The effects of saline irrigation water and mannitol on the growth and content of essential oil, photosynthetic pigments, soluble sugars, proline, Na, macroelements (N–P–K) and microelements (Mg–Zn–Fe–Mn) of lemon balm ( L.) plants were investigated. Saline irrigation water decreased certain growth characters (total leaf area, leaf number, and total fresh and dry mass). The photosynthetic pigments (chlorophylls and , total carotenoids) and mineral content (N–P–K–Mg–Zn–Fe–Mn) also decreased as saline irrigation water level increased. Saline irrigation water promoted the accumulation of essential oil content and its main components (citronellal, citronellol and geranyl acetate) as well as total soluble sugars, proline and Na contents. The plants treated with saline irrigation water × mannitol resulted in higher plant growth, essential oil, total soluble sugars, proline, macro and micronutrient values than those treated with saline irrigation water alone, photosynthetic pigments and Na demonstrated an opposite trend.
The effects of nitrogen (N) deposition on (Sw.) Bird. subsp. (Mitt.) Hyvoenen, a species of moss widely distributed in South China, were investigated. Plots subjected to a gradient of N treatments were established in 3 habitats with different illumination and humidity conditions. N was sprayed onto plots with NH NO solutions, at doses equivalent to 20, 40 and 60 kg N ha , in 4 applications during May 2006 and January 2007. The results suggest that high N deposition affects both carbon (C) and N metabolism of subsp. , as well as the interaction between them. On the other hand, the sensitivity of the moss varied according to the humidity and light conditions. Moss in a habitat with high humidity and moderate light was more tolerant to an N deposition increase than moss in a habitat with low humidity and low light, as the latter was extremely sensitive to an increase in N deposition. 论文研究了华南地区广泛分布的刺边小金发藓拟刺亚种在模拟氮沉降条件下的生理响应 实验于2006年5月至2007年1月期间 在光照与湿度条件不同的三个生境设置样地 各样地均设立4个氮处理水平 (对照 20 40和60 kg N hm ) 以一定浓度的 NH NO 溶液分四次喷洒至样地 结果表明: 高氮处理会对刺边小金发藓拟刺亚种的碳、氮代谢造成显著影响 另一方面 苔藓植物对于模拟氮沉降的敏感性也随着光照与湿度条件的不同而表现出较明显的差异 在高湿度及适度光照的条件下 苔藓植物对于加氮的耐受力较强 而在低湿度及高光照强度的条件下 苔藓植物对于氮处理表现出极高的敏感性
In order to investigate the effect of organic volatiles from poplar species on the host plants orientation of , the essential oil in the 2–3 years old branches from the sapling or mature trees of Carr. and Carr. L. were extracted using the steam distillation method. The chemical composition and relative content in essential oil from those branches was analyzed by GC–MS. The main components contained in those volatiles from the four kinds of branches are mainly aromatic compounds such as 1,2 cyclohexanedione, 2 cyclohexene 1 one, p xylene and 1,2,3 trimethylbenzene and so on. The relative content of aromatic compounds contained in branches from saplings was higher than that contained in branches from old tress. EAG response and behavioral reaction of L. to those four kinds of distillated essential oil were tested. The results shown that male and female adults of L. shown significant choice behavior and strong olfactory response to those essential oil distillated from branches of Carr. and Carr. L.. The EAG bioassay of L. to 10 kinds of monomers compounds which had relative higher contents was tested. The results shown that the EAG response of female adults of L. to 1 mol L p-xylene was intensest and reached 1.027 mV, the strength of their EAG response to 0.1 mol L phenol took the second place. The EAG response of male adult of L. to 1 mol L p-xylene was strongest and reached to 0.824 mV, the strength of their EAG response to 1 mol L salicylaldehyde took the second place. In the choice behavior test of L. adult to monomeric compound carried out in ‘Y’ type olfactometer have found that female and male adult of L. all appeared obvious positive taxis to 0.1 mol L p-xylene. The selection rate of female and male adults ware (76.7 ± 4.1)% and (71.7 ± 2.6)%, respectively. The selective reaction to 0.1 mol L 1,2-cyclohexanedione and 2-cyclohexene-1-one were not obviously than that to 0.1 mol L p-xylene. The male and female adult of L. appeared repelling behavior to 0.1 mol L salicylaldehyde.
