Spatial analysis of the impact of shrimp culture on the coastal wetlands on the Northern coast of Sinaloa, Mexico

In the Mexican coasts, as in many tropical and subtropical coastal areas, shrimp culture grew exponentially over the last three decades. This process has produced an intense debate on the economic benefits but also about the extent and intensity of the impact of this activity on the coastal ecosystems, particularly the effects of pond construction on mangrove areas and other coastal wetlands. For the Northern coast of Sinaloa (Northwest Mexico), a region where shrimp culture is actively practiced and reproduces most of the shrimp controlled production model in Mexico, a land cover change-detection analysis, with Landsat images, outputs that 75% of the shrimp farming in this region has been built on saltmarshes while less than 1% was constructed on mangrove areas. Through the estimation of landscape metrics for different scenarios (with and without shrimp culture infrastructure), we find that in addition to direct removal of saltmarshes, shrimp aquaculture has significantly modified the spatial patterns of coastal wetlands, retreating wetland borders and fragmenting their patches. These last impacts are mainly related with the development of the linear infrastructure associated with shrimp culture (drainage channels and roads), rather than the construction of the ponds. Present findings and other from similar studies done in Northwest Mexico; allow us to estimate that 60% of shrimp farming in Mexico impacted directly on saltmarshes, contrasting with the 3% of shrimp farms built on mangroves.     

闽南沿海地区海岸带韧性时空分布特征

在全球气候变化和人类活动的双重胁迫下,人口密度高、经济发达的沿海地带成为生态环境风险的高危地区。为揭示研究区海岸带韧性特性,有效评价海岸带韧性发展历程,从而对海岸带韧性提升提出针对性成效管理策略。本研究以闽南沿海地区的18个县区（不包括金门县）为研究对象,选取海岸动力、海岸防护能力、经济发展、社会发展以及生态特征等5个方面、14个海岸韧性指标因子,利用AHP Critic法、灰色关联TOPSIS法、自然断点法以及贡献度模型,构建研究区海岸带韧性评价体系。结果表明,闽南沿海地区在空间上呈现出中部以厦门市辖区为代表区域的海岸带韧性高值区（韧性平均值为0.517~0.542）,南部是漳州沿海地区的海岸带韧性低值区（韧性平均值为0.482~0.514）;海岸动力、海岸防护能力是其主控要素和影响因子。闽南沿海地区韧性演化经历了3个阶段,分别是早期的韧性提升阶段（1980—1990年）,经济高速发展中生态环境造破坏的韧性破坏阶段（1991—2010年）,注重生态修复保护工作,使海岸带韧性提升的恢复阶段（2011—2020年）。厦门、漳州、泉州三地在上述3阶段的韧性演化过程存在时间上的相位差异,其与三地不同的区位特点与地域经济发展历程有关。     

Technical, economics and environmental analysis of semi-intensive shrimp (Litopenaeus vannamei) farming in Sonora, Sinaloa and Nayarit states, at the east coast of the Gulf of California, México

In Mexico shrimp pond aquaculture is the main activity and contributes with 45.9% of the total fisheries volume and 74.3% of gross profit generated by the national products, being Sonora, Sinaloa and Nayarit in the east coast of the Gulf of California the states generating around 70% of region gross profit. The main species cultivated is the white shrimp Litopenaeus vannamei, and for this reason academic and government sector devoted much attention in this species, however, still researching on economic feasibility is scarce and needed. In this paper, the technical, economics, production and environment parameters of 80 semi-intensive commercial in these states are analyzed and discussed. The results showed the main external constraints affecting short and long run farm performance. The overall observations pointed out that there is an increase on yield and income when shrimp farms invest in higher quality inputs such as equipment and technology for more efficiency in using water, use of certified post-larvae and better design of farm facility. Nevertheless, further research is needed to adjust shrimp production strategies to specific farm requirement by investing in premium quality inputs. Furthermore, the most serious threat from shrimp aquaculture is the potential effect on water quality and the infrastructure associated, that having more serious effects on the environment, particularly in the coastal wetlands. The economic and the environment care must be driven to lead a more sustainable scenario.     

