Buffering Capacities in Mediterranean soils under different soil management

<p>Dryland areas are being seriously affected by degradation processes. The use of organic amendments in ecosystem restoration is an effective technique for accelerating soil regeneration processes in degraded drylands. The goal of this paper is to establish the effect of application of various organic amendments to degraded soil, on soil buffering capacity after 10 years. Buffering capacity is an important indicator, which is evidence of the overall condition of the soil ecosystem and influences a whole range of other soil properties, because buffering in soil is defined as the resistance of the soil to variations in pH. The experiment was carried out at the location called El Pinarillo in the Sierra de Tejeda, Almijara and Alhama Natural Park (southern Spain). The site is located at 470 m a.s.l., in the upper part of an alluvial fan (calcareous conglomerates). The experiment treatments were natural soil, bare soil, hydropolymers, pinus mulch, prescribed burnt, Sewage sludge. Application of hydrogel had the smallest effect on buffering capacity 10 years after application and manifested as just a slight decrease in soil buffering capacity while maintaining or improving other soil properties. The good buffering capacity of this variant also allows further work with the specific soil without greater risk of further degradation. Sludge was identified as the worst variant, whereas soil buffering capacity fell markedly, because sewage sludge may significantly inhibit microbial activity and decomposition of organic matter. This variant is not suitable for further use, because there is a risk of further soil degradation.</p>

Nitrogen, Phosphorus, and Potassium Adsorption and Desorption Improvement and Soil Buffering Capacity Using Clinoptilolite Zeolite

The physical and chemical properties of clinoptilolite zeolite can be used to enhance soil nutrient availability for optimum crop use. Amending nitrogen, phosphorus, and potassium fertilizers with clinoptilolite zeolite could create a pool of negative charges to retain and release nutrients timely for crop use. Thus, we used clinoptilolite zeolite to enhance Typic Paleudults sorption (adsorption and desorption) of nitrogen, phosphorus, potassium, and this soil’s pH buffering capacity. The treatments evaluated were: (i) 250 g soil alone, (ii) 20 g clinoptilolite zeolite alone, (iii) 250 g soil + 20 g clinoptilolite zeolite, (iv) 250 g soil + 40 g clinoptilolite zeolite, and (v) 250 g soil + 60 g clinoptilolite zeolite. Clinoptilolite zeolite increased soil nitrogen and potassium adsorption, nitrogen desorption, and soil pH. Moreover, ability of the soil to resist drastic change in pH (pH buffering capacity) was improved. Additionally, phosphorus adsorption and desorption of phosphorus and potassium were reduced. Higher potassium adsorption with lower potassium desorption suggests that the clinoptilolite zeolite sorbs potassium effectively. The clinoptilolite zeolite nitrogen, phosphorus, and potassium contributed to the reduction in the adsorption these nutrients. The clinoptilolite zeolite improved nitrogen, phosphorus, and potassium availability and soil buffering capacity to prevent these nutrients from being fixed or lost through for example, leaching. Therefore, clinoptilolite zeolite application could contribute to improved use of nitrogen, phosphorus, and potassium fertilizers to prevent soil, air, and water pollution. Additionally, our intervention could improve nitrogen, phosphorus, and potassium use efficiency.

The Effect of Biohumus on Increasing of the Fertility Gray-Brown Soils in Mountainous Shirvan

The introduction of biohumus into degraded gray-brown soils contributed to the improvement of their agrophysical and agrochemical properties. The density of the arable horizon has decreased by 0.02–0.16 g/cm3, the content of water-resistant aggregates, providing an optimal water-air regime, has doubled. The introduction of biohumus can solve the problem of soil overconsolidation. The research results show that when biohumus is introduced into gray-brown soils in an amount of 3.0, 4.0 and 5.0 m/ha, certain changes occur in the humus content according to its introduction, that is, an increase in the humus content in the arable soil layer compared to with the control option was −0.33, 0.51 and 0.62%. Regular use of biohumus will allow to suspend the process of soil dehumification and improve the conditions of the humus state of the soil, as well as the mineral nutrition of plants, leads to an increase in total nitrogen, mobile forms of phosphorus and potassium, which participate and contribute to an increase in soil buffering and prevent the entry of toxic substances into plants.

