Maintenance Of Soil Fertility Research Articles

Shifting focus from external to in situ organic resources – The redesign of four tropical long-term experiments

Long-term experiments (LTEs) are critical for evaluating strategies that can maintain or increase crop yields, soil fertility and soil organic carbon (SOC), and help adapt to climate change. Yet, scientific knowledge is advancing and research questions are evolving. Therefore, it is important to review the objectives of LTEs over time. A change in their design may be necessary to keep the experimental treatments scientifically interesting, innovative, and relevant in the context of evolving agricultural challenges. Here, we describe the process of redesigning four LTEs in Kenya. These LTEs are unique in that they represent four different pedoclimatic conditions but with identical experimental treatments across sites. Initially, they focused on investigating how to maintain or increase SOC and maize yields over time by applying a combination of mineral nitrogen (N) and external organic resources. Specifically, the experimental treatments consisted of maize monoculture with different rates (1.2 and 4 t C ha−1 yr−1) and qualities of organic resources, either with or without mineral N fertilizer input. After about 20 years, it became clear that SOC was lost in most treatments. Therefore, continuing with the current experimental design was not an option. Taking advantage of the fact that the different former treatments led to different levels of soil degradation, we redesigned the LTEs to study the effectiveness of regenerative cropping strategies in rebuilding SOC and increasing crop yields starting from the different levels of soil degradation. The focus shifted from external to in situ organic inputs by increasing the root biomass of the cultivated crops. The newly established cropping system treatments are maize-legume rotation, maize-legume intercropping (double row configuration) and relay intercropping of maize with forage grass. A key finding from the previous phase of the experiments, namely, that external organic inputs with low C:N ratios are most efficient in building SOC, has been incorporated into the redesign. The relative contribution of external versus in situ organic resources is tested by splitting the cropping system treatments into those receiving either farmyard manure or green manure in the form of Tithonia diversifolia prunings and those receiving no external inputs. Split-plot treatments with and without mineral N were retained. The overall objective of studying mechanisms of tropical soil fertility maintenance and, more specifically, SOC formation, remained unchanged. However, the redesign aligned the LTEs with the current state of knowledge and pressing research questions, specifically focusing on the relative effectiveness of in-situ versus external organic inputs in SOC formation.

Polyaspartic Acid Urea Increased Maize Yield by Enhancing Leaf N Turnover Efficiency and Soil Microbial Diversity

The release rates of different nitrogen (N) fertilizers and their matching with plant demand determine crop yields. A field experiment was conducted to investigate the effect of using no fertilizer (N0), regular urea applied at rates of 180 kg ha−1 (N180) and 240 kg ha−1 (N240), controlled-release urea applied at a rate of 180 kg ha−1 (H180), and polyaspartic acid urea (PASP) on maize seed yield, soil microbial community diversity, and leaf N-converting enzymes. XianYu 688 was selected as the test maize variety. All cobs in the sample plots were collected per unit area to estimate maize yield. The enzyme-linked immunosorbent assay (ELISA) was used to determine leaf N-converting enzyme activities. Soil DNA was extracted using the Power Max Soil DNA Isolation Kit and subsequently sequenced using the Illumina HiSeq platform (PE 2500) to determine the microbial diversity and communities. The results showed that the highest seed yields were obtained under N240 and PASP180 treatments. The N-partial factor productivity of the PASP180 fertilizer was significantly higher than that of the other treatments. PASP treatment significantly increased maize seed yield due to the potential of storing more N in the ear leaves. Additionally, partial N productivity showed a significant positive correlation with the soil microbial Shannon, Chao1, and ACE indices, indicating that increased soil microbial diversity promoted N efficiency in maize. Further analysis revealed that PASP treatment increased seed yield by promoting leaf N-converting enzyme activity and soil microbial diversity. The results revealed that nitrate reductase (NR), glutamate synthase (GOGAT), and glutaminase (GLNS) enzyme activities in maize leaves were higher under the PASP treatment than under other fertilizer treatments. The PASP treatment significantly enhanced soil microbial diversity at different maize stages. Our study revealed the effects of using different N fertilizers on seed yield by examining their impact on soil microbial diversity and leaf N-converting enzyme activity. This study provides essential insights into maize production and soil fertility maintenance in the North China Plain.

