分类： 计算机科学 >> 计算机科学的集成理论 提交时间： 2022-11-25 合作期刊: 《数据智能（英文）》
摘要： As the world population continues to increase, world food production is not keeping up. This means that to continue to feed the world, we will need to optimize the production and utilization of food around the globe. Optimization of a process on a global scale requires massive data. Agriculture is no exception, but also brings its own unique issues, based on how wide spread agricultural data are, and the wide variety of data that is relevant to optimization of food production and supply. This suggests that we need a global data ecosystem for agriculture and nutrition. Such an ecosystem already exists to some extent, made up of data sets, metadata sets and even search engines that help to locate and utilize data sets. A key concept behind this is sustainabilityhow do we sustain our data sets, so that we can sustain our production and distribution of food? In order to make this vision a reality, we need to navigate the challenges for sustainable data management on a global scale. Starting from the current state of practice, how do we move forward to a practice in which we make use of global data to have an impact on world hunger? In particular, how do we find, collect and manage the data? How can this be effectively deployed to improve practice in the field? And how can we make sure that these practices are leading to the global goals of improving production, distribution and sustainability of the global food supply? These questions cannot be answered yet, but they are the focus of ongoing and future research to be published in this journal and elsewhere.
分类： 计算机科学 >> 计算机应用技术 提交时间： 2019-11-23
摘要： Controlling weeds with reduced reliance on herbicides is one of the main challenges to move toward a more sustainable agriculture. Robotic weeding is a thought to be a viable way to reduce the environmental loading of agrochemicals while keeping the operation efficiency high. One of the key technologies for performing robotic weeding is automatic detection of crops and weeds in fields. This paper presents an overview on various methods for detecting plants based on machine vision, mainly concentrating on two main challenges: dealing with changing light and crop/weed discrimination. To overcome the first challenge, both physical and algorithmic methods have been proposed. Physical methods can result in a more cumbersome machine while algorithmic methods are less robust. For crop/weed discrimination, deep-learning-based methods have shown obvious advantages over traditional methods based on hand-crafted features. However, traditional methods still hold some merits that can be leveraged to deep-learning-based methods. With the fast development of hardware technologies, researchers should take full advantage of advanced hardware to ease the algorithm design. In the future, the identification of crops and weeds can be more accurate and fine-grained with the support of online databases and computing resources based on the advances in artificial intelligence and communication technologies.
分类： 生物学 >> 植物学 >> 应用植物学 提交时间： 2016-05-04
Carmenza Robledo-Abad
Hans-Jörg Althaus
Göran Berndes
Simon Bolwig
Esteve Corbera
a de Barcelona
Felix Creutzig
John Garcia-Ulloa
Anna Geddes
Jay S. Gregg
Helmut Haberl
Susanne Hanger
Richard J. Harper
Carol Hunsberger
Rasmus K. Larsen
Christian Lauk
Stefan Leitner
Johan Lilliestam
Hermann Lotze-Campen
Bart Muys
摘要： The possibility of using bioenergy as a climate change mitigation measure has sparked a discussion of whether and how bioenergy production contributes to sustainable development. We undertook a systematic review of the scientific literature to illuminate this relationship and found a limited scientific basis for policymaking. Our results indicate that knowledge on the sustainable development impacts of bioenergy production is concentrated in a few well-studied countries, focuses on environmental and economic impacts, and mostly relates to dedicated agricultural biomass plantations. The scope and methodological approaches in studies differ widely and only a small share of the studies sufficiently reports on context and/or baseline conditions, which makes it difficult to get a general understanding of the attribution of impacts. Nevertheless, we identified regional patterns of positive or negative impacts for all categories – environmental, economic, institutional, social and technological. In general, economic and technological impacts were more frequently reported as positive, while social and environmental impacts were more frequently reported as negative (with the exception of impacts on direct substitution of GHG emission from fossil fuel). More focused and transparent research is needed to validate these patterns and develop a strong science underpinning for establishing policies and governance agreements that prevent/mitigate negative and promote positive impacts from bioenergy production.
