Based on the analysis on the current situation of marine fishery resources and development in Ningde City,this paper plans a spatial pattern for the integration of marine fishery and tourism of the“one belt,three zon...Based on the analysis on the current situation of marine fishery resources and development in Ningde City,this paper plans a spatial pattern for the integration of marine fishery and tourism of the“one belt,three zones,and multiple points”,designs key projects,analyzes the existing problems in the integrated development of fishery and tourism,and proposes relevant countermeasures and suggestions.展开更多
The ultramafic massif of Feragen,which belongs to the eastern ophiolitic belt of Norway,has abundant amounts of chromite ores.Recent studies have revealed a complex melt evolution in a supra-subduction zone(SSZ)enviro...The ultramafic massif of Feragen,which belongs to the eastern ophiolitic belt of Norway,has abundant amounts of chromite ores.Recent studies have revealed a complex melt evolution in a supra-subduction zone(SSZ)environment.This study presents new whole-rock major element,trace element,and platinum-group element chemistry to evaluate their petrogenesis and tectonic evolution.Harzburgites have high CaO,Al_(2)O_(3),TiO_(2),MgO,and REE contents corresponding to abyssal peridotites,whereas dunites have low CaO,Al_(2)O_(3),TiO_(2),MgO,and REE contents corresponding to SSZ peridotites.The Cr^(#)and TiO_(2) of chromian spinels in the harzburgites suggest as much as about 15%–20%melting and the dunites are more depleted with>40%melting.The harzburgites and the dunites and high-Cr chromitites represent,respectively,the products of low-degree partial melting in a back-arc setting,and the products of melt-rock interaction in a SSZ environment.The calculated fO_(2) values for dunites and high-Cr chromitites(-0.17–+0.23 and+2.78–+5.65,respectively and generally above the FMQ buffer)are also consistent with the interaction between back-arc ophiolites with oxidized boninitic melts in a SSZ setting.展开更多
This study was conducted to provide a preliminary assessment of the sea cucumber fishery in Aurora, Philippines. This was conducted from February to June 2013. All sea cucumber gatherers and traders, obtained through ...This study was conducted to provide a preliminary assessment of the sea cucumber fishery in Aurora, Philippines. This was conducted from February to June 2013. All sea cucumber gatherers and traders, obtained through snowball sampling, in each identified sea cucumber fishery area in six coastal municipalities (Baler, Dipaculao, Dinalungan, Casiguran, Dilasag and Dingalan) were interviewed using a structured interview schedule and focused group discussions (FGD). Results revealed that gathering sea cucumbers were accomplished by handpicking, skin diving or compressor diving. A total of 15 commercial species were regularly gathered. Out of this, three species are of very high economic value (≥Php 4000/kg) (Holothuria nobilis, Holothuria scabra, and Actinopyga lecanora). The average number of kilograms harvested per hour per trip ranges from 0.21 (Holothuria fuscopunctata) to 2.71 (Holothuria scabra), while the average size of commonly gathered sea cucumber varies among species with Holothuria lecanora showed an average length (29.26 cm) greater than recorded 24 cm. Processing mainly involves washing, slicing, boiling, drying and packing. Processed sea cucumbers or trepan were sold to middlemen or direct buyers who usually offered higher prices (36.36% up to 69.20%) than the former. Problems encountered by sea cucumber gatherers and traders include a decline in total catch, a shift in area of collection from intertidal zones to deeper waters, an increase in the number of hours spent in finding and gathering sea cucumbers, the use of compressors in gathering, the decline of larger species and gathering of smaller sizes in huge amount, the absence of conservation program for sea cucumber, and the lenient implementation of government policies with regards to coastal resources management.展开更多
[Objective] The paper was scientifically evaluate the potential fishery productivity of Lihu using GIS technology.[Method] The evaluation of potential fishery productivity in Lihu was based on GIS and AHP according to...[Objective] The paper was scientifically evaluate the potential fishery productivity of Lihu using GIS technology.[Method] The evaluation of potential fishery productivity in Lihu was based on GIS and AHP according to the characteristics of fisheries resources in Lihu Lake.The evaluation system included 3 sub-models including water quality,biodiversity and hydrological condition,which totally had 10 indexes.Judgment matrix was constructed based the advices of professors of fisheries resources,and the indicator’s weight were calculated by the process of AHP.The ranking distributing map of potential fishery productivity in Lihu was obtained by the model of raster analysis,raster calculator,spatial overlay and classification models of ARC/INFO.[Result] Potential fishery productivity of Lihu was divided into 4 grades in term of higher,high,general and low,and which covered 2.643 3,3.844 8,1.121 4 and 0.400 5 hm2,respectively.[Conclusion] The study provided theoretical basis for ecological reconstruction of Lihu Lake.展开更多
According to the"National Modern Facility Agriculture Construction Plan(2023-2030)released by the Ministry of Agriculture and Rural Affairs,the"Special Implementation Plan for Modern Facility Fisheries Const...According to the"National Modern Facility Agriculture Construction Plan(2023-2030)released by the Ministry of Agriculture and Rural Affairs,the"Special Implementation Plan for Modern Facility Fisheries Construction"emphasizes the development of circular aquaculture,active expansion of green aquaculture space in facility fisheries,multi-channel development of food sources,comprehensive improvement of the quality,efficiency,and competitiveness of facility fisheries,ensuring stable and safe supply of aquatic products,and better meeting people's needs for high-quality aquatic products and beautiful aquatic ecological environment.Since the implementation of the 14th Five Year Plan for fisheries,facility fisheries have made significant progress.In order to thoroughly implement General Secretary Xi Jinping's important discourse on new quality productivity,conduct in-depth research on the current situation and existing problems of the fishery industry,and put forward suggestions to meet the requirements of high-quality development of the fishery industry in the new era.Therefore,it is crucial to continue practicing the"revitalization of aquatic seed industry"and"big food concept",take multiple measures to"demand food from rivers,lakes,and seas",and expand aquaculture space.Through research,it has been found that research in the field of facility based fisheries is still in its developmental stage.Further exploration is needed on the current status,breeding models,and experimental demonstrations of land-based facility based fisheries,in order to provide a basis for fisheries regulatory authorities to formulate the"15th Five Year Plan"for facility based fisheries.展开更多
