Vegetation Index Variables Research Articles

Detecting spatio-temporal and typological changes in land use from Landsat image time series

With the development of earth observation technology, the spatial and temporal resolution of remote sensing images have improved dramatically, providing abundant data for detecting land use change in detail. However, extracting spatio-temporal and typological changes in land use from remote sensing image time series is still challenging. Landsat image time series and land survey data are combined to develop a method to detect in detail the time and types of land use change. From the Landsat images, the time series of normalized difference vegetation index variation slope (TSNVS) on each pixel was constructed. The average TSNVS of sample pixels was used as the reference series. Based on TSNVS, the change in land use at six time points (S1 to S6) was detected by measuring the similarity of the time series on undetermined pixels and reference series. Land survey data were used to identify detailed types of land use change. The 16 different types of land use change were identified. The results indicate that the proposed method is effective at detecting spatio-temporal and typological changes in land use from Landsat image time series. After verification, the overall accuracy was 92%, and the kappa coefficient was 0.9.

Species diversity and population distribution of arboreal mammals in Kemuning Forest, Temanggung, Central Java, Indonesia

Krisanti AA, Widiyani T, Imron MA. 2017. Species diversity and population distribution of arboreal mammals in Kemuning Forest, Temanggung, Central Java, Indonesia. Biodiversitas 18: 1190-1195. Arboreal mammals which spent their life on the trees have significant roles for ecosystem balance and sustainability of forest ecosystem. This research aimed to reveal the diversity, population distribution, and the habitat used by arboreal mammals in Kemuning Forest of Bejen, Temanggung, Central Java, Indonesia. We conducted observation on the presence of arboreal mammals during four weeks started from April to July 2016. The observation was done within various times a day depends on the weather. 30 strips transect (ST) with 200m in length were established following the existing walking path for species identification. Point-quarter samplings (PQS) were used at every 50m of the track length for measuring diversity, density, and determining the dominant vegetation. There were 137 individuals of arboreal mammals detected and classified in 6 species, i.e., Callosciurus notatus, Ratufa bicolor, Galeopterus variegatus, Macaca fascicularis, Trachypithecus auratus, and Nycteris javanica. The largest population was M. fascicularis while the smallest was G. variegatus. There were 28 species of identified trees. Animals were observed in 22 tracks while the other six tracks were out of detected animals, so the relative frequency of animal was 80%. Diversity indices (H’) of the animal were 1.342, whereas the vegetation diversity indices were 2.795. Dominant vegetation species were Ficus macrophylla (36%). The arboreal mammals were distributed in a clumped pattern. We concluded that Kemuning Forest had the potential to be the suitable habitat for arboreal mammals with better managements.

KOMPOSISI POHON DI BUKIT ACE KELURAHAN GUNUNG SARIK KECAMATAN KURANJI PADANG

The existence of trees in a region could be threatened because of their good forest damage due to natural factors such as fires and landslides, as well as human activities mainly due to illegal logging. This study aims to determine the composition of a tree in Bukit Ace in the sub Kuranji Padang. In this study using a survey method using a combination of methods to make trransek track and map examples. Transects were observed along the 20 meter by 10 mapped sample with a size of 10x10 meter Analysis of vegetation cover density, frequency, dominance, importance and diversity index. Based on research conducted at the Mount Ace Village of Mount Sarik District of Kuranji Padang, tree composition consists of 13 species and 172 individuals where species of trees by people who at least is Anacardium ocidentale ie 3 people whereas species with people most is Xerospermum intermedium (31 people) , Important values ranging between 6.107% - 60.327%, of tree species that have significant value the highest is Xerospermum intermedium is 60.327% and tree species with important value lows are Evodia malayana namely 6.107%, while based on diversity index of forest in Bukit Ace classified as being abundant with value ID 2,351.

How can satellite imagery be used for mineral exploration in thick vegetation areas?

