Soil Quality Degradation Research Articles

Oxidative stress parameters, DNA damage and expression of HSP70 and MT in midgut of Trachyderma hispida (Forskål, 1775) (Coleoptera: Tenebrionidae) from a textile industry area

The textile mill industry is one of the major sources of pollution and contributors of metal contaminants to the environment. At the same time, the industry is important for global economy. Pollution caused by the textile industry is characteristic due to a unique set of potentially toxic substances. Darkling beetles (Coleoptera, Tenebrionidae), which live in all biogeographical regions, are especially common in soil quality and soil degradation studies. Our study was designed to assess long-term effects of textile industry (which generates specific pollution) on soil organisms, namely Trachyderma hispida. We especially wanted to find out what changes allow the species to survive and adapt to these specific conditions. Energy-dispersive X-ray spectroscopy of soil and midgut tissues of T. hispida sampled from a polluted site in the Edku textile industrial area in Egypt revealed a high accumulation of chemical elements, compared to a reference site. The concentration of elements in soil was well correlated with their concentration in the midgut of insects. Activity of superoxide dismutase, catalase, ascorbate peroxidase and glutathione S-transferase were negatively correlated with concentration of elements in soil and in the midgut. Meanwhile, malondialdehyde concentration in the midgut revealed an opposite tendency. DNA damage and expression of stress proteins, (HSP70 and metallothionein - MT) were elevated in insects from the polluted site. The activity of textile industry in the area of Edku undoubtedly causes an increase of soil pollution and, in consequence, causes a number of changes in the bodies of organisms living in these areas, including T. hispidus. Therefore, it is necessary to find a solution which limits the emission of waste from the textile industry, as well as to design modern strategies of processing, storing and utilizing it.

Soil acidification in moso bamboo (Phyllostachys edulis) forests and changes of soil metal ions (Cu, Pb) concentration

ABSTRACT Degradation of soil quality, especially soil acidification, restricts the sustainable management of moso bamboo forest. A 10-year pH monitoring study was carried out in Zhejiang Province, China. The soil acidification rate of moso bamboo forests was quantified by experiments. The results showed that the natural acidification rate of soil was 0.011 pH year−1. The average acidification rate of long-term application of nitrogen fertilizers reached 0.082 pH year−1, which was 7.5 times of that of non-fertilization control. Sequential chemical extraction for metals (Cu, Pb) revealed that the content of each fraction in fertilized soil was higher than that of the non-fertilization control. Potential mobility and bioavailability of metal ions (Cu, Pb) are greatly increased by soil acidification. The result of this research could provide valuable reference for nutrient management and sustainable management of moso bamboo forest. Attention should be paid to heavy metal pollution caused by the change of soil properties.

Field‐scale apparent soil electrical conductivity

AbstractSoils are notoriously spatially heterogeneous and many soil properties are temporally variable. Spatial variability of soil properties has a profound influence on agricultural and environmental processes, such as plant–water–soil interactions, water flow, and solute transport, resulting in within‐field plant yield variation and degradation of soil quality, to mention only a few. Field‐scale mapping of spatial variability and monitoring of temporally dynamic soil properties is necessary for a variety of edaphic activities, such as soil surveys, reclamation, crop selection, sitespecific management, and soil quality assessment. There are various approaches for characterizing soil spatial variability, but none of these has been as extensively investigated and is as reliable and cost effective as apparent soil electrical conductivity (ECa) directed soil sampling. Geospatial measurements of ECa are well suited for characterizing the spatial distribution of soil properties because they are reliable, quick, and easy to take with GPS‐based mobilized ECa measurement equipment. Directed soil sampling based on geo‐referenced measurements of ECa is a proven and robust means of characterizing the spatial variability of any soil property that influences ECa, including sol salinity, water content, texture, bulk density, organic matter, and cation exchange capacity. It is the goal of this methodology paper to provide an overview of the characterization of soil spatial variability across multiple scales using ECa–directed soil sampling with a focus on the field scale. Mobile ECa equipment, protocols, guidelines, special considerations, data reliability tests, and strengths and limitations are presented for characterizing spatial and temporal variation in soil properties using ECa–directed soil sampling.

