Primary Forest Areas Research Articles

Multiparameter analysis of small non-flying mammals' response to forest restoration post-bauxite mining in eastern Amazonia.

Bauxite mining has been caused severe changes in the natural ecosystems of the Amazon, but the restoration of these areas is mandatory by federal law in Brazil. The recolonization of fauna is crucial to establishing the ecological functions of recovering forests, and the small nonflying mammals can stand out in this process. Assessing taxonomic and functional diversity parameters, we demonstrated that in the early stages of forest recovery post-bauxite mining, between 6 and 11 years, it is possible to restore approximately 45% of the richness of small non-flying mammal species from the original habitats, that in this case were altered Primary Forests. However, the species richness parameter alone does not reflect the recovery of taxonomic or functional diversity at this stage of forest succession. Although 34.8% of the species composition is shared between the Altered Primary Forest and Forest Areas in Restoration, the abundance distribution per species is less balanced in the latter habitat. The areas did not exhibit significant difference between the functional divergence and functional evenness of ecological functions performed by small nonflying mammals; however, they present differences in terms of the functional richness. We also observed that some functional traits of species, such as larger body mass, are more closely related to the structural characteristics of the Primary Forest, such as high basal area values, litter and percentage forest cover. In the forest recovery areas, we observed a predominance of terrestrial species and those with granivorous and insectivorous diets. Furthermore, our results highlight the importance of applying different taxonomic and functional diversity parameters to understand better the fauna recovery patterns in degraded areas undergoing restoration.

Predation of a rare white-faced tree rat Echimys chrysurus by the Ornate Hawk-eagle Spizaetus ornatus in a lowland Amazonian rainforest

The Echimys chrysurus is a medium-sized rodent of the family Echimyidae found mainly in the Amazon, being rare and difficult to record. In this note, we describe the predation of E. chrysurus by an individual of Ornate Hawk-Eagle, Spizaetus ornatus, in a primary forest area, in western Pará, Brazil. This unprecedented record is an important contribution to the knowledge of the ecology and natural history of both species and provides important insights about their ecology and basic biology.

Restoration Evaluation of National Forest Park in Greater Khingan Mountains Region, China

As an important part of ecological civilization construction and harmonious coexistence between man and nature, the importance of restorative environment construction in national forest parks is self-evident. In this paper, the national forest park in the Greater Khingan Mountains region covering a large area of primary forest is taken as the research object. Based on visual perception, PRS, skin conductance level, and eye tracking technology are used as evaluation indexes to conduct restoration experiments on individuals. Among 60 participants, the PRS total scores for lawn space, shady space, dense forest space, and hard space were 166.63, 164.63, 168.43, and 158.93, respectively, indicating good restorative benefits, with hard space scoring lower. SCR decreases for dense forest space (M = 0.52) were significantly greater than for hard space (M = 0.38), suggesting better stress reduction. Eye tracking data showed that dense forest space had the longest total fixation duration (M = 42.57) and hard space the highest fixation count (M = 42.73). The results show that the national forest park is beneficial to the recovery of individual psychology and physiology, and can reduce the pressure of people’s visual perception. The psychological and physiological restorative benefits of different spatial scene types are different. Moreover, there is correlation between the eye movement index, psychological evaluation index, and physiological evaluation index, which confirms the possibility of introducing the eye movement index into the study of restorative environments.