Recreational fishery is the combination of traditional fishery and modern leisure activities.Development of recreational fishery resources must be based on related resources,but the present research on recreational fi...Recreational fishery is the combination of traditional fishery and modern leisure activities.Development of recreational fishery resources must be based on related resources,but the present research on recreational fishery is mainly confined to the development of leisure projects,the definition of connotation and scope of recreational fishery resources is rather vague,and there is no precise classification and evaluation system.According to the resources attributes,resources functions,and tourism resources classification,investigation and evaluation standard,recreational fishery resources include a number of different types.Expert Scoring Method and Analytic Hierarchy Process can be used to determine the evaluation factors of recreational fishery resources and their weights,and then make comprehensive evaluation on recreational fishery resources of different regions and types,so as to improve the scientific nature of recreational fishery development.展开更多
In 2011,China put the stock enhancement fishery in the same place as aquaculture,fishing,aquatic product processing and circulation industry,and recreational fishery,i. e. one of the five pillar industries of fishery ...In 2011,China put the stock enhancement fishery in the same place as aquaculture,fishing,aquatic product processing and circulation industry,and recreational fishery,i. e. one of the five pillar industries of fishery economy. Developing the stock enhancement fishery is a strategic measure for restoring and protecting fishery resources,expanding fishery,replacement environment cost,and promoting sustainable development of fishery. At present,cultivation and development of the new rising industry,the stock enhancement fishery,has certain comparative edge,excellent economic foundation and broad development space in China.展开更多
In Cambodia,fishery co-management is an important process to transfer authority and ownership to the communities along the Tonle Sap Lake to manage fishery.This paper aims to determine why the co-management of small-s...In Cambodia,fishery co-management is an important process to transfer authority and ownership to the communities along the Tonle Sap Lake to manage fishery.This paper aims to determine why the co-management of small-scale fishery has not been implemented satisfactorily in the Tonle Sap Lake of Cambodia.The research was primarily based on a household survey among 404 house-holds for quantitative data,equally divided between the Cham(202 households)and Khmer(202 households).Participatory process was also applied to collect qualitative data from key stake-holders.We found that limited interaction among the involved stakeholders,i.e.,unequal distribution of authority and resources co-management,has impeded implementation.The engagement of fisherfolk was influenced by dependence on fishery,law enforcement,and events organized by the communities.While the Khmer had better opportunities to participate in planning at the provincial and district levels,the Cham were only engaged in local development activities initiated by their people.However,the latter evinced a higher rate of satisfaction due to their access tofishery resources and to a large quantity of fishing gear.In the future,efforts should be made to:(1)improve resource and authority sharing among all key stakeholders;(2)urgently resolve issues pertinent to capacity building,insufficient budgets for commune councils(CoCs)and community fishery(CFi);and(3)urge law enforcement regarding illegal fishing.展开更多
This article studies the inshore-offshore fishery model with impulsive diffusion. The existence and global asymptotic stability of both the trivial periodic solution and the positive periodic solution are obtained. Th...This article studies the inshore-offshore fishery model with impulsive diffusion. The existence and global asymptotic stability of both the trivial periodic solution and the positive periodic solution are obtained. The complexity of this system is also analyzed. Moreover, the optimal harvesting policy are given for the inshore subpopulation, which includes the maximum sustainable yield and the corresponding harvesting effort.展开更多
The ocean fishery and the corresponding environment are highly interrelated according tothe production experiences of ocean fishing population. The spatial cluster patterns are constructed using the remote sensed data...The ocean fishery and the corresponding environment are highly interrelated according tothe production experiences of ocean fishing population. The spatial cluster patterns are constructed using the remote sensed data and long-time series fishery production data under the uniform coordinate based on GIS techniques. Thus, the hidden information of distribution regularities between ocean-hydrologic factors and central fishing ground can be extracted from these patterns. It is important to forecast the ocean fishery production.展开更多
Generalized linear models (GLM) and generalized additive models (GAM) were used to standardize catch per unit fishing effort (CPUE) of Ommastrephes bartramii for Chinese squid-jigging fishery in Northwest Pacifi...Generalized linear models (GLM) and generalized additive models (GAM) were used to standardize catch per unit fishing effort (CPUE) of Ommastrephes bartramii for Chinese squid-jigging fishery in Northwest Pacific Ocean. Three groups of variables were considered in the standardization: spatial variables (longitude and latitude), temporal variables (year and month) and environmental variables, including sea surface temperature (SST), sea surface salinity (SSS) and sea level height (SLH). CPUE was treated as the dependent variable and its error distribution was assumed to be log-normal in each model. The model selections of GLM and GAM were based on the finite sample-corrected Akaike information criterion (AICC) and pseudo-coefficient (Pcf) combined P-value, respectively. Both GAM and GLM analysis showed that the month was the most important variable affecting CPUE and could explain 21.3% of variability in CPUE while other variables only explained 8.66%. The interaction of spatial and temporal variables weakly influenced the CPUE. Moreover, spatio-temporal factors may be more important in influencing the CPUE of this squid than environmental variables. The standardized and nominal CPUEs were similar and had the same trends in spatio-temporal distribution, but the standardized CPUE values tended to be smaller than the nominal CPUE. The CPUE tended to have much higher monthly variation than annual variations and their values increased with month. The CPUE became higher with increasing latitude-high CPUE usually occurred in 145°E-148°E and 149°E-162°E. The CPUE was higher when SST was 14-21℃ and the SLH from -22 cm to -18 cm. In this study, GAM tended to be more suitable than GLM in analysis of CPUE.展开更多
