This page has only limited features, please log in for full access.
Nitrogen (N) application and salinity are key factors influencing crop yield and net economic benefit in coastal saline-alkali soils. Integrated analysis and optimization of the benefits of wheat-corn cropping under different nitrogen applications in saline soils could provide lay the scientific basis for sustainable development of agriculture in coastal farmlands. A total of 571 pair-reviewed literature data on two-factor cross-over trials, involving soil salinity and nitrogen application, were integratively analyzed. Based on multi-objective optimization of crop yield, agronomic and net economic benefits, and soil nitrate residue in coastal saline-alkali soils, area-specific nitrogen application strategies were developed. The results showed that increasing the N application rate under 1.8–2.9‰ salinity can increase crop yield and economic benefits. The net economic benefit of crops was negative under 3.5‰ salinity. Above that threshold of 3.5‰, it is not suitable for planting food crops. Consequently, it is necessary to strengthen the management of saline-alkali soils. While the application rate of 2.78 × 108 kg N in winter wheat/summer corn cropping ensured environmental protection, farmers preferred 3.08 × 108 kg of nitrogen dose. These were respectively 40.4% and 33.9% lower than the traditional dose and with relatively higher benefits too.
Hanyou Xie; Jing Li; Yitao Zhang; Xiangbo Xu; Lingqing Wang; Zhu Ouyang. Evaluation of coastal farming under salinization and optimized fertilization strategies in China. Science of The Total Environment 2021, 797, 149038 .
AMA StyleHanyou Xie, Jing Li, Yitao Zhang, Xiangbo Xu, Lingqing Wang, Zhu Ouyang. Evaluation of coastal farming under salinization and optimized fertilization strategies in China. Science of The Total Environment. 2021; 797 ():149038.
Chicago/Turabian StyleHanyou Xie; Jing Li; Yitao Zhang; Xiangbo Xu; Lingqing Wang; Zhu Ouyang. 2021. "Evaluation of coastal farming under salinization and optimized fertilization strategies in China." Science of The Total Environment 797, no. : 149038.
With the rapid development of circular agriculture in China, balancing agricultural income and environmental impact by adjusting the structure and scale of circular agriculture is becoming increasingly important. Agriculture is a major source of greenhouse gas and income earned from agriculture drives sustainable agricultural development. This paper built a multi-objective linear programming model based on greenhouse gas emission and agricultural product income and then optimized the structure and scale of circular agriculture using Beiqiu Farm as a case study. Results showed that greenhouse gas emission was mainly from manure management in livestock industry. While the agriculture income increased by 64% after optimization, GHG emission increased by only 12.3%. The optimization made full use of straw, manure and fodder, but also minimized soil nitrogen loss. The results laid a generalized guide for adjusting the structure and scale of the planting and raising industry. Measures for optimizing the management of manure were critical in achieving low agricultural carbon emissions in future agricultural development efforts.
Sheng Hang; Jing Li; Xiangbo Xu; Yun Lyu; Yang Li; Huarui Gong; Yan Xu; Zhu Ouyang. An Optimization Scheme of Balancing GHG Emission and Income in Circular Agriculture System. Sustainability 2021, 13, 7154 .
AMA StyleSheng Hang, Jing Li, Xiangbo Xu, Yun Lyu, Yang Li, Huarui Gong, Yan Xu, Zhu Ouyang. An Optimization Scheme of Balancing GHG Emission and Income in Circular Agriculture System. Sustainability. 2021; 13 (13):7154.
Chicago/Turabian StyleSheng Hang; Jing Li; Xiangbo Xu; Yun Lyu; Yang Li; Huarui Gong; Yan Xu; Zhu Ouyang. 2021. "An Optimization Scheme of Balancing GHG Emission and Income in Circular Agriculture System." Sustainability 13, no. 13: 7154.
The intensive development of the Yellow River Delta has caused huge transportation of non-point pollutants into the Bohai Sea through source river estuaries and thus poses a considerable threat to eco-environmental security in the region. Long-term irrigation in the Yellow River basin, with occasional heavy rainfall and the related effects of ensuring hydrological processes and human activities in terms of nitrate N transport via surface water systems, is unclear. Using stable isotope (δ2H-H2O and δ18O-H2O, δ15N-NO3− and δ18O-NO3−) and auxiliary geographic data, the ISO source model was run to quantitatively analyze the supply relationship of river systems and the rapid change in the spatial pattern of nitrate N due to heavy rainfall in the estuarine delta. This analysis made clear the dominant contribution of agricultural activities and urbanization to NO3−-N emission, on which basis refined management measures were proposed to deal with NO3− in surface water from the “source-process”. The results of the study show that: (1) The relationship of surface water replenishment in the Yellow River Delta was affected not only by rainfall, irrigation, and other water conservancy measures but also the proportion of water from Yellow River flow declined from the source to estuary; (2) To a certain extent, rainfall diluted the concentration of nitrate N in the river and increased instantaneous flux of nitrate N into the sea, where nitrate N flux continuously increased from upstream to downstream; (3) The rapid deposition of nitrate in the estuary delta was driven by heavy rainfall and human activities such as excessive use of nitrogen fertilizers, rapid urbanization, and livestock waste discharge, and; (4) Scientific measures were needed to realize the interactive effect of the output of non-point source pollutants and the carrying and absorption capacity of coastal fragile ecosystems of the exogenous inputs.
