Benthic diatoms from three river catchments across Hainan Island’s five national natural reserves were examined to explore the community structure and spatial distribution patterns. Among the 174 benthic diatom species in 55 genera observed from the 30 sampling sites, the dominant genus is Achnanthes with relative abundance of 52.3%. Cluster analysis and non-metric multidimensional scaling (NMDS) analysis reveal a distinct geographic pattern, which differentiate the western Bawangling, western Jianfengling, the middle Yinggeling and Wuzhishan, and the eastern Diaoluoshan with various characteristic benthic diatom communities. Diatom diversity is the lowest in the western mountain zone but highest in the middle mountain zone. The contrast in benthic diatom community between the western mountains, and the middle and eastern mountains possibly suggests a climate control by southeast Asian monsoon. At most of the 30 study sites, the dominant species are indicators of clean water quality, such as Achnanthidium minutissimum, A. rivulare, Achnanthes subhudsonis, Gomphonema clevei and Navicula cryptotenella; whereas only a few sites contain Gomphonema parvulum and Aulacoseira ambigua, indicators of high levels of nutrients. This indicates that the rivers investigated are in good condition, but one should be cautioned against the eutrophication trend at a few sites with intensified human activities.

The relationship of nitrate and sea surface temperature (SST) was firstly established by using the observed data of the northern South China Sea. The validity of the in situ data was also examined by the data from MODIS-SST. The adjusted data demonstrated a negative relationship between the nitrate and sea surface temperature (R²=0.7126). The 8-day and monthly composite SST values by remote sensing have been used to estimate the nitrate concentration of sea surface in the South China Sea. The 8-day composite sea surface concentration ranged from 0 to 3.3167 μM, and monthly composite from 0 to 2.0590 μM. The estimated nitrate concentration in the South China Sea was exactly in accord with the in situ and historical data.

Concentrations of heavy metals in surface sediment collected from twelve stations along Guishan Island, the Pearl River Estuary in August were determined. The results indicated that the pollution of heavy metals was at the middle level, and the mean contents of Pb, Cr, Ni, Cu, Zn, Mn, Fe and Ca were 40.06, 31.29, 14.17, 30.67, 100.18, 599.76, 24728.10 and 18677.36 mg/kg, respectively. Accumulating coefficients and potential ecological risk index showed that the sequence of accumulating coefficients of six heavy metals in surface sediment of Guishan Island was Cu﹥Pb﹥Zn﹥Mn﹥Cr﹥Ni, and the coefficients of Cu, Pb, Zn and Mn were higher than 1. The degree of potential ecological risk of heavy metals in this sea area presented a low level, and spatially the most serious one was at station S11. Principal component analysis (PCA) was applied to estimate the sources of heavy metal contamination. Results suggested that the first two components accounted for 44.38% and 42.61% of the total variance, respectively, indicating that industrial and domestic wastewater and erosion of rocks were the main sources of heavy metal contamination.

Production of amylase, protease, lipase, and cellulose of four marine yeasts was compared using differential medium plate method, and the enzyme activities were also analyzed in this research. The results showed that Candida colliculosa DY11-1 could secrete amylase, protease and lipase, and their activities were 181.4, 123.1 U/mL and 54.2 U/mL, respectively. Pichia sp DY11-6 and Candida parapsilosis DY07-1 could secrete amylase and protease. Their amylase activities were 108.1 and 96.5 U/mL, and their protease activities were 35.1 and 128.4 U/mL, respectively. Rhodotorula glutinis DY02-3 did not secrete the four extracellular enzymes. Feed extracts of Tilapia mossambica were used as aquaculture organic pollutants to compare the degradation ability of the four marine yeasts. The results showed that Candida colliculosa DY11-1 possessed the strongest degradation capacity. The concentration of COD, TN and TP in the tested water decreased from 27.60, 12.22 and 2.67 mg/mL to 15.73, 7.59 and 1.40 mg/mL after 9 days, respectively, with the degradation rates of 43.0%, 37.8% and 47.5%. It indicated that DY-11 had potential application value in improving water quality of aquaculture.

