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Tang T.,CAS Wuhan Institute of Hydrobiology | Jia X.,CAS Wuhan Institute of Hydrobiology | Jia X.,China Academy of Forestry | Jiang W.,CAS Wuhan Institute of Hydrobiology | And 2 more authors.
Hydrobiologia | Year: 2015

Research on multi-scale temporal dynamics of lotic algal assemblages remains scarce. In this study, we analyzed epilithic algae sampled monthly from a Chinese subtropical mountain river network from 2004 to 2007, by using a multivariate time series modeling approach. We hypothesized that (1) multi-scale temporal dynamics exist within algal communities; (2) physical and chemical conditions drive algal temporal dynamics; and (3) tributary sites differ in algal temporal changes. This study revealed 2–4 site-specific algal temporal dynamics, contributed by 23–45% component taxa. Among the time-related taxa, percentages of high profile guild taxa were higher than both the low profile and the motile guild taxa. Several algal temporal dynamics were found to be driven by water temperature, conductivity, or current velocity, within which influences of conductivity at two sites resulted in directional changes in algal communities. Furthermore, tributary sites differed in algal temporal changes when compared to the two mainstream sites. Our findings imply that natural fluctuations and agricultural disturbance together shaped algal temporal dynamics in the studied river network. In conclusion, for accurately tracking algal temporal dynamics, we recommend that long-term and high-frequency biomonitoring protocols are developed. Moreover, both the mainstream and tributary sites should be monitored simultaneously. © 2015 Springer International Publishing Switzerland Source

Yang H.,Nanjing Agricultural University | Xu J.,Nanjing Agricultural University | Guo Y.,Nanjing Agricultural University | Koide R.T.,Brigham Young University | And 5 more authors.
Fungal Ecology | Year: 2016

The arbuscular mycorrhiza (AM) is among the most ubiquitous symbiosis in the world. A meta-analysis of 759 articles (1978-2012) was conducted to test whether ecologically important host plant traits (N-fixation and C-fixation pathway) affect the response of the plant to mycorrhizal colonization. We found that the effect of N-fixation on mycorrhizal growth response (MGR) depended on whether the plant was woody or a forb. N-fixing forbs had a higher MGR than non-N-fixing forbs, but the reverse was true for woody plants. Moreover, C4-grasses had significantly higher MGR than C3-grasses, but no significant difference was found between C3 and C4 forbs, or between C3 and C4 woody species. Overall, woody species had higher MGR than any other functional group. These results demonstrate that MGR does depend on host functional characteristics, but neither N-fixation capacity nor C-fixation pathway are apparently fundamental controllers of MGR. Instead, it would appear possible that these traits influence MGR only insofar as they influence more fundamental functions such as P demand and P supply. © 2015 Elsevier Ltd and The British Mycological Society. Source

Liu S.-Z.,Central South University of forestry and Technology | He X.-D.,Central South University of forestry and Technology | Li J.-J.,Central South University of forestry and Technology | Li J.-J.,China Academy of Forestry
Chinese Journal of Ecology | Year: 2014

According to the theory of system science, this paper established an evaluation system of forest health including 13 indicators from system vitality, composition and resilience and forest environment aspects. To solve the problem in which the health evaluation values are unknown, that is, no decision attribute, this paper applied attribute importance degree of rough set theory to analyze the indexes' influence on forest health, with the forest health evaluation index weight being obtained based on knowledge granularity and attribute importance. We took eight secondary forest communities and two plantations in Daweishan Nature Reserve of Hunan Province as study cases. The results showed that the weights of 13 indexes were basically consistent with the expert scoring results. The evaluation results indicated that only one plot was at health level, seven at sub-health level and two at unhealthy level. Compared with the analytic hierarchy process method (AHP) and the principal component analysis method (PCA), this method did not need any prior information but took the information related to the forest health system as the basis to mine correlation and importance degree among factors directly reflecting forest health. It did not depend on experts' experience, and the greater the amount of information, the more objective the attribute weight was. The results suggested that the evaluation method was real and effective and the evaluation result was more objective, providing a theoretical basis for forest health assessment and management. Source

