Soil nematode abundance and functional group composition at a global scale.

Soil organisms are a crucial part of the terrestrial biosphere. Despite their importance for ecosystem functioning, few quantitative, spatially explicit models of the active belowground community currently exist. In particular, nematodes are the most abundant animals on Earth, filling all trophic levels in the soil food web. Here we use 6,759 georeferenced samples to generate a mechanistic understanding of the patterns of the global abundance of nematodes in the soil and the composition of their functional groups. The resulting maps show that 4.4 ± 0.64 × 1020 nematodes (with a total biomass of approximately 0.3 gigatonnes) inhabit surface soils across the world, with higher abundances in sub-Arctic regions (38% of total) than in temperate (24%) or tropical (21%) regions. Regional variations in these global trends also provide insights into local patterns of soil fertility and functioning. These high-resolution models provide the first steps towards representing soil ecological processes in global biogeochemical models and will enable the prediction of elemental cycling under current and future climate scenarios.

Harmonics, evolutionary generators, DANCE, and HEAR-functional dimensions.

Evolution of the major kingdoms of life has spanned over the last 4 billion years on Earth. Studies of the process comprise different fields of study with alternative perspectives. This paper focuses on mathematic unification of the subject area; enriching an engineering based structure to advance our understanding of pathways which lead to distinct constructs in life, furthering geographic bordering processes with biological context. Application of logistic regression requires partitioning of variance within cellular and molecular systems; use of higher mathematic technique (multi-objective genetic algorithm) generates variance within the different scales of evolution, the result of which is analogous with the Fisher equation model of gene distribution within populations. Laboratory and field studies were integrated to illustrate emergence in evolutionary processes in the terrestrial/soil environment. Nematological field and laboratory trials validate the existence of triangular relationships within biological communities; further harmonic constants between interacting species may be found with emergent consequence. We distinguish different strategical groupings in the soil community, with the core groupings recognized with Meloidogyne spp. illustrating positive (emergent) growth; Radopholus similis (neutral growth), and Helicotylenchus pseudorobustus (negative growth). The patterns of emergent systems are shown in the extremes of Morocco's dynamic soil environment. Fuzzy classification methods: Mamdani, Takugi-Sugeno-Kang; additional novel DANCE (Differential Algorithmic Network Centered Emergence) and functional expressions HEAR (Harmonic Evolutionary Algorithmic Resilience), are recommended to give a basis for development of constructs covering different categories of life.

Floristic biodiversity, biogeographical significance, and importance of Morocco's Arganeraie Biosphere Reserve.

The coastal and subcoastal areas of west-central Morocco (Safi to Draa River, the Souss Valley, and the southern part of the western High Atlas and northern and southern slopes of the western Anti-Atlas) are characterized by typical Infra-Mediterranean vegetation ranking them amongst the important of the remarkable borderlands of North Africa. The flora is determined by complex historical and environmental factors occurring since the Tertiary period. The originality of this sector is due to the presence of the argan tree (Argania spinosa (L.) Skeels), Moroccan gum (Acacia gummifera Willd), olive trees (Olea europaea L. subsp. maroccana (Greuter & Burdet) P. Vargas & al.), a thermophilic flora adapted to an arid climate with several endemic species. This flora constitutes the final barrier against the desert and is of environmental and socioeconomical interest. Leaves and fruits provide forage material, while wood is used for fuel. Argan fruits are collected for their oily constitutes and for nutritional, cosmetic, and medicinal properties. Additionally, many species of Argan ecosystems are used in medicine and cosmetics. Recognizing its ecological value and local economic importance, the Argan region was declared a UNESCO Biosphere Reserve in 1998. Despite their biogeographical, historical, and socioeconomic value, vegetation structures in west-central Morocco are vulnerable and threatened by human activities. They exhibit high levels of degradation due to increasing clearance, overgrazing, and overexploitation. The area requires high conservation priority and sustainable management strategies for key species and genetic diversity.

Water purification plantations for oil and gas industries in Iran.

Water treatment for human uses is a vital asset to economic development. This article focuses on a combination of physical, biological, and chemical processes. Methods of water treatment require concrete or steel base structures, rendering them heavy, costly, and time-consuming to establish. Water treatment systems should be economically viable and practicable in design for developing societies; hence, structural builds should be simplified. Novel structures, a series of polyethylene cyclonic ponds for water treatment, were built and tested. Tanks were equipped with a settled material central outlet, water side outlet, and a pump shower system that enabled sludge removal without mechanical intervention. A freely flowing vortex was produced, aerated, given a biological treatment, and finally mixed with a chemical treatment step. Test establishment of the batch system enabled improvement in water quality, with removal performance as follows: TSS (total suspended solids) = 98%, UV254 absorbance = 50%, DOC (dissolved organic carbon) = 56%, and turbidity=95%. The batch system builds of the current study required short construction time and were economically priced. Cyclonic ponds are suited to diverse usage. The value may be felt in the improvement of water quality for human consumption, utility, and ecosystem services to counter the extensive pollution caused by oil and gas extraction and other industries.

