The plasticity response of Quercus variabilis and Quercus mongolica seedlings to combined nitrogen (N) deposition and drought stress was evaluated, and their performance in natural niche overlaps was predicted. Seedlings in a greenhouse were exposed to four N deposition levels (0, 4, 8, and 20 g N m−2 year−1) and two water levels (80 and 50 % field-water capacity). Plant traits associated with growth, biomass production, leaf physiology, and morphology were determined. Results showed that drought stress inhibited seedling performance, altered leaf morphology, and decreased fluorescence parameters in both species. By contrast increased N supply had beneficial effects on the nutritional status and activity of the PSII complex. The two species showed similar responses to drought stress. Contrary to the effects in Q. mongolica, N deposition promoted leaf N concentration, PSII activity, leaf chlorophyll contents, and final growth of Q. variabilis under well-watered conditions. Thus, Q. variabilis was more sensitive to N deposition than Q. mongolica. However, excessive N supply (20 g N m−2 year−1) did not exert any positive effects on the two species. Among the observed plasticity of the plant traits, plant growth was the most plastic, and leaf morphology was the least plastic. Therefore, drought stress played a primary role at the whole-plant level, but N supply significantly alleviated the adverse effects of drought stress on plant physiology. A critical N deposition load around 20 g N m−2 year−1 may exist for oak seedlings, which may more adversely affect Q. variabilis than Q. mongolica.

Increasing atmospheric nitrogen (N) deposition and biological invasion have become major concerns with global environmental change. This study aimed to determine the effects of an exotic species on a native one under increasing N deposition.We conducted a greenhouse experiment in which the exotic species Robinia pseudoacacia and the native species Quercus acutissima were grown in mixture and monocultures under four levels of simulated N deposition (0, 3, 6, 12 g m−2 year−1). After 12 weeks of treatment, plant growth, leaf physiological traits and soil chemical properties were determined.With its strong capability for nutrient absorption and carbon assimilation, R. pseudoacacia dominated in competition. R. pseudoacacia reduced the growth of Q. acutissima, but the relative competition index decreased with increasing N deposition. At the end of the experiment, the soil available phosphorus (P) in mixture was significantly lower than that in the monoculture of Q. acutissima, while the soil available N in the two cultivations did not show obvious differences.Increased N deposition alleviated the competitive effects of R. pseudoacacia on Q. acutissima. In the future, besides N, increased P availability should also be considered in the interaction between the two species.

Acer buergerianum Miq. (Trident maple) is a native species of China with a large distribution, but exist in small population. Water and light are two important factors limiting plant growth and are crucial in the framework of forest regeneration. However, there is no consensus on how shade interacts with drought. Four hypotheses in the recent literature variously predict that shade will have a stronger, weaker or equal impact on seedlings under drought stress. This study investigated the interactive responses of A. buergerianum to light and water focusing on seedling growth, leaf morphology and biomass partitioning by performing a growth experiment in pots with different water supply regimes [15, 35, 55, 75, 95 % of field capacity (FC)] combined with two light regimes (10 and 66 % of full sunlight). After 123 days treatment, the results showed that shade greatly reduced growth and biomass, in contrast enhancing the amount of chlorophyll, the amount of water in the leaves, and the specific leaf area. Drought reduced growth, biomass, and the bulk of the leaves. Most leaf traits and biomass characteristics had strong interactions in their responses to light and water treatments. Allometric analysis revealed that water and light had no effects on root to shoot ratios, main root to lateral root ratios, and root mass ratios. Shade alleviated the negative impact of drought. A. buergerianum successfully adapted to the various light and water conditions. We recommend a water supply above 15 % FC to keep the seedlings vigorous, under both sunlight conditions.

Constructed wetland has been widely adopted to deal with degraded natural wetlands and water bodies; thus, more attention should be focused on ecological–economic sustainability and ecological efficiency of these projects for long-term success. Emergy accounting was conducted to investigate the energy and resource flows in constructed wetlands during the restoration process. Emergy-based indexes were adopted to evaluate the sustainability of a pilot large-scale constructed wetland in a large wetland restoration project in North China, carried out to enhance the river water quality and offset the degradation of natural wetland. Emergy and emdollar values for ecosystem services and natural capital were also calculated. The results showed that when outflow was considered as the product, the studied large-scale constructed wetland was more self-supporting and could be operated with lesser financial investment, although the waste treatment efficiency and the sustainability index were lower than conventional small-scale treatment constructed wetlands. Compared with natural wetlands, more visits from tourists and lesser financial investment coming in as feedback into the wetland would reduce system environment loading and promote system self-support ability, ultimately generating sustainability. In addition, the studied large-scale constructed wetland can effectively simulate energy and resource flows of natural wetland ecosystem and contribute a roughly equal value of ecosystem services in term of gross primary production. The studied large-scale constructed wetland can successfully achieve ecosystem functions as replacement for natural wetland and hasten the restoration process, although the restoration effectiveness of ecosystem structures in terms of living biomass and water using emergy-value accounting is still inconclusive.

