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Settlement expansion and commercial agriculture affect landscape sustainability and ecosystem service provision. Integrated landscape approaches are promoted to negotiate trade-offs between competing land uses and their reconciliation. Incorporating local perceptions of landscape dynamics as basis for such negotiations is particularly relevant for sub-Saharan Africa, where most people depend on natural ecosystems for livelihoods and well-being. This study applied participatory scenario building and spatially explicit simulation to unravel perceptions of the potential impact of rubber and settlement expansion on the provision of selected ecosystem services in southwestern Ghana under a business-as-usual scenario. We collected data in workshops and expert surveys on locally relevant ecosystem services, their indicator values, and the probable land-use transitions. The data was translated into an assessment matrix and integrated into a spatially explicit modeling platform, allowing visualization and comparison of the impact on ecosystem service provision of land-use scenarios under rubber plantation and settlement expansion. The results show the capacity of current (2020) and future land-use patterns to provide locally relevant ecosystem services, indicating a decline in capacity of ecosystem service provisioning in the future compared to the 2020 land-use patterns, a threat to the benefits humans derive from ecosystems. This highlights urgent need for policies and measures to control the drivers of land-use/land-cover change. Furthermore, the results emphasize the importance of diversifying land-use/land-cover types for sustainable landscape development. The paper contributes new insights into how spatially explicit and semi-quantitative methods can make stakeholder perceptions of landscape dynamics explicit as a basis for implementing integrated landscape approaches. [ABSTRACT FROM AUTHOR]

Soil fertility assessment is essential for effective land management practices. This study was carried out to investigate the impact of three land use types Cassava farm (CF), Oil palm plantation (OPP) and Rubber plantation (RP) on soil properties in Oguta area of Imo State, Nigeria. Randomized sampling technique was implored in the collection of nine soil samples from each of the different land use within a depth of 15cm. Samples obtained from each land use were homogenized to form three composite samples per land use. The data generated from laboratory analysiswere subjected to analysis of variance (ANOVA). Sand particles had a mean of 82.7 %, 66.7 % and 76.0 % for soils under CF, OPP and RP respectively. The mean values of silt and clay particles were 8.3 % and 9.0 %; 21.0 % and 12.3 %; 13.0 % and 11.0 % in CF, OPP and RP respectively. The other soil chemical properties did not differ significantly with the exception of pH and exchangeable K. The pH (H2O) had mean of 6.43, 6.17 and 5.73 of soils under CF, OPP and RP respectively while exchangeable K had mean of 0.38 Cmol/kg for CF, 1.71 Cmol/kg for OPP and 0.61 Cmol/kg for RP. Despite not showing significant difference, OPP and RP have more soil quality attributes than CF. However, the result from this study pointed that land use influence soil properties at various rates. Hence, use of good soil management practices is required to improve the soil quality attributes. [ABSTRACT FROM AUTHOR]

Climate change is visible as climatic events like flood and drought. Floods have a major impact on soil properties by altering them through dilution, transporting and deposition of minerals. Kerala had a flood on August 2018 with a different duration or temporal variation from three to seven days due to heavy and unexpected rain from June to mid of August 2018, that triggered large landslides on that month. The current study was focussed on the impact of flood on soil chemical properties (pH, soil EC, organic carbon, available NPK) at Thrissur district of Kerala in forest, rubber, nutmeg (homegarden), coconut and open land use systems. Soil samples were collected from flood affected and adjacent non flood affected of these land use systems from 0–20 cm depth after six months of flood and analysed chemical properties according to standard methods. The result of soil pH analysis showed a greater significant decrease in coconut plantation (6.28 to 4.94) after flood. Forest, rubber and homegarden showed an increase in organic carbon (OC) (0.22, 0.77, 0.45% respectively), available P (36.85, 32.6, 38.42 kg/ha respectively). Forest showed a higher amount of available N (84 kg/ha) after flood while rubber, nutmeg and open land use systems showed a decrease in available nitrogen (201.6, 107.1, and 207.9 kg/ha decrease respectively. Forest (196.6 kg/ha), rubber plantation (299.4 kg/ha), nutmeg plantation (292 kg/ha), coconut plantation (421.4 kg/ha) and open condition (125.7 kg/ha) showed a decrease in available K content after flood. Tree based land use systems showed a remarkably better resilience or masked the ill effect of flood very quickly compared to other systems. Integration of shade tolerant species (Grewia robusta, Ailanthus triphysa and Vateria indica) in coconut plantation would help the plantation to adapt flood like situation from soil nutrient loss, also it would increase the productivity of land by maximum utilisation of land resources. [ABSTRACT FROM AUTHOR]

Determining the age of land use and land cover (LULC) using satellite imagery has long been one of the challenging tasks in remote sensing research. Accurately determining age, especially crop age, is essential for plot management, biomass calculations, and carbon sequestration. This research proposes a method for determining the age of LULC using hyper-temporal satellite data. The method is based on the assumption that "the starting point for the age count is when the latest bare land status disappears at any location". To create a geospatial layer (referred to as the BR layer) that can be used to determine the age of any land cover at a specific location, we conditionally stacked such statuses obtained from the analysis of numerous satellite imagery data. The algorithm was tested at two study sites in Thailand, where rubber plantations dominated land use. The study revealed that all the rubber ages determined using BRAH fell accurately within the range of the local government survey data. The manuscript provides a straightforward explanation of the algorithm, including the pseudocode, accuracy assessment, implementations, robustness, and limitations. [ABSTRACT FROM AUTHOR]

Belowground life relies on plant litter, while its linkage to living roots had long been understudied, and remains unknown in the tropics. Here, we analysed the response of 30 soil animal groups to root trenching and litter removal in rainforest and plantations in Sumatra, and found that roots are similarly important to soil fauna as litter. Trenching effects were stronger in soil than in litter, with an overall decrease in animal abundance in rainforest by 42% and in plantations by 30%. Litter removal little affected animals in soil, but decreased the total abundance by 60% in rainforest and rubber plantations but not in oil palm plantations. Litter and root effects on animal group abundances were explained by body size or vertical distribution. Our study quantifies principle carbon pathways in soil food webs under tropical land use, providing the basis for mechanistic modelling and ecosystem‐friendly management of tropical soils. [ABSTRACT FROM AUTHOR]

Human activities, which have interfered with the ecological system, have led to global warming. This has led to the release of carbon stocks into the atmosphere, thereby reducing the function of carbon sinks in places with vegetated land. With increased human activities, vegetated land will soon become non-vegetated. This is because the increased human activities have led to the absorption of higher amounts of carbon in the atmosphere than the required level. Therefore, this study aimed to estimate land cover on carbon stocks in Prabumulih City, South Sumatera Province, Indonesia. The study employed a random field survey using a dynamic system, with the results showing that land cover consisted of oil palm plantations, mixed plantations, grass, swamp shrubs, and rivers. However, the area was dominated by rubber plantations, and as a result, the carbon stocks continued to decline. For instance, in 2008, the level of carbon stock was 2,438.72 Gg and fell to 2,190.85 Gg in 2020, indicating a 4.8% decrease. It is projected that by 2030, the carbon stock in land cover will be 1,988.07 Gg. [ABSTRACT FROM AUTHOR]

Climate change is one of the most critical threats to the human population and other living organisms on Earth. REDD+ is developed as a mechanism to acquire a global fund for addressing climate change, deforestation, and protecting the forest ecosystem while maintaining the livelihood of local communities. As a response to the need for carbon stock measurement at the specific forest and land-use types, this research aimed to estimate the aboveground carbon stock at seven land-use types in KPHP (Forest management unit) Katingan Hulu Central Kalimantan Indonesia. This research was conducted from May to September 2019. The data collected in 91 observation plots included diameter at breast height, total height, and fresh weight of understory vegetation and litter. Using an allometric equation, this research estimated the above-ground carbon stock in trees, understory vegetation, and litter. It was found that AGC varied across different land-use types: secondary peat forest 135.30 Mg C/Ha, secondary forest 212.19 Mg C/Ha, shrub 47.41 Mg C/Ha, oil palm plantation 73.76 Mg C/Ha, rubber plantation 65.56 Mg C/Ha, and forest with rattan 75.98 Mg C/Ha. It was concluded that AGC in KPHP Katingan Hulu varied according to the type of land use system. The forests with less human intervention, such as secondary forests, had higher AGC compared with highly disturbed forests such as shrubs. The findings from this research could help decision-makers to develop the REDD programs to rehabilitate forests and contribute to community development. [ABSTRACT FROM AUTHOR]

