Gohar Ghazaryan

• Dr. rer. nat.
• Senior Researcher at Leibniz Centre for Agricultural Landscape Research

Drought research addresses one of the major natural hazards that threatens progress toward the Sustainable Development Goals. This study aims to map the evolution and interdisciplinarity of drought research over time and across regions, offering insights for decision-makers, researchers, and funding agencies. By analysing more than 130 000 peer-rev...

Effective management of water resources in anthropogenically shaped lowlands requires a comprehensive understanding of hydrological processes and balancing various effects in complex settings, especially like lowland hydrology. Unlike mountainous headwater catchments with shallow soils, lowland hydrology is typically dominated by groundwater dynami...

Agricultural production assessments are crucial for formulating strategies for closing yield gaps and enhancing production efficiencies. While in situ crop yield measurements can provide valuable and accurate information, such approaches are costly and lack scalability for large-scale assessments. Therefore, crop modeling and remote sensing (RS) te...

Drought research addresses a major natural hazard with adverse impacts towards achieving the sustainable development goals. Here, we analyzed more than 130,000 peer-reviewed articles indexed in Scopus, spanning from 1901 to 2022 using a generative model. The results delineate distinct shifts in research priorities. Plant genetic research for drough...

Maize (Zea mays L.) productivity in Kenya has witnessed a decline attributed to the effects of climate change and biophysical constraints. The assessment of agronomic practices across agroecological zones (AEZs) is limited by inadequate data quality, hindering a precise evaluation of maize yield on a large scale. In this study, we employed the DSSA...

Researchers and engineers have increasingly used Deep Learning (DL) for a variety of Remote Sensing (RS) tasks. However, data from local observations or via ground truth is often quite limited for training DL models, especially when these models represent key socio-environmental problems, such as the monitoring of extreme, destructive climate event...

This chapter examines improving data flow and integration in models assessing the impact of climate change on agriculture. It starts by first describing model-data integration, focusing on multi-criteria calibration of mechanistic agro-ecosystem models. The chapter moves on to review informing spatio-temporal simulations through methods such as rem...

The table data source for the review paper of Safonova et al., “Ten deep learning techniques to address small data problems with remote sensing”.

Researchers and engineers have increasingly used Deep Learning (DL) for a variety of Remote Sensing (RS) tasks. However, data from local observations or via ground truth is often quite limited for training DL models, especially when these models represent key socio-environmental problems, such as the monitoring of extreme, destructive climate event...

Climate change and a rapidly increasing population boost the pressure on Türkiye's cropping systems to increase crop production in order to meet rising food demand. It is unknown whether and in which direction trends and variability in harvested area and yield separately affect crop production in Türkiye. The objective of this study was to (1) quan...

Spatial predictions of biomass production and biodiversity at regional scale in grasslands are critical to evaluate the effects of management practices across environmental gradients. New generations of remote sensing sensors and machine learning approaches can predict these grassland characteristics with varying accuracy. However, such studies fre...

Maize production in low-yielding regions is influenced by climate variability, poor soil fertility, suboptimal agronomic practices, and biotic influences, among other limitations. Therefore, the assessment of yields to various management practices is, among others, critical for advancing site-specific measures for production enhancement. In this st...

This chapter underlines the need for interdisciplinary and transdisciplinary research to support drought risk monitoring for sustainable development using Earth observation (EO)‐based information products and socioeconomic statistics. While a large number of drought indicators already exists, clear guidance on how to embed these into policy advice...

Population growth and increasing demand for agricultural production continue to drive global cropland expansions. These expansions lead to the overexploitation of fragile ecosystems, propagating land degradation, and the loss of natural diversity. This study aimed to identify the factors driving land use/land cover changes (LULCCs) and subsequent c...

The availability of freshwater is highly influenced by climate change, extreme climate events and by anthropogenic use. Countries where a large part of the population depends on the agricultural sector, such as South Africa, are strongly affected by changes in climate, which emphasizes that water is an essential source for food production and drink...

Growing metropolitan areas have potential to affect the climate of local neighborhoods and thus become a hot topic in regional planning. The study is a contribution to the climate change related land cover simulation efforts in Germany. It investigates future land consumption rates and population growth rates keeping goal 11 of the United Nation’s...

Urban sprawl is ubiquitous with a complex network of driving forces and human and natural impacts on various scales of the coupled human-environment urban system. In Germany, a land consumption of 30 ha per day is envisaged. In that regard, the effect of growing metropolitan areas on the climate of local neighborhoods becomes more and more a topic...

The availability of freshwater is highly influenced by climate change, extreme climate events and by anthropogenic use. Countries where a large part of the population depends on the agricultural sector, such as South Africa, are strongly affected by changes in climate, which emphasizes that water is an essential source for food production and drink...

The regular drought episodes in South Africa highlight the need to reduce drought risk by both policy and local community actions. Environmental and socioeconomic factors in South Africa's agricultural system have been affected by drought in the past, creating cascading pressures on the nation's agro-economic and water supply systems. Therefore, un...