AbstractThe Hokuroku district, northern Japan, is globally recognized for rich ore deposits (kuroko and vein types), which have been thoroughly explored under thick vegetation cover. This situation is ideal to evaluate the effects of ore deposits on vegetation anomalies through geobotanical remote sensing. Here we present novel methods to detect vegetation anomalies caused by ore deposits and verify their usefulness by comparing the anomalies with a deposit potential map produced from multiple geological data. We use the reflectance spectra of Landsat ETM+ images acquired in summer and autumn to calculate a vegetation index for plant physiological activity. A key variable to detect the anomalies is a variation of vegetation index with time at each pixel. Difference in variation is enlarged by a sequence of image enhancement methods for the detection. We find that the vegetation anomalies, defined by the large ratios, correspond well to the high potential zones of ore deposits and known major deposits. Consequently, our methods can extend the applicability of remote sensing‐based mineral exploration to the areas covered by thick vegetation, in addition to traditional arid and semiarid areas.

Structure of plant community in tropical deciduous forests of Kanyakumari Wildlife Sanctuary, India

Abstract. Kothandaraman S, Sundarapandian S.2017. Structure of plant community in tropical deciduous forests of Kanyakumari Wildlife Sanctuary, India. Biodiversitas 18: 391-400. Plantcommunity structure of two tropical deciduous forest sites (I and II which are in different locations with different terrain characteristics viz., elevation and slope pattern) in Kanyakumari Wildlife Sanctuary, Western Ghats were assessed using standard phytosociological methods. Ten plots of 20 m x 20 m each were laid for woody species enumeration and 40 quadrats of 1 m x 1 m (4 in each plot) for understorey vegetation (herbs and plant species that are < 1 m in height) in each site. Overall, 76 plant species were recorded from 41 families, of which 23 contribute to understory. Site I (62) was twice as speciose as site II (31). Greater diversity index of adult woody vegetation was observed in site I (2.30) than site II (2.01). The woody individuals (diameter at breast height, DBH ≥ 10 cm) were more abundant in site I (518 individuals ha-1) than site II (448 individuals ha-1). The basal area of adult trees in sites I and II are 34.7 m2 ha-1 and 30.8 m2 ha-1 respectively. Euphorbiaceae was the most speciose family in both the sites. Twenty-five families in site I and seventeen families in site II were represented by singletons. Diameter class-wise distribution of adult trees showed a typical ‘reverse J-shaped’ curve indicating good regeneration status. Concerning understory, site I (19 species) has a greater diversity than site II (six species). The observed differences in the vegetation patterns between the two deciduous forest sites are possibly due to variations in elevation, terrain features and edaphic characteristics.
 Keywords: Phytodiversity, species richness, tropical forests, Western Ghats

Examining view angle effects on leaf N estimation in wheat using field reflectance spectroscopy

Real-time, nondestructive monitoring of crop nitrogen (N) status is a critical factor for precision N management during wheat production. Over a 3-year period, we analyzed different wheat cultivars grown under different experimental conditions in China and Canada and studied the effects of viewing angle on the relationships between various vegetation indices (VIs) and leaf nitrogen concentration (LNC) using hyperspectral data from 11 field experiments. The objective was to improve the prediction accuracy by minimizing the effects of viewing angle on LNC estimation to construct a novel vegetation index (VI) for use under different experimental conditions. We examined the stability of previously reported optimum VIs obtained from 13 traditional indices for estimating LNC at 13 viewing zenith angles (VZAs) in the solar principal plane (SPP). Backscattering direction showed better index performance than forward scattering direction. Red-edge VIs including modified normalized difference vegetation index (mND705), ratio index within the red edge region (RI-1dB) and normalized difference red edge index (NDRE) were highly correlated with LNC, as confirmed by high R2 determination coefficients. However, these common VIs tended to saturation, as the relationships strongly depended on experimental conditions. To overcome the influence of VZA on VIs, the chlorophyll- and LNC-sensitive NDRE index was divided by the floating-position water band index (FWBI) to generate the integrated narrow-band vegetation index. The highest correlation between the novel NDRE/FWBI parameter and LNC (R2=0.852) occurred at −10°, while the lowest correlation (R2=0.745) occurred at 60°. NDRE/FWBI was more highly correlated with LNC than existing commonly used VIs at an identical viewing zenith angle. Upon further analysis of angle combinations, our novel VI exhibited the best performance, with the best prediction accuracy at 0° to −20° (R2=0.838, RMSE=0.360) and relatively good accuracy at 0° to −30° (R2=0.835, RMSE=0.366). As it is possible to monitor plant N status over a wide range of angles using portable spectrometers, viewing angles of as much as 0° to −30° are common. Consequently, we developed a united model across angles of 0° to −30° to reduce the effects of viewing angle on LNC prediction in wheat. The proposed combined NDRE/FWBI parameter, designated the wide-angle-adaptability nitrogen index (WANI), is superior for estimating LNC in wheat on a regional scale in China and Canada.