Hanyou Xie; Chong Huang; Jing Li; Yitao Zhang; Xiangbo Xu; Deyao Liu; Zhu Ouyang. Strong Precipitation and Human Activity Spur Rapid Nitrate Deposition in Estuarine Delta: Multi-Isotope and Auxiliary Data Evidence. International Journal of Environmental Research and Public Health 2021, 18, 6221 .
AMA StyleHanyou Xie, Chong Huang, Jing Li, Yitao Zhang, Xiangbo Xu, Deyao Liu, Zhu Ouyang. Strong Precipitation and Human Activity Spur Rapid Nitrate Deposition in Estuarine Delta: Multi-Isotope and Auxiliary Data Evidence. International Journal of Environmental Research and Public Health. 2021; 18 (12):6221.
Chicago/Turabian StyleHanyou Xie; Chong Huang; Jing Li; Yitao Zhang; Xiangbo Xu; Deyao Liu; Zhu Ouyang. 2021. "Strong Precipitation and Human Activity Spur Rapid Nitrate Deposition in Estuarine Delta: Multi-Isotope and Auxiliary Data Evidence." International Journal of Environmental Research and Public Health 18, no. 12: 6221.
Examination of the tradeoff between the extent of decreasing nitrogen input and pest suppression is crucial for maintaining the balance between essential yield and an efficient, sustainable pest control strategy. In this study, an experiment with four manipulated nitrogen fertilizer levels (70, 140, 210, and 280 kg N ha−1 = conventional level) was conducted to explore the effects of decreasing nitrogen on cereal aphids (Sitobion avenae and Rhopalosiphum padi) (Hemiptera: Aphididae), Aphidiinae parasitoids (Hymenoptera: Braconidae: Aphidiinae), and body sizes of parasitoids. The results indicated that nitrogen application, in the range of 70–280 kg N ha−1, has the potential to impact the populations of cereal aphids and their parasitoids. However, both differences between densities of cereal aphids and their parasitoids in moderate (140–210 kg N ha−1) and those in high nitrogen input (280 kg N ha−1) were not significant, and the parasitism rate was also unaffected. A higher parasitism rate reduced population growth of the cereal aphid (S. avenae). Additionally, a moderate decrease of nitrogen fertilizer from 280 to 140–210 kg N ha−1 maximized the body sizes of Aphidiinae parasitoids, indicating that a moderate decrease of nitrogen fertilizer could facilitate biocontrol of cereal aphid by parasitoids in the near future. We conclude that a moderate decrease in nitrogen application, from 280 to 140–210 kg N ha−1, does not quantitatively impact the densities of cereal aphids or the parasitism rate but can qualitatively maximize the fitness of the parasitoids.
Fei Qiao; Quan-Feng Yang; Rui-Xing Hou; Ke-Ning Zhang; Jing Li; Feng Ge; Fang Ouyang. Moderately decreasing fertilizer in fields does not reduce populations of cereal aphids but maximizes fitness of parasitoids. Scientific Reports 2021, 11, 1 -10.
AMA StyleFei Qiao, Quan-Feng Yang, Rui-Xing Hou, Ke-Ning Zhang, Jing Li, Feng Ge, Fang Ouyang. Moderately decreasing fertilizer in fields does not reduce populations of cereal aphids but maximizes fitness of parasitoids. Scientific Reports. 2021; 11 (1):1-10.
Chicago/Turabian StyleFei Qiao; Quan-Feng Yang; Rui-Xing Hou; Ke-Ning Zhang; Jing Li; Feng Ge; Fang Ouyang. 2021. "Moderately decreasing fertilizer in fields does not reduce populations of cereal aphids but maximizes fitness of parasitoids." Scientific Reports 11, no. 1: 1-10.
The high concentration of heavy metal in livestock manures is an increasing concern because it has the potential to pollute farmlands. Excessive mineral additives in feeds are the source of heavy metals in the manures. Recently, China has issued new regulations to restrict the use of high-dose mineral feeds. To reduce pollution and to increase the benefits to the industry, it is critical to understand the characteristics of heavy metals in feeds and to develop alternatives that are more efficient. This study analyzed 175 articles (1751 valid data) published in 2000–2020 in peer-reviewed journals. The analysis covered the characteristics of minerals in pig feeds in China, summarized the effects of different additives and discussed the relationships with feed standards. It was noted that Cu and Zn exceeded existing standards for pig feeds. Organic and new inorganic mineral supplements can effectively replace high-dose inorganic minerals to reduce incidents of diarrhea in piglets, improve growth performance and reduce pollution. With the recommended replacement, Zn and Cu in pig manure can be reduced respectively by 8.21×107and 3.23×107 kg per year. It can also improve product quality and efficiency and increase income of breeding enterprises by USD 1.28×1010per year.
Yan Xu; Jing Li; Zhu Ouyang; Hao Zhang. Implications of feed mineral reduction and enhancement for China's feed standards. Resources, Conservation and Recycling 2020, 168, 105342 .
AMA StyleYan Xu, Jing Li, Zhu Ouyang, Hao Zhang. Implications of feed mineral reduction and enhancement for China's feed standards. Resources, Conservation and Recycling. 2020; 168 ():105342.
Chicago/Turabian StyleYan Xu; Jing Li; Zhu Ouyang; Hao Zhang. 2020. "Implications of feed mineral reduction and enhancement for China's feed standards." Resources, Conservation and Recycling 168, no. : 105342.
