Wanxue Zhu

• Doctor of Philosophy
• University of Göttingen

Leaf chlorophyll content (LCC) is a crucial indicator of nutrition in crop plants and can be applied to assess the adequacy of nitrogen (N) fertilizer for crops while reducing N losses to farmland. This study estimated the LCC of maize and wheat, and comprehensively examined the effects of the spectral information and spatial scale of unmanned aeri...

Unmanned aerial vehicle (UAV) remote sensing and machine learning have emerged as a practical approach with ultra-high temporal and spatial resolutions to overcome the limitations of ground-based sampling for continuous crop monitoring. However, little is known on the suitability of distinct sensing indices for different crop management and distinc...

Optical unmanned aerial vehicle (UAV) remote sensing is widely prevalent to estimate crop aboveground biomass (AGB). Nevertheless, limited knowledge of the UAV flight height (mainly characterized by different image numbers and spatial resolutions) influences the crop AGB estimation accuracy across diverse sensing datasets and machine/deep learning...

Irrigation profoundly impacts ecology and agricultural productivity, with irrigated areas varying across regions and years. Interannual dynamics of irrigation extent are lacking, particularly in humid regions of Europe. We analyzed the response of irrigated areas to drought conditions in areas equipped for irrigation and used the derived relationsh...

Improving crop yield and stability is crucial for sustainable food production, which is predominantly influenced by climate. Nutrient management mitigates the negative impacts of climate change on yield stability, but little is known about the explanatory capability of climate variables (especially canopy, soil, and nighttime temperatures) and soil...

Current techniques to estimate crop aboveground biomass (AGB) across the multiple growth stages mainly used optical remote-sensing techniques. However, this technology was limited by saturation of the canopy spectrum. To meet this problem, this study used digital images obtained by an unmanned aerial vehicle to extract the spectral and structural i...

Increasing crop nitrogen use efficiency (NUE) has important implications for food security and agricultural sustainability. Changes in nutrient availability due to stoichiometric imbalances in soil under long-term application of nitrogen (N) can limit crop NUE and yield. However, little is known about the linkages across stoichiometric balance, N f...

A non-destructive, convenient, and low-cost yield estimation at the field scale is vital for precision farming. Significant progress has been made in using UAV-based canopy features to predict crop yield during the mid-growth stages. However, there has been limited effort to explore yield estimation specifically after crop maturity. Researching the...

Salt-affected arable land is distributed widely in China, especially in the North China Plain. Crop residue management under appropriate tillage is critical to improving salt-affected soil organic carbon and reducing the carbon footprint. This study conducted four-year field experiments including two treatments (residue incorporated into soil with...

Soil salinization, which occurs mainly in arid and coastal regions, hampers agricultural development, and threatens food security in these regions. Therefore, acquiring the spatial distribution of soil salinization with high accuracy is paramount. However, obstacles continue to hinder attempts to use satellite remote sensing. Cyclone Global Navigat...

Accurate and in-time monitoring of cropping systems is critical to precision farming in order to facilitate decision-making for agronomic management and enhancing crop yield under changing climate. In this study, multi-source unmanned aerial vehicle (UAV) remote sensing observations were conducted at several key growing stages of crops at a standar...

As one of the most promising climate adaptation measures, rooftop mitigation strategies (RMSs) have been studied and practiced in many cities. However, the cooling potential of RMSs may be controversial under different climates. This study establishes city-scale numerical simulations of RMSs, including green roofs (GRs), cool roofs (CRs), rooftop p...

Plant density is a significant variable in crop growth. Plant density estimation by combining unmanned aerial vehicles (UAVs) and deep learning algorithms is a well-established procedure. However, flight companies for wheat density estimation are typically executed at early development stages. Further exploration is required to estimate the wheat p...

Most of the experimental and modeling studies that evaluate the impacts of climate change and variability on barley have been focused on grain yield. However, little is known on the effects of combined change in temperature, CO2 concentration, and extreme events on barley grain quality and how capable are the current process-based crop models captu...

Accurate estimation of above-ground biomass (AGB) plays a significant role in characterizing crop growth status. In precision agriculture area, a widely-used method for measuring AGB is to develop regression relationships between AGB and agronomic traits extracted from multi-source remotely sensed images based on unmanned aerial vehicle (UAV) syste...

Ecological pig-raising systems (EPRSs) differ from conventional breeding systems, focusing more on environmental consequences, human health, and food safety during production processes. Thus productions from EPRSs have undergone significant development in China. Thus far, adding plant fiber sources (e.g., sweet potato leaves, maize or wheat straw,...

Unmanned aerial vehicle (UAV)-based multispectral remote sensing effectively monitors agro-ecosystem functioning and predicts crop yield. However, the timing of the remote sensing field campaigns can profoundly impact the accuracy of yield predictions. Little is known on the effects of phenological phases on skills of high-frequency sensing observa...

Unmanned aerial vehicle (UAV) system is an emerging remote sensing tool for profiling crop phenotypic characteristics, as it distinctly captures crop real-time information on field scales. For optimizing UAV agro-monitoring schemes, this study investigated the performance of single-source and multi-source UAV data on maize phenotyping (leaf area in...

Satellite and unmanned aerial vehicle (UAV) remote sensing can be used to estimate soil properties; however, little is known regarding the effects of UAV and satellite remote sensing data integration on the estimation of soil comprehensive attributes, or how to estimate quickly and robustly. In this study, we tackled those gaps by employing UAV mul...

A R T I C L E I N F O Keywords: Urbanization Urban canopy parameter Land cover change Urban boundary layer Surface energy balance A B S T R A C T Changes in land cover and urban canopy structure caused by urbanization have important effects on regional climate. In this study, the Weather Research and Forecasting model is used to explore the influen...

Abundant shallow underground brackish water resources could help in alleviating the shortage of fresh water resources and the crisis concerning agricultural water resources in the North China Plain. Improper brackish water irrigation will increase soil salinity and decrease the final yield due to salt stress affecting the crops. Therefore, it is ur...

The ecological livestock husbandry tends to be popular in China but the real situation is many models appeared without scientific analysis. And very limited theoretical researches compared ecological breeding systems and livestock species on environmental and economic and carrying capacity aspects. To choose the best pig-raising method and compare...

Crop above-ground biomass (AGB) is a key parameter used for monitoring crop growth and predicting yield in precision agriculture. Estimating the crop AGB at a field scale through the use of unmanned aerial vehicles (UAVs) is promising for agronomic application, but the robustness of the methods used for estimation needs to be balanced with practica...

Leaf area index (LAI) is a key biophysical parameter for monitoring crop growth status, predicting crop yield, and quantifying crop variability in agronomic applications. Mapping the LAI at the field scale using multispectral cameras onboard unmanned aerial vehicles (UAVs) is a promising precision-agriculture application with specific requirements:...

UAV hyperspectral remote sensing is a new means of low-cost，high-precision acquisition of finescale crop biophysical parameters and biochemical parameters，so that the rapid inversion of Leaf Area Index (LAI) has a crop growth assessment and yield prediction. Taking the corn of Shandong Yucheng as the research object，using the PROSAIL radiation tran...

The intensification and industrialization of agricultural production leads to more and more serious separation of crop and livestock, which causes serious contradiction between livestock excrement and environment, and major challenges for agricultural sustainable development. Here, we quantitatively investigated the spatial pattern and evolutionary...

Fast and accurate prediction of crop yield at field scale is an effective way to optimize agricultural management by government or local farmers for improving agriculture production. Compared with satellite remote sensing, unmanned aerial vehicle (UAV) remote sensing monitoring system has some advantages, such as obtaining images at high spatial re...