Forest Cover Change Assessment in Conflict-affected Areas of Northwest Pakistan: the Case of Swat and Shangla Districts

This study examines the spatial and temporal forest cover changes in Swat and Shangla districts to understand the deforestation pattern in context of the recent security conflict in these districts. We used multi-resolution satellite images to assess the long term deforestation from 2001 to 2009 and also to identify episodic forest cutting areas appeared during the conflict period of Oct. 2007 - Oct. 2008. There are only 58 ha of deforestation identified during the conflict period while 1268 ha of gross annual deforestation were assessed during last eight years. Most of the deforestation patches persist around the administrative boundaries at sub-district levels (tehsils) which can be attributed to ambiguity in unclear jurisdiction between the forest official. The results highlight that the forest cutting appeared in Swat and Shangla during the conflict period is not as significant when compared with the long term deforestation pattern in the area. On the one side the results of the study are supportive to the picture that emerges from international studies which report high rate of deforestation in the country and on the other side it negates any relation between the security situation and the increasing deforestation in the north western Pakistan. The study concludes that deforestation assessments require verification by independent sources of data, such as satellite imagery to improve our understanding of deforestation processes.

Comparison and Analysis of Agricultural and Forest Land Changes in Typical Agricultural Regions of Northern Mid-latitudes

The northeastern China, the United States, and the western Europe are important agricultural regions both on the global and regional scales. The westem Europe has a longer history of agricultural land development than the eastem United States. These two regions have changed from the deforestation and reclamation phase in the past to the current land abandonment and reforestation phase. Compared with the two regions, large-scale land exploitation has only been practiced in the northeastern China during the last century. After a short high-intensity deforestation and reclamation period, agricultural and forest lands are basically in a dynamic steady state. By comparing domestic and international agro-forestry development and considering the ecological environment and socio-economic bene- fits that can be derived from agro-forestry, this paper suggests that large area of reforestation would be inevitable in future though per- sistent and large agricultural demand in coming decades even more. And local reforestation at slope farmland with ecological vulner- ability should be imperative at present to avoid severer damage. At the same time, from the perspective of Land Change Science, the results demonstrate that the research on land use change in the agro-forestry ecotone is typical and critical, particularly those dealing with the analysis of spatial and temporal characteristics and the simulation of climate, hydrology, and other environmental effects.

Changes in vegetation and soil properties during recovery of a subtropical forest in South China

Secondary forests account for a large amount of subtropical forest due to persistent anthropogenic disturbance in China.The interaction between vegetation and soil during recovery process is rather complex and dependent on forest conditions.Understanding how vegetation and soil properties changes and how their relationship develops in secondary forests is key to effective forest restoration and management.Here we explored the patterns of vegetation and soil properties as well as their correlations during forest recovery process in a subtropical forest in south China.Plots of three forest types,i.e.,broadleaf-conifermixedforest,broadleaved forest and old growth stand,were established to represent the recovery stages.The results showed that diversity patterns in the tree,shrub and herb layers were different:in the tree layer the species diversity peaked at the intermediate stage,while in the understory layers it decreased chronologically.Most of the soil factors showed an increasing trend,and different effects of soil factors were found for the three layers as well as for the two spatial scales.Together,our results suggested that vegetation and soil might be interdependent during the recovery course.Further studies are needed on exploring how vegetation interplays with soil at different scales and how nutrient limitations affects the vegetation development in a chronosequence.

Forest cover change and its driving forces in Fagita Lekoma District,Ethiopia

This study investigated forest cover change and the driving forces behind it in Fagita Lekoma District of Ethiopia that resulted in increased forest cover,which might be uncommon outside this case study area.The LULC change analysis was made from 2003 to 2017 based on Landsat images.Socioeconomic analysis was carried out to identify the major driving forces that resulted in LULC change.A questionnaire survey,focused group discussion,key informant interviews and field observation were employed to analyze the link between LULC change and the driving forces.The 15-year period(2003–2017)image analysis revealed that the coverage of forest lands,built-up areas and grassland has increased by 256%,100%and 96%,respectively,at the expense of cultivated lands and wetlands.The increased forest cover is due to the woodlots expansion of Acacia decurrens Willd,which are designed for sustainable livelihoods and a land revitalization strategy in the study area.Rapid population growth,an increasing demand for charcoal and subsequent market opportunities,preferred qualities of A.decurrens or black wattle to halt land degradation as well as to improve land productivity,have been identified as the major driving forces of forest cover change.Chi squared analysis revealed that:a comparative cash income from the sale of A.decurrens;a dependency on natural forests;the distance from the district administrative center;the size of the active labor force,and the area of land owned have significantly affected the cover change.The major forest cover change is due to the expansion of A.decurrens plantations that have socioeconomic and environmental implications to improve rural livelihoods and revitalize the land.Thus,the positive experiences identified in this study should be scaled-up and applied in other similar settings.

