By high-throughput sequencing on Illumina Miseq platform and bioinformatics, changes of soil bacterial communities in a small- to medium-diameter Phyllostachys edulis plantation subjected to different soil management practices (mulching, alternate operation, and long-term mulching) were analyzed to investigate the mechanism of soil bacterial community variation and its effect on soil degradation of mulched P. edulis plantation. The results showed that soil subjected to four different soil management practices (CK, mulching, alternate operation, and long- term mulching) contained a wide diversity of bacterial communities covering 26 phyla, 69 classes, 118 orders, and 197 genera. Among them, Acidobacteria were the dominant in all four plots (30.85%- 44.22%), followed by Proteobacteria (8.23%-25.41%), Chlorobacteria (2.48%-7.91%), Verrucomicrobia (2.39%-6.82%), AD3 (1.05%-15.18%), Actinobacteria (3.99%-8.39%) and TM7 (0.61%-6.68%). Soil total nitrogen and total organic carbon of all the three treatment sample plots were higher than those of the CK. The soil pH of the sample plots of mulching, alternate operation, and long-term mulching significantly decreased, and the soil became more acidic as the mulching period was prolonged. α-diversity and principal co-ordinate analysis showed that mulching had a greater impact on the diversity and structure of the soil bacterial community, and increased the number, species and abundance of bacteria. The shallow tillage of soil surface under the mulching prevented mechanical disturbance of the soil, thus forming a 0-20 cm thick layer of semi-decomposed organic matters within a short period of time to provide energy sources for bacterial reproduction. The alternate operation plot showed the greatest number, species and abundance of bacteria. However, the long-term mulching plot showed a decrease in the number, species and abundance of bacteria, as well as a significantly lower Chao1 index than the CK. This study provides technical support and data reference for research on orientation cultivation of low-yield bamboo and ecological restoration technology of bamboo forest.

Based on the hydrologic data of East Tiaoxi watershed from 2011 to 2014, taken ammonia nitrogen as control criterion, we calculated the ammonia assimilative capacity of four areas divided from upstream to downstream by load duration curve, and analyzed spatial and temporal variation of assimilative capacity in the basin. Combined with the actual water quality data, we measured the residual assimilative amount. The results showed that the assimilative capacity fluctuated dramatically with time, and the high assimilative capacity was mainly from June to September and March. The summer had the maximal assimilative capacity while the winter had the minimal one. The assimilative capacity of wet season was 1.7 times and 2.4 times that of the normal season and the dry season, respectively. Moreover, the assimilative capacity in downstream area was higher than that in upstream area, especially in dry condition interval when the assimilative capacity in downstream was 4.8 times of that in upstream. Except Luoshezha station, the residual assimilative capacity of other stations had the same variation, which showed as high flow interval＞moist condition interval＞mid- range flow interval＞dry condition interval＞low flow interval. The residual assimilative capacity in the Luoshezha station was low in the high flow interval and moist condition interval because of non- point source pollution. In conclusion, the load duration curve is effective in calculating and analyzing assimilative capacity, and this study provides valuable principles for total capacity control in watershed scale.

In order to provide scientific supports for watershed sustainable development, operation and management, Nanxi River was selected as a typical red-soil region, and ecosystem health assessment methodology and pressure analysis combining remote sensing (RS), geographic information system (GIS) and multi-index were applied. The ecosystem health assessment was classified into two categories: water area and terrestrial area, and the indices were divided into six sections including habitat structure, aquatic organisms, ecological pressure of water area and ecological patterns, ecological function, ecological pressure of terrestrial area, which consisted of 16 sub-indicators. The results showed that the health condition of the study area was good, and only the aquatic organisms and ecological function were in ordinary condition. Among them, 83.3% of sub-basins were in good condition, while the others were in ordinary condition, and all of them were located in the downstream areas. Human disturbance was the major reason of the degradation of watershed ecosystem health, such as rapid growth of urban land areas, excessive livestock breeding and fishing. In order to improve the health conditions, more attention should be paid to adjusting the scope of the conservation areas, controlling pollution from point and nonpoint sources as well as protecting the biodiversity. The proposed assessment methodology can comprehensively indicate the health condition of Nanxi River. This case study could make a contribution to guiding the watershed management in ecologically fragile areas, and ensuring the water ecological health of the basin and its downriver.