Zone of Technogenic Pollution of the Pervouralsk-Revda Industrial Hub: Soil Assessment and Land Use Issues

The influence of heavy metals pollution of soils and lands in the zone of metallurgical plants influence in the Sverdlovsk region (Russia) was analyzed. Sredneuralsk Copper Smelting Plant (SUMZ) is an environmental polluter with copper, lead, zinc, cadmium and sulfur oxides, nitrogen and hydrogen fluoride. Pervouralsk plant for production of chromium-containing materials ("Crompick") generates emissions of chromium compounds and other heavy metals. Environmental risk was assessed using the Zc pollution index adopted by the Russian regulations and the soil buffering index to heavy metals. The data on the reaction of different organization-levelled bioindicators in the system “polluted soil-biota” is given. The materials obtained during assessment of the arable soils contamination in the zone of Pervouralsk-Revda industrial hub showed that the levels of concentration of heavy metals in soils to a large extent correlated with both the composition of industrial emissions and the range of sampling from pollution sources. The maximum level of contamination (Zc index 263-546) was detected in arable soils at a distance of 1.5 km from the SUMZ. The "Crompick" enterprise has a less significant identified impact on the contamination of arable soils. “Extremely dangerous” soil contaminations (index Zc 134) were detected only at a distance of 0.5 km from it. The results of our model experiments allowed us to conclude that the safest level of pollution, when the critical concentration of heavy metals does not accumulate in plants, is the Zc index value below 12. In accordance with the current level of pollution in the survey area, restrictions on the main land use categories were proposed.

MECHANISMS OF CHESTNUT SOIL BUFFERING IN THE ROSTOV REGION

The buffer capacity of chestnut soil in the dry-steppe zone of the Rostov region was studied. Buffer areas were calculated for acidification and alkalinization of chestnut soil. It is shown that chestnut soil is more resistant to acidification than to alkalinization by 1.3 – 3.91 times. The mechanisms of chestnut soil buffering that depend on the amount of carbonates and humus content are revealed

Adsorption and Desorption of Nitrogen, Phosphorus, Potassium, and Soil Buffering Capacity Following Application of Chicken Litter Biochar to an Acid Soil

Adsorption and desorption of nitrogen (N), phosphorus (P), and potassium (K) soils are controlled by pH, pH buffering capacity, organic matter, and cation exchange capacity (CEC). These factors optimized to improve timely availability of N, P, and K crop use using organic amendments such as chicken litter biochar (CLB). The objective of this study was to determine the effects of CLB on N, P, K sorption and pH buffering capacity of an acid soil. Different rates of CLB were mixed with an acid soil for N, P, and K sorption and pH buffering capacity determination. The CLB increased soil pH and pH buffering capacity, but unlike P and K adsorption, the different rates of CLB significantly increased N adsorption, suggesting that this soil amendment has high affinity for N than P and K. Also, because CLB reduced N, P, and K desorption, it suggests that N in particular will be slowly released with time. The reduced N desorption but higher N adsorption further indicates that N can be temporary fixed by CLB. This work has revealed CLB is more effective controlling soil N availability for timely crop use to avoid losses.

ECOLOGICAL MONITORING OF UKRAINIAN AGROLANDSCAPE AS BASIS FOR ITS OPTIMIZATION AND EFFECTIVE USE

The article substantiates the necessity of conducting complex ecological monitoring of agrolandscapes due to the ecologically groundless use of the land, insufficient technical and technological support, implementation of ineffective investment and innovative economic and technological solutions, disturbance of the balance of agrolandscapes through their significant plowing, consolidation of the soil, deterioration of the ratio of arable land and ecology -stabilization lands and nature reserve fund, inefficient implementation of ecological and the Emerald Network, destruction of soil (soil buffering capacity decrease), growing areas of degraded land. A scientifically-based methodology for improving environmental monitoring of agro-landscapes of Ukraine’s territory, their optimization and effective use is proposed. The stages and specifics of carrying out of complex ecological monitoring of various kinds of agro-landscapes, their functional-structural elements, main directions and parameters are presented. The necessity of carrying out of the proposed integrated system of the agro-landscapes ecological monitoring on the territory and creation of regional information and consultation centers on agro-ecological issues has been proved.