scholarly journals Changes in the spatial and temporal pattern of natural forest cover on Hainan Island from the 1950s to the 2010s：implications for natural forest conservation and management

2017 ◽  
Author(s):  
Siliang Lin ◽  
Yaozhu Jiang ◽  
Jiekun He ◽  
Guangzhi Ma ◽  
Yang Xu ◽  
...  
Keyword(s):  
Forest Cover ◽  
Hainan Island ◽  
Natural Forest ◽  
Natural Forests ◽  
Ecological Value ◽  
Spatial And Temporal Patterns ◽  
Conservation Policies ◽  
The Road ◽  
Conservation Actions ◽  
The 1950S

The study of the past, present, and future state and dynamics of the tropical natural forest cover (NFC) might help to better understand the pattern of deforestation and fragmentation as well as the influence of social and natural processes. The obtained information will support the development of effective conservation policies and strategies. In the present study, we used historical data of the road network, topography, and climatic productivity to reconstruct NFC maps of Hainan Island, China, from the 1950s to the 2010s, using the random forest algorithm. We investigated the spatial and temporal patterns of NFC change from the 1950s to the 2010s and found that it was highly dynamic in both space and time. Our data showed that grid cells with low NFC were more vulnerable to NFC decrease, suggesting that conservation actions regarding natural forests need to focus on regions with low NFC and high ecological value. We also identified the hot-spots of NFC change, which provides insights into the dynamic changes of natural forests over time.

scholarly journals Changes in the spatial and temporal pattern of natural forest cover on Hainan Island from the 1950s to the 2010s: implications for natural forest conservation and management

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3320 ◽  
Author(s):  
Siliang Lin ◽  
Yaozhu Jiang ◽  
Jiekun He ◽  
Guangzhi Ma ◽  
Yang Xu ◽  
...  
Keyword(s):  
Forest Cover ◽  
Hainan Island ◽  
Natural Forest ◽  
Natural Forests ◽  
Ecological Value ◽  
Spatial And Temporal Patterns ◽  
Conservation Policies ◽  
The Road ◽  
Conservation Actions ◽  
The 1950S

The study of the past, present, and future state and dynamics of the tropical natural forest cover (NFC) might help to better understand the pattern of deforestation and fragmentation as well as the influence of social and natural processes. The obtained information will support the development of effective conservation policies and strategies. In the present study, we used historical data of the road network, topography, and climatic productivity to reconstruct NFC maps of Hainan Island, China, from the 1950s to the 2010s, using the random forest algorithm. We investigated the spatial and temporal patterns of NFC change from the 1950s to the 2010s and found that it was highly dynamic in both space and time. Our data showed that grid cells with low NFC were more vulnerable to NFC decrease, suggesting that conservation actions regarding natural forests need to focus on regions with low NFC and high ecological value. We also identified the hot spots of NFC change, which provides insights into the dynamic changes of natural forests over time.

scholarly journals Changes in the spatial and temporal pattern of natural forest cover on Hainan Island from the 1950s to the 2010s：implications for natural forest conservation and management

2017 ◽  
Author(s):  
Siliang Lin ◽  
Yaozhu Jiang ◽  
Jiekun He ◽  
Guangzhi Ma ◽  
Yang Xu ◽  
...  
Keyword(s):  
Forest Cover ◽  
Hainan Island ◽  
Natural Forest ◽  
Natural Forests ◽  
Ecological Value ◽  
Spatial And Temporal Patterns ◽  
Conservation Policies ◽  
The Road ◽  
Conservation Actions ◽  
The 1950S

The study of the past, present, and future state and dynamics of the tropical natural forest cover (NFC) might help to better understand the pattern of deforestation and fragmentation as well as the influence of social and natural processes. The obtained information will support the development of effective conservation policies and strategies. In the present study, we used historical data of the road network, topography, and climatic productivity to reconstruct NFC maps of Hainan Island, China, from the 1950s to the 2010s, using the random forest algorithm. We investigated the spatial and temporal patterns of NFC change from the 1950s to the 2010s and found that it was highly dynamic in both space and time. Our data showed that grid cells with low NFC were more vulnerable to NFC decrease, suggesting that conservation actions regarding natural forests need to focus on regions with low NFC and high ecological value. We also identified the hot-spots of NFC change, which provides insights into the dynamic changes of natural forests over time.

scholarly journals 30-year changes of natural forests under human activities in the Indochina peninsula - case studies in Cambodia, Laos and Vietnam

2021 ◽  
Vol 43 (3) ◽  
Author(s):  
Duong Nguyen Dinh ◽  
Cam Lai Vinh
Keyword(s):  
Forest Cover ◽  
Hydrological Cycle ◽  
Regional Scale ◽  
Google Earth ◽  
Natural Forest ◽  
Infrastructure Development ◽  
Natural Forests ◽  
Forest Cover Change ◽  
Remotely Sensed Data ◽  
Automated Method

