Analysis of the Structure and Ecological Function of an Extreme Landscape in a Tropical Region of West Java, Indonesia

An extreme landscape is a spatially heterogeneous area with unusual topography that is prone to natural disasters but still exhibits interrelated structures and functions. One of the important functions of an extreme landscape is its ecological function. This study aimed to determine the structure and reveal the ecological functions of an extreme landscape in a tropical region of West Java, with special reference to Rongga Sub-district. The method used was a combination of remote sensing techniques and geographic information systems, which were required to process, analyze, and interpret Landsat 8 OLI/TIRS data. The landscape structure was quantified by landscape metrics, after which an analysis of ecological functions was carried out based on the constituent elements of the landscape. The results showed that the landscape structure of Rongga Sub-district consists of various elements of agroforestry land, open fields, settlements, shrubs, plantations, and rainfed and irrigated rice fields. Additionally, secondary forest land acted as a landscape matrix where rivers crossed as natural corridors. The amount of each element varied; agroforestry land had the highest value, indicating that this element showed a high degree of human intervention. Each patch was adjacent to other patch types, and the landscape diversity was quite high. The extreme topography of Rongga Sub-district supports the landscape connectivity and consequently the presence of wild animals in this area. Therefore, Rongga Sub-district has an essential ecological function as a refuge for protected animals living in non-conservation areas.

Research on Tracking the Behavior of the Ciobanus Forest Road over a Season Time through Specific Tests and Analysis

Forest roads are of great economic importance as they ensure the transport of logs and forest biomass toward collection and processing centers, which is why they should be evaluated periodically, in order to establish the degree of degradation and periodicity and rehabilitation methodology and procedures. The main purpose of the paper is to follow the behavior of the Ciobanus forest road through specific tests over a difficult season of 5 months, in order to diagnose the degree of surface wear and structure degradation. Regarding the traffic on this forest road, an exhaustive study was made during the 2013–2017 period, and for in situ or in laboratory tests a more complex study during the year 2018, in the March-June period was also made. Out of the total of 20 tests that evaluated the Ciobanus forest road, 5 of them were classified as appropriate and 15 unsuitable for traffic, meaning the forest road had to be completely rehabilitated. Moreover, it has been shown that this forest road is part of the category of secondary forest roads and needs a total overhaul to cope with the increasing traffic or tonnage of trucks. Through the methodology and the obtained results, the paper supports the specialists in the field of forest roads to be able to diagnose or evaluate such a road, and to realize a program and its timing for maintenance.

Cascading effect of source limitation on the granivore-mediated seed dispersal of Korean pine (Pinus koraiensis) in secondary forest ecosystems

Background Granivore-mediated seed dispersal is susceptible to changes in seed availability and silvicultural management, which alters synzoochorous interactions in the antagonism-mutualism continuum and affects the seed dispersal effectiveness (SDE), and eventually, the plant recruitment. We conducted a whole-year study of seed addition to quantify the granivores-Korean pine (Pinus koraiensis) synzoochorous interactions and the SDE in the same secondary forests with two treatments. Both treatments had seed source limitations: one was caused by the disappearance of Korean pine due to the historical disturbance, the other by pinecone harvesting in Korean pine plantations adjacent to the secondary forests. Thinning with different intensities (control, 25%, and 50%) were also performed to further explore the synzoochorous interactions and SDE in response to silvicultural management in the second type of forests. Results Source limitation increased the proportion of pre- and post-dispersal seed predation, and made the granivores-Korean pine interaction shift more towards antagonism, with the estimated SDE of 2.31 and 3.60, respectively, for the secondary forests without and with Korean pine. Thinning with different intensities did not alleviate the reactions towards antagonism but altered SDE; granivores occurrence decreased, but the proportion of pre- and post-dispersal seed predation increased, resulting in a fivefold decreased seedling recruitment in 25% thinning (the lowest SDE of 0.26). Conclusion The source limitation coupling thinning biased the synzoochorous interactions more towards antagonism and significantly lowered granivore-mediated SDE, which limited the successful recruitment of Korean pine in secondary forests. Forest managers should control pinecone harvesting, protect the synzoochorous interaction, and take into account masting event for Korean pine regeneration in the future.

Deforestation scenarios show the importance of secondary forest for meeting Panama’s carbon goals

Context Tropical forest loss has a major impact on climate change. Secondary forest growth has potential to mitigate these impacts, but uncertainty regarding future land use, remote sensing limitations, and carbon model accuracy have inhibited understanding the range of potential future carbon dynamics. Objectives We evaluated the effects of four scenarios on carbon stocks and sequestration in a mixed-use landscape based on Recent Trends (RT), Accelerated Deforestation (AD), Grow Only (GO), and Grow Everything (GE) scenarios. Methods Working in central Panama, we coupled a 1-ha resolution LiDAR derived carbon map with a locally derived secondary forest carbon accumulation model. We used Dinamica EGO 4.0.5 to spatially simulate forest loss across the landscape based on recent deforestation rates. We used local studies of belowground, woody debris, and liana carbon to estimate ecosystem scale carbon fluxes. Results Accounting for 58.6 percent of the forest in 2020, secondary forests (< 50 years) accrue 88.9 percent of carbon in the GO scenario by 2050. RT and AD scenarios lost 36,707 and 177,035 ha of forest respectively by 2030, a carbon gain of 7.7 million Mg C (RT) and loss of 2.9 million Mg C (AD). Growing forest on all available land (GE) could achieve 56 percent of Panama’s land-based carbon sequestration goal by 2050. Conclusions Our estimates of potential carbon storage demonstrate the important contribution of secondary forests to land-based carbon sequestration in central Panama. Protecting these forests will contribute significantly to meeting Panama’s climate change mitigation goals and enhance water security.

