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Full-Text Articles in Remote Sensing

High-Resolution Monitoring Of Intra-Seasonal Agricultural Drought Using Sentinel-2 And Machine Learning Across Bimodal Growing Seasons In Kenya, S. Mohammad Mirmazloumi, Harison Kipkulei, Rose Waswa, Tobias Landmann, Tom Dienya, Maximilian Schwarz, Fabrizio Ramoino, Clément Albergel, Gohar Ghazaryan Apr 2026

High-Resolution Monitoring Of Intra-Seasonal Agricultural Drought Using Sentinel-2 And Machine Learning Across Bimodal Growing Seasons In Kenya, S. Mohammad Mirmazloumi, Harison Kipkulei, Rose Waswa, Tobias Landmann, Tom Dienya, Maximilian Schwarz, Fabrizio Ramoino, Clément Albergel, Gohar Ghazaryan

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Drought presents significant challenges to agriculture, threatening food security and livelihoods, across many regions. In Kenya, recurrent droughts across diverse agro-ecological zones emphasize the urgent need for reliable and scalable drought assessment methods. Although drought assessment with various datasets has been carried out for this region, many of them often use course or moderate resolution data. This study uses high-resolution Sentinel-2 observations and machine learning to monitor intra-seasonal crop conditions and assess drought impacts across bimodal growing seasons. Using pixel-based supervised random forest models trained with multiple vegetation indices as input, we classify croplands into drought-affected and unaffected areas. The …


Mapping Robusta Coffee (Coffea Canephora) Cropping Systems In Uganda: A Two-Step Pixel And Sub-Pixel Based Approach With Sentinel-2 Data, Getachew Kebede, Bester Tawona Mudereri, Onisimo Mutanga, Tobias Landmann, John Odindi, Natacha Motisi, Fabrice Pinard, Henri E.Z. Tonnang, Elfatih M. Abdel-Rahman Jan 2026

Mapping Robusta Coffee (Coffea Canephora) Cropping Systems In Uganda: A Two-Step Pixel And Sub-Pixel Based Approach With Sentinel-2 Data, Getachew Kebede, Bester Tawona Mudereri, Onisimo Mutanga, Tobias Landmann, John Odindi, Natacha Motisi, Fabrice Pinard, Henri E.Z. Tonnang, Elfatih M. Abdel-Rahman

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Coffee is a highly valued commodity and a widely consumed beverage, playing an important role in global trade. However, coffee farming landscapes are increasing transitioning into smaller-scale agricultural setups. This transformation highlights the critical need for accurate classification and mapping of coffee cropping systems (CS), especially in countries like Uganda, where dense vegetation and complex terrain present substantial challenges to traditional land survey methods. Moreover, understanding the spatial distribution of Robusta coffee (Coffea canephora) CS is essential for developing site-specific management strategies, guiding extension services, and informing evidence-based policy decisions. To address this gap, the present study aimed to enhance …


Spatiotemporal Trends In Anopheles Funestus Breeding Habitats, Grace R. Aduvukha, Elfatih M. Abdel-Rahman, Bester Tawona Mudereri, Onisimo Mutanga, John Odindi, Henri E.Z. Tonnang Feb 2025

Spatiotemporal Trends In Anopheles Funestus Breeding Habitats, Grace R. Aduvukha, Elfatih M. Abdel-Rahman, Bester Tawona Mudereri, Onisimo Mutanga, John Odindi, Henri E.Z. Tonnang

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Effective identification and control of malaria vector larval breeding habitats are crucial for the management and eradication of malaria. Despite its importance, the last decade has seen a decline in data availability and intervention efforts due to reduced attention and prioritization. This study addresses the geographic data scarcity concerning Anopheles funestus larval breeding habitats in a malaria-prone region of western Kenya. Employing a two-step methodological approach, we integrated multi-criteria decision analysis (MCDA) and rule-based fuzzy logic analysis to evaluate the spatiotemporal similarity or divergence of these habitats. The analysis spanned a five-year interval, 2008, 2013, and 2018 with 2013 serving …


