scholarly journals Small Scale Spatial Variability of Apparent Electrical Conductivity within a Paddy Field

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
W. Aimrun ◽  
M. S. M. Amin ◽  
M. H. Ezrin
Keyword(s):  
Electrical Conductivity ◽  
Paddy Field ◽  
Seasonal Variability ◽  
Management Practices ◽  
Exchange Capacity ◽  
Small Scale ◽  
Soil Features ◽  
Zone Management ◽  
Central Regions ◽  
Water Holding

Quick variability description is an important component for zone management practices. Precision farming requires topping up of only the nutrients that are lacking in the soil to attain the highest yield with the least input. The apparent soil electrical conductivity (ECa) sensor is a useful tool in mapping to identify areas of contrasting soil properties. In nonsaline soils,ECais a substitute measurement for soil texture. It is directly related to both water holding capacity and Cation Exchange Capacity (CEC), which are key ingredients of productivity. This sensor measures theECaacross a field quickly and gives detailed soil features (one-second interval) with few operators. Hence, a dense sampling is possible and therefore a high-resolutionECamap can be produced. This study aims to characterize the variability of soilECawithin a Malaysian paddy field with respect to the spatial and seasonal variability. The study was conducted at Block C, Sawah Sempadan, Selangor, Malaysia, for three continuous seasons. SoilECawas collected after harvesting period. The results showed that deepECavisualized the pattern of the former river routes clearly as continuous lines (about 45 m width) at the northern and central regions of the study area. This exploration has shown different maps with higher contrast as compared to the existing soil series map for the study area. Seasonal variability test showed that theECathat was acquired during rainy season (collected after harvest in December to January) has the highest value as compared to another season.

scholarly journals Quantifying Mechanistic Detachment Parameters Due to Humic Acids in Biological Soil Crusts

Land ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1180
Author(s):  
Atheer A. Abbood ◽  
Abdul-Sahib T. Al-Madhhachi
Keyword(s):  
Electrical Conductivity ◽  
Organic Matter ◽  
Humic Acid ◽  
Biological Soil Crusts ◽  
Exchange Capacity ◽  
Scale Model ◽  
Small Scale ◽  
Soil Erodibility ◽  
Soil Crusts ◽  
Detachment Rate

Humic acid (HA) is a material that could be used to decrease erosion and improve soil structure. It is also known that biological soil crusts (biocrusts) have a major role in soil stabilization, but the mechanism is not well understood in the presence of HA, especially with mechanistic soil detachment rate parameters (b0 and b1) of the Wilson model, where b0 is the dimensional soil detachment parameter and b1 is the dimensional soil threshold parameter. Therefore, this study intends to (1) investigate the effect of different humic acid (HA) concentrations (0%, 4%, and 8%) on mechanistic soil detachment rate parameters (b0 and b1,) in the Tigris Riversides of the Gheraiat region, Baghdad City, Iraq, of the crusted versus uncrusted soils using a small scale model of the jet erosion tests (mini-JET) at different curing periods (1 week, 2 weeks, and 3 weeks), and (2) examine the impact of HA on b0 and b1 parameters versus some soil characteristics, such as electrical conductivity, cation exchange capacity, and soil organic matter for uncrusted and crusted soils. Thirty-six undisturbed soil specimens (18 for crusted soils and 18 for uncrusted soils) were acquired from the Tigris Riverbank. On these specimens, the mini-JET was used to determine the mechanistic cohesive soil erodibility parameters b0 and b1. The results showed that the value of b0 decreased up to 60% with an increase in curing times for crusted soils until they reached their optimum values at 2 weeks. There was no consistent pattern for b1 at different curing times. As the concentration of HA increased, the value of b0 decreased up to 86% and 99% for crusted and uncrusted soils, respectively. HA significantly improved electrical conductivity, exchange capacity, and organic matter in the soil and reduced soil erodibility. This study provides the benefits of adding HA to the soils as a soil stabilizer using a low-cost technique, which is the JET instrument.