Effects of growth phase, temperature, irradiance and nitrogen source on the amino acid oxidase (AO) activity of Prorocentrum donghaiense, a causative organism of large-scale harmful algal blooms (HABs) along the coastal waters of East China Sea, were investigated in the laboratory. The results showed that P. donghaiense displayed higher amino acid oxidase activity in N-depleted conditions. AO activity of P. donghaiense was detected at the temperatures ranging from 15 to 30℃, in which AO activity was significantly higher at lower temperatures (15℃-20℃) than that at higher temperatures(25℃-30℃) (p<0.05), and the maximum value was observed at 20℃. Although AO activity was relatively higher (0.38 to 0.47 fmol/(h·cell)) at higher irradiances (50-100 μmol/(m²·s)), AO activity was still up to 0.28 fmol/(h·cell) at irradiance of 2 μmol/(m²·s¹). Nitrogen source exhibited a significant impact on AO activity of P. donghaiense. The highest AO activity (0.44 fmol/(h·cell)) was observed when alanine was used as the sole nitrogen source, and the lowest AO activity (0.22 fmol/(h·cell)) was recorded in the combination of ammonium and alanine. It suggested that temperature, irradiance and nitrogen source were key environmental factors regulating AO activity of P. donghaiense. P. donghaiense is not only capable of utilizing free amino acids effectively, but also flexible in adapting to broad temperature and lower irradiance, which may play important roles in the formation and duration of P. donghaiense blooms.

The flowing sediment typed river water in the Lingang New City, Shanghai was restored with the continuous adjustable Alternanthera philoxeroides and Myriophyllum verticillatum submerged vegetation net beds. The bioremediation efficiency was evaluated by 4-month continuous monitoring of total nitrogen(TN), nitrite nitrogen(NO₂-N), nitrate nitrogen(NO₃-N), total phosphorus(TP), phosphate(PO4-P) and Secchi depth(SD) from June to December in 2011. The results showed that the transparency and water quality of the eutrophic sediment typed river were improved significantly. The TN, NO₂-N, NO₃-N, TP, PO₄-P concentrations of the eutrophicate water were decreased by 69.58%, 67.91%, 84.48%, 62.26%, 82.61% and 45.48%, 58.32%, 76.56%, 43.12%, 73.68%, respectively with Alternanthera philoxeroides and Myriophyllum verticillatum submerged vegetation net beds. The transparency of sediment typed river water was increased by 18% and 26%, respectively with Alternanthera philoxeroides and Myriophyllum verticillatum submerged vegetation net beds. It indicated that Alternanthera philoxeroides submerged vegetation net bed was better than Myriophyllum verticillatum submerged vegetation net bed in reducing nutrient. While Myriophyllum verticillatum submerged vegetation net bed was better than Alternanthera philoxeroides submerged vegetation net bed in increasing transparency of the sediment typed river water. So combining both Myriophyllum verticillatum and Alternanthera philoxeroides submerged vegetation net beds would increase bioremediation efficiency for removing nutrients and sediment in rivers.

Some hydrocarbon-degrading bacterial strains were isolated from the oil-contaminated mangrove soil on Qi-ao Island of Zhuhai City through selective enriched culture. There were three strains (named Z1, Z2 and Z3) being able to grow with hexadecane as sole carbon and energy resources. After 5 days culture, the degradation rates of Z1, Z2 and Z3 were 63.4%, 82.5% and 78.3%, respectively. The morphological and physiological-biochemical identification, 16S rDNA sequence analysis, and phylogenetic study showed that the strain Z2 belonged to genus Acinetobacter.

Yellow catfish (Pelteobagrus fulvidraco) is an important cultured catfish in China, and suffering from various diseases. Immunoglobulin M (IgM) is an important molecule against pathogens in fish immune response. In order to elucidate its expression pattern and mechanism during the period of immunological reaction for prevention of fish diseases, it is necessary to obtain enough IgM protein for preparation of anti-IgM specific antibodies. Therefore, the recombinant expression plasmid (IgM-pQE30) of yellow catfish was constructed with the IgM heavy chain coding sequence fragment cloned from the catfish linking the prokaryotic expression vector pQE30 after complete digestion of sequencing plasmid (IgM heavy chain/pMD-18T) and pQE30 by two endonucleases Sph 1 and Kpn 1. Then the recombinant plasmid was transferred into the host bacterium Escherichia coli M15, and induced to express fusion protein, which was confirmed by means of SDS-PAGE and Western blotting. A 62 kDa protein was greatly induced in unsoluble status in M15, and confirmed to be the recombinant protein (target protein) using monoclonal antibody against 6xHis tag in Western blotting. The recombinant protein was expressed in the greatest quantity at 30℃ for the induction of 8 hours with 0.2 mmol/L IPTG. The IgM heavy chain fusion protein can be greatly expressed in the recombinant plasmid expression system under the most suitable induction conditions mentioned above. This lays a foundation for further researches on the IgM of yellow catfish.