Effects of organic amendments, biofertilisers and biodynamic preparations on soil properties and leaf nutrient concentrations in grapevine

ABSTRACT Excessive and unbalanced use of chemical fertilisers can lead to depletion of physical and chemical properties of the soil and have negative impacts on the environment. This investigation was conducted at Mizoram University, Aizawl, Mizoram, India and aimed to evaluate effects of organic amendments, biofertilisers and biodynamic preparations on soil properties and leaf nutrient status of grapevine. The experiment was laid out in randomised block design with 14 treatments consisting of different combinations of organic amendments, biofertilisers and biodynamic preparations viz. farmyard manure (FYM), vermicompost (VC), pig manure (PIM), neem cake (NC), Azospirillum, phosphate solubilising bacteria (PSB), potash solubilising bacteria (KSB), Trichoderma harzianum, cow pat pit (CPP) and biodynamic preparations BD500 and BD501. The results demonstrated that the use of organic amendments in combination with biofertilisers and biodynamic preparations enhanced leaf nutrient status as well soil properties in the vineyard. Among all the tested combinations, the highest concentrations of Mn, Zn, chlorophyll a, b and total chlorophyll in the leaves and concentrations of soil organic carbon, inorganic carbon, total carbon, total N, available N, P, K, Mn and Zn, cation exchange capacity (CEC) and abundance of bacteria and Actinomycetes in the soil were recorded with application of PIM + Azospirillum + PSB + KSB + T. harzianum + CPP + BD 500 + BD 501. This treatment was therefore recommended as a suitable option to meet the demand for long-term maintenance of soil fertility as well agroecosystem conservation and sustainability.

A critical review of soil algae as a crucial soil biological component of high ecological and economic significance.

Aero-terrestrial algae are ecologically and economically valuable bioresources contributing to carbon sequestration, sustenance of soil health, and fertility. Compared to aquatic algae, the literature on subaerial algae is minimal, including studies of distinctive habitats such as forest soils, agricultural fields, deserts, polar regions, specific subaerial zones, artificial structures, and tropical soils. The primary goal here was to identify the gaps and scope of research on such algae. Accordingly, the literature was analyzed per sub-themes, such as the "nature of current research data on terrestrial algae," "methodological approaches," "diversity," "environmental relationships," "ecological roles," and "economic significance." The review showed there is a high diversity of algae in soils, especially members belonging to the Cyanophyta (Cyanobacteria) and Chlorophyta. Algal distributions in terrestrial environments depend on the microhabitat conditions, and many species of soil algae are sensitive to specific soil conditions. The ecological significance of soil algae includes primary production, the release of biochemical stimulants and plant growth promoters into soils, nitrogen fixation, solubilization of minerals, and the enhancement and maintenance of soil fertility. Since aero-terrestrial habitats are generally stressed environments, algae of such environments can be rich in rare metabolites and natural products. For example, epilithic soil algae use wet adhesive molecules to fix them firmly on the substratum. Exploring the ecological roles and economic utility of soil and other subaerial algae could be helpful for the development of algae-based industries and for achieving sustainable soil management.

Effect of Mulches on Crop, Soil and Water Productivity: A Review

A mulch is a layer of material applied to the surface of an area of soil. Mulches are used for various reasons in agriculture but water conservation and erosion control are the most important objectives particularly in arid and semi-arid regions. Other reasons for use of mulching include soil temperature modification, weed control, soil conservation and after decomposition of organic mulch add plant nutrients, improvement in soil structure, increase crop quality and yield. Conservation of soil moisture by application of mulches becomes essential for profitable cultivation of the crop under rainfed condition of semi-arid ecosystem. In spite of no assured irrigation in these regions, the moisture conservation technique is not in practice. Mulches not only conserve soil moisture but also impart manifold beneficial effects, like suppression of extreme fluctuation of soil temperature and reduction of water loss through evaporation, resulting in more stored soil moisture, maintenance of soil fertility, suppression of weed growth, improvement in growth and yield. The requirement of water through mulch can further be reduced by using locally available organic materials as mulches which not only save irrigation water but also conserves soil moisture.