Background: Climate change triggered many studies showing that trends and events of environmental conditions can reduce but also accelerate growth at the stand and individual tree level. However, it is still rather un...Background: Climate change triggered many studies showing that trends and events of environmental conditions can reduce but also accelerate growth at the stand and individual tree level. However, it is still rather unknown how climate change modifies the growth partitioning between the trees in forest stands.Methods: Based on long-term girth-tape measurements in mature monospecific and mixed-species stands of Norway spruce(Picea abies(L.) Karst.) and European beech(Fagus sylvatica L.) we traced the effect of the severe droughts in 2003 and 2015 from the stand down to the tree level.Results: Stand growth of Norway spruce decreased by about 30% in the once-in-a-century drought 2015, while European beech was much more drought resistant. Water availability generally amplified size-asymmetric growth partitioning. Especially in case of Norway spruce water availability primarily fostered the growth of predominant trees, whereas drought favoured the growth of small trees at the expense of the predominant ones. We could not detect significant differences between mixed and monospecific stands in this regard.Conclusions: The drought-induced reallocation of growth in favour of small trees in case of spruce may result from its isohydric character. We hypothesize that as small trees are shaded, they can benefit from the reduced water consumption of their sun-exposed taller neighbours. In case of beech, as an anisohydric species, tall trees suffer less and smaller trees benefit less under drought. The discussion elaborates the consequences of the water dependent growth allocation for forest monitoring, growth modelling, and silviculture.展开更多
Na-metasomatism in the form of albitisation is regionally extensive in the Precambrian crust of southern Scandinavia and is particularly widespread in the Bamble Sector, the Kongsberg-Modum Sector and the Norwegian pa...Na-metasomatism in the form of albitisation is regionally extensive in the Precambrian crust of southern Scandinavia and is particularly widespread in the Bamble Sector, the Kongsberg-Modum Sector and the Norwegian part of the Mylonite Zone. Sites of albitisation outside these belts are associated with hy- drothermal breccia pipes and fracture-bound alteration. The albitites are composed of near end-member sodic plagioclase (Ano 5Ab94-99) with minor carbonate (calcite and dolomite), rutile, clinopyroxene (En30Fs21-23W047 49), amphibole (edenite-pargasite), quartz, titanite, tourmaline, epidote (Fe3+ - 0.20 -0.85 a.p.f.u) and chlorite (Mg# = 0.81-0.89). The albitites have been studied in detail in the region around the town of Kragem, and are described as albitisation along veins, as breccias, alhitic felsites, massive carbonate-bearing albitites and megascale clinopyroxene-titanite-bearing albitite. The strong fluid control on their formation is illustrated by the veining and mineral replacement reactions, showing fluid transport by a H20-CO2 fluid rich in Na, depleting Fe and Mg from the host rock, in accordance with calculated mass transfer. A study of the mineralogical replacement reactions in combination with a regional compilation has demonstrated the relationship between metasomatic processes and the for- mation of apatite, ruti|e and Fe deposits. The albitites occur spatially associated with other metasomatic rocks such as scapolitised metagabbros. We document that metasomatism is an important mineral- and rock-forming process in the continental crust, which in the Bamble Sector is a part of the tectonome- tamorphic evolution of the Sveconorwegian orogen.展开更多
Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest ...Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh) can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d) models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM) and shape constrained generalized additive models (SCAM) for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions: We demonstrate that the SCAM approach allows optimal regression modelling flexibility similar to the standard GAM but with the additional possibility of defining specific constraints for the model effects. The longitudinal character of the model allows for tree height imputation for the current status of forests but also for future tree height prediction.展开更多
Jellyfish fishing is a special type of fishery that mainly exists in some countries of East and Southeast Asia. China has the largest jellyfish fishery yield in the world with an annual harvest of around 300 thousand ...Jellyfish fishing is a special type of fishery that mainly exists in some countries of East and Southeast Asia. China has the largest jellyfish fishery yield in the world with an annual harvest of around 300 thousand tons. Liaodong Bay is the most important jellyfish fishery ground in China. However, due to the high benefits of jellyfish fishery, which leads to illegal and out-of-season jellyfish fishing occurring each year in Liaodong Bay. Illegal jellyfish fishery in Liaodong Bay is a typical example of the tragedy of the commons. The key problem is that fishermen seek to an illegally initiate jellyfish fishing as early as possible. In this paper, basing on the data of edible jellyfish's biology and ecology, we mainly analyzed the history of jellyfish fishery in China, especially in Liaodong bay, and then we calculated the carry capacity of edible jellyfish in Liaodong Bay which is about 300 thousand tons one year. This number is equal to the recent annual yield of edible jellyfish in China. Furthermore, basing on the carry capacity and reasonable quotas price analysis, we set up a Jellyfish fishing quotas and deficit quotas buyback system which could be a suitable and effective solution for jellyfish fishery management and development in Liaodong Bay at the underlying roots. Although China is the first country with edible jellyfish aquaculture, the annual yield of jellyfish aquaculture is only one fifth of jellyfish fishing. So, there is a very bright developing prospect about edible jellyfish aquaculture in China.展开更多