Effect of lon 10.22271/phyto.2020.v9.i5ao.12791 g term zero tillage on soil organic carbon and its fractions: A review

Soil tillage disruption is a major cause of loss of organic matter and a decline in the number and stability of soil aggregates as natural habitats are transformed into agriculture. Compared to conventional tillage, zero tillage cropping systems typically demonstrate increased aggregation and soil organic matter. To feed the rising population on a sustainable basis without degrading natural resources, there is a need to increase farm productivity and total food production. Although the country's green revolution technologies implemented during 1966-67 led to food protection, intensive agriculture, insufficient and imbalanced use of fertilizers, high yielding crop varieties, the use of heavy machinery, excess tillage, etc., resulted in degradation of soil health and quality for more than five decades and increased pollution of air, soil and water. There is a great lack of a systematic approach to relating tillage practices to chemical soil properties. The most significant pillar of conservation farming is zero tillage. The need for an hour is conservation farming. It is a win-win operation for farmers as well as for the environment. The goal of Tillage was to establish a soil environment conducive to plant growth, but to have negative effects on soil resources, structure and eventually on the environment in the long run. Zero tillage has the ability to enhance the chemical properties and environment of the soil in the long run. Keeping all of these under consideration, this analysis is compiled to create a perfect tillage scheme, i.e. zero tillage, which eliminates the adverse effects of tillage and retains soil resources and eventually contributes to sustainable agriculture. The magnitude of changes in soil organic matter in response to zero tillage, however, differs between soils and the stabilisation mechanisms of organic matter in zero tillage systems.

Winter cover crops effects on soil microbial characteristics in sandy areas of Northern Shaanxi, China

ABSTRACT In sandy areas of Northern Shaanxi, after potato harvest, there are large areas of soil exposed to wind erosion from winter to spring, leading to degradation of soil quality. Planting cover crops in fallow fields is considered effective to improve soil biological properties; however, there is scarce study on the effect of winter cover crops on fallow soils in this region. In the study lasting from 2017 to 2019, four winter cover crops, i.e., alfalfa (AC), sweetclover (SC), winter [...]

Spatio-Temporal Distribution, Ecological Risk Assessment, and Multivariate Analysis of Heavy Metals in Bathinda District, Punjab, India

The pollution of agricultural soil due to heavy metals is a serious environmental problem throughout the world due to their persistence and toxicity. The present study was carried out on agricultural soils of district Bathinda, Punjab where a total of 120 soil samples were collected from 40 different locations during pre-monsoon, monsoon, and post-monsoon season. The total mean concentration of heavy metals (arsenic (As), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg), lead (Pb)) was estimated by ThermoScientific–iCAP Qc (Germany) inductively coupled plasma–mass spectrometry (ICP-MS). The concentration of heavy metals was of the order of Fe > Zn > Cr > Ni > Cu > Co > As > Pb > Hg > Cd, Fe > Zn > Cr > Ni > Cu > Co > As > Pb > Hg > Cd, and Fe > Zn > Cr > Ni > Cu > Co > Pb > As > Hg > Cd in pre-monsoon, monsoon, and post-monsoon seasons, respectively. The metals such as Fe, Zn, Cr, and Ni indicated higher concentrations at most of the sites, whereas Hg and Cd showed lower concentrations throughout the region. The total mean concentrations (mg/kg) of the metals were found to be lower than their natural background concentration values. Based on enrichment factor (EF), the soils were moderately contaminated at most of the sites with a few cases where the soil was minimally enriched with heavy metals. Other pollution indices such pollution load index (PLI) and degree of contamination (Cd) also indicated low to moderate level of soil contamination. Besides, risk assessment of heavy metals was also determined using potential ecological risk factor (Ei) and ecological risk index (Ri) which indicated low Ei and Ri in the region for most of the metals. Spatial distribution using interpolation technique, Inverse Distance Weighted (IDW) in ArcGIS 10.6.1 software, showed a significant spatial and seasonal variability of heavy metals throughout the region. Pearson’s correlation coefficient (r) between heavy metal variables was found to be significant at p < 0.05 significance level (As-Cr (r = 0.769), As-Fe (r = 0.760), As-Co (r = 0.883), As-Ni (r = 0.886), As-Cu (r = 0.859), As-Hg (r = 0.678) in pre-monsoon samples; As-Fe (r = 0.613), As-Co (r = 0.669), As-Ni (r = 0.619), As-Cu (r = 0.639) in monsoon samples and As-Cr (r = 0.631), As-Fe (r = 0.715), As-Co (r = 0.710), As-Cu (r = 0.690) in post-monsoon samples) indicated a strong relationship between different variables. Principal component analysis (PCA) technique also proved to be significant in studying the behavioral pattern of variables, where PCA biplots showed different behavior as revealed from some strong associations. Finally, continuous monitoring of the sites is suggested to avoid further contamination and degradation of soil quality, despite low contamination levels in the region.