Agricultural-land use policies play a crucial role in shaping agroecological landscapes globally. The evidence suggests that some of these policies tend to have undesired feedback/trade-offs, particularly about coastal resource use and conservation planning. The present study explores how agricultural policies influence land use/land cover (LULC) transition patterns in Ghana's Rain Forest Agroecological Zone (RFAZ). Landsat satellite images for 1991, 2008, and 2022 were acquired for the LULC mapping. Change detection and Intensity analysis were used to assess the pattern of land change. Also, documentary research processes were used to review and assess agricultural land use policies. The results showed that before rubber-related policy implementation, oil palm plantation was the dominant LULC type in the 1990 s. In the 1990 s and early 2000 s, there was a conscious government drive to leverage oil palm plantation development. This led to the growth in the size of oil palm plantations within the RFAZ landscape, considering the zone's conducive natural environment. However, between 2008 and 2022, corresponding to the period of the increased promotion of rubber cultivation through the Outgrower project in the RFAZ, rubber plantations became the predominant land use, with an area of 11,763.81 ha in 2008 and 21,611.61 ha in 2022. The results from the LULC mapping and the intensity analysis showed that the Rubber Outgrowers Plantation Project (ROPP) and Norpalm Smallholder Scheme Project (NSSP) have degraded the natural cover through rubber and oil palm cultivation. The authors conclude that landscape dynamics, particularly in rainforest agroecological zones, represent a nexus challenge transforming policy adaptation's discursive context. The study recommends that agriculture and landscape policy/projects must have/take intermediary steps to address the feedback/trade-offs from well-intended initiatives. The study further suggests that management plans and strategies in the RFAZ should be consistent with the strict protection of forest reserves and water bodies. • Agriculture and development policies and interventions drive land use change. • Rubber Outgrowers Plantation Project drives increased rubber plantation coverage. • Conservation objectives are limited in most agricultural land use policies. • The trend of land change coincided with Ghana's population and economic growth. • Integration of geospatial technology and intensity analysis increase understanding of land change. [ABSTRACT FROM AUTHOR]

Currently, many studies have reported that many landslides occur in tea or rubber plantation areas. In these areas, it is important to make a landslide susceptibility map and to take necessary measures to mitigate landslide damage. However, since historical landslide distribution data and land use data are not available, quantitative landslide assessment measurements have not been made in many countries. Therefore, in this study, landslide distribution maps and land use maps are created with worldwide available satellite imagery and Google Earth imagery, and the relationship between landslides and land use is analyzed in Rize, Türkiye. The results show that landslides are 1.75 to 5 times more likely to occur in tea gardens than in forests. It was also found that land use has the highest contribution to landslides among the landslide conditioning factors. The landslide assessment, using a simple landslide detection method and land use classification method with worldwide available data, enabled us to quantitatively reveal the characteristics of landslides. The results of this study reveal that quantitative landslide assessments can be applied in any location, where relatively high resolution satellite imagery and Google Earth imagery, or its alternatives, are available. [ABSTRACT FROM AUTHOR]

Agricultural expansion is among the main threats to biodiversity and functions of tropical ecosystems. It has been shown that conversion of rainforest into plantations erodes biodiversity, but further consequences for food-web structure and energetics of belowground communities remains little explored. We used a unique combination of stable isotope analysis and food-web energetics to analyze in a comprehensive way consequences of the conversion of rainforest into oil palm and rubber plantations on the structure of and channeling of energy through soil animal food webs in Sumatra, Indonesia. Across the animal groups studied, most of the taxa had lower litter-calibrated -13C values in plantations than in rainforests, suggesting that they switched to freshly-fixed plant carbon ('fast' energy channeling) in plantations from the detrital C pathway ('slow' energy channeling) in rainforests. These shifts led to changes in isotopic divergence, dispersion, evenness, and uniqueness. However, earthworms as major detritivores stayed unchanged in their trophic niche and monopolized the detrital pathway in plantations, resulting in similar energetic metrics across land-use systems. Functional diversity metrics of soil food webs were associated with reduced amount of litter, tree density, and species richness in plantations, providing guidelines on how to improve the complexity of the structure of and channeling of energy through soil food webs. Our results highlight the strong restructuring of soil food webs with the conversion of rainforest into plantations threatening soil functioning and ecosystem stability in the long term. [ABSTRACT FROM AUTHOR]

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Soil carbon is one of the most affected variables to land-use change in tropics. The soil carbon flux plays a major role in regulating microbial activities and nutrient distribution in soil. This study aimed to evaluate the soil carbon stock in various land uses at different depths in the hilly terrain of Mizoram, Northeast India. Soil samples at 0-10 cm, 10-20 cm and 20-30 cm soil depths were collected from Rubber plantation (RP), Oil palm plantation (OPP), Teak plantation (TP), Bamboo Forest (BF), 5 years fallow (5YF), 10 years fallow (10YF), Tephrosia candida plantation (TCP), Horticulture garden (HORT), Homegarden (HG) and Natural forest (NF). Soil carbon stock varied significantly (p <0.05) across the land uses and depths. The soil under Tephrosia candida stand had significantly (p <0.05) higher values of C stock (73.66 Mg ha-1) which may be due to high biomass, dense vegetative cover and high C in root exudates. The minimum C stock estimated in Horticulture garden (43.28 Mg ha-1) is probably due to reduced soil organic matter. Soil carbon stock in Homegarden, Teak plantation, Bamboo forest and Rubber plantation ranged from 46.82 Mg ha-1 to 59.34 Mg ha-1 whereas 5 years and 10 years fallow land, Natural forest and Oil palm plantation ranged from 61.35 Mg ha-1 to 73.35 Mg ha-1. The study indicated that the land use change in the mountainous region significantly affected the carbon stock in the soil. A proper land use management strategies to increase the soil organic matter is recommended to enhance the carbon stock in this region. [ABSTRACT FROM AUTHOR]

In this study, we investigated the potential of using decision tree Machine Learning (ML) algorithm and profiles of vegetation and moisture indices extracted from Land Remote-Sensing Satellite (System, Landsat) time series to identify the ages of rubber plantations in Thalang district, Phuket province, southern Thailand. The secondary Land Use and Land Cover (LULC) data and historical imagery from Google EarthTM were used to distinguish plantation boundary and the establishment year of rubber plantation (T0). The inter-annual profiles of spectral indices for each rubber plantation were obtained from 129 Landsat images (summer period from October 1991 to April 2018). The predictors were generated from summary distribution values of spectral indices during summer, including their difference and ratio at two years before to six years T0 for Recursive Partitioning (RP) supervised classification algorithm. Modelling dataset from 'known T0' plantations was divided into the training and testing datasets with a 60:40 ratio. The training model was 30 times repeated training while cross-validation assessment was tested to optimize an appropriated hyperparameter based on F1 score. Then, the best performance training model was applied to both modelling and predicting ('unknown T0' plantations) datasets. The predicted T0 for each plantation was selected based on results aggregation of 100 times repeated prediction. The results show that the RP model with a complexity parameter as 0.01 and the predictors generated only from Normalized Difference Vegetation Index (NDVI) profile acceptable achieves an accuracy of 84.4% and 84.7% for lowland and highland modelling datasets, respectively. The root means squared error (RMSE) of predicted establishment year were 0.83 years at plantation scale. [ABSTRACT FROM AUTHOR]

Monitoring of land use change is crucial for sustainable resource management and development planning. Up-to-date land use change information is important to understand its pattern and identify the drivers. Remote sensing and geographic information system (GIS) have proven as a useful tool to measure and analyze land use changes. Recent advances in remote sensing technology with digital image processing provide unprecedented possibilities for detecting changes in land use over large areas, with less costs and processing time. Thus, the objective of this study was to assess the land use changes in upper Prek Thnot watershed in Cambodia from 2006 until 2018. Geospatial tools such as remote sensing and GIS were used to process and produce land use maps from Landsat 5 TM, Landsat 7 ETM+ and Landsat 8. The post-classification comparison was conducted for analysing the land use changes. Results show forest area was greatly decreased by 1,162.06 km² (33.67%) which was converted to rubber plantation (10.55 km² ), wood shrub (37.65 km2 ), agricultural land (1,099.71 km² ), built-up area (17.76 km² ), barren land (3.65 km² ), and water body (14.69 km² ). Agricultural land increased by 1,258.99 km2 (36.48%), while wood shrub declined by 161.88 km2 (4.69%). Rubber plantation, built-up area, barren land, and water bodies were increased by 10.55 km2 (0.31%), 33.64 km² (0.97%), 4.87 km² (0.14%) and 15.89 km² (0.46%), respectively. The decrease of forest and wood shrub had resulted due to population growth (1.8% from 2008 to 2019) and land conversion for agricultural purposes. Hence, this study may provide vital information for wise sustainable watershed’s land management, especially for further study on the effect of land use change on runoff in this area. [ABSTRACT FROM AUTHOR]