Some aspects of Sphagnum ecology

1986 ◽  
Vol 64 (2) ◽  
pp. 416-426 ◽  
Author(s):  
Richard E. Andrus
Keyword(s):  
Desiccation Tolerance ◽  
Cation Exchange Capacity ◽  
Environmental Gradients ◽  
Exchange Capacity ◽  
Small Scale ◽  
Desiccation Resistance ◽  
Photosynthetic Response ◽  
Drying Rates ◽  
Water Holding ◽  
Water Contents

Sphagnum species are ecologically prominent wetland plants with xerophytic adaptations and succession-directing acidification capabilities. Species are organized along environmental gradients of pH, cation concentrations, hummock and hollow, wet versus dry, shade versus sun, coastal versus inland, and cold versus warm. The known factors responsible for this organization include cation-exchange capacity, desiccation tolerance, desiccation resistance, water-holding capacity, drying rates, and photosynthetic response at differing water contents. Small-scale distribution of Sphagnum species can be better explained for ombrotrophic sites than for minerotrophic sites.

scholarly journals Irreversible sorption of carbofuran by moderately acidic soil amended with biochar

2020 ◽  
Vol 10 (2) ◽  
pp. 5224-5228
Keyword(s):  
Electrical Conductivity ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Dry Matter ◽  
Agricultural Waste ◽  
Exchange Capacity ◽  
Water Holding Capacity ◽  
Dry Matter Production ◽  
Matter Production ◽  
Water Holding

An ecofriendly technique to on farm burning of biomass by making biochar from agricultural waste was provided. Characteristic studies of biomass and biochar such as SEM, Ultimate and proximate analysis, pH, Cation exchange capacity, Water holding capacity, Electrical conductivity, Soil organic matter and Dry matter production were examined. Adsorption and desorption of carbofuran in soil were studied in batch experiment mode. From the experimental studies, it was observed that pH, Cation exchange capacity, Water holding capacity, Electrical Conductivity, Soil organic content and dry matter production increases with biochar addition. Adsorption Studies show that carbofuran adsorbed with control is 0.45 mg/g whereas with 3%BC it was 6.375 mg/g and desorption studies show that with 3% biochar carbofuran desorption is less. Hence Capsicum Annuam Biochar could be one of the promising option for improving the soil health as well as for adsorbing the pesticides.

scholarly journals Soil Quality of a Rice Organic Farm in Langkong, M'lang, Cotabato

2019 ◽  
Vol 24 (1) ◽  
pp. 35-53
Author(s):  
Kathleen Cedeño
Keyword(s):  
Organic Matter ◽  
Soil Fertility ◽  
Cation Exchange ◽  
Soil Quality ◽  
Cation Exchange Capacity ◽  
Management Practices ◽  
Exchange Capacity ◽  
Water Holding Capacity ◽  
Water Holding

Soil quality is crucial to global food production security. However, research data on soil quality, which is vital to enhancing soil fertility and crop yield, is limited particularly on the soil in the rice fields located in Langkong, Mlang, Cotabato. This study aims to assess the soil quality of one of the organic rice farms in said area. Soil samples were collected in thirty-one (31) paddies for two sampling periods: thirty (30) days after harvest and thirty (30) days after rice transplanting. Eight (8) soil indicators representing soil physicochemical characteristics were measured from 0-15 cm depth; the indicators were soil texture, water holding capacity, pH, exchangeable phosphorus, extractable potassium, total organic matter, electrical conductivity, and cation exchange capacity. Results reveal that soils in the studied area are characterized by clay loam with moderate water-holding capacity of about 62.57% and 60.57% for both sampling periods, respectively. The soil is strongly acidic (5.3 and 5.5) and has a low amount of organic matter (2.16% and 1.57%) and exchangeable P (8.55 ppm and 2.48 ppm), although it has marginal extractable K (80.77 ppm and 91.10 ppm). Also, the soils are non-saline and have low cation exchange capacity. The findings signify that the soils have insufficient fertility to sustain the optimal growth of the rice plants which can potentially reduce the yield of rice production. Thus, amendment of the soil quality and enhancement of soil management practices should be taken into consideration to further improve soil fertility to ensure productivity and profitability of farmers.