The intensification of food production systems has resulted in landscape simplification, with trees and hedges disappearing from agricultural land, principally in industrialized countries. However, more recently, the potential of agroforestry systems and small woody landscape features (SWFs), e.g., hedgerows, woodlots, and scattered groups of trees...

Political instability and economic crises may trigger informal, unsustainable and often illegal land use, leading to land degradation. One of the most recent and striking examples of such a phenomenon within Europe is demonstrated by the Polissia region in Northern Ukraine, famous for its amber deposits. Amid severe political disturbances and subse...

Increasing population and a severe water crisis impose growing pressure on cropping systems of Iran to increase crop production meeting the rising demand for food. Little is known on the separate contribution of trends and variability of the harvested area and yield on crop production in severely drought-prone areas such as Iran. In this study, we...

Monitoring land degradation (LD) to improve the measurement of the sustainable development goal (SDG) 15.3.1 indicator (“proportion of land that is degraded over a total land area”) is key to ensure a more sustainable future. Current frameworks rely on default medium-resolution remote sensing datasets available to assess LD and cannot identify subt...

By 2050, two-third of the world’s population will live in cities. In this study, we develop a framework for analyzing urban growth-related imperviousness in North Rhine-Westphalia (NRW) from the 1980s to date using Landsat data. For the baseline 2017-time step, official geodata was extracted to generate labelled data for ten classes, including thre...

One of the major sources of uncertainty in large-scale crop modeling is the lack of information capturing the spatiotemporal variability of crop sowing dates. Remote sensing can contribute to reducing such uncertainties by providing essential spatial and temporal information to crop models and improving the accuracy of yield predictions. However, l...

Drought is one of the extreme climatic events that has a severe impact on crop production and food supply. Our main goal is to test the suitability of remote sensing-based indices to detect drought impacts on crop production from a global to regional scale. Moderate resolution imaging spectroradiometer (MODIS) based imagery, spanning from 2001 to 2...

Agricultural production and food security highly depend on crop growth and condition throughout the growing season. Timely and spatially explicit information on crop phenology can assist in informed decision making and agricultural land management. Remote sensing can be a powerful tool for agricultural assessment. Remotely sensed data is ideally su...

Globally, drought constitutes a serious threat to food and water security. The complexity and multivariate nature of drought challenges its assessment, especially at local scales. The study aimed to assess spatiotemporal patterns of crop condition and drought impact at the spatial scale of field management units with a combined use of time-series f...

Achieving land degradation neutrality (LDN) has been proposed to stem the loss of land resources globally. To date, LDN operationalization at country level has remained a challenge both from a policy and science perspective. Using an approach incorporating cloud‐based geospatial computing with machine learning, national level datasets of land cover...

Abstract—Drought is one of the most severe natural disasters with a high risk for human livelihoods. Remote sensing based drought indices can identify dry periods using, e.g., precipitation or vegetation information. Besides frequency, duration, and intensity, the timing of a drought onset and duration are important variables to measure the drought...

Invasive plant species in eastern Africa severely impede rangeland and cropland productivity with dire consequences for livelihoods of agro-pastoralist communities. We produced the first occurrence and spread map of invasive plant species (Prosopis: Prosopis juliflora and Parthenium: Parthenium hysterophorus) for western Somaliland (a region of eas...

Droughts have significant negative impacts on livelihoods and economy of Kazakhstan. In this study, we assessed and characterized drought hazard events in Kazakhstan using satellite Remote Sensing time series for the period between 2000 and 2016. First, we calculated Vegetation Condition Index (VCI) and Standardized Enhanced Vegetation Index anomal...

Climate change, food insecurity and limited land and water resources strengthen the need for operational and spatially explicit information on vegetation condition and dynamics. The detection of vegetation condition as well as multiannual and seasonal changes using satellite remote sensing, however, depends on the choice of data including length an...

Accurate classification and mapping of crops is essential for supporting sustainable land management. Such maps can be created based on satellite remote sensing; however, the selection of input data and optimal classifier algorithm still needs to be addressed especially for areas where field data is scarce. We exploited the intra-annual variation o...

Eastern Cape Province in South Africa has experienced extreme drought events during the last decade. In South Africa, different land management systems exist belonging to two different land tenure classes: commercial large scale farming and communal small-scale subsistence farming. Communal lands are often reported to be affected by land degradatio...

Invasive species (namely Prosopis juliflora and Parthenium hysterophorus) significantly impede rangeland and cropland productivity in Somaliland impacting the livelihoods of thousands of agro-pastoralists. Invasive species propagate well in overgrazed and poorly managed sites while their encroachment enables further land degradation processes such...

Abstract Invasive species and deforestation are significant land degradation factors in eastern Africa that in unity severely impede rangeland and cropland productivity with dire consequences for livelihoods of agropastoralist communities. Using 250‐meter Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data and trends computed from...

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Abstract: Ukraine has experienced immense environmental and institutional changes during the last three decades. We have conducted this study to analyze important land surface dynamics and to assess processes underlying the changes. This research was conducted in two consecutive steps. To analyze monotonic changes we first applied a Mann–Kendall tr...