Both subsoiling tillage (ST) and ridge and furrow rainfall harvesting (RF) are widely implemented and play an important role in boosting wheat productivity. However, information about the effects of ST coupled with RF during the summer fallow season on wheat productivity and environmental issues remains limited. This study aims to explore the effects of ST coupled with RF on water harvesting, wheat productivity-yield traits, water and nutrient use efficiency and quality, and soil nitrate-N residue in dryland winter wheat-summer fallow rotation at the intersection of southern Loess Plateau and western Huang-Huai-Hai Plain in China in 2018-2022. Three tillage practices-deep plowing with straw turnover (PTST), subsoiling with straw mulching (STSM), and STSM coupled with RF (SRFSM)-are conducted during the summer fallow season. The results indicated that tillage practices during the summer fallow season significantly impacted wheat productivity and soil nitrate-N residue. Compared to PTST, STSM significantly enhanced rainfall fallow efficiency and water use efficiency by 7.0% and 14.2%, respectively, as well as N, P, and K uptake efficiency by 16.9%, 16.2%, and 15.3%, and thus increased grain yield by 14.3% and improved most parameters of protein components and processing quality, albeit with an increase in nitrate-N residue in the 0- to 300-cm soil depth by 12.5%. SRFSM, in turn, led to a further increase in water storage at sowing, resulting in an increase of water use efficiency by 6.8%, as well as N, P, and K uptake efficiency and K internal efficiency by 11.8%, 10.4%, 8.8%, and 4.7%, thereby significantly promoting grain yield by 10.2%, and improving the contents of all the protein components and enhancing the processing quality in grain, and simultaneously reducing the nitrate-N residue in the 0- to 300-cm soil layer by 16.1%, compared to STSM. In essence, this study posits that employing subsoiling coupled with ridge-furrow rainfall harvesting (SRFSM) during the summer fallow season is a promising strategy for enhancing wheat yield, efficiency, and quality, and simultaneously reducing soil nitrate-N residue within the dryland summer fallow-winter wheat rotation system.

Organic fertilizer substitution is an effective measure for increasing both the quantity and quality of wheat grain while reducing chemical fertilizer input. However, the effects of reducing nitrogen (N) fertilizer combined with organic fertilizer substitution on grain yield, grain protein content and protein yield, plant N accumulation and translocation, N use efficiency, soil fertility, N apparent surplus and nitrate-N residue in rain-fed drought-prone areas remains limited. In this study, field experiments were conducted over four consecutive seasons (2019-2023) at two sites with four treatments: zero N application (ZN), farmer N application (FN), reduced 20% N of FN (RN), and organic fertilizer substituting 20% N of RN (OSN). The results showed that compared with the ZN treatment, the FN, RN and OSN treatments increased grain yield and its components, grain protein content and protein yield, aboveground N accumulation at the anthesis and maturity stages, pre-anthesis N translocation, post-anthesis N accumulation, N use efficiency, soil fertility. Compared with RN and FN, OSN increased grain yield by 17.12% and 15.03%, grain protein yield by 3.31% and 17.15%, grain N accumulation by 17.78% and 15.58%, and N harvest index by 2.63% and 4.45% averaged across years and sites, respectively. Moreover, OSN increased the contents of organic matter, total N, available P and available K in both 0-20 and 20-40 cm soil layers, decreased N apparent surplus and nitrate-N residue in 0-100 cm, and pH in both 0-20 and 20-40 cm soil layer. Fundamentally, this study suggests that integrating a 20% reduction N from conventional farmer practices with the utilization of organic fertilizer to replace 20% of the chemical N fertilizer (OSN) represents an effective strategy. This approach shows promise in enhancing wheat grain yield, grain protein yield, and N use efficiency. Additionally, it supports the improvement of soil fertility while simultaneously reducing soil nitrate-N residues and the apparent surplus of N in rain-fed drought-prone regions.