Concrete Grinding Residue: Management Practices and Reuse for Soil Stabilization

2019 ◽  
Vol 2673 (11) ◽  
pp. 748-763
Author(s):  
Bo Yang ◽  
Yang Zhang ◽  
Bora Cetin ◽  
Halil Ceylan
Keyword(s):  
Electrical Conductivity ◽  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Management Practices ◽  
Soil Stabilization ◽  
Cooling Water ◽  
Exchange Capacity ◽  
Residue Management ◽  
Unit Weight ◽  
State Regulations

Concrete grinding residue (CGR) is a slurry byproduct produced from diamond grinding operations used to smooth concrete pavement surface. As a waste material, CGR consists of cooling water for blades and concrete fines from the removed concrete layer. Since the composition of CGR reflects high pH, it can be a critical environmental issue and should be managed properly to reduce its impact to the ecological system. To understand the current management practices of CGR throughout the U.S.A., a comprehensive review of state regulations and a survey of departments of transportation and contractors were conducted in this study, with results showing that in many states detailed guidance for disposal of CGR to reduce risks was lacking. In addition, this study investigated the potential use of CGR for roadbed soil stabilization. To evaluate the performance of CGR for soil stabilization purpose, this study mixed 10%, 20%, 30%, and 40% of CGR by weight with two types of soils classified as A-4 and A-6 according to AASHTO. Unconfined compressive strength and California bearing ratio, pH, electrical conductivity, alkalinity, and cation-exchange capacity tests were conducted on specimens. Results of the strength tests showed that the soils treated with 20% of CGR had the highest strength. Other laboratory tests revealed that CGR treatment could reduce the maximum dry unit weight (γdmax) and plasticity and increase the pH, alkalinity, electrical conductivity and cation-exchange capacity of soils.

Impact Of Human Resource Practices In Small Scale Industries In Thoothukudi District Of Tamilnadu

2019 ◽  
Vol 5 (4) ◽  
pp. 160-169
Author(s):  
Srimo Fernandas
Keyword(s):  
Economic Growth ◽  
Human Resource ◽  
Management Practices ◽  
Human Factor ◽  
Vital Role ◽  
Small Scale ◽  
Average Income ◽  
Small Scale Industry ◽  
Human Resource Management Practices ◽  
Small Scale Industries

In the economic growth of a country, the human factor plays a vital role. The study has been made to study the growth of small scale industries in the development of human resource management practices of in Thoothukudi district. The study has the following objectives. To study the socio-economic outline of the small scale industry owners. To understand the nature of management of the small-scale industry. To find out the motivational factors for starting small-scale industries. To analyse the average income generated by different activities by the small scale industry owners.

scholarly journals Effect of Low Zeolite Doses on Plants and Soil Physicochemical Properties

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2617
Author(s):  
Alicja Szatanik-Kloc ◽  
Justyna Szerement ◽  
Agnieszka Adamczuk ◽  
Grzegorz Józefaciuk
Keyword(s):  
Plant Growth ◽  
Physicochemical Properties ◽  
Cation Exchange ◽  
Surface Area ◽  
Cation Exchange Capacity ◽  
N Fertilization ◽  
Exchange Capacity ◽  
First Year ◽  
Soil Physicochemical Properties ◽  
Water Holding

Thousands of tons of zeolitic materials are used yearly as soil conditioners and components of slow-release fertilizers. A positive influence of application of zeolites on plant growth has been frequently observed. Because zeolites have extremely large cation exchange capacity, surface area, porosity and water holding capacity, a paradigm has aroused that increasing plant growth is caused by a long-lasting improvement of soil physicochemical properties by zeolites. In the first year of our field experiment performed on a poor soil with zeolite rates from 1 to 8 t/ha and N fertilization, an increase in spring wheat yield was observed. Any effect on soil cation exchange capacity (CEC), surface area (S), pH-dependent surface charge (Qv), mesoporosity, water holding capacity and plant available water (PAW) was noted. This positive effect of zeolite on plants could be due to extra nutrients supplied by the mineral (primarily potassium—1 ton of the studied zeolite contained around 15 kg of exchangeable potassium). In the second year of the experiment (NPK treatment on previously zeolitized soil), the zeolite presence did not impact plant yield. No long-term effect of the zeolite on plants was observed in the third year after soil zeolitization, when, as in the first year, only N fertilization was applied. That there were no significant changes in the above-mentioned physicochemical properties of the field soil after the addition of zeolite was most likely due to high dilution of the mineral in the soil (8 t/ha zeolite is only ~0.35% of the soil mass in the root zone). To determine how much zeolite is needed to improve soil physicochemical properties, much higher zeolite rates than those applied in the field were studied in the laboratory. The latter studies showed that CEC and S increased proportionally to the zeolite percentage in the soil. The Qv of the zeolite was lower than that of the soil, so a decrease in soil variable charge was observed due to zeolite addition. Surprisingly, a slight increase in PAW, even at the largest zeolite dose (from 9.5% for the control soil to 13% for a mixture of 40 g zeolite and 100 g soil), was observed. It resulted from small alterations of the soil macrostructure: although the input of small zeolite pores was seen in pore size distributions, the larger pores responsible for the storage of PAW were almost not affected by the zeolite addition.

