As China accommodates the biggest population in the world, the development of agriculture, particularly the production of grain and food, has been considered to be a primary important issue of the country. The central...As China accommodates the biggest population in the world, the development of agriculture, particularly the production of grain and food, has been considered to be a primary important issue of the country. The central government of China has long placed the first priority to the development of agriculture in the Nation’s economy, and this policy will be carded out persistently. Quite naturally, the "grain problem" has not only become a focus of the country, but also attracted the attention of the inter-展开更多
Based on the photosynthesis-respiration reversible reaction and the available statistics, we attempted to quantify the planetary seasonal exchanges of CO<sub>2</sub> between air and water from 1970 and com...Based on the photosynthesis-respiration reversible reaction and the available statistics, we attempted to quantify the planetary seasonal exchanges of CO<sub>2</sub> between air and water from 1970 and compared them to the glacial ACC cycles as reported from ice cores archives. In 2020, the overall continental absorption (AW) was 8.0 giga tonnes of carbon per year (GtC/y). Emissions into the atmosphere (EW) resulting from mineral degradation by respiration and combustion of biomass and fossil hydrocarbons were 14.7 GtC/y, an increase of 2.4% per year since 1970. The continental surplus balance (-AW+EW) of 6.7 GtC/y was shared between the atmosphere, which received 5.1 GtC/y (GATM), and the ocean which absorbed 1.6 GtC/y. This ocean contribution (OC) corresponded to 17% of the 9.2 GtC/y emissions by combustion of fossil hydrocarbons (EFOS). Analysis of the ACC oscillations during 2020 in the northern hemisphere showed that the ocean absorbed 11.1 GtC during the warm season and outgassed 9.5 GtC during the cold season. Assuming proportionality to world population, the ACC, 414 parts per million (ppm) in 2021, would reach 584 ppm in 2080, still growing at a rate of 0.6% per year. The gain of atmospheric CO<sub>2</sub> (GATM) and its absorption by the ocean (OC) were expected to peak at 7.0 and 2.2 GtC/y, respectively, in 2080. This increase in the availability of atmospheric CO<sub>2</sub> resulted in improved yields of agriculture which more than compensated for the reduction by half of food-producing areas per capita from 1970.展开更多
This article assesses the impacts of agroecological technologies adoption on the agricultural yields and incomes for millet and cowpea producers in Niger from both Maradi and Zinder regions. For this purpose, a set of...This article assesses the impacts of agroecological technologies adoption on the agricultural yields and incomes for millet and cowpea producers in Niger from both Maradi and Zinder regions. For this purpose, a set of descriptive statistics methods are applied to data collected from 1950 producers from 80 villages. Results indicate that the density of semi, HPK variety, compost and IT 90 variety are the most adopted agroecological technologies with respective adoption rates of 87%, 69%, 64.3% and 64%. Moreover, results show that millet producers that adopted agro-ecological technologies have on average multiplied by 2.00 and 2.96 times their production, in Zinder and Maradi regions respectively. Besides, findings reveal that cowpea producers that adopted agro-ecological technologies have on average multiplied by 2.00 and 3.21 times their production, in Zinder and Maradi regions respectively. Finally, results support that the improvement in millet and cowpea yields has led to increase in producers’ total income by 2 and 3 times respectively in Zinder and Maradi regions. Since agroecological technologies improve agricultural yields and income, we suggest policy makers to recommend their adoption and diffusion.展开更多
Iraq is part of the Fertile Crescent with the two large rivers:Tigris and Euphrates and their tributaries that secure the required quantity and quality of water to the Iraqi population for their different uses;includi...Iraq is part of the Fertile Crescent with the two large rivers:Tigris and Euphrates and their tributaries that secure the required quantity and quality of water to the Iraqi population for their different uses;including agriculture,industry,and other domestic requirements.During the last decades,however,the quantity and quality of water in these rivers decreased causing water scarcity in the country.This scarcity is having severe impacts on food security in Iraq since large cultivated areas in different parts of the country that grow different agricultural products have been abandoned due to lack of water.The worsening situation is attributed mainly to global climate changes including decreasing rainfall amounts,increase in air temperature,and insufficient water inflows in the two main rivers and their tributaries.This last issue is exasperated by the unfair water sharing policies of the riparian countries namely Turkey and Iran.In writing this article relevant data from different sources were used.Numerous published reports and papers dealing with this important issue were consulted,while at the same time,the long experience of the authors in these very important issues was also drawn upon to elucidate the difficulties that are current today and those expected in the future in this field.展开更多
Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to...Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to produce it through solid state reaction from 900℃ to 1300℃. The conducted reaction was monitored by XRD step by step. Amount of Wollastonite formed at every temperature was also studied to some extent. Analyses of the obtained data indicated that the target mineral formation was quite effective and almost proportional to a rise in temperature up to 1200℃. The results from both, XRD and chemical analysis were found in fair agreement with one another展开更多
Deep Learning(DL),a type of Machine Learning,has gained significant interest in many fields,including agriculture.This paper aims to shed light on deep learning techniques used in agriculture for abiotic and biotic st...Deep Learning(DL),a type of Machine Learning,has gained significant interest in many fields,including agriculture.This paper aims to shed light on deep learning techniques used in agriculture for abiotic and biotic stress detection in fruits and vegetables,their benefits,and the challenges faced by users.Scientific papers were collected from Web of Science,Scopus,Google Scholar,Springer,and Directory of Open Access Journals(DOAJ)using combinations of specific keywords such as:’Deep Learning’OR’Artificial Intelligence’in combination with fruit disease’,vegetable disease’,‘fruit stress',OR‘vegetable stress'following PRISMA guidelines.From the initial 818 papers identified using the keywords,132 were reviewed after excluding books,reviews,and the irrelevant.The recovered scientific papers were from 2003 to 2022;93%addressed biotic stress on fruits and vegetables.The most common biotic stresses on species are fungal diseases(grey spots,brown spots,black spots,downy mildew,powdery mildew,and anthracnose).Few studies were interested in abiotic stresses(nutrient deficiency,water stress,light intensity,and heavy metal contamination).Deep Learning and Convolutional Neural Networks were the most used keywords,with GoogleNet(18.28%),ResNet50(16.67%),and VGG16(16.67%)as the most used architectures.Fifty-two percent of the data used to compile these models come from the fields,followed by data obtained online.Precision problems due to unbalanced classes and the small size of some databases were also analyzed.We provided the research gaps and some perspectives from the reviewed papers.Further research works are required for a deep understanding of the use of machine learning techniques in fruit and vegetable studies:collection of large datasets according to different scenarios on fruit and vegetable diseases,evaluation of the effect of climatic variability on the fruit and vegetable yield using AI methods and more abiotic stress studies.展开更多
Drought stress affects plant growth and causes significant issues in meeting global demand for food crops and fodder.Drought can cause physiological,physicochemical,and morphological changes in plants,which negatively...Drought stress affects plant growth and causes significant issues in meeting global demand for food crops and fodder.Drought can cause physiological,physicochemical,and morphological changes in plants,which negatively affects plant growth and productivity.To combat this under the increasing global threat of water shortage and rapid population expansion,it is crucial to develop strategies to meet global food demands.Plant growth-promoting rhizobacteria(PGPR)may provide a safe solution to enhancing crop yields through various mechanisms.These soil bacteria can provide drought tolerance to crop plants,allowing them to survive and thrive in water-scarce conditions.Productions of phytohormones,free radical-scavenging enzymes,and stress-combating enzymes that can increase tolerance to drought-induced stress are key features of plant-associated microbial communities.This review summarizes the beneficial properties of microbes that help plants tolerate water scarcity and highlights the bacterial mechanisms that enhance drought tolerance in plants.展开更多
Premium ratemaking is an important issue to guarantee insurance balance of payments. Most ratemaking methods require large samples of long-term loss data or farm-level yield data, which are often unavailable in develo...Premium ratemaking is an important issue to guarantee insurance balance of payments. Most ratemaking methods require large samples of long-term loss data or farm-level yield data, which are often unavailable in developing countries. This study develops a crop insurance ratemaking method with survey data. The method involves a questionnaire survey on characteristic yield information(average yield, high yield, and low yield) of farming households’ cropland. After compensating for random error, the probability distributions of farm-level yields are simulated with characteristic yields based on the linear additive model. The premium rate is calculated based on Monte Carlo yield simulation results. This method was applied to Dingxing County, North China to arrive at the insurance loss cost ratio and calculate the necessary premium rate. The method proposed in this study could serve as a feasible technique for crop insurance ratemaking inregions that lack sufficient long-term yield data, especially in developing countries with smallholder agriculture.展开更多