Natural forests are a basic component of the earth's ecology. It is essential for biodiversity, hydrological cycle regulation, and environmental protection. Natural forests are gradually degraded and reduced due to timber logging, conversion to cropland, production forests, commodity trees, and infrastructure development. Decreasing natural forests results in loss of valuable habitats, land degradation, soil erosion, and imbalance of water cycle on the regional scale. Thus, operational monitoring of natural forest cover change has been in the interest of scientists for a long time. Current forest mapping methods using remotely sensed data provide limited capability to separate natural forests and planted forests. Natural forest statistics are often generated using official forestry national reports that have different bias levels due to different methodologies applied in different countries in forest inventory. Over the last couple of decades, natural forests have been over-exploited for various reasons. This led to forest cover degradation and water regulation capability, which results in extreme floods and drought of a watershed in general. This situation demands an urgent need to develop a fast, reliable, and automated method for mapping natural forests. In this study, by applying a new method for mapping natural forests by Landsat time series, the authors succeeded in mapping changes of natural forests of Cambodia, Laos, and Vietnam from 1989 to 2018. As a focused study area, three provinces: Ratanakiri of Cambodia, Attapeu of Laos, and Kon Tum of Vietnam were selected. The study reveals that after 30 years, 51.3% of natural forests in Ratanakiri, 27.8% of natural forests in Attapeu, and 50% of natural forests in Kon Tum were lost. Classification results were validated using high spatial resolution imagery of Google Earth. The overall accuracy of 99.3% for the year 2018 was achieved.

Extent and causes of forest cover changes in Vietnam’s provinces 1993–2013: a review and analysis of official data

2017 ◽  
Vol 25 (2) ◽  
pp. 199-217 ◽  
Author(s):  
Roland Cochard ◽  
Dung Tri Ngo ◽  
Patrick O. Waeber ◽  
Christian A. Kull
Keyword(s):  
Forest Regeneration ◽  
Forest Cover ◽  
Natural Forest ◽  
Tree Plantations ◽  
Environmental Services ◽  
Forest Transition ◽  
Natural Forests ◽  
Forest Regrowth ◽  
Forest Cover Changes ◽  
Natural Forest Regeneration

Within a region plagued by deforestation, Vietnam has experienced an exceptional turnaround from net forest loss to forest regrowth. This so-called forest transition, starting in the 1990s, resulted from major changes to environmental and economic policy. Investments in agricultural intensification, reforestation programs, and forestland privatization directly or indirectly promoted natural forest regeneration and the setting-up of plantation forests mainly stocked with exotic species. Forest cover changes, however, varied widely among regions due to specific socio-economic and environmental factors. We studied forest cover changes (including natural and planted forests) and associated drivers in Vietnam’s provinces from 1993–2013. An exhaustive literature review was combined with multivariate statistical analyses of official provincial data. Natural forest regrowth was highest in northern mountain provinces, especially in the period 1993–2003, whereas deforestation continued in the Central Highlands and Southeast Region. Forest plantations increased most in mid-elevation provinces. Statistical results largely confirmed case study-based literature, highlighting the importance of forestland allocation policies and agroforestry extension for promoting small-scale tree plantations and allowing natural forest regeneration in previously degraded areas. Results provide evidence for the abandonment of upland swidden agriculture during 1993–2003, and reveal that spatial competition between expanding natural forests, fixed crop fields, and tree plantations increased during 2003–2013. While we identified a literature gap regarding effects of forest management by para-statal forestry organizations, statistical results showed that natural forests increased in areas managed for protection/regeneration. Cover of other natural forests under the organizations’ management, however, tended to decrease or stagnate, especially more recently when the organizations increasingly turned to multi-purpose plantation forestry. Deforestation processes in the Central Highlands and Southeast Region were mainly driven by cash crop expansion (coffee, rubber) and associated immigration and population growth. Recent data trends indicated limits to further forest expansion, and logging within high-quality natural forests reportedly remained a widespread problem. New schemes for payments for forest environmental services should be strengthened to consolidate the gains from the forest transition, whilst improving forest quality (in terms of biodiversity and environmental services) and allowing local people to actively participate in forest management.

scholarly journals AUTOMATED CLASSIFICATION OF NATURAL FORESTS WITH LANDSAT TIME SERIES USING SIMPLIFIED SPECTRAL PATTERNS

2020 ◽  
Vol XLIII-B3-2020 ◽  
pp. 983-988
Author(s):  
N. D. Duong
Keyword(s):  
Time Series ◽  
Land Cover ◽  
Forest Cover ◽  
Hydrological Cycle ◽  
Regional Scale ◽  
Natural Forest ◽  
New Method ◽  
Natural Forests ◽  
Automated Method ◽  
Spectral Patterns

