Geophysical estimation of shallow permafrost distribution and properties in an ice-wedge polygon-dominated Arctic tundra region

Shallow permafrost distribution and characteristics are important for predicting ecosystem feedbacks to a changing climate over decadal to century timescales because they can drive active layer deepening and land surface deformation, which in turn can significantly affect hydrologic and biogeochemical responses, including greenhouse gas dynamics. As part of the U.S. Department of Energy Next-Generation Ecosystem Experiments-Arctic, we have investigated shallow Arctic permafrost characteristics at a site in Barrow, Alaska, with the objective of improving our understanding of the spatial distribution of shallow permafrost, its associated properties, and its links with landscape microtopography. To meet this objective, we have acquired and integrated a variety of information, including electric resistance tomography data, frequency-domain electromagnetic induction data, laboratory core analysis, petrophysical studies, high-resolution digital surface models, and color mosaics inferred from kite-based landscape imaging. The results of our study provide a comprehensive and high-resolution examination of the distribution and nature of shallow permafrost in the Arctic tundra, including the estimation of ice content, porosity, and salinity. Among other results, porosity in the top 2 m varied between 85% (besides ice wedges) and 40%, and was negatively correlated with fluid salinity. Salinity directly influenced ice and unfrozen water content and indirectly influenced the soil organic matter content. A relatively continuous but depth-variable increase in salinity led to a partially unfrozen saline layer (cryopeg) located below the top of the permafrost. The cryopeg environment could lead to year-round microbial production of greenhouse gases. Results also indicated a covariability between topography and permafrost characteristics including ice-wedge and salinity distribution. In addition to providing insight about the Arctic ecosystem, through integration of lab-based petrophysical results with field data, this study also quantified the key controls on electric resistivity at this Arctic permafrost site, including salinity, porosity, water content, ice content, soil organic matter content, and lithologic properties.

Download Full-text

Soil Organic Matter Content and Volumetric Water Content Affect Indaziflam–Soil Bioavailability

Weed Science ◽

10.1614/ws-d-16-00039.1 ◽

2016 ◽

Vol 64 (4) ◽

pp. 757-765 ◽

Cited By ~ 2

Author(s):

Matthew D. Jeffries ◽

Travis W. Gannon

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Water Content ◽

Perennial Ryegrass ◽

Soil Depth ◽

Organic Matter Content ◽

Matter Content ◽

Volumetric Water Content ◽

Growth Data ◽

Soil Organic Matter Content

Indaziflam is a cellulose biosynthesis-inhibiting herbicide for annual weed control in various agricultural systems. Sporadic cases of unacceptable injury to desirable plants have been reported after indaziflam application, which may have been due to conditions favoring increased indaziflam–soil bioavailability. Research was conducted from 2013 to 2015 on a sandy soil to elucidate the effects of soil organic matter content (SOMC) and soil volumetric water content (SVWC) on indaziflam–soil bioavailability. Indaziflam was applied (50 or 100 g ha–1) at fall only, fall plus spring, and spring only timings to plots in a factorial arrangement of SOMC, pre–indaziflam application (PrIA) SVWC, and post–indaziflam application (PoIA) SVWC. After application, field soil cores were collected for a subsequent greenhouse bioassay experiment, where foliage mass reduction of perennial ryegrass seeded from 0 to 15 cm soil depth was used as an indicator of indaziflam–soil bioavailability throughout the profile. Significant edaphic effects were observed at 0 to 2.5, 2.5 to 5, and 5 to 7.5 cm depths, with increased bioavailability at low compared with high SOMC. Pre–indaziflam application SVWC did not affect bioavailability, whereas PoIA high SVWC increased indaziflam–soil bioavailability at 2.5 to 7.5 cm depth compared with PoIA low SVWC. Low SOMC–PoIA high SVWC decreased perennial ryegrass foliage mass 40 and 37% at 5 to 7.5 cm depth from cores collected 10 and 14 wk after treatment, respectively, whereas reductions from all other SOMC–PoIA SVWC combinations were < 12% and did not vary from each other. Pearson's correlation coefficients showed a moderate, positive relationship between perennial ryegrass mass reductions at 0 to 2.5, 2.5 to 5, 0 to 5, and 0 to 10 cm depths and hybrid bermudagrass cover reduction, which suggests conditions favoring increased indaziflam–soil bioavailability can adversely affect plant growth. Data from this research will aid land managers to use indaziflam effectively without adversely affecting growth of desirable species.