文摘As China accommodates the biggest population in the world, the development of agriculture, particularly the production of grain and food, has been considered to be a primary important issue of the country. The central government of China has long placed the first priority to the development of agriculture in the Nation’s economy, and this policy will be carded out persistently. Quite naturally, the "grain problem" has not only become a focus of the country, but also attracted the attention of the inter-
文摘Based on the photosynthesis-respiration reversible reaction and the available statistics, we attempted to quantify the planetary seasonal exchanges of CO<sub>2</sub> between air and water from 1970 and compared them to the glacial ACC cycles as reported from ice cores archives. In 2020, the overall continental absorption (AW) was 8.0 giga tonnes of carbon per year (GtC/y). Emissions into the atmosphere (EW) resulting from mineral degradation by respiration and combustion of biomass and fossil hydrocarbons were 14.7 GtC/y, an increase of 2.4% per year since 1970. The continental surplus balance (-AW+EW) of 6.7 GtC/y was shared between the atmosphere, which received 5.1 GtC/y (GATM), and the ocean which absorbed 1.6 GtC/y. This ocean contribution (OC) corresponded to 17% of the 9.2 GtC/y emissions by combustion of fossil hydrocarbons (EFOS). Analysis of the ACC oscillations during 2020 in the northern hemisphere showed that the ocean absorbed 11.1 GtC during the warm season and outgassed 9.5 GtC during the cold season. Assuming proportionality to world population, the ACC, 414 parts per million (ppm) in 2021, would reach 584 ppm in 2080, still growing at a rate of 0.6% per year. The gain of atmospheric CO<sub>2</sub> (GATM) and its absorption by the ocean (OC) were expected to peak at 7.0 and 2.2 GtC/y, respectively, in 2080. This increase in the availability of atmospheric CO<sub>2</sub> resulted in improved yields of agriculture which more than compensated for the reduction by half of food-producing areas per capita from 1970.
文摘This article assesses the impacts of agroecological technologies adoption on the agricultural yields and incomes for millet and cowpea producers in Niger from both Maradi and Zinder regions. For this purpose, a set of descriptive statistics methods are applied to data collected from 1950 producers from 80 villages. Results indicate that the density of semi, HPK variety, compost and IT 90 variety are the most adopted agroecological technologies with respective adoption rates of 87%, 69%, 64.3% and 64%. Moreover, results show that millet producers that adopted agro-ecological technologies have on average multiplied by 2.00 and 2.96 times their production, in Zinder and Maradi regions respectively. Besides, findings reveal that cowpea producers that adopted agro-ecological technologies have on average multiplied by 2.00 and 3.21 times their production, in Zinder and Maradi regions respectively. Finally, results support that the improvement in millet and cowpea yields has led to increase in producers’ total income by 2 and 3 times respectively in Zinder and Maradi regions. Since agroecological technologies improve agricultural yields and income, we suggest policy makers to recommend their adoption and diffusion.
文摘Iraq is part of the Fertile Crescent with the two large rivers:Tigris and Euphrates and their tributaries that secure the required quantity and quality of water to the Iraqi population for their different uses;including agriculture,industry,and other domestic requirements.During the last decades,however,the quantity and quality of water in these rivers decreased causing water scarcity in the country.This scarcity is having severe impacts on food security in Iraq since large cultivated areas in different parts of the country that grow different agricultural products have been abandoned due to lack of water.The worsening situation is attributed mainly to global climate changes including decreasing rainfall amounts,increase in air temperature,and insufficient water inflows in the two main rivers and their tributaries.This last issue is exasperated by the unfair water sharing policies of the riparian countries namely Turkey and Iran.In writing this article relevant data from different sources were used.Numerous published reports and papers dealing with this important issue were consulted,while at the same time,the long experience of the authors in these very important issues was also drawn upon to elucidate the difficulties that are current today and those expected in the future in this field.
