Cryptic destruction of India's native forests

Vietnam’s forest cover changes 2005–2016: Veering from transition to (yet more) transaction?

This study basically focuses on an overview of the dynamics of change of forest cover in India using data from the World Bank from 1990 to 2021. This research involves the quantification and analysis of trends in forest cover across different states and classes of forest types, drivers of change, and, finally, assessing the impact of conservation policy. Using World Bank reports, we adopted statistical modeling tools to assess the changes in forest cover, density, and composition. The study integrated other databases on the determinants of socioeconomics, climatic variables, and policy implementations to get an insight into the complex interplay of human activities, environmental conditions, and forest ecosystems. The results bring out a more nuanced picture of changes in forest cover across the country: Presently, some states show significant gains due to successful state policy related to afforestation, capsule restoration programs, and strict protection being followed, while in others, there were persistent pressures of deforestation, linked to urbanization, agricultural expansion, and infrastructure development. Among the various forest types, the denser forests were relatively more resilient to change compared to open and scrub forests, which showed a higher level of vulnerability to anthropogenic and-climate-induced pressures. Policy impact analysis results suggest that while the forest management at community level and the intensity of site-specific conservation interventions yielded effective results, there is also concern regarding qualitative maintenance of forests and biodiversity amidst quantitative increase in forest covers. The value that this research brings is in adding more scope to understanding India’s forest dynamics and in offering, through evidence-based recommendations, policy tools for policymakers. Specific strategies and appropriate management must be a priority in regional needs, perspective monitoring, and integrated land-use planning that can ensure sustainability in forest management and conservation in the face of growing environmental challenges.

Assessing effects of the Returning Farmland to Forest Program on vegetation cover changes at multiple spatial scales: The case of northwest Yunnan, China

Both local and regional habitat characteristics influence species richness and community structure. The scale at which communities are studied, however, affects the detection of relationships between habitat characteristics and patterns of habitat selection, species diversity, and species composition, and may obscure observation of differences in how species perceive the scale of environmental variation. To determine how environmental variation at different scales is related to species occurrence and richness, I analyze mist net sampling data on several guilds of forest understory birds. Bird capture, vegetation, and physical environment data come from 23 0.5-ha study sites in primary and secondary forest in Amazonian Ecuador. The percentages of primary forest within concentric circles around each site form forest imbeddedness measures (FIMs), which are evaluated using satellite imagery. Variation in FIM size represents different measurement scales for determining forest cover. Primary forest cover is also analyzed in successively larger tori surrounding sites and is used, after variable reduction with Principal Components Analysis, to summarize variation in forest cover around sites. Linear regression, surface trend analysis, and ordination help to quantify how variation in guild composition and species richness is explained by forest cover, vegetation structure, and physical environment. Species composition is related to variation in primary forest cover, primarily within 200-600 m of study sites. Canonical Correspondence Analysis (CCA) indicates that nectarivores, shrub-layer frugivores, and ant-following birds are captured in areas with relatively low primary forest cover. In contrast, shrub-layer insectivores, shrub-layer omnivores, and birds probing dead foliage for large insects tend to be captured in areas of relatively high primary forest cover. The species richness of insect gleaners, ant followers, and omnivores is statistically related to the percent cover of primary forest within hundreds of meters from the study sites. This suggests that some mechanisms that influence guild composition act over substantial distances. Nonetheless, the small radii of FIMs related to the species richness of dead-leaf probers suggests that local conditions and variation in forest cover over short (<200 m) distances directly or indirectly influence species richness of some primary forest birds. The significant relationship between temperature variation among capture sites and species richness of ant-following birds suggests that these species choose among habitats in a temperature range at which physiological constraints operate, either directly on the birds themselves or on the ants they follow. Species richness within the nectarivores, in contrast, shows no relationship with large-scale variation in primary forest cover. The radius of the FIM most closely associated with species richness differs among guilds, which suggests variation in the scale at which forest cover is associated with guild structure, as well as variation in the strength of the association. Differences in the scale of relationships between environment and species richness among guilds suggest that the mechanisms that influence both species' habitat use and community structure differ among guilds. A single mechanism, operating at a single scale, is inconsistent with these patterns.

