Configuration of Allocated Mangrove Areas and Protection of Mangrove-Dominated Muddy Coasts: Knowledge Gaps and Recommendations

Mangrove-dominated muddy coasts have been allocated for developing livelihood models, particularly in developing countries. Uncontrolled allocation causes the mangrove forests to be vulnerable and even severely eroded. Restoration of vulnerable and eroded coastal areas has been merely conservation-driven, leaving livelihood-oriented mangrove forests unprotected. As a consequence, mangrove-dominated muddy coasts have not been well-protected. How livelihood-oriented mangrove forests are configured towards protecting coasts and protecting local livelihoods remains a challenge. This study employed a critical review for addressing this matter. The results reveal that there is limited practical knowledge of configuring livelihood-oriented models for protecting the coasts. The configuration process reported in this study is merely based on technical recommendations in South East Asia to date. The recommended configuration commences with the first stage of voluntarily designating a certain percentage of allocated forests on the seaward side to protect coasts, relocating livelihood models in the gaps among current stands of mangrove forests landward. Abandoned ponds are ecologically restored using sediment trapping structures for providing suitable substrate for promoting regrowth of local mangrove species as the second stage, followed by designation of an appropriate percentage as mangrove belts on the seaward side. The two-step configuration is highly likely to be replicable and applicable nationally and regionally due to full consideration of different political, sociocultural, and environmental characteristics in Vietnam and Indonesia.

Afsluitdijk climate resilient with XblocPlus

<p>The Afsluitdijk forms 32 km of the primary sea defence of the Netherlands. The Afsluitdijk was built as a closure dam in 1932 and separates the IJsselmeer from the Wadden-Sea and North Sea. Because of climate change the Afsluitdijk needs to be strengthened. A higher crest height is required to limit overtopping at higher water levels due to sea level rise. Heavier armour is required to protect the Afsluitdijk from higher wave heights. Because of the historic value of the Afsluitdijk, stringent architectural requirements are in place on the visual appearance of the dam after strengthening [1]. Therefore, a new concrete armour unit was developed to provide protection of the seaward side of the Afsluitdijk. This armour unit is called XblocPlus. The development of the armour unit is based on the breakwater armour unit Xbloc which has been applied since 2004. A saving of 56% on CO2 footprint was achieved compared to the Clients reference design.</p>

Marine microorganisms as amber inclusions: insights from coastal forests of New Caledonia

Marine microorganisms trapped in amber are extremely rare in the fossil record, and the few existing inclusions recovered so far originate from very few pieces of Cretaceous amber from France. Marine macroscopic inclusions are also very rare and were recently described from Cretaceous Burmese amber and Early Miocene Mexican amber. Whereas a coastal setting for the amber source forests is generally proposed, different scenarios have been suggested to explain how these marine inclusions can become trapped in a resin of terrestrial origin. These scenarios include an introduction of marine organisms (i) through high tides, (ii) from storms and resulting in flooding of the littoral/estuarine forest floor, (iii) in resin dropped into the sea in mangrove-type settings, or (iv) by wind and sea spray. We investigated the possibility of a wind-driven introduction of marine microorganisms into tree resins using modern coastal conifer forests with the highly resinous Cook pine (Araucaria columnaris) in New Caledonia as a model for the Cretaceous amber forests from France. By exposing fresh resin surfaces on the seaward side of the trees and the collection of older in situ resins, we confirmed that marine microorganisms can become trapped on sea-exposed resin, along with remnants from terrestrial organisms, and salt crystals. We suggest that, for cases where only a few marine inclusions are discovered in an amber deposit, an origin from aeolian background deposition is feasible. However, a more energetic but possibly still aeolian event is likely needed to explain the high numbers of marine microorganisms embedded in pieces of Cretaceous amber from France.

Utilization of land reclamation in Manado City

Reclamation activities conducted in the Bay of Manado, at the seaward side on Pierre Tendean Street (Boulevard), has changed the face of the city of Manado including the coastal area. The purpose of this study was to determine whether the realization of reclamation activities seen were as planned. The second purpose was to determine the appropriate policy strategy to ensure that the utilization of reclaimed land can be optimal. The data was collected through observation to compare actual conditions with the original plan. For policy options, SWOT (Strengths, Weaknesses, Opportunities, Threats) analysis was used. The study revealed that there are changes from the original plan, such as the extent of the area was originally planned 1185 m2, but the actual area was 781.305 m2. Based on the results of the SWOT analysis, the most appropriate policy option adopted is to optimize the role of land reclamation as one economic driving force in the city of Manado. These include the completion of a number of legal problems in reclamation© Kegiatan reklamasi yang telah dilakukan di Teluk Manado, memanjang dari Utara ke Selatan Kota Manado ke arah laut telah merubah wajah Kota Manado termasuk di dalamnya tata ruang dan pemanfaatan lahan yang baru di wilayah pesisir. Penelitian yang telah dilakukan bertujuan untuk mengkaji realisasi aktual dari kegiatan reklamasi apakah sesuai dengan peruntukannya, menentukan strategi kebijakan yang tepat dari pemanfaatan lahan reklamasi agar dilakukan dengan optimal dan ramah lingkungan. Pengumpulan data telah dilakukan secara deskriptif melalui observasi dan pengamatan lapangan untuk membandingkan kondisi aktual dengan rencana semula. Sebagai pilihan penentuan kebijakan penelitian, data dianalisis dengan menggunakan analisis SWOT (Strengths, Weaknesses, Opportunities, Threats). Hasil penelitian mengungkap bahwa adanya perubahan pemanfaatan dari rencana awal luasan kurang lebih 1.185.000 m2, menjadi luasan yang terealisasi sampai saat penelitian dilakukan mencapai luas kurang lebih 781.305 m2. Hasil analisis SWOT menunjukkan bahwa kebijakan Pemerintah Kota Manado harus konsisten dalam menetapkan perijinan, dengan tidak merubah fungsi lahan dan lingkungan pesisir. Dampak positif yang ditimbulkan dalam rangka mengoptimalisasi pemanfaatan lahan reklamasi sebagai salah satu lokasi yang dapat meningkatkan perekonomi dan pendapatan daerah, penyerapan tenaga kerja di Kota Manado. Kebijakan perubahan fungsi dan penambahan luas lokasi yang tidak sesuai dengan perencanaan awal dapat berdampak pada masalah hukum di wilayah pesisir©