Effects of tree species mixing and soil depth on the soil bacterial and fungal communities in Chinese fir (Cunninghamia lanceolata) plantations

Chinese fir [Cunninghamia lanceolata (Lamb.) Hook.] is a critical timber tree species for its fast growth and high yield in southern China and is widely planted in subtropical regions of the country. However, the management of Chinese fir in the form of a monoculture plantation is not conducive to the maintenance of soil fertility and improvements in forest productivity. The establishment of mixed conifer–broad–leaved forests through near-natural transformation is developing into a promising method of forest cultivation for replacing large pure coniferous plantations. Bacteria and fungi are an important part of the soil microbiota and are involved in the soil nutrient cycle. Therefore, this study investigated the response of soil bacterial and fungal communities to the introduction of broad–leaved trees in three types of Chinese fir plantations [Cunninghamia lanceolata monoculture plantation (CMP), C. lanceolata–Castanopsis hystrix Hook. f. & Thomson ex A. DC.–Michelia hedyosperma Law. mixed plantation (CCM), and C. lanceolata–Castanopsis fissa (Champ. ex Benth.) Rehder & E.H.Wilson–Erythrophleum fordii Oliv. mixed plantation (CCE)] located in Guangxi Province, China. And the effect of soil layers (0–20, 20–40, and 40–60 cm soil depths) on the soil microbial communities was further analyzed. The results suggested that tree species mixing significantly affected bacterial and fungal communities, but soil depth only significantly affected bacterial communities (P < 0.01). The relative abundance of Basidiomycetes in CCE (53.91–78.76 %) was significantly higher than that in pure forest (P < 0.05). Bacteria exhibited more complex and multilinked networks in the mixed stands, particularly for the CCE plantation. Mixed planting patterns significantly enhanced bacterial nitrogen fixation and the presence of symbiotic fungi. Redundancy analysis (RDA) and correlation analyses indicated that the microbial community structure was strongly affected by soil environmental factors, with bacteria affected mainly by available phosphorous (AP) and fungi affected mainly by soil enzyme activity and total potassium (TK). In summary, the introduction of broad–leaved species (especially C. fissa and E. fordii) had a significant impact on the soil microbial community, increasing the relative abundance of bacterial nitrogen fixation and symbiotic fungi and generating a complex microbial network. We suggest that changes in AP, TK, and fungal communities should be considered in the near-natural transformation of Chinese fir or soil fertility maintenance and sustainable management to maintain soil fertility.

Role of agroforestry systems in enrichment of soil organic carbon and nutrients: A review

Monocropping systems have intensively exploited natural resources in recent decades, and the indiscriminate use of inorganic fertilizers, combined with agro-chemicals, has resulted in the deterioration of natural resources such as soil and water, resulting in the loss of soil fertility. Agroforestry is an ideal scientific strategy for eco-restoration of degraded areas and sustainable resource management when compared to mono cropping systems. It is a land management and farming strategy that aims to not only produce food from marginal agricultural land, but also to significantly improve the quality of the environment and soil. When compared to regular crop removal in a solo cropping system, leaf litters and their breakdown under tree-based vegetation favour nutrients enrichment. The adoption of an agroforestry system resulted in the accumulation of soil organic carbon, increased the availability of macronutrients and micronutrients, and improved the microenvironment for plant growth. As a result, pairing suitable tree species with agricultural crops can contribute in the maintenance or enhancement of soil fertility. Based on these findings, it is advised that farmers adopt agroforestry systems since they have enormous potential to improve soil fertility, leading to increased crop output and food security.