The structure and dynamics of periphytic algae in Jinyang Lake, the largest man-made lake in Taiyuan, Shanxi, have been studied by examining the periphytic algae samples collected from four sampling stations, during March 2006 to February 2007. In total, 227 species of periphytic algae (including varieties), belonging to three divisions, 27 families, 62 genera, have been identified. Diatoms were the dominant periphytic algae group. Taken the Shannon–Weaver, Margalef and Simpson diversity index together, it showed obvious temporal and spatial dynamics among different seasons and different sampling stations. The highest periphytic community structure evenness appeared at sampling station I in spring, summer and autumn, while at sampling station III in winter. The average biomass of periphytic algae varied from seasons. Our data showed that major factors affecting the periphytic algae in Jinyang Lake was water temperature, nutrient levels as well as human activities. In addition, the main effect caused by thermal power plant has been discussed.
In the present work, we evaluated the feeding selectivity of starved on two freshwater green algae and . Compared to . , food quality of . are better in food palatability (cell size and digestibility), but poor in nutritional content (total carbon content). . was starved for 0 and 8 d, and then was allowed to graze on a mixture of . and . with following proportion: 5 × 10 : 35 × 10 cells ml , 20 × 10 : 20 × 10 cells ml and 35 × 10 : 5 × 10 cells ml . The results indicated that the ingestion rate and filtration rate of starved . , comparing with satiated groups, on . increased significantly, while, inverse trends was observed in . . Base on selectivity coefficient of . , we observed that when . was in satiation . will be preferred, while, . will be selected when . was in starvation, and moreover, these foraging behaviors were not influenced by the relative food abundance of each green alga. Therefore, a tradeoff between food palatability (physical makeup) and food nutritional content (chemical composition) can be hypothesized in the foraging behavior of . , which is modified by the starvation of feeder. High valuable food is always selected by . as predicted by optimal foraging theory. However, when . is in satiation food diets with adequate size and easy digestibility will be preferred, while, those foods with relatively higher lipid or total carbon content will be selected when . is in starvation.
is one of the main shrubs that were used in desertification control project in China. Large area (2700 km ) of plantation, especially more than 10 years plantation, has degraded outside Minqin oasis, northwest China. It is hard for plantation to utilize ground water deeper than 20 m and to use precipitation with only mean annual 116.2 mm and uneven distribution in growing season. Thus, soil water might be the main water source of plantation. Moreover, following grows up, more soil water will be needed. In this study, it is hypothesized that plantation would utilize deeper soil water as its age increased. Water use characteristics of different ages of plantation (2 years, 5 years, 10 years, 20 years and 30 years) were examined by stable oxygen isotope technology outside Minqin oasis in July 2009. The δ O values of water in xylem, six different depths of soil (20 cm, 30 cm, 50 cm, 100 cm, 150 cm and 200 cm), rain and ground water (replaced by well water) were compared to determine major water source of plantation. Meanwhile, the density, height, length and width of individuals were measured, and soil water contents were examined at the six depths in these plantation. The results showed that in 5 years plantation, soil water content in 50 cm was significantly lower than moving sand dune and other ages, and soil water content in 100–200 cm was lower than moving sand dune and 2 years plantation. The main depth that used soil water increased as the age increased; 2 years mainly used 50–200 cm soil water; 5 years used 100–200 cm soil water and started to use ground water; 10 years used 150–200 cm soil water and ground water, plant density of declined and soil water content recovered gradually; 20 years and 30 years mainly used ground water. Therefore, excessive consumption to soil water of high plant density might be one of the reasons for the degradation of plantation. The critical age of plantation is 5 years outside Minqin oasis because it consumed excessive soil water. If the density of 5 years plantation was not decreased by selective cutting at present, it would degrade as the stand age increased later. It is suggested that initial density of new plantation outside Minqin oasis must be reduced to slow down its consumption of soil water in future, and then the stability of plantation could be sustained for a longer time.
