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Soil phosphorus (P) availability is a crucial factor determining primary productivity in terrestrial ecosystem. Plant functional traits and microbes under P‐deficient conditions can respond positively to increase soil P bioavailability. Whether and/or how the fine‐root traits (FRTs) of deep‐rooted desert species affect the rhizosphere and bulk soil community of phoD‐harbouring bacteria and thus improve the availability of soil P, however, remains unclear.We conducted a three‐year artificial outdoor pot experiment of P supply using Alhagi sparsifolia Shap. (hereafter Alhagi) to address this gap. Fine‐root samples from 1‐ and 3‐year‐old Alhagi seedlings and samples of the rhizospheres and bulk soil were collected. High‐throughput sequencing, sequential extraction and root system scanning were used to determine soil phoD‐harbouring bacteria community, Hedley‐P fractions and the FRTs.Fine‐root surface area (RSA), specific root length, foliar Mn concentration (indicating the quantities of root carboxylates that are released) and acid phosphatase (APase) activity were significantly higher in the no‐P supply compared with the high‐P supply conditions. APase activity was significantly higher by 27%, but the foliar Mn concentration was remarkably lower by 26%, in the 3‐ than the 1‐year‐old seedlings. The rhizospheric concentrations of labile P, moderately labile P, inorganic P and organic P in the no‐P supply condition were 5%, 11%, 10% and 21% higher, respectively, in the 3‐ than the 1‐year‐old seedlings. RSA and the foliar Mn concentration were dominated root predictors for the rhizospheric phoD‐harbouring bacteria community for the 1‐year‐old seedlings, whereas fine‐root P concentration was the dominated root predictor for the rhizospheric and bulk soil phoD‐harbouring bacteria communities for the 3‐year‐old seedlings. Soil water content, as the most dominant soil factor driving the variation of phoD‐harbouring bacteria community, notably could not be ignored. FRTs were the main factors that directly and positively determined rhizospheric phoD‐harbouring bacteria community and thus influenced soil P availability, but bulk soil phoD‐harbouring bacteria community were dominated by inorganic P concentration. The importance of fine‐root morphological traits to soil P availability gradually increased as the plants grew.Overall, our results emphasize the significance of rhizospheric phoD‐harbouring bacteria determined by the effect of FRTs on the bioavailability of soil P. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Coastal‐wetlands play a crucial role as carbon (C) reservoirs on Earth due to their C pool composition and functional sink, making them significant for mitigating global climate change. However, due to the development and utilization of wetland resources, many wetlands have been transformed into other land‐use types. The current study focuses on the alterations in soil organic‐C (SOC) in coastal‐wetlands following reclamation into aquaculture ponds. We conducted sampling at 11 different coastal‐wetlands along the tropical to temperate regions of the China coast. Each site included two community types, one with solely native species (Suaeda salsa, Phragmites australis and Mangroves) and the other with an adjacent reclaimed aquaculture pond. Across these 11 locations we compared SOC stock, active OC fractions, and soil physicochemical properties between coastal wetlands and aquaculture ponds. We observed that different soil uses, sampling sites, and their interaction had significant effects on SOC and its stock (p <.05). Reclamation significantly declined SOC concentration at depths of 0–15 cm and 15–30 cm by 35.5% and 30.3%, respectively, and also decreased SOC stock at 0–15 cm and 15–30 cm depths by 29.1% and 37.9%, respectively. Similar trends were evident for SOC stock, labile organic‐C, dissolved organic‐C and microbial biomass organic‐C concentrations (p <.05), indicating soil C‐destabilization and losses from soil following conversion. Soils in aquaculture ponds exhibited higher bulk density (BD; 11.3%) and lower levels of salinity (61.0%), soil water content (SWC; 11.7%), total nitrogen (TN) concentration (23.8%) and available‐nitrogen concentration (37.7%; p <.05) than coastal‐wetlands. Redundancy‐analysis revealed that pH, BD and TN concentration were the key variables most linked with temporal variations in SOC fractions and stock between two land use types. This study provides a theoretical basis for the rational utilization and management of wetland resources, the achievement of an environment‐friendly society, and the preservation of multiple service functions within wetland ecosystems. [ABSTRACT FROM AUTHOR]