[Objective] The aim was to make a comprehensive evaluation and explore strategies on fishery development. [Method] Fishery development in China was analyzed and concerning evaluation system was established based on it...[Objective] The aim was to make a comprehensive evaluation and explore strategies on fishery development. [Method] Fishery development in China was analyzed and concerning evaluation system was established based on its development stage, international competiveness and exportation. In addition, a comprehensive evaluation was made on fishery and countermeasures were proposed considering from government, department of quality control, fishery guild, producing and processing enterprises. [Result] Although progresses have been made in fishery in China, some problems still exist, such as overdose of drug residues, overloading breeding, lower additional value of products, and fewer excellent and famous products. Hence, local governments should give much support to fishery and enhance competitiveness to improve the products in global market; departments of quality control should strengthen supervision and management on fishery products against technical trade barriers; fishery guilds or researching institutions should provide technical support for concerning breeding and processing which should be mainly relied on science and technology. [Conclusion] The research provided references for fishery development.展开更多
Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × ...Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × 4 and a unit frame area of 60 m<sup>2</sup>. A total of 58,201 eggs were collected by 24 monitoring times, of which 30,441 were from Lukou and 27,760 from Hengyang. 3831 fish eggs identify 8 fish species using morphological or molecular biological methods. The results showed that the number of eggs peaked from the 8<sup>th</sup> day to the 24<sup>th</sup> day after the nest entered the water, and then decreased rapidly. There was significant negative correlation between egg number in per m<sup>2</sup> fish nest and days of fish nest (P < 0.01). The economic benefits of artificial fish nests were RMB 11.81 million. The artificial fish nest can not only increase the population of fish, but also has significant economic benefits.展开更多
Surplus production models(SPMs)are among the simplest and most widely used fishery stock assessment models.The catch-effort data analysis(CEDA)and a surplus production model incorporating covariates(ASPIC)are software...Surplus production models(SPMs)are among the simplest and most widely used fishery stock assessment models.The catch-effort data analysis(CEDA)and a surplus production model incorporating covariates(ASPIC)are softwares for analyzing fishery catch and fishing effort data using nonequilibrium SPMs.In China Fishery Statistical Yearbook,annual fishery production and fishing effort data of the Yellow Sea,Bohai Sea,East China Sea,and South China Sea have been published from 1979 till present.Using its catch and fishing effort data from 1980 to 2018,we apply the CEDA and ASPIC to evaluate fishery resources in Chinese coastal waters.The results show that the total maximum sustainable yield(MSY)estimate of the four China seas is 10.05-10.83 million tons,approximately equal to the marine fishery catch(10.44 million tons)reported in 2018.It can be concluded that China’s coastal fishery resources are currently fully exploited and must be protected with a precautionary approach.Both softwares produced similar results;however,the CEDA had a much higher R2 value(above 0.9)than ASPIC(about 0.2),indicating that CEDA can better fit the data and therefore is more suitable for analyzing the fishery resources in the coastal waters of China.展开更多
Background: Generalized height-diameter curves based on a re-parameterized version of the Korf function for Norway spruce (Piceo abies (L.) Karst.), Scots pine (Pinus sylvestris L.) and silver birch (Betula pe...Background: Generalized height-diameter curves based on a re-parameterized version of the Korf function for Norway spruce (Piceo abies (L.) Karst.), Scots pine (Pinus sylvestris L.) and silver birch (Betula pendula Roth) in Norwa are presented. The Norwegian National Forest Inventory (NFI) is used as data base for estimating the model parameters. The derived models are developed to enable spatially explicit and site sensitive tree height imputatio in forest inventories as well as future tree height predictions in growth and yield scenario simulations. Methods: Generalized additive mixed models (gamm) are employed to detect and quantify potentially non-linear effects of predictor variables. In doing so the quadratic mean diameter serves as longitudinal covariate since stand ag as measured in the NFI, shows only a weak correlation with a stands developmental status in Norwegian forests. Additionally the models can be locally calibrated by predicting random effects if measured height-diameter pairs are available. Based on the model selection of non-constraint models, shape constraint additive models (scare) were fit tc incorporate expert knowledge and intrinsic relationships by enforcing certain effect patterns like monotonicity. Results: Model comparisons demonstrate that the shape constraints lead to only marginal differences in statistical characteristics but ensure reasonable model predictions. Under constant constraints the developed models predict increasing tree heights with decreasing altitude, increasing soil depth and increasing competition pressure of a tree. / two-dimensional spatially structured effect of UTM-coordinates accounts for the potential effects of large scale spatial correlated covariates, which were not at our disposal. The main result of modelling the spatially structured effect is lower tree height prediction for coastal sites and with increasing latitude. The quadratic mean diameter affects both the level and the slope of the height-diameter curve and both effects are positive. Conclusions: In this investigation it is assumed that model effects in additive modelling of height-diameter curves which are unfeasible and too wiggly from an expert point of view are a result of quantitatively or qualitatively limited data bases. However, this problem can be regarded not to be specific to our investigation but more general since growth and yield data that are balanced over the whole data range with respect to all combinations of predictor variables are exceptional cases. Hence, scare may provide methodological improvements in several applications by combining the flexibility of additive models with expert knowledge.展开更多
基金Sponsored by Innovation Strategy Research Project of Fujian Provincial Department of Science and Technology(2023R0068)“East Fujian Tourism Poverty Alleviation Research Center”Project of Humanities and Social Sciences Research Base of Fujian Provincial Department of Education(Minjiaoke[2019]32)Survey and Research on the Construction Resources of Beautiful Countryside in East Fujian under the Guidance of“the Spirit of the 20th National Congress of the Communist Party of China”at Ningde Normal University(2022DZX08)。
文摘Based on the analysis on the current situation of marine fishery resources and development in Ningde City,this paper plans a spatial pattern for the integration of marine fishery and tourism of the“one belt,three zones,and multiple points”,designs key projects,analyzes the existing problems in the integrated development of fishery and tourism,and proposes relevant countermeasures and suggestions.