Zhou C.-X.,Huazhong Agricultural University | Min S.-F.,Hubei Ecology Vocational College | Yan-Long T.,China Academy of Forestry | Wang M.-Q.,Huazhong Agricultural University
Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics | Year: 2015

We constructed an antennal transcriptome of the parasitoid wasp, Sclerodermus sp. (Hymenoptera: Bethylidae). Our analysis of the transcriptome yielded 51,830,552 clean reads. A total of 46,269 unigenes were assembled, among which 29,582 unigenes exhibited significant similarity (E-values ≤ 10;bsup&- 5;esup&) to sequences in the NCBI nonredundant protein database. Gene ontology (GO) and cluster of orthologous groups (COG) analyses were used for the functional classification of these unigenes. We identified ten odorant binding proteins (OBPs), ten chemosensory proteins (CSPs), eight olfactory receptors (ORs), three ionotropic receptors (IRs), six gustatory receptors (GRs), and two sensory neuron membrane proteins (SNMPs). The expression profiles of the ten OBPs were determined based on a qPCR analysis of RNA extracted from the antennae, legs, and abdomens of wingless and winged female adults and whole larvae and pupae. The highest levels of OBP5, OBP6, OBP7, and OBP9 expression were observed in the antennae of adult females. The highest levels of OBP1, OBP2, and OBP4 expression were observed in the abdomen of winged females. The highest levels of OBP3 and OBP10 expression were observed in larvae and pupae, respectively, whereas OBP8 was expressed at high levels in both larvae and pupae. Our findings establish a foundation for future studies of the molecular mechanisms of chemosensory perception in Sclerodermus sp. © 2015 Elsevier Inc. All rights reserved. Source

Kong S.-X.,China Agricultural University | Kong S.-X.,Shining herb Beijing International Bio Technology Co. | Li H.-K.,China Academy of Forestry | Wang B.-M.,China Agricultural University | And 3 more authors.
Chinese Traditional and Herbal Drugs | Year: 2015

Objective: To study the effect of different concentration of plumbum (Pb) stress on antioxidase activity in different organs of Rabdosia Rubescentis Folium (RRF, the aerial parts of Rabdosia rubescens) and their growth, and provide the basis for the growth regulation of R. rubescens under Pb pollution. Methods: Ramets hydroponic test was performed with the concentration of Pb (0, 135, 270, and 540 mg/L) and the stress time (50 d), taking superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), relative growth rate (RGR), biomass, and Pb mass fraction as indexes, the determination of antioxidant enzyme activity was performed with spectrophotometer, and plant's Pb mass fraction of plant with plasma emission spectrometer was carried out. Results: Under Pb stress at different concentration (135-540 mg/L), SOD activity in the leaves and the roots of R. rubescens was increased first and then decreased, but no significant difference on SOD activity in the leaves at each level; POD activity in the leaves under Pb concentration (135-270 mg/L) was no significant difference compared with the control group, but was significantly increased at the concentration of 540 mg/L, while the POD activity in the roots under Pb stress at various concentration was significantly lower than that of the control group which gradually went up after declined; CAT activity in the leaves increased significantly with Pb concentration rising, and the activity in the root decreased gradually with Pb concentration rising. No significant effect on the growth of R. rubescens at low and mid levels of Pb concentration (135 and 270 mg/L), but under high concentration (540 mg/L) of Pb treatment compared with the control group, the biomass and RGR decreased by 33.33% and 46.59%, respectively. Conclusion: The stimulus response is different obviously for antioxidase activities between the leaves and roots of R. rubescens; Through fitting model predictive analysis, the critical Pb concentration is 301.99 mg/L, which decreases RGR by 10% compared with control group (P < 0.01). RRF shows a strong resistance to Pb stress. © 2015, Editorial Office of Chinese Traditional and Herbal Drugs. All right reserved. Source

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