Understanding the influence of afforestation on soil microorganisms, the major drivers of soil processes, is essential for maintaining soil health and sustainability. However, in a desert‐oasis ecotone, variations in the microbial community along shrub afforestation years remain unclear. We conducted a metagenomic analysis to study the temporal changes in microbial community structure in 0–100 cm soil following 3‐, 7‐, and 10‐year afforestation of Tamarix ramosissima Ledeb. on the southern edge of the Taklimakan Desert. Compared to the unreclaimed desert land, in 3‐year or 7‐year stands, soil organic carbon (SOC), nitrate nitrogen, available phosphorus and potassium (AK) contents significantly increased on average by 60%, 852%, 72%, and 299%, respectively. Soil archaeal and bacterial community composition were significantly affected by afforestation; their α‐diversity increased on average by 5.9% and 11.1%, respectively, after afforestation, showing a unimodal pattern along afforestation years. In contrast, fungal α‐diversity and community composition did not show significant variation over the afforestation period. The influence of AK outweighed that of SOC and other nutrients on soil microbial community composition. These findings suggest that T. ramosissima afforestation in the desert‐oasis ecotone has significant impacts on the community composition and α‐diversity of archaea and bacteria, but not fungi, by modifying soil physicochemical properties. This research provides valuable implications for soil management and microbial processes related to the afforestation of salt‐secreting shrubs. [ABSTRACT FROM AUTHOR]

Summary: Deserts represent key carbon reservoirs, yet as these systems are threatened this has implications for biodiversity and climate change. This review focuses on how these changes affect desert ecosystems, particularly plant root systems and their impact on carbon and mineral nutrient stocks. Desert plants have diverse root architectures shaped by water acquisition strategies, affecting plant biomass and overall carbon and nutrient stocks. Climate change can disrupt desert plant communities, with droughts impacting both shallow and deep‐rooted plants as groundwater levels fluctuate. Vegetation management practices, like grazing, significantly influence plant communities, soil composition, root microorganisms, biomass, and nutrient stocks. Shallow‐rooted plants are particularly susceptible to climate change and human interference. To safeguard desert ecosystems, understanding root architecture and deep soil layers is crucial. Implementing strategic management practices such as reducing grazing pressure, maintaining moderate harvesting levels, and adopting moderate fertilization can help preserve plant–soil systems. Employing socio‐ecological approaches for community restoration enhances carbon and nutrient retention, limits desert expansion, and reduces CO2 emissions. This review underscores the importance of investigating belowground plant processes and their role in shaping desert landscapes, emphasizing the urgent need for a comprehensive understanding of desert ecosystems. [ABSTRACT FROM AUTHOR]