The Regeneration Potential of Kasa (Castanopsis acuminatissima Blume) in Kalaena Nature Reserve, East Luwu Regency

Kasa is one of the important species among 120 species in the genus Castanopsis (Fagaceae), which thrives in secondary and primary lowland forest areas up to 1000 m above sea level. This plant species exhibits tolerance to full sunlight. The objective of this study is to assess the regeneration potential of Kasa (Castanopsis acuminatissima Blume) in the Kalaena Nature Reserve. The research plots consisted of two 50m x 50m plots, with a nested 10m x 10m subplot placed using purposive sampling. The findings regarding the regeneration potential of Kasa in the Kalaena Nature Reserve revealed varying numbers of seedlings, saplings, poles, and trees. The regeneration potential of Kasa is influenced by the growth stages of seedlings and trees. During the seedling phase, the regeneration potential of Kasa is classified as very good. However, the density of trees, although in the productive category, is low due to environmental factors and the characteristics of the parent tree. Conversely, the sapling and pole phases exhibit very poor regeneration potential. In plot 1, there were 1,964 individual seedlings, 6 individual saplings, 4 individual poles, and 21 individual trees. Meanwhile, plot 2 recorded 844 individual seedlings, 5 individual saplings, 1 individual pole, and 18 individual trees. The growth of Kasa in both plots displayed a clustered pattern.

How large felids of South America are influenced by environmental and anthropogenic variables in the most degraded portion of the Amazon

AbstractWe evaluated the most relevant natural and anthropogenic factors for the occurrence and co‐occurrence of jaguars (Panthera onca) and pumas (Puma concolor) in the eastern Amazon, the most degraded portion of this tropical rainforest in Brazil. We found that in a context of high human pressure, a more significant amount of primary forest and more significant annual rainfall most positively influence the occurrence of jaguars. In contrast, pumas are negatively influenced by proximity to roads and positively by slope. Additionally, the presence of primary forest areas and high annual rainfall also favour the co‐occurrence of jaguars and pumas in the same areas. In contrast, open areas more related to anthropogenic zones disfavour the co‐occurrence of these two species in this degraded portion of the Amazon. Our results support landscape management for conserving big cat species in the Amazon and reinforce the importance of forest conservation for maintaining big cats in altered landscapes. Although these animals occur in open habitats, in the Amazon, these species are dependent on primary forests, as they are better‐structured habitats that maintain the capacity to support prey and shelter.

Struktur Tegakan dan Tutupan Kanopi Ekosistem Hutan dan Parak di Kecamatan Lubuk Kilangan Kota Padang

This study aimed to determine the stand structure and tree canopy cover in forest and parak ecosystems in Lubuk Kilangan District, Padang City. This is a descriptive research with a direct observation throught purposive random sampling method. Data were collected by making six of 20 x 20 m plots in each primary forest and parak ecosystem. Tree diameters ≥10 cm were measured in each plot and canopy cover were collected using the Hemispherical Photography method using a mobile phone front camera equipped with a fish-eye lens. Data were analyzed in terms of stand density, basal area, Stand Basal Area (SBA), and percentage of canopy cover. The average tree density in the primary forest area was 913 individuals/ha, while the tree density in the parak was 467 individuals/ha. The SBA value in the primary forest was higher than in the parak, which was 64.10 m2/ha in the primary forest and 14,72 m2/ha in the parak. The average percentage of canopy cover in both areas shows that the percentage of primary forest canopy cover was greater than that of parak. The average value of the percentage of canopy cover in the forest area was 80.48%, while in the parak area was 71.23%. Correlation between tree density, canopy cover, SBA was only occured in primary forest area where the canopy cover negatively correlated with SBA. This study showed that the primary forest area and parak in Lubuk Kilangan Subdistrict have a good tree density, SBA and tree canopy covers.

Changes in land use and land cover in forest areas in Bener Meriah and Aceh Tengah Districts, Indonesia

