Effect of Soil Treatments and Amendments on the Nematode Community under Miscanthus Growing in a Lead Contaminated Military Site

Abstract

Applying phytotechnologies with energy crops on lands contaminated with trace elements provides cellulosic biomass and improves soil health. The process can be reflected in changes in the soil nematode community structure. This study assessed the nematode community composition of soil with Miscanthus grown with different agronomic practices. The research was conducted at Fort Riley, Kansas, USA, in soil with aged contamination by Pb at 1000 to 1500 mg/kg. The experimental design was a randomized complete block composed of four replications of five treatments: Control-undisturbed mixed plant cover and four conditions of Miscanthus growth, which consisted of No-till, Till (immediately before planting), Till + P, and Till + biosolids. Analysis of abundance, diversity, and community functional status indicators showed differential sensitivity of nematode taxa to agronomic treatments. Significant transformations in the nematode trophic group structure occurred under Miscanthus cultivation compared with the undisturbed mixed plant cover. Shannon and Pielou index response to agronomic treatments illustrated decreasing nematode community diversity with all Miscanthus agronomic conditions. However, agronomic practices led to increasing nematode community maturity, but those effects varied between spring and fall seasons. Increasing herbivores and omnivore-predators were the primary drivers of the observed changes in the nematode community due to planting Miscanthus. The nematode ecological structure indicators suggested that growth in Pb-contaminated land using different agronomical practices likely affects essential soil processes. More study is needed to define the effects of pre-plant tillage and amendments to soil nematode communities and Miscanthus yield over multiple growing seasons of this perennial crop.

Annual course of temperature and precipitation as proximal predictors of birds’ responses to climatic changes on the species and community level

“…According to 'Shelford's law of tolerance', all populations staying in the optimal condition do not demonstrate an unambiguous response to the ecological factors (Shelford, 1931). In contrast, switching the ecological factor from the pessimum to the optimum is commonly accompanied by the sensitive reaction of populations (Alasmary et al, 2020;Kunah et al, 2018). It is possible to assume that the species which are in an optimum zone do not appear insensitive to the variability of environmental factors.…”

Phytotechnology with Biomass Production

“…The main function is to contain the contaminated material. However, this is usually combined with adding soil amendment to reduce contaminant movement in soil (e.g., phytostabilzation of Pb contaminated military site soil using Miscanthus in combination with P amendments (Alasmary et al, 2020)). This process is used to limit the movement of contaminants with water.…”

“…Results from 2016 to 2018 showed that one-time addition of soil amendments to Pb-contaminated soil supports establishing and stabilizing Miscanthus, increasing biomass yield as well as reducing phytoavailability and bioaccessibility of Pb (as measured by physiological-based extraction test procedure developed by Ruby et al (1996) and modified by Medlin (1997)). Moreover, biosolids-treated plots showed improved soil enzyme activities, organic carbon, and microbial biomass (Alasmary et al, 2020). X-ray absorption spectroscopy results indicated pyro morphite, Pb associated with Fe minerals, and Pb adsorbed to humic acid were the dominant Pb species in P-amended and nonamended soils (Unpublished data, Alasmary and Hettiarachchi).…”

Optimization of the Micromycete Cultivation Process � Basics of Growth Regulators and Biotesting Their Growth- Stimulating Activity Concerning to Miscanthus Giganteus

“…Технологічне вдосконалення фітотехнологій ґрунтується на застосуванні різних агротехнічних, агрохімічних та біотехнологічних заходів (Verma et al, 2016;Alasmary et al, 2020;). При вирощуванні міскантусу на чорноземі типовому найвищі показники біопродуктивності рослин були отримані за комбінованої обробки рістстимулювальними біопрепаратами Квантум Голд та Вимпел-К: після проведення дворазової позакореневої обробки та обприскуванням під час вегетації (Katelevsky, 2020).…”