Integrated coastal zone management using the ecosystems approach,some perspectives in Malaysia

An effective assessment of functions, goods and services of coastal ecosystems requires commitment from the various stakeholders and an integrated approach in the management of the ecosystem. Malaysia has made commitments through its policies, the latest being the Eighth Malaysia Plan, for 2001–2005 (“8th MP”), which is the first phase implementation of the Third Outline Perspective Plan (“OPP3”), charting the development of the nation for the first decade in the 21st Century. The pledge to develop an Integrated Coastal Zone Management Policy (“ICZM”) is being carried out to reconcile conflicting uses and ensure sustainability of coastal resources, plus identify and provide for uniformity and minimum standards to be adopted in Malaysia. These policy instruments (e.g. OPP3, 8th MP, Draft ICZM, National Policy on Biodiversity) will set the objectives and direction that will allow for formal instruments of implementation of strategies and plans envisaged to take place, besides setting the stage for the various stakeholders and outlining responsibilities and commitments. It will also allow for disciplines and findings be it in science, socio-economic and humanities to interface with policies and its instruments of implementation, especially when put into the context of the ecosystems approach.     

Integrated coastal zone management in the Patos Lagoon estuary: perspectives in context of developing country

Located at the southern Brazilian coast, the Patos Lagoon estuary is bordered by the cities of São José do Norte and Rio Grande, which depend on a series of economic sectors associated with the nearby presence of the estuary and ocean, such as estuarine shrimp fisheries, small-scale ocean fisheries, tourism, port activities and associated industrial activities. Despite its environmental and socioeconomic importance, the Patos Lagoon estuary has suffered severe environmental disturbances mainly over the last three decades. This ongoing trend makes it a priority to develop an Integrated Coastal Management Plan for this area. Recent studies have demonstrated the environmental degradation of several coastal habitats, such as dunes, embayments and salt marshes. Most fisheries have experienced a marked decline, leading to a serious social crisis that has affected approximately 50,000 people directly or indirectly involved in the traditional activity. The growing poverty of small farmers and fishermen has placed increasing demands on local governments, which are struggling to manage conflicts between traditional and non-traditional sectors. This paper describes the objectives, criterions and expected results of an initiative for an ICZM program to be implemented in the estuary, as well as the main difficulties in a context of developing country.     

青岛市海岸带地质环境问题与空间规划对策建议

充分认识海岸带地质环境问题关系到所有沿海城市居民的生命财产安全,对于优化城市规划布局和国土空间开发,实现空间转型升级和城市集约、绿色、可持续发展具有重要意义。青岛市是中国沿海重要中心城市,正在全力建设全球知名的海湾都会,同时,当前也面临一定程度的地质环境问题。本文系统分析了青岛市海岸带地区地质灾害（崩塌、滑坡、泥石流等）、不良地质条件、海（咸）水入侵、海岸侵蚀、构造断裂、水土污染等地质环境问题的现状及其分布特征和产生原因,并针对国土空间优化、韧性城市建设、生态城市建设、智慧城市建设和相关规制、法律体系构建等方面提出了对策建议,为城市科学规范空间规划提供参考,为地区经济与社会可持续发展提供系统科学的地质资料。     

Impacts of shrimp farming in Bangladesh: Challenges and alternatives

Shrimp farming is growing in Bangladesh due to suitable agro-climatic conditions, adequate water resources, cheap labour force, international donor agencies and the involvement of multinational corporations. Although it provides immediate economic benefits, contributes to poverty reduction and food security, as well as generates employment from seed collectors to exporters, it has also been facing a host of challenges. They hinder the sustainable development of this otherwise thriving sector. This paper aims to expound the hindrances and challenges for sustainable shrimp farming in Bangladesh by means of reviewing the available scientific literature. It finds that socioeconomic impacts such as traditional livelihood displacement, social unrests and market fluctuations are hindering the sustainable development of shrimp farming in Bangladesh. Similarly, environmental impacts such as mangrove degradation, salt water intrusion, sedimentation, pollution and disease outbreaks are found to be obstacles for the development of sustainable shrimp farming. Inappropriate management practices and inadequate plans regarding water quality, seed supply, irrigation facilities and fishery resources, added to institutional weaknesses, jeopardize the future growth of shrimp farming. Therefore, this paper shall provide substantial input to set the directions that research for alternatives can take and that can contribute to the sustainability of shrimp farming.     