Long-term maintenance of high yield and soil fertility with integrated soil-crop system management on the Loess Plateau

Ridge–furrow with full film mulching has been widely applied to increase crop yield and water productivity on the Loess Plateau, but it may stimulate carbon (C) mineralization. How to integrate other technological benefits based on this technology for long-term maintenance of high yield and soil fertility is a pressing issue. With the local farmers’ practice (FP) as a control, three integrated soil-crop system management (ISSM) practices integrating fertilizer rates, fertilizer types and planting densities (ISSM-N1, ISSM-N2 and ISSM-MN) were established to improve maize yield and soil quality. Compared with the FP, the maize yield increased by 13.34%, 21.83% and 30.24%, and the soil quality index (SQI) increased by 9.66%, 14.91% and 38.38% for ISSM-N1, ISSM-N2 and ISSM-MN, respectively. However, ISSM-N1 did not significantly increase yield, and ISSM-N2 increased residual soil nitrate and decreased nitrogen (N) partial factor productivity significantly. Compared to the FP, ISSM practices increased soil organic carbon (SOC), labile organic C fractions (LOCFs) and potassium permanganate organic C fractions in the topsoil to varying degrees, but only ISSM-MN reached significant levels for most C fractions. The sensitivity index indicated very easily oxidizable C (24.6%), easily oxidizable C (24.7%), hot-water extractable C (30.8%), labile organic C (24.7%) and particulate organic C (57.3%) were more sensitive than SOC (22.7%). ISSM-MN sequestered significantly higher C than the other treatments. The results of the relative importance analysis and the structural equation model indicated that LOCFs were the direct contributors to yield, while recalcitrant C (CO) was the indirect contributor, revealing the underlying mechanism that CO decomposed to replenish LOCFs and the total N pool with the water soluble C pool as the transit station. Overall, ISSM-MN is the most promising strategy to improve crop yield and soil fertility in the long term on the Loess Plateau.

Impact of soil amendment using indigenous inoculants on tomato growth and yield parameters

Tomato (Lycopersicon esculentum mill) is one of the most important vegetable crops in the world. It is widely acknowledged that using composts and microbial inoculants as soil amendments, rather than industrialized fertilizer and raw manure, could improve soil nutrients, promote soil health and consequently improve crop yields. Global population increase necessitates increasing crop yields. Improvement and maintenance of soil fertility is essential via bio-augmentation in this economic recovery era. In this work, an open field experiment was conducted in other to study the "Yield Effects of Indigenous Microbial Inoculants on Tomato using autochthonous microbial consortia”. The experiment was laid in Randomized complete Block Design (RCBD) with three replicate consisted of six inoculants samples; Indigenous cultures viz; (A) Control, (B)Bacillus mucilaginosus (C) Azospirillum sp., (D) Azotobacter sp. (E) Commercial strains of the inoculants (F) Consortium of B, C and D. The various morphological features/yields parameters measured at intervals includes; no. of leaves, plant height, root length, accumulated dry matter and average fruit weight. The result shows that indigenous inoculants (F) increased tomato overall yield. This research is also of great significance for the development of management strategies for soil maintenance, environmental protection, and resource conservation in Nigeria where soil fertility is on the decrease due to over-use of land in other to achieve food security. From the result of the research, it can be concluded that soil augmentation with indigenous inoculants improves tomato morphological features and yields, hence should be preferred above their exotic commercial strain counterparts because of cost of importation/indigenous product development and GDP growth.

The Toxicity of The Antiparasitic Amitraz in Tropical Soils on The Reproduction of Edaphic Organisms

The objective was to evaluate the effect of environmental toxicity in soils (tropical) with increasing doses of the antiparasitic amitraz on the survival and reproduction of two edaphic organisms, Folsomia candida and Enchytraeus crypticus. Soils contaminated with increasing doses of amitraz caused a significant reduction in the survival and reproduction of the population of adults and juveniles of F. candida, in the natural soil tested, although, for TAS, the reduction was significant only for juvenile individuals. However, the species E. crypticus did not show any sensitivity to exposure to amitraz in all tested soils. We concluded that the addition of increasing doses of this antiparasitic substance can cause imbalance on the terrestrial ecosystem, since it is harmful to at least one member (and perhaps more) of the springtail family, an important edaphic species, whose members play many relevant functions for the maintenance of soil fertility and quality.