分类： 管理学 >> 管理学其他学科 提交时间： 2022-11-25 合作期刊: 《Economics & Management Review》
摘要： Agricultural green sustainable development has become an important strategy in every country, and whether this strategy can be realized depends on the development and popularization of the model of planting and breeding combined circular agriculture. Based on the related theories, a three-dimensional structure analysis model including the types of participants, project operation mode, planting and breeding structure and benefit is established in this paper. And by examining the typical case of green agriculture in China, in this study, three green farming models, namely, the animal-plant cycle model dominated by two agents, the three-dimensional cycle model with multi agents, and the three-stage cycle model dominated by individual investors, were summarized. Finally, through the comparison and induction of the models, the existing problems and optimization direction of the current basic models of planting and breeding cycle agriculture were put forward.
分类： 地球科学 >> 地理学 提交时间： 2021-02-10 合作期刊: 《干旱区科学》
摘要： Crop residue is a major source of soil organic matter; therefore, application of crop straw to soil contributes to the sustainable development of organic agriculture. To better understand the transformation of crop straw in orchard soils, we investigated the relationship between the characteristics of straw decomposition and functional diversity of associated microbial communities in a long-term peach orchard, China. Mesh bags, each containing 30 g of corn or bean straw, were buried at a soil depth of 20 cm in a 12-year-old peach orchard for 360 d (October 2011–October 2012). Three treatments were applied, i.e., fresh corn straw, fresh corn straw with nitrogen fertilizer (urea, 10.34 g/kg), and fresh bean straw. Changes in straw residual rate, straw water content and soil conditions were monitored after treatment. The functional diversity of straw-associated microbial communities was analyzed by the Biolog-Eco microplate assay. During the decomposition process, straw residual rates did not vary considerably from 10 d (30.4%–45.4%) to 360 d (19.0%–30.3%). Irrespective of nitrogen addition, corn straw decomposed faster than bean straw. Corn straw with nitrogen fertilizer yielded the highest average well color development (AWCD) values (1.11–1.67), followed by corn straw (1.14–1.68) and bean straw (1.18–1.62). Although the AWCD values did not differ significantly among the three treatments, substantial differences occurred across various time periods of the decomposition process (P<0.01). In terms of carbon source utilization, the dominant microbial groups fed mainly on saccharides. Hard-to-decompose substances gradually accumulated in the middle and late stages of straw decomposition. Of the six categories of carbon sources tested, the utilization rate of aromatics was the lowest with corn straw, whereas that of polymers was the lowest with bean straw. Among different treatments, straw residual rate was negatively correlated to soil available phosphorous, soil available potassium and soil temperature (P<0.05), but not to soil water content. In some cases (corn straw with or without nitrogen fertilizer), straw residual rate was negatively correlated to straw water content, amino acid utilization and carboxylic acid utilization, and positively correlated with microbial species richness and evenness (P<0.05). Microbial community associated with corn and bean straw decomposition in soil was respectively dominated by aromatic- and polymer-metabolizing groups during the middle and late stages of this process, which could reduce the stability of microbial community structure and decrease the rate of straw decomposition in the fruit tree orchard.
分类： 生物学 >> 生态学 提交时间： 2017-04-22
摘要： 摘要：田村三郎（1917-2015），原日本东京大学农学部教授，日本学士院会员。自 1957摘要：田村三郎（1917-2015），原日本东京大学农学部教授，日本学士院会员。自 1957年以来田村便与中国科学院保持着长久的联系。1978 年以后，更与中国科学院在农业和环境领域展开了长期的合作研究，还参与了中国农业现代化的讨论。本文以田村为案例，利用档案、报刊、传记等文献资料，在回顾田村三郎与中国科学院交往与合作研究历程的同时，重点关注田村关于中国农业现代化的论述与实践，并初步探讨田村三郎与中国科学院合作成功的原因。 现代化的过程就是传统与现代、东方与西方、区域与全球的互动过程。如何用现代农业去改造传统农业，把东方智慧与西方科学有效结合，将区域的特性和全球化的挑战进行调适，是现代化进程中必须解决的问题。田村把他对中国农业现状的理解和日本农业的历史经验，运用于中国农业现代化实践之中，构成了本文所谓的“田村经验”。这些经验值得我们在处理诸如农业的全球化及其区域性和共性问题时汲取。
分类： 机械工程 >> 机械制造自动化 提交时间： 2018-03-16
摘要： A machine-vision-based method of locating crops is described in this research. This method was used to provide real-time positional information of crop plants for a mechanical intra-row weeding robot. Within the normalized red, green, and blue chromatic coordinates (rgb), a modified excess green feature (g-r>T & g-b>T) was used to segment plant material from back ground in color images. The threshold T was automatically selected by the maximum variance (OTSU) algorithm to cope with variable natural light. Taking into account the geometry of the camera arrangement and the crop row spacing, the target regions covering the crop rows were defined based on a pinhole camera model. According to the statistical variation in the pixel histogram in each target region, locations of the crop plants were initially estimated. To obtain the accurate locations of crops, median filtering was conducted locally in the bounding boxes of the crops close to the bottom of the images. For the lateral guidance of the robot, a novel method of calculating lateral offset was proposed based on a simplified match between a template and the detected crops. Field experiments were conducted under three different illumination conditions. The results showed that the accurate identification rates on lettuce, cauliflower and maize were all above 95%. The positional error as within ±15 mm, and the average processing time for a 640×480 image was 31 ms. The method was adequate to meet the technical requirement of the weeding robot, and laid a foundation for robotic weeding in commercial production system.