ANALISIS KOMPOSISI DAN STRUKTUR VEGETASI UNTUK MENENTUKAN INDEKS KEANEKARAGAMAN DI KAWASAN HUTAN KOTA PEKANBARU

ABSTRAK : Penelitian ini bertujuan menganalisis komposisi dan struktur vegetasi untuk menentukan indeks keanekaragaman di kawasan hutan kota Pekanbaru. Lokasi penelitian terletak di kawasan hutan kota jalan Thamrin Pekanbaru, Provinsi Riau. Kawasan hutan kota Pekanbaru ini mempunyai luas areal sebesar 6,1 Ha. Penelitian ini merupakan penelitian survei dengan metode kuadran. Penentuan plot sampel menggunakan teknik simple random sampling. Teknik analisis data menggunakan rumus Shanon-Wienner, dengan mencari nilai kerapatan, frekuensi, dominansi, dan indeks nilai penting. Hasil penelitian menunjukkan kawasan hutan kota Pekanbaru memiliki tingkat indeks keanekaragaman vegetasi pohon adalah 2,83 yang tergolong dalam kriteria sedang. Indeks keanekaragaman vegetasi tiang adalah 2,24 yang tergolong dalam kriteria sedang. Indeks keanekaragaman vegetasi pancang adalah 1,91 yang tergolong dalam kriteria sedang. Indeks keanekaragaman vegetasi semai adalah 2,02 yang tergolong dalam kriteria sedang.

Effects of grazing intensity on soil organic carbon of rangelands in Xilin Gol League, Inner Mongolia, China

Changes in soil organic carbon (SOC) in rangelands has been extensively investigated. Grazing in outlying rangeland areas has caused severe impacts on ecosystem functions. To reveal the effects of grazing on SOC, we evaluated the grassland in Xilin Gol League, Inner Mongolia, China. Grazing intensity was determined by using two image sets of vegetation index with normalized differences in grazing periods (July 12th and 28th). The range of variation in vegetation index was then used to measure the grazing intensity. The SOC storage and density were obtained by conducting experiments on field soil samples. Results showed that 1) the grazing intensity in Xilin Gol League declined gradually from west to east; by contrast, the spatial distribution of SOC density increased gradually. 2) As grazing intensity increased, the carbon storage of rangeland decreased evidently. Minimum carbon storage was observed in grasslands classified under extreme overgrazing; by comparison, maximum values were found in areas classified under light overgrazing to moderate grazing. 3) The estimated soil carbon storage was 8.48 × 1011 kg, and the average carbon density was 4.08 kg/m2. Our research demonstrated that grazing intensity likely affects soil carbon. Moderate grazing is an optimum strategy to maintain carbon storage and ensure sustainable grassland utilization.

A Case Study on the Landuse Pattern of Kanyakumari DistrictUsing Gis

The fundamental pattern of the land use is the exactness in vegetation strategies. This study focus on the landcover patterns of Kanyakumari district using geographical information system.The evolution of landuse patterns are made using landsat imagery. The variations of vegetation index are determined using ArcGIS softwareThe key advancement in implementing this study is to give brief information about the aerial land classification and human activities over the region of interest. Geo-Satellite information about vegetation land- cover helps us to be more proficient in fragmenting areas. The end goal is to decide the type of field patterns and an appropriate area for profitable utilization of land cover features which leads to efficient vegetation.

