Yingzhi Gao

Northeast Normal University · Institute of Grassland Science

Atmospheric nitrogen (N) deposition is composed of both inorganic N (IN) and organic N (ON), and these sources of N may exhibit different impacts on ecosystems. However, our understanding of the impacts of N deposition is largely based on experimental gradients of INs or more rarely ONs. Thus, the effects of N deposition on ecosystem productivity a...

Macroinvertebrates are sensitive to environmental disturbances, however, the effects of human activities on macroinvertebrate community structures and functional traits in glacier-fed streams are concerning. To elucidate the effects of horse, cattle and sheep grazing, hot spring scenic development, and historic iron ore mine development on macroinv...

Glacier-fed streams are one of the environments most sensitive to global climate change. However, the effects of the freezing–thawing process on benthic macroinvertebrate communities in different habitats of glacier-fed streams are unclear. In this paper, we investigated benthic macroinvertebrates in riffles and pools of a glacier-fed stream in Xin...

Numerous studies have highlighted the roles of nutrient availability and fluctuations therein for invasion success of alien plants. Many others also highlighted the role of herbivores in invasion success. However, how herbivory and the level and fluctuations in nutrient availability interact in driving alien plant invasion into native communities r...

The understanding of belowground productivity restoration and biomass allocation is especially important for the restoration of salt-alkali-degraded meadows. Despite this, it remains unclear how belowground net primary productivity (BNPP) and biomass allocation respond to combined restoration measures. To assess the effects of different combined re...

Higher ecosystem nitrogen (N) inputs resulting from human activities often suppress soil microbial biomass and respiration, thereby altering biogeochemical cycling. Soil acidification and carbon (C) limitation may drive these microbial responses, yet their relative importance remains elusive, which limits our understanding of the longer-term effect...

AimsMowing is a common management practice in grassland ecosystems. However, how mowing affects fine root dynamics remains poorly explored.MethodsA field experiment was conducted to study how mowing influences root dynamics in artificial and natural grasslands for three consecutive years with root-window method.ResultsRoot production among the trea...

Background Clonal integration can improve the performance of the rhizome plants, it remains unclear whether plants clonal integration strategy is different under contrasting clipping and saline-alkali homogeneous and heterogeneous environments. Leymus chinensis is a clonal grass native to the Songnen grassland where heavy grazing and patchy saline-...

Numerous studies have tested the fluctuating resource hypothesis and highlighted the role of nutrient availability and fluctuations therein for invasion success of alien plants. Others have tested the enemy-release hypothesis and highlighted the role of herbivores in invasion success. However, how herbivory and the level and fluctuations in nutrien...

Root contact and plasticity facilitate nitrogen fixation and transfer in intercrops

More than 80% of land plant species benefit from symbiotic partnerships with arbuscular mycorrhizal (AM) fungi, which assist in nutrient acquisition and enhance the ability of host plants to adapt to environmental constraints. Host-generated plasma membrane-residing receptor-like kinases and the intracellular α/β-hydrolase DWARF14-LIKE, a putative...

Leymus chinensis, a dominant species in the Songnen Plain of northeast China, has a strong ability to resist grazing and tolerate saline-alkali stress. Compensatory growth is a positive response of plants, when subjected to grazing or clipping stress; however, little information is available on how plant nitrogen allocation strategies affect compen...

Belowground nitrogen (N) transfer from legumes to non-legumes provides an important N source for crop yield and N utilization. However, whether root contact facilitates N transfer and the extent to which N transfer contributes to crop productivity and N utilization have not been clarified. In our study, two-year rain shelter experiments were conduc...

Aims Cereal can stimulate legume N fixation through competition for soil mineral N. In addition, organic acids in the rhizosphere can mobilize external nutrients, which may help nodulation. However, how much NO3⁻ and NH4⁺ competition and organic acids in the rhizosphere of intercropped crops contribute to N fixation remains unclear and requires stu...

Aims To investigate the relative contributions of pH, organic anions concentration, and phosphatase activity to rhizosphere soil phosphorus availability and crop phosphorus uptake in polycultures. Methods A field experiment was conducted for three consecutive years in a split-plot design with main plots treated with two phosphorus levels and subpl...

