Fungal Perspective of Pine and Oak Colonization in Mediterranean Degraded Ecosystems

Forest restoration has become one of the most important challenges for restoration ecology in the recent years. In this regard, soil fungi are fundamental drivers of forest ecosystem processes, with significant implications for plant growth and survival. However, the post-disturbance recovery of belowground communities has been rarely assessed, especially in highly degraded systems such as mines. Our aim was to compare forests and mined systems for biomass and structure of fungal communities in soil during early stages of tree establishment after disturbance. We performed ergosterol analysis and PacBio and Illumina sequencing of internal transcribed spacer 2 amplicons across soil layers in P. sylvestris, Q. robur and Q. ilex (holm oak) forests and naturally revegetated mined sites. In pine forests, total fungal biomass was significantly higher in litter and humus compared to mineral layers, with dominance of the mycorrhizal genera Tomentella, Inocybe and Tricholoma. Conversely, in oak forests the most abundant mycorrhizal genera were Tomentella, Cortinarius and Sebacina, but the biomass of saprotrophic fungi was greater in the litter layer compared to mycorrhizal fungi, with the genus Preussia being the most abundant. In the revegetated mined sites, ectomycorrhizal fungi dominated in the humus and mineral layers, with the mycorrhizal genus Oidiodendron being dominant. In contrast, in holm oak forests saprotrophic fungi dominated both soil humus and mineral layers, with the genera of Alternaria, Bovista and Mycena dominating the soil humus forest layer, while the genus Cadophora dominated the mineral layer. The habitat-specific differences in soil fungal community composition and putative functions suggest that an understanding of soil–plant–microbial interactions for different tree species and use of specific soil/litter inoculum upon planting/seeding might help to increase the effectiveness of tree restoration strategies in Mediterranean degraded sites.

Mineral-associated soil organic matter: characteristics and behavior under diagenesis

The main part of soil organic matter (OM) is mineral-associated: 88 ± 11% of С and even more – 93 ± 9% of N. The aims of the given study were: 1 – to demonstrate experimentally the adsorption selectivity of organic compounds towards minerals with different physico-chemical properties (palygorskite vs montmorillonite); 2 – to characterize mineral-associated OM of buried Late Holocene palaeosols and estimate its diagenetic transformations; 3 – to investigate the OM of humin from modern soils of different genesis and Pleistocene and Holocene palaeosols and estimate its diagenetic transformations. The basic soil properties were determined using standard methods. Clay fractions (<2 um) – natural organo-mineral complexes (OMC) were obtained by sedimentation, their mineralogy was studied by XRD. The elemental composition of OM was studied with CNS-analyzer. The structural characteristics of organic matter were determined with the solid-state 13C-NMR-spectroscopy and FTIR-spectroscopy, isotopic composition of C and N – by mass-spectrometry. The obtained results show that the characteristics of mineral-associated OM depends on the properties of mineral “filter” as well as the fate of OM under diagenesis: how long, in what quantity and quality it will persist. It was shown that palygorskite adsorbed predominantly O-alkyls, which are chemically strongly bound. As a result, the age of fulvic type humus in palygoskite palaeosols can reach 300 My. From other side humus of smectitic paleosols of the same age is present by deeply transformed aromatic structures (“coal”). Mineral-associated OM of buried under kurgans Holocene palaeosols contains more alkyls and carboxylic groups, is less aromatic in a comparison with OM of the respective soils. The specific feature of mineral-associated OM is its enrichment in N-compounds. The later are present by both vegetal and microbial compounds, and demonstrate the large affinity towards the mineral surfaces. The formation of chemical bounds between them provides the persistence of OM in OMC. E.g. H2O2 treatment results in preferential destruction of C-rich compounds and oxidized OM demonstrates larger C/N values. Mineral-associated OM of buried Holocene soils keeps the decreased values of C/N (7–14 vs 14–21 for OM of whole soils). Additionally they are characterized by heavier isotopic composition of δ15N in a comparison with the respective soils (5–11‰ vs 6–9‰). It could be explained either by the accumulation of microbial N, or increasing of the humification degree – the loss of aliphatic C and increasing of aromaticity. Humin is the considerable part of soil humus. Experimentally shown that OM of humins both of soils and OMC is enriched in O-alkyls and C of acetal groups. OM of humins are not homogeneous, and consists from at least two groups: mineral-associated OM and partly mineralized plant fragments. As a consequence, the content of humin in OMC is smaller in a comparison with respective soils. It is concluded that mineral-associated OM and humin as well as soil humus represent dynamic soil systems.