The Songkhram River Basin (SRB), a wetland region and the largest Mekong tributary in the upper northeast region, is undergoing several changes. Understanding the impact of land use change on the hydrological cycle is very important for ensuring sustainable development and management of water resources in any watershed. This research aims to analyse the past land use change, forecast the future land use maps under various scenarios and finally analyse the impact of this change on the water availability of SRB. The analysis of past land use maps reveals a rapid conversion of crops, paddy and natural forest into rubber farms. The land use change model Dyna-CLUE, coupled with the water yield module of InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs Tool) model, was used to evaluate the impact of land use change on the water availability on the basis of different policy scenarios. Land use maps up to the year 2100 were generated on the basis of three future scenarios focused on economy, conservation and agriculture. The results of this study show an increase in water yield under economic scenario as a result of an increase in urban areas and rubber plantations, whereas a small decrease in water yield is seen under conservation scenario. However, no significant changes are seen under agriculture scenario. This study presents the utility of land use model analysis in foreseeing future land use change impact on water availability. Thus, the results serve as a model-backed reference to decision makers to formulate new policies or adjust the existing ones regarding land use in SRB. [ABSTRACT FROM AUTHOR]

Monitoring land use/land cover change at various scales is of foremost importance for the management of natural resources and pivotal to achieve effective environmental governance. The purpose of this study was to classify land use/land cover and to quantify changes in land use/land cover in Luangnamtha district, northern Laos over the past two decades, using remote sensing and Geographic Information System technologies. We used Landsat 5 Thematic Mapper (TM) images from 2000, 2005, 2010 and Landsat 8 Operational Land Imager (OLI) images from 2017. A supervised classification was achieved by applying the maximum likelihood algorithm in the ENVI software. Five land cover classes, namely agriculture, forest, rubber tree, settlement and water were thus identified. The nature and extent of change detected was analyzed on the basis of the land use maps generated for years 2000, 2005, 2010 and 2017. We applied spatial point process theory to analyze spatial relationships between land use classes and with terrain covariables. The overall accuracy of our classifications were 86.8%, 89.3%, 90.4%, and 91.7% for the years 2000, 2005, 2010, and 2017, respectively and the Kappa coefficients were 0.76, 0.85, 0.85, and 0.89, respectively. The results of these classifications indicated that over the 2000 to 2017 period, settled areas increased by 2.35% (5,038 ha), water bodies increased very marginally (0.01% or 20 ha), but that rubber tree cover increased by as much as 7.60% (16,314 ha). During the same period, agricultural land decreased by 0.11% (224 ha) and the forested area shrunk by 9.84% (21,129 ha). Spatial analysis indicates that rubber tree plantations expanded from the lowest part of the landscape, in close spatial association with agricultural land, to increasingly higher locations where it most likely replaced forest. This study confirms that drivers such as government policies for permanent allocation of agricultural land poverty eradication, as well as foreign investments, had a major impact on the expansion of rubber tree plantation in Luangnamtha district from 2000 to 2017. [ABSTRACT FROM AUTHOR]

Land use land cover change (LULC) is a dynamic process, which is largely influenced by anthropogenic effect. In less urbanized area, human activities such as agricultural expansion, timber extraction and infrastructure development, has caused LULC transformation at alarming rate. Understanding of the potential future LULC changes is necessary for town planners and local authorities to formulate and design town planning. Besides that, the projected LULC patterns could also be incorporated into other models to further evaluate the impact of LULC changes on environment, agricultural, ecosystem, water resources and health. This study projected a future LULC scenario of Kelantan, Malaysia, using an integrated GIS CA-Markov model. The model achieved an accuracy of 78.57% when compared with the LULC map of 2008. Built-up area has increased by 111 km2, while forest area has decreased 1532 km2 in the past 15 years. Results showed that the built-up area, oil palm, and rubber plantation are expected to increase to 181.69 km2, 2142.48 km2, and 3076.24 km2, respectively, in 2025. By contrast, forest and paddy area are projected to decrease to 8548.20 km2, and 693.44 km2 respectively. Urban expansion is mainly found in the northern part of the state, while oil palm expansion in the southern part of the state. It was predicted that this pattern will continue in the next thirty years where built-up and agriculture area continued to expand at the stake of forest area. The findings provide useful information for planners in planning for future development and safeguarding the environment. [ABSTRACT FROM AUTHOR]

Changes in land use and improper soil management have led to severe land degradation around the globe through the modification in soil physicochemical and biological processes. This study aimed to assess the soil properties of different land use system types. Soil samples (0-15 cm depth) were collected from five land uses; Rubber Plantation (RP), Oil Palm Plantation (OPP), Bamboo Forest (BF), Fallow Land (FL) and Natural Forest (NF) and analyzed for bulk density, soil texture, soil pH, soil moisture, soil carbon, total nitrogen, ammonium, nitrate, soil microbial biomass carbon, soil respiration. Soil pH was lower than 4.9 in all the sites indicating that the surface soil was highly acidic. Soil organic carbon (SOC) and total nitrogen (TN) values ranged from 2.02% to 2.81% and 0.22% to 0.3% respectively. Soil organic carbon (SOC), total nitrogen (TN) and soil microbial biomass (SMBC) were highly affected by soil moisture. NH4 +-N and NO3 --N ranged from 5.6 mg kg-1 to 10.2 mg kg-1 and 1.15 mg kg-1 to 2.81 mg kg-1 respectively. NF soils showed the maximum soil microbial biomass carbon (SMBC) whereas the minimum was observed in BF with values ranging from 340 mg kg-1 to 345 mg kg-1. Basal respiration was highest in RP (375 mg CO2 m-2 hr-1) and lowest in BF (224 mg CO2 m-2 hr-1). The findings demonstrated significant effect (p<0.05) of land use change on soil nutrient status and organic matter. Findings also indicated that land use change deteriorated native soil physicochemical and biological properties, but that land restoration practices through longer fallow period (>10 years) likely are successful in promoting the recovery of some soil characteristics. [ABSTRACT FROM AUTHOR]

Graphical abstract: Highlights: • A new soil quality index aggregating the set of Biofunctool® indicators was created. • The Biofunctool® index was applied in rubber tree-based cropping systems. • The Biofunctool® index proved to be sensitive to land uses and management practices. • The Biofunctool® index proved to be robust against various pedo-climatic contexts. • The Biofunctool® index allows to characterize a gradient of soil disturbance. Abstract Biofunctool® is a new framework for assessing the impact of land management on soil quality – defined as the capacity of the soil to function. Biofunctool® uses a set of twelve indicators to monitor changes in three key soil functions: carbon transformation, nutrient cycling and structure maintenance (part A). Information from all the indicators is integrated in a Soil Quality Index using multivariate analysis (PCA) weighting. We used Biofunctool® to assess the impact of land use, land use change and agricultural practices on soil quality. The Biofunctool® index was measured for soils in Thailand within rubber plantations, forests and intensive cash crops (cassava and sugar cane). The results demonstrate that the Biofunctool® index provides an aggregated synthetic soil functioning score that is sensitive to land management and is robust in various pedo-climatic contexts. Firstly, the index revealed the impact on soil of land conversion from annual cropping to rubber plantations and ranked the effect on soil with respect to a natural forest reference. Secondly, it showed the positive effect of legume cover-crops on soil functioning. Thirdly, it highlighted a trend of improving soil quality with increasing age of rubber plantations, in contrasted pedo-climatic contexts. It is concluded that the Biofunctool® index is a reliable and relevant descriptor of integrated soil functioning (i.e. soil quality) that could be useful for environmental impact assessment at regional to global scales. [ABSTRACT FROM AUTHOR]