Monoculture is widely practiced to increase crop productivity, but long-term adaptation has drawbacks as it increases the depletion of soil nutrients and reduces soil quality, especially in dryland areas. Conversion from traditional maize monoculture to intercropping improves sustainable production. However, maize/peanut intercropping, especially rotation of planting strips impacts of maize/peanut intercropping in dryland on carbon (C) budgets and economic benefits remain unclear. In this study, a 5-year field experiment was conducted to evaluate the influence of maize/peanut intercropping with rotation of planting strips on soil health, indirect CO2-eq greenhouse gas emissions, and ecosystem C inputs. Four intercropping treatments viz. maize monoculture, peanut monoculture, maize/peanut intercropping, and maize/peanut rotation-intercropping were tested from 2018 to 2022. Maize/peanut rotation intercropping significantly improved the land equivalent ratio followed by intercropping and monoculture. Rotation-intercropping also improved economic benefits over intercropping and monoculture which were mainly associated with increased peanut yield where the border rows contributed the maximum, followed by the middle rows. Moreover, rotation-intercropping significantly increased the soil organic C and nitrogen (N) content. Rotation-intercropping decreased indirect CO2-eq greenhouse gas emissions and ecosystem C inputs by 3.11% and 18.04%, whereas increased ecosystem C outputs and net ecosystem C budget by 10.38% and 29.14%, respectively, over the average of monoculture. On average for intercropping and monoculture, rotation-intercropping increased ecosystem C emission efficiency for economic benefits by 51.94% and 227.27% in 2021 and 2022, respectively, showing the highest C utilization efficiency than other treatments. In the long run, maize/peanut rotation-intercropping can be practiced in dryland agriculture to achieve sustainable agriculture goals.

It is generally accepted that sulfur can passivate the bioavailability of heavy metals in soil, but it is not clear whether high sulfur in cadmium (Cd) and chromium (Cr) contaminated soil has negative effect on soil microbial community and ecological function. In this study, total sulfur (TS) inhibited the Chao 1, Shannon, Phylogenetic diversity (Pd) of bacterial and Pd of fungi in slightly contaminated soil by Cd and Cr around pyrite. TS, total potassium, pH, total chromium, total cadmium, total nitrogen, soil organic matter were the predominant factors for soil microbial community; the contribution of TS in shaping bacterial and fungal communities ranked at first and fifth, respectively. Compared with the low sulfur group, the abundance of sulfur sensitive microorganisms Gemmatimonas, Pseudolabrys, MND1, and Schizothecium were decreased by 68.79-97.22% (p < 0.01) at high sulfur one; the carbon fixation, nitrogen cycling, phosphorus cycling and resistance genes abundance were significantly lower (p < 0.01) at the latter. Such variations were strongly and closely correlated to the suppression of energy metabolism (M00009, M00011, M00086) and carbon fixation (M00173, M00376) functional module genes abundance in the high sulfur group. Collectively, high sulfur significantly suppressed the abundances of functional microorganisms and functional genes in slightly contaminated soil with Cd and Cr, possibly through inhibition of energy metabolism and carbon fixation of functional microorganisms. This study provided new insights into the environmental behavior of sulfur in slightly contaminated soil with Cd and Cr.

UNASSIGNED: Dryland ecosystems face serious threats from climate change. Establishing the spatial pattern of ecosystem multifunctionality, maximum height and the correlation of biodiversity patterns with climate change is important for understanding changes in complex ecosystem processes. However, the understanding of their relationships across large spatial areas remains limited in drylands.
UNASSIGNED: Accordingly, this study examined the spatial patterns of ecosystem multifunctionality, maximum height and considered a set of potential environmental drivers by investigating natural shrub communities in Northwest China.
UNASSIGNED: We found that the ecosystem multifunctionality (EMF) and maximum height of shrub communities were both affected by longitude, which was positively correlated with the precipitation gradient. Specifically, the EMF was driven by high precipitation seasonality, and the maximum height was driven by high precipitation stability during the growing season. Among the multiple biodiversity predictors, species beta diversity (SD-beta) is the most common in determining EMF, although this relationship is weak.
UNASSIGNED: Unlike tree life form, we did not observe biodiversity-maximum height relationships in shrub communities. Based on these results, we suggest that more attention should be paid to the climatical fluctuations mediated biodiversity mechanisms, which are tightly correlated with ecosystem\'s service capacity and resistance capacity under a rapid climate change scenario in the future.