Influence of Method, Duration and Norms of Application of Logon Minefield Bentonite Mud on the Amount of Nutrients in the Soil

The article discusses the impact of the application of bentonite sludge from the Logan deposit in different methods, terms and standards on the nutrients in the soil in the conditions of meadow saline, moderately saline soils of Central Fergana.As a result of application of Logan bentonite mud under autumn plowing at the rate of 1.5-3.0 t / ha per year, in three years in the driving layer of the soil humus 0.003-0.007%, total nitrogen 0.002-0.006%, phosphorus 0.005-0.015%, potassium 0.012-0.030 % increase and reports of improved agrochemical properties

Respon Tanaman Pakcoy (Brassica rapa L.) Pada Beberapa Media Tumbuh Organik

AbstrakMedia tanam adalah bagian dari faktor penting untuk menentukan perkembangan dan pertumbuhan tanaman. Kualitasnya sangat menentukan produktivitas tanaman. Penelitian ini bertujuan mengkaji pengaruh kombinasi beberapa material organik, yaitu arang sekam, kompos, dan rabuk kandang buangan kambing sebagai media tanam terhadap pertumbuhan dan hasil tanaman pakcoy dan menentukan kombinasi material organik terbaik. Pelaksanaan penelitian berada di Green House Universitas Nusa Bangsa, Bogor. Waktu penelitian di bulan April sampai dengan Juni 2020. Metode pada kajian menggunakan metode penelitian eksperimental, dengan tujuh perlakuan yang dirancang secara acak lengkap (RAL). Perlakuan yang dicobakan adalah: 1) P0: tanah (kontrol), 2) P1: tanah dan kompos perbandingan volume 1:1, 3) P2: tanah dan arang kulit padi perbandingan volume 1:1, 4) P3: tanah dan rabuk kandang kotoran kambing perpaduan isi 1:1, 5) P4: tanah, kompos dan arang kulit padi dengan perpaduan volume 1:1:1, 6) P5: tanah, humus, dan rabuk kandang kotoran kambing perbandingan volume 1:1:1, dan 7) P6: tanah, kompos, arang kulit padi dan rabuk kandang kotoran kambing volume perpaduan 1:1:1:1. Percobaan diulang 3 kali untuk setiap unit. Hasil kajian menunjukkan bahwa kombinasi material organik memberikan respon berbeda terhadap kemajuan dan hasil tanaman pakcoy (Brassica rapa L.). Pola pertumbuhan (tinggi tanaman dan kuantitas daun) pada P3, P5 dan P6 sama. Perlakuan terbaik adalah P5 (kombinasi tanah, humus, rabuk kandang kotoran kambing dengan pepaduan volume media 1 : 1 : 1 (P5) yang sama nyata dengan perlakuan P3 dan P6. AbstractPlanting media is part of the important factors to determine the development and growth of plants. The quality will determine the productivity of the plant. This study aims to examine the effect of a combination of several organic materials, namely husk charcoal, compost, and goat manure as a planting medium on the growth and yield of pakcoy plants and determine the best combination of organic materials. The research was conducted at the Green House of Nusa Bangsa University, Bogor. The time of the study was from April to June 2020. The method in this study used an experimental research method, with seven treatments designed at completely randomized (CRD). The treatments were: 1) P0: soil (control), 2) P1: soil and compost volume ratio 1:1, 3) P2: soil and rice husk charcoal volume ratio 1:1, 4) P3: soil and manure goat manure a mixture of 1:1 content, 5) P4: soil, compost and rice bran charcoal with a volume combination of 1:1:1, 6) P5: soil, humus, and goat manure ratio 1:1:1, 7) P6: soil, compost, rice husk charcoal and goat manure manure mixed volume 1:1:1:1. The experiment was repeated 3 times for each unit. The results of the study showed that the combination of organic materials gave different responses to the progress and yield of pakcoy (Brassica rapa L.). The growth pattern (plant height and leaf quantity) at P3, P5 and P6 were the same. The best treatment was P5 (a combination of soil, humus, goat manure manure with a mix of 1:1:1 (P5) media volume which was as significant as P3 and P6 treatments.