基金financially supported by the National Natural Science Foundation of China(92062215,41720104009,42172069)the China Geological Survey(DD20221886,DD20221817,DD20221657,DD20230340,DD20221630)+1 种基金the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0201)the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0801)。
文摘The ultramafic massif of Feragen,which belongs to the eastern ophiolitic belt of Norway,has abundant amounts of chromite ores.Recent studies have revealed a complex melt evolution in a supra-subduction zone(SSZ)environment.This study presents new whole-rock major element,trace element,and platinum-group element chemistry to evaluate their petrogenesis and tectonic evolution.Harzburgites have high CaO,Al_(2)O_(3),TiO_(2),MgO,and REE contents corresponding to abyssal peridotites,whereas dunites have low CaO,Al_(2)O_(3),TiO_(2),MgO,and REE contents corresponding to SSZ peridotites.The Cr^(#)and TiO_(2) of chromian spinels in the harzburgites suggest as much as about 15%–20%melting and the dunites are more depleted with>40%melting.The harzburgites and the dunites and high-Cr chromitites represent,respectively,the products of low-degree partial melting in a back-arc setting,and the products of melt-rock interaction in a SSZ environment.The calculated fO_(2) values for dunites and high-Cr chromitites(-0.17–+0.23 and+2.78–+5.65,respectively and generally above the FMQ buffer)are also consistent with the interaction between back-arc ophiolites with oxidized boninitic melts in a SSZ setting.
文摘This study was conducted to provide a preliminary assessment of the sea cucumber fishery in Aurora, Philippines. This was conducted from February to June 2013. All sea cucumber gatherers and traders, obtained through snowball sampling, in each identified sea cucumber fishery area in six coastal municipalities (Baler, Dipaculao, Dinalungan, Casiguran, Dilasag and Dingalan) were interviewed using a structured interview schedule and focused group discussions (FGD). Results revealed that gathering sea cucumbers were accomplished by handpicking, skin diving or compressor diving. A total of 15 commercial species were regularly gathered. Out of this, three species are of very high economic value (≥Php 4000/kg) (Holothuria nobilis, Holothuria scabra, and Actinopyga lecanora). The average number of kilograms harvested per hour per trip ranges from 0.21 (Holothuria fuscopunctata) to 2.71 (Holothuria scabra), while the average size of commonly gathered sea cucumber varies among species with Holothuria lecanora showed an average length (29.26 cm) greater than recorded 24 cm. Processing mainly involves washing, slicing, boiling, drying and packing. Processed sea cucumbers or trepan were sold to middlemen or direct buyers who usually offered higher prices (36.36% up to 69.20%) than the former. Problems encountered by sea cucumber gatherers and traders include a decline in total catch, a shift in area of collection from intertidal zones to deeper waters, an increase in the number of hours spent in finding and gathering sea cucumbers, the use of compressors in gathering, the decline of larger species and gathering of smaller sizes in huge amount, the absence of conservation program for sea cucumber, and the lenient implementation of government policies with regards to coastal resources management.
基金Special Funds for Basic Research and Operating Expenses of Central Nonprofit Research Institutes(2011JBFC04)Special Research Project of Public Service Sectors(agriculture)(200903048-03)Special Finance of Department of Agriculture(6125005)~~
文摘[Objective] The paper was scientifically evaluate the potential fishery productivity of Lihu using GIS technology.[Method] The evaluation of potential fishery productivity in Lihu was based on GIS and AHP according to the characteristics of fisheries resources in Lihu Lake.The evaluation system included 3 sub-models including water quality,biodiversity and hydrological condition,which totally had 10 indexes.Judgment matrix was constructed based the advices of professors of fisheries resources,and the indicator’s weight were calculated by the process of AHP.The ranking distributing map of potential fishery productivity in Lihu was obtained by the model of raster analysis,raster calculator,spatial overlay and classification models of ARC/INFO.[Result] Potential fishery productivity of Lihu was divided into 4 grades in term of higher,high,general and low,and which covered 2.643 3,3.844 8,1.121 4 and 0.400 5 hm2,respectively.[Conclusion] The study provided theoretical basis for ecological reconstruction of Lihu Lake.
基金supported by the National Bulk Freshwater Fish Industry Technology System(CARS-45-33)Tianjin Freshwater Aquaculture Industry Technology System Innovation Team(ITTFRS20211000-005/002)+2 种基金Tianjin Science and Technology Plan Project(23YDTPJC00420)Central Guiding Local Science and Technology Development Fund(24ZYCGSN00250)Open Fund of Key Laboratory of Environmental Standards and Environmental Pollution of the Ministry of Education(202007,202105).