Earth Observations Reveal Impacts Of Climate Variability On Maize Cropping Systems In Sub-Saharan Africa, Adomas Liepa, Michael Thiel, Hannes Taubenböck, Doris Klein, Ingolf Steffan-Dewenter, Marcell K. Peters, Sarah Schönbrodt-Stitt, Insa Otte, Tobias Landmann, Zeyaur R. Khan, Michael Ochieng Obondo, Frank Chidawanyika, Emily A. Martin, Tobias Ullmann Jan 2025

Earth Observations Reveal Impacts Of Climate Variability On Maize Cropping Systems In Sub-Saharan Africa, Adomas Liepa, Michael Thiel, Hannes Taubenböck, Doris Klein, Ingolf Steffan-Dewenter, Marcell K. Peters, Sarah Schönbrodt-Stitt, Insa Otte, Tobias Landmann, Zeyaur R. Khan, Michael Ochieng Obondo, Frank Chidawanyika, Emily A. Martin, Tobias Ullmann

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In Kenya, climate variability and change threaten smallholder, rainfed farms, with crop failures, yield reductions, and pest infestations. Efficient agroecological strategies, such as Push-Pull intercropping, offer documented benefits including pest control, improved soil fertility, and water conservation compared to traditional maize monocropping. To date, no studies exist comparing traditional maize monocropping and Push-Pull intercropping using earth observation tools over several growing seasons in East Africa. Our research addresses this by harmonizing Landsat 7, 8, 9 with Sentinel-2 remote sensing time series from 2016 to 2023. Phenological metrics of 15 growing seasons are extracted based on a threshold method using the …


Annual Diversity Of Honey Bee Pollen Sources In Two Pumpkin Growing Landscapes, Machakos County, Kenya, Marystella W. Nang’Oni, Muo Kasina, Rebecca Karanja, Mary M. Guantai, Rahab N. Kinyanjui, Evanson R. Omuse, Michael H.G. Lattorff, Elfatih M. Abdel-Rahman, Marian Adan, Samira A. Mohamed, Thomas Dubois Jan 2025

Annual Diversity Of Honey Bee Pollen Sources In Two Pumpkin Growing Landscapes, Machakos County, Kenya, Marystella W. Nang’Oni, Muo Kasina, Rebecca Karanja, Mary M. Guantai, Rahab N. Kinyanjui, Evanson R. Omuse, Michael H.G. Lattorff, Elfatih M. Abdel-Rahman, Marian Adan, Samira A. Mohamed, Thomas Dubois

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Multi-floral foraging sources for honey bee (Apis mellifera L.) have been threatened by landscape changes and unsustainable farming practices. In East Africa, the biodiversity of forage resources that could support honey bees, especially in agricultural lands, remains least explored. This study investigated pollen diversity for honey bees in Yatta and Masinga Sub-counties in Machakos County, Kenya. Honey bee hives were installed on eight pumpkin (Cucurbita maxima Duchesne ex Lam) farms (one hive per farm) in two varying landscape vegetation classes (low and medium) based on normalized difference vegetation index (NDVI). Pollen traps were installed at the hive entrance and pollen …


The Possibilities Of Explicit Striga (Striga Asiatica) Risk Monitoring Using Phenometric, Edaphic, And Climatic Variables, Demonstrated For Malawi And Zambia, Emily Kimathi, Bester Tawona Mudereri, Elfatih M. Abdel-Rahman, Saliou Niassy, Henri E.Z. Tonnang, Tobias Landmann Dec 2022

The Possibilities Of Explicit Striga (Striga Asiatica) Risk Monitoring Using Phenometric, Edaphic, And Climatic Variables, Demonstrated For Malawi And Zambia, Emily Kimathi, Bester Tawona Mudereri, Elfatih M. Abdel-Rahman, Saliou Niassy, Henri E.Z. Tonnang, Tobias Landmann