Optimization of fertilizer and tillage management in agroecosystems can be an effective strategy to reduce greenhouse gas (GHG) emission and improve carbon sequestration. Using a system boundary that started at winter wheat seeding and ended at summer maize harvest, a field experiment was conducted in Shandong Province (North China) to determine the effect of microbial fertilization and tillage on the carbon footprint (CF). The climate-based ecosystem services were evaluated in wheat-maize cropping systems. Also the optimal microbial fertilization and tillage with the lowest CF, highest climate-based ecosystem services and highest crop yield were determined. The results showed that compared with microbial organic fertilization, the use of microbial decomposing agents increased soil organic carbon (SOC) sequestration (2582.1–2909.9 kg CO2-eq ha−1 yr−1) and reduced CF (0.11–0.12 kg CO2-eq kg−1 grain). Chemical fertilization was the largest contributor to total CF (27.5–56.7%), which decreased with decreasing chemical fertilization. Climate-based ecosystem services of microbial fertilization with rotary tillage (1689.9–1795.6 US$ ha−1 yr−1) were significantly higher than those of chemical fertilization. In the limited system boundary of wheat-maize cropping, microbial decomposing agent MA (of 30 L ha−1) with rotary tillage had the highest grain production, GHG emission mitigation and climate-based ecosystem services enhancement.
Huarui Gong; Jing Li; Mingxing Sun; Xiangbo Xu; Zhu Ouyang. Lowering carbon footprint of wheat-maize cropping system in North China Plain: Through microbial fertilizer application with adaptive tillage. Journal of Cleaner Production 2020, 268, 122255 .
AMA StyleHuarui Gong, Jing Li, Mingxing Sun, Xiangbo Xu, Zhu Ouyang. Lowering carbon footprint of wheat-maize cropping system in North China Plain: Through microbial fertilizer application with adaptive tillage. Journal of Cleaner Production. 2020; 268 ():122255.
Chicago/Turabian StyleHuarui Gong; Jing Li; Mingxing Sun; Xiangbo Xu; Zhu Ouyang. 2020. "Lowering carbon footprint of wheat-maize cropping system in North China Plain: Through microbial fertilizer application with adaptive tillage." Journal of Cleaner Production 268, no. : 122255.
The expansion of rubber (Hevea brasiliensis) plantations has been a critical driver for the rapid transformation of tropical forests, especially in Thailand. Rubber plantation mapping provides basic information for surveying resources, updating forest subplot information, logging, and managing the forest. However, due to the diversity of stand structure, complexity of the forest growth environment, and the similarity of spectral characteristics between rubber trees and natural forests, it is difficult to discriminate rubber plantation from natural forest using only spectral information. This study evaluated the validity of textural features for rubber plantation recognition at different spatial resolutions using GaoFen-1 (GF-1), Sentinel-2, and Landsat 8 optical data. C-band Sentinel-1 10 m imagery was first used to map forests (including both rubber plantations and natural forests) and non-forests, then the pixels identified as forests in the Sentinel-1 imagery were compared with GF-1, Sentinel-2, and Landsat 8 images to separate rubber plantations and natural forest using two different approaches: a method based on spectral information characteristics only and a method combining spectral and textural features. In addition, we extracted textural features of different window sizes (3 × 3 to 31 × 31) and analyzed the influence of window size on the separability of rubber plantations and natural forests. Our major findings include: (1) the suitable texture extraction window sizes of GF-1, Sentinel-2, and Landsat 8 are 31 × 31, 11 × 11 to 15 × 15, and 3 × 3 to 7 × 7, respectively; (2) correlation (COR) is a robust textural feature in remote sensing images with different resolutions; and (3) compared with classification by spectral information only, the producer’s accuracy of rubber plantations based on GF-1, Sentinel-2, and Landsat 8 was improved by 8.04%, 9.44%, and 8.74%, respectively, and the user’s accuracy was increased by 4.63%, 4.54%, and 6.75%, respectively, when the textural features were introduced. These results demonstrate that the method combining textural features has great potential in delineating rubber plantations.
Chenchen Zhang; Chong Huang; He Li; Qingsheng Liu; Jing Li; Arika Bridhikitti; Gaohuan Liu. Effect of Textural Features in Remote Sensed Data on Rubber Plantation Extraction at Different Levels of Spatial Resolution. Forests 2020, 11, 399 .
AMA StyleChenchen Zhang, Chong Huang, He Li, Qingsheng Liu, Jing Li, Arika Bridhikitti, Gaohuan Liu. Effect of Textural Features in Remote Sensed Data on Rubber Plantation Extraction at Different Levels of Spatial Resolution. Forests. 2020; 11 (4):399.
Chicago/Turabian StyleChenchen Zhang; Chong Huang; He Li; Qingsheng Liu; Jing Li; Arika Bridhikitti; Gaohuan Liu. 2020. "Effect of Textural Features in Remote Sensed Data on Rubber Plantation Extraction at Different Levels of Spatial Resolution." Forests 11, no. 4: 399.
