Drought mediates Sphagnum defense response to herbivory.

Premise: The expected concomitant increase in multiple stressors such as herbivory and drought may threaten peatland ecosystems. How Sphagnum, the ecological engineers of peatlands, responds to combined stressors remains largely unexplored. Here we aimed to clarify resource allocations in Sphagnum during concomitant herbivory and drought.

Diatom cell-size composition as a novel tool for quantitative estimates of the water table in peatlands.

Diatom cell-size composition is an indicator of aquatic environmental changes but has been rarely investigated, especially in semi-terrestrial peatlands. In this study, both taxonomic composition and cell-size composition of diatoms were analysed in 41 samples from two montane peatlands, northeastern China. Redundancy analyses revealed that diatom taxonomic composition was significantly related to the depth to the water table (DWT) and Ca, while cell-size composition was significantly associated with DWT and Si.

Smoke promotes germination of peatland bryophyte spores.

Northern peatlands are globally important carbon stores. With increasing fire frequency, the re-establishment of bryophytes becomes crucial for their carbon sequestration. Smoke-responsive germination is a common trait of seeds in fire-prone ecosystems but has not been demonstrated in bryophytes.

Does Shift in Vegetation Abundance After Nitrogen and Phosphorus Additions Play a Key Role in Regulating Fungal Community Structure in a Northern Peatland?

Soil fungal communities are key players in biogeochemical processes of peatlands, which are important carbon stocks globally. Although it has been elucidated that fungi are susceptible to environmental changes, little is known about the intricate and interactive effect of long-term nitrogen (N) and phosphorus (P) enrichment on fungal community structure in northern peatlands. In this study, we compared a short- (2 years) with a long-term (10 years) fertilization experiment in a peatland complex in northeastern China to assess how N and/or P additions influence fungal community structure.

Induced defense and its cost in two bryophyte species.

Premise: Current knowledge about defense strategies in plants under herbivore pressure is predominantly based on vascular plants. Bryophytes are rarely consumed by herbivores since they have ample secondary metabolites. However, it is unknown whether bryophytes have induced defenses against herbivory and whether there is a trade-off between growth and defense in bryophytes.

The variations of surface wetness recorded by multi-proxies in Yuanchi peatland of the Changbai Mountains from 1962 to 2008.

Surface wetness of Yuanchi peatland in the Changbai Mountains were reconstructed by comprehensive analysis on plant residue, testate amoeba and humification, using the age-depth model established with AMS C and Cs dating methods. The response of surface wetness to climate change was addressed. Results showed that plant residues in the top 50 cm of peat sequence were dominated by mosses.

Hydrological variation recorded in a subalpine peatland of Northeast Asia since the Little Ice Age and its possible driving mechanisms.

Hydrological characteristics since the Little Ice Age (LIA) could provide a good reference for current climate analysis and future climate prediction. However, the hydrological variation since the LIA and its driving mechanisms in Northeast Asia remain unclear, which has severely restricted our understanding on the past, present and future hydroclimate changes in these regions. Here we reconstruct the hydrological dynamics over the past 700 years using samples from the Hani peatland a subalpine peatland of Changbai Mountains to reveal these issues.

Inhibition or Facilitation? Contrasted Inter-Specific Interactions in under Laboratory and Field Conditions.

In a natural environment, plants usually interact with their neighbors predominantly through resource competition, allelopathy, and facilitation. The occurrence of the positive effect of allelopathy between peat mosses ( L.) is rare, but it has been observed in a field experiment.

[Responses of the germinability of Sphagnum spores in peat to drainage in Baijianghe Peatland, China].

Drainage severely changes the environment and ecological process in peatlands, but how does it affect the germinability of Sphagnum spores in peat remains unclear. In this study, we took two peat cores from a near-pristine stand dominated by Sphagnum and a drained stand dominated by dwarf shrubs in Baijianghe Peatland in the Changbai Mountains as experimental materials. Those peat cores were cut into slices.

Diatom-based water-table reconstruction in Sphagnum peatlands of northeastern China.

Peatlands are important ecosystems for biodiversity conservation, global carbon cycling and water storage. Hydrological changes due to climate variability have accelerated the degradation of global and regional ecosystem services of peatlands. Diatoms are important producers and bioindicators in wetlands, but comprehensive diatom-based inference models for palaeoenvironmental reconstruction in peatlands are scarce.

Estimating Chlorophyll Content of Leafy Green Vegetables from Adaxial and Abaxial Reflectance.

As a primary pigment of leafy green vegetables, chlorophyll plays a major role in indicating vegetable growth status. The application of hyperspectral remote sensing reflectance offers a quick and nondestructive method to estimate the chlorophyll content of vegetables. Reflectance of adaxial and abaxial leaf surfaces from three common leafy green vegetables: Pakchoi var.