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Food insecurity continues to affect more than two-thirds of the population in sub‐Saharan Africa (SSA), particularly those depending on rain-fed agriculture. Striga, a parasitic weed, has caused yield losses of cereal crops, immensely affecting smallholder farmers in SSA. Although earlier studies have established that Striga is a constraint to crop production, there is little information on the spatial extent of spread and infestation severity of the weed in some SSA countries like Malawi and Zambia. This study aimed to use remotely sensed vegetation phenological (n = 11), climatic (n = 3), and soil (n = 4) variables to develop a …


Malaria Vector Feeding, Peak Biting Time And Resting Place Preference Behaviors In Line With Indoor Based Intervention Tools And Its Implication: Scenario From Selected Sentinel Sites Of Ethiopia, Alemnesh Hailemariam Bedasso, Abebe Asale Gutto, Abate Waldetensai, Araya Eukubay, Getachew Eticha Bokore, Solomon Kinde, Fekadu Gemechu, Yared Debebe, Mesfin Aklilu, Geremew Tasew, Fekadu Massebo, Abebe Teshome, Tilahun Kebede, Bedri Abdulatif, Achamyelesh Sisay, Hiwot Solomon, Eliningaya J. Kweka Dec 2022

Malaria Vector Feeding, Peak Biting Time And Resting Place Preference Behaviors In Line With Indoor Based Intervention Tools And Its Implication: Scenario From Selected Sentinel Sites Of Ethiopia, Alemnesh Hailemariam Bedasso, Abebe Asale Gutto, Abate Waldetensai, Araya Eukubay, Getachew Eticha Bokore, Solomon Kinde, Fekadu Gemechu, Yared Debebe, Mesfin Aklilu, Geremew Tasew, Fekadu Massebo, Abebe Teshome, Tilahun Kebede, Bedri Abdulatif, Achamyelesh Sisay, Hiwot Solomon, Eliningaya J. Kweka

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In Ethiopia, malaria incidence has significantly reduced in the past decade through the combined use of conventional vector control approaches and treatment using antimalarial drugs. However, the sustainability of this achievement is threatened by the shift in biting and resting behaviors and emergence of insecticide resistance by the primary malaria vector. Therefore, continuous monitoring of the behaviour of malaria mosquitoes in different sentinel sites is crucial to design effective prevention and control methods in the local context. Entomological investigations were conducted in three sentinel sites for five consecutive months during the major malaria transmission season. The species composition, population dynamics, …


Pollinator Supplementation Mitigates Pollination Deficits In Smallholder Avocado (Persea Americana Mill.) Production Systems In Kenya, Rose Nyakemiso Sagwe, Marcell K. Peters, Thomas Dubois, Ingolf Steffan-Dewenter, H. Michael G. Lattorff Nov 2021

Pollinator Supplementation Mitigates Pollination Deficits In Smallholder Avocado (Persea Americana Mill.) Production Systems In Kenya, Rose Nyakemiso Sagwe, Marcell K. Peters, Thomas Dubois, Ingolf Steffan-Dewenter, H. Michael G. Lattorff

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Avocado (Persea americana Mill.) is a major horticultural crop that relies on insect mediated pollination. In avocado production, a knowledge gap exists as to the importance of insect pollination, especially in East African smallholder farms. In this study, conducted in a leading smallholder avocado production region in Kenya, we assessed the dependence of avocado fruit set on insect pollination and whether current smallholder production systems suffer from a deficit in pollination services. Furthermore, we assessed if supplementation with colonies of the Western honey bee (Apis mellifera L.) to farms mitigated potential pollination deficits. Our results revealed a very high reliance …


Use Of Earth Observation Satellite Data To Guide The Implementation Of Integrated Pest And Pollinator Management (Ippm) Technologies In An Avocado Production System, Marian Adan, Elfatih M. Abdel-Rahman, Stella Gachoki, Beatrice W. Muriithi, H. Michael G. Lattorff, Vivian Kerubo, Tobias Landmann, Samira A. Mohamed, Henri E.Z. Tonnang, Thomas Dubois Aug 2021