Viability of Agroecological Systems under Climatic Uncertainty

To cope with ever-increasing demand and ensure food security, agronomic systems have shifted over time from traditional agriculture, based on the organic fertilization of soils, to intensive and specialized farming that use chemical fertilization. This resulted in increased soil productivity in the short term, but caused serious ecological drawbacks over time (degradation of soil quality, pollution of water and air, loss of biodiversity, erosion, etc.), and even reversed the trend of agricultural productivity. In this paper, we propose a viability theory–based model to study the sustainability of an agricultural system subject to climate uncertainty. Our objective is to determine what farming practices and activity sequences restore soil quality to a desired level while ensuring an acceptable level of productivity in the presence of the risk of major climatic disasters. The model is applied to Guadeloupe, an island in the West French Indies. We found that the results are highly sensitive to the direct effect of hurricanes on the soil’s quality, which, in turn, strongly affects the impact of the other parameters and that the export oriented sector is more vulnerable and less resilient to climatic uncertainties than the sector aimed at the local market.

Sentinel-2 red-edge spectral indices (RESI) suitability for mapping rubber boom in Luang Namtha Province, northern Lao PDR

Rubber (Hevea brasiliensis) tree cultivation is being continuously expanded northward by replacing evergreen forests and swidden-related regenerated vegetation across the uplands of mainland Southeast Asia (MSEA), e.g., Laos, a landlocked mountainous country. The non-native tree establishment in the northern tropical edge, or the non-traditional suitable planting area, provides stable supplies of natural latex, yet also leads to severe ecological degradation and environmental effects in water conservation, soil quality, rainforest fragmentation and biodiversity. Rubber plantations in the northern part of MSEA are normally characterized by periodic deciduous during the dry season, along with a lengthy defoliation-foliation duration, because of seasonal variations in temperature and precipitation. It thus lays a phenological and physiological base for dynamics monitoring with common multispectral (e.g., near-infrared and short-wave infrared bands) satellites, particularly Landsat. However, whether Sentinel-2 red-edge based algorithms are suitable for discriminating rubber plantations is not yet exclusively reported. Here, we developed a red-edge spectral indices (RESI) method through the normalization of three red-edge bands and applied it to identify and map rubber plantations in Luang Namtha Province of northern Laos, where a rubber boom begun in the mid-2000s. The RESI algorithm highlights the sensitivity of red-edge bands to the changes in moisture content and canopy density of rubber plantations. The area of mature rubber plantations was estimated to be 771.2 km2 in this province bordering southwest China in 2018, which was nearly twice as much as that of 2011, with the overall accuracy and kappa coefficient up to 92.50% and 0.91, respectively. Our phenology-based RESI approach not only indicates that Sentinel-2 imagery holds significant potential for monitoring rubber plantations, but also improves the remotely-sensed methods of rubber boom mapping via introducing the red-edge channel.

Improved pond productivity through integrated cultivation of red tilapia (Oreochromis niloticus), tiger shrimp (Penaeus monodon) and seaweed (Gracilaria verrucosa) in Maros, South Sulawesi, Indonesia