Effect of Frequency and Rate of Zinc Application on Nodulation, Chlorophyll Content, Yield, and Quality of Soybean Grown in a Vertisol of Jabalpur, Madhya Pradesh, India

Zinc (Zn) fertilizer is commonly used in nutrient intensively cultivated deficient soils of central, India. Zn is a structural components of plants. However, little is known, on optimum dose of Zn especially in a vertisol of Jabalpur district. This study was required to find out Zn dose for sustainable productivity and maintenance of soil fertility. The study comprised of three frequency levels, Zn application in 1st year only, Zn application in alternate year, and Zn application in every years and five rates of Zn, (0, 2.5, 5.0, 7.5, and 10.0 kg Zn ha-1) was applied in Kharif season. The result of analysis revealed that the highest symbiotic traits viz., nodule number of 36.78, fresh and dry weight (1.09 and 0.31 g plant-1) were found with application of 5 kg Zn ha-1 at 45 DAS at alternate year. The highest SPAD score of 44.98 and relative water content of 62.41 % was recorded with 5 kg Zn ha-1 at 60 DAS and found significant at alternate year. The Zn addition @ 5.0 kg ha⁻¹ through ZnSO4.7H2O to soybean in alternate year which increased by 1.28 to 1.53 (19.53 %) over only single year Zn addition. This was the best practice in a typic haplusterts as it resulted in an average production of 1.54 t ha-1 of seed yield ha⁻¹ over no zinc application (1.24 t ha-1) which increased by 24.19 %. The zinc application improved quality of seed in terms of oil and protein over control. So it was concluded that Zn application at alternate year and 5 kg Zn ha-1 for increasing yield and quality of soybean in a vertisol of Jabalpur district.

Macro Invertebrate Diversity in Different Land Use System and Soil Fertility Status in Relation to Macro Invertebrate Distribution in Shashogo District, Hadiya Zone, Southern Ethiopia

Invertebrate species are predominant in the food webs and among the ecosystem engineers associated with agriculture. They have a major influence on productivity and therefore play a key role in food security. The objective of the present study is to evaluate the ecological role of soil macro invertebrate diversity for maintenance of soil fertility in Shashogo District, Hadiya zone, Southern Ethiopia. Both field and laboratory work were applied during investigation of the study. Invertebrate’s diversity was identified and Soil samples were collected from different sites and evaluated for soil fertility status. The physico-chemical analysis; organic carbon content, total nitrogen, available phosphorous, available K, soil pH, soil texture, sodium etc… was analyzed. The main soil macro invertebrates identified were Termites ( order Isoptera), Beetles (order Coleoptera), Wasps (Hymenoptera), Millipedes (order diplopoid), Centipedes (chilopoda), Ants (Hymenoptera) and Earthworm (order Opisthopora). The average selected chemical properties of the soil were Soil PH (5.60), Total Nitrogen (0.23), and Organic carbon (2.44), Phosphorus (2.63), Calcium (22.73), Potassium (0.376) and Sodium (0.096). There is significant association between soil macro invertebrate groups and selected soil physical and chemical properties. To conserve soil resources, it needs highest attention of policy makers as well as land use planners to concentrate their efforts on land management strategies based on land use system.