Use Of Earth Observation Satellite Data To Guide The Implementation Of Integrated Pest And Pollinator Management (Ippm) Technologies In An Avocado Production System, Marian Adan, Elfatih M. Abdel-Rahman, Stella Gachoki, Beatrice W. Muriithi, H. Michael G. Lattorff, Vivian Kerubo, Tobias Landmann, Samira A. Mohamed, Henri E.Z. Tonnang, Thomas Dubois

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Insect pollinators provide an important ecosystem service by improving agricultural productivity. However, their populations have been declining in recent years due to excessive use of synthetic pesticides, climate and land use/land cover (LULC) changes. Climate and LULC changes have resulted in land fragmentation and consequently pollinator habitat loss. To conserve pollinators, there is a need for sustainable agricultural practices such as integrated pest and pollinator management (IPPM), which is a holistic landscape management approach that minimizes pesticides use while conserving pollinator abundance and diversity. This study aimed to use earth observation (EO) data to characterize landscape dynamics in terms of …


Leveraging Of Hyperspectral Remote Sensing On Estimating Biomass Yield Of Moringa Oleifera Lam. Medicinal Plant, Thulani Tshabalala, Elfatih M. Abdel-Rahman, Bhekumthetho Ncube, Ashwell R. Ndhlala, Onisimo Mutanga Aug 2021

Leveraging Of Hyperspectral Remote Sensing On Estimating Biomass Yield Of Moringa Oleifera Lam. Medicinal Plant, Thulani Tshabalala, Elfatih M. Abdel-Rahman, Bhekumthetho Ncube, Ashwell R. Ndhlala, Onisimo Mutanga

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Moringa oleifera Lam. is a functional plant considered to be high in nutrients as well as medicinal properties, largely utilised in most of the developing countries. Therefore, early prediction of M. oleifera biomass yield is a valuable pre- and post-harvest planning strategy for ensuring a reliable supply of the plant products and for marketing purposes. Subsequently, the objective of the current study was to explore the potential use of hyperspectral data in predicting biomass yield of different cultivars of M. oleifera. Canopy hyperspectral data were collected on five M. oleifera cultivars when they were one month and two months old …


Landscape Fragmentation In Coffee Agroecological Subzones In Central Kenya: A Multiscale Remote Sensing Approach, Gladys Mosomtai, John Odindi, Elfatih M. Abdel-Rahman, Régis Babin, Pinard Fabrice, Onisimo Mutanga, Henri E.Z. Tonnang, Guillaume David, Tobias Landmann Oct 2020

Landscape Fragmentation In Coffee Agroecological Subzones In Central Kenya: A Multiscale Remote Sensing Approach, Gladys Mosomtai, John Odindi, Elfatih M. Abdel-Rahman, Régis Babin, Pinard Fabrice, Onisimo Mutanga, Henri E.Z. Tonnang, Guillaume David, Tobias Landmann

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Smallholder agroecological subzones (AEsZs) produce an array of crops occupying large areas throughout Africa but remain largely unmapped. We explored multisource satellite datasets to produce a seamless land-use and land-cover (LULC) and fragmentation dataset for upper midland (UM1 to UM4) AEsZs in central Kenya. Specifically, the utility of PlanetScope, Sentinel 2, and Landsat 8 images for mapping coffee-based landscape were tested using a random forest (RF) classifier. Vegetation indices, texture variables, and wavelength bands from all satellite data were used as inputs in generating four RF models. A LULC baseline map was produced that was further analyzed using FRAGSTAT to …


Phenology Of Short Vegetation Cycles In A Kenyan Rangeland From Planetscope And Sentinel-2, Yan Cheng, Anton Vrieling, Francesco Fava, Michele Meroni, Michael Marshall, Stella Gachoki Oct 2020