Grapes are the most important cash crop in Xinjiang. However, the effective utilization of agricultural water and fertilizer in this area is relatively low, which is very unfavourable for the development of Xinjiang grape industry. At present, there is a lack of research based on multi-objective water and fertilizer optimization to guide grape production. Field experiments were thus conducted over three consecutive years (2015–2017) to study the effects of water and fertilizer coupling on the yield, fruit quality, water use efficiency (WUE), fertilizer partial productivity (PFP), and net profits of Vitis vinifera cv. “Frey” grapes in northern Xinjiang. The optimum input range of water and fertilizer for multi-objective optimization were determined by using multiple regression and spatial analysis. Five levels of N–P2O5–K2O (180–225–495, 240–300–660, 300–375–825, 360–450–990, 420–525–1155 kg ha−1) were set up in the experiment, designated F60 %, F80 %, F100 %, F120 %, and F140 %, respectively. Three drip irrigation levels were designated W60 %, W80 %, W100 %, accounting for 60 %, 80 %, and 100 % of the ETc (where ETc denotes evapotranspiration under sufficient water supply for crops). The results show that at the same fertilization level, the leaf area index (LAI), vitamin C content, titratable acid, soluble solids content, dry matter yield, grape yield, PFP, and net profit increased with an increase in irrigation. They reached their maximum under full irrigation (W100 %). Compared to W80 % and W60 % irrigation levels, the WUE at a full (W100 %) irrigation was lower, but the PFP was the highest. The maximum grape bunch weight over three years was 407, 383, and 378 g, respectively. The highest harvest index (HI) was 0.460, 0.425, and 0.416, respectively. When the irrigation range was 334–348 mm and the N–P2O5–K2O fertilization range was 320–400–880∼392–490–1077 kg ha−1, the grape yield, net profit, WUE, vitamin C content, titratable acid content, and soluble solids content of the fruits reached more than 90 % of their maximum values simultaneously. The results of this research provide a scientific reference for water and fertilizer management of drip irrigation in Xinjiang vineyards.
Xinxin Li; Hongguang Liu; Jing Li; Xinlin He; Ping Gong; En Lin; Kaiming Li; Ling Li; Andrew Binley. Experimental study and multi–objective optimization for drip irrigation of grapes in arid areas of northwest China. Agricultural Water Management 2020, 232, 106039 .
AMA StyleXinxin Li, Hongguang Liu, Jing Li, Xinlin He, Ping Gong, En Lin, Kaiming Li, Ling Li, Andrew Binley. Experimental study and multi–objective optimization for drip irrigation of grapes in arid areas of northwest China. Agricultural Water Management. 2020; 232 ():106039.
Chicago/Turabian StyleXinxin Li; Hongguang Liu; Jing Li; Xinlin He; Ping Gong; En Lin; Kaiming Li; Ling Li; Andrew Binley. 2020. "Experimental study and multi–objective optimization for drip irrigation of grapes in arid areas of northwest China." Agricultural Water Management 232, no. : 106039.
The application of bioorganic fertilizer affects rhizosphere microbes and further improves soil fertility in farmlands. However, the effects of different fertilizers on rhizosphere bacterial community diversity and structure of winter wheat remains unclear. In this study, we explored the effects of different fertilization treatments (no fertilizer added, CK; nitrogen fertilizer, NF; bioorganic fertilizer, BOF) on the rhizosphere bacterial community of winter wheat in the North China Plain. Rhizosphere soil treated with BOF had a higher Shannon index than that of CK and NF. The relative abundance of the Proteobacteria treated with BOF was significantly higher than that of NF, while the Acidobacteria and Planctomycetes were significantly lower. The redundancy analysis (RDA) and Mantel test showed that soil bacterial communities were significantly correlated with pH, nitrate, available phosphorus (AP), and available potassium (AK). Our findings indicated that BOF increased bacterial diversity and the relative abundance of copiotrophic bacteria in rhizosphere soil, while NF reduced bacterial diversity and increased the relative abundance of oligotrophic bacteria. The increase in copiotrophic bacteria in the rhizosphere of winter wheat could indicate an increase in soil nutrient availability, which might have positive implications for soil fertility and crop production.
Rubiao Liang; Ruixing Hou; Jing Li; Yun Lyu; Sheng Hang; Huarui Gong; Zhu Ouyang. Effects of Different Fertilizers on Rhizosphere Bacterial Communities of Winter Wheat in the North China Plain. Agronomy 2020, 10, 93 .
AMA StyleRubiao Liang, Ruixing Hou, Jing Li, Yun Lyu, Sheng Hang, Huarui Gong, Zhu Ouyang. Effects of Different Fertilizers on Rhizosphere Bacterial Communities of Winter Wheat in the North China Plain. Agronomy. 2020; 10 (1):93.
Chicago/Turabian StyleRubiao Liang; Ruixing Hou; Jing Li; Yun Lyu; Sheng Hang; Huarui Gong; Zhu Ouyang. 2020. "Effects of Different Fertilizers on Rhizosphere Bacterial Communities of Winter Wheat in the North China Plain." Agronomy 10, no. 1: 93.