Land cover change assessment using random forest and CA markov from remote sensing images in the protected forest of South Malang, Indonesia

Protected forest has important roles in protecting life support systems through water management, maintain micro climate stability, flood prevention, erosion control, prevention of seawater intrusion and maintenance of soil fertility. Deforestation in protected forest areas will reduce the roles, however, deforestation appeared to occur in forested areas of Bantur Regency. Infrastructure development which is growing rapidly and the compleexity of economic activities is driving deforestation in this region. The deforestation caused water supply problems, landslide and decreased endemic bird population (“rangkong”) in study areas. Therefore it is necessary to identify deforestation through land cover change assessment. This study aims at (1) quantifying the forest land cover changes in protected forest areas of Bantur and Donomulyo Regency, (2) identifying environmental condition in protected forest areas of Bantur and Donomulyo Regency. Landsat TM, ETM+ and 8 were used together with Random Forest classification for mapping the forest areas. Carbon Monoxide (CO) and temperature were used as biophysical factors in the model. The results of this study suggested the continuing deforestation with the existence of roads, economic activity, and tourism development triggered the deforestation pattern. Role of community was also found to affect the nature of deforestation.

Understanding the intricate tradeoffs among ecosystem services in the Beijing-Tianjin-Hebei urban agglomeration across spatiotemporal features

Revealing the intricate interactions between ecosystem services and their values is essential for the comprehensive management of diverse ecosystems. However, understanding tradeoffs among various ecosystem services and their influencing factors, especially at different spatial scales, remains challenging, primarily due to the difficulty in quantifying cultural services. In this study, we conducted a comprehensive analysis of the ecosystem service value (ESV) at both grid and county scales in the Beijing-Tianjin-Hebei urban agglomeration from 2000 to 2020, considering the representation of different ecosystem services. Our investigation aimed to elucidate tradeoffs among ecosystem services and identify key natural-social-economic-climate drivers. The key findings are as follows: (1) Over the study period, the overall ESV in the Beijing-Tianjin-Hebei urban agglomeration exhibited an upward trend, with regulation of waterflows, water body, and forest land making the largest contributions. (2) At the grid scale, there were 3 tradeoffs and 52 synergies among multiple ecosystem services in 2000, which increased to 18 tradeoffs in 2020, indicating a considerable degradation of numerous ecosystem services. Conversely, at the county scale, all ecosystem services exhibited a synergistic relationship. (3) The most significant synergistic effect was observed between regulation of waterflows and maintenance of soil fertility, while the most prominent tradeoff effect was identified between food production and waste treatment. (4) Social-economic factors exerted a more substantial influence on ESV, followed by climate factors, whereas the impact of natural factors was limited. GDP emerged as the primary single driver of total ESV, while farmland production potential played a crucial role in shaping the 11 ecosystem services. Notably, GDP-temperature and GDP-farmland production potential output were identified as the most influential dual factors. These findings underscore the importance of simultaneously enhancing economic development, controlling temperature rise, and improving food production as essential measures to enhance ESV.

Crop diversification effects on soil organic carbon and nitrogen storage and stabilization is mediated by soil management practices in semiarid woody crops

Crop diversification is a promising strategy to mitigate climate change through soil carbon sequestration while ensuring soil fertility maintenance and food security. Here, we assess the impact of different inter-cropping practices on soil organic carbon (SOC) and nitrogen (N) storage and stabilization under rainfed and irrigated semiarid conditions. Under rainfed conditions, an almond (Prunus dulcis Mill.) monocrop was compared with an almond inter-cropped with caper (Capparis spinosa) or with winter thyme (Thymus hyemalis). Under irrigated conditions, a mandarin (Citrus reticulata Blanco) monocrop was compared with a mandarin inter-cropped with an annual crop rotation (including Hordeum vulgare, Vicia sativa and Vicia faba) or with a triennial crop rotation (including Vicia faba, Portulaca oleracea and Vigna unguiculata L.). The SOC and N stocks, SOC mineralization rates, water-stable aggregates and associated OC and N contents were estimated at 0–10 and 10–30 cm depth in each monocrop and inter-cropping system after three years. Contrasting effects of inter-cropping on SOC and N stabilization were found in the rainfed and irrigated systems. The combination of inter-cropping and no tillage did not affect the SOC stocks or mineralization rates at any soil depth in the rainfed system, while it significantly increased the OC and N contents within the large macro-aggregates in the subsoil. Compared to the irrigated mandarin monocrop, the mandarins inter-cropped with the annual crop rotation showed a significant increase of 10% and 18% in the topsoil and subsoil N stocks, respectively, while the SOC mineralization rates were reduced by 30% at both soil depths. On the contrary, the topsoil SOC stock in the mandarins inter-cropped with the triennial crop rotation were reduced by 38% compared to the monocrop. Significant reductions ranging between 24% and 66% were also observed in the OC and N contents associated to the macro- and micro-aggregates in the topsoil and subsoil of both crop diversifications compared to the monocrop system. Our results highlight the potential of inter-cropping rainfed woody crops with perennials for boosting SOC and N storage and stabilization. In irrigated woody monocrops, inter-cropping with annual crop rotation schemes that include two or more leguminous and reducing tillage frequency operations seems to be more appropriate in terms of SOC and N stabilization.