Download Full-text

Effect of Soil Organic Matter Content and Volumetric Water Content on ‘Tifway 419’ Hybrid Bermudagrass Growth Following Indaziflam Applications

Weed Technology ◽

10.1614/wt-d-15-00192.1 ◽

2016 ◽

Vol 30 (3) ◽

pp. 677-687 ◽

Cited By ~ 1

Author(s):

Matthew D. Jeffries ◽

Travis W. Gannon

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Water Content ◽

Organic Matter Content ◽

Field Research ◽

Soil Surface ◽

Matter Content ◽

Volumetric Water Content ◽

Soil Organic Matter Content ◽

Application Timing

Indaziflam is a cellulose biosynthesis–inhibiting herbicide for PRE annual weed control in turfgrass systems. Since indaziflam's 2010 U.S. registration, sporadic cases of hybrid bermudagrass injury have been reported; however, causes are not well understood. Field research was conducted from 2013 to 2015 on sandy soil to elucidate the effects of soil organic matter content (SOMC) and soil volumetric water content (SVWC) on plant growth following indaziflam application on established or root-compromised (5 cm long) hybrid bermudagrass. The effect of SOMC was evaluated at two levels, 1.4 (low) and 5.5% (high) w/w at the soil surface (0 to 2.5 cm depth), whereas SVWC was evaluated PRE (2 wk before) and POST (6 wk after) indaziflam application at two levels (low or high). Indaziflam was applied (50 or 100 g ai ha−1) at fall-only, fall-plus-spring, and spring-only timings. Regardless of application timing or SVWC, indaziflam applied at 50 g ha−1 to high SOMC did not cause > 10% visual cover reduction on established or root-compromised hybrid bermudagrass. Indaziflam applied to hybrid bermudagrass on low SOMC exacerbated adverse growth effects, most notably when root systems were compromised before application. Overall, PRE indaziflam application SVWC did not affect hybrid bermudagrass growth. Within low SOMC, low POST indaziflam application SVWC caused less visual hybrid bermudagrass cover reduction than did high POST indaziflam application SVWC, whereas both fall-plus-spring and spring-only application timings caused similarly greater reductions than fall-only indaziflam application. Data from this research will aid turfgrass managers to effectively use indaziflam without adversely affecting hybrid bermudagrass growth.

Download Full-text

Soil nitrogen supply of peat grasslands estimated by degree days and soil organic matter content

Nutrient Cycling in Agroecosystems ◽

10.1007/s10705-020-10071-z ◽

2020 ◽

Vol 117 (3) ◽

pp. 351-365

Author(s):

J. Pijlman ◽

G. Holshof ◽

W. van den Berg ◽

G. H. Ros ◽

J. W. Erisman ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Nitrogen ◽

Organic Matter Content ◽

Matter Content ◽

Nitrogen Supply ◽

Degree Days ◽

Soil Organic Matter Content ◽

Soil Nitrogen Supply

Download Full-text

Estimation of soil organic matter content based on CARS algorithm coupled with random forest

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2021.119823 ◽

2021 ◽

pp. 119823

Author(s):

Jinbao Liu ◽

Zhenyu Dong ◽

Junshi Xia ◽

Huanyuan Wang ◽

Tingting Meng ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Random Forest ◽

Organic Matter Content ◽

Matter Content ◽

Soil Organic Matter Content

Download Full-text

Effect of Clay, Soil Organic Matter, and Soil pH on Initial and Residual Weed Control with Flumioxazin

Agronomy ◽

10.3390/agronomy11071326 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1326

Author(s):