Ammonia (NH3) is one of the main polluted gases in the atmosphere, and its emission has markedly increased in recent years. In China, NH3 is mainly emitted from agricultural fields. Using city-wide data on NH3 emissions in agricultural fields, the spatio-temporal emission of NH3 was estimated for North China. This included emissions from nitrogen fertilizers, field straws, background soil, nitrogen-fixing plants, human feces, and livestock/poultry manure. Based on the results, the range of NH3 emission in agricultural lands was 1623.0-1801.5 Gg/year. The rate of increase in NH3 emission in the period 2003-2015 was 0.74% per year, which was relatively stable. The leading sources of NH3 emission included the excessive use of chemical fertilizers in agriculture and the continuous expansion of livestock and poultry industries scale, accounting respectively for 44.9% and 43.9% NH3 emission in the study area, respectively. Hebei and Shandong provinces contributed the highest NH3 emission in North China. The contribution rate of NH3 emission in each province varied with sources, agricultural development, and population density. Based on the 1 km × 1 km grid resolution map for NH3 emission, the range and average of emission were 9.72-10.13 kg/ha and 9.95 kg/ha, respectively. High emissions were in the southeast of Hebei province and most of Shandong province. For these regions, there is a need for changes in policies relating to the use of chemical fertilizers in agriculture and the management methods of livestock production in the region.
Weibin Zeng; Jing Li. Spatio-temporal distribution of ammonia (NH3) emissions in agricultural fields across North China. Environmental Science and Pollution Research 2020, 27, 8129 -8141.
AMA StyleWeibin Zeng, Jing Li. Spatio-temporal distribution of ammonia (NH3) emissions in agricultural fields across North China. Environmental Science and Pollution Research. 2020; 27 (8):8129-8141.
Chicago/Turabian StyleWeibin Zeng; Jing Li. 2020. "Spatio-temporal distribution of ammonia (NH3) emissions in agricultural fields across North China." Environmental Science and Pollution Research 27, no. 8: 8129-8141.
The structure of the pig-raising sector in China is changing towards large-scale and intensive systems or ecological pig-raising systems (EPRSs). To choose the best EPRS with high economic benefits and with low environmental consequences, this study combined economic analysis and emergy analysis methods to evaluate several EPRSs. Having a large percentage of maize silage in the feed (max 40%) to replace some maize increased the economic benefit and sustainability of the EPRS and decreased the pressure on the environment. The raising system that consisted of Tuhe black pigs fed feed containing maize silage (EPRS C) performed especially well. The yield-based economic profit and area-based economic profit of EPRS C increased by 37%–54% and 3%–17%, respectively, compared to those of the three-breed crossbred pig-raising systems with or without maize silage added to the feed (EPRS A and EPRS B). Its unit emergy value and emergy loading ratio were 9–22% and 10–15% lower, respectively, than those of EPRS A and EPRS B. Furthermore, its emergy yield ratio and emergy sustainability index were about 2% and 14%–19% higher, respectively, than those of EPRS A and EPRS B. To some extent, the results from EPRS C give some guidelines on improving the performance of the ecological pig-raising sector in China. Moreover, using a high concentration of maize silage in the feed and an optimal local pig type may be beneficial for the sustainability of the ecological pig-raising sector in China.
Lyu Yun; Jing Li; Ruixing Hou; Zhigang Sun; Peifei Cong; Rubiao Liang; Sheng Hang; Huarui Gong; Zhu Ouyang. Emergy-Based Sustainability Analysis of an Ecologically Integrated Model with Maize Planting for Silage and Pig-Raising in the North China Plain. Sustainability 2019, 11, 6485 .
AMA StyleLyu Yun, Jing Li, Ruixing Hou, Zhigang Sun, Peifei Cong, Rubiao Liang, Sheng Hang, Huarui Gong, Zhu Ouyang. Emergy-Based Sustainability Analysis of an Ecologically Integrated Model with Maize Planting for Silage and Pig-Raising in the North China Plain. Sustainability. 2019; 11 (22):6485.
Chicago/Turabian StyleLyu Yun; Jing Li; Ruixing Hou; Zhigang Sun; Peifei Cong; Rubiao Liang; Sheng Hang; Huarui Gong; Zhu Ouyang. 2019. "Emergy-Based Sustainability Analysis of an Ecologically Integrated Model with Maize Planting for Silage and Pig-Raising in the North China Plain." Sustainability 11, no. 22: 6485.
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 practical application. In this study, three UAV remote sensing flight missions (using a multiSPEC-4C multispectral camera, a Micasense RedEdge-M multispectral camera, and an Alpha Series AL3-32 Light Detection and Ranging (LiDAR) sensor onboard three different UAV platforms) were conducted above three long-term experimental plots with different tillage treatments in 2018. We investigated the performances of the multi-source UAV-based 3D point clouds at multi-spatial scales using the traditional multi-variable linear regression model (OLS), random forest (RF), backpropagation neural network (BP), and support vector machine (SVM) methods for accurate AGB estimation. Results showed that crop height (CH) was a robust proxy for AGB estimation, and that high spatial resolution in CH datasets helps to improve maize AGB estimation. Furthermore, the OLS, RF, BP, and SVM methods all maintained an acceptable accuracy for AGB estimation; however, the SVM and RF methods performed slightly more robustly. This study is expected to optimize UAV systems and algorithms for specific agronomic applications.
Wanxue Zhu; Zhigang Sun; Jinbang Peng; Yaohuan Huang; Jing Li; Junqiang Zhang; Bin Yang; Xiaohan Liao. Estimating Maize Above-Ground Biomass Using 3D Point Clouds of Multi-Source Unmanned Aerial Vehicle Data at Multi-Spatial Scales. Remote Sensing 2019, 11, 2678 .
AMA StyleWanxue Zhu, Zhigang Sun, Jinbang Peng, Yaohuan Huang, Jing Li, Junqiang Zhang, Bin Yang, Xiaohan Liao. Estimating Maize Above-Ground Biomass Using 3D Point Clouds of Multi-Source Unmanned Aerial Vehicle Data at Multi-Spatial Scales. Remote Sensing. 2019; 11 (22):2678.