Optimization of tomato waste composting with integration of organic feedstock.

Valorization of waste by composting converts organic waste into valuable organic supplements. Physicochemical characteristics of tomato waste (TW) limit the efficiency of the composting process. To overcome these challenges, different mixtures were investigated by integration of olive pumice (OP), sheep manure (SM), chicken manure (CM), and sawdust as bulking agents for the optimization of the composting process. Evaluations of the composting process and compost quality were carried out to measure the temperature profile, organic matter (OM) losses, concentrations of humic substances, and macro-nutriments. The results showed that the type and ratio of feedstock in the mixture influenced the temperature of the composting process. In mixtures with SM and OP, the temperature exceeded 55 °C for more than 2 weeks, ensuring hygienization. Additionally, phosphorus and potassium significantly increased when SM and CM were added to the composting mixture. The addition of OP increased the concentrations of humic acid-like carbon (CHA) and fulvic acid-like carbon (CFA). Higher content of humic substances was recorded when SM and OP were used as composting feedstock. Using SM in the mixture was found to be more efficient than CM and constitutes a suitable feedstock for composting of tomato waste, achieving successful co-operation of agronomic and animal farm sectors.

Phytoparasitic nematodes of organic vegetables in the Argan Biosphere of Souss-Massa (Southern Morocco).

Agroecological productivity of the Arganeraie Biosphere Reserve of Morocco is limited by the wide spread and dynamics of plant parasitic nematodes (PPN). Ecological studies of nematode communities are required to develop effective biological management of these bioagressors as conventional control methods of PPN are inadequate and have persistent harmful effects. Fifty-nine organic vegetable soils in Souss-Massa were nematologically sampled, and assessment of taxonomic proliferation was made in relation to host species, geographical origin, and climatic and microclimatic factors. Twenty-four nematode genera were identified as obligate and facultative plant feeders. Taxonomic diversity increased from Chtouka to Taroudant and Tiznit provinces. Soil texture, organic matter, pH, nitrogen, zinc, magnesium, copper, altitude, and humidity and temperature were seen to effect driving roles in the abundance, distribution, and community structures of nematodes. The most prevalent taxa posing a high risk to organic agriculture of Souss Massa were needle nematodes (Longidorus spp.) and root-knot nematodes (Meloidogyne spp.). Edaphic and climatic variables effected nematode populations greatly. A combination of biological treatments and appropriate agroecological practices restricting important economic PPN growth and enhancing soil quality are required to achieve sustainable management in the area.

Inoculation of tomato plants with rhizobacteria suppresses development of whitefly Bemisia tabaci (GENNADIUS) (HEMIPTERA: ALEYRODIDAE): Agro-ecological application.

In agroecosystems, soil biodiversity is increasingly becoming more recognized as providing benefits to both plants and human health. It performs a wide variety of ecological services beyond the recycling of nutrients to plant growth and manage pests and diseases below the economic injury level. This study investigated the effects of three Pseudomonas isolates (Q172B, Q110B and Q036B), isolated from untreated tomato rhizospheric soil, as a biological control agent of Bemisia tabaci which is a key pest of tomato crops. The study was conducted under laboratory and glasshouse conditions and the water treatment was used as a control. Adult mortality rates were assessed during three days at 24h interval and larva mortality rates were evaluated during six days after treatment at 48h interval. Results indicate that Q036B isolate has a faster effect on B. tabaci adult and larvae. Under laboratory conditions, all three Pseudomonas isolates (Q110B, Q036B and Q172B) have a significant effect on B. tabaci adult mortality compared to control. The earliest and the most important mortality rate of 76% was recorded by Q036B. Two isolates Q036B and Q110B caused a significant mortality on B. tabaci larvae; with highest mortality effect (79%) was observed for Q036B compared to control. However, Q172B has no mortality effects on B. tabaci larvae under laboratory conditions. In glasshouse conditions, only Q036B provided high mortality rates of 91% at 168h after treatment. The results of this study indicate that the Pseudomonas isolate Q036B significantly suppresses B. tabaci in tomato plant and could substitute the excessive use of chemicals. Current research indicates that soil biodiversity could be promising to preserve agro-ecological sustainability.

A global database of soil nematode abundance and functional group composition.

As the most abundant animals on earth, nematodes are a dominant component of the soil community. They play critical roles in regulating biogeochemical cycles and vegetation dynamics within and across landscapes and are an indicator of soil biological activity. Here, we present a comprehensive global dataset of soil nematode abundance and functional group composition. This dataset includes 6,825 georeferenced soil samples from all continents and biomes. For geospatial mapping purposes these samples are aggregated into 1,933 unique 1-km pixels, each of which is linked to 73 global environmental covariate data layers. Altogether, this dataset can help to gain insight into the spatial distribution patterns of soil nematode abundance and community composition, and the environmental drivers shaping these patterns.