Key Message Nitrogen addition leads to large increases in shoot growth but limited increases in root growth and reductions in mycorrhizal colonization of Sorbus pohuashanensis and Acanthopanax sessiliflorus. Abstract Soil in the cultivated fields of Changbai Mountain region of China is rich in phosphorus (P) and deficient in nitrogen (N) for most...

Aims Mycorrhizae and root exudates have been considered the two important pathways for nitrogen (N) transfer from legume to non-legume plants. The present study aimed to investigate contribution of the relative importance of arbuscular mycorrhizal fungi and root exudates in short-term N transfer. Methods A field experiment was conducted to explore...

Soil salinisation and overgrazing are two important factors limiting plant growth in the Songnen Grassland, Northeast China. Leymus chinensis, a dominant rhizomatous grass, resists grazing and tolerates saline–alkali stress. However, its adaptive mechanisms to the dual effects of grazing and saline–alkali stress remain largely unknown. A two-factor...

Aims To investigate whether legume-dominated cereal/legume intercropping could facilitate phosphorus acquisition and yield enhancement via changes in root morphology and distribution. Methods A field experiment was conducted for two consecutive years in a split-plot design with main plots treated with two phosphorus levels and subplots treated wit...

Nitrogen (N) enrichment often increases aboveground net primary productivity (ANPP) of the ecosystem, but it is unclear if belowground net primary productivity (BNPP) track responses of ANPP. Moreover, the frequency of N inputs may affect primary productivity but is rarely studied. To assess the response patterns of above‐ and below‐ground producti...

This study presents evidence that strigolactones (SLs) promote defense against devastating rice blast fungal pathogen Magnaporthe oryzae. Impairment in either SL-biosynthetic dwarf17 (d17) or -signaling (d14) led to increased susceptibility towards M. oryzae. Comparative transcriptome profiling of the SL-signaling d14 mutant and WT plants revealed...

The species composition of macroinvertebrate communities is sensitive to environmental changes. However, the influence of human activity over seasons on the functional characteristics of macroinvertebrate communities is poorly understood. To elucidate the effects of agriculture-induced environmental changes on stream ecosystems in cold regions, we...

Suboptimal phosphorus availability is a primary constraint to plant growth on earth. We tested the hypothesis that maize (Zea mays) genotypes with large crown root number (CN) will have shallower rooting depth and improved phosphorus (P) acquisition from low-P soils. Maize recombinant inbred lines with contrasting CN were evaluated under suboptimal...

Plant pathogens represent a huge threat to world food security, affecting both crop production and quality. Although significant progress has been made in improving plant immunity by expressing key, defense-related genes and proteins from different species in transgenic crops, a challenge remains for molecular breeders and biotechnologists to succe...

Coconut shell based biochar was irradiated by UV light of wavelength 365 nm to investigate the performance of biochar forrestoration of Cd contaminated soil.The isothermal adsorption experiment was showed the MBC-16 h had the best adsorption performance and it was up to 67.46 mg·kg⁻¹. The Cd repair test was conducted to investigate the effect of mo...

The improvement of productivity and soil organic matter is a central issue for the restoration of degraded land. Belowground net primary productivity (BNPP) is a major source of soil organic matter. Therefore, understanding BNPP dynamics is crucial to improving our knowledge of belowground C allocation and storage in grasslands. However, how tillag...

Peatland restoration has been attracting increasing attention and implementation since large areas of peatlands in China have been degraded or reclaimed to cropland in recent decades. However, the length of time for cultivated peatland to be restored to natural climax level in terms of vegetation remained unknown. A field experiment was conducted t...

Soil salinization and overgrazing are two main factors limiting animal husbandry in the Songnen Grassland.Leymus chinensis is a dominant rhizome grass, resistant to grazing as well as tolerant to salt stress. Foliar labeled with ¹⁵N-urea was used to study the nitrogen allocation strategy and compensatory growth response to clipping under saline-alk...

Biochars converted from pyrolysis of walnut shell and coconut shell were used as an alternative adsorbent for adsorbing volatile organic compounds (VOCs). Biochars were characterized by Elemental analysis, Fourier transform infrared spectra, Boehm titration and specific surface area and porosity analyzer. And the adsorption behaviors of benzene and...