分类： 生物学 >> 植物学 >> 植物生态学和植物地理学 提交时间： 2016-05-04
摘要： Agave species are high-yielding crassulacean acid metabolism (CAM) plants, some of which are grown commercially and recognized as potential bioenergy species for dry regions of the world. This study is the first field trial of Agave species for bioenergy in the United States, and was established to compare the production of Agave americana with the production of Agave tequilana and Agave fourcroydes, which are produced commercially in Mexico for tequila and fiber. The field trial included four experimental irrigation levels to test the response of biomass production to water inputs. After 3years, annual production of healthy A.americana plants reached 9.3Mgdrymassha1yr1 (including pup mass) with 530mm of annual water inputs, including both rainfall and irrigation. Yields in the most arid conditions tested (300mmyr1 water input) were 2.04.0Mgdrymassha1yr1. Agave tequilana and Agave fourcroydes were severely damaged by cold in the first winter, and produced maximum yields of only 0.04Mgha1yr1 and 0.26Mgha1yr1, respectively. The agave snout weevil (Scyphophorus acupunctatus) emerged as an important challenge for A.americana cropping, killing a greater number of plants in the higher irrigation treatments. Physiological differences in A.americana plants across irrigation treatments were most evident in the warmest season, with gas exchange beginning up to 3h earlier and water use efficiency declining in treatments with the greatest water input (780mmyr1 water input). Yields were lower than previous projections for Agave species, but results from this study suggest that A.americana has potential as a bioenergy crop and would have substantially reduced irrigation requirements relative to conventional crops in the southwestern USA. Challenges for pest management and harvesting must still be addressed before an efficient production system that uses Agave can be realized.
分类： 地球科学 >> 水文学 提交时间： 2018-07-05 合作期刊: 《干旱区科学》
摘要： The Palmer drought severity index (PDSI), standardized precipitation index (SPI), and standardized precipitation evapotranspiration index (SPEI) are used worldwide for drought assessment and monitoring. However, substantial differences exist in the performance for agricultural drought among these indices and among regions. Here, we performed statistical assessments to compare the strengths of different drought indices for agricultural drought in the North China Plain. Small differences were detected in the comparative performances of SPI and SPEI that were smaller at the long-term scale than those at the short-term scale. The correlation between SPI/SPEI and PDSI considerably increased from 1- to 12-month lags, and a slight decreasing trend was exhibited during 12- and 24-month lags, indicating a 12-month scale in the PDSI, whereas the SPI was strongly correlated with the SPEI at 1- to 24-month lags. Interestingly, the correlation between the trend of temperature and the mean absolute error and its correlation coefficient both suggested stronger relationships between SPI and the SPEI in areas of rapid climate warming. In addition, the yielddrought correlations tended to be higher for the SPI and SPEI than that for the PDSI at the station scale, whereas small differences were detected between the SPI and SPEI in the performance on agricultural systems. However, large differences in the influence of drought conditions on the yields of winter wheat and summer maize were evident among various indices during the crop-growing season. Our findings suggested that multi-indices in drought monitoring are needed in order to acquire robust conclusions.
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