Feeding intensity and molecular prey identification of the mantis shrimp,Oratosquilla oratoria (De Haan, 1844), in the Tianjin coastal zone of Bohai Bay

Bohai Bay, a representative semi-enclosed bay of China, has been severely impacted in recent decades by rapid human development. Although the mantis shrimp Oratosquilla oratoria plays an important role in the Bohai Bay ecosystem and fishery, its feeding ecology and the impact of habitat changes on its feeding habits are poorly known. In this study, we sought to identify its feeding strategy through the separation of stomach contents, and to describe its trophic ecology during maturation in the Tianjin coastal zone of Bohai Bay by the DNA barcoding method using a fragment (about 690 bp) of the mitochondrial cytochrome oxidase I (CO I) gene. A total of 594 specimens were collected from March to July 2018, and 347 (58.42%) stomachs were found to have food remains. More than half of the O. oratoria individuals had poor feeding activity, and the degree of feeding of females was higher than that of males, but there was no significant difference in the visual fullness index and the fullness weight index (FWI) between sexes for each month. In addition, the feeding activity of O. oratoria was consistent across the months, suggesting in artificial breeding programs it is not worried too much about the accessional diet supplied to the female bloodstocks except maintaining their normal food. A total of 167 retrieved prey items yielded 187 readable sequences; 86.63% of these sequences could be assigned to the species level. Consequently, 25 different prey taxa covering all readable sequences were identified, showing O. oratoria is a generalist predator. In terms of percent composition by frequency of occurrences (%N), crustaceans and fishes accounted for the same and highest percentage (35.83%) in the mantis shrimp diet, followed by mollusks (24.59%) and the remaining marine organisms (3.73%) including Polychaeta (2.67%), Sagittoidea (0.53%), and Chromadorea (0.53%). The result shows the benthic fish Oxudercidae (family) appears to be an especially important food supply for O. oratoria during maturation. The degree of cannibalism decreased with an increase in diet species and the frequencies of cannibalism in this study was noticeably higher than that in previous studies, suggesting that cannibalism may be a significant feeding strategy in the mantis shrimp O. oratoria in the Tianjin coastal zone of Bohai Bay, and because of the frequently cannibalistic behavior, the high stocking density of broodstocks should be avoided.     

海岸带滨水区环境胁迫与利用策略研究

海岸带滨水区具有多重功能,是地球上物理、化学、生物和地质过程最活跃的地区,对人类社会发展具有特别重要的意义.但随着海洋城市建设的加速推进,海岸带资源开发力度的不断加大,滨水区承受的压力也日益加剧.本文归纳总结了海岸带滨水区开发利用方式及特点,系统地分析了滨水区环境退化的胁迫机理,研究提出了海岸带滨水资源利用的六方面策略:1)以循环经济和可持续发展理念指导海岸带滨水区的开发利用;2)对滨水区生产和生活岸线布局进行战略调整;3)坚持亲水性原则,精心布局,开发好、利用好海湾滨水资源;4)大力发展海岸带滨水区沙滩特色旅游,高度重视沙滩的保护;5)构建海岸带滨水区生态预警与防范体系;6)实施海岸带滨水区生态修复、加强海湾滨岸生态化建设.     

