Paddycrusts: interfacial bioregulators of heavy metal transport

Overview

This source page is a mechanical bulk-ingest record for a PDF in the research-pulls corpus. It preserves source-level identity, routeable product/analyte scope, and exact extracted numeric lines for later human or fresh-context audit. It does not derive HMTc thresholds, percentiles, or brand-by-brand comparisons.

Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

• 17% exceed agricultural safety thresholds for at least one metal (5, 6). Cadmium (Cd)
• low (~1%) but spatially concentrated in southern and southwestern China and South See the funding table on p. 12.
• complexation of metal ions (30–32). Meanwhile, PC microorganisms can modulate local
• tion to stable cell–particle adhesion (38). As communities establish, EPS forms a three-
• in periphyton were sourced almost equally from soil and overlying water (42% vs38%),
• (64%) rather than soil (10%). Stochastic processes (e.g., dispersal limitation) appear
• of 62–90% for dissolved nitrogen and~55–99% for phosphorus, highlighting potential
• provide high densities of deprotonatable functional groups (75). Carboxyl, hydroxyl,
• fraction of Cd associated with Fe–Mn oxides can increase to approximately 55%,
• fluidized-bed biofilm reactors have achieved>80%Pb removal within 3 h, enabled by
• represent only~9% of the total Pb, with most Pb associated with Fe–Mn oxide miner­
• 21). Meanwhile, within the underlying soil/PC matrix, enhanced organiccarbon inputs
• impacts on As/Cd speciation and mobility in Table 1.
• TABLE 1 Microbial and plant functional mechanisms regulating metal(loid) mobility and ecological risk in PC systemsa
• Cd and As (Fig. 3). Practically, PCs are most predictable for Cd when EPS production and
• supply (77). Under suitable field conditions, PC biomass has been reported to increase
• agronomic context (Table 2). In solution systems, PCs exhibited direct removal capacity
• for both Cd and As, with Cd removal reaching up to 74% at an initial concentration of
• 19.5 µg L⁻¹ (24). For As, removal efficiency can reach 78% at 3.5 mg L⁻¹, and PC treat­
• (MC) showed higher Cd removal (~44%) than conventional PCs (~30%) at 15.3 µg L⁻¹ Cd
• Pot experiments have generally supported robust Cd mitigation in rice (Table 2),
• showing reported decreases in plant Cd accumulation of 41–74% across soils containing
• TABLE 2 Removal and fate control of cadmium and arsenic by PCs: a multi-scale evidence summary from solution to field studies
• Solution Cd in water:19.5 µg L⁻¹ PC The highest Cd removal rate reached 74% (24)
• As in water:1.5, 3.5 mg L⁻¹ PC As removal efficiency was 78% at 3.5 mg L⁻¹;this (98)
• treatment increased riceseed germination rate by 18%
• and seedling dry biomass by 103%, while decreasing As
• Cd in water:15.3 µg L⁻¹ PC/mine-originated crust The Cd removal rate was approximately 30% for PC and (79)
• Pot Cd in soil:5, 50 mg kg⁻¹ PC Cd accumulation in rice decreased by 74% (at 5 mg (21)
• Cd in soil:5, 50 mg kg⁻¹ PC Grain Cd content was reduced by more than 80% (102)
• kg⁻¹ and roots decreased by 28–33%, whereas As content
• increased by 40–60%;plant biomass increased by 34–
• As in soil:105.1 mg kg⁻¹ PC As content in rice roots increased by 48% (77)
• Field Cd in water:15.3 µg L⁻¹ PC/MC Rice Cd concentration was reduced to 0.8 µg g⁻¹ (16% (79)
• and to 0.5 µg g⁻¹ (38% decrease) with MC
• content was reduced by 36%
• Cd in soil:0.5–0.8 mg kg⁻¹ PC (suspension) A dose-dependent reduction in grain Cd (11–81%) and (102)
• an increase in yield (25–36%) were observed with
• 5–50 mg kg⁻¹ Cd, and grain Cd reductions exceeding 80% in some studies (21, 102).
• tis-dominated PCs increased Cd accumulation (25–80% in roots and60–85% in shoots)
• (28–33%) while increasing As (40–60%), and under high As contamination, PCs increased
• root As by 48% (33, 35). These findings reinforce the element-specific “Cd stabilization

Methods (brief)

• As(III) and/or methylated species (e.g., DMA) in pore and surface waters. Finally, we
• increasing total As and dimethylarsinic acid (DMA) in pore and surface waters (33, 35, 66,
• some contexts, As methylation, thereby increasing dissolved As(III)/DMA (33, 104).
• Biotransformation arsM: arsenite methylation Bradyrhizobium, Produces methylated arsenic species (DMA/ (77, 97)
• the proportions of As(III) and methylated species (e.g., DMA),which are typically more
• quantification of arsC genes in environmental samples by using real- naEE. 2022. Distribution of algae and cyanobacteria of biological soil

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• Shellfish (shrimp, crab, lobster, clams, oysters, mussels)
• Mercury
• Cadmium
• Lead
• Arsenic

Verification notes

• Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
• Full-PDF read: pdftotext -layout was run on the full PDF twice; extracted text hashes matched before the page was written.
• Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
• Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
• HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.