Effects of farmland conversion on the stoichiometry of carbon, nitrogen, and phosphorus in soil aggregates on the Loess Plateau of China

Earthworm activity has become more important in the Loess Plateau, where hydrological processes are crucial for ecosystem sustainability. In this study, we conducted a laboratory microcosm experiment to determine the various burrowing activities of Eisenia fetida and their impact on the soil hydraulic properties in response to different levels of soil moisture (50%, 70%, 90% of field capacity) in two common soil types (loessial and Lou soil) obtained from the Loess Plateau. Burrowing activity of E. fetida increased with higher soil moisture and was greater in loessial than in Lou soil. Most burrowing activities occurred within the top 5 cm and decreased with increasing soil depth. Macropores and burrow branching, which are highly related to the earthworm burrowing, were more prevalent in wetter soil. Earthworms significantly altered the formation of large soil aggregates (AGL, diameter >2 mm) under different soil moistures and depths. Distinct earthworm burrowing activities, controlled by soil moisture, altered soil hydraulic properties. However, soil saturated hydraulic conductivity (Ks) showed little differences between different treatments due to the horizontal and high–branched burrows of E. fetida, although higher burrowing activities were found in wetter soil. Soil field capacity was highest in drier soil due to the less macropores and burrowing activities.

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Effect of vegetation type on microstructure of soil aggregates on the Loess Plateau, China

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2017.03.014 ◽

2017 ◽

Vol 242 ◽

pp. 1-8 ◽

Cited By ~ 34

Author(s):

Dong Zhao ◽

Mingxiang Xu ◽

Guobin Liu ◽

Luyang Ma ◽

Shengmin Zhang ◽

...

Keyword(s):

Loess Plateau ◽

Vegetation Type ◽

Soil Aggregates ◽

The Loess Plateau

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Effects of Vegetation Restoration on the Distribution of Nutrients, Glomalin-Related Soil Protein, and Enzyme Activity in Soil Aggregates on the Loess Plateau, China

Forests ◽

10.3390/f10090796 ◽

2019 ◽

Vol 10 (9) ◽

pp. 796 ◽

Cited By ~ 2

Author(s):

Leilei Qiao ◽

Yuanze Li ◽

Yahui Song ◽

Jiaying Zhai ◽

Yang Wu ◽

...

Keyword(s):

Enzyme Activity ◽

Loess Plateau ◽

Soil Enzymes ◽

Ecological Stoichiometry ◽

Soil Aggregates ◽

Soil Aggregate ◽

Vegetation Restoration ◽

The Loess Plateau ◽

Nutrient Metabolism ◽

Soil Protein

Research Highlights: Soil enzymes have a significant impact on the production of glomalin-related soil protein (GRSP), directly and indirectly affecting the nutrient metabolism balance, but there is little available information on ecological stoichiometry in soil aggregates. Background and Objectives: Vegetation restoration changes community structure and species composition in ecosystems, thus changing the physicochemical properties of soil. Soil aggregate is the most basic physical structure of the soil. Therefore, in order to understand dynamic changes in soil aggregate nutrients as vegetation restoration progresses, we set out to investigate the nutrient distribution and utilization in aggregates, and how enzymes respond to the nutrient changes in achieving a nutritional balance along successive stages of vegetation restoration. Materials and Methods: We collected and analyzed soil from plots representing six different stages of a vegetation restoration chronosequence (0, 30, 60, 100, 130, and 160 years) after farmland abandonment on the Loess Plateau, China. We investigated soil nutrient stoichiometry, GRSP, and enzyme stoichiometry in the different successional stages. Results: The results revealed that soil organic carbon, total nitrogen, enzyme activity, and GRSP increased with vegetation recovery age, but not total phosphorus, and not all enzymes reached their maximum in the climax forest community. The easily extractable GRSP/total GRSP ratio was the largest at the shrub community stage, indicating that glomalin degradation was the lowest at this stage. Ecological stoichiometry revealed N-limitation decreased and P-limitation increased with increasing vegetation restoration age. Soil enzymes had a significant impact on the GRSP production, directly and indirectly affecting nutrient metabolism balance. Conclusions: Further study of arbuscular mycorrhizal fungi to identify changes in their category and composition is needed for a better understanding of how soil enzymes affect their release of GRSP, in order to maintain a nutrient balance along successive stages of vegetation restoration.

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Effects of 15-year vegetation restoration on organic carbon in soil aggregates on the Loess Plateau, China

Archives of Agronomy and Soil Science ◽

10.1080/03650340.2021.1994952 ◽

2021 ◽

pp. 1-14

Author(s):

Peng Shi ◽

Mingxing Ren ◽

Peng Li ◽

Zhanbin Li ◽

Jingmei Sun ◽

...