Mining activities lead to the destruction of soil properties and productivity. Accomplishment of soil properties which existed before mining can be used for successful reclamation of the mined out area. With this aim proposed bauxite mines in the Eastern Ghats, India, were studied with respect to the exchangeable fraction of Na, K, Li, Ca and Mg. Na in the soils ranged from 4 to 82 mg/kg, K 15.2–746 mg/kg, Ca 119.6–2875.2 mg/kg, Li 1.2–14 mg/kg and Mg 349.8–2391.9 mg/kg. The elements studied varied significantly among the locations (ANOVA, < 0.05). Cation Exchange Capacity (CEC) was negatively correlated with most of the variables. Principal Component Analysis (PCA) accounted for 95.6% of the total variance. PC1 (first principal component) formed of pCa, rMg, Mg:Ca, rCa and pMg, indicated Ca type enrichment in the system. PC2 and PC3 reflected the influence of SAR, pNa, rNa and Na, and Mg and CEC, respectively. The study, aimed at documenting the background concentrations of base cations in the Araku soil system, India, will be useful in later years during mine restoration programme. It would also form a base document for the mine managers during mine restoration.
The interface between decaying plant residues and soil is a focus for soil ecological processes because of resources from the residues diffusing into the soil, and microfauna that proliferate in the adjacent soil. Given that the recovery of soil function following disturbance depends on immigration, colonization and establishment of exotic organisms from adjacent un-disturbed habitats, and the availability of bio-available resources, we hypothesized that the soil–litter interface could contribute to soil functional stability. In laboratory pot trials, soil was separated into two parts by a mesh bag with the inner section amended, or not amended, with rice straw; an outer layer of unamended soil, adjacent to the litter (1.5 cm thick, either heated or not), provided a soil–litter interface. This enabled us to examine the dynamics of dissolved organic carbon (DOC), mineral nitrogen, microbial biomass carbon (MBC), nematode assemblages and functional stability during 35 days incubation. Either 1 mm or 5 μm meshes were used, which allowed nematodes to migrate (SR1) or not (SR5) through the mesh to the soil–litter interface; thus also enabling us to evaluate the role of nematodes in soil functional stability. Higher DOC and MBC but lower mineral nitrogen concentrations were found at the soil–litter interface. Heating increased the availability of soil resources such as mineral nitrogen and DOC, but decreased the MBC and total nematode abundance in the soil. The soil–litter interface was characterized by a higher abundance of nematodes, particularly microbivores, regardless of mesh aperture or disturbance. The difference in nematode abundance between SR1 and SR5 indicated that nematode propagation, due to resource diffusion and nematode migration through the mesh, contributed to the changing numbers of microbivorous nematodes depending on incubation time. The soil functional stability was calculated as a relative change in the functioning of short-term barley decomposition. Soil functional resistance, defined as the instantaneous effect of disturbance on decomposition measured on the first day, was highest in the SR5 treatment. However, soil functional resilience, defined as the recovery of soil function over the whole incubation period (35d), was highest in the SR1 treatment, which is most probably attributed to the functioning of microbivorous nematodes. Our results suggest that small-scale spatial heterogeneity, due to organic residue decomposition, can help maintain soil functions following disturbance.
The current cropping system of excessive tillage and stubble removal in the northwestern Loess Plateau of China is clearly unsustainable. A better understanding of tillage and stubble management on surface soil structure is vital for the development of effective soil conservation practices in the long term. Changes in surface soil structure and hydraulic properties were measured after 4 years of stubble management (stubble retained vs. stubble removed) under contrasting tillage practices (no-tillage vs. conventional tillage) in a silt loam soil (Los Orthic Entisol) in Dingxi, Gansu, the northwestern Loess Plateau, China. Our results indicated that after 4 years small but significant changes in soil properties were observed amongst the different tillage and stubble treatments. Surface soil (0–5 cm) under no-tillage with stubble retention had the highest water stability of macroaggregates (>250 μm), soil organic carbon (SOC) and saturated hydraulic conductivity. Significant correlation was found between water stable macro-aggregates and soil organic carbon content, indicating the importance of the latter on soil structural stability. The improvement in soil structure and stability was confirmed by higher soil hydraulic conductivity measurements. Consistently higher was detected in the no tillage with stubble retained soil compared to other treatments. Therefore, no-tillage with stubble retention practice is an effective management technique for improving physical quality of this fragile soil in the long term.