Spatial assessment of forest cover and land-use changes in the Hindu-Kush mountain ranges of northern Pakistan

Anthropogenic activities and natural processes are continuously altering the mountainous environment through deforestation, forest degradation and other land-use changes. It is highly important to assess, monitor and forecast forest cover and other land-use changes for the protection and conservation of mountainous environment. The present study deals with the assessment of forest cover and other land-use changes in the mountain ranges of Dir Kohistan in northern Pakistan, using high resolution multi-temporal SPOT-5 satellite images. The SPOT-5 satellite images of years 2004, 2007, 2010 and 2013 were acquired and classified into land-cover units. In addition, forest cover and land-use change detection map was developed using the classified maps of 2004 and 2013. The classified maps were verified through random field samples and Google Earth imagery(Quick birds and SPOT-5). The results showed that during the period 2004 to 2013 the area of forest land decreased by 6.4%, however, area of range land and agriculture land have increased by 22.1% and 2.9%, respectively. Similarly, barren land increased by 1.1%, whereas, area of snow cover/glacier is significantly decreased by 21.3%. The findings from the study will be useful for forestry and landscape planning and can be utilized by the local, provincial and national forest departments; and REDD+ policy makers in Pakistan.

The rapid climate change-caused dichotomy on subtropical evergreen broad-leaved forest in Yunnan： Reduction in habitat diversity and increase in species diversity

Yunnan's biodiversity is under considerable pressure and subtropical evergreen broad-leaved forests in this area have become increasingly fragmented through agriculture,logging,planting of economic plants,mining activities and changing environment.The aims of the study are to investigate climate changeinduced changes of subtropical evergreen broad-leaved forests in Yunnan and identify areas of current species richness centers for conservation preparation.Stacked species distribution models were created to generate ensemble forecasting of species distributions,alpha diversity and beta diversity for Yunnan's subtropical evergreen broad-leaved forests in both current and future climate scenarios.Under stacked species distribution models in rapid climate changes scenarios,changes of water-energy dynamics may possibly reduce beta diversity and increase alpha diversity.This point provides insight for future conservation of evergreen broad-leaved forest in Yunnan,highlighting the need to fully consider the problem of vegetation homogenization caused by transformation of water-energy dynamics.

Forest cover change and its effects on the livelihood of the dependent local people:the case of Sesheke district of Zambia

Objective-To investigate forest cover change in Masese Local Forest Reserve and its effects on the livelihoods of the dependent communities;to establish the occurrence of forest cover change in Masese Local Forest Reserve;to determine the extent of forest cover change in Masese from 1990to 2005;to determine the tree species that have been affected by forest cover change in Masese; and to assess the effects of forest cover change on the livelihoods of the dependent communities. Methods-Interviews and questionnaire were conducted with a proportion of 36households from Maondo and 84households from Mulimambango settlements.Scenes of landsat images of 1990,2000, 2005and Earth Google image for Masese were used for map analysis.Also remote sensing was used to analyze landsat images and Google image to detect forest and non-forest classes.Results and Conclusion-Forest cover change has adverse implication on the provision of wood forest products and nonwood forest products to the dependent local communities.The declining status of dominant Baikiaea Forest that has exploitable species for building materials and fuel wood has affected the livelihoods of the dependent local communities.There is also increased cost and shortage of fire wood and building materials due to deforestation in Masese Forest Reserve.

Forest cover dynamics in Palas Valley Kohistan, Hindu Kush-Himalayan Mountains, Pakistan

Forest cover change in the mountainous region is driven by a variety of anthropogenic and natural factors.The Hindu Kush-Himalayan Mountains has experienced a considerable vegetation cover change due to intensive human activities,such as population growth,proximate causes,accessibility,unstable political situations,government policy failure and poverty.The present study seeks to find out the impact of population growth and road network expansion on forest cover of Palas valley based on remotely sensed data and employing geospatial techniques.Changes in forest cover were determined by classifying time-series satellite images of Landsat and Sentinel 2 A.The images of October 1980,2000,2010 and 2017 were classified into six land cover classes and then the impact of population growth and accessibility on forest cover was analyzed.Furthermore,forest cover and land-use change detection map was prepared using classified images of 1980 and 2017.The data were collected mainly from field visits(ground verification),census reports,Communication and Works Department,Kohistan.Satellite imageries were obtained from the United States Geological Survey’s websites and classified in ERDAS imagine 2014 and ESRI ArcGIS 10.2.1 using supervised classification-maximum likelihood algorithm.Result of this study revealed that a substantial reduction in forest cover has taken place mainly in the proximity of human settlements.On the average,during the study period,annually more than 460 hectares of forest area has been converted into other uses.

