scholarly journals Effects of pruning a temperate mangrove forest on the associated assemblages of macroinvertebrates

2003 ◽  
Vol 54 (5) ◽  
pp. 683 ◽  
Author(s):  
William Gladstone ◽  
Maria J. Schreider
Keyword(s):  
Mangrove Forest ◽  
Forest Canopy ◽  
Sampling Period ◽  
Mangrove Forests ◽  
Short Term ◽  
Macrobenthic Assemblages ◽  
Highly Correlated ◽  
Taxonomic Groups ◽  
Macroinvertebrate Fauna ◽  
Similarity Matrices

Mangrove forests around the world are being impacted by development in adjacent land and water areas. An after-control-impact study was undertaken to assess the effects of mangrove forest pruning on the associated benthic macroinvertebrate fauna. Pruning, undertaken 5 years before our sampling period, reduced the height of the forest canopy from 5 m to 1 m. Macrobenthic assemblages were sampled in September 2000 and January 2001 from two randomly selected sites within the pruned section of forest, and two sites in each of two control locations in the same forest. Assemblage composition in the pruned and undisturbed mangrove forests was not significantly different, nor were there significant differences in variability between the two areas. Similarity matrices for assemblages based on higher taxonomic groups and molluscs were highly correlated with similarity matrices for all taxa, indicating the utility of more rapid forms of assessment in this habitat. The results suggest that although short-term impacts may have occurred, no impact on macroinvertebrate assemblages was evident 5 years after the pruning.

scholarly journals Impacts of exotic mangrove forests and mangrove deforestation on carbon remineralization and ecosystem functioning in marine sediments

2010 ◽  
Vol 7 (2) ◽  
pp. 2631-2671 ◽  
Author(s):  
A. K. Sweetman ◽  
J. J. Middelburg ◽  
A. M. Berle ◽  
A. F. Bernardino ◽  
C. Schander ◽  
...  
Keyword(s):  
Community Structure ◽  
Ecosystem Functioning ◽  
Mangrove Forest ◽  
Mangrove Forests ◽  
Short Term ◽  
Benthic Respiration ◽  
Faunal Abundance ◽  
Carbon Remineralization ◽  
And Control ◽  
Mangrove Biomass

Abstract. To evaluate how mangrove invasion and removal can modify benthic carbon cycling processes and ecosystem functioning, we used stable-isotopically labelled algae as a deliberate tracer to quantify benthic respiration and C-flow through macrofauna and bacteria in sediments collected from (1) an invasive mangrove forest, (2) deforested mangrove sites 2 and 6 years after removal of above-sediment mangrove biomass, and (3) two mangrove-free, control sites in the Hawaiian coastal zone. Sediment oxygen consumption (SOC) rates were significantly greater in the mangrove and mangrove removal site experiments than in controls and were significantly correlated with total benthic (macrofauna and bacteria) biomass and sedimentary mangrove biomass (SMB). Bacteria dominated short-term C-processing of added microalgal-C and benthic biomass in sediments from the invasive mangrove forest habitat. In contrast, macrofauna were the most important agents in the short-term processing of microalgal-C in sediments from the mangrove removal and control sites. Mean faunal abundance and short term C-uptake rates in sediments from both removal sites were significantly higher than in control cores, which collectively suggest that community structure and short-term C-cycling dynamics in habitats where mangroves have been cleared can remain fundamentally different from un-invaded mudflat sediments for at least 6-yrs following above-sediment mangrove removal. In summary, invasion by mangroves can lead to large shifts in benthic ecosystem function, with sediment metabolism, benthic community structure and short-term C-remineralization dynamics being affected for years following invader removal.

scholarly journals Evaluasi Tingkat Kekritisan Hutan Mangrove dengan Menggunakan Teknologi Spasial di Kawasan Pesisir Timur Aceh

