Effects of carbon sink fisheries ecosystems

Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 （carbon dioxide） emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO2 is the main component of greenhouse gases and the main culprit of causing the greenhouse effect. The ocean is a huge repository of carbon, water can dissolve a large amount of CO2, in the ocean, a large number of plants and planktonic algae absorb CO2 to produce 02, It is a very large gathering place （sink）. At the same time, CO2 aggregation in the ocean seawater acidity increases, impact on fishery resources, sources and sinks of CO2 were discussed in the paper.

Spatio-seasonal patterns of fish diversity,Haizhou Bay,China

Spatial-seasonal patterns in fish diversity in Haizhou Bay were studied based on stratified random surveys conducted in 2011.Principal component analysis was conducted to distinguish different diversity components,and the relationships among 11 diversity indices were explored.Generalized additive models were constructed to examine the environmental effects on diversity indices.Eleven diversity indices were grouped into four components:(1) species numbers and richness,(2) heterogeneous indices,(3) evenness,and(4) taxonomic relatedness.The results show that diversity indices among different components are complementary.Spatial patterns show that fish diversity was higher in coastal areas,which was affected by complex bottom topography and spatial variations of water mass and currents.Seasonal trends could be best explained by the seasonal migration of dominant fish species.Fish diversity generally declined with increasing depth except for taxonomic distinctness,which increased with latitude.In addition,bottom temperature had a significant effect on diversity index of richness.These results indicate that substrate complexity and environmental gradients had important influences on fish diversity patterns,and these factors should be considered in fishery resource management and conservation.Furthermore,diversity in two functional groups(demersal/pelagic fishes) was influenced by different environmental factors.Therefore,the distribution of individual species or new indicators in diversity should be applied to examine spatio-seasonal variations in fish diversity.

Effects of temperature and salinity on the development of embryos and larvae of the veined rapa whelk Rapana venosa(Valenciennes, 1846)

The major population of the veined rapa whelk Rapana venosa （Valenciennes, 1846）, which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature （16-34℃ at salinity 30） and salinity （5-45 at 25℃） on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34℃, the lower temperature limit was 16~C, the longest mean shell length （1 193＋17 pan） occurred at 25℃ and the highest survival rate 72.28%＋5.62% was observed at 28℃. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15-40, the longest mean shell length （855-4-9 μm） and the highest survival rate 72.93%~4.85% were both observed at 35. This study demonstrated that, during the egg-mass stage, temperature and salinity regimes influence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa.

Significant Effects of Fishing Gear Selectivity on Fish Life History

Over the past few decades, extreme changes have occurred in the characters of exploited fish populations. The majority of these changes have affected the growth traits of fish life history, which include a smaller size-at-age, an earlier age-at-maturation and among others. Currently, the causes of these life history traits changes still require systematic analyses and empirical studies. The explanations that have been cited are merely expressed in terms of fish phenotypic adaptation. It has been claimed that the original traits of fish can be recovered once the intensity of exploitation of the fish is controlled. Sustained environmental and fishing pressure will change the life history traits of most fish species, so the fish individual's traits are still in small size-at-age and at earlier age-at-maturation in exploited fish populations. In this paper, we expressed our view of points that fishing gear has imposed selectivity on fish populations and individuals as various other environmental factors have done and such changes are unrecoverable. According to the existing tend of exploited fish individual's life history traits, we suggested further researches in this field and provided better methods of fishery management and thereby fishery resources protection than those available early.