This research aims to obtain information regarding land use and land cover (LULC) changes in forest areas in Bener Meriah and Aceh Tengah Districts in 2000-2021, especially on the loss and gain of forest areas, and conversion between land cover classes. We used Landsat 5 (TM) satellite imagery data recorded in 2000 and 2006, and Landsat 8 (OLI) satellite imagery recorded in 2014 and 2020/2021 on path/row data, namely 130/57. The classification processes of LULC included the determination of training areas, supervised classification, and accuracy assessment. The LULC in Bener Meriah and Aceh Tengah districts are dominated by primary dryland forest and secondary dryland forest 250348.45 ha (53.65%) and 103153.16 ha (22.11%), respectively; other land covers, plantation forest 45601.12 ha (9.77%) and shrubs 314722.96 ha (6.74%). However, there is a very significant increase in mixed dryland agriculture areas, from 3186.33 ha (0.68%) in 2000 to 19283.26 ha (4.13%) in 2021. Forest area management has shown a positive trend by significantly increasing in primary dryland forest areas, but there has also been a significant increase in mixed dryland agriculture areas. It is important to find solutions to prevent the spread of deforestation and maintain the sustainability and services of forest ecosystems.

Pemetaan Zonasi Daerah Rawan Kebakaran Hutan Berbasis Sistem Informasi Geografis (SIG) di Kawasan Taman Nasional Kerinci Seblat

This study aims to determine the zoning level of vulnerability and the distribution of forest fire prone areas in the TNKS SPTN Region III Painan Resort Kambang. This research uses descriptive method with quantitative approach. Data analysis techniques used are scoring and overlay. The results showed 1) The level of forest fire vulnerability there are two classes of vulnerability, low class of 173,015.62 hectares generally located in the rain forest. Medium class 115,14.76 hectares are in primary and secondary dryland forest areas, fields, dryland farms, rice fields and shrubs.2) The distribution of fire-prone areas there are a total of 31 hotspots, moderate category 24 points are in dryland farms mixed with shrubs and fields, high category 6 points are in rainforest areas and dryland farms mixed with shrubs, for low category 1 point is in the rainforest area. Based on this data, it can be concluded that most of the forests in Kambang Resort are in the medium and low vulnerability class zones.

The Diversity of Stingless Bees (Hymenoptera: Meliponini) in Belaban Resort, Bukit Baka Bukit Raya National Park

Kelulut (Hymenoptera: Meliponini) is a honey-producing bee and belongs to the eusocial bee group. Kelulut is also a pollinating insect that is widespread in the world, including Indonesia. The study of kelulut diversity can describe the composition of kelulut in an area and the condition of an ecosystem. This study aimed to obtain data and information on kelulut diversity in three different forest areas (primary forest, secondary forest, and ecosystem restoration area). The study was conducted by capturing kelulut using sugar solution bait traps and free sampling. The results obtained were analyzed using the Shannon-Wiener Diversity Index (H'), the Evenness index (E) and the Simpson Dominance Index (C). A total of 747 individuals from 12 types of kelulut were found in this study. The secondary forest gets the highest H' value (1.869), followed by the primary forest (1.672) and ecosystem restoration area (1.159). The diversity of stingless bees is higher in forested areas due to environmental factors such as temperatures within the normal range (25.5-28.9°C), the availability of trees for nesting, and the abundance of food sources from flowers.

Remarks on the diversity and echolocation calls of hipposiderid bats (Chirroptera: Hipposideridae) in Cuc Phuong National Park, northeastern Vietnam

Cuc Phuong is the oldest and most well-known National Park in Vietnam. With its large primary forest area and karst cave systems, it is assumed to be an ideal home to a highly diverse bat fauna. However, species diversity and echolocation of bats in this park are poorly characterized. Between April 2021 and April 2022, three bat surveys were conducted in the park with special attention on the species of the family Hipposideridae. The bat specimens collected previously from the park were also examined. According to past records, hipposiderids in the park comprised at least seven species: Aselliscus stoliczkanus, Coelops frithii, Hipposideros alongensis, Hipposideros armiger, Hipposideros gentilis, Hipposideros lylei and Hipposideros poutensis. In this series of field surveys, six of these seven species were captured while Coelops frithii was only confirmed from specimen examination. Each species is clearly distinguishable by their morphology and echolocation calls. This study provides the first comparison of echolocation calls of all seven species which will be useful for potential acoustic identification and monitoring bats in the park and surrounding areas in future.