Abstract Rubber farming expansion in Xishuangbanna, in the Upper Mekong region of Southwest China, has resulted in profound land use change and led to the severe degradation of the local environment. This study explores the dynamics of land use change as a result of the rubber boom, examines the factors influencing the heterogeneity in farmers' land allocations for rubber farming, and assesses the implications of this change for the local environment in terms of carbon balances. The analyses use a comprehensive household survey data set of 612 smallholder rubber farmers in Xishuangbanna. The historical data illustrate the trajectory of rubber expansion and land use change over the past three decades. The model of smallholder land allocation for rubber farming suggests its determinants include ethnicity, experience in rubber farming, household wealth, elevation, and several explanatory variables at the village level. A net loss in carbon stocks at the aggregate level was found due to the expansion of rubber plantations. The rubber farming expansion of smallholders outside the natural reserves in Xishuangbanna has led to a carbon loss of approximately 21 Mg/ha/year over the past three decades. The findings complement discussions on the future of the rubber-based land use system and its sustainability in Xishuangbanna and other rubber-growing areas in the Mekong region. Highlights • A household survey data from 612 smallholder rubber farmers in Xishuangbanna Dai Autonomous Prefecture, Southwest China; • Rubber expansion has caused extensive land use change and deforestation; • Land allocation for rubber farming is associated with household characteristics and the policy and project variables; • Rubber expansion outside the natural reserves in Xishuangbanna has led to carbon losses over the past three decades. [ABSTRACT FROM AUTHOR]

Since the early 2000s the Lao government has dramatically increased the number of large‐scale land concessions issued for agribusinesses. While studies have documented the social and environmental impacts of land dispossession, the role of Vietnamese labour on these Vietnamese‐owned rubber plantations has not previously been investigated. Taking a political ecology approach, we situate this study at the intersection between 'land grabbing' studies and work on 'labour geographies'. Most of the remittances generated from Vietnamese working in Laos are used for non‐agricultural purposes, with people purposely choosing to not invest in agriculture in Vietnam. Vietnamese labour on Lao plantations still has significant spatial implications, both in Laos and in Vietnam, including through the norms, formal rules and practices introduced at rubber plantations by Vietnamese workers and management, but also through labour regime changes in Vietnam. In Laos, one of the most significant results has been to make certain spaces less welcoming to Lao labour. This study particularly points to the importance of geopolitics, as the close political relationship between Laos and Vietnam, and the fact that Vietnamese companies and managers are involved, is crucial for understanding the particular nature of the labour geographies associated with Vietnamese rubber plantations in Laos. [ABSTRACT FROM AUTHOR]

Abstract: Conversion of rainforest into agricultural land affects multiple facets of tropical plant diversity. While the effects of tropical land use change and intensification on species diversity are comparatively well studied, the effects on phylogenetic diversity (PD) and structure of plant communities are largely unknown. Furthermore, it is not clear how the loss of native species and addition of alien species collectively affect PD and structure. We investigated the PD and structure of understorey plants; a diverse and ecologically important, yet poorly studied group. We studied four prominent land use systems (tropical lowland rainforest, jungle rubber agroforest, rubber plantations, and oil palm plantations) in the lowlands of Sumatra (Indonesia), a region experiencing dramatic land use changes. Across the four systems, we investigated differences in four metrics of phylogenetic community structure (PD, mean pairwise distance, mean nearest taxon distance, and their abundance‐weighted variants). Our analyses were based on a comprehensive vegetation survey consisting of 32 plots, 1,197 species of vascular plants, and 146,599 plant individuals. Our results showed that forest conversion into agricultural systems leads to a pronounced loss of PD. Furthermore, the standardized effect size of mean pairwise distance indicated a gradual change from clustered to overdispersed phylogenetic community structure with increasing land use intensity from forest over jungle rubber to the monoculture plantations. In most land use systems, the presence or absence of alien plant species did not affect phylogenetic structure. Only in oil palm plantations, removing alien species from the data led to a more overdispersed structure. In conclusion, conserving the PD and structure requires efficient protection of the last remaining rainforests. Synthesis and applications. Forest conversion into agricultural areas negatively affects phylogenetic understorey plant diversity and leads to a shift from clustered to overdispersed phylogenetic community structure. These trends are partly driven by alien species particularly in oil palm plantations. Protecting the remaining rainforests and considering multispecies agroforestry systems in favour of intensive monoculture plantations are thus imperative to conserve phylogenetic plant diversity and community structure. [ABSTRACT FROM AUTHOR]

Abstract: In South‐East Asia, rapid land use changes in recent decades have raised concerns for biodiversity and soil conservation. Weeds provide many ecosystemic services for soil protection and support biodiversity, and could mitigate the negative effects of intensification. We investigated the changes in weed assemblages and weed–soil interactions on a chronosequence from annual crops to mature rubber tree plantations. We sampled five fields for each of four land uses in mountainous northern Thailand (rainfed upland rice, maize, young rubber tree (RT) intercropped with maize, and mature RT). We characterized weed assemblages (abundance, richness) and soil properties (bulk density, water, carbon and nitrogen content). Rice had the most diverse and abundant weed assemblages. Weed assemblages differed between (i) rice, (ii) maize and young RT with maize and (iii) mature RT. Soil water content was the highest in mature RT. Other soil properties varied strongly within and among fields, and did not vary significantly among land uses. Water and nitrogen content increased overall with living soil cover but decreased with weed species richness in mature RT. Such interactions could provide a basis for sustainable weeding practices favourable to soil and biodiversity conservation. [ABSTRACT FROM AUTHOR]

With the current trend of land use/land cover (LULC) change taking place globally, several parts of northeast India are also showing signs of change in LULC pattern leading to forest loss. This study focusses on the expansion of monoculture rubber plantation (Hevea brasiliensis) in selected sub-watersheds in northeast India, and distributed in parts of north Tripura, Mizoram and a major portion in the Karimganj district of Assam. Remote sensing and GIS technique has been used to map and analyse the extent of rubber plantation using temporal IRS LISS III satellite data from 1997 to 2013. It has been observed that rubber plantation increased from 4.47 sq. km to 28.42 sq. km in various parts of the study area. The expansion was more rapid during recent times, i.e. during 2010 to 2013. The plantation took place in dense forest, open forest and degraded forest areas. The spread of the plantation was also observed in one reserved forest located within the study area. There are several instances of negative impacts of rubber plantation expansion in Southeast Asia. Similar expansion of rubber plantation has been observed in northeast India as well. Further spread of rubber plantations in the region needs to be regulated to avoid conversion of dense and reserved forest areas by fostering use of mixed cropping methods instead of rubber monocultures, and by adopting more sustainable land use and management practices. [ABSTRACT FROM AUTHOR]

Expansion of rubber plantations into sub-optimal environments has been a dominating land conversion in continental South-East Asia in the last decade. Regional evaluation of the carbon sequestration potential of rubber trees depends largely on the selection of suitable allometric equations and the biomass-to-carbon conversion factor. Most equations are age-, elevation-, or clone-specific, and their application therefore gives uncertain results at the landscape level with varying age groups, elevation ranges, and clone types. Currently, for rubber-based systems, none of the allometric equations takes environmental factors (e.g. climate, topographic condition, soil properties, and management scheme) into consideration to allow pan-tropical usage. Against this background, 30 rubber trees with a root profile of up to 2 m were destructively harvested and 882 rubber trees were measured non-destructively in 27 plots, covering rotation lengths of 4–35 years, elevation gradients of 621–1127 m, and locally used clone types (GT1, PRIM600, Yunyan77-4) in mountainous South Western China. Allometric equations for aboveground biomass ( AGB ) estimations considering diameter at breast height ( DBH ), tree height ( H ), and wood density were superior to other equations. A simpler model with similar performance ( AGB = 0.0419 DBH 2.316 H 0.478 ) can be used if tree-specific wood density is not available. For belowground biomass ( BGB ) a model using only DBH can provide a robust prediction ( BGB = 0.207 DBH 1.668 ). We also tested goodness of fit for the recently proposed pan-tropical forest model, which includes a bioclimatic factor E , combining indices of temperature and precipitation variability and drought intensity. Prediction of AGB by the model calibrated with the harvested rubber tree biomass and wood density was more accurate than the results produced by the pan-tropical forest model adjusted to local conditions. The relationships between DBH and height and between DBH and biomass were influenced by tapping, therefore biomass and C stock calculations for rubber have to be done using species-specific allometric equations. Based on the analysis of environmental factors acting at the landscape level, we found that above- and belowground carbon stocks were mostly affected by stand age, soil clay content, aspect, and planting density. Increasing planting density to >570 trees per ha according to the regional plantation management strategy had a negative impact on aboveground carbon stock of old rubber plantations. The integration of bioclimatic and regional management factors is a further approach to build widely applicable biomass models for pan-tropical rubber-based systems. The results of this study provide reference for reliable carbon accounting in other rubber-cultivated regions. [ABSTRACT FROM AUTHOR]

