Scott X. Chang

University of Alberta | UAlberta · Department of Renewable Resources

Altered precipitation regimes as a result of global climate change have significant implications for ecosystem processes, such as the decomposition of litter, a vital process in carbon (C) and nutrient cycling in terrestrial ecosystems. However, the effects of altered precipitation regimes on litter decomposition across humid and arid biomes remain...

Background and aims Greenspace soils are a critical component of urban ecosystems, playing an essential role in delivering ecosystem services. Soil organic carbon (SOC) in these areas show considerable variability and uncertainty due to urbanization. However, it remains poorly understood how urbanization intensity and vegetation type affect greensp...

Nitrate (NO3⁻) leaching from nitrogen (N) fertilized soils is a significant global concern, affecting both the environment and public health. However, substantial uncertainties and variabilities in NO3⁻ leaching factors (LFs) among regions or crops impede accurate assessments of NO3⁻ leaching. Here we synthesize 2500 field observations worldwide an...

Pursuing sustainable agricultural production necessitates innovative approaches to enhance nutrient use efficiency and mitigate the environmental impact of fertilizer use in cropping systems. Biochar-based controlled-release fertilizers (BCRFs) have emerged as a promising solution to address these challenges. This paper reviews BCRF production meth...

Converting waste plastics into renewable energy through zeolite-catalytic pyrolysis is a promising strategy for combating plastic pollution and supplanting conventional fossil fuels, thereby facilitating emission mitigation. However, it is still challenging to comprehensively decipherer this conversion process and screen efficient catalysts for div...

Ectomycorrhizal (ECM) fungi comprise a large proportion of the living and dead microbial‐derived soil carbon (C) pool in boreal forests. Because soil nitrogen (N) and C cycles are closely interlinked, shifts in N availability and subsequent effects on dead fungal mass (“necromass”) may influence C storage in soils. Several mechanisms could underlie...

Soil microorganisms transform plant‐derived C (carbon) into particulate organic C (POC) and mineral‐associated C (MAOC) pools. While microbial carbon use efficiency (CUE) is widely recognized in current biogeochemical models as a key predictor of soil organic carbon (SOC) storage, large‐scale empirical evidence is limited. In this study, we propose...

Corporation operations and other anthropogenic activities threaten global biodiversity and ecosystem services. They also raise financial risks for the sustainability of society. International organizations and initiatives have developed guidelines on the disclosure of nature-positive business practices to support the conservation of biodiversity. H...

The impact of plant litter on soil carbon (C) cycling is influenced by external nitrogen (N) deposition and plant litter chemistry. While previous research has mainly focused on inorganic N deposition and its effect on plant litter decomposition and soil C cycling, the influence of organic N remains poorly understood. In this study, we conducted a...

Anthropogenic land‐use practices influence ecosystem functions and the environment. Yet, the effect of global land‐use change on ecosystem nitrogen (N) cycling remains unquantified despite that ecosystem N cycling plays a critical role in maintaining food security. Here, we analysed 2430 paired observations globally to show that converting natural...

The application of biochar to soil is widely recognized as a promising strategy for enhancing the accumulation and stability of soil organic carbon (SOC), which is crucial in mitigating climate change. However, the influence of interactions between plants and biochar on soil microbial communities and their involvement in SOC mineralization and stab...

Forests harbor extensive biodiversity and act as a strong global carbon and nitrogen sink. Although enhancing tree diversity has been shown to mitigate climate change by sequestering more carbon and nitrogen in biomass and soils in manipulative experiments, it is still unknown how varying environmental gradients, such as gradients in resource avail...

Purpose The influence of organic amendments on the interplay among soil extracellular enzyme activities (EEAs) and their stoichiometry (EES) and nutrient availabilities, key indicators of resource limitations for soil microbes, is poorly understood. This study aims to investigate how manure compost (hereafter “manure”) and its biochar derivative af...

The rising carbon dioxide concentrations are expected to increase future rice yields. However, variations in the CO2 fertilization effect (CFE) between rice subspecies and the influence of concurrent global warming introduce uncertainty in future global rice yield projections. Here we conducted a meta-analysis of rising carbon dioxide field experim...

Drought has the most significant impact on arid grassland ecosystems. Managed grazing, including the timing and intensity of defoliation, may interact with drought to differentially affect processes related to soil organic matter decomposition. Extracellular enzyme activity (EEA) provides integrated measure of soil microbial activity which affects...

climate regions. Fully-enclosed dairy farms act as a promising option while its economic and environmental performance is poorly studied. Here, we evaluated the potential of improvement on milk yield and milk supply inequality among regions by developing fully-enclosed dairy farms throughout China, as well as their economic feasibility and environm...