Loss of carbon stock as an impact of anthropogenic activities in a protected mangrove forest

Abstract. Eddy S, Setiawan AA, Taufik M, Oktavia M, Utomo B, Milantara N. 2023. Loss of carbon stock as an impact of anthropogenic activities in a protected mangrove forest. Biodiversitas 24: 6493-6501. The significant anthropogenic activities within the mangrove forest, known as the Air Telang Protected Forest (ATPF) in the Banyuasin District, South Sumatra, Indonesia, have led to an alarming degradation, leaving only its primary mangrove forests, currently constituting approximately 26% of the total forest area. This study aims to analyze changes in land cover, quantify carbon reserve loss due to CO2 emissions, and assess carbon sequestration in the ATPF over two periods: 1999-2010 and 2010-2023. Remote sensing data for 1999, 2010, and 2023 were utilized from Landsat imagery, employing ENVI and ArcGIS for land cover classification. Carbon density, CO2 emissions, and carbon sequestration were analysed using the Land Use Planning for Multiple Environmental Services (LUMENS) software. The research findings reveal an increase in the primary forest area in the first period (by almost a quarter); however, more than half of this area was lost in the second period. The secondary forest area consistently decreased over the two periods, while the open area experienced significant growth. Carbon stocks in 2010 exceeded those in 1999 due to an increase in the primary forest area, but by 2023, carbon stocks decreased significantly due to extensive land clearing. The second period witnessed the largest emissions, exceeding those of the previous period by five times. Carbon sequestration in the first period surpassed that in the second period by more than three times, with the most significant sequestration resulting from the growth of secondary mangrove forests into primary mangrove forests. The study highlights the necessity of restoration and conservation of mangrove forest areas in ATPF for sustenance of its natural function as a protected forest.

Migrations agricoles, dynamique de dégradation du couvert forestier et émergence de systèmes agro-forestiers à base de cacaoyer dans la Sous-préfecture de Bléniméouin (Ouest-ivoirien)

Expansion of cultivation camps, dynamics of degradation of forest cover and emergence of cocoa-based agro-forestry systems in the Sub-prefecture of Bléniméouin (Western Côte d'Ivoire) The Sub-prefecture of Bléniméouin is part of the western forest region of Côte d'Ivoire, home to the new pioneer fronts of the country for the past two decades. Due to its natural potential (maintenance of a few scraps of primary forest, hot and humid climate, etc.) and its very dynamic plantation economy, this territory is experiencing strong land pressure which results in agricultural migrations and the expansion of cultivation camps. Alongside the dwindling of land reserves, new agroforestry practices have been emerging since the end of the 2010-2020 decade. Thus, the objective of this study is to analyze the agrarian and landscape changes induced by the expansion of cultivation camps in the said Sub-prefecture. To achieve this objective, a multi-date analysis based on the exploitation of Landsat images (TM 1980, ETM+ 2000 and Oli/Tirs 2021) coupled with S.I.G was adopted and supplemented by field observations. The results reveal significant regressive forest cover dynamics. From 1980 to 2021, the area of ​​primary forest has increased from 6499 ha or 29% of the space to 1360 ha or 6%. The area lost by the forest has been converted mainly into areas of perennial crops (60%), food crops (37%) and bare soils (3%). Faced with land saturation, rural people are developing new agro-forestry techniques combining cashew, cocoa and rubber orchards in order to create more ecological conditions beneficial to all kinds of crops (food crops and perennials).

Amazon deforestation: simulated impact of Brazil's proposed BR-319 highway project.