The expansion of rubber cultivation in Southeast Asia raises concerns about the integrity of the hydrological cycle. From mainland Asia, high evapotranspiration from rubber plantations was reported. Our study was conducted in the Sumatran lowlands (Indonesia), where rubber is grown by small holders under maritime climate. We assessed patterns of water use with sap flux methods, focusing on influences of tree age and size. We first tested a field measurement scheme in methodological experiments and subsequently applied it to 10 plots in monocultural rubber plantations. Among fully leaved, mature stands, maximum sap flux densities decreased with increasing tree diameter in 14- and 16-year-old plantations, but not in 7- and 8-year-old ones. Consequently, tree water use increased more steeply with increasing diameter in the younger than in the older plantations. In contrast to this, among the same five mature plantations, stand-scale transpiration decreased with increasing mean tree diameter and height. This was due to a negative linear relationship between diameter and stand density. Among seven fully leaved plantations, stand age explained 95% of the site-to-site variability in transpiration. Temporally, rubber transpiration showed pronounced seasonality due to leaf shedding. Transpiration in our study was substantially lower than in rubber plantations in mainland Asia; reasons include differences in methods, management, and climate. In Sumatra, rubber may be ecohydrologically less concerning than, for example, oil palm plantations, due to low transpiration and periodical leaf shedding. Our study endorses the importance of considering age, management, climate, and species in ecohydrological assessments of tropical plantation landscapes. [ABSTRACT FROM AUTHOR]

This paper describes changes in the pattern of land use in two riverine districts of Nakhon Phanom Province between 2006 and 2010. A great deal of land use change occurred in these five years. In Mueang District, about 12.1% of the area (9,477 ha) had a different use in 2010 from that in 2006. In That Phanom District the magnitude of change was even greater, with about 27.3% of the area (9,326 ha) changing use between 2006 and 2010. Much of the land use change in both districts resulted from the conversion of natural forests, orchards, and rice paddies into rubber plantations. At the same time, rapid urbanization led to the conversion of large areas of farmland into housing estates in the peri-urban zone around Nakhon Phanom City and, to a lesser extent, around That Phanom district town. Most of these land use changes are reducing overall agroecological diversity. Several factors have influenced these land use changes, including lack of secure land titles, urban growth, and changes in the costs and benefits of growing different crops. [ABSTRACT FROM AUTHOR]

Determining the age of rubber tree plantations (Hevea brasiliensis) is of great interest to plantation managers and land-use decision makers as it enables, among others, reliable forecasts of resource availability. The acquisition of age information with field campaigns, however, is time consuming, laborious and expensive. We present an approach that facilitates rapid assessment of rubber plantation age at regional scales applying very dense Landsat times series (LTS) satellite data over China's second largest rubber planting area – Xishuangbanna. We aggregated 270 Landsat TM and ETM + surface reflectance images into annual best-available-pixel composites of minimum Normalized Difference Moisture Index ( NDMI ). The annual composites were classified into vegetated and non-vegetated pixels applying a global NDMI threshold of 0. As it is common practice in Xishuangbanna to clear the land before a new plantation is established, the last year in which a pixel located in a rubber plantation, was classified as non-vegetated, was recorded as the year of plantation establishment. The resultant plantation age map was validated using a stratified random sample of 184 data points, collected by visual interpretation of historical Landsat data. A Root Mean Square Error (RMSE) of 2.5 years was achieved. We estimate that in 2015 50% of Xishuangbanna's rubber plantations had an age suitable for latex tapping (8–25 years), 27% were too young to be tapped (< 8 years) and 24% had already reached an age of reduced latex productivity (> 25 years) and will be presumably harvested for wood in the near future. The proposed technique enables acquisitions of accurate rubber plantation age information from Landsat time series and NDMI over large areas with the potential of providing insights into land cover dynamics and allowing for the development of improved management strategies and local decision support activities. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to examine the impact of farmers’ risk perceptions regarding rubber farming on their land use choices, including rubber specialization and crop diversification.Design/methodology/approach A cross-sectional survey data of some 600 smallholder rubber farmers in Xishuangbanna in Southwest China is employed. This paper develops a general conceptual framework that incorporates a subjective risk item into a model of farmers’ land use choices, thereby developing four econometric models to estimate the role of risk perceptions, and applies instrumental variables to control for the endogeneity of risk perceptions.Findings The results demonstrate that risk perceptions play an important role in smallholders’ decision-making regarding land use strategies to address potential risks in rubber farming. Smallholders with higher risk perceptions specialize in rubber farming less often and are more likely to diversify their land use, thereby contributing to local environmental conservation in terms of agrobiodiversity. The land use choices of smallholder rubber farmers are also associated with ethnicity, household wealth, off-farm employment, land tenure status, altitude and rubber farming experience.Originality/value This study contributes to a better understanding of the implications of farmers’ risk perceptions and shows entry points for improving the sustainability of rubber-based land use systems. [ABSTRACT FROM AUTHOR]

Land-use change in tropical peatland potentially results in a large amount of carbon dioxide (CO 2 ) emissions owing to drainage, which lowers groundwater level (GWL) and consequently enhances oxidative peat decomposition. However, field information on carbon balance is lacking for rubber plantations, which are expanding into Indonesia's peatlands. To assess soil CO 2 emissions from an eight-year-old rubber plantation established on peat after compaction, soil CO 2 efflux was measured monthly using a closed chamber system from December 2014 to December 2015, in which a strong El Niño event occurred, and consequently GWL lowered deeply. Total soil respiration (SR) and oxidative peat decomposition (PD) were separately quantified by trenching. In addition, peat surface elevation was measured to determine annual subsidence along with GWL. With GWL, SR showed a negative logarithmic relationship ( p < 0.01), whereas PD showed a strong negative linearity ( p < 0.001). Using the significant relationships, annual SR and PD were calculated from hourly GWL data to be 3293 ± 1039 and 1408 ± 214 g C m − 2 yr − 1 (mean ± 1 standard deviation), respectively. PD accounted for 43% of SR on an annual basis. SR showed no significant difference between near and far positions from rubber trees ( p > 0.05). Peat surface elevation varied seasonally in almost parallel with GWL. After correcting for GWL difference, annual total subsidence was determined at 5.64 ± 3.20 and 5.96 ± 0.43 cm yr − 1 outside and inside the trenching, respectively. Annual subsidence only through peat oxidation that was calculated from the annual PD, peat bulk density and peat carbon content was 1.50 cm yr − 1 . As a result, oxidative peat decomposition accounted for 25% of total subsidence (5.96 cm yr − 1 ) on average on an annual basis. The contribution of peat oxidation was lower than those of previous studies probably because of compaction through land preparation. [ABSTRACT FROM AUTHOR]

• A meta-analysis to test rubber stand age and altitude effects on soil properties. • Forest-to-rubber conversion significantly reduced SOC pools by 24%. • Rubber monoculture-to-intercropping significantly increased SOC pools by 6%. • Improvement of intercropping occurred in 0–20 cm soil and at 500–800 m altitude. The rapid expansion of rubber plantations may have greatly influenced the carbon stocks of the ecosystem, with potential impacts on mitigating climate change and future carbon fluxes. Therefore, soil carbon pools and other properties must be reliably estimated after rubber-based land cover transitions. The aim of this meta-analysis is to understand how various land use changes based on rubber plantations affect soil physicochemical properties, especially soil organic carbon (SOC) pools. This study focuses on three land use changes: (1) forest-to-rubber conversion; (2) rubber monoculture vs. intercropping; and (3) the age and altitude of the rubber stand over a chronosequence in rubber plots. Results showed that the conversion of forest to rubber plantation significantly reduced the SOC, microbial carbon (MBC), total nitrogen (TN) and total magnesium pools by 24%, 35%, 13% and 94% respectively, whereas rubber intercropping with different crops profoundly increased the SOC and MBC pools by 6% and 24% on average, respectively. The improvement of rubber intercropping on SOC and properties mainly occurred in the surface soil at 0–20 cm and at altitudes of 500–800 m, but these effects were diminished in the subsurface soil at 20–60 cm and at altitudes higher than 800 m. Rubber intercropping plantations can significantly alleviate soil acidification. Changes in the response ratio of SOC were closely related to the variations in soil clay, bulk density, and C/N ratio. These results suggest that rubber-based land use management policies should promote intercropping plantations, especially those with woody plants, and the altitude of rubber planting should be manipulated to minimize the loss of soil C, N, and other nutrients. [ABSTRACT FROM AUTHOR]

