Food from the Sulawesi Sea, the need for integrated sea use planning
Siahainenia, Audrie J. - \ 2016
Wageningen University. Promotor(en): Herbert Prins; Johan Verreth, co-promotor(en): Fred de Boer. - Wageningen : Wageningen University - ISBN 9789462578869 - 180
mangroves - mangrove forests - fishes - habitats - marine areas - marine environment - fish stocks - environmental management - ecological disturbance - disturbance - sulawesi - mangroves - mangrovebossen - vissen - habitats - mariene gebieden - marien milieu - visstand - milieubeheer - ecologische verstoring - verstoring - celebes
Mangroves occur in the tropics and subtropics region and an important coastal habitat for the artisanal fisheries along the coast of Indonesia. Around 19% of the total mangrove area in the world is located in Indonesia. Besides providing a barrier against coastal/Delta erosion, mangrove forest plays a significant role as a nursery area for most of the marine communities. Unluckily, 57% of the ±3.2 million ha of the mangroves in Indonesia is currently in degraded, mostly because of human activities (anthropogenic disturbance). The primary sources of anthropogenic disturbances to mangroves are increasing population growth rate and demand for seafood products as an essential protein, especially the wild shrimp, in the world market. These resulted in land-use conversion along estuarine areas not only for settlements and plantations but also for aquaculture ponds. The lack of awareness and understanding of the value and function of mangrove ecosystems contributed to the loss and damage the mangroves area.
Therefore, my research and field experiment aimed to quantify the effects of human disturbance on mangroves associated trophic cascades in Indonesia estuarine areas. The study was performed in the Berau District, East Kalimantan, Indonesia between 2005 and 2010. Data of mangrove extent from 1990 in the Berau Delta was used as base data with low human disturbance. We also interviewed the artisanal fishermen about their catches, origins, and fishing locations, in relation to the total catch per unit effort (CpUE).
The results had shown that the total mangroves area in the Berau Delta decreased by 54% between the 1990 and 2009, which led to fragmentation and alteration in the structural complexity of mangroves. The field experiment conducted at three locations with different levels of human disturbances revealed that the species richness was decreased with increased the level of human interference and the marine community tended to be dominated by only a few species. In the highly disturbed areas, the catch of small-scale fishermen tended to be lower. Furthermore, the result from a spatial statistical model indicated that the disturbance of mangrove habitats was influenced the distribution pattern of shrimp. The total CpUE of small-scale fishery in the study area was relatively small, and the area was probably not overexploited.
As a conclusion, mangroves habitat in the Berau Delta played a significant role in sustaining coastal fisheries. This important ecosystem supports a primary source of marine protein. Mangrove forests can only guarantee these marine resources if the people consciously maintain its viability through a strong management policy.
Forests and trees for social adaptation to climate variability and change
Pramova, E. ; Locatelli, B. ; Djoudi, H. ; Somorin, O.A. - \ 2012
Wiley Interdisciplinary Reviews: Climate Change 3 (2012)6. - ISSN 1757-7780 - p. 581 - 596.
ecosystem-based adaptation - environmental services - adaptive capacity - tropical forests - mangrove forests - agricultural intensification - coastal vegetation - natural insurance - coping strategies - food security
Ecosystems provide important services that can help people adapt to climate variability and change. Recognizing this role of ecosystems, several international and nongovernmental organizations have promoted an ecosystem-based approach to adaptation. We review the scientific literature related to ecosystem-based adaptation (EBA) with forests and trees, and highlight five cases in which forests and trees can support adaptation: (1) forests and trees providing goods to local communities facing climatic threats; (2) trees in agricultural fields regulating water, soil, and microclimate for more resilient production; (3) forested watersheds regulating water and protecting soils for reduced climate impacts; (4) forests protecting coastal areas from climate-related threats; and (5) urban forests and trees regulating temperature and water for resilient cities. The literature provides evidence that EBA with forests and trees can reduce social vulnerability to climate hazards; however, uncertainties and knowledge gaps remain, particularly for regulating services in watersheds and coastal areas. Few studies have been undertaken on EBA specifically, but the abundant literature on ecosystem services can be used to fill knowledge gaps. Many studies assess the multiple benefits of ecosystems for human adaptation or well-being, but also recognize trade-offs between ecosystem services. Better understanding is needed of the efficiency, costs, and benefits, and trade-offs of EBA with forests and trees. Pilot projects under implementation could serve as learning sites and existing information could be systematized and revisited with a climate change adaptation lens.
Water pollution by intensive brackish shrimp farming in south-east Vietnam: Causes and options for control
Pham Thi Ahn, ; Kroeze, C. ; Bush, S.R. ; Mol, A.P.J. - \ 2010
Agricultural Water Management 97 (2010)6. - ISSN 0378-3774 - p. 872 - 882.
of-california ecoregion - mangrove forests - environmental-impact - nitrogen budget - aquaculture - pond - thailand - sustainability - effluent - alternatives
This paper focuses on both the environmental impact of intensive shrimp farming in the coastal region of Vietnam and the identification of options for cleaner production. We investigated water pollution, sediment contamination and the spread of diseases related to shrimp farming in the Can Gio district of Ho Chi Minh City (Vietnam), an area representative for the impacts of intensive shrimp production in the country. Data on the production process was compiled from site observations, interviews with local farmers and experts, as well as from secondary sources. The results indicate that, while a large number of individual farms may exceed environmental standards, intensive shrimp farming is not always associated with waste streams exceeding water quality standards. This is interesting because it shows currently available technologies can reduce pollution from intensive shrimp farms. The paper concludes by identifying technologically and economically feasible options for reducing water pollution, problems associated with contaminated sediment, and the spread of diseases.