Phenology Of Short Vegetation Cycles In A Kenyan Rangeland From Planetscope And Sentinel-2, Yan Cheng, Anton Vrieling, Francesco Fava, Michele Meroni, Michael Marshall, Stella Gachoki

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The short revisit times afforded by recently-deployed optical satellite sensors that acquire 3–30 m resolution imagery provide new opportunities to study seasonal vegetation dynamics. Previous studies demonstrated a successful retrieval of phenology with Sentinel-2 for relatively stable annual growing seasons. In semi-arid East Africa however, vegetation responds rapidly to a concentration of rainfall over short periods and consequently is subject to strong interannual variability. Obtaining a sufficient density of cloud-free acquisitions to accurately describe these short vegetation cycles is therefore challenging. The objective of this study is to evaluate if data from two satellite constellations, i.e., PlanetScope (3 m resolution) …


Potential Of Resampled Multispectral Data For Detecting Desmodium-Brachiaria Intercropped With Maize In A 'Push-Pull' System, B. T. Mudereri, E. M. Abdel-Rahman, T. Dube, T. Landmann, S. Niassy, H. E.Z. Tonnang, Z. R. Khan Aug 2020

Potential Of Resampled Multispectral Data For Detecting Desmodium-Brachiaria Intercropped With Maize In A 'Push-Pull' System, B. T. Mudereri, E. M. Abdel-Rahman, T. Dube, T. Landmann, S. Niassy, H. E.Z. Tonnang, Z. R. Khan

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Poor crop yields remain one of the main causes of chronic food insecurity in Africa. This is largely caused by insect pests, weeds, unfavourable climatic conditions and degraded soils. Weed and pest control, based on the climate-adapted g'push-pull' system, has become an important target for sustainable intensification of food production adopted by many small-holder farmers. However, essential baseline information using remotely sensed data is missing, specifically for the g'push-pull' companion crops. In this study, we investigated the spectral uniqueness of two of the most commonly used g'companion' crops (i.e. greenleaf Desmodium (i Desmodium intortum/i) and Brachiaria (i Brachiaria/i cv Mulato) …


Is It Possible To Discern Striga Weed (Striga Hermonthica) Infestation Levels In Maize Agro-Ecological Systems Using In-Situ Spectroscopy?, Bester Tawona Mudereri, Timothy Dube, Saliou Niassy, Emily Kimathi, Tobias Landmann, Zeyaur Khan, Elfatih M. Abdel-Rahman Mar 2020

Is It Possible To Discern Striga Weed (Striga Hermonthica) Infestation Levels In Maize Agro-Ecological Systems Using In-Situ Spectroscopy?, Bester Tawona Mudereri, Timothy Dube, Saliou Niassy, Emily Kimathi, Tobias Landmann, Zeyaur Khan, Elfatih M. Abdel-Rahman

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The invasion by Striga in most cereal crop fields in Africa has posed a significant threat to food security and has caused substantial socioeconomic losses. Hyperspectral remote sensing is an effective means to discriminate plant species, providing possibilities to track such weed invasions and improve precision agriculture. However, essential baseline information using remotely sensed data is missing, specifically for the Striga weed in Africa. In this study, we investigated the spectral uniqueness of Striga compared to other co-occurring maize crops and weeds. We used the in-situ FieldSpec® Handheld 2™ analytical spectral device (ASD), hyperspectral data and their respective narrow-band indices …


Predicting The Spatial Suitability Distribution Of Moringa Oleifera Cultivation Using Analytical Hierarchical Process Modelling, T. Tshabalala, B. Ncube, H. P. Moyo, E. M. Abdel-Rahman, O. Mutanga, A. R. Ndhlala Mar 2020

Predicting The Spatial Suitability Distribution Of Moringa Oleifera Cultivation Using Analytical Hierarchical Process Modelling, T. Tshabalala, B. Ncube, H. P. Moyo, E. M. Abdel-Rahman, O. Mutanga, A. R. Ndhlala

