117 results for group: agrogeology-2


Soil remineralization and recovery of degraded areas: An experience in the tropical region

Many activities related to the expansion of food supply, energy and infrastructure result in great environmental impacts, whose most visible features are observed in the degradation of large areas. The present study demonstrates how the combined use of stonemeal technology and agroforestry systems can help to reverse such impacts, allying the recovery of degraded areas with agricultural and forest production. The study area is located in a hydroelectric reservoir affected by the siltation process and soil erosion in the hydrographic basin of the San Francisco River, Brazil. An Experimental Unit (EU) was set up in the Ecological Station of Pirapitinga ...

Co-utilization of rock dust, mineral fines and compost

This report examines the relevance and potential of techniques using rockdust to remineralize soils in Scotland. Rockdust (RD) is a generic term applied to fine materials produced as by-products of quarrying and mineral processing. The concept is concerned with making available a multitude of minerals from freshly crushed rocks that are considered by advocates not to be present in larger quantities in weathered soils. Claimed benefits include : •enhanced long term sustainable soil fertility and diverse soil biology; •multi-season effects; •enhanced plant establishment, growth and vigour; •compatibility with organic farming practices; ...

Calcium-mediated stabilisation of soil organic carbon

Soils play an essential role in the global cycling of carbon and understanding the stabilisation mechanisms behind the preservation of soil organic carbon (SOC) pools is of globally recognised significance. Until recently, research into SOC stabilisation has predominantly focused on acidic soil environments and the interactions between SOC and aluminium (Al) or iron (Fe). The interactions between SOC and calcium (Ca) have typically received less attention, with fewer studies conducted in alkaline soils. Although it has widely been established that exchangeable Ca (CaExch) positively correlates with SOC concentration and its resistance to oxidation, ...

Silicon-augmented resistance of plants to herbivorous insects: a review

Silicon (Si) is one of the most abundant elements in the earth's crust, although its essentiality in plant growth is not clearly established. However, the importance of Si as an element that is particularly beneficial for plants under a range of abiotic and biotic stresses is now beyond doubt. This paper reviews progress in exploring the benefits at two- and three-trophic levels and the underlying mechanism of Si in enhancing the resistance of host plants to herbivorous insects. Numerous studies have shown an enhanced resistance of plants to insect herbivores including folivores, borers, and phloem and xylem feeders. Silicon may act directly on insect ...

Assessing biogas digestate, pot ale, wood ash and rockdust as soil amendments: effects on soil chemistry and microbial community composition

Applying by-products as soil amendments to agricultural systems is growing in popularity. We aimed to assess the efficacy of some contemporary by-products to provide nutrients to crops as well as the potential harm of adding toxic elements to the environment. Four different by-products widely available in Northern Europe were tested for their effects on two nutrient-poor agricultural soils in terms of increasing available macro- and micro-nutrients as well as toxic elements. Assessing soil microbial community as a sensitive tool for evaluating soil quality was conducted with the focus on microbial activity, carbon metabolism and on Rhizobium/Agrobac...

Addition of a volcanic rockdust to soils has no observable effects on plant yield and nutrient status or on soil microbial activity

Rising costs and pressure on supplies of commercial mineral fertilizers and increasing markets for organically produced foods and feeds have led to a growing interest in soil amendments to supply plant nutrients. Rockdust is a by-product of quarrying and its effectiveness to supply plants with nutrients has been a contested issue and there have been no assessments of its effect on soil biota other than plants. The aim of this study was to assess the effect of a commercially-available volcanic rockdust application on crop growth and element concentrations for a wide range of macro and microelements and the response of soil microbial communities to ...

Impacts of enhanced weathering on biomass production for negative emission technologies and soil hydrology

Limiting global mean temperature changes to well below 2 ∘C likely requires a rapid and large-scale deployment of negative emission technologies (NETs). Assessments so far have shown a high potential of biomass-based terrestrial NETs, but only a few assessments have included effects of the commonly found nutrient-deficient soils on biomass production. Here, we investigate the deployment of enhanced weathering (EW) to supply nutrients to areas of afforestation–reforestation and naturally growing forests (AR) and bioenergy grasses (BG) that are deficient in phosphorus (P), besides the impacts on soil hydrology. Using stoichiometric ratios and ...

Elevated growth and biomass along temperate forest edges

Fragmentation transforms the environment along forest edges. The prevailing narrative, driven by research in tropical systems, suggests that edge environments increase tree mortality and structural degradation resulting in net decreases in ecosystem productivity. We show that, in contrast to tropical systems, temperate forest edges exhibit increased forest growth and biomass with no change in total mortality relative to the forest interior. We analyze >48,000 forest inventory plots across the north-eastern US using a quasi-experimental matching design. At forest edges adjacent to anthropogenic land covers, we report increases of 36.3% and 24.1% in ...

Trace Elements as Fertilizer Micronutrients

Trace elements are important in human, animal, and plant nutrition. One of the main sources of food for humans and animals are plants. Therefore, the effect of trace elements (optimal doses, as well as excess and deficiency) on plant growth is described. Plants use several trace elements in small quantities. In this chapter special attention is paid to boron, cobalt, copper, iodine, iron, molybdenum, manganese, selenium, zinc, silicon, nickel and chlorine as fertilizer micronutrients. The functions of each trace element are described, both with the symptoms of their deficiency and toxicity, as well as the chemical forms of that are delivered into or ...

Nitrogen in rock: Occurrences and biogeochemical implications

There is a growing interest in the role of bedrock in global nitrogen cycling and potential for increased ecosystem sensitivity to human impacts in terrains with elevated background nitrogen concentrations. Nitrogen-bearing rocks are globally distributed and comprise a potentially large pool of nitrogen in nutrient cycling that is frequently neglected because of a lack of routine analytical methods for quantification. Nitrogen in rock originates as organically bound nitrogen associated with sediment, or in thermal waters representing a mixture of sedimentary, mantle, and meteoric sources of nitrogen. Rock nitrogen concentrations range from trace ...