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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.

Velvetleaf ( Abutilon theophrasti ) is a common weed in dryland, which can reduce crop yield. Allelopathy is one of the possible reasons resulting in crop yield reduction. In this study, we analyzed the allelopathic effect of velvetleaf volatile oil components on germination and seedling growth of three dryland crops, wheat ( Triticum aestivum ), maize ( Zea mays ), and soybean ( Glycine max ). A total of 26 compounds in velvetleaf volatile oil were identified by GC-MS, accounting for 98.1% of the total chromatographic peak areas. The terpenes with lower molecular weight in the volatile oil were α-pinene, eucalyptol, α-terpinolene, β-terpinene, trans-α-ionone, and trans-β-ionone. The saturated aqueous solution of velvetleaf volatile oil could inhibit seed germination of three crops by filter paper and soil. Velvetleaf volatile oil could inhibit the seedling growth of three crops through air, filter paper, and soil. Wheat was the most susceptible to volatile oil, followed by maize and soybean. The inhibitory effect of volatile oil on the growth of wheat was the strongest in air medium, followed by filter paper and soil medium. The lower molecular weight of terpene components from volatile oil might be the important allelochemicals.

Mycorrhizae, formed through the colonization of soil mycorrhizal fungi into the roots of host plants, are common symbiosis in the terrestrial ecosystems. The establishment of mycorrhizae is mainly based on the bidirectional nutrient exchanges between the symbiotic partners. Mycorrhizal fungi can absorb mineral nutrients, such as nitrogen and phosphorus, from soil and transport them to the host plants for their growth. As an exchange, host plants supply mycorrhizal fungi with the carbohydrates in the form of lipids or sugars, which are essential for fungal growth. In recent years, the mechanism of nutrient exchange between the mycorrhizal fungi and host plants has been a hot research topic. Important progresses have been achieved in mechanisms of host plants nutrient uptake and transport mediated by the mycorrhizal fungi. In this review, recent advances in nutrient exchange between arbuscular mycorrhizal fungi, ectomycorrhizal fungi and host plants were summarized, especially in the absorption and bidirectional transfer mechanisms of important nutrients, such as carbon, nitrogen and phosphorus. The potential regulatory effects of nutrient exchange in the mycorrhizal development were also reviewed. In addition, key problems and prospects of related researches were analyzed. This paper would be meaningful for the establishment of mycorrhizal model and the optimization of mycorrhizal effects.

Atmospheric nitrogen deposition has complex effects on individual plants and terrestrial ecosystems. We synthesized results from 39 published papers (16 papers in English and 23 papers in Chinese) and conducted a meta-analysis to evaluate the general responses of tree root traits to nitrogen addition, and further analyzed the difference of N-induced results between English papers and Chinese papers. Our results showed that N addition significantly increased fine root diameter (+6.7%), fine root N content (+8.9%), and root respiration rate (+17.5%), but did not affect fine root biomass, fine root length, specific root length, fine root C content, and fine root C:N ratio. Different climatic zone and fertilizer types had different effects on the experimental results. In addition, experimental results published in English papers were generally more significant than those in Chinese papers. We summarized the general effects of N addition on tree root systems, and further analyzed the mechanisms underlying the effects of N enrichment on forest ecosystem carbon cycle.

The health of wetland ecosphere in an estuarine delta is determined by many factors, such as continuity of natural processes, ecosystem connectivity, habitat heterogeneity, and food web diversity. The contradiction between ecological and environmental protection and regional development in the estuarine delta is becoming more and more prominent. A series of man-made and natural processes directly and indirectly resulted in habitat fragmentation of wetlands, which has direct and strong impacts on the ecosphere health and the habitat function of wetlands. In this paper, we provided a perspective on researches on the basic theory of healthy wetland ecosphere, landscape ecological network system, hydrologic network construction, key food webs, and habitat heterogeneity. At the regional and landscape scales, with the linkages between land use and ecosystem integrity as the main line, we clarified the influences of habitat fragmentation on wetland ecological functions, especially the effects of landscape integrity and river connectivity on wetland habitat. At the community and ecosystem scales, emphasis should be given on the relationship between food web and ecosystem stability, especially the supporting role of food web diversity and habitat heterogeneity on the construction of wetland biosphere. Further efforts should focuse on the wetland habitats construction based on landscape integrity, hydrologic connectivity, habitat heterogeneity and food web diversity. These efforts could help to develop and optimize the theory and method of constructing wetland ecosphere and enhancing its ecological function, and promote the sound development of regional ecological environment and resource utilization in estuarine deltas.

FQA, which uses the conservatism of plant species for particular habitats and the species richness of plant communities, is a rapid method for the assessment of habitat quality. This method is based on species composition of quadrats and coefficients of conservatism for species which assigned by experts. Floristic Quality Index (FQI) that reflects vegetation integrity and degradation of a site can be calculated by a simple formula and be used for space-time comparison of habitat quality. It has been widely used in more than ten countries including the United States and Canada. This paper presented the principle, calculation formulas and application cases of this method, with the aim to provide a simple, repeatable and comparable method to assess habitat quality for ecological managers and researchers.