The development of Hani peatland in the Changbai mountains (NE China) and its response to the variations of the East Asian summer monsoon.

The past ecosystem responses to climate variability makes it possible to view the sensitivity of ecosystems to climate-forced state shifts. To test the hypothesis that the development of peatland in the Changbai Mountains responds to the variability of the East Asian summer monsoon (EASM), the developmental history of the Hani peatland was investigated based on peat basal ages. It can be concluded that the development of Hani peatland is the paludification.

[Simulated study on the effects of smoke on Sphagnum spore germination].

Moderate smoke could facilitate seed germination, but its effects on bryophyte spore germination is still unknown. Here, we analyzed the effects of smoke, capsule size and storage time on the spore germination of Sphagnum squarrosum and S. magellanicum, with the capsules of which being collected from two peatlands of the Changbai Mountains.

Mercury and arsenic in the surface peat soils of the Changbai Mountains, northeastern China: distribution, environmental controls, sources, and ecological risk assessment.

The potential toxic risk of mercury (Hg) and arsenic (As) in the soils of mining regions and other artificially disturbed lands receives considerable research attention. However, limited investigation has been conducted into the surface soils of natural globally distributed ecosystems, for example peatlands. In this study, we examine the distribution, controlling factors, sources, and potential ecological risks of Hg and As in 96 samples from 42 peatlands in the Changbai Mountains of northeastern China.

Degradation of polycyclic aromatic hydrocarbons (PAHs) during Sphagnum litters decay.

The dynamics of polycyclic aromatic hydrocarbon (PAH) degradation in Sphagnum litters and the decomposition of the litters were investigated. PAH concentration decreased to approximately half of the initial concentration as Sphagnum litters decayed. The initial PAH concentration was 489.

Variations in diatom communities at genus and species levels in peatlands (central China) linked to microhabitats and environmental factors.

Peatlands are a specialized type of organic wetlands, fulfilling essential roles as global carbon sinks, headwaters of rivers and biodiversity hotspots. Despite their importance, peatlands are being lost at an alarming rate due to human disturbance and climatic variability. Both the scientific and regulatory communities have focused considerable attention on developing tools for assessing environmental changes in peatlands.

Is there 'anther-anther interference' within a flower? Evidences from one-by-one stamen movement in an insect-pollinated plant.

The selective pressure imposed by maximizing male fitness (pollen dispersal) in shaping floral structures is increasingly recognized and emphasized in current plant sciences. To maximize male fitness, many flowers bear a group of stamens with temporally separated anther dehiscence that prolongs presentation of pollen grains. Such an advantage, however, may come with a cost resulting from interference of pollen removal by the dehisced anthers.

[Effects of shading on two Sphagnum species growth and their interactions].

Taking Sphagnum palustre and S. fallax as test materials, this paper studied their growth and interactions under shading. In monoculture, shading promoted the height growth of S.

Direct and interaction-mediated effects of environmental changes on peatland bryophytes.

Ecosystem processes of northern peatlands are largely governed by the vitality and species composition in the bryophyte layer, and may be affected by global warming and eutrophication. In a factorial experiment in northeast China, we tested the effects of raised levels of nitrogen (0, 1 and 2 g m(-2) year(-1)), phosphorus (0, 0.1 and 0.

[Niches of seven bryophyte species in Hani peat land of Changbai Mountains].

Based on field investigation and by using Levins and Pianka formula, the niches of seven bryophyte species in Hani Peatland of Changbai Mountains were studied. The results showed that the average niche breadth in nine environmental factors (total nitrogen, total phosphorous, K+ and Ca2+ in peat, pH,and electrical conductivity of surface water, tree coverage, shrub coverage, and depth to water table) of the seven species decreased in the order of Aulacomnium palustre > Sphagnum fallax > S. magellanicum > S.

[Research advances on interactions among bryophytes].

This paper summarized the present research status and advances on the intra- and interspecific positive interaction, intra- and inter-specific competition, niche, and coexistence of bryophytes. Bryophytes are generally the dominant plants in harsh environments, and there is a trade-off between their water retention and light and nutrient resource availability. Because of the lesser importance of competition in harsh environments, the positive interaction among bryophytes is common, but the intra- and inter-specific competition among bryophytes and the competition between bryophytes and vascular plants are not rare.

[Reconstruction of Polytrichum juniperinum population dynamics in a mire of China].

By using 'history reconstruction method', this paper studied the dynamics of two Polytrichum juniperinum populations with and without sporophytes. The population with sporophyte production experienced a dynamic process from increase to stabilization, while that without sporophyte production experienced a process from increase to decrease. Before 2003, both the increase rate and the birth rate of two populations decreased continuously, with the death rate showing the tendency from decrease to a continuous increase.