Natural fertility and intrinsic fragility of soils in the Brazilian Cerrado

This study aimed to evaluate the attributes of natural fertility and intrinsic fragility of the soils of Ivinhema River Basin (BHI), to subsidize agricultural development projects and environmental control and monitoring bodies. For this purpose, 62 soil samples were collected, at a depth of 0 to 20 cm, in areas of native vegetation belonging to the state of Mato Grosso do Sul – Brazil. The characteristic climate of the study area is of the humid mesothermal subtype (Cfa) without drought. The predominant vegetation is of the Cerrado type and the geological substrate is predominantly composed of the Serra Geral and Caiuá Formation. The samples were air-dried and the physical attributes (sand, silt, and clay) and chemical variables (pH H2O, CaCl2, KCl, ∆pH, Al3+, m%, H + Al, Ca2+, Mg2+, K+, CEC, SB, V%, OC, P, Cu, Fe, Mn, and Zn) were determined according to methodologies in Embrapa's soil analysis methods manual. The data obtained were evaluated by descriptive statistics and principal component analysis. The results showed a great variety of soils inside the basin, whose natural fertility was high for the Leptsol, Regosol, and Nitisol soils, and low for the Argiluvic Plinthosol, Petroplinthic Plinthosol, and Planosol soils. The sandy soils showed lower levels of organic carbon and negative surface loads, which shows less capacity to retain cations essential to plant nutrition and less retention of environmental contaminants if any. Regarding the textural fragility of the soils of BHI, it was possible to verify the high sensitivity of the soil to erosion and susceptibility to the contamination of groundwater or infiltrated water. The data shown in research can fill the gaps of knowledge and/or for adapting conservation practices of agricultural soils that are more susceptible to erosive processes, as well as for environmental control and monitoring bodies and/or studies of area recovery and maintenance of soil fertility.

Best Management Practices for Sustainable Agriculture

The present estimate of the number of people on Earth is 8 billion, but by the middle of the century, it is predicted to reach 9 billion. Simultaneously, the cultivable farm land is being lost to expanding urban areas, industrialization and climate change. The recent World Bank Report estimated that to feed 9 billion people, food production needs to scale up by 70% by 2050. In the present context, the significance of sustainable agriculture is crucial in ensuring the sustenance of the population and mitigating the adverse effects of climate change. Environmental protection, resource conservation, soil fertility maintenance and improvement are the key goals of sustainable agricultural practises. Sincere efforts have been taken to discuss the various sustainable agriculture methods and practices in this assessment.