In this study we test the hypothesis that maize genotypes with reduced crown root number (CN) will have greater root depth and improved water acquisition from drying soil. Maize recombinant inbred lines with contrasting CN were evaluated under water stress in greenhouse mesocosms and field rainout shelters. CN varied from 25 to 62 among genotypes....

Since large areas of peatlands in China have been degraded or reclaimed to cropland in recent decades, the conversion of these croplands to wetlands and the restoration of degraded peatlands by means of engineering have been attracting increasing attention. Hydrologic mediation and plantation of dominant peatland species were implemented to determi...

Ecosystem is the most complete basic structure and functional unit for the research of ecology and other branches, so ecosystem restoration is the basis of different levels of ecological restoration research, and the research and practice of ecological restoration should take ecosystem as the basic object. The theme for the International Conference...

The Songnen grassland is one of the grasslands in China characterized by concentrated heterogeneous patches of saline-alkaline soils. However, our understanding of how these patchy structures develop and how biochemical factors change within patches is limited. Thus, three representative semi-vegetated patches were selected and analyzed for soil el...

The Songnen grassland is one of the grasslands in China characterized by concentrated heterogeneous patches of saline-alkaline soils. However, our understanding of how these patchy structures develop and how biochemical factors change within patches is limited. Thus, three representative semi-vegetated patches were selected and analyzed for soil el...

Given the growing challenges to food and eco-environmental security as well as sustainable development of animal husbandry in the farming and pastoral areas of northeast China, it is crucial to identify advantageous intercropping modes and some constraints limiting its popularization. In order to assess the performance of various intercropping mode...

Songnen Meadow Steppe, which is in northeast China, is increasingly affected by global warming and incremental increases in atmospheric nitrogen deposition. However, the responses of nitrogen (N) and phosphorus (P) in steppe soil, and of the coupling mechanism between them, to the dual effects of global warming and N deposition are still unknown. I...

The analyses of plant leaf traits that strongly influence aboveground net primary production (ANPP) are indispensable for understanding the process of plant biomass formation. However, there are few studies that have attempted to relate patterns of ANPP under contrasting management practices to plant leaf-level traits. To assess how leaf traits aff...

Water use efficiency (WUE) is a key indicator to assess ecosystem adaptation to water stress. Rain use efficiency (RUE) is usually used as a proxy for WUE due to lack of transpiration data. Furthermore, RUE based on aboveground primary productivity (RUEANPP) is used to evaluate whole plant water use because root production data is often missing as...

Increasing grazing pressure and climate change affect nitrogen (N) dynamics of grassland ecosystems in the Eurasian steppe belt with unclear consequences for future delivery of essential services such as forage production, C sequestration, and diversity conservation. The identification of key processes responsive to grazing is crucial to optimize g...

For large areas of Inner Mongolian semi-arid grasslands, as for many regions of the Eurasian steppe belt, substantial land degradation was reported as a consequence of excessive overgrazing during the last decades. Nitrogen is considered as a key element for ecosystem functions and therefore, a comprehensive analysis of the system's N balance and c...

In semi-arid grassland ecosystems, soil biogeochemical processes are controlled by seasonal and inter-annual rainfall variation and temperature, which may override the long-term impact of grazers on N availability and N dynamics. In a three-year (2004–2006) case study of an Inner Mongolian grassland, we analysed time-integrated (ion-exchange resins...

Land use has a significant impact on spatial patterns of soil moisture, particularly in sensitive and poorly managed regions. This study evaluated the relative importance of soil, vegetation and topography in controlling the spatial moisture patterns in a grazed semi-arid steppe of Inner Mongolia. Five fields were investigated during 2004–2006: two...

Productivity of semiarid grasslands is affected by soil water and nutrient availability, with water controlling net primary production under dry conditions and soil nutrients constraining biomass production under wet conditions. In order to investigate limitations on plants by the response of root-shoot biomass allocation to water and nitrogen (N)...

Overgrazing is a major cause of grassland degradation in semi-arid regions. To evaluate how soil water and heat fluxes respond to grazing, investigations on soil, plant and meteorological parameters were conducted at four sites with different grazing intensities through three growing periods (2004–2006) in a steppe ecosystem of Inner Mongolia. The...