Sediment transport modifications induced by submerged artificial reef systems: a case study for the Gulf of Venice

2014 ◽  
Vol 43 (1) ◽  
Author(s):  
Davide Bonaldo ◽  
Alvise Benetazzo ◽  
Andrea Bergamasco ◽  
Francesco Falcieri ◽  
Sandro Carniel ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Coastal Zone Management ◽  
Artificial Reef ◽  
Sediment Concentration ◽  
Quantitative Information ◽  
Small Scale ◽  
Zone Management ◽  
Basin Scale ◽  
Scale Modelling ◽  
Maritime Spatial Planning

AbstractThe shallow, gently sloping, sandy-silty seabed of the Venetian coast (Italy) is studded by a number of outcropping rocky systems of different size encouraging the development of peculiar zoobenthic biocenoses with considerably higher biodiversity indexes compared to neighbouring areas. In order to protect and enhance the growth of settling communities, artificial monolithic reefs were deployed close to the most important formations, providing further nesting sites and mechanical hindrance to illegal trawl fishing.In this framework, a multi-step and multi-scale numerical modelling activity was carried out to predict the perturbations induced by the presence of artificial structures on sediment transport over the outcroppings and their implications on turbidity and water quality. After having characterized wave and current circulation climate at the sub-basin scale over a reference year, a set of small scale simulations was carried out to describe the effects of a single monolith under different geometries and hydrodynamic forcings, encompassing the conditions likely occurring at the study sites. A dedicated tool was then developed to compose the information contained in the small-scale database into realistic deployment configurations, and applied in four protected outcroppings identified as test sites. With reference to these cases, under current meteomarine climate the application highlighted a small and localised increase in suspended sediment concentration, suggesting that the implemented deployment strategy is not likely to produce harmful effects on turbidity close to the outcroppings.In a broader context, the activity is oriented at the tuning of a flexible instrument for supporting the decision-making process in benthic environments of outstanding environmental relevance, especially in the Integrated Coastal Zone Management or Maritime Spatial Planning applications. The dissemination of sub-basin scale modelling results via the THREDDS Data Server, together with an user-friendly software for composing single-monolith runs and a graphical interface for exploring the available data, significantly improves the quantitative information collection and sharing among scientists, stakeholders and policy-makers.

scholarly journals Applying Nitrogen Site-Specifically Using Soil Electrical Conductivity Maps and Precision Agriculture Technology

2001 ◽  
Vol 1 ◽  
pp. 767-776 ◽  
Author(s):  
E.D. Lund ◽  
M.C. Wolcott ◽  
G.P. Hanson
Keyword(s):  
Electrical Conductivity ◽  
Case Studies ◽  
Crop Yield ◽  
Soil Texture ◽  
Precision Agriculture ◽  
Management Practices ◽  
N Availability ◽  
Soil Electrical Conductivity ◽  
Variable Yield ◽  
Wide Range

Soil texture varies significantly within many agricultural fields. The physical properties of soil, such as soil texture, have a direct effect on water holding capacity, cation exchange capacity, crop yield, production capability, and nitrogen (N) loss variations within a field. In short, mobile nutrients are used, lost, and stored differently as soil textures vary. A uniform application of N to varying soils results in a wide range of N availability to the crop. N applied in excess of crop usage results in a waste of the grower’s input expense, a potential negative effect on the environment, and in some crops a reduction of crop quality, yield, and harvestability. Inadequate N levels represent a lost opportunity for crop yield and profit. The global positioning system (GPS)-referenced mapping of bulk soil electrical conductivity (EC) has been shown to serve as an effective proxy for soil texture and other soil properties. Soils with a high clay content conduct more electricity than coarser textured soils, which results in higher EC values. This paper will describe the EC mapping process and provide case studies of site-specific N applications based on EC maps. Results of these case studies suggest that N can be managed site-specifically using a variety of management practices, including soil sampling, variable yield goals, and cropping history.

Sign in / Sign up

Export Citation Format

Share Document