Using modified Soil Conservation Service curve number method to simulate the role of forest in flood control in the upper reach of the Tingjiang River in China

To improve flood control efficiency and increase urban resilience to flooding,the impacts of forest type change on flood control in the upper reach of the Tingjiang River(URTR) were evaluated by a modified model based on the Soil Conservation Service curve number(SCS-CN) method. Parameters of the model were selected and determined according to the comprehensive analysis of model evaluation indexes. The first simulation of forest reconstruction scenario,namely a coniferous forest covering 59.35km^2 is replaced by a broad-leaved forest showed no significant impact on the flood reduction in the URTR. The second simulation was added with 61.75km^2 bamboo forest replaced by broad-leaved forest,the reduction of flood peak discharge and flood volume could be improved significantly. Specifically,flood peak discharge of 10-year return period event was reduced to 7-year event,and the reduction rate of small flood was 21%-28%. Moreover,the flood volume was reduced by 9%-14% and 18%-35% for moderate floods and small floods,respectively. The resultssuggest that the bamboo forest reconstruction is an effective control solution for small to moderate flood in the URTR,the effect of forest conversion on flood volume is increasingly reduced as the rainfall amount increases to more extreme magnitude. Using a hydrological model with scenarios analysis is an effective simulation approach in investigating the relationship between forest type change and flood control. This method would provide reliable support for flood control and disaster mitigation in mountainous cities.

Effects of Forest Type and Urbanization on Carbon Storage of Urban Forests in Changchun, Northeast China

Rapid urbanization has led to dramatic changes in urban forest structures and functions, and consequently affects carbon(C) storage in cities. In this study, field surveys were combined with high resolution images to investigate the variability of C storage of urban forests in Changchun, Northeast China. The main objectives of this study were to quantify the C storage of urban forests in Changchun City, Northeast China and understand the effects of forest type and urbanization on C storage of urban forests. The results showed that the mean C density and the total C storage of urban forests in Changchun were 4.41 kg/m2 and 4.74 × 108 kg, respectively. There were significant differences in C density among urban forest types. Landscape and relaxation forest(LF) had the highest C density with 5.41 kg/m2, while production and management forest(PF) had the lowest C density with 1.46 kg/m2. These differences demonstrate that urban forest type is an important factor needed to be considered when the C storage is accurately estimated. Further findings revealed significant differences in different gradients of urbanization, and the mean C density decreased from the first ring(6.99 kg/m2) to the fourth ring(2.87 kg/m2). The total C storage increased from the first ring to the third ring. These results indicate that C storage by urban forests will be significantly changed during the process of urbanization. The results can provide insights for decision-makers and urban planners to better understand the effects of forest type and urbanization on C storage of urban forests in Changchun, and make better management plans for urban forests.

Disturbance and forest recovery in the Monarch Butterfly Biosphere Reserve,Mexico

Analysis of the change in forest cover is important to determine stand dynamics and the processes involved in disturbance and recovery.Forests of the core zone of the Monarch Butterfly Biosphere Reserve were studied using photo interpretation techniques,considering biennial changes between 1999 and 2013 and changes over the whole period of study 1999–2013.Error matrices were elaborated to determine the processes of change involved in both recovery and disturbance.The biennial changes for the whole period amounted to 2274 ha;343 ha accounted as degraded in more than one biennial period.The total changes in forest cover between 1999 and 2013 involved 4902 ha,out of which,2912 ha were affected by disturbance,and 1990 ha were recovered.For density and 2013 vegetation cover maps,the overall accuracy was 95.6%and 90.2%,respectively.By combining both maps,gradual processes were revealed that were not evident in separate analyses.This methodology is useful for the management and conservation of natural protected areas.