The effects of CO₂ concentration and nitrogen source KNO₃ addition on the growth and major metabolic substances accumulation of Porphyridium sp. UTEX 637 were researched by culturing it in the Φ6×60cm cylindrical glass photobioreactor. The results showed that appropriate concentration of CO₂ could significantly promote the algal biomass and the content of exopolysaccharides, water-soluble protein and total lipids. The most suitable CO₂ concentration was 1%. The maximum cell dry weight of experimental group was 8.14 g/L(1%CO₂), which was 4.93 times of the control group. The maximum output of exopolysaccharides was 238.38 mg/L, which was significantly higher than the control group. Adding nitrogen source KNO₃ had apparent stimulative effect on the algal cell growth, exopolysaccharides, and water-soluble protein content. The maximum cell biomass and exopolysaccharides content were 1.5 and 1.25 times of the control group, but it did not contribute to the total lipids accumulation.

The specimens of Tilapia zillii for individual fecundity study were collected every month from January 2011 to December 20011 in the Dongjiang River. It was found that T. zillii was a multiple spawner and the breeding seasons were from early May to the end of October. The sizes of mature eggs in females were from 1.20 to 1.90 mm. Absolute fecundity(F)ranged from 4913 to 13129 eggs, with the mean of 7991 eggs. Eggs produced in one spawning (F_b) ranged from 1997 to 6369 eggs, with the mean of 4114 eggs. The individual fecundity to standard length (F_L) varied from 49 to 83 eggs/mm, with the mean of 62 eggs/mm, and the individual fecundity to body weight (F_W) varied from 66 to 154 eggs/g, with the mean of 98 eggs/g. Fecundity showed curvilinear relationships with standard length (L), e.g., F=2.186L^1.6886 and F_b=0.7243L^1.7796, and linear relationships with body weight (W) and weight of eviscerated fish (W_n), e.g., F=50.184W + 3627.3, F_b=25.008W + 1952.2, F=58.783W_n+ 3553.4, and F_b = 28.939W_n +1942.

Based on the monitored data, the trend of water quality and eutrophication extent at each monitoring site of Dongchang Lake during 2004-2011 were analyzed by single factor index, Nemerow index method and trophic state index method. The results showed that the single factor index of hydrogen ion concentration(pH) and dissolved oxygen(DO) displayed a fluctuating upward trend, and the water quality was conformed with the water quality standard of Class IV. The single factor index of chemical oxygen demand(COD_Cr) and total nitrogen(TN) displayed a fluctuating declining trend; total phosphorus(TP) displayed a fluctuating upward trend, and the three single factor indices were higher. Total nitrogen(TN) had the greatest impact on water quality. Nemerow index of Nanguan, Xiguan Bridge showed upward trends, suggesting that the water quality got worse. Nemerow index of Beiguan, Dongguan Bridge showed a declining trend, demonstrating the water quality became better. Eutrophication of each monitoring site was in light-middle eutropher level during 2004-2010, which reached mesotropher level up to 2011. The eutrophication levels of Dongguan and Beiguan Bridge were higher than those of Xiguan and Nanguan Bridge.

Preliminary study on bird resources and community structures among the typical urban woodlots of Fuling in Chongqing was conducted using the method of line transect census and chirm identification during February to April 2009. The results showed that during 40 times survey, 2 245 individuals and 37 species of birds were recorded, which belonged to 2 orders, 17 families, 30 genera, with 26 species listed in the national protection for useful, important economic, and scientific research value birds, and 1 specie listed in convention international trade pact on endangered species (CITES). According to bird fauna, 25 species were oriental birds, 8 species palaearctic birds, and 4 species widespread birds. From type of residence, 31 species were residents, 4 species summer migrants, and 2 species winter migrants. The highest indexes of diversity and evenness were both in the Taiji Forest Park (2.3239, 0.6974), but the least in the Yijiaba Square Garden(1.0307, 0.4691). The maximum of Sorenson index of similarity analysis between the Baozicheng Park and the Yijiaba Square Garden was 63.16%. In addition, the G-F index of birds in Fuling urban woodlots was 0.5100.

The quantitative analysis on dominant species in the process of sand-mining wetland restoration was studied. A total of 21 dominant species of niche breadth and niche overlap were measured in the Xizhuojiaying area. The results showed that mesophyte Artemisia lavandulifolia, Inula japonica, Potentilla supina, Artemisia scoparia, Bidens pilosa occupied a wide niche width, and distributed relatively widely. Phragmites australis and Eleocharis congesta wetland plants niche width was slightly smaller; wetland plants Typha orientalis, Typha minima, Zizania aquatic, Lythrum salicaria occupied narrow niches. The niches overlap index indicated there were 78 species counterparts having niche overlaps, accounting for 57.4% of the total 136, which indicated that niche overlap was prevalent among dominant species. In other words, half of plant populations had similarities in the use of resources. In general, niche overlap was larger with the wider population niche, and niche overlap was larger with more similar ecological characteristics as well. The results of this study will provide a scientific support for sand-mining wetland restoration.