With the global population expected to reach almost 10 billion by 2050, there is growing concern for how increasing demands for high-quality, sustainable diets will be met. Whilst food production and environmental conservation are often viewed as competing land uses, a growing body of literature supports the importance of forests in providing food and nutritional security. This study used data from India's National Family Health Survey (NFHS-5) on food consumption and nutritional status in infants and young children aged 6–59 months and tree cover data to examine the statistical associations between tree coverage and indicators of nutritional health in India – a country home to >200 million of the world's undernourished, a rising double burden of malnutrition, and with vast forest and tree cover. In analyses conducted, tree cover was positively associated with higher dietary diversity in infants and young children aged 6–23 months, and with reduced likelihood of stunting and wasting in children aged under 5 yrs. in areas with the highest tree coverages, after controlling for other possible variables. These relationships do not always hold at regional level; further work is needed to explore the mechanisms underlying the relationships examined within given contexts. Overall, these findings indicate the potential for forests and trees to contribute to quality diets in India. In emphasising the potential complementarity between environmental conservation and food provisioning, this work has important implications for food security and environmental policy.

Information on the distribution, area and extent of swidden agriculture landscape is necessary for implementing the program of Reducing Emissions from Deforestation and Forest Degradation (REDD), biodiversity conservation and local livelihood improvement. To our knowledge, explicit spatial maps and accurate area data on swidden agriculture remain surprisingly lacking. However, this traditional farming practice has been transforming into other profit-driven land use, like tree plantations and permanent cash agriculture. Swidden agriculture is characterized by a rotational and dynamic nature of agroforestry, with land cover changing from natural forests, newly-cleared swiddens to different-aged fallows. The Operational Land Imager (OLI) onboard the Landsat-8 satellite has visible, near-infrared and shortwave infrared bands, which are sensitive to the changes in vegetation cover, land surface moisture content and soil exposure, and therefore, four vegetation indices (VIs) were calculated, including the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Moisture Index (NDMI), the Normalized Burn Ratio (NBR) and the Soil Adjusted Vegetation Index (SAVI). In this study, we developed a multi-step threshold approach that uses a combination of thresholds of four VIs and local elevation range (LER) and applied it to detect and map newly-opened swiddens and different-aged fallows using OLI imagery acquired between 2013 and 2015. The resultant Landsat-derived swidden agriculture maps have high accuracy with an overall accuracy of 86.9% and a Kappa coefficient of 0.864. The results of this study indicated that the Landsat-based multi-step threshold algorithms could potentially be applied to monitor the long-term change pattern of swidden agriculture in montane mainland Southeast Asia since the late 1980s and also in other tropical regions, like insular Southeast Asia, South Asia, Latin America and Central Africa, where swidden agriculture is still common.

Changes in vegetation cover are known to influence the climate system by modifying the radiative, momentum, and hydrologic balance of the land surface. To explore the interactions between terrestrial vegetation and the atmosphere for doubled atmospheric CO2 concentrations, the newly developed fully coupled GENESIS–IBIS climate–vegetation model is used. The simulated climatic response to the radiative and physiological effects of elevated CO2 concentrations, as well as to ensuing simulated shifts in global vegetation patterns is investigated. The radiative effects of elevated CO2 concentrations raise temperatures and intensify the hydrologic cycle on the global scale. In response, soil moisture increases in the mid- and high latitudes by 4% and 5%, respectively. Tropical soil moisture, however, decreases by 5% due to a decrease in precipitation minus evapotranspiration. The direct, physiological response of plants to elevated CO2 generally acts to weaken the earth’s hydrologic cycle by lowering transpiration rates across the globe. Lowering transpiration alone would tend to enhance soil moisture. However, reduced recirculation of water in the atmosphere, which lowers precipitation, leads to more arid conditions overall (simulated global soil moisture decreases by 1%), particularly in the Tropics and midlatitudes. Allowing structural changes in the vegetation cover (in response to changes in climate and CO2 concentrations) overrides the direct physiological effects of CO2 on vegetation in many regions. For example, increased simulated forest cover in the Tropics enhances canopy evapotranspiration overall, offsetting the decreased transpiration due to lower leaf conductance. As a result of increased circulation of moisture through the hydrologic cycle, precipitation increases and soil moisture returns to the value simulated with just the radiative effects of elevated CO2. However, in the highly continental midlatitudes, changes in vegetation cover cause soil moisture to decline by an additional 2%. Here, precipitation does not respond sufficiently to increased plant-water uptake, due to a limited source of external moisture into the region. These results illustrate that vegetation feedbacks may operate differently according to regional characteristics of the climate and vegetation cover. In particular, it is found that CO2 fertilization can cause either an increase or a decrease in available soil moisture, depending on the associated changes in vegetation cover and the ability of the regional climate to recirculate water vapor. This is in direct contrast to the view that CO2 fertilization will enhance soil moisture and runoff across the globe: a view that neglects changes in vegetation structure and local climatic feedbacks.

