An exotic plant successfully invaded as a passenger driven by light availability.

Invasive exotic plant species (IEPs) are widely distributed across the globe, but whether IEPs are drivers or passengers of habitat change in the invaded spaces remains unclear. Here, we carried out a vegetation and soil survey in 2018 and two independent field experiments ( removal in 2014 and 2015, and fertilization experiment since 2012) and found that the invasive annual was at a disadvantage in light competition compared with perennial native grasses, but the successful invasion of was due to the sufficient light resources provided by the reduced coverage of the native species. Conversely, nitrogen enrichment can effectively inhibit invasion by increasing the photocompetitive advantage of the native species.

Shift in the migration trajectory of the green biomass loss barycenter in Central Asia.

Revealing the vegetation response law under drought stress has become a hot issue in global climate change research. Against the background of human beings actively responding to climate change, quantitatively revealing the change and migration laws of green biomass loss (GBL) caused by drought in historical and future periods is insufficient. In this regard, we innovatively constructed a joint kNDVI-SPEI (kernel normalized difference vegetation index and standardized precipitation evapotranspiration index) distribution based on copula theory to accurately capture GBL dynamic under various drought scenarios unlike previous studies conducted in a deterministic way.

Seed Germination Ecology of Semiparasitic Weed in Alpine Grasslands.

The semiparasitic weed Maxim. has rapidly spread in the alpine grasslands of northern China over the past twenty years and has caused serious ecological problems. In order to effectively halt the spread of this weed, a thorough understanding of the dormancy type and the seed-germination ecology of is required.

Leaf-root-soil N:P stoichiometry of ephemeral plants in a temperate desert in Central Asia.

Ephemeral plants are a crucial vegetation component in temperate deserts of Central Asia, and play an important role in biogeochemical cycle and biodiversity maintenance in desert ecosystems. However, the nitrogen (N) and phosphorus (P) status and interrelations of leaf-root-soil of ephemeral plants remain unclear. A total of 194 leaf-root-soil samples of eight ephemeral species at 37 sites in the Gurbantunggut Desert, China were collected, and then the corresponding N and P concentrations, and the N:P ratio were measured.

Characteristics and driving mechanisms of species beta diversity in desert plant communities.

Species dissimilarity (beta diversity) primarily reflects the spatio-temporal changes in the species composition of a plant community. The correlations between β diversity and environmental factors and spatial distance can be used to explain the magnitudes of environmental filtering and dispersal. However, little is known about the relative roles and importance of neutral and niche-related factors in the assemblage of plant communities with different life forms in deserts.

Comparison of dexmedetomidine with midazolam for dental surgery: A systematic review and meta-analysis.

Introduction: Dexmedetomidine and midazolam have become important approaches for the sedation of dental surgery. However, the comparison of these 2 drugs for the sedation of dental surgery has not been well established. We conduct a systematic review and meta-analysis to evaluate the efficacy of dexmedetomidine versus midazolam for dental surgery.

N:P stoichiometric changes via species turnover in arid versus saline desert environments.

Aridity and salinity have a key role in driving physiological and ecological processes in desert ecosystems. However, how community-scale foliar nutrients respond to aridity and salinity, and how these responses might vary with community composition along aridity and salinity gradients is unclear. We hypothesize that the response will be a shift in community stoichiometric values resulting from nutrient variability of shared species and unique species (site-specific species), but little research has addressed the relative contribution of either component.

Scaling the leaf nutrient resorption efficiency: Nitrogen vs phosphorus in global plants.

Nutrient resorption from senescent leaves is one essential plant nutrient strategy. Allocation of nitrogen (N) and phosphorus (P) reflects the influences of evolution and ecological processes on plant functional traits, and thus is related to functional types and environmental factors. However, we know little about the pattern among plant functional types (PFTs) and the driving factors of the allometric relationship of N resorption efficiency (NRE) against P resorption efficiency (PRE) in plant leaves (NRE ~ PRE; b, scaling exponent).

Factors that alter the relative importance of abiotic and biotic drivers on the fertile island in a desert-oasis ecotone.

Dryland vegetation forms a "fertile island effect" due to water and nutrient retention. However, there has been little research on the mechanism underlying C-, N-, P-accumulation and overall fertile island at the community level. We therefore presented the systematic investigation on this issue through the survey in desert-oasis ecotone.

The Growth and N Retention of Two Annual Desert Plants Varied Under Different Nitrogen Deposition Rates.

Nitrogen (N) partitioning between plant and soil pools is closely related to biomass accumulation and allocation, and is of great importance for quantifying the biomass dynamics and N fluxes of ecosystems, especially in low N-availability desert ecosystems. However, partitioning can differ among species even when growing in the same habitat. To better understand the variation of plant biomass allocation and N retention within ephemeral and annual species we studied the responses of (an ephemeral) and (an annual) to N addition, including plant growth, N retention by the plant and soil, and N lost to the environment using N (double-labeled NH NO (5.

Disentangling the influence of aridity and salinity on community functional and phylogenetic diversity in local dryland vegetation.

One of the key hypothesized drivers of community assembly and dynamics is environmental filtering, where environmental stress limits species migration and survival as a result of functional trait convergence. Whereas most such studies focus on large-scale variation in functional traits along a single-factor environmental gradient, the mutual effects of small-scale multiple environmental filtering remain unclear. Furthermore, it has rarely been tested whether the combined effect of aridity and salinity on local dryland vegetation constrains the patterns of functional traits and phylogenetic structures.