Fish community diversity in the middle continental shelf of the East China Sea

The status of fishery stocks in the coastal waters of China is far from ideal, mainly due to climate change and the impacts of human activities （e.g., pollution and overfishing）. Thus, the restoration and protection of fishery resources have become critical and complex. The stability and balanced structure of the fish community is a basic foundation for the protection of fishery resources. Based on data collected from bottom trawls by the R/V Beidou in continental shelf of the East China Sea in November 2006 and February 2007, changes in the composition and diversity of fish species and functional groups were analyzed. The research area was divided into offshore waters and inshore waters by the two-way indicator species analysis （TWIA）. The results showed that the dominant species were different between offshore waters and inshore waters and also varied with the survey time. The most abundant family was Sciaenidae and Teraponidae in November 2006, Sciaenidae, Engraulidae and Triglidae were most abundant in February 2007. The species belonged mainly to mobile piscivores （G6）, benthivores/piscivores （G4）, benthivores （G3） and planktivores （G1）, and the dominant species in November 2006 were commercial species （e.g. Larimichthys polyactis and Trichiurusjaponicus）, but small-sized species were dominant in February 2007 （e.g., Harpadon nehereus, Benthosema pterotum, Champsodon capensis, and Acropoma japonieum）. The species diversity showed a similar trend as the functional group diversity. Stations with higher diversity were mainly distributed in inshore waters in February 2007, whereas higher diversity was found in offshore waters in November 2006. The highest biomass and species number were found in G6 group, followed by the G4, G5 and GI groups. The distribution of the number of individuals of each functional group showed the opposite trend as that of the biomass distribution. In addition, the size spectra were mainly concentrated around 3-29 cm, and the individual number of fish species gradually decreased with the increase in body size, but the relative biomass showed a moderate fluctuation in each size class. These changes showed that species with faster growth rate and earlier maturity age became dominant in continental shelf of the East China Sea. So the variations in biological characteristics of fish should be fully considered in maintaining sustainable utilization of fishery resource.

Impacts of distorted fishery statistical data on assessments of three surplus production models

We evaluated the effect of various error sources in fishery harvest/effort data on the maximum sustainable yield （MSY） and corresponding fishing effort （EMsv） using Monte Carlo simulation analyses. A high coefficient of variation （CV） of the catch and effort values biased the estimates of MSY and EMsv. Thus, the state of the fisheries resource and its exploitation was overestimated. We compared the effect using three surplus production models, Hilborn-Waters （H-W）, Schnute, and Prager models. The estimates generated using the H-W model were significantly affected by the CV. The Schnute model was least affected by errors in the underlying data. The CVof the catch data had a greater impact on the assessment than the CV of the fishing effort. Similarly, the changes in CV had a greater impact on the estimated maximum sustainable yield （MSY） than on the corresponding estimate of fishing effort （EMsY）. We discuss the likely effect of these biases on management efforts and provide suggestions for the improvement of fishery evaluations.

Variation in the distribution of wintering anchovy Engraulis japonicus and its relationship with water temperature in the central and southern Yellow Sea

In the present study,we investigated a shift in the spatial distribution of wintering anchovy(Engraulis japonicus)and its relationship with water temperature,using data collected by bottom trawl surveys and remote sensing in the central and southern Yellow Sea,during 2000–2015.Our results indicate that the latitudinal distribution of wintering anchovy varied between years,but there was no consistent pattern in the direction of change(north or south).Wintering anchovy did not move northward with increasing water temperature.However,the latitudinal distribution of wintering anchovy correlated well with 10°C and 11°C isotherms.The results of both a one-step and a two-step generalized additive model indicated that water temperature was associated with both presence and biomass of wintering anchovy.This paper is the fi rst to systematically examine the relationship between anchovy distribution and water temperature using a variety of techniques.All the fi ndings confi rm the impact of water temperature on wintering anchovy distribution,which has important implications for the continued management of the anchovy resource and the enhancement of marine fi shery resources in the Yellow Sea,especially as the climate changes.However water temperature only partly explains the species distribution of anchovy,and stock characteristics also aff ect fi shery distribution.Therefore,other factors should be considered in future research.

Current status and prospect of fisheries resource enhancement in Tianjin

Based on the data of releasing and enhancement of Tianjin Bohai Sea Fisheries Research Institute,this study has entirely summarized the experiences and achievements on releasing and enhancement works in Tianjin since 2006.Since 2006,Tianjin has launched the first multi-proliferation and release activity with"Fenneropenaeus chinensis"as the leader.So far,more than 22 varieties have been proliferated,among which crustaceans are dominant.There are significant ecological,economic and social benefits.Both national and international development trends of releasing and enhancement are summarized,and demands and objective of industrial development are proposed.

A new algorithm for estimating gillnet selectivity

The estimation of gear selectivity is a critical issue in fishery stock assessment and management.Several methods have been developed for estimating gillnet selectivity,but they all have their limitations,such as inappropriate objective function in data fitting,lack of unique estimates due to the difficulty in finding global minima in minimization,biased estimates due to outliers,and estimations of selectivity being influenced by the predetermined selectivity functions.In this study,we develop a new algorithm that can overcome the above-mentioned problems in estimating the gillnet selectivity.The proposed algorithms include minimizing the sum of squared vertical distances between two adjacent points and minimizing the weighted sum of squared vertical distances between two adjacent points in the presence of outliers.According to the estimated gillnet selectivity curve,the selectivity function can also be determined.This study suggests that the proposed algorithm is not sensitive to outliers in selectivity data and improves on the previous methods in estimating gillnet selectivity and relative population density of fish when a gillnet is used as a sampling tool.We suggest the proposed approach be used in estimating gillnet selectivity.