Marginal land use for brackish water aquaculture has not been fully used optimally, due to various problems, especially low pond productivity caused by degradation of water and soil quality. One effort to increase pond productivity for aquaculture is integrated cultivation (polyculture) with various fisheries commodities. The purpose of this research was to increase the productivity of ponds through polyculture of red tilapia, tiger shrimp, and seaweed. Twelve earthern ponds were used for this study, each pond of 2,500 m2 The nos polyculture systems employed in this study were A) red tilapia (1 no/m2), tiger shrimp (2 nos/m2) and seaweed (0,15 kg/m2); B) Tiger shrimp (4 nos/m2) and seaweed (0,15 kg/m2); C) red tilapia (1 no/m2) and tiger shrimp (2 nos/m2), and D) red tilapia (2 nos/m2) and seaweed (0,15 kg/m2). The results showed that the highest survival rate of red tilapia was recorded in D (87.3±3.15%) and the lowest in A (78.5±1.75%). Meanwhile, the highest tiger shrimp survival rate was achieved in B (72,2±6,53%) followed by A (64.0±3,02%) and C (62,6±3.15 %).The highest production of red tilapia was recorded in D (716.7 kg/2,500 m2), while the highest production of tiger shrimp was in B (100,04 kg/2,500 m2). The feed conversion ratio (FCR) in the red tilapia was the highest in D (1.19), followed by C and A (1.15 and 1.03), while the FCR for tiger shrimp in all the treatments was less than 1. Economic analysis showed that the highest profit per cycle was obtained in D.

Research advances on driving mechanism of nitrogen and phosphorus loss in sloping fields

Slope runoff and its associated soil nutrient loss are affected by precipitation, topography, underlying surface conditions and soil physical and chemical properties. The loss of nitrogen and phosphorus in slopes is an important cause of soil quality degradation and eutrophication of water bodies. Therefore, based on the study of rainfall runoff, the loss of soil nutrients and the change of runoff quality in the process of runoff can be further analyzed, which can provide reference for controlling nutrient loss and revealing the mechanism of nutrient loss. In this paper, the current situation of the study on the loss of nitrogen and phosphorus in sloping fields at home and abroad is analyzed from five aspects of precipitation, topography, soil characteristics, vegetation and human activities. The possible research directions in the future are put forward from three aspects of precipitation characteristics, topography and vegetation conditions, so as to provide ideas for more systematic study on the loss mechanism of nitrogen and phosphorus in sloping fields.

Factors of soil and atmospheric air degradation and their influence on the state of plants in urban and suburban ecosystems

This paper presents data on characteristics and extent of degradation of soil quality, atmospheric air and plants in urban and suburban areas of the Lower and Middle Volga region, Central Chernozem region. The goal of the research is to analyze and present data of environmental monitoring of soil, atmosphere and plants. On the example of the Saratov, Voronezh and Penza Regions, the values of the state of terrestrial ecosystems on different types of soils are established. The predominant position in terms of area and economic use is occupied by soils transformed in the course of urban development, as well as artificial soils. Compaction, anthropogenic inclusions, littering and heavy metal contamination are of great importance in the degradation of the soil cover. In the air-technogenic pollution, the formation and deposition of dust on the leaf surface of plants plays a significant role. Bioindicative signs in the analysis of the state of the environment and ecological systems were indicators of the viability, condition and stability of trees and shrubs. They are obtained based on average data from the research and subsequent assessment of life status. Separately, the indicators of degradation of woody plants assimilation organs depending on the levels of unfavorable soil-ecological and aerogenic conditions in urban and suburban ecosystems of the studied regions are considered. The significance of degradation of environmental objects by analyzed anthropotechnogenic factors is reflected in the correlation analysis results.

Low input sustainable agriculture: A viable climate-smart option for boosting food production in a warming world

Abstract Maximizing food production for feeding a rapidly growing human population while minimizing critical resource use and soil quality degradation is a major challenge for global sustainability. Sustainable agricultural practices based on low-external input is of paramount importance for reducing environmental trade-offs and planet healthy food production. Therefore, a critical assessment was made on viable low-input technologies aimed to reduce the negative effects of agricultural production as well as the use of various crop simulation models for forecasting the agricultural production under changing climatic scenario. While crop simulation models are helpful for predicting the growth and yield of individual crops under current as well as futuristic scenarios, it is difficult to model the response of multiple cropping systems under changing climatic conditions. As a matter of fact, the developing countries, majorly dependent on agriculture are most vulnerable to climate change. The increasing price of agrochemicals is another setback for subsistence farmers in resource-poor nations. In this backdrop, the current review aimed to assess the impact of climate change on agriculture, and the role of low input sustainable agriculture (LISA) for ensuring the food security while safeguarding the critical natural resources for human-wellbeing and also for attaining UN-Sustainable Development Goals. In addition, evidence-based impacts of LISA in emerging economies from Africa and South Asia are highlighted and suitable ecological indicators for measuring the sustainability of such LISA are addressed in brief. We conclude that the large-scale implementation of LISA will facilitate agricultural sustainability, and therefore, suitable policy frameworks are imperative for its worldwide adoption.

