two contrasting watering regimes. We applied simple but robust statistical procedures to resulting data (based on bootstrap methods) to compare RMR, and its components, between different plants/plant parts. We also provide simple graphical tools to analyze the data.
Keywords： agroecosystem sustainability crop overyielding intercrop drought resistance overyield ecological
Title Author Date Type Operation
responses of soil organic carbon dynamics to nitrogen addition in different layers: a case study in an agroecosystem
Journal Article
FOR USE IN AGROECOSYSTEM IMPROVEMENT IN SEMI-ARID AREAS WITH A FOCUS ON CENTRAL ANATOLIA, TURKEY
Journal Article
Transmission of antibiotic resistance genes in agroecosystems: an overview
Jizheng HE, Zhenzhen YAN, Qinglin CHEN
Journal Article
CHARACTERISTICS OF SOIL QUALITY ATTRIBUTES UNDER DIFFERENT AGROECOSYSTEMS AND ITS IMPLICATIONS FOR AGRICULTURE IN THE CHOKE MOUNTAIN WATERSHED IN ETHIOPIA
Journal Article
京公网安备 11010502051620号