Remote sensing techniques for mangrove mapping
Vaiphasa, C. - \ 2006
Wageningen University. Promotor(en): Andrew Skidmore; Herbert Prins, co-promotor(en): Fred de Boer. - [S.l. ] : S.n. - ISBN 9789085043539 - 129
mangroves - mangrovebossen - vegetatie - remote sensing - karteren - classificatie - mangroves - mangrove forests - vegetation - remote sensing - surveying - classification
Mangroves, important components of the world's coastal ecosystems, are threatened by the expansion of human settlements, the boom in commercial aquaculture, the impact of tidal waves and storm surges, etc. Such threats are leading to the increasing demand for detailed mangrove maps for the purpose of measuring the extent of the decline of mangrove ecosystems. Detailed mangrove maps at the community or species level are, however, not easy to produce, mainly because mangrove forests are very difficult to access. Without doubt, remote sensing is a serious alternative to traditional field-based methods for mangrove mapping, as it allows information to be gathered from the forbidding environment of mangrove forests, which otherwise, logistically and practically speaking, would be extremely difficult to survey. Remote sensing applications for mangrove mapping at the fundamental level are already well established but, surprisingly, a number of advanced remote sensing applications have remained unexplored for the purpose of mangrove mapping at a finer level. Consequently, the aim of this thesis is to unveil the potential of some of the unexplored remote sensing techniques for mangrove studies. Specifically, this thesis focuses on improving class separability between mangrove species or community types. It is based on two important ingredients:
(i) the use of narrow-band hyperspectral data, and
(ii) the integration of ecological knowledge of mangrove-environment relationships into the mapping process.
Overall, the results of this study reveal the potential of both ingredients. They show that delicate spectral details of hyperspectral data and the spatial relationships between mangroves and their surrounding environment help to improve mangrove class separability at the species level. Despite the optimism generated by the overall results, it was found that appropriate data treatments and analysis techniques such as spectral band selection and noise reduction were still required to harness essential information from both hyperspectral and ecological data. Thus, some aspects of these data treatments and analysis techniques are also presented in this thesis. Finally, it is hoped that the methodology presented in this thesis will prove useful and will be followed for producing mangrove maps at a finer level.
|Remote sensing as a tool for identification of aquacultural systems and mangrove species in the coastal Mekong delta, Vietnam
Koopmanschap, E. ; Vullings, W. ; Mensvoort, M.E.F. van; Quang Tri, Le; Tromp, M. - \ 2002
In: Selected papers of the workshop on integrated management of coastal resources in the Mekong delta, Vietnam : Can Tho, Vietnam, August 2000 / van Mensvoort, M.E.F., Quang Tri, Le, - p. 45 - 56.
mangroves - mangrovebossen - aquacultuur - remote sensing - delta's - vietnam - bebossing - geo-informatie - mangrovebos - Azië - Mekong - mangroves - mangrove forests - afforestation - aquaculture - remote sensing - deltas - vietnam
The aquaculture activities (shrimp farms) resulted in an unsustainable system with polluted surface water and disease outbreaks. Shrimp farms are nowadays often abandoned again and reforestation is an option
|Growth of Rhizophora mangroves in Vietnam affected by salinity
Haanstra, L. ; Van Be, Le; Elemans, M. ; Diemont, W.H. - \ 2002
In: Selected papers of the workshop on integrated management of coastal resources in the Mekong delta, Vietnam : Can Tho, Vietnam, August 2000 / van Mensvoort, M.E.F., Quang Tri, Le, - p. 37 - 43.
mangroves - mangrovebossen - gewasproductie - verzilting - plant-water relaties - modellen - vietnam - bodem - bosbouw - houtproductie - mangrove - overstroming - Azië - Mekong - mangroves - mangrove forests - crop production - salinization - plant water relations - models - vietnam
|Silvicultural management and land characteristics affecting the growth of rhizopora apiculata in Thanh Phu, Ben Tre Province, Mekong delta, Vietnam
Mensvoort, M.E.F. van; McKenzie, P. - \ 2002
In: Workshop on integrated management of coastal resources in the Mekong delta, Vietnam, Can Tho, Vietnam / van Mensvoort, M.E.F., Le Quang, Tri, Wageningen : Wageningen University - ISBN 9789067546744 - p. 57 - 64.
bodemgeschiktheid - mangrovebossen - bodemzoutgehalte - gewasproductie - vietnam - soil suitability - soil salinity - mangrove forests - crop production - vietnam
During the Indo-China war an estimated 200,000 ha of Vietnamese mangrove forests were destroyed by chemical warfare. Since the war clearance for aquaculture and population pressure caused further deforestation, particularly in the Mekong delta. Mangrove reforestation is desired. At the state farm at Thanh Phu a combined mangrove - shrimp system has been applied for about ten years