Fungi play a crucial role in the utilization and storage of soil organic carbon (SOC). Biochar can potentially influence soil carbon (C) turnover by mediating extracellular electron transfer, which can be facilitated by fungi. However, the effects of biochar and soil types on the community, abundance, enzyme secretion, and necromass of fungi mediat...

Grassland soils play an important role in sequestering carbon (C) and are primarily used for livestock grazing. Grazing management can increase the amount of C stored in soils and the distribution of C in different soil fractions by altering soil microbial community structure, thereby influencing the persistence of soil C over time. Adaptive multi-...

Atmospheric nitrogen (N) deposition inevitably alters soil nutrient status, subsequently prompting plants to modify their root morphology (i.e., adopting a do-it-yourself strategy), mycorrhizal symbioses (i.e., outsourcing strategy), and root exudation (i.e., nutrient-mining strategy) linking with resource acquisition. However, how N deposition inf...

Soil metabolomics is an emerging approach for profiling diverse small molecule metabolites, i.e., metabolomes, in the soil. Soil metabolites, including fatty acids, amino acids, lipids, organic acids, sugars, and volatile organic compounds, often contain essential nutrients such as nitrogen, phosphorus, and sulfur and are directly linked to soil bi...

The effects of long-term biochar application on soil phosphorus (P) flux across the root-soil interface and its availability in the rhizosphere of rice ( Oryza sativa L) remain unclear. We used diffusive gradients in thin films (DGT), laser ablation-inductively coupled plasma mass spectrometry, and planar optode sensor techniques to characterize, i...

Background and Aims Roots are of critical importance to plants due to their role in absorbing soil water and nutrients and adapting to ever-changing environmental conditions. Grazing changes plant and soil conditions and can affect root growth and resource utilization strategies. However, it is still unclear how grazing intensity affects plant root...

One strategy to reduce CO 2 emissions from cement production is to reduce the amount of Portland cement produced by replacing it with supplementary cementitious materials (SCMs). Biochar is a potential SCM that is an eco-friendly and stable porous pyrolytic material. However, the effects of biochar addition on the performances of Portland cement co...

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both human and ecosystem health. In response, global initiatives are focusing on risk assessment...

Overbalance of ecosystems triggers global biodiversity loss and threatens the sustainability of society by emerging financial risks from the disruption of ecosystem services. Several initiatives and international organizations have developed guidelines on biodiversity conservation to support the increasing demand for the disclosure of nature-positi...

The incorporation of organic amendments, such as food waste (FW) and biochar, into soil is an established agronomic practice known for enhancing soil fertility and improving overall soil health. However, the individual and combined effects of FW and biochar on soil properties in microplastic (MP)-contaminated soil–plant systems remain poorly unders...

Climate change is increasing the frequency and severity of short-term (~1 y) drought events—the most common duration of drought—globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in t...

Amid rising energy crises and greenhouse gas (GHG) emissions, designing energy efficient, GHG mitigation and profitable conservation farming strategies are pertinent for global food security. Therefore, we tested a hypothesis that no-till with residue retaining could improve energy productivity (EP) and energy use efficiency (EUE) while mitigating...

Highly diverse exoenzymes mediate the energy flow from substrates to the multitrophic microbiota within the soil decomposer micro‐food web. Here, we used a “soil enzyme profile analysis” approach to establish a series of enzyme profile indices; those indices were hypothesized to reflect micro‐food web features. We systematically evaluated the shift...

Biochar from biomass and waste is a valuable component of various urban green infrastructures, including green roofs, permeable pavements, green walls, and green parking lots. Incorporating biochar into substrate mixtures...

Reversing land management from no-tillage to conventional tillage (tillage reversal, TR) may markedly alter soil greenhouse gas (GHG) emissions in soils with differing fertility levels. We studied the impact of TR and nitrogen (N) fertilization on CO2 (total CO2 flux and its components), N2O and CH4 fluxes, and area- and yield-scaled GHG fluxes ove...

Biochar can be used for multifunctional applications including the improvement of soil health and carbon storage, remediation of contaminated soil and water resources, mitigation of greenhouse gas emissions and odorous compounds, and feed supplementation to improve animal health. A healthy soil preserves microbial biodiversity that is effective in...

Converting natural forests to agricultural lands has been widespread globally due to increasing population and the demand for food. Phosphorus (P) is often applied to agricultural lands in excessive amounts which can saturate the natural P sorption capacity of the soil, leading to P leaching and subsequent off‐site water eutrophication. We studied...