Research on the spatial patterns of human-wildlife conflict is fundamental to understanding the mechanisms underlying it and to identifying opportunities for mitigation. In the state of Xishuangbanna, containing China’s largest tropical forest, an imbalance between nature conservation and economic development has led to increasing conflicts between humans and Asian elephants (Elephas maximus), as both elephant numbers and conversion of habitable land to rubber plantations have increased over the last several decades. We analyzed government data on the compensation costs of elephant-caused damage in Xishuangbanna between 2008 and 2012 to understand the spatial and temporal patterns of conflict, in terms of their occurrence, frequency and distribution. More than 18,261 incidents were reported, including episodes involving damage to rubber trees (n = 10,999), damage to crops such as paddy, upland rice, corn, bananas and sugarcane (n = 11,020), property loss (n = 689) and attacks on humans (n = 19). The conflict data reconfirmed the presence of elephants in areas which have lacked records since the late 1990s. Zero Altered Negative Binomial models revealed that the risk of damage to crops and plantations increased with proximity to protected areas, increasing distance from roads, and lower settlement density. The patterns were constant across seasons and types of crop damaged. Damage to rubber trees was essentially incidental as elephants searched for crops to eat. A predictive map of risks revealed hotspots of conflict within and around protected areas, the last refuges for elephants in the region, and along habitat corridors connecting them. Additionally, we analyzed how mitigation efforts can best diminish the risk of conflict while minimizing financial costs and adverse biological impacts. Our analytical approach can be adopted, adjusted and expanded to other areas with historical records of human-wildlife conflict. [ABSTRACT FROM AUTHOR]

The expansion of rubber plantations ( Hevea brasiliensis Müll. Arg) is a major driving force for deforestation and forest degradation in mountainous South-East Asia. In China, the unclear distinction between natural forest and commercial plantations has permitted the expansion of rubber into protected forest areas of nature reserves. However, the impact of such land-use changes on landscape carbon balances within nature reserves has rarely been investigated. We selected the Naban River Watershed National Nature Reserve (NRWNNR) in Xishuangbanna, China as a case study area and evaluated carbon stocks using the Rapid Carbon Stock Appraisal (RaCSA) method based on tree, plot, land use and landscape assessments, integrating field sampling with remote sensing and GIS technology. Six dominant land use systems were surveyed: lowland forest (<800 m above sea level), highland forest (>800 m a.s.l.), lowland rubber, highland rubber, bush and grassland and agricultural crops. Land use type-specific time-averaged carbon stocks ( C ta ) were calculated based on total above ground biomass (AGB). Soil organic carbon (surface 30 cm) and below ground biomass were measured, but not included in C ta calculations due to large uncertainties unrelated to land use change. The C ta of lowland and highland rubber plantations were 58 Mg C ha −1 and 28 Mg C ha −1 respectively, showing larger carbon sequestration potential than nonforest land use types (agricultural crops, bush and grassland) but much lower than C ta of natural forest (156–185 Mg C ha −1 ). Sensitivity analysis of C ta variability showed that forest C stocks have the largest influence on landscape carbon balance. Time series analysis of land-use and land-cover maps (1989, 2007, 2012) demonstrated that during 23 years, the whole landscape of the nature reserve (26,574 ha) gained 0.644 Tg C. Despite rubber expansion, biosphere zoning strategy (i.e. experimental, buffer, core zones), and reforestation activities conducted in NRWNNR were able to enhance the carbon stocks. [ABSTRACT FROM AUTHOR]

Tropical lowland rainforests are increasingly threatened by the expansion of agriculture and the extraction of natural resources. In Jambi Province, Indonesia, the interdisciplinary EFForTS project focuses on the ecological and socio-economic dimensions of rainforest conversion to jungle rubber agroforests and monoculture plantations of rubber and oil palm. Our data confirm that rainforest transformation and land use intensification lead to substantial losses in biodiversity and related ecosystem functions, such as decreased above- and below-ground carbon stocks. Owing to rapid step-wise transformation from forests to agroforests to monoculture plantations and renewal of each plantation type every few decades, the converted land use systems are continuously dynamic, thus hampering the adaptation of animal and plant communities. On the other hand, agricultural rainforest transformation systems provide increased income and access to education, especially for migrant smallholders. Jungle rubber and rubber monocultures are associated with higher financial land productivity but lower financial labour productivity compared to oil palm, which influences crop choice: smallholders that are labour-scarce would prefer oil palm while land-scarce smallholders would prefer rubber. Collecting long-term data in an interdisciplinary context enables us to provide decision-makers and stakeholders with scientific insights to facilitate the reconciliation between economic interests and ecological sustainability in tropical agricultural landscapes. [ABSTRACT FROM AUTHOR]

Copyright of International Forestry Review is the property of Commonwealth Forestry Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tropical landscapes are not only rapidly transformed by ongoing land-use change, but are additionally confronted by increasing seasonal climate variation. There is an increasing demand for studies analyzing the effects and feedbacks on ecosystem functioning of large-scale conversions of tropical natural forest into intensively managed cash crop agriculture. We analyzed the seasonality of aboveground litterfall, fine root litter production, and aboveground woody biomass production (ANPP) in natural lowland forests, rubber agroforests under natural tree cover ('jungle rubber'), rubber and oil palm monocultures along a forest-to-agriculture transformation gradient in Sumatra. We hypothesized that the temporal fluctuation of litter production increases with increasing land-use intensity, while the associated nutrient fluxes and nutrient use efficiency (NUE) decrease. Indeed, the seasonal variation of aboveground litter production and ANPP increased from the natural forest to the plantations, while aboveground litterfall generally decreased. Nutrient return through aboveground litter was mostly highest in the natural forest; however, it was significantly lower only in rubber plantations. NUE of N, P and K was lowest in the oil palm plantations, with natural forest and the rubber systems showing comparably high values. Root litter production was generally lower than leaf litter production in all systems, while the root-to-leaf ratio of litter C flux increased along the land-use intensity gradient. Our results suggest that nutrient and C cycles are more directly affected by climate seasonality in species-poor agricultural systems than in species-rich forests, and therefore might be more susceptible to inter-annual climate fluctuation and climate change. [ABSTRACT FROM AUTHOR]

The article analyzes the forest devolution in upland central Vietnam. Topics mentioned include the institutional changes in the use of forest and forestland, measurement of direct benefits from using forestland for industrial crop, afforestation, and rubber plantation local people, as well as the allocation of forestland to various cultivation models.

