EFFECTS OF TILLAGE AND AMENDMENTS ON YIELDS AND SELECTED SOIL PROPERTIES OF TWO SOLONETZIC SOILS

1986 ◽  
Vol 66 (3) ◽  
pp. 455-470 ◽  
Author(s):  
G. R. WEBSTER ◽  
M. NYBORG
Keyword(s):  
Soil Properties ◽  
Negative Correlation ◽  
Soil Aggregates ◽  
Sodium Adsorption Ratio ◽  
The Other ◽  
Spring Season ◽  
Water Stable Aggregates ◽  
Mean Weight Diameter ◽  
Ap Horizon ◽  
Deep Plowing

Five tillage treatments in combination with two amendments and two crops were established on two Solonetzic sites and continued for 6 yr. Simulated deep plowing significantly [Formula: see text] reduced SAR values for the 0- to 15-cm depth (Ap horizon) to favorable levels of 3 to 5 at Site 1 but at Site 2 they remained in the 12 to 15 range. For the other four tillage treatments (simulated normal tillage, simulated shallow plowing, chiselling and chiselling plus simulated shallow plowing), the nonamended subplots at both sites had undesirably high SAR values in the 16 to 23 range. There was a trend for gypsum to lower SAR values of the 0- to 15-cm depth in most cases to the 10 to 15 range and was usually more effective than lime. For the 15- to 30-cm depth (Bnt) there was a trend for gypsum, and to a lesser degree lime, to lower SAR values from the 15 to 38 range to the 14 to 28 range 4 yr after the amendments had been applied. There was a negative correlation [Formula: see text] between SAR and soil aggregates < 6 mm in diameter and a positive correlation [Formula: see text] between SAR and soil clods in the 25- to 76-mm size. There was also a negative correlation [Formula: see text] between SAR and mean weight-diameter (water stable aggregates). Simulated deep plowing at Site 1 produced higher yields of alfalfa and barley than the other four tillage treatments [Formula: see text]. Alfalfa yields were considerably lower at Site 2 than at Site 1, but again simulated deep plowing produced the highest of all the tillage treatments. However, due to cloddiness of the seedbed at Site 2 in the simulated deep-plowed plots, germination of barley was poor for years when the spring season was dry. The chiselling treatment produced the highest yields of barley at this site. Gypsum, and to a lesser extent lime, lowered the SAR of the seedbed and improved aggregation but after 4 yr the 18 t ha−1 rate had only started to ameliorate the Bnt at both sites. Key words: Solonetzic soils, sodium adsorption ratio, soil aggregation, soil cloddiness

Short-term effects of grassland set-asides on soil properties in the Fraser River delta of British Columbia

2019 ◽  
Vol 99 (2) ◽  
pp. 136-145 ◽  
Author(s):  
Jason M. Lussier ◽  
Maja Krzic ◽  
Sean M. Smukler ◽  
Art A. Bomke ◽  
Drew Bondar
Keyword(s):  
Soil Properties ◽  
Bulk Density ◽  
Crop Production ◽  
Soil Aggregates ◽  
Negative Relationship ◽  
River Delta ◽  
Fraser River ◽  
Cost Share ◽  
Mean Weight Diameter ◽  
Fraser River Delta

Grassland set-asides (GLSA) in the Fraser River delta are fields that are taken out of crop production and seeded with a mixture of grasses and legumes for 1–4 yr. During this time, the farmer is compensated with a cost-share payment to recover a portion of the financial returns that could have been earned from cash crops. The objectives of this study were to (i) evaluate the effects of GLSA on soil properties during the initial two seasons of enrollment, (ii) determine how GLSA effects differ between fields that were considered productive and unproductive, and (iii) identify soil baseline indicators and preliminary soil thresholds for predicting GLSA vegetation responses. Out of eight fields entering the program, two were considered to be unproductive and exchangeable sodium had the strongest negative relationship to GLSA aboveground biomass (r = −0.61, P = 0.0002). During the second season of GLSA establishment, the mean weight diameter of water-stable soil aggregates was consistently higher in productive GLSAs than paired annual crop rotation (ACR) fields, being 21% higher in April, 14% in July, and 19% in September after crop harvest. After two seasons of GLSA enrollment, both aeration porosity and bulk density were improved by GLSA relative to ACR fields with aeration porosity being 24% greater and bulk density 7% lower in GLSA. The results suggest that GLSA rotations in productive agricultural fields within the Fraser River delta provide an alternative to continued ACR that can improve soil structure and reduce compaction after only two seasons of establishment.