文摘According to the"National Modern Facility Agriculture Construction Plan(2023-2030)released by the Ministry of Agriculture and Rural Affairs,the"Special Implementation Plan for Modern Facility Fisheries Construction"emphasizes the development of circular aquaculture,active expansion of green aquaculture space in facility fisheries,multi-channel development of food sources,comprehensive improvement of the quality,efficiency,and competitiveness of facility fisheries,ensuring stable and safe supply of aquatic products,and better meeting people's needs for high-quality aquatic products and beautiful aquatic ecological environment.Since the implementation of the 14th Five Year Plan for fisheries,facility fisheries have made significant progress.In order to thoroughly implement General Secretary Xi Jinping's important discourse on new quality productivity,conduct in-depth research on the current situation and existing problems of the fishery industry,and put forward suggestions to meet the requirements of high-quality development of the fishery industry in the new era.Therefore,it is crucial to continue practicing the"revitalization of aquatic seed industry"and"big food concept",take multiple measures to"demand food from rivers,lakes,and seas",and expand aquaculture space.Through research,it has been found that research in the field of facility based fisheries is still in its developmental stage.Further exploration is needed on the current status,breeding models,and experimental demonstrations of land-based facility based fisheries,in order to provide a basis for fisheries regulatory authorities to formulate the"15th Five Year Plan"for facility based fisheries.
基金Phased Achievement of the Subside Project "Studies on Classification of Recreational Fishery Resources and Evaluation on its Development" of Chinese Marine Research and Development Center in2008(Grant no.AOCQN200816)
文摘Recreational fishery is the combination of traditional fishery and modern leisure activities.Development of recreational fishery resources must be based on related resources,but the present research on recreational fishery is mainly confined to the development of leisure projects,the definition of connotation and scope of recreational fishery resources is rather vague,and there is no precise classification and evaluation system.According to the resources attributes,resources functions,and tourism resources classification,investigation and evaluation standard,recreational fishery resources include a number of different types.Expert Scoring Method and Analytic Hierarchy Process can be used to determine the evaluation factors of recreational fishery resources and their weights,and then make comprehensive evaluation on recreational fishery resources of different regions and types,so as to improve the scientific nature of recreational fishery development.
文摘In 2011,China put the stock enhancement fishery in the same place as aquaculture,fishing,aquatic product processing and circulation industry,and recreational fishery,i. e. one of the five pillar industries of fishery economy. Developing the stock enhancement fishery is a strategic measure for restoring and protecting fishery resources,expanding fishery,replacement environment cost,and promoting sustainable development of fishery. At present,cultivation and development of the new rising industry,the stock enhancement fishery,has certain comparative edge,excellent economic foundation and broad development space in China.
文摘In Cambodia,fishery co-management is an important process to transfer authority and ownership to the communities along the Tonle Sap Lake to manage fishery.This paper aims to determine why the co-management of small-scale fishery has not been implemented satisfactorily in the Tonle Sap Lake of Cambodia.The research was primarily based on a household survey among 404 house-holds for quantitative data,equally divided between the Cham(202 households)and Khmer(202 households).Participatory process was also applied to collect qualitative data from key stake-holders.We found that limited interaction among the involved stakeholders,i.e.,unequal distribution of authority and resources co-management,has impeded implementation.The engagement of fisherfolk was influenced by dependence on fishery,law enforcement,and events organized by the communities.While the Khmer had better opportunities to participate in planning at the provincial and district levels,the Cham were only engaged in local development activities initiated by their people.However,the latter evinced a higher rate of satisfaction due to their access tofishery resources and to a large quantity of fishing gear.In the future,efforts should be made to:(1)improve resource and authority sharing among all key stakeholders;(2)urgently resolve issues pertinent to capacity building,insufficient budgets for commune councils(CoCs)and community fishery(CFi);and(3)urge law enforcement regarding illegal fishing.
文摘This article studies the inshore-offshore fishery model with impulsive diffusion. The existence and global asymptotic stability of both the trivial periodic solution and the positive periodic solution are obtained. The complexity of this system is also analyzed. Moreover, the optimal harvesting policy are given for the inshore subpopulation, which includes the maximum sustainable yield and the corresponding harvesting effort.
基金This research was partially supported by the National Hi-technology Program of China under contract No.2001AA633010,No.2001AA639080 and No.2002AA639460.
文摘The ocean fishery and the corresponding environment are highly interrelated according tothe production experiences of ocean fishing population. The spatial cluster patterns are constructed using the remote sensed data and long-time series fishery production data under the uniform coordinate based on GIS techniques. Thus, the hidden information of distribution regularities between ocean-hydrologic factors and central fishing ground can be extracted from these patterns. It is important to forecast the ocean fishery production.
基金Supported by the Program for New Century Excellent Talents in University (No.NCET-06-0437)the National High Technology Research and Development Program of China (863 Program) (No.2007AA092201+2 种基金2007AA092202)Shanghai Leading Academic Discipline Project (No.S30702)Doctorship Fund of Shanghai Ocean University (No.06-326)
文摘Generalized linear models (GLM) and generalized additive models (GAM) were used to standardize catch per unit fishing effort (CPUE) of Ommastrephes bartramii for Chinese squid-jigging fishery in Northwest Pacific Ocean. Three groups of variables were considered in the standardization: spatial variables (longitude and latitude), temporal variables (year and month) and environmental variables, including sea surface temperature (SST), sea surface salinity (SSS) and sea level height (SLH). CPUE was treated as the dependent variable and its error distribution was assumed to be log-normal in each model. The model selections of GLM and GAM were based on the finite sample-corrected Akaike information criterion (AICC) and pseudo-coefficient (Pcf) combined P-value, respectively. Both GAM and GLM analysis showed that the month was the most important variable affecting CPUE and could explain 21.3% of variability in CPUE while other variables only explained 8.66%. The interaction of spatial and temporal variables weakly influenced the CPUE. Moreover, spatio-temporal factors may be more important in influencing the CPUE of this squid than environmental variables. The standardized and nominal CPUEs were similar and had the same trends in spatio-temporal distribution, but the standardized CPUE values tended to be smaller than the nominal CPUE. The CPUE tended to have much higher monthly variation than annual variations and their values increased with month. The CPUE became higher with increasing latitude-high CPUE usually occurred in 145°E-148°E and 149°E-162°E. The CPUE was higher when SST was 14-21℃ and the SLH from -22 cm to -18 cm. In this study, GAM tended to be more suitable than GLM in analysis of CPUE.
