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In this paper, one hundred percent of condensed sulfate paper pulp waste liquid was used as the raw material of adhesive, and the activation of its lignin as well as the improving effects of phenol formaldehyde resin and polyfunctional aqueous polymer isocyanate (PAPI) were studied. The results showed that adding formaldehyde to the waste liquid could increase the reactivity of contained lignin, and adding 30% phenol formaldehyde resin or 20% PAPI could make the waste liquid in place of pure phenol formaldehyde resin for producing class I plywood. Furthermore, the cost could be reduced by 55.5% and 49.0%, respectively, in comparing with pure phenol formaldehyde resin. This approach fully used the organic resources in paper pulp waste liquid, reduced environment pollution at the same time, and had unexceptionable economic, social and ecological benefits. The feasibility of preparing adhesives from paper pulp waste liquid was also analyzed by infrared spectrum.

The nitrate removal from groundwater was studied in laboratory columns packed with unprocessed paper as the sole substrate for microbial population. The results showed that the reactor with paper as carbon source started up fast, and temperature and hydraulic retention time (HRT) markedly affected the denitrification process. The denitrification rate at 25 degrees C was approximately 1.7 times higher than that at 14 degrees C. When the initial concentration was 45.2 mg x L(-1), 99.6% of nitrate (nitrite was not detected) could be removed after 8.6 h at 25 +/- 1 degrees C. The nitrogen removal rate was only 50% when HRT was 7.2 h. pH and dissolved oxygen (DO) had little effect on denitrification, and the nitrogen removal rate did not changed when pH value ranged between 6.0-9.0 and DO ranged between 0-6 mg x L(-1). Biofilm was formed on the paper and consumed the paper during the whole process. Using the combined paper reactor and activated carbon adsorption at 25 +/- 1 degrees C and HRT 9.0 h, the nitrate could be completely removed if its initial concentration was not higher than 33.9 mgN x L(-1) and the dissolved organic carbon (DOC) in the effluent was less than 11 mg x L(-1).

Taking'Kyoho' as the test material, the effect of white, green, red and blue bags on volatile compounds in mature grape berries was explored in this study. The results indicated that bags with different colors could create special light conditions, which resulted in the difference of volatile compounds in grape berries. A total of 37, 38, 32, 34 kinds of volatile compounds which included esters, aldehydes, alcohols, ketones, terpenes and aromatic compounds, were detected in 'Kyoho' berries covered with the white, green, red and blue bags respectively, and 33 in the control. Compared with the control, the contents of ethyl acetate, ethyl hexanoate and some other esters decreased, while hexanal, E-2-hexenal and decanal increased in berries with white bags, the contents of the major common compounds, except ethyl 3-hexenoate, ethyl (E)-hex-2-enoate, ethyl 3-hydroxybutyrate, E-2-hexenal, (E,E)-2,4-hexadienal, decanal, and phenethyl alcohol, decreased in berries with green bags, the contents of ethyl acetate, ethyl hexanoate and hexanal, E-2-hexenal decreased in berries with red bags, the contents of ethyl acetate, ethyl hexanoate and some other esters changed slightly in berries with blue bags, except for the increase of hexanal and E-2-hexenal. For those characteristic compounds, the kinds of alcohols in berries covered with bags decreased while the kinds of terpenes and aromatic compounds increased. In general, the fruits with the blue bags had the highest volatile esters, and those with the white bags had high volatile esters and aldehydes, while those with the green and red bags had low aromatic compounds.

To improve the compilation quality of references, work in well with articles search and periodicals evaluation, and promote international academic exchange, the Chinese Journal of Applied Ecology shall adjust its principles of reference recording in scientific papers based on the GB/T7714 -2005. From 2008, the references in scientific papers to be submitted are requested to record by the Citation-Sequence. In this paper, some examples were presented, and the issues needed to be paid more attention to by the authors were put forward.

