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Weeding is at the heart of agriculture. Today, using herbicides is unavoidable in conventional agriculture. However, increasing ecological awareness, the need to reduce carbon dioxide emissions, and the pursuit of sustainable food have driven industries and academics to explore new approaches for growing and protecting crops. In this context, smart spot sprayers emerge as a highly innovative alternative to broadcast treatments, which overuse pesticides, and mechanical weeding, which is limited by restrictive application conditions. Using artificial intelligence (AI) for plant recognition and ultra-precise spraying technology, herbicides are applied directly to weeds with minimal overspray, reducing their use by 90% compared to conventional methods. Spot sprayers' narrowly targeted spray limits chemicals' contact with the crop, resulting in low phytotoxicity, preserving natural crop development while maximizing yield potential. In addition, site-specific application increases the selectivity of chemical products artificially, enabling more concentrated mixtures to be used. Also, AI enables the selective application of non-selective molecules, supporting their use in established cultures. These characteristics open new opportunities for effective weed control where the traditional solutions fall short. This publication demonstrates the potential of the ultra-precise smart spot sprayer ARA in weed management in onion and sugar beet crops. Although comparing the overall performance of ARA with other smart spot sprayers on the market cannot be done in this article, this technology's potential in rendering weed management on farms more effective, sustainable, and saving labor without compromising yield is nevertheless indicated. [ABSTRACT FROM AUTHOR]

This article explores the backend processes of libraries to remove materials after the deselection decisions are made. It brings into focus how administration decisions made at the outset of a project have a continuing impact on workflow and timeline of a project's completion. It highlights lessons learned from two withdraw projects with differing workflows. Finally, it poses important questions for other libraries to answer when planning large withdraw projects at their own institutions. [ABSTRACT FROM AUTHOR]

More than 40% of the total oil palm area in Indonesia is owned and managed by smallholders. For large plantations, guidelines are available on so-called 'best management practices', which should give superior yields at acceptable costs when followed carefully. We tested a subset of such practices in a sample of smallholder plantations, aiming to increase yields and profitability. We implemented improved practices (weeding, pruning, harvesting, and fertiliser application) in 14 smallholder plantations of 13–15 years after planting in Jambi province (Sumatra) and in West-Kalimantan province (Kalimantan) for a duration of 3 to 3.5 years. During this period, we recorded yields, measured palm leaf parameters and analysed leaf nutrient contents. Yield recording then continued for an additional two years. In the treatment plots, the yields did not increase significantly, but the size of the bunches and the size of the palm leaves increased significantly and substantially. The tissue nutrient concentrations also increased significantly, although after three years, the potassium concentrations in the rachis were still below the critical value. Because of the absence of yield increase and the additional costs for fertiliser inputs, the net profit of implementing better management practices was negative, and 'business as usual' was justified financially. Some practices, such as harvesting at 10-day intervals and the weeding of circles and paths, were received positively by those farmers who could implement them autonomously, and were applied beyond the experiment. It is challenging to find and implement intensification options that are both sustainable and profitable, that have a substantial impact on yield, and that fit in the smallholders' realities. On-farm experimentation and data collection are essential for achieving sustainable intensification in smallholder oil palm plantations. [ABSTRACT FROM AUTHOR]

The library's renovation and stacks-books reduction projects began more than 1000 days ago. During these past 4 years, the projects suffered numerous starts and stops as those involved changed due to staff turnover in the library caused by the pandemic, the elimination of positions due to lower enrollment, the closure of the physical library caused by the pandemic, and shifting leadership priorities. First came the campus construction initiative that reduced library space. Then I introduce myself as the source main source of information for the article. Next, I lead you through the progression of the projects by examining the projects' goals and objectives, assessing the projects, assigning roles for the project, and determining the project's costs. Finally, I conclude with the challenges I faced and the lessons I learned by fostering change from this ongoing project management experience. [ABSTRACT FROM AUTHOR]

Between 2017 and 2019, I created three temporary artistic interventions in public spaces in which passers-by could discover, interact with or ignore different materials related to libraries as social, public systems. During my work with the first, Expired Outdoors (2017), serendipity emerged as a principle I became interested in exploring further. In two consecutive installations, serendipity gradually manifested itself both as an interface between my installations and their audience and as a creative strategy guiding my choices of contexts and materials. Upon invitation from editor Olga Schmedling, in this article I discuss aspects of serendipity in the three projects, proposing to understand serendipity as instances of interruption rather than as accidental discovery. [ABSTRACT FROM AUTHOR]

In Hokkaido, northern Japan, bareroot Sakhalin fir seedlings are conventionally planted in spring and fall, following strip site preparation that alternates managed and unmanaged strips. However, this method requires seven years of weeding due to encroachment of evergreen dwarf bamboo. Given diminishing forest labor availability, a shortage of workers for planting and weeding operations has become a problem in reforestation following clearcutting. We examined whether comprehensive mechanical site preparation (MSP) could reduce weeding frequency by preventing regrowth of dwarf bamboo and whether container seedlings could extend the planting season into summer. Over eight years, the survival and growth of summer-planted bareroot and container seedlings were examined on a fully MSP-treated site with only one weeding operation in the fifth year. Full-site MSP resulted in a shift of the vegetation from dwarf bamboo to deciduous plants, leading to high survival and growth rates of Sakhalin fir seedlings despite minimal weeding. Container seedlings exhibited superior establishment and maintained higher survival rates over eight years than bareroot seedlings. However, planting on the forwarder trail decreased seedling growth, and ultimately decreased survival under rare summer drought. Our findings indicate that container seedling summer planting and full-site MSP may represent an alternative approach to reforestation of Sakhalin fir, potentially reducing the need for weeding and extending the planting season. [ABSTRACT FROM AUTHOR]