Climate and human activities are the basic driving forces that control and influence the spatial distribution and change of vegetation. Using trend analysis, the Hurst index, correlation analysis, the Moran index, path analysis, residual analysis, and other methods, the effects of human activities and climate factors on vegetation change were analyzed. The results show that: (1) The research area\'s normalized difference vegetation index (NDVI) exhibited a substantial upward trend from 2001 to 2020, increasing at a rate of 0.003/a, and the vegetation cover was generally healthy. The generally constant NDVI region made up 78.45% of the entire area, and the grassland, cultivated land, and forest land showed the most visible NDVI aggregation features. (2) The Vegetation is mainly promoted by water and heat, particularly precipitation, have a major impact on plants, with the direct influence of precipitation on vegetation growth being much greater than the indirect effect through the temperature. (3) The trend of NDVI residuals showed obvious spatial variability, presenting a distribution characteristic of high in the south and low in the north. The results of this study can provide a basis for the scientific layout of ecological protection and restoration projects in the Yinshanbeilu area.

Biological soil crusts (biocrusts) are widely distributed in global drylands and have multiple significant roles in regulating dryland soil and ecosystem multifunctionality. However, maps of their distribution over large spatial scales are uncommon and sometimes unreliable, because our current remote sensing technology is unable to efficiently discriminate between biocrusts and vascular plants or even bare soil across different ecosystem and soil types. The lack of biocrust spatial data may limit our ability to detect risks to dryland function or key tipping points. Here, we indirectly mapped biocrust distribution in China\'s drylands using spatial prediction modeling, based on a set of occurrences of biocrusts (379 in total) and high-resolution soil and environmental data. The results showed that biocrusts currently cover 13.9 % of China\'s drylands (or 5.7 % of China\'s total area), with moss-, lichen-, and cyanobacterial-dominated biocrusts each occupying 5.7 % to 10.7 % of the region. Biocrust distribution is mainly determined by soil properties (soil type and contents of gravel and nitrogen), aridity stress, and altitude. Their most favorable habitat is arenosols with low contents of gravel and nitrogen, in climate with a drought index of 0.54 and an altitude of about 500 m. By 2050, climate change will lead to a 5.5 %-9.0 % reduction in biocrust cover. Lichen biocrusts exhibit a high vulnerability to climate change, with potential reductions of up to 19.0 % in coverage. Biocrust cover loss is primarily caused by the combined effects of the elevated temperature and increased precipitation. Our study provides the first high-resolution (250 × 250 m) map of biocrust distribution in China\'s drylands and offers a reliable approach for mapping regional or global biocrust colonization. We suggest incorporating biocrusts into Earth system models to identify their significant impact on global or regional-scale processes under climate change.