The scenario of deforestation in the Amazon may change with the reconstruction of Highway BR-319, a long-distance road that will expand the region's agricultural frontier towards the north and west of the Western Amazon, stretches that until then have extensive areas of primary forest due to the hard access. We simulate the deforestation that would be caused by the reconstruction and paving of Highway BR-319 in Brazil's state of Amazonas for the period from 2021 to 2100. The scenarios were based on the historical dynamics of deforestation in the state of Amazonas (business as usual, or BAU). Two deforestation scenarios were developed: (a) BAU_1, where Highway BR-319 is not reconstructed, maintaining its current status, and (b) BAU_2, where the reconstruction and paving of the highway will take place in 2025, favoring the advance of the deforestation frontier to the northern and western portion of the state of Amazonas. In the scenario where the highway reconstruction is foreseen (BAU_2), the results show that deforestation increased by 60% by 2100 compared to the scenario without reconstruction (BAU_1), demonstrating that paving would increase deforestation beyond the limits of the highway's official buffer area (40 km). The study showed that protected areas (conservation units and indigenous lands) help to maintain forest cover in the Amazon region. At the same time, it shows how studies like this one can help in decision-making.

Analysis of land use (2013-2022) in the Gayo highlands, Aceh, Indonesia

Forest fragmentation is a threat to ecosystems in Indonesia caused by forest conversion to plantations. This study aims to analyze the use of land cover in the period 2013-2022. The research was conducted from November 2022 to January 2023 in the Gayo highland area by taking case studies in 2 regions including the Central Aceh District and Bener Meriah District. The research was carried out in several stages, namely: image pre-processing, image visual interpretation, making image classification class identifiers, and ground checking. The pre-processing stage is the preparation of tools and materials. Landsat 8 OLI imagery for the study area downloaded from the United States Geological Survey (USGS) website. The results of the research show that in the last 10 years there has been a decrease in the area of land cover in the exploration area of primary forest and secondary forest. Meanwhile, in the cultivation of dry fields, settlements, plantations and vacant land, land use has increased. Changes in the use of land cover are influenced by community activities in Central Aceh and Bener Meriah Regencies.

Changes in Coleopteran assemblages over a successional chronosequence in a Mexican tropical dry forest.

Coleopterans are the most diverse animal group on Earth and constitute good indicators of environmental change. However, little information is available about Coleopteran communities' responses to disturbance and land-use change. Tropical dry forests have undergone especially extensive anthropogenic impacts in the past decades. This has led to mosaic landscapes consisting of areas of primary forest surrounded by pastures, agricultural fields and secondary forests, which negatively impacts many taxonomic groups. However, such impacts have not been assessed for most arthropod groups. In this work, we compared the abundance, richness and diversity of Coleopteran morphospecies in four different successional stages in a tropical dry forest in western Mexico, to answer the question: How do Coleopteran assemblages associate with vegetation change over the course of forest succession? In addition, we assessed the family composition and trophic guilds for the four successional stages. We found 971 Coleopterans belonging to 107 morphospecies distributed in 28 families. Coleopteran abundance and richness were greatest for pastures than for latter successional stages, and the most abundant family was Chrysomelidae, with 29% of the individuals. Herbivores were the most abundant guild, accounting for 57% of the individuals, followed by predators (22%) and saprophages (21%) beetles. Given the high diversity and richness found throughout the successional chronosequence of the studied tropical dry forest, in order to have the maximum number of species associated with tropical dry forests, large tracts of forest should be preserved so that successional dynamics are able to occur naturally.

Comparison of Forest Restorations with Different Burning Severities Using Various Restoration Methods at Tuqiang Forestry Bureau of Greater Hinggan Mountains