Evolution of forest cover in Portugal: A review of the 12th–20th centuries

Portugal＇s forests in the 12th century were dominated by the Fagaceae represented by Quercus and Castanea, and several pine species From the 12th century onwards, forests underwent changes in their management starting with protection and ultimately leading to intense exploitation. The massive naval construction during the maritime expansion （mainly in the 15th-16th centuries） involved felling of approximately 5 million trees mainly Quercus suber, Pinus pinea and other Quercus species. Cumulative fuel-wood consumption of 959 Mm3 during 1300-1854 was attributed to demographic expansion while the deforestation rate during 1636-1854 accounted for a minimum of 72.6% and a maximum of 96% of total forest cover. The volume of timber used in railway sleepers from 1856 onwards might have reached 0.5 Mm3. The last quarter of the 20th century increased the forest cover of Portugal through the World Bank program of Eucalyptus globulus reforestation.

Towards long-multitemporal change detection using SVI differencing by integrated DWT
ISOCLUS: a model for forest temporal dynamics mapping

Characterisation and mapping of land cover/land use within forest areas over long-multitemporal intervals is a complex task.This complexity is mainly due to the location and extent of such areas and,as a consequence,to the lack of full continuous cloud-free coverage of those large regions by one single remote sensing instrument.In order to provide improved long-multitemporal forest change detection using Landsat MSS and ETMin part of Mt.Kenya rainforest,and to develop a model for forest change monitoring,wavelet transforms analysis was tested against the ISOCLUS algorithm for the derivation of changes in natural forest cover,as determined using four simple ratio-based Vegetation Indices:Simple Ratio(SR),Normalised Difference Vegetation Index(NDVI),Renormalised Difference Vegetation Index(RDVI)and modified simple ratio(MSR).Based on statistical and empirical accuracy assessments,RDVI presented the optimal index for the case study.The overall accuracy statistic of the wavelet derived change/no-change was used to rank the performances of the indices as:RDVI(91.68%),MSR(82.55%),NDVI(79.73%)and SR(65.34%).The integrated discrete wavelet transform
ISOCLUS(DWT
ISOCLUS)result was 42.65%higher than the independent ISOCLUS approach in mapping the change/no-change information.The methodology suggested in this study presents a cost-effective and practical method to detect land-cover changes in support of decision-making for updating forest databases,and for long-term monitoring of vegetation changes from multisensor imagery.The current research contributes to Digital Earth with regards to geo-data acquisition,data mining and representation of one forest systems.

Assessment of the three factors affecting Myanmar’s forest cover change using Landsat and MODIS vegetation continuous fields data

Long-term observation of the earth is essential for studying the factors affecting global environmental changes.Digital earth technology can facilitate the monitoring of global environmental change with its ability to process vast amounts of information.In this study,we map the forest cover change of Myanmar from 2000 to 2005 using a training data automation procedure and support vector machines algorithm.Our results show that Myanmar’s forests have declined 0.68%annually over this six-year period.We validated our derived change results and found the overall accuracy to be greater than 88%.We also assessed forest loss from protected areas,areas close to roads,and areas subject to fire,which were most likely to lose forested area.The results revealed the main reasons for forest losses in some hotspots to be increased agricultural conversion,fire,and the construction of highways.This information is useful for identifying the driving forces behind forest changes and to support environmental policy development in Myanmar.

A remotely sensed tracking of forest cover and associatedtemperature change in Margalla hills

Worldwide, forest degradation is a serious environmental issue, and inPakistan, forest wealth is depleting at the highest rate in South Asia. Toensure sustainable development goals of environmental stewardship,social development and economic growth, a sound monitoring andregulatory mechanism is essential for tracking forest cover changes. Thisstudy aims to quantify the decline of forest reserves and associatedtemperature variations in a relatively unexplored biodiversity hotspot ofIslamabad, Margalla Hills National Park (MHNP). Imagery acquired byLandsat TM (Thematic Mapper) for the year 1992, 2000 and 2011 areused to assess the spatial and temporal changes occurred over the lasttwo decades (from 1992 to 2011). A robust hybrid-classification routineis implemented to monitor the changes in forest cover and ANOVAalong with Tukey’s HSD (Honestly Significant Difference) test is used totest the significance of temperature variation associated with a shift inland cover classes. The results showed a significant growth insettlements, agricultural area and barren soil whereas water body, lowervegetation, scrub and pine forest are diminishing. In both decades, thetemperature alteration associated with a change in land cover classesare statistically significant (confirmed by ANOVA and Tukey’s HSD tests)for most of the land use/land cover classes. Based on these findings, thisstudy concludes that forests are dwindling at MHNP and the degradingcondition of the forest is below par and necessitates the promotion ofconservation practices to minimize ecological disturbances.