N-P Fertilization Inhibits Growth of Root Hemiparasite in Natural Grassland.

Fertilization has been shown to affect interactions between root hemiparasitic plants and their host plants, alleviating damage to the hosts by parasitism. However, as a majority of studies were conducted in pot cultivation, the influence of fertilizer application on root hemiparasites and the surrounding plant community in field conditions as well as relevant mechanisms remain unclear. We manipulated soil nutrient resources in a semi-arid subalpine grassland in the Tianshan Mountains, northwestern China, to explore the links between fertilization and plant community composition, productivity, survival, and growth of a weedy root hemiparasite ().

Influence of aridity and salinity on plant nutrients scales up from species to community level in a desert ecosystem.

Soil moisture and salt play key roles in regulating desert plant nutrient cycles on a local scale. However, information on the response of plant nutrient stoichiometric patterns to soil water and salt gradients is limited. Here, we assessed leaf N and P levels of 18 species of desert plants and measured the corresponding soil nutrient, water and salt concentrations, at four dry sites, five humid-saline sites and four humid-non-saline sites (reference sites) along a transect in a temperate desert in Xinjiang Province, northwest China.

Impacts of water and nitrogen addition on nitrogen recovery in Haloxylon ammodendron dominated desert ecosystems.

Desert ecosystems are likely to change in response to global climate change and nitrogen (N) deposition. The effects of increased precipitation and N deposition on plant growth and the N cycle largely depend on N allocation and N recovery efficiency in the plant-soil ecosystem, but there is limited research on this in desert ecosystems. Here we report results using double-labeled NHNO (30 and 60kgNhayr) as a tracer under ambient (no additional water addition) and enhanced precipitation (60mm water addition) in a Haloxylon ammodendron dominated ecosystem in the Gurbantunggut Desert of Northwest China.

A five-year study of the impact of nitrogen addition on methane uptake in alpine grassland.

It remains unclear how nitrogen (N) deposition affects soil methane (CH4) uptake in semiarid and arid zones. An in situ field experiment was conducted from 2010 to 2014 to systematically study the effect of various N application rates (0, 10, 30, and 90 kg N ha(-1) yr(-1)) on CH4 flux in alpine grassland in the Tianshan Mountains. No significant influence of N addition on CH4 uptake was found.

A multiyear assessment of air quality benefits from China's emerging shale gas revolution: Urumqi as a case study.

China is seeking to unlock its shale gas in order to curb its notorious urban air pollution, but robust assessment of the impact on PM2.5 pollution of replacing coal with natural gas for winter heating is lacking. Here, using a whole-city heating energy shift opportunity offered by substantial reductions in coal combustion during the heating periods in Urumqi, northwest China, we conducted a four-year study to reveal the impact of replacing coal with natural gas on the mass concentrations and chemical components of PM2.

Response of alpine grassland to elevated nitrogen deposition and water supply in China.

Species composition and productivity are influenced by water and N availability in semi-arid grasslands. To assess the effects of increased N deposition and water supply on plant species composition and productivity, two field experiments with four N addition treatments, and three N and water combination treatments were conducted in alpine grassland in the mid Tianshan mountains, northwest China. When considering N addition alone, aboveground biomass (AGB) of forbs (F(AGB)) responded less to N addition than AGB of grasses (G(AGB)).

Sulfide-driven microbial electrosynthesis.

Microbial electrosynthesis, the conversion of carbon dioxide to organic molecules using electricity, has recently been demonstrated for acetogenic microorganisms, such as Sporomusa ovata. The energy for reduction of carbon dioxide originates from the hydrolysis of water on the anode, requiring a sufficiently low potential. Here we evaluate the use of sulfide as an electron source for microbial electrosynthesis.

Responses of CH(4), CO(2) and N(2)O fluxes to increasing nitrogen deposition in alpine grassland of the Tianshan Mountains.

To assess the effects of nitrogen (N) deposition on greenhouse gas (GHG) fluxes in alpine grassland of the Tianshan Mountains in central Asia, CH(4), CO(2) and N(2)O fluxes were measured from June 2010 to May 2011. Nitrogen deposition tended to significantly increase CH(4) uptake, CO(2) and N(2)O emissions at sites receiving N addition compared with those at site without N addition during the growing season, but no significant differences were found for all sites outside the growing season. Air temperature, soil temperature and water content were the important factors that influence CO(2) and N(2)O emissions at year-round scale, indicating that increased temperature and precipitation in the future will exert greater impacts on CO(2) and N(2)O emissions in the alpine grassland.

Benthic microbial fuel cell as direct power source for an acoustic modem and seawater oxygen/temperature sensor system.

Supported by the natural potential difference between anoxic sediment and oxic seawater, benthic microbial fuel cells (BMFCs) promise to be ideal power sources for certain low-power marine sensors and communication devices. In this study a chambered BMFC with a 0.25 m(2) footprint was used to power an acoustic modem interfaced with an oceanographic sensor that measures dissolved oxygen and temperature.

[Relationships between belowground biomass of alpine grassland and environmental factors along an altitude gradient].

Taking Bayanbulak alpine grassland on the southern slope of Tianshan Mountain, Xin-jiang as test object, the relationships between belowground biomass and environmental factors along an altitude gradient were analyzed. The results showed that with increasing altitude, the below-ground biomass of alpine steppe dominated by Stipa purpurea and Festuca ovina, alpine steppe meadow dominated by Kobresia capillifolia and S. purpurea, and alpine meadow dominated by Carex stenocarpa, Alchemilla tianschanica, and K.