文摘Wollastonite, a mineral of wide industrial applications was synthesised from rice husk ash silica and limestone. A number of raw batches consisting of these starting materials, in 1:1 molar ratio, were heat treated to produce it through solid state reaction from 900℃ to 1300℃. The conducted reaction was monitored by XRD step by step. Amount of Wollastonite formed at every temperature was also studied to some extent. Analyses of the obtained data indicated that the target mineral formation was quite effective and almost proportional to a rise in temperature up to 1200℃. The results from both, XRD and chemical analysis were found in fair agreement with one another
基金the German Academic Exchange Service(DAAD)and the scholarship program“Artificial Intelligence for Development(AI4D)in Africa”the International Development Research Centre(IDRC)+1 种基金the Swedish International Development Cooperation Agency(SIDA)the African Centre for Technology Studies(ACTS).
文摘Deep Learning(DL),a type of Machine Learning,has gained significant interest in many fields,including agriculture.This paper aims to shed light on deep learning techniques used in agriculture for abiotic and biotic stress detection in fruits and vegetables,their benefits,and the challenges faced by users.Scientific papers were collected from Web of Science,Scopus,Google Scholar,Springer,and Directory of Open Access Journals(DOAJ)using combinations of specific keywords such as:’Deep Learning’OR’Artificial Intelligence’in combination with fruit disease’,vegetable disease’,‘fruit stress',OR‘vegetable stress'following PRISMA guidelines.From the initial 818 papers identified using the keywords,132 were reviewed after excluding books,reviews,and the irrelevant.The recovered scientific papers were from 2003 to 2022;93%addressed biotic stress on fruits and vegetables.The most common biotic stresses on species are fungal diseases(grey spots,brown spots,black spots,downy mildew,powdery mildew,and anthracnose).Few studies were interested in abiotic stresses(nutrient deficiency,water stress,light intensity,and heavy metal contamination).Deep Learning and Convolutional Neural Networks were the most used keywords,with GoogleNet(18.28%),ResNet50(16.67%),and VGG16(16.67%)as the most used architectures.Fifty-two percent of the data used to compile these models come from the fields,followed by data obtained online.Precision problems due to unbalanced classes and the small size of some databases were also analyzed.We provided the research gaps and some perspectives from the reviewed papers.Further research works are required for a deep understanding of the use of machine learning techniques in fruit and vegetable studies:collection of large datasets according to different scenarios on fruit and vegetable diseases,evaluation of the effect of climatic variability on the fruit and vegetable yield using AI methods and more abiotic stress studies.
文摘Drought stress affects plant growth and causes significant issues in meeting global demand for food crops and fodder.Drought can cause physiological,physicochemical,and morphological changes in plants,which negatively affects plant growth and productivity.To combat this under the increasing global threat of water shortage and rapid population expansion,it is crucial to develop strategies to meet global food demands.Plant growth-promoting rhizobacteria(PGPR)may provide a safe solution to enhancing crop yields through various mechanisms.These soil bacteria can provide drought tolerance to crop plants,allowing them to survive and thrive in water-scarce conditions.Productions of phytohormones,free radical-scavenging enzymes,and stress-combating enzymes that can increase tolerance to drought-induced stress are key features of plant-associated microbial communities.This review summarizes the beneficial properties of microbes that help plants tolerate water scarcity and highlights the bacterial mechanisms that enhance drought tolerance in plants.
基金supported by the State Key Scientific Program of China (973 project): Global Change, Environmental Risk and Its Adaptation Paradigms (No. 2012CB955403)
文摘Premium ratemaking is an important issue to guarantee insurance balance of payments. Most ratemaking methods require large samples of long-term loss data or farm-level yield data, which are often unavailable in developing countries. This study develops a crop insurance ratemaking method with survey data. The method involves a questionnaire survey on characteristic yield information(average yield, high yield, and low yield) of farming households’ cropland. After compensating for random error, the probability distributions of farm-level yields are simulated with characteristic yields based on the linear additive model. The premium rate is calculated based on Monte Carlo yield simulation results. This method was applied to Dingxing County, North China to arrive at the insurance loss cost ratio and calculate the necessary premium rate. The method proposed in this study could serve as a feasible technique for crop insurance ratemaking inregions that lack sufficient long-term yield data, especially in developing countries with smallholder agriculture.