Effects of fertilizer practice on fungal and actinobacterial cellulolytic community with different humified particle-size fractions in double-cropping field

Cellulose plays an important role in maintaining or improving soil carbon (C) cycling and soil fertility of paddy field. There had close relationship between functional cellulose genes (cbhI and GH48) with characterize of soil organic matter chemical components (fulvic acid and humic acid) and soil physical fractions. However, there is still limited information about how functional cellulose degradation response to long-term fertilizer management and their relative importance for C sequestration under the double-cropping rice paddy field in southern of China. Therefore, the objective of this study were investigated the effects of 34-years long-term fertilizer regime on community abundance of cbhI and GH48 genes in five soil particle-size fractions (> 2000 μm, 2000–200 μm, 200–50 μm, 50–2 μm and 2–0.1 μm) by using polarization magic angle spinning 13C nuclear magnetic resonance spectroscopy. The field experiment was included four different fertilizer treatments: chemical fertilizer alone (MF), rice straw and chemical fertilizer (RF), 30% organic manure and 70% chemical fertilizer (OM), and without fertilizer input as a control (CK). The results showed that distribution of soil humus and cellulolytic microbial community abundance was significant increased under long-term application of crop residue and organic manure condition. And the FA, HA and HM C contents in > 2000 μm and 2000–50 μm fractions with MF, RF and OM treatments were significant higher than that of CK treatment. Meanwhile, the alkyl C and Oalkyl C groups of FA and HA in > 2000 μm fraction with MF, RF, OM and CK treatments were higher than that of the other fractions. There had higher AL% and lower ARO% of FA and HA in different particle-size fractions with MF, RF, OM and CK treatments. The results indicated that abundance of cbhI and GH48 genes in different particle-size fractions with RF and OM treatments were significant increased, compared with CK treatment. There had significant positive correlation between soil humus C components (FA and HA) with abundance of cbhI and GH48 genes, and the o-alkyl C and AL% of FA were positively correlated with abundance of cbhI and GH48 genes. As a result, the community abundance of cbhI and GH48 genes were significant increased under combined application of crop residue and organic manure with chemical fertilizer condition.

Production of barueiro seedlings in different substrates

Barueiro (Dipteryx alata Vog.) is one of the species native to the Brazilian cerrado that has economic potential. Thus, for the implantation of commercial orchards of this fruit tree, it is important to produce quality seedlings. This study aimed to evaluate the growth of barueiro seedlings under different substrates containing organic residues in the municipality of Nova Xavantina-MT. The experimental design used was randomized blocks (RBD), with 7 treatments (soil (control); soil + bovine manure (2: 1); soil + coffee husk (3: 1); soil + humus (2: 1); soil + coffee husk + humus (3: 1: 1); soil + coffee husk + bovine manure (3: 1: 1); and soil + humus + bovine manure (3: 1: 1)) and 4 replicates, with ten plants per plot, totaling 280 seedlings. Treatments consisted of substrates formulated with different proportions of soil, bovine manure, coffee husk and earthworm humus. Substrate containing only soil (control) provided greater plant height, stem diameter, number of leaves, number of leaflets, shoot and root fresh and dry mass and Dickson Quality Index. In general, residues tested did not favor the growth parameters evaluated, possibly because barueiro is a species native to the Cerrado, not very demanding in soil fertility. Under the conditions of this work, it is recommended the use of soil in the formulation of substrates to produce barueiro seedlings. The addition of organic matter to the soil had negative effect on seedling development.

Distribution and ecology of dictyostelids in Madagascar

Samples for isolation of dictyostelid cellular slime molds were obtained from 20 collecting sites at 18 localities in south central and southeastern Madagascar during May 2009. At least thirty species of dictyostelids representing seven genera were recovered from 52 samples of soil/humus. This total included 17 species described as new to science, 13 species already known from various localities throughout the world, and four isolates that remain unidentified. Fourteen of the new species isolated from these samples are members of the whorl-branched, light-spored genus Heterostelium (formerly Polysphondylium). The overall level of species richness of dictyostelids in Madagascar is greater than what is known for all of mainland Africa sampled to date. Levels of biodiversity in Madagascar were higher for mesic than for xeric vegetation types, and each of the newly described species of Heterostelium appeared to have a limited distribution among the localities sampled.