2020 ◽  
Vol 4 (1) ◽  
pp. 682-689
Author(s):  
Nur Fathanah ◽  
Yulia Dewi Fazlina ◽  
Abubakar Karim
Keyword(s):  
Mangrove Forest ◽  
Forest Canopy ◽  
Critical Level ◽  
Development Planning ◽  
Coastal Areas ◽  
Mangrove Forests ◽  
Time Period ◽  
Forest Canopy Density ◽  
Type Of Land Use ◽  
Spatial Technology

Abstrak. Hutan mangrove di pesisir Kota Langsa semakin lama semakin terancam keberadaannya. Penyalahgunaan hutan mangrove yang dilakukan dalam kurun waktu akhir-akir ini telah menimbulkan berbagai kerusakan sehingga menyebabkan tingkat kekritisannya semakin tinggi. Salah satu upaya yang dapat dilakukan untuk mengatasi hal tersebut adalah dengan memanfaatkan teknologi spasial. Teknologi spasial merupakan salah satu media yang penting untuk melakukan perencanaan pembangunan dan pengelolaan sumber daya alam dengan cakupan yang luas. Penelitian ini bertujuan untuk mengetauhi seberapa besar tingkat kekrtitisan hutan mangrove sehingga dapat dilakukan upaya pemulihan bagi hutan mangrove dengan tingkat kekritisan yang tinggi. Kriteria yang digunakan untuk mengetahui tigkat kekrtitisan hutan mangrove yaitu jenis penggunaan lahan, kerapatan tajuk tanaman, dan ketahanan tanah terhadap abrasi. Hasil penelitian menunjukkan hutan mangrove dengan tingkat kekritisan tertinggi terjadi di kawasan pesisir Langsa bagian timur dengan kategori sangat kritis seluas 453,25 Ha atau 42,16 %, sedangkan hutan mangrove yang termasuk kategori kritis seluas 1.108,99 Ha atau 44%, serta yang tegolong ke dalam kategori tidak kritis seluas 2.337,78 Ha atau 56.70%.Critical Level of Mangrove Forest Using Spatial Technology Case Study in Coastal Areas of LangsaAbstract. Mangrove forests in coastal areas of Langsa are increasingly threatened. The misuse of mangrove forests that have been carried out at the end-time period has caused various damage, causing the critical level to be higher. One effort that can be done to overcome this problem is to utilize spatial technology. Spatial technology is one of the important media for carrying out extensive development planning and natural resource management The purpose of this study is to determine the critical level of mangrove forests so that recovery efforts can be done for mangrove forests with highest criticality level. The criteria used to determine the critical level of mangrove forests are the type of land use, forest canopy density, and soil resistance to abrasion. The results showed that the highest critical level of mangrove forest occurred in the eastern coastal areas of Langsa with very critical category is 453.25 ha or 42.16%, mangrove forests included in the critical category is 1,108.99 ha or 44%, and those classified to the non-critical category is 2,337.78 ha or 56.70%. 

scholarly journals Impacts of exotic mangrove forests and mangrove deforestation on carbon remineralization and ecosystem functioning in marine sediments

2010 ◽  
Vol 7 (7) ◽  
pp. 2129-2145 ◽  
Author(s):  
A. K. Sweetman ◽  
J. J. Middelburg ◽  
A. M. Berle ◽  
A. F. Bernardino ◽  
C. Schander ◽  
...  
Keyword(s):  
Community Structure ◽  
Ecosystem Functioning ◽  
Mangrove Forest ◽  
Mangrove Forests ◽  
Short Term ◽  
Benthic Respiration ◽  
Faunal Abundance ◽  
Carbon Remineralization ◽  
And Control ◽  
Mangrove Biomass