Drylands, comprising semi‐arid, arid, and hyperarid regions, cover approximately 41% of the Earth's land surface and have expanded considerably in recent decades. Even under more optimistic scenarios, such as limiting global temperature rise to 1.5°C by 2100, semi‐arid lands may increase by up to 38%. This study provides an overview of the state‐of‐the‐art regarding changing aridity in arid regions, with a specific focus on its effects on the accumulation and availability of carbon (C), nitrogen (N), and phosphorus (P) in plant–soil systems. Additionally, we summarized the impacts of rising aridity on biodiversity, service provisioning, and feedback effects on climate change across scales. The expansion of arid ecosystems is linked to a decline in C and nutrient stocks, plant community biomass and diversity, thereby diminishing the capacity for recovery and maintaining adequate water‐use efficiency by plants and microbes. Prolonged drought led to a −3.3% reduction in soil organic carbon (SOC) content (based on 148 drought‐manipulation studies), a −8.7% decrease in plant litter input, a −13.0% decline in absolute litter decomposition, and a −5.7% decrease in litter decomposition rate. Moreover, a substantial positive feedback loop with global warming exists, primarily due to increased albedo. The loss of critical ecosystem services, including food production capacity and water resources, poses a severe challenge to the inhabitants of these regions. Increased aridity reduces SOC, nutrient, and water content. Aridity expansion and intensification exacerbate socio‐economic disparities between economically rich and least developed countries, with significant opportunities for improvement through substantial investments in infrastructure and technology. By 2100, half the world's landmass may become dryland, characterized by severe conditions marked by limited C, N, and P resources, water scarcity, and substantial loss of native species biodiversity. These conditions pose formidable challenges for maintaining essential services, impacting human well‐being and raising complex global and regional socio‐political challenges. [ABSTRACT FROM AUTHOR]

Due to the increasing impact of worldwide environmental changes, temperature stress has become a major factor resulting in crop yield losses. The discovery of temperature‐stress‐responsive protein‐coding genes has made significant progress in understanding plants' complex stress response systems involving microRNAs (miRNAs). The miRNAs are triggered by heat or cold, thus confirming their significant functional role in cold or heat tolerance. Such dependable recommendations significantly broaden our understanding of the regulatory role of miRNAs in plant stress responses. This article presents novel perspectives on the substantial roles of plant miRNAs in responding to and acclimatizing to heat and cold stress. It comprehensively elaborates on miRNAs responsive to temperature stress, their regulatory mechanisms, and their targeted functions in plants. Additionally, the article investigates how miRNAs contribute to safeguarding plant reproductive tissues, mitigating damage caused by reactive oxygen species, modulating heat shock proteins, transcription factors, and phytohormones in the context of temperature stress. The conclusion outlines potential avenues for future research, highlighting the utilization of miRNAs and their regulatory functions to develop economically vital crops with enhanced tolerance to temperature stress, thereby ensuring future food security. [ABSTRACT FROM AUTHOR]

Biogeochemical niche (BN) hypothesis aims to relate species/genotype elemental composition with its niche based on the fact that different elements are involved differentially in distinct plant functions. We here test the BN hypothesis through the analysis of the 10 foliar elemental concentrations and 20 functional‐morphological of 60 tree species in a French Guiana tropical forest. We observed strong legacy (phylogenic + species) signals in the species‐specific foliar elemental composition (elementome) and, for the first time, provide empirical evidence for a relationship between species‐specific foliar elementome and functional traits. Our study thus supports the BN hypothesis and confirms the general niche segregation process through which the species‐specific use of bio‐elements drives the high levels of α‐diversity in this tropical forest. We show that the simple analysis of foliar elementomes may be used to test for BNs of co‐occurring species in highly diverse ecosystems, such as tropical rainforests. Although cause and effect mechanisms of leaf functional and morphological traits in species‐specific use of bio‐elements require confirmation, we posit the hypothesis that divergences in functional‐morphological niches and species‐specific biogeochemical use are likely to have co‐evolved. [ABSTRACT FROM AUTHOR]