Mangrove soil is a reliable source for screening cellulose-degrading bacteria due to the high diversity of microbes. To effectively utilize crop straw resources, a cellulolytic bacterium, Paenibacillus silvae strain CH2 was isolated from mangrove soil. We determined the carboxymethyl cellulose (CMC) and filter paper assay (FPA) activities of CH2 at different incubation times, NaCl concentrations, pH and temperatures, estimated the degradation efficiencies of rice and maize straw by CH2, sequenced and analyzed the whole genome of CH2. The results showed that along with the increases of incubation time, NaCl concentration, pH and temperature, the CMC and FPA activities increased first and then decreased . The highest CMC and FPA activities were observed at incubation time of 72-84 h, NaCl concentration of 6.0 g·L -1 , pH of 7 and temperature of 36 ℃. Degradation of straw assays revealed that CH2 could effectively degrade rice and maize straw. At 0 g·L -1 NaCl (the control), the 10-day degradation rates of rice and maize straw were 30.4% and 47.0%, respectively. In the presence of 15 g·L -1 NaCl, the degradation rates were not significantly different from the control, indicating that CH2 had a high tolerance to salts. The whole genome of P. silvae CH2 was 6797325 bp, containing 6312 coding genes. P. silvae CH2 contained multiple genes encoding cellulose and hemicellulose degrading enzymes. These enzymes mainly belonged to the GH family, including endo-1,4-β-xylanase, Xylan 1,4-β-xylosidase, β-glucosidase, and endoglucanase. The results indicated that the bacterium had the potential to be used in crop straw degradation.

High intensity grazing is considered as an important cause of grassland degradation. Numerous studies have explored effects of grazing activities on grassland ecosystems. Nevertheless, the research regarding grazing activity itself, especially the quantification methods and gradient division of grazing pressure, is relatively insufficient. Based on a total of 141 Chinese and English papers containing keywords such as 'grazing pressure', 'grazing intensity', and giving specific quantification methods and classification standards, we sorted out the definition, quantification methods, and grading standards of grazing pressure. The results showed that the definition of grazing pressure in current studies could be classified into two categories: considering the number of livestock carried in the current grassland ecosystem only from the perspective of the amount of grazing livestock; or considering the impacts or consequences on grassland ecosystems. Small-scale manipulative experiments mainly quantified and divided gra-zing pressure by controlling the number of livestock, grazing duration, grazing area, etc . Ecosystem responses to grazing activities were also converted by the above indicators, while the large-scale data spatialization method only considered number of livestock per unit area. The method of remote sensing inversion focused on ecosystem responses, that is, the impacts of grazing activities on grasslands, and it was difficult to separate the role of climatic factors. The quantitative standards of grazing pressure in different grassland types were quite different, even in the same grassland type, and such difference was directly related to grassland productivity.

In order to clarify the influence of livestock grazing managements on C:N:P stoichiometry of grassland ecosystem and improve grassland management ability at global scale, 83 Chinese and English papers were selected for meta-analysis in this study. We explored the effects of grazing herbivore assemblage (sheep alone, cattle alone, and mixed cattle and sheep) and grazing intensity (light grazing, moderate grazing and heavy grazing) on leaf, litter, root and soil C, N and P stoichiometry of grassland ecosystems. The results showed that grazing significantly decreased C content, C/N and C/P, and increased N, P content and N/P in leaf and litter. C content, N content, C/P and N/P were significantly reduced, and P content and C/N were increased in root and soil. Leaf and litter stoichiometry were more sensitive to cattle and sheep grazing alone, while root and soil stoichiometry were more sensitive to mixed grazing. Heavy grazing had a greater impact on the stoichiometry of grassland ecosystems. Grazing reduced soil N content and increased P content, indicating that grazing had different pathways of influence on grassland N and P content. Further research on the mechanisms of N and P content changes in response to unbalanced grazing activities and the incorporation of the effects of grazing herbivore assemblage and intensity into models for predicting and managing grassland ecosystems could effectively improve grassland ecosystem management.

Amorpha fruticosa and Amygdalus pedunculata are common plant species used for greening construction in arid and semi-arid region of Northwest China. In order to explore the feasibility of greening construction and ecological restoration by A. fruticose with A. pedunculata , we exami-ned the allelopathic effects of five concentrations of aqueous leaf extracts of A. fruticosa (0.025, 0.05, 0.10, 0.15 and 0.20 g·mL -1 ) on eight A. pedunculata varieties (YY 1 , YY 3 , YY 4 , YY 5 , YY 6 , SM 6 , SM 7 and SM 8 ), using the methods of paper-petri dish and soilless culture. The results showed that when the concentration of A. fruticosa leaf extracts were 0.025 and 0.05 g·mL -1 , the seed germination and seedling growth of YY 1 and SM 6 were significantly better than other varieties. With increasing concentration of A. fruticosa leaf extracts, the catalase activity of A. pedunculata seedlings first increased and then decreased. The activities of peroxidase and superoxide dismutase, and the contents of soluble protein and chlorophyll showed a downward trend, while the contents of malondialdehyde and soluble sugar and the permeability of cell membrane gradually increased. Results of the principal component and cluster analysis showed that the growth potential of A. pedunculata decreased with the order of YY 1 , SM 6 , SM 8 , SM 7 , YY 6 , YY 3 , YY 5 and YY 4 under the allelopathic effect of A. fruticose . In conclusion, the artificial collocation and mixed planting of low-density of A. fruticosa with YY 1 and SM 6 were beneficial to seed germination and seedling growth of A. pedunculata .