Abstract. To evaluate how mangrove invasion and removal can modify short-term benthic carbon cycling and ecosystem functioning, we used stable-isotopically labeled algae as a deliberate tracer to quantify benthic respiration and C-flow over 48 h through macrofauna and bacteria in sediments collected from (1) an invasive mangrove forest, (2) deforested mangrove sites 2 and 6 years after removal of above-sediment mangrove biomass, and (3) two mangrove-free control sites in the Hawaiian coastal zone. Sediment oxygen consumption (SOC) rates averaged over each 48 h investigation were significantly greater in the mangrove and mangrove removal site experiments than in controls and were significantly correlated with total benthic (macrofauna and bacteria) biomass and sedimentary mangrove biomass (SMB). Bacteria dominated short-term C-processing of added microalgal-C and benthic biomass in sediments from the invasive mangrove forest habitat and in the 6-yr removal site. In contrast, macrofauna were the most important agents in the short-term processing of microalgal-C in sediments from the 2-yr mangrove removal site and control sites. However, mean faunal abundance and C-uptake rates in sediments from both removal sites were significantly higher than in control cores, which collectively suggest that community structure and short-term C-cycling dynamics of sediments in habitats where mangroves have been cleared can remain fundamentally different from un-invaded mudflat sediments for at least 6-yrs following above-sediment mangrove removal. In summary, invasion by mangroves can lead to dramatic shifts in benthic ecosystem function, with sediment metabolism, benthic community structure and short-term C-remineralization dynamics being affected for years following invader removal.

Economic value analysis of mangrove forest ecosystems in Sorong, West Papua Province

2014 ◽  
pp. 39
Author(s):  
Roger R Tabalessy
Keyword(s):  
Mangrove Forest ◽  
Economic Value ◽  
Forest Degradation ◽  
Primary Data ◽  
Mangrove Forests ◽  
Value Analysis ◽  
Human Needs ◽  
The People ◽  
West Papua ◽  
Mangrove Wood

Coastal areas can either meet the human needs or give great contribution to the development. However, rapid infrastrural development in Sorong, west Papua, has been followed by high demand for mangrove timber and caused mangrove forest degradation due to exploitation. This exploitation could also result from high economic value of the mangrove timber. This study was done to analyze the economic value of mangrove wood utilized by the people to support the development process in Sorong. This study used primary data obtained through interviews and the economic value calculation of mangrove forests. It found that Sorong had mangrove economic value of IDR 165,197,833, 491. Wilayah pesisir selain dapat memenuhi kebutuhan hidup manusia juga memberikan kontribusi yang besar bagi pembangunan. Cepatnya pembangunan infrastruktur di Kota Sorong diikuti pula dengan tingginya permintaan akan kayu mangrove dan menyebabkan terjadinya degradasi hutan mangrove akibat eksploitasi. Eksploitasi ini disebabkan juga akibat kayu mangrove memiliki nilai ekonomi. Penelitian yang dilakukan ini bertujuan untuk menganalisis nilai ekonomi kayu mangrove yang dimanfaatkan oleh masyarakat Kota Sorong dalam proses menunjang pembangunan. Penelitian ini menggunakkan data primer yang diperoleh melalui hasil wawancara dan perhitungan nilai ekonomi hutan mangrove. Hasil penelitian ini menunjukkan nilai ekonomi ekosistem hutan mangrove yang berada di Kota Sorong adalah Rp165.197.833.491.

scholarly journals Mangrove Forest Landcover Changes in Coastal Vietnam: A Case Study from 1973 to 2020 in Thanh Hoa and Nghe An Provinces

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 637
Author(s):  
Huong Thi Thuy Nguyen ◽  
Giles E. S. Hardy ◽  
Tuat Van Le ◽  
Huy Quoc Nguyen ◽  
Hoang Huy Nguyen ◽  
...  
Keyword(s):  
Mangrove Forest ◽  
Monsoon Season ◽  
Coastal Development ◽  
Northern Coast ◽  
Mangrove Forests ◽  
Visual Interpretation ◽  
Mangrove Restoration ◽  
Coast Of Vietnam ◽  
Landsat Satellite