Abstract. Natural forests are a basic component of the earth ecology. It is essential for biodiversity, hydrological cycle regulation and environmental protection. Globally, natural forests are gradually degraded and reduced due to timber logging, conversion to cropland, production forest, commodity trees, and infrastructure development. Decreasing of natural forests results in loss of valuable habitats, land degradation, soil erosion and imbalance of water cycle in regional scale. Thus operational monitoring natural forest cover change, therefore, has been in interest of scientists for long time. Forest cover mapping methods are divided to two groups: field-based survey and remotely sensed image data based techniques. The field-based methods are conventional and they have been used widely in forestry management practice. Satellite-image-based methods were developed since beginning of earth observation. These methods, except visual image interpretation, can be grouped to supervised and unsupervised classification that rely on various algorithm as statistical, clustering or artificial intelligence. However, there is little report about method, which can extract natural forests from generic forest cover. Over the last couple of decades, natural forests have been over-exploited by various reasons. This practice led to urgent need of development of fast, reliable and automated method for mapping natural forests. In this study, a new method for mapping of natural forest by Landsat time series is presented. The new method is fully automated. It uses spectral patterns as principal classifier to recognize land cover classes. The proposed method was applied in study area consisted of Ratanakiri of Cambodia, Attapeu of Laos and Kon Tum of Vietnam. About 2000 Landsat images were used to generate land cover maps of the study area across years from 1989 to 2018.

scholarly journals Drivers of Bornean Orangutan Distribution across a Multiple-Use Tropical Landscape

2021 ◽  
Vol 13 (3) ◽  
pp. 458
Author(s):  
Sol Milne ◽  
Julien G. A. Martin ◽  
Glen Reynolds ◽  
Charles S. Vairappan ◽  
Eleanor M. Slade ◽  
...  
Keyword(s):  
Forest Cover ◽  
Food Resource ◽  
Multiple Use ◽  
Natural Forests ◽  
Bornean Orangutan ◽  
Aerial Surveys ◽  
Significant Difference ◽  
The Difference ◽  
Fig Trees ◽  
Abundance And Distribution

Logging and conversion of tropical forests in Southeast Asia have resulted in the expansion of landscapes containing a mosaic of habitats that may vary in their ability to sustain local biodiversity. However, the complexity of these landscapes makes it difficult to assess abundance and distribution of some species using ground-based surveys alone. Here, we deployed a combination of ground-transects and aerial surveys to determine drivers of the critically endangered Bornean Orangutan (Pongo pygmaeus morio) distribution across a large multiple-use landscape in Sabah, Malaysian Borneo. Ground-transects and aerial surveys using drones were conducted for orangutan nests and hemi-epiphytic strangler fig trees (Ficus spp.) (an important food resource) in 48 survey areas across 76 km2, within a study landscape of 261 km2. Orangutan nest count data were fitted to models accounting for variation in land use, above-ground carbon density (ACD, a surrogate for forest quality), strangler fig density, and elevation (between 117 and 675 m). Orangutan nest counts were significantly higher in all land uses possessing natural forest cover, regardless of degradation status, than in monoculture plantations. Within these natural forests, nest counts increased with higher ACD and strangler fig density, but not with elevation. In logged forest (ACD 14–150 Mg ha−1), strangler fig density had a significant, positive relationship with orangutan nest counts, but this relationship disappeared in a forest with higher carbon content (ACD 150–209 Mg ha−1). Based on an area-to-area comparison, orangutan nest counts from ground transects were higher than from counts derived from aerial surveys, but this did not constitute a statistically significant difference. Although the difference in nest counts was not significantly different, this analysis indicates that both methods under-sample the total number of nests present within a given area. Aerial surveys are, therefore, a useful method for assessing the orangutan habitat use over large areas. However, the under-estimation of nest counts by both methods suggests that a small number of ground surveys should be retained in future surveys using this technique, particularly in areas with dense understory vegetation. This study shows that even highly degraded forests may be a suitable orangutan habitat as long as strangler fig trees remain intact after areas of forest are logged. Enrichment planting of strangler figs may, therefore, be a valuable tool for orangutan conservation in these landscapes.

scholarly journals Effectiveness of Protected Areas in the Pan-Tropics and International Aid for Conservation

Geomatics ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 335-346
Author(s):  
Do-Hyung Kim ◽  
Anupam Anand
Keyword(s):  
Protected Areas ◽  
Forest Conservation ◽  
Forest Cover ◽  
International Aid ◽  
Asian Countries ◽  
Forest Cover Change ◽  
Average Effect ◽  
Tropical Countries ◽  
Conservation Policies ◽  
The Tropics

Evaluation of the effectiveness of protected areas is critical for forest conservation policies and priorities. We used 30 m resolution forest cover change data from 1990 to 2010 for ~4000 protected areas to evaluate their effectiveness. Our results show that protected areas in the tropics avoided 83,500 ± 21,200 km2 of deforestation during the 2000s. Brazil’s protected areas have the largest amount of avoided deforestation at 50,000 km2. We also show the amount of international aid received by tropical countries compared to the effectiveness of protected areas. Thirty-four tropical countries received USD 42 billion during the 1990s and USD 62 billion during the 2000s in international aid for biodiversity conservation. The effectiveness of international aid was highest in Latin America, with 4.3 m2/USD, led by Brazil, while tropical Asian countries showed the lowest average effect of international aid, reaching only 0.17 m2/USD.

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