Application of remote sensing (RS) and geographical information system (GIS) techniques has been increased in natural sciences. In fact, it is inevitable applying of these techniques in vegetation studies due to the existence of some problems in traditional methods (e.g. sampling, calculation, analysis and so on). On this scope, scientists must have sufficient information about the efficiency of these techniques as a useful tool in their studies. This study aims to evaluate the IRS-P6 LISS III and Landsat ETM efficiency in plant groups’ identification. In order to this purpose, 143 training samples were collected from areas that showed homogenous composition of plant species in at least area of 3600 m (60 × 60 m). Coordinates of these training samples were recorded using a GPS device and transferred to a GIS database. Also, ENVI 4.2 package has used to process and analyze the satellites data. Several methods of processing such as; spectral separability, supervised classification and assessment of classification accuracy were used in order to gain a satisfy evaluation of the data efficiency. The results indicated that net farming of alfalfa and community have the most separability on the satellite images (1.99 for Landsat and 2 for IRS). Against, the least separabilities on the Landsat data were between and communities (1.57) and between and (1.53) on the IRS data. According to these results, it is concluded that the satellite data are somedeal able to identify plant groups when vegetation communities are sufficiently homogenous, abundant and spectrally and ecologically separable.
Allelopathy of diterpenoids extracted from plants of the genus on three common species of soil ciliates, , and , was studied by acute toxicity test, sub-lethal effect test and morphological observation. Acute toxicity test showed that there was remarkable toxicity of the diterpenoids on the individuals of the three soil ciliate species, and there was close correlation between toxicity and concentration of the diterpenoids. 12 h-LC values of the diterpenoids on the individuals of , and were 161.40 mg L , 94.80 mg L and 83.70 mg L respectively, and 24 h-LC values were 114.90 mg L , 92.30 mg L and 65.80 mg L separately. Sub-lethal effect test of soil ciliates suggested that there existed significant inhibition of the diterpenoids on population growth of the three ciliates with dose-dependant relationships, population density and growth rate of the test group was obviously lower than that of the control group. Morphological observation indicated that diterpenoids affected the body shapes of the three ciliates and made them shorter and thicker, and the higher the concentration of diterpenoids, the greater the affection. The results are of great significance for understanding the functions of ciliates and their relationships to other organisms, and for the application of allelopathy in biological pest control in the soil ecosystems.