Mangrove forests can ameliorate the impacts of typhoons and storms, but their extent is threatened by coastal development. The northern coast of Vietnam is especially vulnerable as typhoons frequently hit it during the monsoon season. However, temporal change information in mangrove cover distribution in this region is incomplete. Therefore, this study was undertaken to detect change in the spatial distribution of mangroves in Thanh Hoa and Nghe An provinces and identify reasons for the cover change. Landsat satellite images from 1973 to 2020 were analyzed using the NDVI method combined with visual interpretation to detect mangrove area change. Six LULC classes were categorized: mangrove forest, other forests, aquaculture, other land use, mudflat, and water. The mangrove cover in Nghe An province was estimated to be 66.5 ha in 1973 and increased to 323.0 ha in 2020. Mangrove cover in Thanh Hoa province was 366.1 ha in 1973, decreased to 61.7 ha in 1995, and rose to 791.1 ha in 2020. Aquaculture was the main reason for the loss of mangroves in both provinces. Overall, the percentage of mangrove loss from aquaculture was 42.5% for Nghe An province and 60.1% for Thanh Hoa province. Mangrove restoration efforts have contributed significantly to mangrove cover, with more than 1300 ha being planted by 2020. This study reveals that improving mangrove restoration success remains a challenge for these provinces, and further refinement of engineering techniques is needed to improve restoration outcomes.

scholarly journals Assessing the Natural Recovery of Mangroves after Human Disturbance Using Neural Network Classification and Sentinel-2 Imagery in Wunbaik Mangrove Forest, Myanmar

2020 ◽  
Vol 13 (1) ◽  
pp. 52
Author(s):  
Win Sithu Maung ◽  
Jun Sasaki
Keyword(s):  
Neural Network ◽  
Change Detection ◽  
Transfer Learning ◽  
Mangrove Forest ◽  
Kappa Coefficient ◽  
Mangrove Forests ◽  
Ann Model ◽  
Shrimp Ponds ◽  
Natural Recovery ◽  
Sentinel 2

In this study, we examined the natural recovery of mangroves in abandoned shrimp ponds located in the Wunbaik Mangrove Forest (WMF) in Myanmar using artificial neural network (ANN) classification and a change detection approach with Sentinel-2 satellite images. In 2020, we conducted various experiments related to mangrove classification by tuning input features and hyper-parameters. The selected ANN model was used with a transfer learning approach to predict the mangrove distribution in 2015. Changes were detected using classification results from 2015 and 2020. Naturally recovering mangroves were identified by extracting the change detection results of three abandoned shrimp ponds selected during field investigation. The proposed method yielded an overall accuracy of 95.98%, a kappa coefficient of 0.92, mangrove and non-mangrove precisions of 0.95 and 0.98, respectively, recalls of 0.96, and F1 scores of 0.96 for the 2020 classification. For the 2015 prediction, transfer learning improved model performance, resulting in an overall accuracy of 97.20%, a kappa coefficient of 0.94, mangrove and non-mangrove precisions of 0.98 and 0.96, respectively, recalls of 0.98 and 0.97, and F1 scores of 0.96. The change detection results showed that mangrove forests in the WMF slightly decreased between 2015 and 2020. Naturally recovering mangroves were detected at approximately 50% of each abandoned site within a short abandonment period. This study demonstrates that the ANN method using Sentinel-2 imagery and topographic and canopy height data can produce reliable results for mangrove classification. The natural recovery of mangroves presents a valuable opportunity for mangrove rehabilitation at human-disturbed sites in the WMF.