In order to systematically examine the vertical distribution of chlorophyll a and nutrients, and to provide the original data for marine ecosystem simulation, water quality and marine ecosystem data were collected in four different seasons from October 2007 to September 2008. The sampling site was located at the central point between Dalajia Island and Sangzhou Island. The study examined the vertical distribution and seasonal variation of chlorophyll a and nutrients, and analyzed the correlation between chlorophyll a and dissolved inorganic carbon (DIC), PO₄-P, and SiO₃- Si. The results showed that the variations of chlorophyll a, DIN, PO₄-P and SiO₃-Si were 0.50-5.80 mg·L^-1, 0.023-0.159 mg·L^-1, 1.606-19.69 μg·L^-1 and 0.065-1.13 mg·L^-1, respectively. The seasonal variations of chlorophyll a were higher in summer, spring, and winter but lower in autumn. SiO₃-Si and DIN were similar, which were higher in summer, autumn, and winter, but lower in spring. PO₄-P showed a reverse trend, which was the lowest in summer. The impact of DIN and SiO₃-Si on chlorophyll a was low in vertical variation. The PO₄-P and chlorophyll a showed a positive correlation, indicating that the impact of PO₄-P on chlorophyll a was great.

A new method was put forward to measure the total N by hyperspectra technology. 148 fir soil samples were collected using a FieldSpec®3 spectrometer. All samples were divided randomly into 2 groups, one group with 100 samples used as calibrated set, and the other with 48 samples used as validated set. The original spectra were pretreated by different methods, and then the PLS model was established with the spectra in the range of 350-2350 nm to compare the different pretreated methods. It was found that the background information and noise of the spectra could be eliminated by the method of wavelet denoising combined with multiplicative scatter correction effectively, with the calibration R-square (C-R²) Prediction R-square (P-R²) 0.891 and 0.885, respectively. In order to optimize the result, the pretreated spectra were analyzed using the principal component analysis(PCA), and the top 4 principal components were used as the input variables for the least square support vector regression( LS-SVR) model. The C-R²and P-R² of LS-SVR model increased to 0.921 and 0.917, respectively, higher than those of PLS model, which indicated LS-SVR algorithm was more accurate. The result showed that it is feasible to estimate the nitrogen content of fir soil with hyperspectra technology, and the estimation model can be improved by the pretreatment method of wavelet denoising combined with multiplicative scatter correction and the modeling algorithm of LS-SVR.

Based on 69 soil sample data, soil features, spatial pattern and the environmental factors were analyzed with multiple statistical methods. Results showed that water content, content of soil porosity, total phosphorus, organic matter and total nitrogen decreased significantly from upper layer to lower layer; while pH, active phosphorus and bulk density changed irregularly. All soil samples could be clustered into 2 types according to their physical and chemical characteristics: one type distributing mainly in the main stream and branches in the upper part of basin showing slight acidity and high organic and total nitrogen content; and the other type distributing mainly in the middle and lower part of basin with slight alkalescence and low organic matter and total nitrogen. Redundancy analysis showed that altitude, annual precipitation, annual average temperature and distance to river mouth were the main environmental factors influencing the riparian soil in the Taizi River Basin

Based on the Landsat TM/ETM+ images and field survey data, the characteristics changes of land-cover pattern and spatial variation have been studied with the aids of 3S techniques in the source regions of the Yellow River since the mid-1980s. Then change trends of spatial pattern were analyzed in the study area. Influencing factors of ecological environment diversion in the source areas were discussed. The results indicated that patch density changes of land types were observed in the source regions of the Yellow River. The dominant grassland was destroyed to some extent in the recent 20 years. The climate in two source region has become warmer and drier in the recent 20 years due to the global warming; the regional land cover change of spatial structure is obvious. The alpine environment and trend of the climatic changes were the decisive factors affecting grassland ecosystem.