Arbuscular mycorrhizal (AM) fungi colonize the roots of over 80% of terrestrial plant species, forming mutually beneficial symbioses. During the colonization process, symbiotic partners recognize each other, and undergo observable morphological and physiological changes; indicating that symbiosis formation involves multiple factors that are finely regulated. Sometimes host plants generate a transient, weak, defense response. This response and its down-regulation play a very important role in the development of AM symbioses. Although AM fungi can infect a wide range of host root tissues, which host defense may play a crucial role is hypothesized from the fact that hyphal expansion is only observed in the root cortex. We discuss five defense mechanisms. (1) The degradation of exogenous elicitors. The host’s weak defense response may be due to the degradation of the exogenous elicitor chitin, or the prevention of release of an endogenous inductor from the plant cell wall. (2) The inactivation of defense signal molecules. Some defense signal molecules such as hydrogen peroxidase, salicylic acid (SA), and jasmonic acid (JA), are inactivated in host plants. This helps to avoid the turn-on of defense-related genes and facilitate mycorrhizal formation. (3) The regulation of plant hormones and plant photosynthates. Plant hormone levels and plant photosynthate metabolism both change during AM colonization. These mechanisms need further exploration. (4) Changes in levels of phosphorous (P), and (iso)flavonoids. High P levels can induce some defense genes to express hydrogen peroxidase, chitinase, and glucanase. These gene products can repress colonization by AM fungi. The plant defense response regulatory effect for different (iso)flavonoids varies, and their levels are regulated by P. (5) The suppressed expression of symbiotic genes. Some symbiosis-related genes inhibit plant defense responses, but it is still unclear which mechanisms underlie gene regulation. We provide here a theoretical basis for research into AM symbiosis that may promote study of host plant resistance and the mechanisms of symbiosis formation. We provide a deeper insight into the signal transduction pathways of mycorrhization that will aid understanding and analysis of plant defense mechanisms in the AM context. The on-going development of genome sequencing technology will contribute greatly to the detailed study of symbiosis-related genes, and pathogenesis-related protein genes. These related genes may be induced to express corresponding proteins, be repressed, postpone expression or even shutdown, or both may work together to form symbioses. Elucidation of these features will help us understand the roles that plant defenses play in mycorrhizal formation; providing an unprecedented opportunity for research into mycorrhizal molecular biology and the interaction of symbiotic partners, and allowing the underlying mechanisms to be gradually uncovered.
In the north of China, wheat plants are often stressed by heat and high light during grain-filling stage, which leads to injury in photosynthetic apparatus and decline in photosynthetic rate. In order to develop a method to protect photosynthetic apparatus in wheat leaves subjected to heat and high light stress, the effects of SA (salicylic acid) and FSBA (5′- -fluorosulfonylbenzoyl adenosine) on PK (protein kinase) activity, D1 protein degradation and the performance of PSII were investigated in present work. Our results showed that PK activity enhanced under heat and high light stress and declined when stress was removed. FSBA pretreatment resulted in marked decreases in PK activity and D1 protein level, suggesting a correlationship between degradation of D1 protein and phosphorylation. After 2 h of stress, D1 protein level in water-pretreated leaves decreased to 79% of control and then recovered to 81% after 3 h of recovery. This clearly indicated that the damage of D1 protein induced by heat and high light stress was reversible. Compared to the control, SA pretreatment could not only increase PK activity, retard the degradation of D1 protein during heat and high light stress, but also accelerate the recovery of D1 protein level when the stress was removed. Correspondingly, / (maximum photochemical efficiency of PSII), (actual photochemical efficiency of PSII), ETR (electron transfer rate) and Pn (net photosynthetic rate) in SA-treated leaves were higher than that in leaves of control under both stress and non-stress conditions. Taken together, our results revealed that SA pretreatment could significantly alleviate damages of heat and high light stress on D1 protein and PSII of wheat leaves, and accelerate restoration of photosynthetic function.
Grassland recovery and reconstruction are critical to ecological restoration in the Chinese Loess Plateau (CLP). Investigating changes in soil organic carbon density (SOCD), soil organic carbon (SOC) storage, and the rate of SOC sequestration is very important to assess the effect of ecological recovery and estimate the capacity of soil carbon sequestration. Here, we present the data of SOCD, SOC storage, and SOC sequestration rate from grasslands conversion from farmlands in the CLP. Our results indicate that: (1) The average SOCD (0–100 cm) in sites continued cultivation (CC), cultivation abandonment at 1999 (AC-99) and cultivation abandonment at 1989 (AC-89) is 6.00, 21.64 and 22.23 kg m , respectively. SOCD in sites AC-99 and AC-89 is significantly higher than that in site CC and the average SOCD of China (10.53 kg m ), which indicates that vegetation restoration is benefit to increase soil carbon storage as well as preserve soil and water in this area. (2) The SOC storage (0–100 cm) in sites CC, AC-99 and AC-89 is 60.02, 216.35 and 222.32 kg m , respectively. Results of ANOVA indicate that SOC storage of AC-99 is significantly higher than that of CC, while SOC storage of AC-89 is significantly higher than that of AC-99 at the depth of 0–50 cm ( < 0.001). It suggests that the capability of soil carbon sequestration increases after vegetation restoration, which is mainly due to the increase of plant roots. (3) The rate of SOC sequestration varies at different depths, which is high at the depth of 0–50 cm while low at the depth of 50–100 cm. This is probably due to the accumulation of plant root in the surface layer, which is the main controlling factor of SOC in this area. Our results indicate that the SOCD and SOC storage increase with vegetation restoration in our study site significantly.
