Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objective...Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.展开更多
Apple occupies a dominant position in fruit production globally, and has become the main income source of local smallholder farmers in Luochuan County in the Loess Plateau area, one of the largest apple production are...Apple occupies a dominant position in fruit production globally, and has become the main income source of local smallholder farmers in Luochuan County in the Loess Plateau area, one of the largest apple production areas in China. However, the annual productivity of apple orchards in this region remains low and has gradually declined over the years. The distinction and correlation of production constraints can contribute to the promotion of apple orchard productivity and the development of a sustainable orchard system. In the present study, survey data from 71 smallholder farmers were analyzed using a yield gap model to distinguish the production constraints and determine their correlation with the yield gap based on the structural equation model(SEM). The results indicated that the average apple yield in Luochuan County was 29.9 t ha^–1 yr^–1, while the attainable yield(Yatt;the highest yield obtained from the on-farm surveys) was 58.1 t ha^–1 yr^–1. The average explained and unexplainable yield gaps were 26.3 and 1.87 t ha^–1 yr^–1. According to the boundary line analysis, crop load,number of sprayings and base fertilizer N were the top three constraints on apple production in 9.8, 7.8 and 7.8% of the plots, respectively. Among the production constraints, crop load and fruit weight affected apple yield through direct pathways,whereas other constraints influenced apple yield through an indirect pathway based on the SEM, explaining 51% of the yield variance by all the main production constraints. These results can improve the current understanding of production constraints and contribute to the development of management strategies and policies for improving apple yield.展开更多
Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have...Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have scarcely achieved the status of international recognition in commodity markets and research arena outside Africa. This paper presented a critical review of the status of IFT in the Tropical African sub-regions (of West Africa, Central Africa, East Africa, Southern Africa and the Indian Ocean Islands) in relation to the introduced naturalised fruit trees from tropical America and Asia, threats to the diversity and sustainable use of IFT, analysis of the opportunities and challenges of developing IFT, as well as targets for crop improvement of the rich IFT of Tropical Africa. Domestication programme via relevant vegetative propagation techniques for priority IFT of the sub-regions was examined and advocated, in addition to the adoption of complementary conservation strategies, including Field GeneBanks in the management of the continent’s IFT diversity.展开更多
Biochar produced from pyrolysis of biomass such as wood,canopy,animal manure,and agricultural waste is recognized for its stability and for being a benefactor of soil health and plant growth.Its application in forestr...Biochar produced from pyrolysis of biomass such as wood,canopy,animal manure,and agricultural waste is recognized for its stability and for being a benefactor of soil health and plant growth.Its application in forestry is an area with growing research interest due to its ability to enhance soil physicochemical properties,including structure,water retention,and nutrient availability,thereby boosting plant growth,drought tolerance,and resistance to pests and diseases.However,the effectiveness of biochar varies based on factors like biochar type,application rate,soil type,and tree species.Potential risks associated with biochar use include nutrient immobilization,increased pH in alkaline soils,and enhanced leaching of toxic elements.Despite its promise,challenges such as knowledge gaps,lack of sitespecific studies,and concerns of economic viability hinder widespread adoption of biochar in forestry.This qualitative review compiles over 150 published works from the past two decades on biochar application in forestry.It assesses the impacts of biochar on soil health and tree crops,highlighting its potential to improve soil fertility and promote tree growth.The review identifies significant findings,such as the positive influence of biochar on soil and plant health and outlines existing knowledge gaps that need addressing.By synthesizing current research,the review proposes future directions to optimize biochar use in sustainable forestry management,emphasizing the need for tailored approaches and economic assessments to facilitate broader adoption.The findings underscore the potential role of biochar in enhancing forestry practices while calling for further studies to resolve uncertainties and improve its practical implementation.展开更多
苹果作为全球重要的经济作物之一,其产量和质量直接受到病害的影响。为解决目前传统人工检测病害过程中主观性强、效率低,以及农业检测设备资源有限等问题,基于YOLOv8(You Only Look Once Version 8)提出了一种高效、轻量化的病害检测...苹果作为全球重要的经济作物之一,其产量和质量直接受到病害的影响。为解决目前传统人工检测病害过程中主观性强、效率低,以及农业检测设备资源有限等问题,基于YOLOv8(You Only Look Once Version 8)提出了一种高效、轻量化的病害检测模型—YOLOv8-RIC。在YOLOv8的基础上对主干网络进行了优化,分别引入了轻量级卷积神经网络RGN(RepGhostNet)和改进型残差移动网络iRMB(Improved Residual MobileNet Backbone),替换了原有的C2f模块,有效提升了模型的特征提取能力并降低了硬件计算成本。与原始YOLOv8模型相比,YOLOv8-RIC在自建图像数据集上的目标检测任务中,mAP(多类别平均精度)提高了6.2%,Precision(精确度)提高了12.7%。实验结果表明,该方法在复杂场景下对苹果树病害的检测具有较高的效率和鲁棒性,为精准农业的发展提供了有力支持。展开更多
基金supported by the National Natural Science Foundation of China(41561088 and 61501314)the Science&Technology Nova Program of Xinjiang Production and Construction Corps,China(2018CB020)
文摘Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.
