[Effect of enhanced silicate minerals weathering on carbon sequestration by plant-soil systems in rice fields].

Successive crop harvest results in soil silicon (Si) loss, which constantly reduces soil available Si. Agricultural measures that can increase the availability of soil Si are in urgent need in agroecosystems. Enhanced weathering of silicate minerals can effectively replenish soil Si, which will promote plant uptake of Si, formation of plant phytolith occluded carbon (PhytOC), and the sequestration of atmospheric CO.

Risk of Traumatic Intracranial Hemorrhage After Stroke: A Nationwide Population-Based Cohort Study in Taiwan.

Background: Stroke and traumatic intracranial hemorrhage (tICH) are major causes of disability worldwide, with stroke exerting significant negative effects on the brain, potentially elevating tICH risk. In this study, we investigated tICH risk in stroke survivors.

Methods And Results: Using relevant data (2017-2019) from Taiwan's National Health Insurance Research Database, we conducted a population-based retrospective cohort study.

[Approach and evidence-based study of provincial-level eco-economic development planning].

The development of ecological economy is one of the core elements of the ecological civilization system and an essential means to optimize the social-ecological systems. The key to developing ecological economy lies in preparing the development plan to realize concrete implementation. Given the objective and realistic demand for the development of ecological economy, it is critically needed to propose the approach of eco-economic planning and conduct empirical research.

[NO and N emission characteristics from maize and greenhouse vegetable soils in Northern China].

To explore NO and N emissions from upland soils after nitrogen fertilizer application, a 60-day aerobic incubation experiment (25 ℃,80% water-filled pore space) using the N tracing method was conducted to quantify the N transformation, NO and N emissions from maize soils from four sites (Harbin, Shenyang, Luancheng and Shouguang) and vegetable soils from two sites (Shen-yang and Shouguang), with urea being applied at 167 mg N·kg to simulate the field application rate of 200 kg N·hm. The results showed that for the four sites with maize soils, the cumulative emission of NO was in the order of Shouguang (20 mg N·kg) > Luancheng (14 mg N·kg) > Shenyang (5 mg N·kg) > Harbin (0.5 mg N·kg) and the cumulative N emission was in the order of Luancheng (176 mg N·kg) > Shenyang (106 mg N·kg) > Shouguang (75 mg N·kg) > Harbin (12 mg N·kg).

Generalist Taxa Shape Fungal Community Structure in Cropping Ecosystems.

Fungi regulate nutrient cycling, decomposition, symbiosis, and pathogenicity in cropland soils. However, the relative importance of generalist and specialist taxa in structuring soil fungal community remains largely unresolved. We hypothesized that generalist fungi, which are adaptable to various environmental conditions, could potentially dominate the community and become the basis for fungal coexisting networks in cropping systems.

[Effects of soil moisture on microbial processes of soil nitrogen gases production under anaerobic conditions].

Gaseous nitrogen (N) emission [nitric oxide (NO), nitrous oxide (NO), and nitrogen (N)] is an important pathway of soil N loss. Nitrification and denitrification are the main processes of gaseous N production in soil. However, the contribution of heterotrophic nitrification, co-denitrification, and anammox to gaseous N production remains uncertain.

[Concurrent Collection of Ammonia Gas and Aerosol Ammonium in Urban Beijing During National Celebration Days Utilizing an Acid-Coated Honeycomb Denuder in Combination with a Filter System].

Since 2013, the Chinese government implemented the Air Pollution Prevention and Control Action Plan. As a result, the atmospheric concentrations of sulfate reduced significantly, whereas the nitrate concentrations remain relatively high due to the excess of ammonia (NH). To date, there is no official observation network monitoring NH concentrations in China.

[Source Apportionment of Atmospheric Ammonia: Sensitivity Test Based on Stable Isotope Analysis in R Language].

Ammonia (NH) is an important precursor of fine particles and nitrogen deposition. It is critical to identify and quantify the sources of NH before the implementation of a mitigation strategy. Stable isotope analysis in R (SIAR) has potential with regard to the source apportionment of NH, but its reliability is closely related to the signatures (N-NH) of emission sources.

Large-scale patterns of soil antibiotic resistome in Chinese croplands.