Dual benefits of long-term ecological agricultural engineering: Mitigation of nutrient losses and improvement of soil quality

Soil erosion of sloped farmland in the Three Gorges Reservoir area (TGRA) has led to the serious loss of nutrients, soil quality degradation and the downstream water quality being threatened. Thus, a series of ecological agricultural engineering measures was established in 2011, as a field experiment using citrus (navel orange) plants to reduce soil erosion, which was monitored from 2011 to 2018. These ecological agricultural engineering measures included three treatments: 1) citrus intercropped with white clover (WC), 2) citrus orchard land mulched with straw (SM) and 3) citrus intercropped with hemerocallis (Hemerocallis flava) contour hedgerows (CH). The conventional citrus orchard management was regarded as control (CK). The results show, that compared with CK, nutrient loss from the experiments were reduced by the following amounts: for nitrogen - WC (35.5%), SM (44.0%) and CH (52.0%); for phosphorus - WC (40.0%), SM (51.7%) and CH (58.3%). Therefore, the ecological agricultural engineering measures effectively mitigate the nutrient loss loads of the navel orange citrus gardens. The citrus intercropped with the hemerocallis hedgerows is the most effective measure for the control of nutrient loss. After 8 years of experiment, the soil quality represented by average soil quality index (SQI) in these three treatments, are significantly higher than that of the CK (and the beginning of the experiment). This is because the application of these measures prevented the loss of: soil organic matter, bulk density and total phosphorus. It is predicted that the soil qualities of these three treatments will remain in the range of soil grade II and I for the next 5 years but the soil quality of CK will decrease to soil quality grade II and III. These results show that ecological agricultural engineering measures are a long-term promising and feasible method to reduce soil erosion and enhance soil quality.

Effect of irrigation water quality on soil properties and infrared spectroscopic signatures

Aim of study: To study the effect of irrigation with medium-to-low-quality water on an olive farm that seems to be causing salinity and/or sodicity problems in soils, and the ability of infrared spectroscopy to detect this problem.Area of study: The study was conducted in an olive (Olea europaea L.) grove located in Guarromán (Jaen, Spain), on the boundary of the Sierra Morena Mountains and the Guadalquivir Depression.Material and methods: The olive farm is cultivated over two soil typologies, a calcareous area (carbonated) dominated by Regosols and a siliceous area with Leptosols. Typical soil physical and chemical parameters were determined, as well as near and mid infrared spectra were collected for analysis.Main results: Soil physical properties were affected by irrigation, with low infiltration rates and symptoms of structural degradation. Chemical properties were also altered, showing high pH, low amounts of organic carbon and N, and high sodium concentrations. These effects were stronger in the samples directly affected by the irrigation bulb, with the siliceous soils more affected than carbonated, probably due to the positive effect of the higher amounts of calcium in the latter. Using infrared spectroscopy, it was possible to discriminate the samples of this farm affected by sodicity from similar soil samples in Jaen province not affected.Research highlights: the use of medium-to-low quality irrigation water affected soil physical and chemical properties. Infrared spectroscopy could be useful for quick assessment of soil quality and soil degradation from salinity and sodicity.

Amendments with humified compost effectively sequester organic carbon in agricultural soils

AbstractPreventing degradation of soil quality and productivity entails development of sustainable practices to enhance soil organic matter. We followed soil organic carbon (OC) accumulation during 3 years long‐field experiments in two different Italian soils under conventional tillage (TRA), reduced tillage (MIN), green manure (GM) and two rates (low, CMPL, and, high, CMPH) of mature compost amendments. Despite soil textures differences, CMP additions enhanced in both field sites OC accumulation in either bulk soils or water‐stable aggregates (WSA), especially for CMPH, that was more pronounced than for MIN and GM. While the sum of OC in WSA showed an average retention of 80–90% of cumulative carbon added with compost, incorporated OC in WSA of MIN and GM reached only 26 and 55% of total carbon amended with fresh biomass for the light and heavy textured soils, respectively. Hence, MIN and GM accumulated SOC only up to the physical saturation limit dictated by soil texture, whereas CMP retained a larger additional SOC than TRA due to hydrophobic affinity among apolar domains progressively added to soil with humified compost. Nuclear magnetic resonance spectra of humus extracted after the first and third treatment year confirmed this behaviour. While no changes were observed in spectra for MIN and GM, humic extracts from CMP showed significantly larger content of apolar alkyl and aromatic moieties after the third experimental year. Our results suggest that soil amendment with well humified compost is an effective practice to sequester carbon into agricultural soils, besides improving their organic fertility.