Abstract. Alpine meadow is one of the most widespread grassland types in the permafrost regions of the Qinghai-Tibet Plateau, and the transmission of coupled soil water heat is one of the most crucial processes influencing cyclic variations in the hydrology of frozen soil regions, especially under different vegetation covers. The present study assesses the impact of changes in vegetation cover on the coupling of soil water and heat in a permafrost region. Soil moisture (θv), soil temperature (Ts), soil heat content, and differences in θv−Ts coupling were monitored on a seasonal and daily basis under three different vegetation covers (30, 65, and 93%) on both thawed and frozen soils. Regression analysis of θv vs. Ts plots under different levels of vegetation cover indicates that soil freeze-thaw processes were significantly affected by the changes in vegetation cover. The decrease in vegetation cover of an alpine meadow reduced the difference between air temperature and ground temperature (ΔTa−s), and it also resulted in a decrease in Ts at which soil froze, and an increase in the temperature at which it thawed. This was reflected in a greater response of soil temperature to changes in air temperature (Ta). For ΔTa−s outside the range of −0.1 to 1.0°C, root zone soil-water temperatures showed a significant increase with increasing ΔTa−s; however, the magnitude of this relationship was dampened with increasing vegetation cover. At the time of maximum water content in the thawing season, the soil temperature decreased with increasing vegetation. Changes in vegetation cover also led to variations in θv−Ts coupling. With the increase in vegetation cover, the surface heat flux decreased. Soil heat storage at 20 cm in depth increased with increasing vegetation cover, and the heat flux that was downwardly transmitted decreased. The soil property varied greatly under different vegetation covers, causing the variation of heat conductivity and water-heat hold capacity in topsoil layer in different vegetation cover. The variation of heat budget and transmitting in soil is the main factor that causes changes in soil thawing and freezing processes, and θv−Ts coupling relationship under different vegetation fractions. In addition to providing insulation against soil warming, vegetation in alpine meadows within the permafrost region also would slow down the response of permafrost to climatic warming via the greater water-holding capacity of its root zone. Such vegetation may therefore play an important role in conserving water in alpine meadows and maintaining the stability of engineering works constructed within frozen soil of the Qinghai-Tibet Plateau.

As one of the last agricultural frontiers of the humid tropics, Amazonia is the largest area of the world currently undergoing frontier settlement. Although the earliest intrusions of foreign populations into Amazonia date from pre-Hispanic times, the large-scale entrance of peasant colonists into the vast region is a recent phenomenon. Much of this movement represents the spontaneous migration of peoples, but governments in the region have also become increasingly interested in opening up and integrating Amazonia to national and international economies. These actions are frequently seen as potential solutions to a number of national problems, including the need to increase agricultural production, correct spatial imbalances in the distribution of population, exploit frontier lands for reasons of national security, and defuse potentially serious political problems resulting from the existing agrarian structure, landlessness, and unemployment. The upper basin of the Amazon in Ecuador, bordering on the eastern slopes of the Andes, is one such area of frontier settlement. Recent decades have witnessed the rapid conversion of these Amazonian forests to agricultural uses through a series of schemes bearing such labels as land development and colonization. Most forest intervention in the region has come at the hands of colonist farmers attempting to establish land claims along transport routes originally constructed to aid in petroleum exploration and exploitation. These are farmers who formerly have made a living in long-established farmlands and who, for various reasons (population pressures, pervasive poverty, maldistribution of farmland, lack of inputs for intensive cultivation, lack of nonagrarian livelihood opportunities, and generally inadequate rural development) have been increasingly squeezed out of their homelands. A marginal person by virtue of his low socioeconomic and political status, the farmer often perceives

The forest cover plays an important role in India as well as other countries. The decreasing forest cover in India is one of the major causes of floods in many low-lying areas. Hence, study investigates the novel approach of enhancing flood resilience through strategic augmentation of mixed forest cover in Upper Sabarmati River Basin, Gujarat, India. By leveraging SWAT(Soil &amp; Water Assessment Tool) hydrological model, we explore various land cover change scenarios aimed at increasing mixed forest cover and optimizing plantation types within forested areas. Analyzing land cover data from 1985 to 2017, we introduce three scenarios augmenting mixed forest cover by 3%, 6%, and 9%. Our findings reveal a significant reduction in surface runoff by 4.5%, 7.8%, and 11.6% respectively, highlighting the innovative potential of mixed forest ecosystems in sustainable flood management strategies. This study elucidates the critical role of strategic forest management in mitigating flood risks within river basins, offering valuable insights for environmental policymakers and hydrologists.