Copyright of International Forestry Review is the property of Commonwealth Forestry Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasingly, international agreements, treaties, and conventions address tropical deforestation and specific causes of rainforest transformation. Such international regimes may aim to conserve natural forests or to support the exploitation of lands for a particular purpose, e.g. agricultural commodities. This paper’s goal is to map the international regime complex for rainforest transformation by identifying those global and regional regimes that are relevant for tropical rainforest transformation systems in Indonesia. The relevance of international regimes for rainforest transformation is assessed based on a novel methodology using two criteria: First, international regimes may be relevant in Indonesia because the core problem they address exists in Indonesia (problem dimension). Second, specific international regimes may be made relevant by the actions of specific actors and their coalitions in pursuit of their interests (actor dimension). To achieve the study’s goals we used (1) content analysis of international policy documents and treaty texts, (2) expert interviews with key informants in Indonesia, and (3) own field observations in current Indonesian land use politics. The results indicate that regimes dealing with biological diversity, climate change, trade in endangered species, wetland management, international tropical trade, illegal logging, Southeast Asian (ASEAN) forest and environment, the Asia Pacific free trade, and the southeast Asian rubber trade regime are relevant in both the problem and actor dimensions. The regimes concerned with desertification and international forestry research are relevant only in the actor dimension. In contrast, the following regimes are relevant only in the problem dimension: indigenous rights, forest certification, palm oil certification, agroforestry certification, and international rubber trade. We discuss our results considering global and regional regimes relevant to Indonesian rainforest transformation systems. We conclude that regimes relevant solely due to the engagement of domestic actors and not in respect of the problem dimension are unlikely to maintain their relevance in the long term. In the short term, however, they have the potential for creating substantial political benefits for the actors using them. In contrast, regimes with high problem relevance but low actor backing are unlikely to even enter the political agenda, and therefore will have only limited impact. This suggests that future research should consider that, whilst relevance in the problem dimension is necessary to establish regime influence, it alone does not suffice. We can expect global and regional regimes to have an influence only when powerful actors back them in their agenda setting, domestic policy formulation and actual implementation. [ABSTRACT FROM AUTHOR]

During the last half century, rubber plantations have spread widely and rapidly in Xishuangbanna, China. This study characterizes the process of expansion in smallholder rubber farming and the subsequent changes in upland use through an in-depth case study of two Dai villages in Xishuangbanna. The results show that the area of smallholder rubber farming has increased in the study villages, as observed in other parts of Xishuangbanna. The evolution of forest policy governing the community forest in Xishuangbanna is divided into three periods: the initial, transition and strict control periods. In the initial period, customary law governed the community forest, and planting rubber was a risky choice in the eyes of villagers, while the government-provided subsidy and techniques spurred the conversion from subsistence cropping to rubber gardens. In the transition period, forest governance by the government began to intervene in the land use customs. Villagers recognized the profitability of rubber farming, and they had chance to convert community forests into rubber gardens because the forest policy was ambiguous. The expansion of rubber farming had a substantial impact on forest cover in the transition period, while the village communities conserved a part of community forest because they have a stake in conserving forest resource. In the strict control period, the government initiated a strict control, especially targeting logging. Consequently, even though there remains a strong demand for the expansion of rubber farms, the new lands chosen for rubber farms were areas in which other crops were already established. In conclusion, strict government governance with a clear objective and support from local communities has been sufficient to control the encroachment of smallholder rubber farming into natural forests in Xishuangbanna. [ABSTRACT FROM AUTHOR]

Rubber agroforests in the mostly deforested lowlands of Sumatra, Indonesia are threatened by conversion into monoculture rubber or oil palm plantations. We applied an agent-based model to explore the potential effectiveness of a payment for ecosystem services (PES) design through a biodiversity rich rubber eco-certification scheme. We integrated conditionality, where compliance with biodiversity performance indicators is prerequisite for awarding incentives. We compared a PES policy scenario to ‘business-as-usual’ and ‘subsidized land use change’ scenarios to explore potential trade-offs between ecosystem services delivery and rural income. Results indicated that a rubber agroforest eco-certification scheme could reduce carbon emissions and species loss better than alternative scenarios. However, the suggested premiums were too low to compete with income from other land uses. Nevertheless, integrating our understanding of household agent behavior through a spatially explicit and agent-specific assessment of the trade-offs can help refine the design of conservation initiatives such as PES. [ABSTRACT FROM AUTHOR]

The study the effect of land use on soil carbon is importantly for the future management of greenhouse gases and climate change, and soil carbon budget is one activity mention of the United Nations Framework Convention on Climate Change (UNFCCC) for decreasing effect from climate change. Previous studies based on field observations have provided direct information about soil carbon storage and fluxes at specific sites, but soil carbon is highly dynamic in space and time and that is driven by complex combinations of hydrology, soil vegetation and management condition. The observation results was soil carbon higher in mixed deciduous forest 17,472.30 Kg C ha-1 than para rubber plantation 8,304.52 Kg C ha-1 at depth 0-5 cm and at depth 5-20 cm 8,304.52 Kg C ha-1 and 6,776.65, respectively. The DNDC model has shown that it can perform well in its representation of the effects of both land uses change in this study area. Simulation results showed significant loss of soil carbon from system under both land use types and eight scenarios of land use change from mixed deciduous forest to para rubber plantation and para rubber tree change to mixed deciduous forest. The annual 50 year soil carbon was 17,960 and 8,300 C ha-1 yr-1 for mixed deciduous forest and para rubber plantation, respectively. The simulated soil carbon under land uses change scenarios. The result for soil carbon content in three scenarios for mixed deciduous forest change to para rubber plantation scenarios. The soil carbon decrease in all scenarios and the mean decrease highest of litter carbon in MDF 10 Year to Para rubber 40 Year scenario was 8,770.42 C ha-1 yr-1 or 49.79% and mean lowest of soil carbon MDF 40 Year to Para rubber 10 Year scenario was 4,700.47 ha-1 yr-1 or 26.68 %. The result for soil carbon content in three scenarios for mixed deciduous forest change to para rubber plantation scenarios. The mean soil carbon and decrease highest of litter carbon in para rubber plantation 10 year change to mixed deciduous forest 40 year was 6931.22 C ha-1 yr-1 or 45.57% and mean lowest of soil carbon para rubber plantation 40 year change to mixed deciduous forest 10 year was 3452.57 C ha-1 yr-1 or 22.70%. [ABSTRACT FROM AUTHOR]

Growing global demand for natural rubber is driving deforestation due to the expansion of rubber plantations, with consequences for biodiversity, carbon storage, and local communities. There has been little attention given to these issues in Sri Lanka, where rubber production is central to economic growth. Although private initiatives and government regulations aim to reduce deforestation associated with these plantations, it is unclear if these measures effectively protect forests or limit associated risks in the supply chains of companies purchasing Sri Lankan rubber. This paper uses the TRACAST methodological framework and remote sensing to track natural rubber supply chains from Sri Lanka to the U.S and to identify hidden deforestation risks resulting from this trade. We estimate 196 km2 of forest were converted into rubber plantations between 2006 and 2016, including protected forests located in an emerging rubber frontier in southeast Sri Lanka. Our analysis identifies rubber traders and multinational tire manufacturers as key actors that hinder the traceability of rubber back to the plantations. This opacity increases the potential for unsustainably produced rubber to enter global supply chains of transnational corporations such as Loadstar (Michelin) and Nike. Most of these corporations have sustainable procurement policies, but the effectiveness of these policies is compromised by the lack of supply chain transparency. Integrating public and private sector management through inclusive multi-stakeholder initiatives and multi-level land use governance can help overcome these hurdles, prevent future deforestation, and assist Sri Lanka in moving towards more sustainable rubber production. • Deforestation in Sri Lanka due to rubber plantations is understudied. • Remote sensing indicates 196 km2 of forest became rubber plantations (2006–2016). • Exports of rubber from Sri Lanka is flowing into global corporate supply chain. • These rubbers flows are a risk for corporate sustainability. • Better public and private governance can curb deforestation from rubber plantations. [ABSTRACT FROM AUTHOR]

The catchment of Bera Lake in Pahang State, Peninsular Malaysia has experienced severe land use changes since 1972 with some 340km2 (out of a total area of ∼600km2) having been converted to oil palm and rubber plantations and in some places, newly cleared for monoculture. The proportional model using the 137Cs radionuclide was recognized as being the most suitable conversion model for estimating soil redistribution in the catchment as the deforested land has been cultivated once in a medium-term range of 30–40 years. Thirty-five bulk core soil samples were taken to a depth of 25cm in areas of different land use and known dates of tillage commencement in the catchment. Ten bulk core samples were also collected in the bottom sediments of wetlands and open waters to estimate accumulation rates in these sink areas. Individual land development districts with known elapsed times from start of tillage allowed determination of soil redistribution rates and preparation of a soil redistribution map. A mean soil erosion rate of 915±345th−1 y−1 was determined in areas of cleared land, whereas rates of 117±36, and 70±35th−1 y−1, were determined in areas of developing, and developed, oil palm and rubber plantations, respectively. The overall accumulation rate of eroded soils within the wetlands and open waters was determined to be 1.025cmy−1 since 1995. The Bera Lake catchment soil redistribution map is the first attempt in Malaysia to map soil redistribution using the 137Cs technique on a catchment scale. The soil redistribution map will provide good guidelines for future soil conservation practices and sustainable land use programs. [ABSTRACT FROM AUTHOR]