基金European UnionAward Number 281116ERA02S+9 种基金Recipient:Hans PretzschProject Title:“Management of mixedspecies stands.Options for a low-risk forest management(REFORM)”Bayerisches Staatsministerium fur Ernahrung,Landwirtschaft und Forsten (Bavarian State Ministry for Nutrition,Agriculture,and Forestry)Award Number W07 7831–22209-2013Recipient:Hans PretzschProject Title:“Long-term experimental plots for forest growth and yield research”Deutsche Forschungsgemeinschaft (German Science Foundation)Award Number PR 292/12–1Recipient:Hans PretzschProject Title:“Tree and stand-level growth reactions on drought in mixed versus pure forests of Norway spruce and European beech”
文摘Background: Climate change triggered many studies showing that trends and events of environmental conditions can reduce but also accelerate growth at the stand and individual tree level. However, it is still rather unknown how climate change modifies the growth partitioning between the trees in forest stands.Methods: Based on long-term girth-tape measurements in mature monospecific and mixed-species stands of Norway spruce(Picea abies(L.) Karst.) and European beech(Fagus sylvatica L.) we traced the effect of the severe droughts in 2003 and 2015 from the stand down to the tree level.Results: Stand growth of Norway spruce decreased by about 30% in the once-in-a-century drought 2015, while European beech was much more drought resistant. Water availability generally amplified size-asymmetric growth partitioning. Especially in case of Norway spruce water availability primarily fostered the growth of predominant trees, whereas drought favoured the growth of small trees at the expense of the predominant ones. We could not detect significant differences between mixed and monospecific stands in this regard.Conclusions: The drought-induced reallocation of growth in favour of small trees in case of spruce may result from its isohydric character. We hypothesize that as small trees are shaded, they can benefit from the reduced water consumption of their sun-exposed taller neighbours. In case of beech, as an anisohydric species, tall trees suffer less and smaller trees benefit less under drought. The discussion elaborates the consequences of the water dependent growth allocation for forest monitoring, growth modelling, and silviculture.
文摘Na-metasomatism in the form of albitisation is regionally extensive in the Precambrian crust of southern Scandinavia and is particularly widespread in the Bamble Sector, the Kongsberg-Modum Sector and the Norwegian part of the Mylonite Zone. Sites of albitisation outside these belts are associated with hy- drothermal breccia pipes and fracture-bound alteration. The albitites are composed of near end-member sodic plagioclase (Ano 5Ab94-99) with minor carbonate (calcite and dolomite), rutile, clinopyroxene (En30Fs21-23W047 49), amphibole (edenite-pargasite), quartz, titanite, tourmaline, epidote (Fe3+ - 0.20 -0.85 a.p.f.u) and chlorite (Mg# = 0.81-0.89). The albitites have been studied in detail in the region around the town of Kragem, and are described as albitisation along veins, as breccias, alhitic felsites, massive carbonate-bearing albitites and megascale clinopyroxene-titanite-bearing albitite. The strong fluid control on their formation is illustrated by the veining and mineral replacement reactions, showing fluid transport by a H20-CO2 fluid rich in Na, depleting Fe and Mg from the host rock, in accordance with calculated mass transfer. A study of the mineralogical replacement reactions in combination with a regional compilation has demonstrated the relationship between metasomatic processes and the for- mation of apatite, ruti|e and Fe deposits. The albitites occur spatially associated with other metasomatic rocks such as scapolitised metagabbros. We document that metasomatism is an important mineral- and rock-forming process in the continental crust, which in the Bamble Sector is a part of the tectonome- tamorphic evolution of the Sveconorwegian orogen.
文摘Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh) can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d) models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM) and shape constrained generalized additive models (SCAM) for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand, The definition of constraints leads only to marginal or minor decline in the model statistics like AIC An observed structured spatial trend in tree height is modelled via 2-dimensional surface fitting. Conclusions: We demonstrate that the SCAM approach allows optimal regression modelling flexibility similar to the standard GAM but with the additional possibility of defining specific constraints for the model effects. The longitudinal character of the model allows for tree height imputation for the current status of forests but also for future tree height prediction.
基金The National Natural Science Foundation of China(41106094)the Fundamental Research Funds for the Central Universities(DUT14RC(3)112)
文摘Jellyfish fishing is a special type of fishery that mainly exists in some countries of East and Southeast Asia. China has the largest jellyfish fishery yield in the world with an annual harvest of around 300 thousand tons. Liaodong Bay is the most important jellyfish fishery ground in China. However, due to the high benefits of jellyfish fishery, which leads to illegal and out-of-season jellyfish fishing occurring each year in Liaodong Bay. Illegal jellyfish fishery in Liaodong Bay is a typical example of the tragedy of the commons. The key problem is that fishermen seek to an illegally initiate jellyfish fishing as early as possible. In this paper, basing on the data of edible jellyfish's biology and ecology, we mainly analyzed the history of jellyfish fishery in China, especially in Liaodong bay, and then we calculated the carry capacity of edible jellyfish in Liaodong Bay which is about 300 thousand tons one year. This number is equal to the recent annual yield of edible jellyfish in China. Furthermore, basing on the carry capacity and reasonable quotas price analysis, we set up a Jellyfish fishing quotas and deficit quotas buyback system which could be a suitable and effective solution for jellyfish fishery management and development in Liaodong Bay at the underlying roots. Although China is the first country with edible jellyfish aquaculture, the annual yield of jellyfish aquaculture is only one fifth of jellyfish fishing. So, there is a very bright developing prospect about edible jellyfish aquaculture in China.