Urbanization is one of the most important anthropogenic activities that create extensive environmental implications at both local and global scales. Dynamic urban expansion models are useful tools to understand the urbanization process, project its spatiotemporal dynamics and provide useful information for assessing the environmental implications of urbanization. A hybrid urban expansion model (NNSCA model) was proposed to simulate rapid urban growth in a typical industrial city, Dongying, China, by coupling a artificial-neural-network-based stochastic cellular automata model and several socioeconomic indictors, i.e., the per capita income of the rural population, the per capita income of the urban population, population and gross domestic products of the city. Good conformity between simulated and actual urban patterns suggested that the NNSCA model was able to effectively simulate historic urban growth and to generate realistic urban patterns. A series of scenario analyses suggested that the expanding urban would threaten the ecosystem health of coastal wetlands in the city unless environmental protection actions are taken in the future. The NNSCA model provides abilities to assess future urban growth under various planning and management scenarios, and can be integrated into ecological or environmental process models to evaluate urbanization’s environmental implications.

Water is a main factor limiting plant growth. Integrative responses of leaf traits and whole plant growth to drought will provide implications to vegetation restoration. This study investigated the drought responses of Vitex negundo L. var. heterophylla (Franch.) Rehd. with a focus on leaf morphology and physiology, seedling growth and biomass partitioning. Potted 1-year-old seedlings were subjected to four water supply regimes [75, 55, 35 and 15% field capacity (FC)], served as control, mild water stress, moderate water stress and severe water stress. Leaf morphological traits varied to reduce the distance of water transfer under water stress and leaflets were dispersed with drought. Net photosynthetic rate decreased significantly under water stress: stomatal closure was the dominant limitation at mild and moderate drought, while metabolic impairment was dominant at severe drought. The physiological impairment at severe drought could also be detected from the relative lower water use efficiency and non-photochemical quenching to moderate water stress. Total biomass of well-watered plants was more than twice that at moderate water deficit and nearly ten times that at severe water deficit. In summary, V. negundo var. heterophylla had adaptation mechanism to water deficit even in the most serious condition, but different strategies were adopted. Seedlings invested more photosynthate to roots at mild and moderate drought while more photosynthate to leaves at severe drought. A nearly stagnant seedling growth and a sharp decline of total biomass were the survival strategy at severe water stress, which was not favorable to vegetation restoration. Water supply above 15% FC is recommended for the seedlings to vegetation restoration.

Leaf morphological, physiological and biochemical characteristics of Robinia pseudoacacia L. seedlings were studied under different stress conditions. The plants were subjected to drought and shade stress for one month. Leaf inclination, chlorophyll fluorescence and chlorophyll content were measured at the first day (short-term stress) and at the end of the stress period (long-term stress) and in the recovery period. Leaf inclination was affected mainly by light; a low level of irradiance caused leaves to be arranged horizontally. Diurnal rhythmicity was lost after the long-term stress, but resumed, in part, in the recovery period. Drought stress caused leaves to tilt more obviously and decreased damage to the photosystem. Sun avoiding movement in a single leaf and sun tracking movement in the whole plant coexisted. Significant physiological changes occurred under different conditions of light. Increased energy dissipation and light capture were the main responses to high and low level of irradiance, respectively, and these were reflected by changes of chlorophyll fluorescence and chlorophyll content. Phenotypic plasticity in the leaflet enhanced the protective response to stress. These adaptive mechanisms may explain better survival of R. pseudoacacia seedlings in the understory, especially during the drought periods, and made it to be the preponderant reforestation species in Shandong Province of China.