FACTORS INFLUENCING THE MORTALITY OF SCOLYTUS MULTISTRIATUS (COLEOPTERA: SCOLYTIDAE) IN ELM BRANCHES IN CALIFORNIA

1985 ◽  
Vol 117 (7) ◽  
pp. 819-828 ◽  
Author(s):  
Ann E. Hajek ◽  
Donald L. Dahlsten
Keyword(s):  
Small Diameter ◽  
Sampling Period ◽  
Scolytus Multistriatus ◽  
Bark Thickness ◽  
Branch Diameter ◽  
Factors Influencing ◽  
Strong Positive Relationship ◽  
Egg Density ◽  
Ulmus Procera ◽  
Highly Correlated

AbstractPopulations of Scolytus multistriatus (Marsham) from two areas of California were sampled in 1979 to investigate various factors influencing mortality. English-elm bolts (Ulmus procera Salisb.) ranging between 2.0 and 12.9 cm in diameter yielded mean mortalities from 49.1 to 86.0%. Mortality was highly correlated with egg density for branch samples from 7.0 to 12.9 cm in diameter. The minimum acceptable elm-branch diameter (2.8 cm) was attacked only during the first sampling period (mid-May to mid-June). Branch diameter, and therefore bark thickness, demonstrated a strong positive relationship with the density of S. multistriatus eggs, attacks, gallery lengths, and emerged adults. Gallery length density was positively correlated with attack density. At low attack densities in small-diameter branches, mean gallery lengths were shorter.

scholarly journals Cold Wave-Induced Reductions in NDII and ChlRE for North-Western Pacific Mangroves Varies with Latitude and Climate History

2021 ◽  
Vol 13 (14) ◽  
pp. 2732
Author(s):  
Jonathan Peereman ◽  
J. Aaron Hogan ◽  
Teng-Chiu Lin
Keyword(s):  
Water Content ◽  
Geographic Distribution ◽  
Low Temperatures ◽  
Forest Canopy ◽  
Cold Wave ◽  
Mangrove Forests ◽  
Climate History ◽  
Wave Effects ◽  
Northern Pacific ◽  
Wave Induced

Mangrove forests growing at the poleward edges of their geographic distribution are occasionally subject to freezing (<0 °C) and cold wave (>0 °C) events. Cold wave effects on mangrove trees are well documented and adaptation to cold stress has been reported for local mangrove populations in the North Atlantic. However, there is less understanding of effects of cold waves on mangroves in the northern Pacific, especially at the regional scale. Moreover, it is unclear if cold tolerant mangrove species of North Asia display variation in resistance to cold temperatures across their geographic distribution. Using a cold wave event that occurred in January 2021, we evaluated the effects of low temperatures on vegetation index (VI) change (relative to a recent five-year baseline) for mangrove forests dominated by Kandelia obovata (Rhizophoraceae) and Avicennia marina (Acanthaceaee) at the northern edge of their geographical range. We used two VIs derived from Sentinel-2 imagery as indicators for canopy health: the normalized difference infrared index (NDII) and the chlorophyll red-edge index (ChlRE), which reflect forest canopy water content and chlorophyll concentration, respectively. We isolated the cold wave effects on the forest canopy from phenology (i.e., cold wave induced deviation from a five-year baseline) and used multiple linear regression to identify significant climatic predictors for the response of mangrove forest canopy VI change to low temperatures. For areas where the cold wave resulted in temperatures <10 °C, immediate decreases in both VIs were observed, and the VI difference relative to the baseline was generally greater at 30-days after the cold wave than when temperatures initially recovered to baseline values, showing a slight delay in VI response to cold wave-induced canopy damage. Furthermore, the two VIs did not respond consistently suggesting that cold-temperature induced changes in mangrove canopy chlorophyll and water content are affected independently or subject to differing physiological controls. Our results confirm that local baseline (i.e., recent past) climate predicts canopy resistance to cold wave damage across K. obovata stands in the northern Pacific, and in congruence with findings from New World mangroves, they imply geographic variation in mangrove leaf physiological resistance to cold for Northern Pacific mangroves.

scholarly journals ASSESSMENT OF MANGROVE FOREST DEGRADATION THROUGH CANOPY FRACTIONAL COVER IN KARIMUNJAWA ISLAND, CENTRAL JAVA, INDONESIA