Soil and water assessment tool (SWAT) was employed to analyze the main sources and patterns of eutrophic pollutants in Laohutan reservoir, located in Huzhou City, Zhejiang Province from Jan. 2010 to Apr. 2015. The situation of hydrology, water quality and economic benefit in the reservoir area under six management measures was simulated with scenario analysis. The results showed that the accuracy of daily runoff simulation was pretty good, with the percent bias (BIAS) below 20% (－17.57%-－0.63%), coefficient of determination (R²) greater than 0.75 (0.79-0.85), Nash-Sutcliffe coefficient of efficiency (NSCE) greater than 0.70 (0.71-0.86). The simulation of total nitrogen was relatively good (NSCE=0.39-0.58, R²=0.58-0.74, BIAS=－14.08%-7.18%), which met the requirements of the model. Therefore, the simulation results can reflect the hydrology and water quality changing rule of Laohutan reservoir. Compared to various hypothetical scenarios, the best water quality safety management measure was found to be promoting scientific fertilization. In conclusion, the SWAT model is applicable to simulate the runoff and agricultural nonpoint-source pollution in hilly area of western Zhejiang, and it is of scientific significance for hydrological simulation and nonpointsource pollution control in this area.

Based on the concentrations of SO_², NO_², CO, O_³, PM_^2.5 and PM_¹⁰ measured by Xixi monitoring station, meteorological data such as temperature, relative humidity, wind speed, visibility and rainfall, variation characteristics and correlations of various air pollutants in Hangzhou City from December 2014 to November 2016 were analyzed, and the influence of meteorological conditions on pollutants was discussed. The results showed that the concentrations of SO_² and CO reached the first grade standard of air quality during the study period. NO_² and particulate matter were severely over-standard and the average concentrations of NO_², PM_^2.5 and PM_¹⁰ were 1.21, 1.40 and 1.04 times of the second grade standards, respectively. The concentrations of all pollutants were high in winter and low in summer. However, the concentration of O_³ was high in summer and low in winter. Atmospheric oxidative O_^x remained at a relatively stable level throughout the year and was dominated by NO_² in winter and O_³ in other seasons. The concentration of PM_^2.5 was positively correlated with that of NO_² and CO, followed by SO_² and O_^x (in summer), which indicated that the local vehicle exhaust emission was an important source of atmospheric particulates. The temperature was positively correlated with O_³, and negatively correlated with other pollutants. Relative humidity, wind speed and rainfall were negatively correlated with SO_², NO_², CO, PM_^2.5 and PM_¹⁰, which showed that the pollutants were easy to diffuse under strong wind and wet deposition condition. However, CO was less affected by humidity and rainfall. This study provides a theoretical foundation for controlling atmospheric pollution in Hangzhou City.

Phytoremediation is a low-cost and eco-friendly technology by using plants to uptake and accumulate heavy metals from contaminated soils. Intercropping is a simple and feasible method of agricultural management which was applied here to increase plant production and facilitate the efficiency of phytoremediation.
A pot experiment based on an intercropping system of moso bamboo seedlings and Sedum plumbizincicola was conducted to investigate its influence on the growth of plants, transfer ability of heavy metals in the system of soil and plant, and the effect on accumulation of Cu, Cd and Zn in different parts of plant.
The results showed that the root biomass of S. plumbizincicola which was intercropped with moso bamboo in 2 mm soil decreased significantly, and the biomass of both stems and leaves of moso bamboo which was intercropped with S. plumbizincicola in 5 mm soil was also declined clearly compared with that of moso bamboo in 2 mm soil. Moreover, the biomass of moso bamboo seedlings and S. plumbizincicola was reduced as compared with those of CK (monocropping), which suggested that intercropping led to competition between moso bamboo seedlings and S. plumbizincicola. Intercropping resulted in the decline of heavy metal uptake for the roots of moso bamboo seedlings and the competition between Cd and Zn in the roots of S. plumbizincicola, while
it improved both upward transport by roots, but there were differences in the process for different metals accumulated in different parts (stem or leaf) of moso bamboo seedlings. In addition, contrast to monocropping, Cu, Cd and Zn accumulation in any part of moso bamboo seedlings decreased distinctly, but Cd and Zn accumulation in the overground part of S. plumbizincicola increased by 57% and 82% in 5 mm soil.
In sum, the intercropping system of moso bamboo and S. plumbizincicola shows the potential of upward transfer of heavy metals, and it also has positive impacts on Cu, Cd and Zn accumulation.