Soil quality shapes the composition of microbial community stress response and core cell metabolism functional genes

The capacity for soils to perform vital functions, such as agricultural production, is dependent on numerous properties. Their simultaneous effect on soil biota is of interest to assess impacts of agricultural management. Using a soil quality index (SQI) based on a priori assumptions of eight soil physico-chemical properties that promote plant growth and microbial biomass, we sought to: 1) investigate the effect of land use on SQI; and 2) test a relationship between SQI and the composition of microbial functional genes. In 29 soils under four distinct land uses (cotton, wheat, pasture and native vegetation) gene composition was most distinct in cotton. The SQI followed the gradient cotton < wheat < native vegetation < pasture, with pasture significantly greater than other land uses. Of 67 functional gene markers, gradient boosted machine learning identified five genes that correlated strongly with SQI. These were stress response (oxyR and dnaJ), core carbon, nitrogen and sulfur metabolism (PTS-Glc-EIIA, glnH and sat, respectively). Nutrient cycling functional genes did not correlate with SQI. A structural equation model of the relationship between soil properties, SQI, and the aforementioned genes was used to visualise these interactions (root mean squared error of 0.1, R2 of 0.64 and p < 0.001). We conclude that certain land use practices improve or degrade soil quality relative to native vegetation, and SQI primarily correlates with microbial stress response and core metabolism. This demonstrates capacity for microbial communities to adapt to environmental stress while certain functions remain relatively resilient.

Conservation agriculture with drip irrigation: Effects on soil quality and crop yield in sub-Saharan Africa

The traditional agriculture production system in sub-Saharan Africa (SSA) caused significant soil erosion and degradation of soil quality. In addition, dependability of rainfall for irrigation needs limits the crop production. Advanced agricultural practices are thus needed at the local level to sustain the livelihood of smallholder farmers in the region. In this study, conservation agriculture (CA) practice with drip irrigation technology was compared (using field experiments and watershed modeling) with the traditional conventional tillage (CT) practice for its potential in improving soil quality and crop productivity in the region. Biophysical data were collected (2015 to 2017) from a total of 43 paired plots (CA and CT) at four study sites in SSA: Dangishita and Robit in Ethiopia, Yemu in Ghana, and Mkindo in Tanzania. The Agricultural Policy/Environmental eXtender (APEX) model was calibrated and validated with reasonable efficiency in simulating crop yields for both CA and CT practices; average PBIAS ≤±12% and ≤±11%, for CA and CT. The impact of the CA system on soil quality (soil carbon [C] and nitrogen [N]) was analyzed based on the well-tested model prediction results. The total C and N were increased under CA across the study sites on average by 6% and 4.1%, when compared to CT over the study period. Both the experiment and model prediction showed that crop yield was significantly improved by CA—on average 37.4% increases across the sites when compared to CT. Conservation agriculture with drip irrigation was an efficient local strategy to improve crop production in the region while enhancing the ecosystem.

Effects of combined conservation practices on soil and water quality in the Central Mississippi River Basin