Calvin F. Glaspie ◽

Eric A. L. Jones ◽

Donald Penner ◽

John A. Pawlak ◽

Wesley J. Everman

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Weed Control ◽

Soil Ph ◽

Organic Matter Content ◽

Amaranthus Retroflexus ◽

Matter Content ◽

Weed Species ◽

Soil Organic Matter Content ◽

Field Soils

Greenhouse studies were conducted to evaluate the effects of soil organic matter content and soil pH on initial and residual weed control with flumioxazin by planting selected weed species in various lab-made and field soils. Initial control was determined by planting weed seeds into various lab-made and field soils treated with flumioxazin (71 g ha−1). Seeds of Echinochloa crus-galli (barnyard grass), Setaria faberi (giant foxtail), Amaranthus retroflexus (redroot pigweed), and Abutilon theophrasti (velvetleaf) were incorporated into the top 1.3 cm of each soil at a density of 100 seeds per pot, respectively. Emerged plants were counted and removed in both treated and non-treated pots two weeks after planting and each following week for six weeks. Flumioxazin control was evaluated by calculating percent emergence of weeds in treated soils compared to the emergence of weeds in non-treated soils. Clay content was not found to affect initial flumioxazin control of any tested weed species. Control of A. theophrasti, E. crus-galli, and S. faberi was reduced as soil organic matter content increased. The control of A. retroflexus was not affected by organic matter. Soil pH below 6 reduced flumioxazin control of A. theophrasti, and S. faberi but did not affect the control of A. retroflexus and E. crus-galli. Flumioxazin residual control was determined by planting selected weed species in various lab-made and field soils 0, 2, 4, 6, and 8 weeks after treatment. Eight weeks after treatment, flumioxazin gave 0% control of A. theophrasti and S. faberi in all soils tested. Control of A. retroflexus and Chenopodium album (common lambsquarters) was 100% for the duration of the experiment, except when soil organic matter content was greater than 3% or the soil pH 7. Eight weeks after treatment, 0% control was only observed for common A. retroflexus and C. album in organic soil (soil organic matter > 80%) or when soil pH was above 7. Control of A. theophrasti and S. faberi decreased as soil organic matter content and soil pH increased. Similar results were observed when comparing lab-made soils to field soils; however, differences in control were observed between lab-made organic matter soils and field organic matter soils. Results indicate that flumioxazin can provide control ranging from 75–100% for two to six weeks on common weed species.

Download Full-text

Assessment of Potato Farmland Soil Nutrient Based on MDS-SQI Model in the Loess Plateau

Sustainability ◽

10.3390/su13073957 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3957

Author(s):

Yingying Xing ◽

Ning Wang ◽

Xiaoli Niu ◽

Wenting Jiang ◽

Xiukang Wang

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Fertility ◽

Soil Quality ◽

Soil Nutrients ◽

Organic Matter Content ◽

Soil Nutrient ◽

Matter Content ◽

Soil Organic Matter Content ◽

Farmland Soil

Soil nutrients are essential nutrients provided by soil for plant growth. Most researchers focus on the coupling effect of nutrients with potato yield and quality. There are few studies on the evaluation of soil nutrients in potato fields. The purpose of this study is to investigate the soil nutrients of potato farmland and the soil vertical nutrient distributions, and then to provide a theoretical and experimental basis for the fertilizer management practices for potatoes in Loess Plateau. Eight physical and chemical soil indexes were selected in the study area, and 810 farmland soil samples from the potato agriculture product areas were analyzed in Northern Shaanxi. The paper established the minimum data set (MDS) for the quality diagnosis of the cultivated layer for farmland by principal component analysis (PCA), respectively, and furthermore, analyzed the soil nutrient characteristics of the cultivated layer adopted soil quality index (SQI). The results showed that the MDS on soil quality diagnosis of the cultivated layer for farmland soil included such indicators as the soil organic matter content, soil available potassium content, and soil available phosphorus content. The comprehensive index value of the soil quality was between 0.064 and 0.302. The SPSS average clustering process used to classify SQI was divided into three grades: class I (36.2%) was defined as suitable soil fertility (SQI < 0.122), class II (55.6%) was defined as moderate soil fertility (0.122 < SQI < 0.18), and class III (8.2%) was defined as poor soil fertility (SQI > 0.186). The comprehensive quality of the potato farmland soils was generally low. The proportion of soil nutrients in the SQI composition ranged from large to small as the soil available potassium content = soil available phosphorus content > soil organic matter content, which became the limiting factor of the soil organic matter content in this area. This study revolves around the 0 to 60 cm soil layer; the soil fertility decreased gradually with the soil depth, and had significant differences between the respective soil layers. In order to improve the soil nutrient accumulation and potato yield in potato farmland in northern Shaanxi, it is suggested to increase the fertilization depth (20 to 40 cm) and further study the ratio of nitrogen, phosphorus, and potassium fertilizer.

Download Full-text