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Moringa oleifera Lam, often grows well under cultivation in the tropics and sub-tropics. It does well in sandy to clayey soils and tolerates low rainfall. The plant is well-known for its nutritional and medicinal properties, hence it is fast gaining popularity in South Africa and the rest of the world. The objective of this study was to predict the suitable areas for cultivating M. oleifera in South Africa using climate and edaphic variables that significantly affect its growth and development. We used an Analytical Hierarchical Process (AHP) and Geographic Information System (GIS) weight function to assign suitability weights to criteria …


A Comparative Analysis Of Planetscope And Sentinel Sentinel-2 Space-Borne Sensors In Mapping Striga Weed Using Guided Regularised Random Forest Classification Ensemble, B. T. Mudereri, T. Dube, E. M. Adel-Rahman, S. Niassy, E. Kimathi, Z. Khan, T. Landmann Jun 2019

A Comparative Analysis Of Planetscope And Sentinel Sentinel-2 Space-Borne Sensors In Mapping Striga Weed Using Guided Regularised Random Forest Classification Ensemble, B. T. Mudereri, T. Dube, E. M. Adel-Rahman, S. Niassy, E. Kimathi, Z. Khan, T. Landmann

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Weeds are one of the major restrictions to sustaining crop productivity. Weeds often outcompete crops for nutrients, soil moisture, solar radiation, space and provide platforms for breeding of pests and diseases. The ever-growing global food insecurity triggers the need for spatially explicit innovative geospatial technologies that can deliver timely detection of weeds within agro-ecological systems. This will help pinpoint maize fields to be prioritized for weed control. Satellite remote sensing offers incomparable opportunities for precision agriculture, ecological applications and vegetation characterisation, with vast socioeconomic benefits. This work compares and evaluates the strength of Sentinel-2 (S2) satellite with the constellation of …


Sustainable Recommendation Domains For Scaling Agricultural Technologies In Tanzania, Francis K. Muthoni, Zhe Guo, Mateete Bekunda, Haroon Sseguya, Fred Kizito, Frederick Baijukya, Irmgard Hoeschle-Zeledon Jul 2017

Sustainable Recommendation Domains For Scaling Agricultural Technologies In Tanzania, Francis K. Muthoni, Zhe Guo, Mateete Bekunda, Haroon Sseguya, Fred Kizito, Frederick Baijukya, Irmgard Hoeschle-Zeledon

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Low adoption of sustainable intensification technologies hinders achievement of their potential impacts on increasing agricultural productivity. Proper targeting of locations to scale-out particular technologies is a key determinant of the rate of adoption. Targeting locations with similar biophysical and socio-economic characteristics significantly increases the probability of adoption. Areas with similar biophysical and socio-economic characteristics are referred to as recommendation domains (RDs). This study used geospatial analysis to delineate sustainable recommendation domains (SRDs) for scaling improved crop varieties and good agronomic practices in Tanzania. The study uses K-means clustering to identify relatively similar clusters from grid raster's representing biophysical and socio-economic …


Analysing Chemical Attraction Of Gravid Anopheles Gambiae Sensu Stricto With Modified Bg-Sentinel Traps, Michael N. Okal, Manuela Herrera-Varela, Paul Ouma, Baldwyn Torto, Steven W. Lindsay, Jenny M. Lindh, Ulrike Fillinger Jun 2015

Analysing Chemical Attraction Of Gravid Anopheles Gambiae Sensu Stricto With Modified Bg-Sentinel Traps, Michael N. Okal, Manuela Herrera-Varela, Paul Ouma, Baldwyn Torto, Steven W. Lindsay, Jenny M. Lindh, Ulrike Fillinger