Fejervarya limnocharis was used as a model animal, and its activities were investigated in the farmland of Tuchang Village of Bishan Town, Rui’an Wenzhou of Zhejiang Province for one month, so as to study the influence of post-hibernation and temperature on the activity and body size of F. limnocharis. Our results are as follows. (1) No significant difference in the body size of F. limnocharis was found at different times in a month. Air temperature was not related to body size, but it showed positive correlation to the active numbers of F. limnocharis in the field. (2) Investigation on the number of active F. limnocharis for 4 days showed that there was significant difference between the activity in the forenoon and afternoon. The number of active F. limnocharis in the forenoon was much lower than that in the afternoon, while body size of F. limnocharis was not significantly different between the forenoon and afternoon. Air temperature was not significantly related to body size, but positively correlated to the number of active F. limnocharis. (3) We analyzed the data of active number between long-term and short-term field investigation using single factor analysis of covariance with air temperature as the covariate, and found that the linear regressions of the two group data showed parallelism, while the intercept differences were significant. Therefore, we conclude that air temperature is a very important ecological factor which affects the number of active F. limnocharis during post-hibernation in the field.

It is increasingly recognized that planting Eichhornia crassipes is one of effective methods for polluted water purification and aquatic ecosystem restoration. In order to explore the integrative impact of E. crassipes cultivation on water environment quality, we monitored water environment quality in E. crassipes planting area in the Dianchi Lake from April 2010 to March 2011, by comparing with the control group (non-planting E. crassipes). The results showed that E. crassipes cultivation reduced water pH value, transparency, light intensity, and dissolved oxygen. However, E. crassipes cultivation increased the content of S^2- compared with the control areas. Meanwhile, the influence of E. crassipes cultivation on water environment quality had a monthly fluctuation and it might be related to the growth characteristics of E. crassipes. Our results provide a scientific basis for the control of ecological safety when planting large area of E. crassipes for water purification and aquatic ecosystem restoration.

The growth difference of Anabaena spiroides was investigated using organic phosphorous (β-Glycerol phosphate disodium salt pentahydrate) with different nutrition (high iron concentration, anaerobic leachate, trace element) enrichment. We also determined which nutrient limited the maximum biomass of Anabaena spiroides in the Yanghe Reservoir and assessed the interaction between phosphorus and iron. The results showed that phosphorus limited the growth of Anabaena spiroides, as did iron in the Yanghe Reservoir. Moreover, the effect of phosphorus was more significant than that of iron. When the concentration of phosphorus was 0.1 mg/L, after the addition of iron, Anabaena spiroides had the maximum biomass. When the concentration of phosphorus was 0.02 mg/L, there was no interaction between phosphorus and iron. However, when the concentration of phosphorus was higher than 0.02 mg/L, there was interaction between phosphorus and iron. The growth of Anabaena spiroides was inhibited when adding phosphorus and anaerobic leachate or trace element.

Following the effective implementation of agriculture-related problems and rapid development of rural economics, farmers’ tourism in China is increasing on a considerable scale and will play an important role in the development of tourism economy. As the frontier area of the reform and opening-up in China, tourism market of farmers in Guangdong Province would develop rapidly with the further development of rural economy. Based on the developing situation of rural farmers’ tourism in China, this paper analyzed the strengths, weaknesses, opportunities and threats of farmers’ tourism using the SWOT method through the statistical data and the sampling survey of 1 120 farmers in 14 towns, 7 cities in Guangdong Province. And some countermeasures were also put forward for the market development of farmers’ tourism in Guangdong Province, i.e. strengthening farmers’ tourism propaganda and guiding rational consumption, constructing network of farmers’ tourism and organizing a group to travel, developing tourism products according to actual circumstances and servicing farmer tourists with warmly heart.

Agro-ecological economic system is a kind of a special complex artificial-natural system coupled by the agro-ecosystem and the agricultural economic system, which is also one of the main targets studied in the field of regional human-natural relationship, and the central agent of research on ecological economics. This paper briefly discusses the concept and framework of emergy theory, and then, by literature analysis based on the database of CNKI and Web of knowledge, we concluded that the emergy theory has universal recognition in the field of agriculture, and presents an increasing trend. The emergy theory applied in Agro-ecological economic system research makes some progress in the field of basic theory research, indicators development and empirical studies. However, there are also some key issues that need to be resolved, including agricultural emergy flow diagrams, regional applicable of emergy theory, and comparative research on space-time scale.

The rapid developed man-made forests are greatly improving the eco-environment, but also increasing the risk of forest pests. Ecological regulation, developed from the former strategies, is considered as one of the best strategies for managing forest pests. The development history and the connotation of the strategy of ecological regulation and sustainable pest management in forest were reviewed. Based on several management examples of forest pests, the measures of ecological regulation were categorized into three types, which were based on the forest ecosystem, the pests, and the environment, respectively. The prospects and suggestions were also put forward.