Drylands with fragile socio-ecological systems are vulnerable to soil erosion. China\'s drylands face the dual threat of water (WAE) and wind erosion (WIE). To mitigate soil erosion in drylands, China has implemented numerous ecological restoration measures. However, whether vegetation and soil have different effects on soil erodibility for water erosion (soil erodibility, K) and wind erosion (soil erodible fraction, EF) in drylands is unclear, hindering decision makers to develop suitable ecological restoration strategies. Here, we conducted a large-scale belt transect survey to explore the spatial variation of K and EF in China\'s drylands, and examined the linear and nolinear effects of aridity (aridity index), vegetation (fractional vegetation cover and below-ground biomass), and soil properties (bulk density, total nitrogen, and total phosphorus) on K and EF. The results showed in China\'s drylands that the K ranges from 0.02 to 0.07, with high values recorded in the northern Loess Plateau and the eastern Inner Mongolia Plateau. The EF ranges from 0.26 to 0.98, and shows longitudinal zonation with higher values in the east and lower values in the west. Aridity has a negative linear effect on K and an inverse U-shaped nonlinear effect on EF. Aridity can affect K and EF by suppressing vegetation growth and disrupting soil properties. However, K and EF had different responses to some vegetation and soil variables. K and EF had opposite relationships with soil bulk density, and EF was significantly affected by fractional vegetation cover, while K was not. Overall, the effects of aridity and soil properties on soil erodibility were more pronounced than those from vegetation, whose effect on soil erodibility was limited. This study provides relevant information to support reducing soil water and wind erosion by highlighting the hotspot areas of soil erodibility, relevant for implementing vegetation restoration and soil conservation measures in drylands.

Wheat (Triticum aestivum L.) is a staple crop worldwide, and its yield has improved since the green revolution, which was attributed to chemical nitrogen (N) fertilizer application. An experiment was conducted to set seven nitrogen application levels of N0, N90, N120, N150, N180, N210 and N240 kg ha-1 before sowing. The results showed that grain yield under the nitrogen rate of N210 kg ha-1 was significantly increase the water intake during jointing to anthesis, Soil water storage of dryland wheat in fallow period was higher than water consumption in jointing stage and the leaf area index at anthesis, the tiller percentage rate, the jointing-anthesis, and nitrogen accumulation were closely related to yield and its components. Nitrogen fertiliser rate N150 kg ha-1 significantly increased dry matter buildup from jointing to flowering in dryland wheat compared to N fertiliser rate N210 kg ha-1. The rise of nitrogen application rate, there were no significant variance in nitrogen accumulation of Stem + leaf sheath and cob + glume at maturity, respectively. N fertiliser rate N210 kg ha-1 compared to N180 kg ha-1 significantly reduced grain gliadin content in dryland wheat, respectively. Wheat crops under N210 kg ha-1 could achieve both high NUE and grain yield simultaneously with only moderate N fertilizer in South Shanxi, China.

Dryland ecosystems experience seasonal cycles of severe drought and moderate precipitation. Desert plants may develop symbiotic relationships with root endophytic microbes to survive under the repeated wet and extremely dry conditions. Although community coalescence has been found in many systems, the colonization by functional microbes and its relationship to seasonal transitions in arid regions are not well understood. Here we examined root endophytic microbial taxa, and their traits in relation to their root colonization, during the dry and wet seasons in a hot desert of the southwestern United States. We used high-throughput DNA sequencing of 16S rRNA and internal transcribed spacer gene profiling of five desert shrubs, and analyzed the seasonal change in endophytic microbial lineages. Goodness of fit to the neutral community model in relationship to microbial traits was evaluated. In summer, Actinobacteria and Bacteroidia increased, although this was not genus-specific. For fungi, Glomeraceae selectively increased in summer. In winter, Gram-negative bacterial genera, including those capable of nitrogen fixation and plant growth promotion, increased. Neutral model analysis revealed a strong stochastic influence on endophytic bacteria but a weak effect for fungi, especially in summer. The taxa with higher frequency than that predicted by neutral model shared environmental adaptability and symbiotic traits, whereas the frequency of pathogenic fungi was at or under the predicted value. These results suggest that community assembly of bacteria and fungi is regulated differently. The bacterial community was affected by stochastic and deterministic processes via bacterial response to drought (response trait), beneficial effect on plants (effect trait), and likely stable mutualistic interactions with plants suggested by the frequency of nodule bacteria. For fungi, mycorrhizal fungi were selected by plants in summer. The regulation of beneficial microbes by plants in both dry and wet seasons suggests the presence of plant-soil positive feedback in this natural desert ecosystem.