Traits of leaves and fine roots are expected to predict the responses and adaptation of plants to their environments. Whether and how fine‐root traits (FRTs) are associated with the allocation of foliar phosphorus (P) fractions of desert species in water‐ and P‐poor environments, however, remains unclear. We exposed seedlings of Alhagi sparsifolia Shap. (hereafter Alhagi) treated with two water and four P‐supply levels for three years in open‐air pot experiments and measured the concentrations of foliar P fractions, foliar traits, and FRTs. The allocation proportion of foliar nucleic acid‐P and acid phosphatase (APase) activity of fine roots were significantly higher by 45.94 and 53.3% in drought and no‐P treatments relative to well‐watered and high‐P treatments, whereas foliar metabolic‐P and structural‐P were significantly lower by 3.70 and 5.26%. Allocation proportions of foliar structural‐P and residual‐P were positively correlated with fine‐root P (FRP) concentration, but nucleic acid‐P concentration was negatively correlated with FRP concentration. A tradeoff was found between the allocation proportion to all foliar P fractions relative to the FRP concentration, fine‐root APase activity, and amounts of carboxylates, followed by fine‐root morphological traits. The requirement for a link between the aboveground and underground tissues of Alhagi was generally higher in the drought than the well‐watered treatment. Altering FRTs and the allocation of P to foliar nucleic acid‐P were two coupled strategies of Alhagi under conditions of drought and/or low‐P. These results advance our understanding of the strategies for allocating foliar P by mediating FRTs in drought and P‐poor environments. [ABSTRACT FROM AUTHOR]

Plants are subjected to salt and drought stresses concurrently but our knowledge about the effects of combined stress on plants is limited, especially on halophytes. We aim to study if some diverse drought and salt tolerance traits in halophyte may explain their tolerance to salinity and drought stresses, individual and in combination, and identify key traits that influence growth under such stress conditions. Here, the halophyte Halogeton glomeratus was grown under control, single or combinations of 60 days drought and salt treatments, and morphophysiological responses were tested. Our results showed that drought, salinity, and combination of these two stressors decreased plant growth (shoot height, root length, and biomass), leaf photosynthetic pigments content (chlorophyll a, b, a + b and carotenoids), gas exchange parameters (Net photosynthesis rate [PN], transpiration rate [E], stomatal conductance [gs]), and water potential (ψw), and the decreases were more prominent under combined drought and salinity treatment compared with these two stressors individually performed. Similarly, combined drought and salinity treatment induced more severe oxidative stress as indicated by more hydrogen peroxide (H2O2) and malondialdehyde (MDA) accumulated. Nevertheless, H. glomeratus is equipped with specific mechanisms to protect itself against drought and salt stresses, including upregulation of superoxide dismutases (SOD; EC 1.15.1.1) and catalase (CAT; EC 1.11.1.6) activities and accumulation of osmoprotectants (Na+, Cl−, and soluble sugar). Our results indicated that photosynthetic pigments content, gas exchange parameters, water potential, APX activity, CAT activity, soluble sugar, H2O2, and MDA are valuable screening criteria for drought and salt, alone or combined, and provide the tolerant assessment of H. glomeratus. [ABSTRACT FROM AUTHOR]

Drip irrigation is a useful practice to enhance water and fertilizer nitrogen (N) use efficiency. However, the use of drip irrigation to mitigate nitrous oxide (N2O) emissions in agricultural systems globally is uncertain. Here, we performed a global meta‐analysis of 485 field measurements of N2O emissions from 74 peer‐reviewed publications prior to March 2021, to quantify the fertilizer‐induced N2O emission factor (EF) of drip irrigation and examine the influencing factors of climate, crop, soil properties, and source and rate of fertilizer N application. The results showed that drip irrigation reduced (p < 0.05) N2O emissions by 32% and 46% compared to furrow and sprinkler irrigation systems, respectively. The overall average EF with drip irrigation was 0.35%, being two‐thirds lower than the IPCC Tier I default value of 1% (kg N2O‐N/kg added fertilizer N). The EF was not significantly affected by climate, crop, soil texture, soil organic carbon content, and pH. The EF was also not significantly (p > 0.05) affected by synthetic N fertilizer source despite a lower numerical value with enhanced efficiency than conventional fertilizers. The EF increased significantly (p < 0.001) with N addition rate in a binomial distribution. Using the IPCC default EF overestimated N2O emissions inventories for drip‐irrigated cropping systems by 7614 and 13,091 Mg per year for China and the globe, respectively. These results indicate that drip irrigation should be recommended as an essential N2O mitigation strategy for irrigated crop production. [ABSTRACT FROM AUTHOR]

