Leaf transcriptome analysis of a subtropical evergreen broadleaf plant, wild oil-tea camellia (Camellia oleifera), revealing candidate genes for cold acclimation

Single nucleotide polymorphism (SNP) positions in genes of Camellia oleifera. Genotypes of samples from Jinggang (JG01-04) and Lu (LS01-04) mountains are shown. (XLSX 8324 kb

Understanding Plant-Microbe Interactions for Phytoremediation of Petroleum-Polluted Soil

Plant-microbe interactions are considered to be important processes determining the efficiency of phytoremediation of petroleum pollution, however relatively little is known about how these interactions are influenced by petroleum pollution. In this experimental study using a microcosm approach, we examined how plant ecophysiological traits, soil nutrients and microbial activities were influenced by petroleum pollution in Phragmites australis, a phytoremediating species. Generally, petroleum pollution reduced plant performance, especially at early stages of plant growth. Petroleum had negative effects on the net accumulation of inorganic nitrogen from its organic forms (net nitrogen mineralization (NNM)) most likely by decreasing the inorganic nitrogen available to the plants in petroleum-polluted soils. However, abundant dissolved organic nitrogen (DON) was found in petroleum-polluted soil. In order to overcome initial deficiency of inorganic nitrogen, plants by dint of high colonization of arbuscular mycorrhizal fungi might absorb some DON for their growth in petroleum-polluted soils. In addition, through using a real-time polymerase chain reaction method, we quantified hydrocarbon-degrading bacterial traits based on their catabolic genes (i.e. alkB (alkane monooxygenase), nah (naphthalene dioxygenase) and tol (xylene monooxygenase) genes). This enumeration of target genes suggests that different hydrocarbon-degrading bacteria experienced different dynamic changes during phytoremediation and a greater abundance of alkB was detected during vegetative growth stages. Because phytoremediation of different components of petroleum is performed by different hydrocarbon-degrading bacteria, plants’ ability of phytoremediating different components might therefore vary during the plant life cycle. Phytoremediation might be most effective during the vegetative growth stages as greater abundances of hydrocarbon-degrading bacteria containing alkB and tol genes were observed at these stages. The information provided by this study enhances our understanding of the effects of petroleum pollution on plant-microbe interactions and the roles of these interactions in the phytoremediation of petroleum-polluted soil

Integrating landscape system and meta-ecosystem frameworks to advance the understanding of ecosystem function in heterogeneous landscapes: An analysis on the carbon fluxes in the Northern Highlands Lake District (NHLD) of Wisconsin and Michigan.

The successful integration of ecosystem ecology with landscape ecology would be conducive to understanding how landscapes function. There have been several attempts at this, with two main approaches: (1) an ecosystem-based approach, such as the meta-ecosystem framework and (2) a landscape-based approach, such as the landscape system framework. These two frameworks are currently disconnected. To integrate these two frameworks, we introduce a protocol, and then demonstrate application of the protocol using a case study. The protocol includes four steps: 1) delineating landscape systems; 2) classifying landscape systems; 3) adjusting landscape systems to meta-ecosystems and 4) integrating landscape system and meta-ecosystem frameworks through meta-ecosystems. The case study is the analyzing of the carbon fluxes in the Northern Highlands Lake District (NHLD) of Wisconsin and Michigan using this protocol. The application of this protocol revealed that one could follow this protocol to construct a meta-ecosystem and analyze it using the integrative framework of landscape system and meta-ecosystem frameworks. That is, one could (1) appropriately describe and analyze the spatial heterogeneity of the meta-ecosystem; (2) understand the emergent properties arising from spatial coupling of local ecosystems in the meta-ecosystem. In conclusion, this protocol is a useful approach for integrating the meta-ecosystem framework and the landscape system framework, which advances the describing and analyzing of the spatial heterogeneity and ecosystem function of interconnected ecosystems

Schematic representation of three types of (three-dimensional) landscape systems represented by a two-dimensional diagram.

<p>Schematic representation of three types of (three-dimensional) landscape systems represented by a two-dimensional diagram.</p

TST, AMI, A, C and R of the C fluxes network in three scenarios (i.e. best estimated, relatively active and relatively inactive) of the Northern Highlands Lake District (NHLD) meta-ecosystem.

<p>TST, AMI, A, C and R of the C fluxes network in three scenarios (i.e. best estimated, relatively active and relatively inactive) of the Northern Highlands Lake District (NHLD) meta-ecosystem.</p

Global constraints and holistic properties of a meta-ecosystem [4, 12, 13].

<p>Global constraints and holistic properties of a meta-ecosystem [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192569#pone.0192569.ref004" target="_blank">4</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192569#pone.0192569.ref012" target="_blank">12</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192569#pone.0192569.ref013" target="_blank">13</a>].</p

Estimated C fluxes into and out of the three major compartments (forests, wetlands and surface waters) of the NHLD [17].

<p>Estimated C fluxes into and out of the three major compartments (forests, wetlands and surface waters) of the NHLD [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192569#pone.0192569.ref017" target="_blank">17</a>].</p

Decision tree of analyzing and classifying landscape systems.

<p>The systemic landscape system embraces all significantly interconnected ecosystems; the fragmental one only embraces a part of significantly interconnected ecosystems; the omnidirectionally discrete one embraces a collection of relatively isolated ecosystems; the laterally discrete one embraces a collection of laterally isolated ecosystems. Small circles represent ecosystems; outer circles represent landscape systems; double-sided arrows represent significant fluxes.</p