The relationship between plants and environment is mainly reflected in the life history, morphology, phenology, physiology of plants. Different kinds of plants have different adaptation strategies. The southeastern of Qinghai-Tibet Plateau is among the highest forest line distribution areas and one of the most obvious climate change areas in the world. Understanding ecological and climatic indicators of the forest line in this area can offer a foundation for analyzing
the possible changes in the future climate scenario. By means of research on the basic characteristics and physiological indicators of Abies georgei var. smithii seedlings on Mt. Shergyla in southeastern Tibet, we hope to discover the response of Abies georgei var. smithii seedlings to the environment with different altitude gradients, and provide basic evidence for further explaining the response of Abies georgei var. smithii seedlings to altitude.
In this paper, we collected 350 seedlings of 7-8 years with great growth condition in the range of 3 800-4 400 m above sea level in April 2014. We measured their basic growth indexes, root activity, chlorophyll content, etc., and employed Excel 2013, R3.3.1, SPSS 21.0 and other software to analyze the data.
The results showed that: 1) The optimal growth of Abies georgei var. smithii seedlings was observed at the altitude of 3 900 m. The basic characteristics and chlorophyll content were significantly higher than the other altitudes. 2) At the altitude of 3 800 m to 4 100 m, the soluble protein content, soluble sugar content and root activity of Abies georgei var. smithii seedlings were basically stable, indicating that the environmental stress had no significant effect on the growth of Abies georgei var. smithii seedlings. 3) From the altitude of 4 200 m in the Mt. Shergyla, transition began with the forest line and tree line, and the external environment at the altitude of 4 400 m was harsh. The indexes such as seedling height, root activity and chlorophyll content declined sharply which were greatly affected by environmental stress.
In sum, the growth of Abies georgei var. smithii seedlings is largely affected by the altitude of Mt. Shergyla. The seedlings could not resist the effects of environmental stress in the range of the forest line, which resulted in short seedlings with weak energy and slow growth.

Malachite green (MG) is a typical triphenylmethane dye that has been extensively used in ceramics, dyeing, textile and leather industries, etc. Meanwhile, MG can also be used as insect repellant, insecticide and anti-microbial agents in aquaculture industry. However, it has been reported that MG is difficult to degrade and has potential carcinogenicity and genotoxicity for humans, animals, and microorganisms. As a result, MG has been prohibited from being used in aquaculture by Food and Drug Administration of the United States, United Kingdom, China, European Union, and some other countries. Therefore, to remove MG residue in the aquatic environment, protect human beings and maintain the ecological balance, screening of microorganisms for biodegradation of MG is very necessary and important. Biodegradation of MG by microorganisms has gained more and more attention due to its inexpensive and eco-friendly feature. Raoultella sp., Pandoraea sp., Pseudomonas sp. and Arthrobacter sp. have been reported to have potential ability for biodegradation of MG. The degradation behavior was distinctly affected by culture condition and environmental factors.
In this study, a bacterial strain named as Enterobacter sp. CV-b was isolated, and the characteristics of MG decolorization by Enterobacter sp. CV-b were investigated using single-factor experiments, then the enzymes and metabolites related to MG degradation were detected by ultraviolet-visible spectrophotometry, Fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry technologies, to screen for in situ bacteria with stronger environmental adaptability.
The results indicated that most of the tested carbon sources had no significant effect on decolorization, and starch was the optimal carbon source for promotion of decolorization. In the initial incubation period, the inorganic nitrogen source NH₄Cl slightly inhibited the decolorization of MG, and the inhibition effect became weaker with time. Meanwhile, the inorganic nitrogenm source NaNO₃ could slightly enhance the decolorization of MG. However, most of the organic nitrogen sources significantly enhanced decolorization, and peptone was the optimal nitrogen source for MG decolorization. Under the condition of pH 5.0-10.0 and 20-50 ℃, MG decolorization percentage by the strain CV-b was over 92% after 6 h incubation, indicating this strain has strong environmental adaptability with broad pH and temperature range. After 6 h incubation, MG decolorization percentage by the strain reached 90% with the initial MG concentration below 900 mg/L, suggesting its great potential in highly efficient biodegradation of MG. Besides, Cu²⁺ was observed to inhibit MG decolorization significantly. Enzyme activity data showed that, tyrosinase might be involved in the MG degradation by the strain CV-b. Meanwhile, the results of metabolite analysis indicated that (dimethylamino-phenyl)-phenyl-methanone was one of the major products of MG degradation by the strain CV-b.
In conclusion, this strain has a great potential in the application of MG bioremediation due to its strong environmental adaptability with broad pH and temperature range, and high degradation percentage of MG with high initial dye concentration. Moreover, the related enzyme analysis and metabolite detection will be helpful to understand the mechanism of MG decolorization by the strain CV-b.