Soil environmental function regionalization is of significance for soil environmental classification management in China. In this paper, we discussed the broad and narrow concept of soil environmental function and its corresponding attributes. Based on the constraint analysis on the soil environmental quality to function, relationship between soil environmental function and quality was illustrated. Compared with different methods and indices of soil environmental function regionalization, we established the index system of soil environmental function regionalization according to the soil environmental suitability and function. The proposed draft of soil environmental function regionalization included four first-class function types, 10 second-class function types, and 75 soil environmental functional areas. According to the differences among those functional areas, we proposed corresponding management countermeasures. The results provided scientific basis for the control and prevention of soil pollution and the control of regional risk in China.

Ecosystem service flow is the key point and difficulty of ecosystem services research, which is now at the initial stage and show a developing trend of quantity and spatialization. However, the term "ecosystem service flow" is ambiguous. In this paper, we presented two descriptions about the term, and two corresponding theories and methods: the transmission of a service from ecosystems to people and distributed ecosystem model, and the flow of benefits accruing to people as generated by stocks of ecosystem structure and grey/black box theory. Then the latest researches related to the two descriptions were listed, and their merit and demerit were summarized. Finally, we pointed out several directions for future research in ecosystem service flow. Especially, the use of newest space technology and information technology (such as big data) and comprehensive understanding of ecosystem services (such as taking urban ecosystem services flow and abiotic flow into account) should be stressed in the future research.

The paper studied the effects of altitude on reproductive characteristics in 12 populations of Saussurea przewalskii at the eastern Qinhai-Tibetan Plateau, China. The results showed that the size, reproductive organ biomass, vegetative organ biomass, capitulum number, and seed number of individual plant decreased with the increasing altitude, and the capitulum mass and hundred-grain mass increased continuously. S. przewalskii could ensure its reproduction by reducing plant body size to decrease resource consumption, and increasing the allocation of limit resources to flower biomass. In order to ensure sexual reproduction, the reproductive allocation of the plants increased with increasing the altitude. There was a trade-off between capitulum number and capitulum mass, and between seed number and hundred-grain mass, which allowed the plants to maximize their fitness under stressful conditions.

The ecological process models are powerful tools for studying terrestrial ecosystem water and carbon cycle at present. However, there are many parameters for these models, and weather the reasonable values of these parameters were taken, have important impact on the models simulation results. In the past, the sensitivity and the optimization of model parameters were analyzed and discussed in many researches. But the temporal and spatial heterogeneity of the optimal parameters is less concerned. In this paper, the BIOME-BGC model was used as an example. In the evergreen broad-leaved forest, deciduous broad-leaved forest and C3 grassland, the sensitive parameters of the model were selected by constructing the sensitivity judgment index with two experimental sites selected under each vegetation type. The objective function was constructed by using the simulated annealing algorithm combined with the flux data to obtain the monthly optimal values of the sensitive parameters at each site. Then we constructed the temporal heterogeneity judgment index, the spatial heterogeneity judgment index and the temporal and spatial heterogeneity judgment index to quantitatively analyze the temporal and spatial heterogeneity of the optimal values of the model sensitive parameters. The results showed that the sensitivity of BIOME-BGC model parameters was different under different vegetation types, but the selected sensitive parameters were mostly consistent. The optimal values of the sensitive parameters of BIOME-BGC model mostly presented time-space heterogeneity to different degrees which varied with vegetation types. The sensitive parameters related to vegetation physiology and ecology had relatively little temporal and spatial heterogeneity while those related to environment and phenology had generally larger temporal and spatial heterogeneity. In addition, the temporal heterogeneity of the optimal values of the model sensitive parameters showed a significant linear correlation with the spatial heterogeneity under the three vegetation types. According to the temporal and spatial heterogeneity of the optimal values, the parameters of the BIOME-BGC model could be classified in order to adopt different parameter strategies in practical application. The conclusion could help to deeply understand the parameters and the optimal values of the ecological process models, and provide a way or reference for obtaining the reasonable values of parameters in models application.

In recent years, studies on carbon sequestration of biochar in soil has been in spotlight owing to the specific characteristics of biochar such as strong carbon stability and well developed pore structure. However, whether biochar will ultimately increase soil carbon storage or promote soil carbon emissions when applied into the soil? This question remains controversial in current academic circles. Further research is required on priming effect of biochar on mineralization of native soil organic carbon and its mechanisms. Based on the analysis of biochar characteristics, such as its carbon composition and stability, pore structure and surface morphology, research progress on the priming effect of biochar on the decomposition of native soil organic carbon was reviewed in this paper. Furthermore, possible mechanisms of both positive and negative priming effect, that is promoting and suppressing the mineralization, were put forward. Positive priming effect is mainly due to the promotion of soil microbial activity caused by biochar, the preferential mineralization of easily decomposed components in biochar, and the co-metabolism of soil microbes. While negative priming effect is mainly based on the encapsulation and adsorption protection of soil organic matter due to the internal pore structure and the external surface of biochar. Other potential reasons for negative priming effect can be the stabilization resulted from the formation of organic-inorganic complex promoted by biochar in the soil, and the inhibition of activity of soil microbes and its enzymes by biochar. Finally, future research directions were proposed in order to provide theoretical basis for the application of biochar in soil carbon sequestration.