2016 ◽  
Vol 3 (2) ◽  
pp. 107 ◽  
Author(s):  
Muhammad Kamal ◽  
Hartono Hartono ◽  
Pramaditya Wicaksono ◽  
Novi Susetyo Adi ◽  
Sanjiwana Arjasakusuma
Keyword(s):  
Mangrove Forest ◽  
Forest Canopy ◽  
Vegetation Index ◽  
Spectral Response ◽  
Empirical Relationship ◽  
Forest Degradation ◽  
Empirical Method ◽  
Estimation Accuracy ◽  
Fractional Cover ◽  
Semi Empirical

The Karimunjawa Islands mangrove forest has been subjected to various direct and indirect human disturbances in the recent years. If not properly managed, this disturbance will lead to the degradation of mangrove habitat health. Assessing forest canopy fractional cover (fc) using remote sensing data is one way of measuring mangrove forest degradation. This study aims to (1) estimate the forest canopy fc using a semi-empirical method, (2) assess the accuracy of the fc estimation and (3) create mangrove forest degradation from the canopy fc results. A sample set of in-situ fc was collected using the hemispherical camera for model development and accuracy assessment purposes. We developed semi-empirical relationship models between pixel values of ALOS AVNIR-2 image (10m pixel size) and field fc, using Enhanced Vegetation Index (EVI) as a proxy of the image spectral response. The results show that the EVI provides reasonable estimation accuracy of mangrove canopy fc in Karimunjawa Island with the values ranged from 0.17 to 0.96 (n = 69). The low fc values correspond to vegetation opening and gaps caused by human activities or mangrove dieback. The high fc values correspond to the healthy and dense mangrove stands, especially the Rhizophora sp formation at the seafront. The results of this research justify the use of simple canopy fractional cover model for assessing the mangrove forest degradation status in the study area. Further research is needed to test the applicability of this approach at different sites.

scholarly journals Ecological relations between mangrove leaf litter and the spatial distribution of the gastropod Melampus coffeus in a fringe mangrove forest

2015 ◽  
Vol 105 (1) ◽  
pp. 35-40 ◽  
Author(s):  
Diva S. Tavares ◽  
Rafaela C. Maia ◽  
Cristina Rocha-Barreira ◽  
Helena Matthews-Cascon
Keyword(s):  
Spatial Distribution ◽  
Leaf Litter ◽  
Mangrove Forest ◽  
Atlantic Coast ◽  
Ground Surface ◽  
Mangrove Forests ◽  
Physical Presence ◽  
Ecological Relations ◽  
Melampus Coffeus ◽  
Pulmonate Gastropod

Leaf litter represents a food source to many organisms that may directly contribute to organic matter decomposition. In addition, the physical presence of these vegetal detritus contributes for the modification of some environmental areas and produce microhabitats that may act as a refuge against predators and desiccation for many animals. The pulmonate gastropod Melampus coffeus (Linnaeus, 1758) (Ellobiidae) is a very common specie in Atlantic Coast mangrove forests and feeds on fallen mangrove leaves. It was hypothesized that the spatial distribution of Melampus coffeus is directly affected by mangrove leaf litter biomass deposition. Thus, this research aimed at evaluating the spatial distribution of these gastropods in relation to the biomass of mangrove leaf litter through a twelve-month period. The study area was established in the middle estuary of Pacoti River, state of Ceará, Brazil where two adjacent zones with different topographic profiles were determined. Samples of Melampus coffeus and leaf litter were collected monthly, throughout a year, from the mangrove ground surface. The results indicated that the presence of twigs in mangrove litter favor the occupation by smaller individuals of M. coffeus, probably because smaller individuals are more susceptible to predator attacks and desiccation than larger ones, and twigs and branches may provide a safe microhabitat.

Sign in / Sign up

Export Citation Format

Share Document