TREES VEGETATION DIVERSITY IN PT ARUN NGL HOUSING, LHOKSEUMAWE, ACEH PROVINCE

The research about trees vegetation diversity in PT Arun NGL area had been done in December 2012. The objective of the research was to calculate the trees vegetation diversity index. The data had been collected in nine belt transects by length 400 m and 400 m2 (10 m x 40 m) plots for each belt transect. The collecting data was including name of species, family, density, frequency and dominancy. The data was analyzed to get important value and diversity index. The result showed that there were 39 tree species belongs to 23 families found in the research area. There were three dominant species namely; Pterocarpus indicus, Pithecelobium dulce, dan Leucaena leucocephala which had higher important value than others species that lead influencing the ecosystem. The trees diversity index in this area was about 3,3 which interpreted this area has high diversity index. Moreover, the plants were planted in PT Arun NGL Housing Area have another function as reducing pollutant material in the air.

Identifying forest ecosystem regions for agricultural use and conservation

Balancing agricultural needs with the need to protect biodiverse environments presents a challenge to forestry management. An imbalance in resource production and ecosystem regulation often leads to degradation or deforestation such as when excessive cultivation damages forest biodiversity. Lack of information on geospatial biodiversity may hamper forest ecosystems. In particular, this may be an issue in areas where there is a strong need to reassign land to food production. It is essential to identify and protect those parts of the forest that are key to its preservation. This paper presents a strategy for choosing suitable areas for agricultural management based on a geospatial variation of Shannon's vegetation diversity index (SHDI). This index offers a method for selecting areas with low levels of biodiversity and carbon stock accumulation ability, thereby reducing the negative environmental impact of converting forest land to agricultural use. The natural forest ecosystem of the controversial 1997 Ex-Mega Rice Project (EMRP) in Indonesia is used as an example. Results showed that the geospatial pattern of biodiversity can be accurately derived using kriging analysis and then effectively applied to the delineation of agricultural production areas using an ecological threshold of SHDI. A prediction model that integrates a number of species and families and average annual rainfall was developed by principal component regression (PCR) to obtain a geospatial distribution map of biodiversity. Species richness was found to be an appropriate indicator of SHDI and able to assist in the identification of areas for agricultural use and natural forest management.

Plant diversity and relationships with environmental factors after rangeland exclosure in arid Tunisia

On a broad scale, the extent of clearing and plowing of the crops in rangelands has brought a significant degradation in pasture species along with an invasion of weed species. This work evaluates the vegetation composition of an agriculture field after 15 years of exclosure and protection against clearing and plowing activities. Vegetation cover, density, richness, species dispersion, and diversity index were estimated through 12 permanent transects of 20 m in length and 23 quadrats of 1 m2 over a 3-year period. Species diversity and its relationship with environmental factors (soil, canopy, elevation, and road effect) were analyzed by canonical correlation analysis. About 72 species were recorded across the study area. Plant species encountered were divided into three communities of steppic (45.8%), weed (44.4%), and steppic-weed (8.4%), with 1 cultivated species (1.4%). Raunkiaer classification showed a dominance of therophytes (73.6%) over the other groups. This work showed that exclosure of degraded arid lands can regenerate 16.6% of perennial plant cover that allowed to classify the experimental field as a low degraded zone.

The Effect of Soil Moisture on the Reflectance Spectra Correlations in Beech and Sessile Oak Foliage/ Talajnedvesség hatása bükk és kocsánytalan tölgy lombozat reflexiós spektrumainak korrelációira.