山东半岛近岸海带养殖活动对水体光学吸收特性的影响

为了研究近岸海带养殖活动对水体光学特性的影响,本文选取山东半岛黑泥湾海域为典型研究区,利用2021年4月和8月在该区的9站同步观测数据,分析其总悬浮颗粒物、藻类颗粒物、非藻类颗粒物以及有色溶解有机物的吸收特性,并计算各组分对总吸收系数的贡献率,同时采用Quasi-analytical algorithm (QAA)算法借助MODIS影像反演了水体总吸收系数,结合实测数据获得了黑泥湾水体吸收特性的季节变化情况。结果表明,有海带养殖季节表层水体藻类颗粒物、非藻类颗粒物、总颗粒物和有色溶解有机物的吸收系数明显大于无海带养殖季节,且春季海带养殖区水体的总吸收系数大于无海带养殖区;海底表层沉积物的再悬浮造成底层吸收系数较大,而在春季成熟期的海带汇聚较大量的有机物质导致中层藻类颗粒物吸收系数相对较高;参考波长向红波移动,QAA_v5算法能够较好地估算该区表层水体吸收系数,且在海带养殖季节水体组分会影响到更长的波段特征。本研究可为深入了解海带养殖对水体各组分浓度和分布、碳循环以及水生生态系统的结构和功能的影响提供参照,并有助于提高近岸水体组分的遥感反演精度。     

Community structure of macrobenthos in coastal water off Rushan, southern Shandong Peninsula, and the relationships with environmental factors

To understand the present actuality of the marine ecosystem in the southern coastal water region of the Shandong Peninsula and the impact of the global change and the human activities to the marine ecosystem of the region,the macrobenthic community structure was researched based on data from 26 sampling stations carried out on four seasonal cruises from December 2006 to November 2007.The data was analyzed using PRIMER 6.0 and SPSS 15.0 software packages.The results showed that 236 macrobenthic species in total were collected from the research region by the field works.Most of the species belong to Polychaeta (76 species),Mollusca (75) and Crustacea (60).Of which,33 species were common species by the four cruises.The dominant species were different among the four seasons,however,the polychaete species Nephtys oligobranchia and Sternaspis scutata were always dominant in the four seasons.The abundances and biomasses of the macrobenthos from the research region were variable in the four seasons.The results of CLUSTER and MDS analysis showed that the similarities of macrobenthic structures among the stations were low,most of the similarities were at about 40% of similarity values,only that of two stations were up to 60%.In accordance with the similarity values of the macrobenthic structures,the 26 stations were clustered as six groups at arbitrary similarity level of 30%.The ABC curve indicated that the marcofauna communities in the research region had not been disturbed distinctly.The results of BIOENV and BVSTEP (Spearman) analysis implied that the concentrations of organic matter in bottom water and heavy metal copper in sediment,water depth and temperature of bottom were the most significant environmental factors to affect the macrobentic community.     

对虾封闭式工厂化养殖水环境要素的变化特征及其相互关系

根据2002年8月7～8日对虾工厂化养成中后期A、B代表池的实测数据，分析讨论了该时期养殖水体中环境要素的变化特征及其相互关系．结果表明：研究水体水温、盐度和溶解氧含量适宜．日变化幅度不大．但pH值略为偏低，而COD值明显偏高．与该时期投饵量大，残饵及排泄物明显增加有关．但对A池来说，生物作用的影响占主导地位，而对B池而言．则以化学过程影响为主．     

福建南部沿海的江豚

在闽南厦门至漳浦沿海获22只江豚,根据背部棘状小结节的数量与分布,可明显分为两个亚种,即指名亚种(N.P.Phocaenoides,81%)和北方亚种(N.P.Sunameri,19%),表明本海域是几个亚种的混栖地带,分析了这些江豚的外部形态和种群结构,测定了脂肪层及各内脏的重量.     

A model-based approach to unravelling naval defence heritage: supply- and demand-side issues in Portsmouth's coastal zone

The paper explores the nebulous concept of heritage in order to highlight issues relevant to the revitalisation and management of historic naval waterfronts. A model separating supply and demand sides, and further subdividing each side into political, social and economic structures, is used as a framework for analysis. The whole is set within a perceptual filter, and interpretation is subsumed within social structure. The model is applied to heritage concepts at Portsmouth Dockyard and to the legacy of naval defence in the neighbouring coastal zone. From the review of all three structures it is shown that economic considerations are increasingly powerful on both the supply and demand sides, as sovereignity passes to customers who are less interested in authenticity and architectural quality than in securing value for money. Issues and implications arising from this trend, and relevant to naval heritage planning and management, are identified.     