The response of insects to monoculture plantations has mainly proceeded at the expense of natural forest areas, and is an outstanding and important issue in ecology and conservation biology, with pollination services declined around the world. In this study, species richness and distribution of hoverfly and wild bee communities were investigated in a changing tropical landscape in southern Yunnan, south-west China by Malaise traps periodically from 2008 to 2009. Species were recorded from the traditional land use types (natural forest, grassland, shrubland and rice field fallows), and from recently established rubber plantations of different ages. Hoverflies (total 53 species) were most common in young successional stages of vegetation, including rice field fallow and shrubland. Species richness was highest in rice field fallows and lowest in forests and showed a highly significant relationship with the number of forb species and ground vegetation cover. In contrast, the highest richness of wild bees (total 44 species) was recorded from the natural forest sites, which showed a discrete bee community composition compared to the remaining habitat types. There was no significant relationship between the bee species richness and the environmental variables, including the numbers of different plant life forms, coverage of canopy and ground vegetation, successional age of vegetation and land use type. At the landscape scale, open land use systems, including young rubber plantations, are assumed to increase the species richness of hoverflies; however, this might decrease wild bee diversity. The present land use change by rubber cultivation can be expected to have negative impacts on the native wild bee communities. [ABSTRACT FROM AUTHOR]

Over the past thirty years, Xishuangbanna in Southwestern China has seen dramatic changes in land use where large areas of tropical forest and fallow land have been converted to rubber and tea plantations. In this study we evaluated the effects of land use and slope on soil properties in seven common disturbed and undisturbed land-types. Results indicated that all soils were acidic, with pH values significantly higher in the 3- and 28-year-old rubber plantations. The tropical forests had the lowest bulk densities, especially significantly lower from the top 10 cm of soil, and highest soil organic matter concentrations. Soil moisture content at topsoil was highest in the mature rubber plantation. Soils in the tropical forests and abandoned cultivated land had inorganic N (IN) concentrations approximately equal in NH-N and NO-N. However, soil IN pools were dominated by NH-N in the rubber and tea plantations. This trend suggests that conversion of tropical forest to rubber and tea plantations increases NH-N concentration and decreases NO-N concentration, with the most pronounced effect in plantations that are more frequently fertilized. Soil moisture content, IN, NH-N and NO-N concentrations within all sites were higher in the rainy season than in the dry season. Significant differences in the soil moisture content, and IN, NH-N and NO-N concentration was detected for both land uses and sampling season effects, as well as interactions. Higher concentrations of NH-N were measured at the upper slopes of all sites, but NO-N concentrations were highest at the lower slope in the rubber plantations and lowest at the lower slopes at all other. Thus, the conversion of tropical forests to rubber and tea plantations can have a profound effect on soil NH-N and NO-N concentrations. Options for improved soil management in plantations are discussed. [ABSTRACT FROM AUTHOR]

Policy makers across the tropics propose that carbon finance could provide incentives for forest frontier communities to transition away from swidden agriculture (slash-and-burn or shifting cultivation) to other systems that potentially reduce emissions and/or increase carbon sequestration. However, there is little certainty regarding the carbon outcomes of many key land-use transitions at the center of current policy debates. Our meta-analysis of over 250 studies reporting above- and below-ground carbon estimates for different land-use types indicates great uncertainty in the net total ecosystem carbon changes that can be expected from many transitions, including the replacement of various types of swidden agriculture with oil palm, rubber, or some other types of agroforestry systems. These transitions are underway throughout Southeast Asia, and are at the heart of REDD+ debates. Exceptions of unambiguous carbon outcomes are the abandonment of any type of agriculture to allow forest regeneration (a certain positive carbon outcome) and expansion of agriculture into mature forest (a certain negative carbon outcome). With respect to swiddening, our meta-analysis supports a reassessment of policies that encourage land-cover conversion away from these [especially long-fallow] systems to other more cash-crop-oriented systems producing ambiguous carbon stock changes - including oil palm and rubber. In some instances, lengthening fallow periods of an existing swidden system may produce substantial carbon benefits, as would conversion from intensely cultivated lands to high-biomass plantations and some other types of agroforestry. More field studies are needed to provide better data of above- and below-ground carbon stocks before informed recommendations or policy decisions can be made regarding which land-use regimes optimize or increase carbon sequestration. As some transitions may negatively impact other ecosystem services, food security, and local livelihoods, the entire carbon and noncarbon benefit stream should also be taken into account before prescribing transitions with ambiguous carbon benefits. [ABSTRACT FROM AUTHOR]

Carabid beetles (Coleoptera: Carabidae) have widely been used to assess biodiversity values of different habitats in cultivated landscapes, but rarely in the humid tropics. This study aimed to investigate effects of land use change on the carabid assemblages in a tributary valley of the Mekong River in tropical southern Yunnan, China. The study area includes habitats of traditional land use systems (rice production and shifting cultivation successions) and was dominated by natural forests until about 30 years ago. Since then, large areas of forest have been, and still are, successively transformed into commercial rubber monoculture plantations. In total, 102 species of Carabidae (including Cicindelinae) were recorded from 13 sites over different seasons, using pitfall traps, Malaise traps and aerial collectors in trees. Cluster analysis and indicator species analysis showed that three types of habitat (rice field fallows, early natural successions and natural forest) possess a degree of uniqueness in species composition. Non-metric multidimensional scaling revealed that the environmental factors explaining 80% of the total variation in carabid assemblage composition are the degree of vegetational openness of a habitat and its plant species diversity. Rice field fallows had significantly higher numbers of species and individuals than any other type of habitat and are probably dominated by species originating from other regions. Carabid assemblages of young rubber plantations (5 and 8 years) were quantitatively similar to those of forests, but without species of significant indicator value. With increasing plantation age (20 and 40 years), the number of carabid species decreased. Increasing age and a further spatial expansion of rubber plantations at the expense of forest areas will have negative impacts on the native forest carabid assemblages with strongest effects on forest specialists and rare species. [ABSTRACT FROM AUTHOR]

Abstract: Expanding global and regional markets are driving the conversion of traditional subsistence agricultural and occupied non-agricultural lands to commercial-agricultural purposes. In many parts of mainland Southeast Asia rubber plantations are expanding rapidly into areas where the crop was not historically found. Over the last several decades more than one million hectares of land have been converted to rubber trees in areas of China, Laos, Thailand, Vietnam, Cambodia and Myanmar, where rubber trees were not traditionally grown. This expansion of rubber plantations has replaced ecologically important secondary forests and traditionally managed swidden fields and influenced local energy, water and carbon fluxes. Accurate and up-to-date monitoring and mapping of rubber tree growth is critical to understanding the implications of this changing ecosystem. Discriminating rubber trees from second-growth forests and fallow land has proven challenging. Previous experiments using machine-learning approaches with hard classifications on remotely sensed data, when faced with the realities of a heterogeneous plant-life mixture and high intra-class variance, have tended to overestimate the areas of rubber tree growth. Our current research sought to: 1) to investigate the potential of using a Mahalanobis typicality model to deal with mixed pixels; and 2) to explore the potential for combining MOderate Resolution Imaging Spectroradiometer (MODIS) imagery with sub-national statistical data on rubber tree areas to map the distribution of rubber tree growth across this mainland Southeast Asia landscape. Our study used time-series MODIS Terra 16-day composite 250 m Normalized Difference Vegetation Index (NDVI) products (MOD13Q1) acquired between March 2009 and May 2010. We used the Mahalanobis typicality method to identify pixels where rubber tree growth had the highest probability of occurring and sub-national statistical data on rubber tree growth to quantify the number of pixels of rubber tree growth mapped per administrative unit. We used Relative Operating Characteristic (ROC) and error matrix analysis, respectively, to assess the viability of Mahalanobis typicalities and to validate classification accuracy. High ROC values, over 0.8, were achieved with the Mahalanobis typicality images of both mature and young rubber trees. The proposed method greatly reduced the commission errors for the two types of rubber tree growth to 1.9% and 2.8%, respectively (corresponding to user’s accuracies of 98.1% and 97.2%, respectively). Results indicate that integrating Mahalanobis typicalities with MODIS time-series NDVI data and sub-national statistics can successfully overcome the earlier overestimation problem. [Copyright &y& Elsevier]