EFFECT OF SOLONETZ SOIL HORIZON MIXING ON ALFALFA GROWTH

1970 ◽  
Vol 50 (3) ◽  
pp. 367-371 ◽  
Author(s):  
R. R. CAIRNS
Keyword(s):  
The Other ◽  
Soil Types ◽  
Soil Horizon ◽  
Infiltration Rates ◽  
Ap Horizon ◽  
Deep Plowing ◽  
Solonetz Soil

Samples of the Ap, Bn and Csk horizons of four Solonetz soil types were mixed to simulate the effect of deep plowing. Half of the mixed horizon samples were leached with water while the other half were not. Alfalfa was grown in the greenhouse on samples of Ap, Bn and mixed horizon soils. The alfalfa was harvested and chemically analyzed. The soil was subjected to certain chemical and physical determinations. Under conditions of adequate moisture the mixed horizons produced more alfalfa than the Ap horizon in two of the four soils. Leaching the mixtures resulted in lower alfalfa yields. Mixed horizon samples had higher infiltration rates, and lower breaking strengths than Bn horizon samples.

scholarly journals Exploring the use of spectral indices to assess alterations in soil properties in pine stands affected by crown fire in Spain

Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Cristina Fernández ◽  
José Mª Fernández-Alonso ◽  
José A. Vega ◽  
Teresa Fontúrbel ◽  
Rafael Llorens ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Soil Properties ◽  
Soil Aggregates ◽  
Burn Severity ◽  
Spectral Indices ◽  
Burned Areas ◽  
Mean Weight Diameter ◽  
Soil Burn Severity ◽  
Pine Stands ◽  
Changes In Soil Properties

Abstract Background Forest fires have increased in extent and intensity in the Mediterranean area in recent years, threatening forest ecosystems through loss of vegetation, changes in soil properties, and increased soil erosion rates, particularly in severely burned areas. However, establishing the relationships between burn severity and soil properties that determine infiltration remain challenging. Determining where soil burn severity evaluation should be carried out is critical for planning urgent measures to mitigate post-fire soil erosion. Although previous research has indicated that spectral indices are suitable for assessing fire severity, most of the classifications used consider combined effects in vegetation and soil. Moreover, the relationship between spectral indices and soil burn severity has scarcely been explored until now. Results We selected three pine stands in Spain for study immediately after being burned by wildfires. We analyzed various soil properties (soil saturated hydraulic conductivity, mean weight diameter of soil aggregates, and soil organic carbon) in relation to six levels of soil burn severity in all three stands. In addition, we established 25 field plots in the burned areas. We computed ten spectral indices for each plot by using Sentinel-2 satellite data. The soil burn severity categories indicated the degree of degradation of important soil properties related to soil erosion susceptibility. Of the spectral indices considered, the relativized burn ratio (RBR) was the best predictor of cumulative infiltration and mean weight diameter of soil aggregates. The differenced mid-infrared bispectral index (dMIRBI) was most closely correlated with soil organic carbon content. Conclusions The findings demonstrate the potential applicability of remote sensing to determining changes in soil properties after fire.

scholarly journals Growth of the tambaqui Colossoma macropomum (Cuvier) (Characiformes: Characidae): which is the best model?