FORMATION DIRECTIONS OF PUBLIC ADMINISTRATION OF STRATEGIC DEVELOPMENT OF UKRAINIAN AGRICULTURAL COMPLEX

The article mentions the importance and urgency of considering the issues of the state policy of the agro-industrial complex of Ukraine, which acquires a new meaning for the military economy in the context of the rapid growth of production and export volumes during the last decade. In the conditions of a full-scale invasion of the Russian Federation, the sharp decline and destruction of industrial production and the curtailment of metallurgical exports led to the accelerated restructuring of Ukraine's economy, significantly increasing the importance of the agricultural sector in its structure and exports. It was determined that the priority of the development of the agricultural sector and rural areas is determined by the exceptional importance of the production of agricultural products and food in human life. It has been proven that the development of the policy for the development of the food industry, the implementation of target programs for the development of agriculture in order to ensure the satisfaction of the population's needs in food products are the vectors of the development of the domestic agro-industrial complex. Among the important and significant directions of the development of innovative processes, the following vectors are highlighted: technological modernization and re-equipment of the infrastructure of the agro-industrial complex; implementation of energy- and resource-saving technologies for obtaining and storing agricultural products, including; maintenance of soil fertility, development of adaptive technologies - agro-ecosystems and agro-landscapes; development of production of organic agricultural products; creation of a modern system of information and infrastructural support for innovative activities in the agricultural sector; strengthening the role of state organizations in the activation of innovative activities.

Multiple mechanisms drive biodiversity-ecosystem service multifunctionality but the dominant one depends on the level of multifunctionality for natural forests in northeast China

Biodiversity plays a key role in maintaining and regulating ecosystem multifunctionality (EMF). However, there remains a knowledge gap on the ecological mechanisms behind the relationship between biodiversity and EMF (BEMF), and how these mechanisms vary with EMF gradients, especially at large scale. We used the dataset of 2224 permanent sample plots in Jilin Province, northeast China to test three BEMF mechanisms and their variations with EMF, including mass ratio, ecological niche complementarity and the green soup hypotheses. Biodiversity metrics were taxonomic, structural, phylogenetic, functional diversity and functional identity. EMF was composed of five services: water retention, soil conservation, carbon storage, stand productivity and soil fertility maintenance. EMF was measured using both the averaging (as the average of the standardized values of all services) and threshold (as the number of services passed a threshold) approach. Totally 23 piecewise structural equation models (pSEMs) were developed for EMF with the threshold level ranging from 5% to 95% by an interval of 5%. Results showed that stand biomass had strong positive effect on EMF. Stand structural diversity had significant direct and indirect effects on EMF, but taxonomic, functional diversity and functional identity only had significant direct and indirect effects on EMF at low thresholds. Stand age had significant direct effects on EMF and indirectly enhanced EMF through stand structural diversity and biomass. Our results provided strong evidence that EMF was driven simultaneously by mass ratio, niche complementarity and green soup hypotheses, but the dominant mechanism was dependent on EMF level. Generally, the green soup hypothesis played more important role in explaining EMF. Recommendations for maintaining high functional and structural diversity and large biomass for maximizing EMF were discussed for forest management.

Spatial variation of soil characteristics affected by biochar materials from traditional slash and burn agriculture in Sabah, Malaysia

ABSTRACT Traditional slash-and-burn agriculture has been practiced for centuries in Southeast Asia. Our past study has identified distinctly different soil profile characteristics over a very short distance within a sloping field. In order to accurately estimate the potential of the traditional slash and burn cropping system for soil C sequestration as well as the maintenance of soil fertility, the spatial variation of soil C stock, soil nutrient status, and soil reactions were studied in Sabah, Malaysia. A triangular grid was used to conduct intensive soil sampling with an interval of about 5.8 m and a total of 71 locations. Total C (TC) stock was high with a mean of 34.9 Mg ha−1 and the spatial variation was extreme with a CV of 57.3% within a field. The spatial range was also short at 14.3 m. All soil nutrients had high CVs especially for available phosphate at 90.2% and the lowest for exchangeable potassium at 44.0%. Available phosphate was the most limited major nutrient when referencing the Japanese fertilizer guidelines, and its spatial distribution was affected by soil acidity status, especially exchangeable Al. Potential improvements of the production systems can be made by the application of lime materials in locations where TC content was low. However, the introduction of any external inputs requires careful assessment of not just crop productivity but also its consequences for long-term sustainability of the system. Future studies are anticipated in order to understand the response of crop productivity by pH improvement as well as the use of fertilizers.