Microplastic (MP) pollution in agricultural soils, resulting from the use of plastic mulch, compost, and sewage sludge, jeopardizes the soil microbial populations. However, the effects of MPs on soil chemical properties and microbial communities remain largely unknown. Here, we investigated the effects of different concentration levels (0, 0.1, 1,...

Advanced materials for the efficient treatment of textile wastewater need to be developed for the sustainable growth of the textile industry. In this study, graphene oxide (GO) was modified by the incorporation of natural clay (bentonite) and mixed metal oxide (copper-cobalt oxide) to produce GO-based binary and ternary composites. Two binary compo...

Deposition of atmospheric inorganic and organic nitrogen (N) may increase soil nitrous oxide (N2O) emissions. To simulate and quantify such effects in forest ecosystems, understory N application, usually directly to the soil surface, has been used. However, this approach overlooks N interception by forest canopies, resulting in overestimates of act...

Plant invasion can change soil microbial function and nitrogen (N) supply through the input of litter with different qualities and quantities, among other factors. However, the underlying mechanism for litter quality to regulate soil N mineralization via microbial function with plant invasion remains unclear. We examined the effect of litterfall wi...

Biochar has been widely recommended as an effective soil amendment for reducing nitrous oxide (N2O) emissions and nitrogen (N) leaching. However, the effects of biochar application to Lei bamboo plantations on soil N2O emissions and N leaching remain unclear. These effects on soil N2O emissions and N leaching were investigated in the present study...

The sustainability of life on Earth is under increasing threat due to human-induced climate change. This perilous change in the Earth's climate is caused by increases in carbon dioxide and other greenhouse gases in the atmosphere, primarily due to emissions associated with burning fossil fuels. Over the next two to three decades, the effects of cli...

Pulp mill biosolids (hereafter 'biosolids') could be used as an organic amendment to improve soil fertility and promote crop growth; however, it is unclear how the application of biosolids affects soil greenhouse gas emissions and the mechanisms underlying these effects. Here, we conducted a 2-year field experiment on a 6-year-old hybrid poplar pla...

Phytoliths are amorphous silica formed gradually in plant tissue, which have great potential to mitigate climate change due to their resistance to decomposition and their ability to occlude organic carbon. The accumulation of phytoliths is regulated by multiple factors. However, the factors controlling its accumulation remain unclear. Here, we inve...

Grasslands are globally abundant and provide many ecosystem services, including carbon (C) storage. While grasslands are widely subject to livestock grazing, the influence of grazing on grassland ecosystem C remains unclear. We studied the effect of long-term livestock grazing on C densities of different ecosystem components in 110 northern tempera...

Purpose The effects of nitrogen (N) deposition and leaf litter addition on soil carbon (C) cycling have been widely studied. However, soil carbon dioxide (CO2) emissions linked to N deposition, leaf litter decomposition, soil microbial biomass, and enzyme activity remain poorly understood. Therefore, the objective of this study was to investigate t...

Chromium (Cr) affects human health if it accumulates in organs to elevated concentrations. The toxicity risk of Cr in the ecosphere depends upon the dominant Cr species and their bioavailability in the lithosphere, hydrosphere, and biosphere. However, the soil-water-human nexus that controls the biogeochemical behaviour of Cr and its potential toxi...

Increasing soil carbon and nitrogen storage can help mitigate climate change and sustain soil fertility1,2. A large number of biodiversity-manipulation experiments collectively suggest that high plant diversity increases soil carbon and nitrogen stocks3,4. It remains debated, however, whether such conclusions hold in natural ecosystems5–12. Here we...

Reckless release of contaminants into the environment causes pollution in various aquatic systems on a global scale. Biochar is potentially an inexpensive and environmentally friendly adsorbent for removing contaminants from water. Ball milling has been used to enhance biochar's functionality; however, global analysis of the effect of ball milling...

One-third of the annual food produced globally is wasted and much of the food waste (FW) is unutilized; however, FW can be valorized into value-added industrial products such as biofuel, chemicals, and biomaterials. Converting FW into soil amendments such as compost, vermicompost, anaerobic digestate, biofertilizer, biochar, and engineered biochar...

Forest soil CO2 efflux (FCO2) is a crucial process in global carbon cycling; however, how FCO2 responds to disturbance regimes in different forest biomes is poorly understood. We quantified the effects of disturbance regimes on FCO2 across boreal, temperate, tropical and Mediterranean forests based on 1240 observations from 380 studies. Globally, c...

Species mixtures have been widely reported to increase aboveground productivity; however, how tree species mixtures affect root systems in natural forests remains unclear. We hypothesize that mixtures have a greater fine root length compared to single species‐dominated stands to support their greater productivity. Here, we collected monthly root im...