Abstract Reflectance intensities of foliage are mostly due to biomaterials synthesised by plants. Adaptation to the continuously changing environment requires the regulated alteration of metabolic processes, which also influences the UV-VIS (Ultraviolet-Visible) and IR (Infra Red) spectra of leaves. For the calculation of various Vegetation Indices (VIs), e.g. NDVI (Normalized Difference Vegetation Index), the common practice is to use the reflectance spectrum of the whole foliage and when individual leaves of the same plant are sampled, an average VI is derived. On the contrary, our method exploits the small differences between individual leaves of the same plant, making use of the similar distributions of measured reflectance values. Using particular wavelength pairs, linear regressions of reflectance intensities have been investigated. The parameters of these regressions (slope and intercept) have been compared to the temporal variations of the environmental factors, such as temperature, vapour pressure deficit and soil moisture. By assessing the sensitivity of the regression coefficient (slope) to the changing environment, wavelength pairs can be selected whose sensitivity change reflects the effect of soil moisture deficit on the plant. Based on the state-dependent correlations of the reflectance spectra of plant foliage, a new concept is presented that is capable of indicating the level of environmental stress, e.g. drought stress.

Evaluating Different Methods for Grass Nutrient Estimation from Canopy Hyperspectral Reflectance

The characterization of plant nutrients is important to understand the process of plant growth in natural ecosystems. This study attempted to evaluate the performances of univariate linear regression with various vegetation indices (VIs) and multivariate regression methods in estimating grass nutrients (i.e., nitrogen (N) and phosphorus (P)) with canopy hyperspectral reflectance. Synthetically considering predictive accuracy, simplicity, robustness and interpretation, the successive projections algorithm coupled with multiple linear regression (SPA-MLR) method was considered optimal for grass nutrient estimation at the canopy level, when compared with the performances of 12 statistical modeling methods, i.e., univariate linear regression with nine published VIs and three classical multivariate regression methods (stepwise multiple linear regression (SMLR), partial least squares regression (PLSR) and support vector regression (SVR)). The simple ratio index ( , is derivative reflectance) model had comparable performance to SPA-MLR model for P estimation. SPA-MLR provided comparable prediction accuracies with only three first derivative spectral bands for N (715, 731 and 2283 nm) and P (714, 729 and 1319 nm) estimations, compared with PLSR and SVR models, which used the full spectrum. Moreover, SPA-MLR provided robust prediction with the lowest bias values for N (−0.007%) and P (0.001%) estimations, and the fitting line between predicted and measured values was closer to the 1:1 line than the other models. Finally, most of the bands selected by SPA-MLR indirectly relate to foliar chlorophyll content, which suggests good physical interpretation.

Spectra and vegetation index variations in moss soil crust in different seasons, and in wet and dry conditions

Similar to vascular plants, non-vascular plant mosses have different periods of seasonal growth. There has been little research on the spectral variations of moss soil crust (MSC) over different growth periods. Few studies have paid attention to the difference in spectral characteristics between wet MSC that is photosynthesizing and dry MSC in suspended metabolism. The dissimilarity of MSC spectra in wet and dry conditions during different seasons needs further investigation. In this study, the spectral reflectance of wet MSC, dry MSC and the dominant vascular plant (Artemisia) were characterized in situ during the summer (July) and autumn (September). The variations in the normalized difference vegetation index (NDVI), biological soil crust index (BSCI) and CI (crust index) in different seasons and under different soil moisture conditions were also analyzed. It was found that (1) the spectral characteristics of both wet and dry MSCs varied seasonally; (2) the spectral features of wet MSC appear similar to those of the vascular plant, Artemisia, whether in summer or autumn; (3) both in summer and in autumn, much higher NDVI values were acquired for wet than for dry MSC (0.6∼0.7 vs. 0.3∼0.4 units), which may lead to misinterpretation of vegetation dynamics in the presence of MSC and with the variations in rainfall occurring in arid and semi-arid zones; and (4) the BSCI and CI values of wet MSC were close to that of Artemisia in both summer and autumn, indicating that BSCI and CI could barely differentiate between the wet MSC and Artemisia.