Length-weight relationships for six freshwater fish species in Iran

The aim of this study is to report the length-weight relationship parameters （a and b） for some economically important fish species from Iranian freshwaters. The length-weight relationships （LWR） are calculated for six freshwater fish species collected during 2006 and 2007 in Iran. The values of the exponent b in the LWR （W=aL^b） vary between 2.985 and 3.543. The LWR with high correlation coefficient （r^2） is significant for all the species. These parameters axe of great importance to evaluate the relative condition of populations, biology, species management and their fisheries and stock assessment. The application of the length-weight relationships presented here should be limited to the observed length ranges.

Fishery Resources in Arid Zone Mangroves in Gulf of Kachchh, Gujarat, Northwest Coast of India

The finfish and shellfish resources were assessed quantitatively and qualitatively in regard to their abundance in creek waters at three sites within a period of two years, fi＇om January 1999 to December 2000, in the western mangrove areas of Kachchh. The catch rate varied from 0.69 to 6.99kg·h^-1. It was low during monsoon （July to October）, which could be due to the freshwater-flow-induced salinity reduction in all the sites. Among 38 species recorded, 5 were shellfish and 33 were finfish. The spawning period of fishes was found to be during summer and early monsoon period （May to August）. Surface water temperatures varied from 17℃ to 37 ℃. Salinity values varied from 34 to 44 and the pH ranged between 7 and 8.9. Variation in dissolved oxygen content was from 3.42 to 5.85 mL L^-1. The high fishery densities in these semi arid mangrove creek areas were recorded during monsoon and early winter season.

Estimating time-based instantaneous total mortality rate based on the age-structured abundance index

The instantaneous total mortality rate(Z) of a fish population is one of the important parameters in fisheries stock assessment. The estimation of Z is crucial to fish population dynamics analysis,abundance and catch forecast,and fisheries management. A catch curve-based method for estimating time-based Z and its change trend from catch per unit effort(CPUE) data of multiple cohorts is developed. Unlike the traditional catch-curve method,the method developed here does not need the assumption of constant Z throughout the time,but the Z values in n continuous years are assumed constant,and then the Z values in different n continuous years are estimated using the age-based CPUE data within these years. The results of the simulation analyses show that the trends of the estimated time-based Z are consistent with the trends of the true Z,and the estimated rates of change from this approach are close to the true change rates(the relative differences between the change rates of the estimated Z and the true Z are smaller than 10%). Variations of both Z and recruitment can affect the estimates of Z value and the trend of Z. The most appropriate value of n can be different given the effects of different factors. Therefore,the appropriate value of n for different fisheries should be determined through a simulation analysis as we demonstrated in this study. Further analyses suggested that selectivity and age estimation are also two factors that can affect the estimated Z values if there is error in either of them,but the estimated change rates of Z are still close to the true change rates. We also applied this approach to the Atlantic cod(G adus morhua) fishery of eastern Newfoundland and Labrador from 1983 to 1997,and obtained reasonable estimates of time-based Z.

Fishery stock assessment of Kiddi shrimp (Parapenaeopsis stylifera) in the Northern Arabian Sea Coast of Pakistan by using surplus production models

Pakistani marine waters are under an open access regime. Due to poor management and policy implications, blind fishing is continued which may result in ecological as well as economic losses. Thus, it is of utmost importance to estimate fishery resources before harvesting. In this study, catch and effort data, 1996-2009, of Kiddi shrimp Parapenaeopsis stylifera fishery from Pakistani marine waters was analyzed by using specialized fishery software in order to know fishery stock status of this commercially important shrimp. Maximum, minimum and average capture production ofP. stylifera was observed as 15 912 metric tons （mr） （1997）, 9 438 mt （2009） and 11 667 mt/a. Two stock assessment tools viz. CEDA （catch and effort data analysis） and ASPIC （a stock production model incorporating covariates） were used to compute MSY （maximum sustainable yield） of this organism. In CEDA, three surplus production models, Fox, Schaefer and Pella-Tomlinson, along with three error assumptions, log, log normal and gamma, were used. For initial proportion （IP） 0.8, the Fox model computed MSY as 6 858 nat （CV=0.204, R^2=0.709） and 7 384 mt （CV=0.149, R^2=0.72） for log and log normal error assumption respectively. Here, gamma error produced minimization failure. Estimated MSY by using Schaefer and Pella-Tomlinson models remained the same for log, log normal and gamma error assumptions i.e. 7 083 mt, 8 209 mt and 7 242 mt correspondingly. The Schafer results showed highest goodness of fit R2 （0.712） values. ASPIC computed MSY, CV, R2, FMsv and BMsv parameters for the Fox model as 7 219 nat, 0.142, 0.872, 0.111 and 65 280, while for the Logistic model the computed values remained 7 720 mt, 0.148, 0.868, 0.107 and 72 110 correspondingly. Results obtained have shown that P. stylifera has been overexploited. Immediate steps are needed to conserve this fishery resource for the future and research on other species of commercial importance is urgently needed.