Conventional cultivation of claypan soils leads to soil and water quality degradation because of high runoff and associated soil erosion. The Goodwater Creek Experimental Watershed, which is part of the USDA Agricultural Research Service Benchmark Conservation Effects Assessment Project, Watershed Assessment Studies, was established to address these issues. Plot studies have highlighted trade-offs between erosion control and herbicide or nutrient runoff. There is a need for long-term field-scale evaluation of combined practices that reduce sediment, nutrient, and herbicide losses by runoff. A 36 ha field located in Missouri was under a conventional corn (<i>Zea mays</i> L.)–soybean (<i>Glycine max</i> L.) system from 1993 to 2003 with fertilizer application and tillage prior to planting in the spring. A precision agriculture system defined by two main management zones was implemented from 2004 to 2014: wheat (<i>Triticum aestivum</i> L.) and soybean in 60% of the field, and corn and soybean in the remaining 40%. The system included no-till, cover crops, atrazine split-applications based on weed pressure, variable rates of nitrogen (N), and variable rates of fall-applied phosphorus (P). The objective of this study was to compare runoff water quality from the two management systems, based on flow and load duration curves, cumulative distribution functions, and conclusions from replicated plot studies. The precision agriculture system did not affect annual runoff, but it did increase the frequency of low flows. Sediment losses were reduced by 87% as a result of no-till and cover crops. Atrazine and P losses were lower than expected, despite the lack of incorporation into the soil. Atrazine losses were possibly lower because of the wheat area acting as a buffer, greater atrazine adsorption and retention in the field, and faster decay. Dissolved P losses as a fraction of applied remained the same, likely because of greater adsorption and lower runoff risk when applying P. Finally, nitrate-N (NO₃-N) losses decreased and resulted in an overall decrease of N losses despite a slight increase of ammonium-N (NH₄-N) losses. Explanations included a greater soil water content, a different timing of N applications, and N uptake by cover crops. Building on these successes, an aspirational management system is proposed to further improve on the performance and practicality of the precision agriculture system.

THE ANALYSIS OF SOILS POLLUTION WITH PETROCHEMICALS BY THE MEANS OF ELECTROMETRIC METHOD

Petroleum products are one of the most common components of chemical pollution of the environment. They represent a group of pollutants of extremely complex and diverse chemical composition, which complicates their detection and analysis in environmental components. Sources and consequences of soils pollution with petroleum products are considered in the paper, stating that it causes degradation of soil quality and failing to perform environmental functions. The comparative analysis of conventional testing methods of petroleum products in the soil demonstrates their common disadvantages – complicated equipment used or low accuracy of results. The change of electric soil properties under the influence of petroleum pollution is offered to be used as the basis of alternative testing method. The measurement of electrical resistance of soils, typical for the territory of Kyiv, with artificially created petroleum pollution was used to develop model dependencies between concentration of petrochemicals and resistance of pollutes soils. The pollution was modeled with market products – gasoline, diesel fuel and semi-synthetic oil. The soils involved in the research are soddy-podzolic, dark-gray podzolic, gray forest and alluvial. The analysis of the obtained results has demonstrated that major difference in polluted soils resistance is conditioned by the type of soil, but not the type of petrochemical in question. This enables the use of developed models to define the presence of petrochemicals in specific soils, but prevents the exact determination of the pollution composition. The proposed method was tested on real samples of soils taken at fuel filling stations. The comparison of the concentrations determined by electrometric and gravimetric method shows the sufficient reliability of the model dependancies developed, but they must be adapted to the specific soil properties, in particular soil texture, reaction and humidity.

Improving of Degraded Soil Quality for Ficus variegata Nursery Media by Adding Organic Matters and NPK Fertilizer

The availability of topsoil which is relatively fertile to use as seedling media is more and more limited so that the low nutrient degraded soil become alternative media for tree seedling nursery. The purpose of the research was to get the combination of degraded soil media mixture for nyawai (Ficus variegata) seedling media in nursery. The degraded soil collected in the heavy eroded soil in Rumpin Villages, Rumpin Sub District, Bogor. Completed random design with factorial was used to test the media mixture treatments and NPK fertilizer dosages on the growth of nyawai seedling. A pair of leaves seedlings was transplanted on 5 media treatments, i.e. top soil, degraded soil, degraded soil 70 % + compost 30 % (v:v), degraded soil 90 % + rice husk charcoal 10 % (v:v), and degraded soil 60 % + compost 30 % + rice husk charcoal 10 % (v/v). The dosage of NPK fertilizer was used as much: 0 g, 0.5 g polybag, and 1.0 g/polybag. The result showed that interaction of media and NPK fertilizer dosages was only affected on seedling biomass parameter. The interaction treatment of the mixture media of degraded soil 60 %, compost 30 % and rice husk charcoal 10 % could increase the growth of nyawai seedlings high by 30.60 % and fertilizer treatment of 1 g NPK could increase seedling biomass 6.21 g. The mixture media and fertilizing treatment by NPK 1 g can be alternative media on nyawai nursery.