基金funded by the National Key Research and Development Program of China (2016YFD0201137 and 2016YFE0101100)the Innovative Group Grant of the National Science Foundation of China (31421092)
文摘Apple occupies a dominant position in fruit production globally, and has become the main income source of local smallholder farmers in Luochuan County in the Loess Plateau area, one of the largest apple production areas in China. However, the annual productivity of apple orchards in this region remains low and has gradually declined over the years. The distinction and correlation of production constraints can contribute to the promotion of apple orchard productivity and the development of a sustainable orchard system. In the present study, survey data from 71 smallholder farmers were analyzed using a yield gap model to distinguish the production constraints and determine their correlation with the yield gap based on the structural equation model(SEM). The results indicated that the average apple yield in Luochuan County was 29.9 t ha^–1 yr^–1, while the attainable yield(Yatt;the highest yield obtained from the on-farm surveys) was 58.1 t ha^–1 yr^–1. The average explained and unexplainable yield gaps were 26.3 and 1.87 t ha^–1 yr^–1. According to the boundary line analysis, crop load,number of sprayings and base fertilizer N were the top three constraints on apple production in 9.8, 7.8 and 7.8% of the plots, respectively. Among the production constraints, crop load and fruit weight affected apple yield through direct pathways,whereas other constraints influenced apple yield through an indirect pathway based on the SEM, explaining 51% of the yield variance by all the main production constraints. These results can improve the current understanding of production constraints and contribute to the development of management strategies and policies for improving apple yield.
文摘Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have scarcely achieved the status of international recognition in commodity markets and research arena outside Africa. This paper presented a critical review of the status of IFT in the Tropical African sub-regions (of West Africa, Central Africa, East Africa, Southern Africa and the Indian Ocean Islands) in relation to the introduced naturalised fruit trees from tropical America and Asia, threats to the diversity and sustainable use of IFT, analysis of the opportunities and challenges of developing IFT, as well as targets for crop improvement of the rich IFT of Tropical Africa. Domestication programme via relevant vegetative propagation techniques for priority IFT of the sub-regions was examined and advocated, in addition to the adoption of complementary conservation strategies, including Field GeneBanks in the management of the continent’s IFT diversity.
文摘Biochar produced from pyrolysis of biomass such as wood,canopy,animal manure,and agricultural waste is recognized for its stability and for being a benefactor of soil health and plant growth.Its application in forestry is an area with growing research interest due to its ability to enhance soil physicochemical properties,including structure,water retention,and nutrient availability,thereby boosting plant growth,drought tolerance,and resistance to pests and diseases.However,the effectiveness of biochar varies based on factors like biochar type,application rate,soil type,and tree species.Potential risks associated with biochar use include nutrient immobilization,increased pH in alkaline soils,and enhanced leaching of toxic elements.Despite its promise,challenges such as knowledge gaps,lack of sitespecific studies,and concerns of economic viability hinder widespread adoption of biochar in forestry.This qualitative review compiles over 150 published works from the past two decades on biochar application in forestry.It assesses the impacts of biochar on soil health and tree crops,highlighting its potential to improve soil fertility and promote tree growth.The review identifies significant findings,such as the positive influence of biochar on soil and plant health and outlines existing knowledge gaps that need addressing.By synthesizing current research,the review proposes future directions to optimize biochar use in sustainable forestry management,emphasizing the need for tailored approaches and economic assessments to facilitate broader adoption.The findings underscore the potential role of biochar in enhancing forestry practices while calling for further studies to resolve uncertainties and improve its practical implementation.
文摘苹果作为全球重要的经济作物之一,其产量和质量直接受到病害的影响。为解决目前传统人工检测病害过程中主观性强、效率低,以及农业检测设备资源有限等问题,基于YOLOv8(You Only Look Once Version 8)提出了一种高效、轻量化的病害检测模型—YOLOv8-RIC。在YOLOv8的基础上对主干网络进行了优化,分别引入了轻量级卷积神经网络RGN(RepGhostNet)和改进型残差移动网络iRMB(Improved Residual MobileNet Backbone),替换了原有的C2f模块,有效提升了模型的特征提取能力并降低了硬件计算成本。与原始YOLOv8模型相比,YOLOv8-RIC在自建图像数据集上的目标检测任务中,mAP(多类别平均精度)提高了6.2%,Precision(精确度)提高了12.7%。实验结果表明,该方法在复杂场景下对苹果树病害的检测具有较高的效率和鲁棒性,为精准农业的发展提供了有力支持。