In China urban development policies (UDP) are legislated aiming to promote the cities’ socio-economic development. Urbanization, however, leads to urban expansion and land-use changes, which in turn affects the structure, function and processes of terrestrial and marine ecosystems. Rizhao City, a seaport city of China, was chosen as a case study in order to study the ecological impacts of UDP at a strategic level. Ecosystems and their components were identified and assessed. The changes of biodiversity, habitats and ecosystem services caused by the UDP of Rizhao City were examined and analyzed. We found that UDP contributes in an essential way to protect and maintain the ecosystems and their components when it comes to land-use change. Based on our analysis, ecosystems as well as ecosystem services of Rizhao City are expected to be maintained in the near future with the current UDP.

Leaves are organs sensitive to environmental changes in the process of evolution and may exhibit phenotypic plasticity as a response to abiotic stress. However, affirmation of leaf morphological plasticity and its regulations in different environments are still unclear. We performed a simulated experiment to study the variations of leaf morphology in different gradients of water and light availability. Considering different types of leaves and venation, we chose pinnate-veined simple leaves of Quercus acutissima and compound leaves of Robinia pseudoacacia as the study objects. The morphological parameters we investigated include leaf size, shape and venation pattern which can be easily measured in the field. Significant variations occurred in many parameters due to the effects of the environment and/or allometry. There were broadly consistent trends for leaf morphological variations along the gradients. The leaf size became smaller with a short supply of resources. Leaf elongation and fractions of the lamina area altered to enhance resources acquisition and conservation. Trade-offs between investments in support and functional structures optimized the venation pattern of major and minor veins. Leaflets partially played a role such as leaf teeth, for they are not only individual units, but also a part of the compound leaf. We suggest that more or less the same trends in morphological variations may be an important explanation for coexisting species to adapt to similar habitats and form the niche differentiation.

A series of batch equilibration experiments were conducted to assess the adsorption and desorption of divalent mercury (Hg2+) by humic acids (HAs) and fulvic acids (FAs) extracted from black soil and red soil in China. The Fourier transform infrared (FTIR) spectroscopy, cross-polarization (CP) with magic-angle spinning (MAS) 13C nuclear magnetic resonance (NMR) spectroscopy and scanning electron microscopy (SEM) were jointly adopted to characterize the humic substances (HSs) samples and HSs–Hg complexes. The FTIR spectra showed that the adsorption of Hg2+ mainly acted on O–H, C–O and CO groups of HAs and FAs. The NMR spectra indicated that HAs are higher in Paraffin and carbonyl C content compared with corresponding FAs, while FAs exhibit higher methoxy C, O-alkyl C and carboxyl C contents. The SEM images revealed the different surface structures of HAs, FAs and HSs–Hg complexes, which explains Hg2+ complexation phenomenon on HSs. The study also showed that HAs have higher adsorption capacity for Hg2+ than those of FAs. Hg2+ adsorption isotherms could be well fitted with both Langmuir and Freundlich equations. The desorbed percentages of all HSs samples were less than 1%, which indicated their high binding strength for Hg2+. Furthermore, HAs samples have a lower desorption ratio than FAs, HAs can play a more important role in pollution control of Hg2+ in environment.

This study surveyed and analyzed the vegetation heterogeneity in the Center of Inner Mongolia (CIM) by a new method based on the beta-binomial distribution for each kind of vegetation. As many as 190 large quadrats of 5 mm × 5 mm (representing an area of 50 km × 50 km) (referred to as L-quadrats hereafter) were extracted from about an area of 475,000 km2. Each L-quadrat was divided into four small quadrats (S-quadrat) of 2.5 mm × 2.5 mm (equivalent to 25 km × 25 km) and the frequency of occurrence of each type of vegetation was recorded in each small quadrate. The weighted average heterogeneity from all of the vegetations composing a landscape provides a measure at landscape level to determine the spatial intricateness of landscape composition. Our results indicated that each vegetation has its own distribution pattern and the degree of heterogeneity is different from one kind of vegetation to the other. The results proved that the beta-binomial distribution can be very useful for analyzing vegetation landscapes.