Habitat fragmentation has been cited as one of the critical reasons for biodiversity loss. Establishing connected nature reserve networks is an effective way to reduce habit fragmentation. However, the resources devoted to nature reserves have always been scarce. Therefore it is important to allocate our scarce resources in an optimal way. The optimal design of a reserve network which is effective both ecologically and economically has become an important research topic in the reserve design literature. The problem of optimal selection of a subset from a larger group of potential habitat sites is solved using either heuristic or formal optimization methods. The heuristic methods, although flexible and computationally fast, can not guarantee the solution is optimal therefore may lead to scarce resources being used in an ineffective way. The formal optimization methods, on the other hand, guarantees the solution is optimal, but it has been argued that it would be difficult to model site selection process using optimization models, especially when spatial attributes of the reserve have to be taken into account. This paper presents a linear integer programming model for the design of a minimal connected reserve network using a graph theory approach. A connected tree is determined corresponding to a connected reserve. Computational performance of the model is tested using datasets randomly generated by the software GAMS. Results show that the model can solve a connected reserve design problem which includes 100 potential sites and 30 species in a reasonable period of time. As an empirical application, the model is applied to the protection of endangered and threatened bird species in the Cache River basin area in Illinois, US. Two connected reserve networks are determined for 13 bird species.
Climate change alters regional water and carbon cycling, which has been a hot study point in the filed of climatology and ecology. As a traditionally “water-rich” region of China, Yangtze River Basin plays an important role in regional economic development and ecosystem productivity. However, the mechanism of the influence of climate change on water and carbon cycling has been received little attention. As a coupling indicator for carbon and water, the water use efficiency (WUE) is widely used, which indicates the water consumption for carbon sequestration in watershed and regional scale. A lot of studies showed that climate change has significantly affected the water resource and production of the ecosystems in Yangtze River Basin during the period of 1956–2006, when great climate variations were occurred. To better understand the alternation pattern for the relationship between water and carbon cycling under climate change at regional scale, the WUE and the spatiotemporal variations patterns were simulated in the study area from 1956 to 2006 by using the Integrated Biosphere Simulator (IBIS). The results showed that the WUE spatial pattern had the annual and seasonal variations. In general, the average annual WUE value per square meter was about 0.58 g C/kg H O in Yangtze River Basin. The high WUE levels were mainly distributed in the eastern area of Sichuan, western area of Jiangxi and Hunan, and the highest value reached 0.88 g C/kg H O. The lowest WUE’s were mainly located in the western area of Sichuan and Qinghai with the lowest values reaching to 0.36 g C/kg H O. The WUE in other regions mostly ranged from 0.5 to 0.6 g C/kg H O. For the whole study area, the annual WUE slowly increased from 1956 to 2006. The WUE in the upper reaches of Yangtze River increased based on the simulated temporal trends, which mainly located in the western area of the Sichuan Basin; the WUE of the middle reaches of Yangtze River had increased slightly from 1987 to 1996, and then decreased from 1996 to 2006; the lower reaches of Yangtze River always had smaller WUE’s than the average from 1956 to 2006. The spatiotemporal variability of the WUE in the vegetation types was obvious in the Yangtze River Basin, and it was depended on the climate and soil conditions, and as well the disturbance in its distribution areas. The temporal variations of WUE among different vegetation types had similar trends but different in values. The forest type had higher WUE than any other vegetation types ranging from 0.65 to 0.8 g C/kg H O. The WUE of shrubland ranged from 0.45 to 0.6 g C/kg H O. The WUE of tundra was the lowest, indicating the differences in plant physiology. The consistence of the spatial pattern of WUE with the NPP indicated that the regional production of Yangtze River Basin increased based on the water resources prompted and vegetation restoration. We found the drought climate was one of critical factor that impacts the alteration of WUE in Yangtze River Basin in the simulation.