Forest disturbances and restoration are key processes in carbon transmission between the terrestrial surface and the atmosphere. In boreal forests, fire is the most common and main disturbance. The reconstruction process for post-disaster vegetation plays an essential role in the restoration of a forest’s structure and function, and it also maintains the ecosystem’s health and stability. Remote sensing monitoring could reflect dynamic post-fire features of vegetation. However, there are still major differences in the remote sensing index in terms of regional feasibility and sensibility. In this study, the largest boreal primary coniferous forest area in China, the Greater Hinggan Mountains forest area, was chosen as the sampling area. Based on time series data from Landsat-5 TM surface reflectance (SR) and data obtained from sample plots, the burned area was extracted using the Normalized Burn Ratio (NBR). We used the pre- and post-fire difference values (dNBR) and compared them with survey data to classify the burn severity level. The Normalized Difference Vegetation Index (NDVI) (based on spectrum combination) and the Disturbance Index (DI) (based on Tasseled-Cap transformation) were chosen to analyze the difference in the degree of burn severity and vegetation restoration observed using various methods according to the sequential variation feature from 1986 to 2011. The results are as follows: (1) The two remote sensing indexes are both sensitive to fire and the burn severity level. When a fire occurred, the NDVI value for that year decreased dramatically while the DI value increased sharply. Alongside these findings, we observed that the rangeability and restoration period of the two indexes is significantly positively correlated with the degree of burn severity. (2) According to these two indexes, natural vegetation restoration was faster than the restoration achieved using artificial methods. However, compared with the NDVI, the DI showed a clearer improvement in restoration, as the restoration period the DI could evaluate was longer in two different ways: the NDVI illustrated great changes in the burn severity in the 5 years post-fire, while the DI was able to show the changes for more than 20 years. Additionally, from the DI, one could identify felling activities carried out when the artificial restoration methods were initially applied. (3) From the sample-plot data, there were few differences in forest canopy density—the average was between 0.55 and 0.6—between the diverse severity levels and restoration methods after 33 years of recovery. The average diameter at breast height (DBH) and height values of trees in naturally restored areas decreased with the increase in burn severity, but the values were obviously higher than those in artificially restored areas. This indicates that both the burn severity level and restoration methods have important effects on forest restoration, but the results may also have been affected by other factors.

Sustainability Analysis of Primary Forest Areas in The Perspective of Income and Gross Domestic Regional Product Inequality (Vector Autoregressive Approach)

Jambi Province is a province on Sumatra Island with a land area of 5,016,005 hectares, of which 2,098,535 ha are forest areas. With the potential of existing resources, Jambi province's economic growth in the last ten years has been on a positive trend, but for the period 2006 to 2018, experienced significant land degradation which causes the shrinkage of the province natural forest areas. This research aims to analyze the relationship that occurs between variables of primary forest areas, income inequality, and economic growth in Jambi Province by using the vector autoregression method followed by stationarity test, optimum lag test, cointegration test, var stability test, variance decomposition, and granger causality test. Based on the causality of the three research variables, the Granger causality test results indicate that there is a unidirectional causality between income inequality that occurs in Jambi Province and the percentage of primary forest area in Jambi Province that is still available. In addition, the results of the VAR analysis show that based on the t-statistic value, income inequality in period eight significantly affected the percentage of primary forest area in Jambi Province in the following year. Besides that, based on the coefficient, income inequality negatively affected primary forest areas the following year in period eight. The results of the Decomposition Variant test predicted that in period 1, the primary forest area variable affected 99.98% of the primary forest area variable. Income inequality had an effect of 0.02% on primary forest areas, and economic growth in period one did not affect primary forest areas. Predictions for the 10th period show that the primary forest area affects 52.62% of the primary forest area, while 29.81% and 17.56% of the primary forest area in the 10th period are affected by income inequality and economic growth. The analysis above shows the critical role of primary forests in Jambi Province for the existing inequality and economic growth in Jambi Province. Deforestation and non-optimal primary forest management can have a negative impact on the value of income inequality in Jambi Province. Therefore, a policy framework on forestry in Jambi Province is needed that involves the development of plantation forests as an effort that could overcome the decrease in wood supply.