Based on the observed data in monitored drainage areas and GIS spatial analysis tools, watershed basic database of Shitoukoumen Reservoir Basin was built. The multivariate analysis and redundancy analysis (RDA) were used to analyze the spatial and temporal variations of water quality, identify the key environmental factors and their patterns influe...

Carbohydrates are the main energy materials for plant metabolic activities. Enough carbohydrates stored in roots are necessary for plant re-growth, its tolerance against environmental stress, and the maintenance of grassland ecosystem stability. This paper summarized the influences of grazing, nitrogen fertilization, salt stress, drought, low tempe...

Productivity of semiarid grasslands is primarily limited by seasonal rainfall amount and becomes increasingly limited by nutrient availability under wet conditions. Interactive effects of water and N availability on grassland productivity and parameters related to water use were studied on a grassland site in Inner Mongolia, China, in a 2-factorial...

Overgrazing increasingly affects large areas of Inner Mongolian semi-arid grasslands. Consequences for ecosystem functions and, in particular, for the decomposition as a key process of ecosystem carbon (C) and nitrogen (N) cycling are still unclear.We studied the effects of grazing on shoot and root decomposition with the litter bag method in a lon...

Leaf area index (LAI) is a key variable functionally related to plant biomass production. Accurate estimation of LAI is important for monitoring vegetation dynamics, and LAI information is essentially required for the prediction of microclimate and various biophysical processes within and below canopy. The traditional, direct and destructive method...

The root system of permanent grasslands is of outstanding importance for resource acquisition. Particularly under semi-arid conditions, the acquisition of water and nutrients is highly variable during the vegetation growth period and between years. Additionally, grazing is repeatedly disturbing the functional equilibrium between the root system and...

Few studies have considered interactive effects of grazing and drought on species composition and the relative contribution of species to total biomass, although it is important to understand the short-term dynamics and community succession in grazed ecosystems. We monitored species diversity and relative biomass contribution at one site protected...

Two species, Artemisia frigida Willd. (C-3, semishrub, and dominant on overgrazed sites) and Cleistogenes squarrosa (Trin.) Keng (C-4, perennial bunchgrass, and dominant or codominant on moderately grazed sites) were studied to determine the effects of defoliation, nitrogen (N) availability, competition, and their interactions on growth, biomass, a...

The accelerating extinction rate of plant species and its effect on ecosystem functioning is a hotly debated topic in ecological research. Most research projects concerning the relationship between species diversity and productivity have been conducted in artificial plant communities, with only a few in natural ecosystems. In this study we examined...

The relative competitive ability of Artemisia frigida Willd. (C3, semi-shrub) and Cleistogenes squarrosa (Trin.) Keng (C4, perennial bunchgrass), grown in a greenhouse, was studied under three nitrogen fertilizer levels, three defoliation intensities and five competitive replacement series in a factorial arrangement. Relative yield total and the re...

In this paper, the detailed morphology of Prorocentrum donghaiense Lu from both field samples and cultures was examined, and a taxonomic comparison was made between P. donghaiense and some related Prorocentrum spp. using morphological and molecular data and other published information. There were distinct differences among these species in morpholo...

There was little information available about the nutrient release synchrony with plant demand at the different stocking rate in the XINLI River Basin, Inner Mongolia, especially nitrogen. The seasonal variations of different soil nitrogen fractions (TN, NO3--N, NH4+-N, IN and Micro-N) in different soil layers were investigated at different grazing...

The effects of grazing on physical properties (bulk density, water infiltration), chemical properties (soil organic matter, nitrogen) and soil microbes of grassland soils were reviewed based on published literature. The effects of grazing on soil properties were inconsistent, because of the complexity of the soil system, time lagging after disturba...

A tmo spheric concent rat ions of greenhouse gases have increased dramat ically since the beginning of indust rial revo lut ion due to human act ivit ies such as fo ssil fuel combust ion and land2use change. Because of the increasing atmo spheric concent rat ions of greenhouse gases and their greenhouse effect, a recent IPCC repo rt has p redicted...