Wind waves in the coastal zone of the southern crimea: Assessment of simulation quality based on in situ measurements

The study verifies the Black Sea wave model using field data obtained from the Katsiveli research platform. The WAM and mesoscale MM5 and WRF atmospheric models, which are used to calculate the wind field for the wave model, were recently adjusted to the Black Sea region at the Marine Hydrophysical Institute. The results of the work are presented as characteristics of the simulation quality used in world practice in other regions. The scatter index for a significant wave height is 70% in summer and 50% in winter. The values of the scatter index of wave parameters and wind speed appear to be at the same level as in semi-enclosed seas on the northern side of the Mediterranean Sea. It is shown that atmospheric simulation correctly reproduces the interaction between synoptic processes and the mountain range extending alongshore. Error sources in wave simulation are discussed. The most significant drawback is the possibility of mesoscale instability in the atmospheric model without assimilation of observation data within the computational domain.     

海岸带土地发展潜力评价——以杭州湾南岸为例

土地潜力评价是编制土地利用规划的前提,把握土地的潜在经济效能是城镇化、工业化快速推进背景下土地资源合理配置的重要命题。本文甄选自然条件、生态敏感性、经济发展和空间结构指标建立了土地发展潜力评价体系,分别采用模糊综合评价法与网络层次分析法赋权指标体系与计算权重,测度发展潜力值并划分了杭州湾南岸余姚、慈溪和镇海的海岸带土地发展潜力区。结果显示:(1)低发展潜力区面积为237.14 km²,占比为17.73%;中发展潜力区面积为323.08 km²,占比为24.15%;高发展潜力区面积为473.34 km²,占比为35.38%;极高发展潜力区面积为304.27 km²,比例为22.74%。(2)按照地类的级别面积分析,交通运输用地和自然保留地面积在极高潜力区中达到峰值,呈由高向低等级面积递减态势;耕地、其他农用地、城乡建设用地和其他建设用地在高潜力区中占比最大,且基本布局于极高、高潜力区;园地、河流水面、水利建设用地集中于中潜力区,而沿海滩涂与林地基本分布于低、中潜力区。(3)余姚、慈溪和镇海海岸带土地发展潜力分区呈现不同特点,余姚属于待提升型,慈溪为均衡发展型,镇海是高质发展潜力型。     

福建省近岸海域环境因子分布特征及富营养化评价

本研究于2019年春、夏、秋季对福建省闽西南近岸海域海水营养盐和叶绿素a等环境因子进行调查采样,分析其时空分布特征,同时应用有机污染指数法和富营养化指数法2种评价方法对该海域海水富营养化水平进行评价对比,采用主成分分析法探讨环境因子对该海域富营养化状态的影响.结果显示,有机污染指数和富营养化指数的时空分布特征基本一致,...     

Situation of integrated coastal zone management in Central America: Experiences of the IUCN wetlands and coastal zone conservation program

Central American coastal zones possess extensive scenic and geographical wealth as well as great biological diversity. These coasts maintain 21.6% of the region’s population and produce at least US$ 750 million alone in fishing activities that provide work and sustenance for more than 450 000 persons in the region. Eight percent of the world’s mangroves are located in Central America, as well as the second largest corral reef barrier on the planet. A good representation of the region’s natural heritage is conserved in approximately 110 protected areas. Due to these special conditions, at least 50% of Central America’s coastal zones is devoted to tourism, one of the three primary economic activities in four of the region’s countries. Integrated coastal zone management (ICZM) in this region has been limited by information gaps, restricted technical and financial capacity, and strong sectoralism. Some recent projects, both governmental and supported by NGOs, offer new experience and lessons on regional ICZM. These initiatives have been backed at the ministerial and presidential level by a large number of political agreements within the framework of the ‘alliance for sustainable development’ (ALIDES).