2005 ◽  
Vol 65 (1) ◽  
pp. 129-139 ◽  
Author(s):  
M. A. H Penna ◽  
M. A Villacorta-Corrêa ◽  
T. Walter ◽  
M. Petrere-JR
Keyword(s):  
Growth Model ◽  
Negative Correlation ◽  
The Other ◽  
Data Sources ◽  
Von Bertalanffy ◽  
Data Set ◽  
Colossoma Macropomum ◽  
Von Bertalanffy Model ◽  
Estimated Parameters ◽  
Schnute Model

In order to decide which is the best growth model for the tambaqui Colossoma macropomum Cuvier, 1818, we utilized 249 and 256 length-at-age ring readings in otholiths and scales respectively, for the same sample of individuals. The Schnute model was utilized and it is concluded that the Von Bertalanffy model is the most adequate for these data, because it proved highly stable for the data set, and only slightly sensitive to the initial values of the estimated parameters. The phi' values estimated from five different data sources presented a CV = 4.78%. The numerical discrepancies between these values are of not much concern due to the high negative correlation between k and L<FONT FACE=Symbol>¥</FONT> viz, so that when one of them increases, the other decreases and the final result in phi' remains nearly unchanged.

Morpho-Biochemical Characteristics of Brinjal Germplasms Affect the Abundance And Infestation of Jassid

2021 ◽  
Vol 19 (1) ◽  
pp. 81-91
Author(s):  
F Yasmin ◽  
MR Amin ◽  
M Afroz ◽  
MAH Swapon ◽  
MM Hossain
Keyword(s):  
Protein Content ◽  
Chlorophyll Content ◽  
Negative Correlation ◽  
Significant Positive Correlation ◽  
Significant Negative Correlation ◽  
Reducing Sugar ◽  
Total Sugar ◽  
The Other ◽  
Biochemical Characteristics ◽  
Positive Correlation

The tropical vegetable, brinjal is cultivated throughout the year in Bangladesh but the crop is infested by a number of insects including jassid. This study investigated the effects of different biophysical and biochemical characteristics of twelve brinjal germplasms on the abundance and infestation of jassid. The experiment was conducted during September 2018 to March 2019 in Gazipur, Bangladesh with twelve brinjal germplasms namely BD-7320, BD-7328, BD-9952, BD-10154, BD-10158, BARI Begun-1, BARI Begun-4, BARI Begun-5, BARI Begun- 6, BARI Begun-7, BARI Begun-8 and BARI Begun-9. The incidence of jassid was recorded from 3rd December to 26th March, and the lowest population was found on BARI Begun- 6. Among the biophysical traits, plant height, number of branch and leaf per plant, and leaf area exerted significant positive correlation; whereas trichome on lower and upper surfaces of leaf, spine per stem and leaf showed significant negative correlation with the abundance of jassid. On the other hand, moisture, reducing sugar, total sugar and protein content of the leaves and fruits, chlorophyll content of the leaves exerts significant positive correlation but ash and pH contents of the leaves and fruits were negatively correlated with the abundance of jassid. Jassids showed the lowest level of leaf infestation on BARI Begun-6, which could be for further analysis to develop jassid resistant brinjal. SAARC J. Agric., 19(1): 81-91 (2021)

Cycles in symbol production? A new model to explain concentration, diversity and innovation in the music industry

Popular Music ◽  
1995 ◽  
Vol 14 (1) ◽  
pp. 55-93 ◽  
Author(s):  
Michael Christianen
Keyword(s):  
Negative Correlation ◽  
Music Industry ◽  
The Other ◽  
Recording Industry ◽  
Cultural Goods ◽  
New Model ◽  
Advantages And Disadvantages ◽  
Factors Influencing ◽  
Using Data ◽  
The One