An Alternative Rangeland Management Strategy in an Agro-Pastoral Area in Western China

Governance plays a key role in rangeland management. In China, all rangeland, including pastoral land and agro-pastoral land, is owned by the State. Since 1980, use rights have been granted to households by the Chinese government extending the household contract responsibility system (HCRS). But in the agro-pastoral areas of northwestern (NW) China, the rangeland degradation is more severe than that in pastoral areas. The HCRS is difficult to implement because the limited and fragmented grazing land cannot be contracted to individual households. Thus the pastures in the agro-pastoral areas are grazed as communal pastoral land and the rate of rangeland degradation has accelerated as livestock numbers have grown. Several measures have been introduced in an attempt to reverse this degradation trend, but most failed. This paper reports a 5-year comparison of three rangeland management regimens, including the national “Protecting rangeland by restricting grazing” (PRRG) project under the individual HCRS (PRRG under IHCRS), the Allied Householders Contract Responsibility System (AHCRS) program funded by the World Bank/GEF, and the free grazing on common pasture as the control area (CA) at Mayinggou Village, Yongchang County, Gansu Province in NW China. The results showed significant differences (P < 0.05) between AHCRS and the other two regimens (PRRG under IHCRS and CA) in terms of biomass of palatable forages, cover, and plant diversity index of vegetation but no significant difference (P > 0.05) between PRRG under IHCRS and CA. Reducing the number of livestock in AHCRS also resulted in increased revenue from the livestock turn-off rate compared with that in PRRG under IHCRS and CA. Therefore, AHCRS is a better alternative management regimen for rangelands in agro-pastoral areas. AHCRS can solve the overgrazing problem, maintain or improve household income, and potentially ensure a long-term sustainable rangeland management regimen in agro-pastoral areas in NW China.

Gravel pads of powerline towers as human-made habitats for ruderal vegetation in some Mediterranean wetlands of Egypt: Implications for management

Despite the widespread of transmission powerlines in many aquatic ecosystems of Egypt, little is known about their ecological impacts. The current study evaluates floristic composition associated with gravel pads constructed for stabilizing powerline towers in the wetlands of Burullus and Manzala. Plant cover was measured for 34 randomly selected in paired gravel pads and adjacent wetlands. Ordination analysis indicated that vegetation on the gravel pads significantly differed from that in wetlands. Thirty-two species were recorded in the gravel pad plots (more than twice the number found in wetlands). Mean species richness was significantly higher in gravel pad plots (3.8 species) than in wetland plots (1.7 species). Gravel pad plots had a significantly lower cover than wetlands of Chenopodiaceae (12.9% vs. 28.7%) and Poaceae (15.7% vs. 32.2%), while Asteraceae showed higher cover in gravel pad plots (25%) than in wetlands (6.7%). Gravel pad plots were consistently occupied by ruderals, weeds and invasive species. Regression analysis showed that total vegetation cover and diversity indices increased significantly with rises in the thickness of the gravel pads. The study highlighted the importance of gravel pad corridors for the abundance of ruderal plant species that could eventually colonize more pristine areas in the adjacent wetlands.

Vegetation dynamics of &lt;i&gt;Triarrhena sacchariflora&lt;/i&gt; and &lt;i&gt;Carex&lt;/i&gt; sp. community ecotone and determining factors in Lake Dongting:A case study in the Beizhouzi lake-shore