Large scale clearing of native forests for agriculture modifies the patterns of rainfall partitioning into evapotranspiration, runoff and infiltration.As deep rooted trees have higher evapotranspiration rates compared with shallow rooted crops for a given amount of rainfall, removal of native trees results in an increased recharge.This can mobilize salts stored in the unsaturated zone and groundwater.The discharge of salts from catchments causes the salinisation of water and land resources in sub-humid to semi-arid regions.In addition to causing significant loss to economy, the salinity issue is a serious threat to the environmental sustainability.Stream salinity being a function of climate, physical characteristics of catchments and land cover, is highly variable in space and time.This variability can be explained on the basis of catchment scale data on climate, catchment attributes and landuse.However, the limitations of data availability require simpler approaches.The aim of this paper is, therefore, to demonstrate the use of readily available catchment-scale data and an annual evapotranspiration model in explaining the variability in stream salinity due to vegetation changes in a sub-humid environment.We use a Budyko-type, an annual evapotranspiration model (Zhang et al. 2004) to understand the effects of vegetation changes on stream salinity.Catchment-scale observed data on climate (mean annual rainfall, actual evapotranspiration, and potential evapotranspiration) and time series of streamflow and salinity from 78 catchments across Victoria, Australia, were used in the analysis.Physical topographic characteristics of the study catchments were derived with the help of a digital elevation model of the area.Spatial information on vegetation, landuse, geology, and soils were obtained from digital maps of these variables.Groundwater salinity was derived from the interpolated surface of salinity data of groundwater bores in the region.The change in the native forest cover was estimated from the native vegetation maps of pre-European settlement (1788) and post-European settlement (1988).Statistical methods, including correlation analysis and ordinary least square regression were used in the analysis.Based on catchment scale observed data and an annual evapotranspiration model (Zhang et al. 2004), it is shown that low flow salinity in our study catchments is highly associated with the evapotranspiration efficiency, fraction of catchment having flatter slopes, and the index of wetness.The analysis for our study region reveals that the catchments having evapotranspiration efficiencies between 0.5-0.6 and catchment parameter 'w' (Zhang et al. 2004) less than 1.46, can have saline low flow.These catchments are characterised with less forest cover, greater fraction of area having flatter slopes and dryland pasture and fall in the medium rainfall zone (500-850mm per year).Correlation analysis shows that low flow salinity is highly associated with evapotranspiration efficiency, index of wetness, catchment fraction having flatter slopes, area under native forests and dryland pasture.An ordinary least squares regression model for low flow salinity identified catchment parameter 'w' and catchment fraction having 2% to 4% slopes and index of wetness as the explanatory variables.We expect that improvement in the model could be achieved by considering other alternatives, such as robust and spatially weighted regression and principal component analysis.

Spatiotemporal variations of Chinese Loess Plateau vegetation cover during 1981-2006 have been investigated using GIMMS and SPOT VGT NDVI data and the cause of vegetation cover changes has been analyzed, considering the climate changes and human activities. Vegetation cover changes on the Loess Plateau have experienced four stages as follows: (1) vegetation cover showed a continued increasing phase during 1981-1989; (2) vegetation cover changes came into a relative steady phase with small fluctuations during 1990-1998; (3) vegetation cover declined rapidly during 1999-2001; and (4) vegetation cover increased rapidly during 2002-2006. The vegetation cover changes of the Loess Plateau show a notable spatial difference. The vegetation cover has obviously increased in the Inner Mongolia and Ningxia plain along the Yellow River and the ecological rehabilitated region of Ordos Plateau, however the vegetation cover evidently decreased in the hilly and gully areas of Loess Plateau, Liupan Mountains region and the northern hillside of Qinling Mountains. The response of NDVI to climate changes varied with different vegetation types. NDVI of sandy land vegetation, grassland and cultivated land show a significant increasing trend, but forest shows a decreasing trend. The results obtained in this study show that the spatiotemporal variations of vegetation cover are the outcome of climate changes and human activities. Temperature is a control factor of the seasonal change of vegetation growth. The increased temperature makes soil drier and unfavors vegetation growth in summer, but it favors vegetation growth in spring and autumn because of a longer growing period. There is a significant correlation between vegetation cover and precipitation and thus, the change in precipitation is an important factor for vegetation variation. The improved agricultural production has resulted in an increase of NDVI in the farmland, and the implementation of large-scale vegetation construction has led to some beneficial effect in ecology.