Chicago/Turabian StyleWanxue Zhu; Zhigang Sun; Jinbang Peng; Yaohuan Huang; Jing Li; Junqiang Zhang; Bin Yang; Xiaohan Liao. 2019. "Estimating Maize Above-Ground Biomass Using 3D Point Clouds of Multi-Source Unmanned Aerial Vehicle Data at Multi-Spatial Scales." Remote Sensing 11, no. 22: 2678.
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: The LAI retrieval method should be (1) robust so that crop LAI can be estimated with similar accuracy and (2) easy to use so that it can be applied to the adjustment of field management practices. In this study, three UAV remote-sensing missions (UAVs with Micasense RedEdge-M and Cubert S185 cameras) were carried out over six experimental plots from 2018 to 2019 to investigate the performance of reflectance-based lookup tables (LUTs) and vegetation index (VI)-based LUTs generated from the PROSAIL model for wheat LAI retrieval. The effects of the central wavelengths and bandwidths for the VI calculations on the LAI retrieval were further examined. We found that the VI-LUT strategy was more robust and accurate than the reflectance-LUT strategy. The differences in the LAI retrieval accuracy among the four VI-LUTs were small, although the improved modified chlorophyll absorption ratio index-lookup table (MCARI2-LUT) and normalized difference vegetation index-lookup table (NDVI-LUT) performed slightly better. We also found that both of the central wavelengths and bandwidths of the VIs had effects on the LAI retrieval. The VI-LUTs with optimized central wavelengths (red = 612 nm, near-infrared (NIR) = 756 nm) and narrow bandwidths (~4 nm) improved the wheat LAI retrieval accuracy (R2 ≥ 0.75). The results of this study provide an alternative method for retrieving crop LAI, which is robust and easy use for precision-agriculture applications and may be helpful for designing UAV multispectral cameras for agricultural monitoring.
Wanxue Zhu; Zhigang Sun; Yaohuan Huang; Jianbin Lai; Jing Li; Junqiang Zhang; Bin Yang; Binbin Li; Shiji Li; Kangying Zhu; Yang Li; Xiaohan Liao. Improving Field-Scale Wheat LAI Retrieval Based on UAV Remote-Sensing Observations and Optimized VI-LUTs. Remote Sensing 2019, 11, 2456 .
AMA StyleWanxue Zhu, Zhigang Sun, Yaohuan Huang, Jianbin Lai, Jing Li, Junqiang Zhang, Bin Yang, Binbin Li, Shiji Li, Kangying Zhu, Yang Li, Xiaohan Liao. Improving Field-Scale Wheat LAI Retrieval Based on UAV Remote-Sensing Observations and Optimized VI-LUTs. Remote Sensing. 2019; 11 (20):2456.
Chicago/Turabian StyleWanxue Zhu; Zhigang Sun; Yaohuan Huang; Jianbin Lai; Jing Li; Junqiang Zhang; Bin Yang; Binbin Li; Shiji Li; Kangying Zhu; Yang Li; Xiaohan Liao. 2019. "Improving Field-Scale Wheat LAI Retrieval Based on UAV Remote-Sensing Observations and Optimized VI-LUTs." Remote Sensing 11, no. 20: 2456.
Manure generated from livestock farming is currently the focus of attention of global scientific community. China's livestock manure is extremely rich with a high potential for heavy metal contamination. Here, data were collected for 2000–2018.6 from China's National Statistical Data, Elsevier, China National Knowledge Infrastructure and other literature databases and analyzed for "feed–feces–soil" chain of heavy metals. An integrated analysis was done to explore the reductive effect of existing technologies on heavy metals in cattle manure. Excessive addition of heavy metal elements to feed is widespread in China. High amounts of undigested heavy metals are excreted through animal manure. The study showed that spatial variability of heavy metal contents in cattle manure was extremely large. The excess cupper (Cu) was higher than that of zinc (Zn), and was higher in southern than in northern China. Chemical treatments were more effective than physical and biological ones in controlling heavy metal pollution. The optimal reduction ratios of the effective Zn and Cu contents were 21.72% and 33.11%, respectively. The Zn and Cu contents could be reduced by 1.96 × 107 and 5.92 × 106 kg per year, respectively. This could reduce the risks posed by heavy metals after manure-based fertilizer applications in crop cultivation.
Yan Xu; Jing Li; Xubo Zhang; Lingqing Wang; Xiangbo Xu; Li Xu; Huarui Gong; Hanyou Xie; Fadong Li. Data integration analysis: Heavy metal pollution in China's large-scale cattle rearing and reduction potential in manure utilization. Journal of Cleaner Production 2019, 232, 308 -317.
AMA StyleYan Xu, Jing Li, Xubo Zhang, Lingqing Wang, Xiangbo Xu, Li Xu, Huarui Gong, Hanyou Xie, Fadong Li. Data integration analysis: Heavy metal pollution in China's large-scale cattle rearing and reduction potential in manure utilization. Journal of Cleaner Production. 2019; 232 ():308-317.
Chicago/Turabian StyleYan Xu; Jing Li; Xubo Zhang; Lingqing Wang; Xiangbo Xu; Li Xu; Huarui Gong; Hanyou Xie; Fadong Li. 2019. "Data integration analysis: Heavy metal pollution in China's large-scale cattle rearing and reduction potential in manure utilization." Journal of Cleaner Production 232, no. : 308-317.