Presence of understory dwarf bamboo determines ecosystem fine root production in a cool-temperate forest in northern Japan

ABSTRACT Fine root biomass (FRB) and production (FRP) are crucial in forest carbon and nutrient cycling, but the factors controlling FRB and FRP are not well understood. Here, we examined FRB, FRP, aboveground environmental and stand factors, and soil environmental factors in four stands in a forest covered with dense understory vegetation of dwarf bamboo, Sasa senanensis (hereafter, Sasa). The four stands had different tree species composition and included a primary forest (PF), secondary forest (SF), conifer plantation (CP), and Sasa area (SA). We quantified the FRB and FRP of trees and Sasa separately using the ingrowth core method. Total FRP was higher in stands with substantial presence of Sasa (99–130 g m−2 yr−1) than in CP with scarce Sasa (69 g m−2 yr−1). Despite being occupied by Sasa alone, SA had high FRP, suggesting that the presence of Sasa regardless of trees is a key determinant of ecosystem FRP. Tree FRB increased with increasing tree aboveground biomass, tree density, or basal area at breast height, but Sasa FRB and total FRB decreased. Total FRP was also lower at higher values of these aboveground stand factors. In Sasa, specific root length was significantly higher, and root tissue density was significantly lower, than in trees, indicating the capacity of Sasa for explosive growth. Positive correlations between Sasa FRB or FRP and soil inorganic N or ammonium contents (i.e. N availability) were detected. We conclude that Sasa is important in determining FRB and FRP in this northern forest with understory vegetation.

Precipitation Variability for Protected Areas of Primary Forest and Pastureland in Southwestern Amazônia

Daily and monthly rainfall data provided by surface rain gauges in the Amazon Basin are sparse and defective, making it difficult to monitor rainfall patterns for certain portions of its territory, in this sense, estimations of precipitation from remote sensing calibrated with rain gauge data are key to overcome this problem. This paper presents a spatiotemporal analysis of the precipitation distribution for Rondônia State, in southwestern Amazonia. Data from Climate Hazards Group InfraRed Precipitation and Station (CHIRPS) were analyzed, using a pooled time analysis of a forty-year period (1981–2020). Data obtained from remote sensing were validated by rain gauges distributed over the study region. Pixel-by-pixel trend analyzes were developed by applying the Mann-Kendall test and Sen’s slope test to study the magnitude of the trend. The analysis revealed that CHIRPS presents a tendency to underestimate precipitation values in most cases. Among the metrics, mean values between very good (<±15%) and good (±15–±35%) were observed using PBIAS; mean RMSE values range from 57.8 mm to 107.9 mm; an average agreement level of 0.9 and an average SES of 0.5; and good fit for the linear regression model (average R2 > 0.70) for about 64.7% of the stations. Sen’ slope spatialization results show a reduction of approximately −15 mm year−1, with decrease mainly in the Northern Region of Rondônia, which has extensive areas where the native forest has been replaced by pasture.

The use of multi-sensor satellite imagery to analyze flood events and land cover changes using change detection and machine learning techniques in the Barito watershed

Indonesia is one of the countries in the world that is frequently affected by floods. Flood disasters can have various negative impacts and therefore need to be analyzed to determine prevention and mitigation measures. This study examined land cover change, flood detection, and flood distribution using multitemporal Sentinel-1 and Landsat-8 satellite imagery in the Barito watershed. A combination of change detection and the application of the Otsu algorithm was used to detect floodplains from Sentinel-1 imagery. Land use/land cover (LULC) changes are detected using a combination of change detection and machine learning in the form of a random forest algorithm. The overlay technique was used to analyze the distribution of floodplains. In this study, the floodplain in the study area was mapped to 109,623 ha. The change detection method detects a decrease in the areas of primary forest, secondary forest, fields, rice fields, shrubs and ponds, respectively, by 13,020 ha, 116,235 ha, 259 ha, 146,696 ha, 47,308 ha, and 9,601 ha. Settlements, bare land, plantations and water bodies increase by 14,879 ha, 64,830 ha, 218,916 ha, and 34,768 ha, respectively. Flooding was mainly found in the classes of rice fields, water bodies and primary forests.