文摘[Objective] The aim was to make a comprehensive evaluation and explore strategies on fishery development. [Method] Fishery development in China was analyzed and concerning evaluation system was established based on its development stage, international competiveness and exportation. In addition, a comprehensive evaluation was made on fishery and countermeasures were proposed considering from government, department of quality control, fishery guild, producing and processing enterprises. [Result] Although progresses have been made in fishery in China, some problems still exist, such as overdose of drug residues, overloading breeding, lower additional value of products, and fewer excellent and famous products. Hence, local governments should give much support to fishery and enhance competitiveness to improve the products in global market; departments of quality control should strengthen supervision and management on fishery products against technical trade barriers; fishery guilds or researching institutions should provide technical support for concerning breeding and processing which should be mainly relied on science and technology. [Conclusion] The research provided references for fishery development.
文摘Artificial fish nests are set in Lukou section and Hengyang section of Xiangjiang River from March 20 to May 10, 2019. The structure of artificial fish nest is bamboo frame, with the size of 2.5 m × 5.0 m × 4 and a unit frame area of 60 m<sup>2</sup>. A total of 58,201 eggs were collected by 24 monitoring times, of which 30,441 were from Lukou and 27,760 from Hengyang. 3831 fish eggs identify 8 fish species using morphological or molecular biological methods. The results showed that the number of eggs peaked from the 8<sup>th</sup> day to the 24<sup>th</sup> day after the nest entered the water, and then decreased rapidly. There was significant negative correlation between egg number in per m<sup>2</sup> fish nest and days of fish nest (P < 0.01). The economic benefits of artificial fish nests were RMB 11.81 million. The artificial fish nest can not only increase the population of fish, but also has significant economic benefits.
基金This study is supported by the project from the Food and Agriculture Organization of the United Nations(FAO)(No.GF.FIRFD.RA20403020400).
文摘Surplus production models(SPMs)are among the simplest and most widely used fishery stock assessment models.The catch-effort data analysis(CEDA)and a surplus production model incorporating covariates(ASPIC)are softwares for analyzing fishery catch and fishing effort data using nonequilibrium SPMs.In China Fishery Statistical Yearbook,annual fishery production and fishing effort data of the Yellow Sea,Bohai Sea,East China Sea,and South China Sea have been published from 1979 till present.Using its catch and fishing effort data from 1980 to 2018,we apply the CEDA and ASPIC to evaluate fishery resources in Chinese coastal waters.The results show that the total maximum sustainable yield(MSY)estimate of the four China seas is 10.05-10.83 million tons,approximately equal to the marine fishery catch(10.44 million tons)reported in 2018.It can be concluded that China’s coastal fishery resources are currently fully exploited and must be protected with a precautionary approach.Both softwares produced similar results;however,the CEDA had a much higher R2 value(above 0.9)than ASPIC(about 0.2),indicating that CEDA can better fit the data and therefore is more suitable for analyzing the fishery resources in the coastal waters of China.
基金supported by the Norwegian Institute of Bioeconomy Research(NIBIO)
文摘Background: Generalized height-diameter curves based on a re-parameterized version of the Korf function for Norway spruce (Piceo abies (L.) Karst.), Scots pine (Pinus sylvestris L.) and silver birch (Betula pendula Roth) in Norwa are presented. The Norwegian National Forest Inventory (NFI) is used as data base for estimating the model parameters. The derived models are developed to enable spatially explicit and site sensitive tree height imputatio in forest inventories as well as future tree height predictions in growth and yield scenario simulations. Methods: Generalized additive mixed models (gamm) are employed to detect and quantify potentially non-linear effects of predictor variables. In doing so the quadratic mean diameter serves as longitudinal covariate since stand ag as measured in the NFI, shows only a weak correlation with a stands developmental status in Norwegian forests. Additionally the models can be locally calibrated by predicting random effects if measured height-diameter pairs are available. Based on the model selection of non-constraint models, shape constraint additive models (scare) were fit tc incorporate expert knowledge and intrinsic relationships by enforcing certain effect patterns like monotonicity. Results: Model comparisons demonstrate that the shape constraints lead to only marginal differences in statistical characteristics but ensure reasonable model predictions. Under constant constraints the developed models predict increasing tree heights with decreasing altitude, increasing soil depth and increasing competition pressure of a tree. / two-dimensional spatially structured effect of UTM-coordinates accounts for the potential effects of large scale spatial correlated covariates, which were not at our disposal. The main result of modelling the spatially structured effect is lower tree height prediction for coastal sites and with increasing latitude. The quadratic mean diameter affects both the level and the slope of the height-diameter curve and both effects are positive. Conclusions: In this investigation it is assumed that model effects in additive modelling of height-diameter curves which are unfeasible and too wiggly from an expert point of view are a result of quantitatively or qualitatively limited data bases. However, this problem can be regarded not to be specific to our investigation but more general since growth and yield data that are balanced over the whole data range with respect to all combinations of predictor variables are exceptional cases. Hence, scare may provide methodological improvements in several applications by combining the flexibility of additive models with expert knowledge.