Landscape structure and spatial pattern are the core issues in landscape ecology. The application of graph theory provides a research framework for landscape pattern analysis. Landscape graph based on graph theory is gradually applied to the connectivity modeling of biodiversity conservation and decision support of landscape planning. The representation, analysis and application of landscape graph have become a hot topic in conservation biology and landscape ecology. In this review, we first introduced the graph theory basis of landscape map. Based on the Scopus database, 257 published journal papers with the words "landscape graph", "connectivity" and "network" in titles, abstracts, and keywords from 1993 to 2019 were retrieved. We analyzed the research progress and development trend of this field from the aspects of annual published papers, journal sources, research areas, research institutions and landscape types involved. The results showed that before 2017, the number of journal papers published showed an overall increasing trend, and after 2017, the annual number of published papers decreased year by year. The main research forces were concentrated in United States, France, Canada, and China, contributing to 86.8% of the total published papers. Most of the research results were published in "Landscape Ecology", "Landscape and Urban Planning", and "Biological Conservation". In the research content, the representation of landscape graph mainly included the definition of nodes, the measurement of edges and the simulation of landscape. The analysis of landscape graph involved analysis index and landscape graph partitioning. This study mainly focused on the application of landscape graph in science and practice, including biodiversity conservation, landscape (ecological network) planning and management, the assessment of landscape impacts. Landscape graph based on graph theory influences conservation science and planning practitioners by helping understand landscape connectivity changes, animal behavior and habitat conservation. The impact of graph theory on conservation science and planning comes from the rich theoretical basis and mature research methods. Landscape graph based on graph theory provides a springboard for ecological understanding of landscape structure and pattern, and is an important tool for global researchers and practitioners.

We examined the effects of root extracts of Haloxylon ammodendron and Beta vulgaris in Chenopodiaceae extracted by water and ethanol on seed germination and haustorium formation of Cistanche deserticola by filter paper culture dish method. The results showed that only adding root extract had no effect on seed germination and haustorium formation of C. deserticola . The germination rate of C. deserticola seeds treated by adding 10 mg·kg -1 gibberellin to the root extracted by ethanol was not significantly different from that of the control (GA 3 ), whereas those treated by adding gibberellin to the ethanol extract of two kinds of host root was increased by more than 10 times. The germination rate of C. deserticola seeds in the treatment with adding 1 mg·kg -1 fluridone (FL) to root extract was not significantly different from that in the control with only fluridone, while those in the treatment with B. vulgaris root water extraction was the highest (39.4%). Compared to the treatment of adding gibberellin to the root extract, the germination rate of C. deserticola seeds was only increased. When FL was added to the host root extract, the haustorium was formed on the germination tube, with the formation rate of the ethanol extraction group being the highest (16.2%). Seed germination rate of C. deserticola increased to 52.3% when GA 3 and FL were added to the ethanol extract of H. ammodendron , but the formation rate of haustorium was not different from that of FL treatment. Only 6.7% of the seed formation haustorium in the control was significantly lower than that in FL treatment. There were differences in the position and shape of the haustorium of C. deserticola seeds under different treatments. The haustorium produced by adding the extract of the host root mostly appeared at the top of the bud tube, and many papillae raised into claws. The haustorium of FL treatment without adding the extract of the host root mostly appeared at the bottom or the top of the bud tube splitting. The results indicated that ethanol extraction and water extraction could extract the substances that could promote the formation of C. deserticola seeds haustorium from the host root, but did not affect seed germination. GA 3 and FL could significantly improve the germination rate of C. deserticola seeds, but the formation of the haustorium was affected by some substances in the host root extract.