This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and database technology to the research of alien species. The modules of alien species database, including classified data input, statistics and analysis, species pictures and distribution maps, and out date input, were approached by Visual Studio.net 2003 and Microsoft SQL server 2000. The alien species information contains the information of classification, species distinction characteristics, biological characteristics, original area, distribution area, the entering fashion and route, invasion time, invasion reason, interaction with the endemic species, growth state, danger state and spatial information, i.e. distribution map. Based on the above bases, several models including application, checking, modifying, printing, adding and returning models were developed. Furthermore, through the establishment of index tables and index maps, we can also spatially query the data like picture, text and GIS map data. This research established the technological platform of sharing information about scientific resource of alien species in Shandong Province, offering the basis for the dynamic inquiry of alien species, the warning technology of prevention and the fast reaction system. The database application system possessed the principles of good practicability, friendly user interface and convenient usage. It can supply full and accurate information inquiry services of alien species for the users and provide functions of dynamically managing the database for the administrator.

Strategic Environmental Assessment (SEA), a newly-developed decision-making support tool, has been used in many developed and developing countries for predicting and evaluating potential environmental impact of policies, plans, and programs (PPPs), as well as for providing alternatives to avoid, mitigate, or compensate for these impacts. Unfortunately, due to the complexity and flexibility of SEA, to date there has been no consensus on a system which could be suitable for the contexts of different regions or countries. Different requirements and practices are observed in the different typical stages of SEA. Controversial areas include the appropriate indicators to apply in the early baseline setting stage, suitable methodologies for the impact assessment, and appropriate procedures for the SEA process. Given this, it is important to review and refine the SEA system specific to the context but informed by internationally agreed norms. As an illustration, this study reviews and proposes steps to refine the SEA system in Shandong Province, an economically powerful province of China, aiming to achieve sustainable development. Supported by the Environmental Impact Assessment Law of the People's Republic of China, Shandong Province employed SEA to reform the traditionally economy-oriented decision-making and incorporate consideration of environmental consequences into government deliberation on proposed PPPs. This paper illustrates the developmental process, procedures, and legal support for SEA in Shandong Province. By analyzing five SEA cases carried out by Shandong Province Environment Protection Bureau (SEPB) and Shandong University, problems in the SEA system were identified, and recommendations were made for improving the SEA system not only in Shandong Province but also other similar regions or countries.

Petroleum-contamination soil is ubiquitous. The various sources of this contamination necessitate the effective evaluation of the contamination level, contaminant transport analysis and identification of the pollution sources. In the present study, soil profiles were collected from both upland and paddy fields along the strike of the irrigation canals in the Hunpu wastewater irrigation region in northeast China. The concentrations of aliphatic hydrocarbons in the soil were analyzed. The sites near the oil wells, wastewater irrigation canal and Shenyang City were found to have high concentrations of [∑ n-alkanes (sum of n-alkanes): (0.8 to 32.2) μg g− 1 dry wt.; TAH (total aliphatic hydrocarbons): (5.0 to 161.2) μg g− 1 dry wt.]. The geochemical analysis results showed various degrees of petroleum pollution. The ∑ n-alkanes varied (0.5 to 7.5) μg g− 1 while TAH varied (1.6 to 47.2) μg g− 1 at other sites where biogenic hydrocarbons were dominant. The results from the principal components and redundancy analyses showed that the samples containing hydrocarbons from wastewater irrigation, oil wells, and atmospheric deposition were partitioned into different groups. These results further represented that the soil properties had some effects on hydrocarbon distribution especially the sand content which had significantly negative correlation with oil-related hydrocarbons. The current study showed that the early input and vertical migration of hydrocarbons resulted in a high deep-soil hydrocarbon concentration.Highlights► We found the hydrocarbon concentration in soil near pollution sources was high. ► Sewage was considered to promote the downward migration of organic pollutants. ► Different petrogenic and biogenic sources were showed by geochemical analysis. ► The samples affected by various sources were partitioned by CANOCO. ► The redundancy analysis results showed the effects of the soil properties.

There has been much debate on the topic of whether stricter environmental regulations can promote environmental performance and economic performance at the same time. Different researchers have used different indicators to measure environmental performance and economic performance in their empirical studies. However, it is a surprise that few studies have checked the relationship between environmental regulation and eco-efficiency, as the latter is widely regarded as a quite powerful tool of considering ecology and economy together.In this study the background is the implementation in 2003 of the Stricter Discharge Standard (SDS) in Shandong Province’s Pulp and Paper Industry (SPPI), compared to the national standards of China. The stricter regulations were intended to promote corporate change from passive management to active control and from end-of-pipe treatment to cleaner production. This study investigated the eco-efficiency trends of SPPI from 2001 to 2008 in three fields: water efficiency, energy efficiency and environment efficiency. A “de-linking” and “re-linking” tool was used to attain a further evaluation. The study showed that with the implementation of stricter regulation most of the efficiency indicators (except CO2 emission and energy consumption) had achieved significant improvements, and the overall environmental performance trends of SPPI showed it to be more sustainable. However, the study also found that it was not enough to address a single indicator in the environmental regulation of the pulp and paper industry. More holistic eco-efficiency indicators need to be further considered and introduced to the industry as the next step to create true sustainable development.