Distribution and conservation status of the Critically Endangered Scrophularia takesimensis, a plant endemic to Ulleung Island, Republic of Korea

Scrophularia takesimensis Nakai is a Critically Endangered plant species endemic to Ulleung Island, Republic of Korea. We provide updated information on the distribution and conservation status of this species. We located 39 subpopulations and counted a total of 443 individuals, including some reintroduced. Observations of dried and broken branches, with fruits, of S. takesimensis along the coast may indicate dispersal by sea. The construction of coastal roads is the main threat to the species. To conserve this species more effectively we recommend that: (1) the two habitats identified as a priority for conservation should be afforded special protection, (2) habitats to the seaward side of coastal roads are more suitable than habitat on the landward side for in situ conservation, and (3) the presently known subpopulations require continuous protection and monitoring.

ARTIFICIAL BEACH BUILDING ON THE CROISETTE WATERFRONT AT CANNES

In view of the persistent increase m traffic density on the Croisette and the restrictions caused by a one-way system which had to be introduced, the Cannes municipality decided to ease the situation by widening the road to handle two-way traffic. Numerous schemes for widening the road on the seaward side were proposed but none were satisfactory for the resulting gains were minimal, and the beach, which is at present very narrow and even non-existent at certain places (see fig. 2), would have suffered accordingly. Consulted on this problem, Sogreah decided to examine the possibility of rebuilding the beach to start with, to be followed by the construction of a new, wide promenade, the net effect being a wider beach than the existing one. Since the beach could not be expected to extend naturally, this involved the construction of a completely man-made beach. This artificial beach building is extremely attractive from a technical point of view, since it presents no snags but it was nevertheless considered advisable to verify that this method could be applied to the Croisette beach. The Cannes Council Technical Department commissioned Sogreah to do a study, the aim of which was to discover whether the artificial beach would be sufficiently stable without extensive maintenance. This report is a record of these studies and the practical achievements they made possible.

STABILITY OF GIRDER BRIDGE AGAINST TSUNAMI FLUID FORCE

The horizontal and vertical components of the fluid force and pressure acting on a girder bridge due to tsunami like a solitary wave are measured in a hydraulic experiment and their characteristics are discussed. The peak of the impact fluid force is estimated on the basis of the change in the added mass of the structure. The wave pressure acting on the seaward side of the girder of the bridge is also estimated. The critical force for the stability of the girder bridge is estimated as the strength of bolts used in the shoes against shear stress.

The effect of causeway construction on seagrass meadows in the Western Pacific ? a lesson from the ancient city of Nan Madol, Madolenihmw, Pohnpei, FSM

Two seagrass meadow sites were chosen at Nan Madal adjacent to the now permeable remnants of an ancient causeway constructed 500 to 700 years ago: one immedlately on the shoreward side of the causeway, and one immediately on the seaward side. The shoreward site had greater seagrass cover, canopy height, algal abundance, and epiphyte abundance and lower species diversity (both seagrass and macro-algae), as well as muddier sediments than the seaward site. The abundance of associated fauna did not appear to differ between sites, although the composition of the faunal communities was different. On the seaward site, average epiphyte cover was less than onetenth the epiphyte cover of that on the shoreward side. Halimeda species were the most common algae on the seaward side, while on the shoreward side Hypnea species were dominant. Cymodocea rotundata was the dominant seagrass species (54% of seagrass cover) on the seaward site, but was absent on the shoreward site, which was dominated by Thalassia hemprichii (84%) and Enhalus acoroides (16%). There was no difference in salinity between the two sites. Sediments had a higher proportion of fine mud shoreward. The beche-de-mer, Holothuria atra, was common on the seaward side of the causeway, but not on the shoreward side. The causeway is open to water flow at all tide heights and does not appear to influence water height in any way. The effects of even this simple permeable barrier on seagrass meadows are evident and include differences in seagrass species, algal species, and fauna. We discuss the management lesson from this historic location for present-day Pacific island causeway developments.