A preliminary discussion on the construction of marine ranching in Tianjin

Introduces the development connotation,development ideas,practice history and future prospects of Tianjin Ocean Ranch under the background of the development of national marine pastures.Combine the development process of China's marine pastures with the practice of Tianjin Ocean Ranch,the development characteristics of Tianjin marine pastures are analyzed.It is concluded that,for the future construction of Tianjin Ocean Ranch,we can focus on promoting the transformation of marine development mode to recycling,and construct a marine space development pattern of land-sea coordination and human-sea harmony,in order to accelerate the realization of Tianjin's"One Base and Three Districts"objective.We will make greater contributions to the quality of a well-off society and the creation of a beautiful new environment in Tianjin.Modern marine pastures are a long-term,complex and scientific systematic project that requires great attention and attention from all walks of life.

Geospatial Mapping of Fisheries Profile of West Bengal of India through GIS

In the age of information and technological advancements, location-awareness is becoming a key feature in management of natural resources. Geospatial mapping is a location based study and is a part of intelligence GIS which is expected to be useful tool for fisheries scientists, aquatic resource managers and policy planners in developing and planning strategies for fisheries resources of the country. In this context, a study was performed where mapping of fisheries profile of West Bengal was carried out using GIS tool having critical geographic dimensions. For this purpose, at the core of the system fisheries data of West Bengal were accessed and integrated from different sources at district level. Data were tabulated using Microsoft Excel and then joined to digitize Map of West Bengal to enable mapping using Arc info 9.3 GIS software. This was further synchronized and integrated to generate four thematic maps based on different criteria. The map dealing with fisher folk population and their occupation contains the searchable criteria as regards to the fishermen population as well as their classified categories according to their occupation. The map dealing with West Bengal fish production contains fish production, fish seed production district-wise and growth rate for 2004-2008. The third map contains district-wise water resources and reservoir areas along with brackish water. With this mapped information, planners and various stakeholders will have readily accessible district level data on various components of fisheries of West Bengal, thereby facilitating better planning, management and development of the fisheries sector.

Progress on Research and Construction of Marine Ranching along the Coast of Shandong Province of China

As a new fishery mode of low-carbon economy, marine ranching has played an important role in promoting sustainable development of fishery and construction of ocean economic zone in China. Since the year of 2000, environment improvement, stock enhancement and mariculture development have been given very high degree of importance along the coast of Shandong Province of China. Studies and tests on artificial reefs and marine ranching, including effect investigation of artificial reefs set up in Jiaonan coastal areas in 1980s, hydrodynamic characteristics experiment of artificial reef, study on material and configuration of artificial reef models, algae transplantation and seaweed beds construction, stock enhancement and releasing etc., have been carried out in recent years. Furthermore, the Restoration Plan of Fishery Resources of Shandong Province has been implemented since the year of 2005, which greatly boosted the construction of artificial reefs and marine ranching along the coast of Shandong. By June of 2010, the total investment on the construction of artificial reefs and marine ranching is over $77 million USD. One hundred artificial reef districts, with total area about 33,350,000 m2 have been set up. The construction of marine ranching along the coast of Shandong Province has been in certain scale and the economic, social and ecological effects are obvious.