Coastal wetland is located in the active interface between land and sea, which is one of the richest biodiversity habitats, while it is seriously disturbed and destroyed by anthropogenic activities in both terrestrial and marine parts. Habitat serves as the basis for organism survival, providing food, shelter, water, space and so on, and habitat degradation and loss caused by intense anthropogenic activities is widely considered as the main reason for biodiversity decline and loss. However, there is still limited study on the evaluating methods of coastal wetland habitats, especially for those in a large scale. In this study, methods for evaluating coastal wetland habitat quality, including selecting indicators, setting value assignment criteria and weights were discussed systematically, a method of coastal wetland habitat quality evaluation was established, and the habitat quality in Quanzhou Bay was also evaluated as a case study. The present study provided a new concept and method to assess quantitatively habitat status, indicate the ecological status and its change, and also reflect and predict indirectly the ecological impact of human activities. Referring to the habitat evaluation system (HES) developed by United States in the mid 1970s, the evaluation method was established by thorough analysis of the characteristics of coastal wetland. The habitat indicators were selected in terms of three habitat factors as follows: chemical factors, including dissolved oxygen (DO), phosphate in seawater, sulfide in sediment, and regional priority pollutants; physical factors, including landscape naturalness index and coastline artificialization index; biological factors, including invasive species risk and area ratio of invasive alien species. Weights were established by Analytic Hierarchy Process, combined with several-round expert evaluation. Evaluation criteria providing principles for value assignment of each indicator, were established referring to previous standards and related researches. The final result for assessing habitat quality was indicated and stated by the value of Habitat Quality Index ( ), which is the weighted sum of each indicator. Habitat quality increased with the value, with value ranging from 0 to 100. The established evaluating method was applied to assess the habitat quality of Quanzhou Bay, located in the southeast coastal zone of Fujian Province, with a total area of 136.4 km , which is an important bay in Fujian. Quanzhou Bay wetland is a typical coastal wetland with diverse wetland habitats, including mangrove, estuary, island, aquaculture ponds, salt pan, shallow sea, mud flat and so on. The Quanzhou Bay is now seriously suffering environmental problems, e.g. eutrophication due to great discharge of domestic, agricultural and industrial wastewater, rapid urbanization and reclamation resulting in decreased wetland area, and the invasion of alien species. The evaluation results showed that the habitat quality index value was 68.13, 57.99 and 51.23 in 1989, 2002 and 2008, respectively, indicating that the habitat degraded gradually. The five major factors that led to decline of value were phosphate in seawater, lead in sediment, landscape naturalness index and coastline artificialization index and area ratio of invasive alien species. Therefore, in order to improve and maintain habitat quality, it is urgent to control pollution, large-scale reclamation and Spartina invasion in Quzhou Bay.
To understand the physiological and ecological responses of marine fishes to the change of water temperature, newly-hatched larvae of Yellowtail clownfish were reared in captivity at water temperatures of 23, 26 and 29 °C till they completed the metamorphosis to juvenile phase, and larval survival, development, growth and feeding were evaluated during the experimental period. The results showed that water temperature influenced the physiological performance of larvae of significantly. The survival and growth rates of larvae of increased significantly with the increase of water temperature from 23 to 29 °C ( 0.05), indicating that FR influenced growth rate significantly in larvae of . This study demonstrated that the physiological responses of larvae of to the change of water temperature and confirmed that water temperature influenced larval survival, development, growth and feeding significantly. This study suggests that the decline of larval survival and growth rates, extension of pelagic larval duration and reduction of larval feeding at lower temperature have ecological impacts on larval dispersal and metamorphosis, juvenile settlement and population replenishment in in the wild.