Soil is a vital reservoir of antibiotic resistance genes (ARGs), but we still know little about their distribution in cropland soils and the main driving forces. Here we performed an investigation for ARGs patterns in 105 cropland soils (planted with maize, peanut or soybean) along a 2, 200 km transect in China using high-throughput quantitative PCR approaches. Totally, 204 ARGs were detected, with a higher diversity found in central China than that in northeast and south China.

Multiple factors drive the abundance and diversity of the diazotrophic community in typical farmland soils of China.

Biological nitrogen fixation plays an important role in nitrogen cycling by transferring atmospheric N2 to plant-available N in the soil. However, the diazotrophic activity and distribution in different types of soils remain to be further explored. In this study, 152 upland soils were sampled to examine the diazotrophic abundance, nitrogenase activity, diversity and community composition by quantitative polymerase chain reaction, acetylene reduction assay and the MiSeq sequencing of nifH genes, respectively.

Protist communities are more sensitive to nitrogen fertilization than other microorganisms in diverse agricultural soils.

Background: Agricultural food production is at the base of food and fodder, with fertilization having fundamentally and continuously increased crop yield over the last decades. The performance of crops is intimately tied to their microbiome as they together form holobionts. The importance of the microbiome for plant performance is, however, notoriously ignored in agricultural systems as fertilization disconnects the dependency of plants for often plant-beneficial microbial processes.

[Isotope analysis of ammonium and nitrate: A review on measured methods and their application].

In the past several decades, a variety of methods have been developed for measuring the isotopic composition of ammonium (δN) and nitrate (δN and δO). This review summarized the advantages and disadvantages of these methods. Nowadays, the most popular method for measu-ring δN of ammonium is the combined hypobromite (BrO) and hydroxylamine (NHOH) me-thod, while for δN and δO of nitrate is the denitrifier method and the sodium azide (NaN) me-thod.

Thinning effect on photosynthesis depends on needle ages in a Chinese fir (Cunninghamia lanceolata) plantation.

Canopies in evergreen coniferous plantations often consist of various-aged needles. However, the effect of needle age on the photosynthetic responses to thinning remains ambiguous. Photosynthetic responses of different-aged needles to thinning were investigated in a Chinese fir (Cunninghamia lanceolata) plantation.

Mixing effects of understory plant litter on decomposition and nutrient release of tree litter in two plantations in Northeast China.

Understory vegetation plays a crucial role in carbon and nutrient cycling in forest ecosystems; however, it is not clear how understory species affect tree litter decomposition and nutrient dynamics. In this study, we examined the impacts of understory litter on the decomposition and nutrient release of tree litter both in a pine (Pinus sylvestris var. mongolica) and a poplar (Populus × xiaozhuanica) plantation in Northeast China.

Variations in nitrogen-15 natural abundance of plant and soil systems in four remote tropical rainforests, southern China.

The foliar stable N isotope ratio (δ(15)N) can provide integrated information on ecosystem N cycling. Here we present the δ(15)N of plant and soil in four remote typical tropical rainforests (one primary and three secondary) of southern China. We aimed to examine if (1) foliar δ(15)N in the study forests is negative, as observed in other tropical and subtropical sites in eastern Asia; (2) variation in δ(15)N among different species is smaller compared to that in many N-limited temperate and boreal ecosystems; and (3) the primary forest is more N rich than the younger secondary forests and therefore is more (15)N enriched.

Preliminary insights into δ15N and δ18O of nitrate in natural mosses: a new application of the denitrifier method.

Natural mosses have been employed as reactive and accumulative indicators of atmospheric pollutants. Using the denitrifier method, the concentration, δ(15)N and δ(18)O of moss nitrate (NO(3)(-)) were measured to elucidate the sources of NO(3)(-) trapped in natural mosses. Oven drying at 55-70 °C, not lyophilization, was recommended to dry mosses for NO(3)(-) analyses.

Dynamics of soil inorganic nitrogen and their responses to nitrogen additions in three subtropical forests, south China.

Three forests with different historical land-use, forest age, and species assemblages in subtropical China were selected to evaluate current soil N status and investigate the responses of soil inorganic N dynamics to monthly ammonium nitrate additions. Results showed that the mature monsoon evergreen broadleaved forest that has been protected for more than 400 years exhibited an advanced soil N status than the pine (Pinus massoniana) and pine-broadleaf mixed forests, both originated from the 1930's clear-cut and pine plantation. Mature forests had greater extractable inorganic N pool, lower N retention capacity, higher inorganic N leaching, and higher soil C/N ratios.