Metapocyrtus poncei sp. nov., a new weevil (Coleoptera, Curculionidae, Entiminae, Pachyrhynchini) from Davao Oriental, Mindanao Island, Philippines

A new species of the genus Metapocyrtus Heller, 1912 named Metapocyrtus poncei sp. nov. is described and illustrated. The new species was collected in the low elevation secondary forest from San Isidro, Davao Oriental. The new species can be differentiated from its congeners by the pronotum being fully covered in scales, the elytra with thick longitudinal scaly stripes from striae I-VI, and the short, acute spine at the apex of each elytron in the female.

Dynamic of the Land Use and Land Cover Change in Banyuwangi Regency From 1995-2019

The land use and land cover change phenomenon has become one concern over many regions worldwide, including Indonesia. Land use and land cover change due to human activities triggered alteration terrestrial ecosystems and its services including climate control functions. The study aimed to analyze land use and land cover change in Banyuwangi regency during 1995 – 2019. Four satellite images from acquisition year 1995, 2000, 2014 and 2019 were used to analyze the spatial and temporal changes along with field observations. The classification processes of land use and land cover included determination of training areas, supervised classification, and accuracy assessment. There are 12 land use and land cover based on supervised classification as follow primary forest, secondary forest, plantation forest, mangrove forest, plantation, settlement, cropland, paddy field, shrubs, water, fishpond and barren land. The result showed during observation period of 1995 until 2019 land use and land cover which tends to decrease are secondary forest, mangrove forest, and rice fields. On the other hand, the area of settlements, shrubs and fishponds were increased significantly.

Land Use Effect on Quality of Plateau Soils: A Case Study of Ososo in Northern Edo State, Nigeria

The study examined land use effect on quality of plateau soils, using Ososo in Northern Edo State, Nigeria as a case study. The objectives were to examine the status of soils under the different land uses and evaluate variation in the physicochemical properties of soils among the investigated sites. A total of thirty-six soil samples were collected from secondary forest, cocoa plantation and quarry site at 0 - 15 and 15 - 30 cm depths. Soil quality indicators were analyzed in the laboratory, while data were examined by descriptive and inferential statistics. Due to the effect of mining activities, quarry site had lower mean values of soil organic matter, total organic carbon, total nitrogen, available phosphorous, effective cation exchange capacity, potassium, copper and manganese while iron, zinc and calcium were lower in secondary forest. However, Na and ECEC were higher in cocoa plantation. The study further revealed that though the examined land uses had varied effects on the soil properties; quarry site impacted the soil quality parameters more negatively compared to the secondary forest and cocoa plantation land use types. Significant variation (p < 0.05) in sand, clay and available phosphorous was detected in the topsoil of the different land uses. The research concluded that the status of the soil nutrients was low. To improve the quality of the plateau soils, liming and the use of animal droppings, town refuse ash and plant remains is recommended.

The Floodplain Forests of the Mamberamo Basin, Papua, Indonesia (Western New Guinea): Vegetation, Soils, and Local Use

New Guinea is the world’s largest, most speciose, and most culturally rich tropical island, and the little-studied Mamberamo Basin of Papua (Indonesian New Guinea) is recognised among the region’s most-important areas for biological diversity. Here, we examined the floodplain forests in the indigenous territory of Papasena, within the Mamberamo-Foja Wildlife Reserve in the Mamberamo Basin. As part of a training activity with local researchers, students, and civil servants, and with the permission and assistance of the local people, we employed various methods including the field surveys detailed here. We used variable-area tree plots, transects for non-trees and soil sampling, and local informants to document 17 plots: four in old-growth dryland forest, five in old-growth swamp forests (two seasonally flooded and three permanently wet including one dominated by sago, Metroxylon sagu Rottb.), five in secondary forest (fallows), and three in gardens (two in swamps and one on dryland). In total, we measured 475 trees over 10 cm in diameter at 1.3 m (dbh). The swamp forests had high local basal areas (highest value 45.1 m2 ha−1) but relatively low statures (20 m but with emergent trees over 40 m). In total, 422 morphospecies from 247 genera and 89 different families were distinguished. These included 138 tree species and 284 non-tree plant species. A quarter (105) of the morphospecies lacked species-level identifications. The woody families Rubiaceae, Araceae, Moraceae, and Euphorbiaceae were especially diverse, with 20 or more morphospecies each. Tree richness was highest in dryland forest (plot 7 having 28 species in 40 stems over 10 cm dbh) with more variation in the flooded forests. Non-tree vegetation showed similar patterns ranging from 65 species in one 40-by-5 m primary forest plot to just 5 in one seasonally flooded forest plot. The local people identified many plants as useful. Among trees, at least 59 species were useful for construction (the most common use), while, for non-trees, medicinal uses were most frequent. Inceptisols dominated (12 plots), followed by Ultisols and Entisols (3 and 2 plots, respectively). Drainage appeared poor and nutrient availability low, while land-suitability criteria implied little potential for crops aside from sago. We discuss the implication of local practises and more recent developments that may threaten the conservation of these floodplain systems. We underline the key role of local people in the oversight and protection of these ecosystems.