To evaluate petroleum contamination of groundwater and air and identify its sources in the Hunpu, a wastewater-irrigated area located in the southwest of Shenyang, concentrations of aliphatic hydrocarbon components were analyzed by gas chromatography. The analysis revealed the presence of biogenic and degraded petrogenic hydrocarbons. For water, petroleum pollution and degradation levels were significantly higher in October 2009 [total aliphatic hydrocarbons (TAH): 909.3–10343.1 μg L− 1] than those in May of the same year (TAH: 357.0 to 6802.1 μg L− 1). For air, the concentrations of ∑ n-alkanes, unresolved complex mixture (UCM), and TAH were lowest in winter (∑ n-alkanes: 76.6 μg m− 2 d− 1, UCM: 147.9 μg m− 2 d− 1, and TAH: 224.5 μg m− 2 d− 1); the n-alkanes were more abundant in spring (841.2 μg m− 2 d− 1); and UCM and TAH were more abundant in summer and autumn (UCM: 13173.7 μg m− 2 d− 1 and TAH: 13859.9 μg m− 2 d− 1). Through principal component analysis, the water and air sampled in different seasons and sites were differentiated based on their degree of petroleum pollution and various aliphatic hydrocarbon compositions. Through redundancy analysis, we found the effect of irrigation water on the surface soil was much higher than that of atmospheric deposition. The variance of hydrocarbon composition in soil, explained by the hydrocarbon composition in water collected in the main irrigation period, May 2009, was 70.5%, whereas the value for atmospheric deposition was only 12.2%.Highlights► Biogenic and various petrogenic hydrocarbons were identified in water and air. ► Pollution and degradation of water were heavier in October than those in May. ► For air, pollution was lightest in winter and heaviest during summer and autumn. ► Various hydrocarbon concentrations and compositions were identified by PCA. ► We found the effect of irrigation water on soil was higher than that of air by RDA.

The soil microorganisms at different depths play an important role in soil formation, ecosystem biogeochemistry, recycling of nutrients, and degradation of waste products. The aims of this study were to observe the microbial diversity in the profile of an agricultural soil in northern China, and to research the correlation between soil microbes and geochemistry. First, the soil geochemistry of the profile was investigated through 25 chemical elements. Secondly, the various physiological groups of microorganisms were studied by traditional culture methods. Thirdly, the functional diversity on sole carbon source utilization (SCSU) was evaluated by the BIOLOG system. Finally, the correlation between the soil microbial diversity and geochemistry was analyzed statistically. The results showed that the amounts and proportions of various physiological groups of microorganisms changed with depth. The bacterial functional diversity on SCSU decreased with increasing depth, but evenness of the substrate utilization increased. Although the microbial metabolic diversity was different at every depth, it could be classified into three main groups by principal component analysis and cluster analysis. The various physiological groups of microorganisms showed remarkable correlation with relevant soil chemical elements. The sensitive microbial indicators of soil health were expected to be screened out from actinomyces or ammonifying bacteria.

This study surveyed and analyzed the vegetation heterogeneity in the Center of Inner Mongolia (CIM) by a new method based on the beta-binomial distribution for each kind of vegetation. As many as 190 large quadrats of 5 mm × 5 mm (representing an area of 50 km × 50 km) (referred to as L-quadrats hereafter) were extracted from about an area of 475,000 km2. Each L-quadrat was divided into four small quadrats (S-quadrat) of 2.5 mm × 2.5 mm (equivalent to 25 km × 25 km) and the frequency of occurrence of each type of vegetation was recorded in each small quadrate. The weighted average heterogeneity from all of the vegetations composing a landscape provides a measure at landscape level to determine the spatial intricateness of landscape composition. Our results indicated that each vegetation has its own distribution pattern and the degree of heterogeneity is different from one kind of vegetation to the other. The results proved that the beta-binomial distribution can be very useful for analyzing vegetation landscapes.