Keyword(s):

Organic Carbon ◽

Loess Plateau ◽

Soil Aggregates ◽

Vegetation Restoration ◽

The Loess Plateau

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Effects of Different Land-Use Systems on Soil Aggregates: A Case Study of the Loess Plateau (Northern China)

Sustainability ◽

10.3390/su9081349 ◽

2017 ◽

Vol 9 (8) ◽

pp. 1349 ◽

Cited By ~ 12

Author(s):

Shahmir Kalhoro ◽

Xuexuan Xu ◽

Wenyuan Chen ◽

Rui Hua ◽

Sajjad Raza ◽

...

Keyword(s):

Land Use ◽

Loess Plateau ◽

Soil Aggregates ◽

Northern China ◽

The Loess Plateau ◽

Land Use Systems

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Shoot-soil ecological stoichiometry of alfalfa under nitrogen and phosphorus fertilization in the Loess Plateau

Scientific Reports ◽

10.1038/s41598-021-94472-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jiaoyun Lu ◽

Hong Tian ◽

Heshan Zhang ◽

Junbo Xiong ◽

Huimin Yang ◽

...

Keyword(s):

Loess Plateau ◽

Ecological Stoichiometry ◽

Effective Means ◽

Phosphorus Fertilization ◽

The Loess Plateau ◽

Nitrogen And Phosphorus ◽

Soil C ◽

Soil P ◽

P Limitation ◽

C And N

AbstractPlants and soil interactions greatly affect ecosystems processes and properties. Ecological stoichiometry is an effective means to explore the C, N, P correlation between plants and soil and the relationship between plant growth and nutrient supply. Serious soil erosion on China’s Loess Plateau has further barrenness the soil. Fertilization solves the problem of ecosystem degradation by improving soil fertility and regulating the ecological stoichiometric between soil and plants. No fertilization (CK), nitrogen fertilization (N), phosphorus fertilization (P) and N and P combined fertilization (NP) treatments were set in an alfalfa grassland. Organic carbon (C), nitrogen (N) and phosphorus (P) nutrients and their stoichiometry were measured in shoot and soil. P and NP fertilization increased shoot C concentration (3.12%, 0.91%), and all fertilization decreased shoot N concentration (6.96%). The variation of shoot C and N concentrations resulted in a greater increase in shoot C:N under the fertilization treatment than that under CK (8.24%). Most fertilization treatments increased shoot P concentration (4.63%) at each cut, which induced a decrease of shoot C:P. Shoot N:P of most treatments were greater than 23, but it was lower under N and NP fertilization than that under CK. Fertilization only increased soil C in 2014, but had no effect on soil N. Soil P content was significantly higher under P fertilization in 2014 (34.53%), and all fertilization in the second cut of 2015 (124.32%). Shoot and soil C:P and N:P having the opposite changes to shoot and soil P, respectively. Our results suggest that the change of P after fertilization largely drove the changes of stoichiometric. The growth of alfalfa in the Loess Plateau was severely restricted by P. It is an effective method to increase the biomass of alfalfa by increasing the addition of N or NP fertilizer to alleviate P limitation.

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Research on Anti-Scourability of Slope Eroded Soil

10.20944/preprints202105.0291.v1 ◽

2021 ◽

Author(s):

Liu Xin Chun ◽

Kang Yongde ◽

Chen Hong Na ◽

Lu Hui

Keyword(s):

Correlation Coefficient ◽

Loess Plateau ◽

Water Conservation ◽

Soil Aggregates ◽

P Value ◽

The Loess Plateau ◽

Exponential Relationship ◽

R Value ◽

Function Relationship ◽

D Value

Purpose - Soil aggregates are of great significance to soil and water conservation and ecological environment construction in arid area of northwest district．Methods - Exploring the effects of different vegetation includes types and land use methods on the stability of soil aggregates in the Loess Plateau, and provide reference for the rational use and management of land, also the improvement of soil structure in the region. Select 9 types of samples of 0-30 cm of typical soil plots as the research objects, compare and analyze the particle size index, stability differences and anti-erodibility of soil aggregates under various vegetation cover. Results - The results show that P value, MWD value, GMD value, D value, and AI value of the 0-10cm surface soil all show the maximum value. As the depth increases, the size distribution of the above index values of each soil sample in the 10-20cm and 20-30cm layers is different; P value in the 0-30cm depth layer is linearly positively correlated with the AI value and MWD value, and linearly negatively correlated with the D value. The correlation coefficient R between each variable is in the range of 0.78-0.97, and the D value reflects the Loess Plateau area stability and erosion resistance of soil aggregates better. GMD and MWD value show an exponential relationship, the correlation coefficient R value of 10-20cm height layer is 0.46; AI and MWD value in 0-10cm, 20-30cm height layer have a power function relationship, 10-20cm height layer has a polynomial function, the correlation coefficient R value is 0.97. The scour coefficient of different soil samples has a high degree of dispersion, the maximum CV value is 1.92, and the minimum value is 0.49. Conclusions - The results of this study can provide a theoretical basis for the ecological and hydrological benefit evaluation of slope erosion control and vegetation restoration on the Loess Plateau.

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