Vegetable greenhouses form a significant land utilisation pattern in China. A case study of the greenhouse soil quality changes and potential risk to humans under a specific long-term environment, which includes high fertilization rates, high temperatures and humidity levels and out-of-season cultivation, is presented in this study. Soil profiles of 72 representative solar greenhouses with various planting years were sampled in Shouguang City, which is the birthplace of winter greenhouse in China. The temporal distribution of soil quality changes were quantitatively evaluated through the application of a correlation analysis and soil quality assessment. The soil was highly enriched with phosphorus and potassium and had low organic matter content. The organic matter, nitrogen, phosphorus and potassium contents increased with the years planted, reached their peak values after 5-10 a, and declined as the soil layer’s depth increased. The infiltration rate of nitrate was relatively high, which poses risks to underground water safety. A comprehensive soil quality assessment revealed that in vegetable greenhouses planted for different periods, the soil quality improved at first and then sharply declined after 10 a. Studying greenhouse soil quality changes will aid in implementing nutrient management strategies to improve the soil quality and sustainable development programs for the vegetable industry. Keywords: vegetable greenhouse, facility agriculture, planting years, soil quality, microbial activity DOI: 10.25165/j.ijabe.20191201.4092 Citation: Li J, Xu Y, Liu H G. Variations of soil quality from continuously planting greenhouses in North China. Int J Agric & Biol Eng, 2019; 12(1): 139–145.
Jing Li; Yan Xu; Hongguang Liu. Variations of soil quality from continuously planting greenhouses in North China. International Journal of Agricultural and Biological Engineering 2019, 12, 139 -145.
AMA StyleJing Li, Yan Xu, Hongguang Liu. Variations of soil quality from continuously planting greenhouses in North China. International Journal of Agricultural and Biological Engineering. 2019; 12 (1):139-145.
Chicago/Turabian StyleJing Li; Yan Xu; Hongguang Liu. 2019. "Variations of soil quality from continuously planting greenhouses in North China." International Journal of Agricultural and Biological Engineering 12, no. 1: 139-145.
Mining activities make important contributions to economic growth, but they can also produce massive amounts of solid waste, such as tailings and metal accumulations. Taking the Urad Houqi mining area in Inner Mongolia as the study area, this study systematically assessed the contamination risk of arsenic and heavy metals in the soils of the study area and explored the contamination characteristics in a key polymetallic mining area. For the whole study area, based on the Nemerow comprehensive pollution method, almost half of the investigated sites were contaminated, and the most contaminated site was Urad Houqi Qianzhen Mineral Concentration Co., Ltd. (Bayannaoer, China), a cooperation between the lead and zinc mining industry. The assessment results indicated that Cd and As were the elements of greatest concern, followed by Pb, Cr and Hg. Particularly, for the typical Dongshengmiao mining area, when compared with the GB15618-1995 standard values, As, Zn and Cd posed the most serious contamination threat, while Cr and Ni exhibited clean conditions. In addition, the vertical distribution maps demonstrated that the contents of arsenic and metals in some soil profiles were correlated with sampling depth. Therefore, arsenic and heavy metals pose high threat to soil ecosystems in this area, there is encouragement for some control and remediation measures to be taken into effect.
Shuai Song; Yuanjie Li; Lin Li; Maoyong Liu; Jing Li; Liang Wang; Chao Su. Arsenic and Heavy Metal Accumulation and Risk Assessment in Soils around Mining Areas: The Urad Houqi Area in Arid Northwest China as an Example. International Journal of Environmental Research and Public Health 2018, 15, 2410 .
AMA StyleShuai Song, Yuanjie Li, Lin Li, Maoyong Liu, Jing Li, Liang Wang, Chao Su. Arsenic and Heavy Metal Accumulation and Risk Assessment in Soils around Mining Areas: The Urad Houqi Area in Arid Northwest China as an Example. International Journal of Environmental Research and Public Health. 2018; 15 (11):2410.
Chicago/Turabian StyleShuai Song; Yuanjie Li; Lin Li; Maoyong Liu; Jing Li; Liang Wang; Chao Su. 2018. "Arsenic and Heavy Metal Accumulation and Risk Assessment in Soils around Mining Areas: The Urad Houqi Area in Arid Northwest China as an Example." International Journal of Environmental Research and Public Health 15, no. 11: 2410.
Using microbial agents combined with chemical fertilizers is a promising approach to maintain the soil microbiota balance in continuous wheat–crop rotation fields. Most previous studies focused on microbial agents applied in the topsoil, with limited studies investigating the effects microbial agents under different tillage practices on soil quality and crops growth. In this study, a field experiment was conducted using a two-factor randomized block design (tillage practices and fertilizer applications) with three replicates, the effects of conventional rotary tillage and deep plowing when applying two different types of microbial agents (ETS and JS) on the dry matter accumulation, yield, soil microbial index and soil respiration of winter wheat (Triticum aestivum L.) in north China. The results indicated that wheat grain yield was not decreased after the application of different microbial agents plus 70% of the normal amount of chemical fertilizer and that the straw yield was decreased by 19.1% and 16.4% when ETS and JS, respectively, were individually applied. Additionally, there were no differences in grain and straw yields between the different tillage practices. The aboveground dry matter accumulation increased by 47.5% with ETS application under conventional rotary tillage compared with applications of chemical fertilizer. Under conventional rotary tillage, applications of different microbial agents decreased the microbial biomass C (MBC) concentration by 35.2–42.3% compared with applications of chemical fertilizer, while, the microbial biomass N (MBN) concentration increased by 10.0–18.5% in the 0–20-cm soil layer. With deep plowing, the soil respiration rate was greater than under conventional rotary tillage. In addition, the soil respiration rate after the application of the ETS plus JS combination with deep plowing was greater than after the microbial agents were individually applied during wheat’s growth period.