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Background: Cues that guide gravid Anopheles gambiae sensu lato to oviposition sites can be manipulated to create new strategies for monitoring and controlling malaria vectors. However, progress towards identifying such cues is slow in part due to the lack of appropriate tools for investigating long-range attraction to putative oviposition substrates. This study aimed to develop a relatively easy-to-use bioassay system that can effectively analyse chemical attraction of gravid Anopheles gambiae sensu stricto. Methods: BG-Sentinel™ mosquito traps that use fans to dispense odourants were modified to contain aqueous substrates. Choice tests with two identical traps set in an 80 m2 screened …


Predicting The Impact Of Climate Change On Regional And Seasonal Abundance Of The Mealybug Phenacoccus Solenopsis Tinsley (Hemiptera: Pseudococcidae) Using Temperature-Driven Phenology Model Linked To Gis, Babasaheb B. Fand, Henri E.Z. Tonnang, Mahesh Kumar, Santanu K. Bal, Naveen P. Singh, D. V.K.N. Rao, Ankush L. Kamble, Dhananjay D. Nangare, Paramjit S. Minhas Sep 2014

Predicting The Impact Of Climate Change On Regional And Seasonal Abundance Of The Mealybug Phenacoccus Solenopsis Tinsley (Hemiptera: Pseudococcidae) Using Temperature-Driven Phenology Model Linked To Gis, Babasaheb B. Fand, Henri E.Z. Tonnang, Mahesh Kumar, Santanu K. Bal, Naveen P. Singh, D. V.K.N. Rao, Ankush L. Kamble, Dhananjay D. Nangare, Paramjit S. Minhas

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The mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is a highly invasive and polyphagous pest of global incidence. The fundamental hypothesis of the present study was that the temperature variations due to global climate change may affect seriously the future distribution and abundance of P. solenopsis, which might further aggravate the crop yield losses. We employed a temperature-based phenology model of P. solenopsis in a geographic information system for mapping population growth potentials of P. solenopsis. The three risk indices viz., establishment risk index, generation index and activity index were computed using interpolated temperature data from worldclim database for current (2000) …


Spatial Analysis Of Human-Induced Vegetation Productivity Decline Over Eastern Africa Using A Decade (2001-2011) Of Medium Resolution Modis Time-Series Data, Tobias Landmann, Olena Dubovyk Jan 2014

Spatial Analysis Of Human-Induced Vegetation Productivity Decline Over Eastern Africa Using A Decade (2001-2011) Of Medium Resolution Modis Time-Series Data, Tobias Landmann, Olena Dubovyk

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Climate variation and land transformations related to exploitative land uses are among the main drivers of vegetation productivity decline and ongoing land degradation in East Africa. We combined analysis of vegetation trends and cumulative rain use efficiency differences (CRD), calculated from 250-m MODISNDVI time-series data, to map vegetation productivity loss over eastern Africa between 2001 and 2011.The CRD index values were furthermore used to discern areas of particular severe vegetation productivity loss over the observation period. Monthly 25-km Tropical Rainfall Measuring Mission (TRMM) datametrics were used to mask areas of rainfall declines not related to human-induced land productivity loss. To …


Mapping Vegetation Productivity Dynamics And Degradation Trends Over East Africa Using A Decade Of Medium Resolution Modis Time-Series Data, Tobias Landmann, Olena Dubovyk Dec 2013

Mapping Vegetation Productivity Dynamics And Degradation Trends Over East Africa Using A Decade Of Medium Resolution Modis Time-Series Data, Tobias Landmann, Olena Dubovyk

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This paper aims to characterize spatial and temporal vegetation productivity trends that could be related to land degradation in East Africa. A decade of AQUA/TERRA-Moderate Resolution Imaging Spectroradiometer (MODIS) satellite observations on vegetation chlorophyll activity, or Normalized Differential Vegetation Index (NDVI) data, and 25-km rainfall data from the TRMM passive radar instrument were used for the same observation period of 2000-2011. Linear trends in land cover based Rain Use Efficiencies (RUE) corrected NDVI and cumulative differences of RUE between consecutive years from 2000 to 2011 (that is amplitudes) were derived and investigated for their robustness. The trend maps were overlaid …