With the publication of the article ‘Cycles in symbol production’ (Peterson and Berger 1975) a discussion started concerning the advantages and disadvantages of the production of cultural goods under market conditions. The analysis by Peterson and Berger showed a negative correlation between concentration in the recording industry, on the one hand, and the diversity and innovativeness of the music, on the other. Repetition of the analysis using data from the 1980s (Burnett 1990; Lopes 1992) has shown that for this period Peterson and Berger's hypotheses should be rejected. Is there a connection between concentration and diversity and innovation? Are there cycles in symbol production? There seems to be no conclusive answer. In this article, I will attempt to clear up this matter. First, I will repeat the analysis of the relation between concentration and diversity/innovation, using the same model as Peterson and Berger, but with different definitions for the variables concentration, diversity and innovation. Then I will suggest a new model, which can be helpful in uncovering other factors influencing diversity and innovation in the music industry. I will come to that later. Let me first give the reader a brief overview of previous research.

scholarly journals Analysis of the Effectiveness of E-Government in the Federal Government of Nigeria

2018 ◽  
Vol 8 (3) ◽  
pp. 75
Author(s):  
Robert A. Dibie ◽  
Maryam O. Quadri
Keyword(s):  
Social Media ◽  
Federal Government ◽  
Negative Correlation ◽  
Secondary Data ◽  
The Other ◽  
Government Relations ◽  
Professional Journals ◽  
Governance Practices ◽  
Government Websites ◽  
The Government

This paper examines the nature, impact, effectiveness and barriers of e-government in the Federal Government of Nigeria. It also explores the extent to which e-government has facilitated a better relationship between citizens and the federal government of Nigeria. It argues that the utilization of technologies such as internet, email, websites, and social media have yet to effectively connect citizens, and the government. As a result, the federal government of Nigeria has not fully adopted the new e-government approaches to improve its services. The paper uses data derived from questionnaire survey administered to 3,000 Nigerian citizens including federal government staff in Abuja, Lagos and some state capitals in Nigeria., Interviews of 300 federal officials and stakeholders were conducted. The secondary data consisted of the review of related government reports, government websites, academic and professional journals. Data were analyzed to determine the impacts of e-governance in the federal government. The conceptual framework is based on stakeholders’ theory, and an integrated e-government model. The findings suggest that on one hand there is a negative correlation between the e-governance initiatives and federal government efficient service delivery in Nigeria. On the other hand, there is also a negative correlation between citizens and federal government relations in the country. Some challenges preventing the adoption of proactive e-governance practices were identified and recommendations for appropriate policies that could address the current impediments were offered.

scholarly journals Multi-Decadal Trends and Variability in Temperature and Salinity in the Mid-Atlantic Bight, Georges Bank, and Gulf of Maine

2018 ◽  
Vol 76 (5) ◽  
pp. 163-215 ◽  
Author(s):  
Elizabeth J. Wallace ◽  
Lev B. Looney ◽  
Donglai Gong
Keyword(s):  
River Discharge ◽  
Gulf Of Maine ◽  
Winter Season ◽  
Hudson River ◽  
The Other ◽  
Georges Bank ◽  
Spring Season ◽  
Science Center ◽  
Other Hand ◽  
Decadal Scale

Increasing attention is being placed on the regional impact of climate change. This study focuses on the decadal scale variabilities of temperature and salinity in the Mid-Atlantic Bight (MAB), Georges Bank (GB), and Gulf of Maine (GOM) from 1977 to 2016 using hydrographic survey data from the National Oceanic and Atmospheric Administration (NOAA) Northeast Fisheries Science Center. The MAB (as defined by the shelf regions from Cape Hatteras to Cape Cod) experienced warming rates of 0.57 °C per decade during the Winter/Spring season (Jan–Apr) and 0.47 °C per decade during the Fall/Winter season (Sep–Dec). The GOM and GB, on the other hand, warmed at approximately half the rate of the MAB over the same time span (1977–2016). We found that rates of warming vary on decadal time scales. From 1977 to 1999, significant temperature increases (> 0.6 °C/decade) were found in the southern regions of the MAB during the Winter/Spring season. During the same period, significant freshening (stronger than– 0.2/decade) was found in GB and the northern regions of the MAB during the Winter/Spring and Summer seasons. From 1999 to 2016, on the other hand, we found no significant trends in temperature and few significant trends in salinity with the exceptions of some northern MAB regions showing significant salting. Interannual variability in shelf salinity can in part be attributed to river discharge variability in the Hudson River and Chesapeake Bay. However, decadal scale change in shelf salinity cannot be attributed to changes in river discharge as there were no significant decadal scale changes in river outflow. Variability in along-shelf freshwater transport and saline intrusions from offshore were the likely drivers of long-term changes in MAB shelf-salinity.