近年来,受全球变化及高强度人类活动的影响,洞庭湖湿地群落分布带不断下移,引发了人们对其湿地服务功能下降的担忧.以洞庭湖北洲子洲滩为例,采用野外样带调查和室内分析相结合的方法,对洞庭湖湿地荻-苔草群落交错带植被和环境特征进行研究,以期揭示荻-苔草群落交错带动态变化和影响其变化的关键环境因子.结果表明:土壤含水量随高程增加呈逐渐降低的趋势,土壤总碳、总氮、总磷含量和pH值在样带间差异显著,但土壤电导率和总钾含量在样带间无显著差异.各样带物种丰富度和香农指数随高程增加整体上呈先降低再增加的趋势.荻生物量随高程增加呈逐渐增加的趋势,而苔草生物量呈先增加后减少的趋势.典型相关分析表明,土壤含水量与二者生物量及群落丰富度、多样性间具有很好的相关性,表明土壤含水量是调控该群落交错带植被动态变化的关键环境因子.;In recent years, the vegetation distribution decreased significantly in Lake Dongting due to global change and intensive human disturbance, and has induced significant concerning about the decrement of service functions. In order to reveal the vegetation dynamics and its dominant influencing factors of Triarrhena sacchariflora and Carex sp.community ecotone, we took Beizhouzi lake-shore as an example, and investigated the vegetation characteristics and soil environmental characteristics in the ecotone of T. sacchariflora and Carex sp.community in the Lake Dongting based on belt sampling method and indoor measurement. The results showed that: soil moisture decreased significantly along with increment of elevation. Total carbon, total nitrogen, total phosphorus and pH had significant difference between these belts, while conductivity and total potassium displayed similar patterns. Vegetation species richness and diversity index decreased firstly and then increased along with elevation. Biomass of T. sacchariflora increased significantly along with elevation, while biomass of Carex sp.community exhibited increase firstly, followed by decrease with elevation. Canonical correlation analysis showed that soil moisture was significantly correlated with both biomass accumulation of T. sacchariflora and Carex sp., and vegetation species richness and diversity, indicating that soil moisture is the key dominant factor influencing vegetation dynamics in this ecotone.

Study of temporal variation of vegetation indices and phenology of tropical deciduous broadleaf forest in eastern India

Abstract. In the recent years study of vegetation variation has taken significance as a quintessential part of a bigger research agenda of climate change. This study has attempted to (a) Analyse the inter-annual and seasonal variation of vegetation (b) Observe the variation in phenological transition dates of tropical deciduous broadleaf forest (DBF) in Eastern India from 2003 to 2012. The study was conducted on 1500 sq. km area of dense forest in the districts of West Singhbhum and Sundargarh. MODIS EVI data of 250 meter resolution was used. Land cover mask was used to study only the DBF pixels. Least squares convolution method proposed by Savitzky and Golay was used for noise reduction and smoothing. For the determination of phenological parameters iterative Savitzky-Golay method followed by threshold method was used in TIMESAT software. The results showed that (i) EVI varied between 0.41 in early April and 0.71 in mid October (ii) The overall trend was decreasing with a slope of 0.0022, representing a degradation trend (iii) EVI of summer season was found to be more stable than of rainy and winter season (iv) Summer and rainy months showed a decreasing trend whereas the winter months showed an overall increase (v) Day of start of season varied between 2nd May and 20th June whereas the day of end of season varied between 1st February and 7th March (vi) Length of season was longest for 2007 at 302 days and shortest for 2010 at 235 days and showed an overall decreasing trend.

Pan-European Grassland Mapping Using Seasonal Statistics From Multisensor Image Time Series

Grasslands cover approximately 40% of the Earth’s surface. Low-cost tools for inventory, management, and monitoring are needed because of their great expanse, diversity, and the importance for environmental processes. Remote sensing is a useful technique for providing accurate and reliable information for land use planning and large-scale grassland management. In the context of “GIO land” (Copernicus Initial Operations land program), which is currently contracted by the European Environment Agency, a high-resolution grassland layer of 39 European countries is being created with an overall classification accuracy of better than 80%. Since grassland canopy density, chlorophyll status, and ground cover (GC) are highly dynamic throughout the growing season, no unique spectral signature can be used to map grasslands. Therefore, it is necessary to use image time series to characterize the phenological dynamics of grasslands throughout the year in order to discriminate between grasslands and other vegetation with similar spectral responses. This paper describes an operational approach based on a multisensor concept that employs optical multitemporal and multiscale satellite imagery to generate the high-resolution pan- European grassland layer. The approach is based on the supervised decision tree classifier C5.0 in combination with previous image segmentation and seasonal statistics for various vegetation indices (VIs). Results from the grassland classification for Hungary are presented. The accuracy assessment for this classification was carried out using 328 independent sample points derived from a ground-based European field survey program (LUCAS) and current CORINE Land Cover data. The grassland classification approach is explained in detail on the example of Hungary where an overall accuracy of 92.2% has been reached.