Huarui Gong; Jing Li; Junhua Ma; Fadong Li; Zhu Ouyang; Congke Gu. Effects of tillage practices and microbial agent applications on dry matter accumulation, yield and the soil microbial index of winter wheat in North China. Soil and Tillage Research 2018, 184, 235 -242.
AMA StyleHuarui Gong, Jing Li, Junhua Ma, Fadong Li, Zhu Ouyang, Congke Gu. Effects of tillage practices and microbial agent applications on dry matter accumulation, yield and the soil microbial index of winter wheat in North China. Soil and Tillage Research. 2018; 184 ():235-242.
Chicago/Turabian StyleHuarui Gong; Jing Li; Junhua Ma; Fadong Li; Zhu Ouyang; Congke Gu. 2018. "Effects of tillage practices and microbial agent applications on dry matter accumulation, yield and the soil microbial index of winter wheat in North China." Soil and Tillage Research 184, no. : 235-242.
Environmental processes and biological community structures change along fluvial gradients within coastal river basins; the accumulation and associated risk of metal contamination would also be expected to change from upstream to downstream reaches. Speciation and degrees of contamination of metals in sediments from the upstream and downstream of river catchments of the southern Bohai Sea were investigated. The mean concentrations of Cu, Zn, Cr, Ni, Cd and Pb from upstream reaches were 82.6, 157, 63.6, 26.6, 0.18 and 24.9 mg/kg, respectively. The mean concentrations of Cu, Zn, Cr, Ni, Cd and Pb from downstream reaches were 38.0, 66.0, 38.9, 18.1, 0.16 and 24.0 mg/kg, respectively. Most of the Cu, Zn, Cr, Ni and Pb in sediments from both the upstream and downstream reaches was mainly associated with the residual fraction. However, Cd was preferentially bound to the exchangeable phase. A cluster analysis was used to study the degree of association between sites, and three distinct clusters were identified in both upstream and downstream sediments. A correlation analysis was conducted to determine the extent of association among metals and showed that metals in sediments from the upstream reaches have more affinity than those in the downstream area. Sediment quality guidelines were used to evaluate potential risks. The risks from Zn, Cr and Ni in the upstream reaches were higher than those from downstream reaches; however, the other three metals (Cu, Pb and Cd) showed opposite results.
Li Xu; Jing Li. Speciation and Degrees of Contamination of Metals in Sediments from Upstream and Downstream Reaches along the Catchment of the Southern Bohai Sea, China. International Journal of Environmental Research and Public Health 2015, 12, 7959 -7973.
AMA StyleLi Xu, Jing Li. Speciation and Degrees of Contamination of Metals in Sediments from Upstream and Downstream Reaches along the Catchment of the Southern Bohai Sea, China. International Journal of Environmental Research and Public Health. 2015; 12 (7):7959-7973.
Chicago/Turabian StyleLi Xu; Jing Li. 2015. "Speciation and Degrees of Contamination of Metals in Sediments from Upstream and Downstream Reaches along the Catchment of the Southern Bohai Sea, China." International Journal of Environmental Research and Public Health 12, no. 7: 7959-7973.
The magnitude and ecological relevance of metal pollution from the upstream of water sources after emergency pollution events was investigated by applying a set of complementary sediment quality assessment methods: (1) geochemical assessment based on background value (the geoaccumulation index); (2) comparisons with sediment quality guidelines (SQGs); (3) an evaluation of the combined pollution according to the risk index (RI); and (4) investigation of the chemical patterns of target heavy metals (Cd, Zn, Cr, Pb, Ni). The geoaccumulation indices (Igeo) suggested that the magnitude of heavy metal pollution of the sediment of Yanghe River decreased in the order of Cd > Zn > Pb > Cr > Ni. Risk analysis also suggested that Cd and Zn concentrations were sufficiently elevated as to cause adverse biological effects in this study area. According to the RI values, 27% of total sampling sites showed considerable ecological risk for the water body, and 53% of total sampling sites showed very high ecological risk for the waterbody. Sediment-bound Cd was found to be predominantly associated with the exchangeable phase of the sediment (25%–68%), while Cr, Ni, Zn and Pb showed the strongest association with the residual fractions (60%–92%, 53%–67%, 24%–85% and 35%–67%, respectively).
Jing Li. Risk Assessment of Heavy Metals in Surface Sediments from the Yanghe River, China. International Journal of Environmental Research and Public Health 2014, 11, 12441 -12453.
AMA StyleJing Li. Risk Assessment of Heavy Metals in Surface Sediments from the Yanghe River, China. International Journal of Environmental Research and Public Health. 2014; 11 (12):12441-12453.
Chicago/Turabian StyleJing Li. 2014. "Risk Assessment of Heavy Metals in Surface Sediments from the Yanghe River, China." International Journal of Environmental Research and Public Health 11, no. 12: 12441-12453.