Fuelwood assessment at micro-watershed level in Northeast Himalaya:a case study in Manipur,India

Fuelwood is one of the major sources of energy in the domestic sector across the rural areas,especially in the developing regions across the world.The Northeastern Himalayan state of Manipur is dominated by the tribal population that largely depends on fuelwood from the nearby forest area.The entire dependence on forests for energy resources is affecting the sustainability of the forest ecosystem in the region,thus indicating the livelihood conditions.Since land-use land-cover change is the key driver to the change in resource availability of a region,the present study has tried to analyze the landcover changes over a period 28 years.The second major component affecting resource availability is the increasing population pressure that leads to changes in the land dynamics,which directly affect the resource production.Based on the existing consumption pattern,the total consumption of fuelwood in the watershed ranges from a rrrinimum of 289.992 tons/year to a maximum of 3545.719 tons/year with an average of 1561.956 tons/year in the year 2009 and simulated fuelwood consumption for the year 2021 is around 1469.260 tons/year.Nine different probable scenarios of resource are proposed to calculate the stress value that can be used by the policy-makers and planners for suitable policy implementation at the micro level with a complex social system.

Development of time series stacks of Landsat images for reconstructing forest disturbance history

Forest dynamics is highly relevant to a broad range of earth science studies,many of which have geographic coverage ranging from regional to global scales.While the temporally dense Landsat acquisitions available in many regions provide a unique opportunity for understanding forest disturbance history dating back to 1972,large quantities of Landsat images will need to be analysed for studies at regional to global scales.This will not only require effective change detection algorithms,but also highly automated,high level preprocessing capabilities to produce images with subpixel geolocation accuracies and best achievable radiometric consistency,a status called imagery-ready-to-use(IRU).This paper describes a streamlined approach for producing IRU quality Landsat time series stacks(LTSS).This approach consists of an image selection protocol,high level preprocessing algorithms and IRU quality verification procedures.The high level preprocessing algorithms include updated radiometric calibration and atmospheric correction for calculating surface reflectance and precision registration and orthorectification routines for improving geolocation accuracy.These automated routines have been implemented in the Landsat Ecosystem Disturbance Adaptive System(LEDAPS)designed for processing large quantities of Landsat images.Some characteristics of the LTSS developed using this approach are discussed.

Global characterization and monitoring of forest cover using Landsat data: opportunities and challenges

The compilation of global Landsat data-sets and the ever-lowering costs of computing now make it feasible to monitor the Earth’s land cover at Landsat resolutions of 30 m.In this article,we describe the methods to create global products of forest cover and cover change at Landsat resolutions.Nevertheless,there are many challenges in ensuring the creation of high-quality products.And we propose various ways in which the challenges can be overcome.Among the challenges are the need for atmospheric correction,incorrect calibration coefficients in some of the data-sets,the different phenologies between compila-tions,the need for terrain correction,the lack of consistent reference data for training and accuracy assessment,and the need for highly automated character-ization and change detection.We propose and evaluate the creation and use of surface reflectance products,improved selection of scenes to reduce phenological differences,terrain illumination correction,automated training selection,and the use of information extraction procedures robust to errors in training data along with several other issues.At several stages we use Moderate Resolution Spectro-radiometer data and products to assist our analysis.A global working prototype product of forest cover and forest cover change is included.

Selection and quality assessment of Landsat data for the North American forest dynamics forest history maps of the US

Using the NASA Earth Exchange platform,the North American Forest Dynamics(NAFD)project mapped forest history wall-to-wall,annually for the contiguous US(1986–2010)using the Vegetation Change Tracker algorithm.As with any effort to identify real changes in remotely sensed time-series,data gaps,shifts in seasonality,misregistration,inconsistent radiometry and cloud contamination can be sources of error.We discuss the NAFD image selection and processing stream(NISPS)that was designed to minimize these sources of error.The NISPS image quality assessments highlighted issues with the Landsat archive and metadata including inadequate georegistration,unreliability of the pre-2009 L5 cloud cover assessments algorithm,missing growing-season imagery and paucity of clear views.Assessment maps of Landsat 5–7 image quantities and qualities are presented that offer novel perspectives on the growing-season archive considered for this study.Over 150,000+Landsat images were considered for the NAFD project.Optimally,one high quality cloud-free image in each year or a total of 12,152 images would be used.However,to accommodate data gaps and cloud/shadow contamination 23,338 images were needed.In 220 specific path-row image years no acceptable images were found resulting in data gaps in the annual national map products.