The terminal branch orders of plant root systems have been proposed as short-lived 'ephemeral' modules specialized for resource absorption. The occurrence of ephemeral root modules has so far only been reported for a temperate tree species and it is unclear if the concept also applies to other woody (shrub, tree) and herb species., Fine roots of 12 perennial dicotyledonous herb, shrub and tree species were monitored for two growing seasons using a branch-order classification, sequential sampling and rhizotrons in the Taklamakan desert., Two root modules existed in all three plant functional groups. Among the first five branch orders, the first two (perennial herbs, shrubs) or three (trees) root orders were ephemeral and had a primary anatomical structure, high nitrogen (N) concentrations, high respiration rates and very short life spans of 1-4 months, whereas the last two branch orders in all functional groups were perennial, with thicker diameters, no or collapsed cortex, distinct secondary growth, low N concentrations, low respiration rates, but much longer life spans., Ephemeral, short-lived root modules and long-lived, persistent root modules seem to be a general feature across many plant functional groups and could represent a basic root system design. [ABSTRACT FROM AUTHOR]

Desertification is among the most severe global environmental and the socio-economic problems in the world. This paper is a first attempt to link scientific research to national policymaking on desertification in China. We aim to trace scientific research findings in the national policies and strategies of desertification prevention in China. One example is the large-scale plantation programme in the dust source region threatening Beijing and Tianjin since 1998. It has been suggested that the recent increased forest cover due to plantations in North China has helped reduce dust storm emissions and contributed to mitigating dust storm weather in Beijing and Tianjin. Reforestation/afforestation policy remains in the Chinese national environmental strategies for the new national forestation programme (2011-2020). Overgrazing during recent decades has been blamed for land degradation and desertification in Northwest China by many scholars. Small field experiments prove that vegetation in desertified/degraded land could recover if isolated from human activities. Since 1998, natural recovery has become one powerful national force to prevent land desertification and recover natural vegetation. One example is selected at Cele County, Xinjiang Uygur Autonomous Region to showcase how vegetation could thrive at large scale in natural arid and semi-arid climate if isolated from human intervention. The plantation project has pushed the stakeholders to better understand their negative impact on the environment, especially the overgrazing behaviour. After that, the household income and living level have also been significantly enhanced; however, it is not clear whether the project induced labour migration. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study investigates the utility of plant δ¹3C natural labeling in predicting the impacts of environmental shifts on carbon cycling within ecosystems, particularly focusing on paddy fields treated with maize (Zea mays L.) residues and biochar. Specifically, it examines how soil δ¹3C and the sources of soil organic carbon (SOC), respond in paddy fields (which cultivate C3 plants like rice) when amended with maize residues, maize biochar, and silica‐enriched biochar (derived from C4 plants). Conducted in the Fuzhou paddy fields, the experiment included control groups and treatment groups with maize residue (4 t ha⁻¹), maize biochar (4 t ha⁻¹), and silicon‐modified maize biochar (4 t ha⁻¹) during both the early and late rice growth periods. The results indicate that all soil treatments increased soil δ¹3C. The application of maize residues notably affected the δ¹3C of the upper soil profile (0–15 cm) differently from the deeper layers (15–30 cm), and it increased soil organic C more than biochar or silicon‐modified maize biochar. Soil available P (AP) and pH emerged as significant factors linking δ¹3C, influencing rice yield through changes in soil physicochemical properties. Unlike maize residues, which reduced rice yields, applications of biochar and silicon‐modified maize biochar increased rice yields. The latter, which was particularly effective in lowering SOC decomposition rates and addressing rice's silica needs, emerged as the preferred option. The study highlights maize biochar and silicon‐modified maize biochar as sustainable alternatives to maize residues for rice cultivation, enhancing soil fertility, carbon pool stability, and yields. [ABSTRACT FROM AUTHOR]