In this paper, we investigate the features of spatiotemporal change in fractional vegetation cover (FVC) throughout the Yellow River Basin between 2000 and 2022 and identify the driving factors behind the change using the MODIS normalized difference vegetation index (NDVI) as a data source. On that basis, our research involves trend analysis and the center migration model to examine the correlation between vegetation cover changes and various factors, such as climates, topographies, soils, and human activities. In this way, we aim to uncover how such correlation contributed to the reduction in suspended sediment concentration (SSC) in surface runoff. Results suggest that (1) the FVC of the Yellow River Basin has been trending upward over the past 23 years, and vegetation growth has been remarkably improved; (2) the center of medium-high and denser vegetation cover has progressively migrated from the upper reaches of the Yellow River down to its middle-lower segments; (3) soil erosion control measures are critical to improve vegetation cover, given the great impact of the shifting natural elements on vegetation cover changes on a local basis; (4) an improvement in vegetation cover leads to considerable positive change in the runoff and SSC of the Yellow River mainstem. This study has yielded noteworthy contributions in correctly understanding the current vegetation changes and related factors in the Yellow River Basin. Furthermore, it has laid the groundwork for further research in improving the accuracy of basic data and deepening the correlation between factors.

The earth is the home of human survival, and vegetation, as an important natural resource on the land surface, has the functions of sand sealing and soil consolidation, water conservation and so on. Change of vegetation can reflect the change of ecological environment. It is also an important role in the energy cycle and water cycle of the earth's surface and atmosphere. By studying the change of vegetation coverage, we can get the information of ecology and water source. Then, we need to take effective measures to improve our ecological environment. It is also of great significance for us to understand the ecological environment. In this paper, the clear images of 1990, 1998, 2015and 2018in June and July are downloaded from Landsat 8 satellite image data. The vegetation index NDVI of each year is calculated by ArcMap software, and the vegetation coverage is calculated by NDVI. The changes of NDVI and vegetation coverage are analysed. The influencing factors of vegetation coverage and the objective control methods are put forward. Based on the change of vegetation coverage from 1990to 2018, it is concluded that the area of vegetation restoration in the upper reaches of Shiyang River Basin is larger than that of degradation, that in the middle reaches of the basin is larger than that of degradation that in the lower reaches of the basin is larger than that of vegetation restoration, and that in Minqin Basin is larger than that of vegetation restoration Product. Generally speaking, the area of vegetation restoration in Shiyang River Basin is slightly larger than that of vegetation degradation. Based on the statistical analysis of the vegetation coverage in the basin, we should focus on the control of the vegetation in the extremely low vegetation coverage area and the medium vegetation coverage area.

It is generally believed that there is an inverse relationship between population growth and vegetation cover. However, reports about vegetation protection and reforestation around the World have been continuously increasing in recent decades, which seems to indicate that this relationship may not be true. In this paper, we have taken 21 cities in Guangdong Province, China as the study area to test the long-term relationship between population growth and vegetation cover, using an AVHRR NDVI data set and the panel cointegrated regression method. The results show that there is a long-term inverted N-shaped curve relationship between population growth and vegetation cover in the region where there are frequent human activities and the influence of climate change on vegetation cover changes is relatively small. The two turning points of the inverted N-shaped curve for the case of Guangdong Province correspond to 2,200 persons·km−2 and 3,820 persons·km−2, and they can provide a reference range for similar regions of the World. It also states that the population urbanization may have a negative impact on the vegetation cover at the early stage, but have a positive impact at the later stage. In addition, the Panel Error Correction Model (PECM) is used to investigate the causality direction between population growth and vegetation cover. The results show that not only will the consuming destruction effect and planting construction effect induced by the population growth have a great impact on vegetation cover changes, but vegetation cover changes in turn will also affect the population growth in the long term.