scholarly journals Which one to trust? Exploratory analysis on astrology, science and religiosity among students in Bucharest

2021 ◽  
Vol 19 (1) ◽  
pp. 117-133
Author(s):  
Dragoș Obreja
Keyword(s):  
University Students ◽  
Negative Correlation ◽  
Strong Correlation ◽  
Statistical Significance ◽  
The Other ◽  
Contemporary Society ◽  
Negative Relation ◽  
Probability Sample ◽  
And Mathematics ◽  
Moderate Positive Correlation

Confidence in astrology remains a visible phenomenon in contemporary society, and this is a constant topic of academic interest. A survey based on 512 valid questionnaires were obtained from a non-probability sample of university students from Bucharest, in order to observe possible statistical relations between confidence in astrology, confidence in sciences such as medicine and mathematics, but also fields such as astronomy and horoscope. On the other hand, several statements have been used to measure the level of religiosity. Notable is the moderate positive correlation obtained between astrology and astronomy, but also the strong correlation between astrology and horoscope (this last correlation was expected). Broadly speaking, it is observed that astrology correlates positively with the variables that constitute the ‘inward’ component of religiosity, while the ‘outward’ component shows a rather negative correlation, but which does not enjoy a similar statistical significance. Astronomy, like medicine, outlines negative relation with the level of religiosity. Instead, the correlations that involve trust in medicine have a negative and moderate value, in relation to religiosity. In conclusion, it is observed that the trust in “strong sciences” generates more prompt correlations compared to the trust in astrology, while further studies are needed to clarify the reasons for such uncertain correlations between astrology and religiosity.

scholarly journals Dwarfing effect of interstems on growth and yield components of mango

1969 ◽  
Vol 72 (4) ◽  
pp. 501-508
Author(s):  
Agripino Pérez ◽  
Arturo Cedeño-Maldonado ◽  
Ismael Reyes-Soto ◽  
Justo López
Keyword(s):  
Negative Correlation ◽  
Yield Components ◽  
Tree Size ◽  
The Other ◽  
Growth And Yield ◽  
Tree Age ◽  
Yield Efficiency

Studies were conducted at the Fortuna Substation for 10 years to determine the effect of 5 interstems on growth and yield components of 2 commercial mango varieties. The interstems did not significantly affect the rootstock diameter when Edward variety was the scion; however, they did with Palmer variety as scion at the 3- and 6-year stages only, Irwin interstem diameter at the 3-year stage for Edward and Palmer, and at the 6- and 9-year stages for Edward, was significantly thicker than that of the other interstems. Edward on Manzano Tetenené had the thinnest interstems. In the two varieties studied, the scion diameter was scarcely affected by the interstems at 3, 6 and 9 years after transplanting. Edward and Palmer grafted on Irwin as interstems had significantly lower scion/interstem ratios. The opposite was true when these varieties were grafted on Julie. Three years after planting, the smallest trees were those of Edward and Palmer grafted on Malda; 6 and 9 years after planting, those of Edward grafted on Malda and Manzano Tetenené. Yield efficiency decreased significantly with tree age and size. Thus, there was a negative correlation between these parameters. Edward produced significantly more fruits than Palmer at the 3-year-old stage. Edward as interstem grafted on Eldon produced significantly more fruits at the 3-, 6- and 9-year stages than when grafted on the other interstems. Palmer grafted on Eldon was significantly more precocious than when grafted on the other interstems. Malda and Manzano Tetenené as interstems significantly reduced tree size of Edward; Julie as interstem reduced the size of Palmer.

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