Perspectives:Gene expression in fisheries management

Functional genes and gene expression have been connected to physiological traits linked to effective production and broodstock selection in aquaculture, selective implications of commercial fish harvest, and adaptive changes reflected in non-commercial fish populations subject to human disturbance and climate change. Gene mapping using single nucleotide polymorphisms （SNPs） to identify functional genes, gene expression （analogue microarrays and real-time PCR）, and digital sequencing technologies looking at RNA transcripts present new concepts and opportunities in support of effective and sustainable fisheries. Genomic tools have been rapidly growing in aquaculture research addressing aspects of fish health, toxicology, and early development. Genomic technologies linking effects in functional genes involved in growth, maturation and life history development have been tied to selection resulting from harvest practices. Incorporating new and ever-increasing knowledge of fish gehomes is opening a different perspective on local adaptation that will prove invaluable in wild fish conservation and management. Conservation of fish stocks is rapidly incorporating research on critical adaptive responses directed at the effects of human dis- turbance and climate change through gene expression studies. Genomic studies of fish populations can be generally grouped into three broad categories： l） evolutionary genomics and biodiversity; 2） adaptive physiological responses to a changing environment; and 3） adaptive behavioral genomics and life history diversity. We review current genomic research in fisheries focusing on those that use microarrays to explore differences in gene expression among phenotypes and within or across populations, information that is critically important to the conservation of fish and their relationship to humans [Current Zoology 56 （1）： 157-174, 2010].

Study on the legal system of the summer fishing moratorium in the Bohai Sea

In1995,the official implementation of the system of summer fishing moratorium was one of the most important systems in the field of marine fishery management in China.It mainly focuses on offshore fishery resources and the specific situation of the fishery production,taking special protection of marine fishery resources system in order to alleviate the pressure on the marine fishery resources and the marine environment caused by the ever-increasing of fishing vessels and the excessive fishing intensity.The implementation of this system is a major policy for promoting the sustainable development of marine fishery resources in China.This paper conducts a special legal study on the system of summer fishing moratorium in the Bohai Sea,aiming to further improve the system and protect marine fishery resources and marine ecological environment.

Trophic interactions, ecosystem structure and function in the southern Yellow Sea

The southem Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an ecosystem model to analyze the trophic interactions and ecosystem structure and function to guide sustainable development of the ecosystem. Atrophic mass-balance model of the southern Yellow Sea during 2000-2001 was constructed using Ecopath with Ecosim software. We defined 22 important functional groups and studied their diet composition. The trophic levels of fish, shrimp, crabs, and cephalopods were between 2.78 and 4.39, and the mean trophic level of the fisheries was 3.24. The trophic flows within the food web occurred primarily in the lower trophic levels. The mean trophic transfer efficiency was 8.1%, of which 7.1% was from primary producers and 9.3% was from detritus within the ecosystem. The transfer efficiency between trophic levels II to III to IV to V to 〉V was 5.0%, 5.7%, 18.5%, and 19.7%-20.4%, respectively. Of the total flow, phytoplankton contributed 61% and detritus contributed 39%. Fishing is defined as a top predator within the ecosystem, and has a negative impact on most commercial species. Moreover, the ecosystem had a high gross efficiency of the fishery and a high value of primary production required to sustain the fishery. Together, our data suggest there is high fishing pressure in the southern Yellow Sea. Based on analysis of Odum＇s ecological parameters, this ecosystem was at an immature stage. Our results provide some insights into the structure and development of this ecosystem.

Local-Scale Governance： A Review of the Zambian Approach to Fisheries Management

Despite Zambia＇s recent policies for optimizing sustainable management of fisheries, their success has been modest in practice. Artisanal and industrial fleets have led to decline in fish catches in the presence of currently prescribed management possibilities. Among other factors, excessive fishing and unsustainable fishing methods attributed to common property and free access to the resources are key. The country adopted co-management approach to fisheries management in the 1990s with a view to improve the fisheries stocks through community enforcement of fishery management regulations. Neither the success of co-management has been easy to measure nor its results appreciated. In view of overfishing, it is required to continue providing a range of empirical evidence of area-specific co-management interventions as basis for designing realistic and innovative solutions for the nation. This implies that new policies and institutions need to be developed by research to understand fisheries systems and better promote sustainable trajectories. The following review recommendation to central government is a coherent approach that uses and crystallizes the multiple interests and skills of co-management stakeholders. Most stakeholder groups have been involved in an ad hoc fashion through workshops, public meetings and consultative processes mainly organized by Department of Fisheries. Stakeholders should be involved from the design of the process to each step in the process, including the ongoing monitoring and evaluation. A form of memorandum of understanding is suggested. This will formally set out a process that acknowledges each stakeholder＇s interests and provide forums to facilitate discussion, consultation and monitoring of management activities.