Weeding is at the heart of agriculture. Today, using herbicides is unavoidable in conventional agriculture. However, increasing ecological awareness, the need to reduce carbon dioxide emissions, and the pursuit of sustainable food have driven industries and academics to explore new approaches for growing and protecting crops. In this context, smart spot sprayers emerge as a highly innovative alternative to broadcast treatments, which overuse pesticides, and mechanical weeding, which is limited by restrictive application conditions. Using artificial intelligence (AI) for plant recognition and ultra-precise spraying technology, herbicides are applied directly to weeds with minimal overspray, reducing their use by 90% compared to conventional methods. Spot sprayers' narrowly targeted spray limits chemicals' contact with the crop, resulting in low phytotoxicity, preserving natural crop development while maximizing yield potential. In addition, site-specific application increases the selectivity of chemical products artificially, enabling more concentrated mixtures to be used. Also, AI enables the selective application of non-selective molecules, supporting their use in established cultures. These characteristics open new opportunities for effective weed control where the traditional solutions fall short. This publication demonstrates the potential of the ultra-precise smart spot sprayer ARA in weed management in onion and sugar beet crops. Although comparing the overall performance of ARA with other smart spot sprayers on the market cannot be done in this article, this technology's potential in rendering weed management on farms more effective, sustainable, and saving labor without compromising yield is nevertheless indicated.

Mobile robotic technologies are emerging in agriculture in recent years, driven by labor shortages, the need of precision farm management, and the improvement of farmers' quality of life. Mobile robotic technologies, both aerial and ground, have been considered as one of the most important and promising solutions to address agricultural challenges. Nevertheless, the implementation rate in farms is still low. The aim of this study was to evaluate the performance of a mobile agricultural ground robot to assess its possible implementation in the farm environment. The mobility performances as well as the energy consumption of the mobile robot were evaluated considering different interaction systems (teleoperated, autonomous driving) and application areas (weeding, tilling). The results show that the forward speed of the tested mobile robot is affected by the towed load, up to 230 kg, and that the robot could be driven continuously for 2 h in the field without decreasing its performances at a maximum speed between 0.71–0.77 m s-1. The autonomy of the tested robot is limited, but this is mainly due to the battery technology used. The mobile robot effectively tow implements for weeding and tilling operations managing grass with a single pass (40 % weed removal) and improving soil bulk density. The average energy consumption across the different settings was about 1.43 kWh for each hour of use. Moreover, although the RTK-GNSS autonomous navigation used was a low-cost system, the results showed a good accuracy, which allowed the mobile robot to navigate autonomously in the 2 m inter-row of the vineyard. Finally, the working capacity of the mobile robots, considering the implements used, is on average 0.29 ha h-1. This study provides further evidence for the possible use of ground mobile robot in agriculture to carry out autonomous or semi-autonomous operations.

AbstractA field experiment replicated over two seasons examined allelopathic effects of eleven sorghum accessions with known sorgoleone content on sorghum growth and yield, weed density and biomass at Panmure Experiment Station, in Shamva, Zimbabwe in the 2017/2018 summer and in late winter to summer in 2018. The trial was a 2 × 11 factorial in a randomized complete block design plus two control treatments replicated thrice. Factor A was weeding regime with two levels: clean weeding and no weeding. Factor B were 11 sorghum accessions. There was a significant sorghum accession × weeding regime interaction effect (p 0.05) between sorgoleone content and weed density and biomass, suggesting that sorgoleone may not instantly cause allelopathic effects on weeds upon its release from root hairs because it is strongly sorbed in soil, and inhibition of density and biomass might have been caused by other allelopathic compounds. Future research should trace uptake and translocation of allelopathic compounds to target sites of receiver plants, and demonstrate that subsequent damage symptoms are caused by the allelopathic compounds.

The Cheadle Center at UCSB manages the North Campus Open Space (NCOS), which is a project that has restored 136 acres of upland and wetland habitats that existed before the area was converted into the Ocean Meadows Golf Course in the 1960s. The NCOS restoration project began in 2017 with a fine-scale grading of the site in order to recreate the salt marsh and use the excavated soil to rebuild the upland habitats to the southwest, which are now called the NCOS Mesa. In addition to re-establishing native biodiversity, a key goal of the restoration is to utilize the site as an educational, scientific, and recreational resource. This archived version of the December 2022 newsletter includes updates on how recent rainfall has influenced NCOS. The feature story focuses on bird diversity and efforts to sustain populations of rare and/or threatened breeding birds. Community photos include Hooded Merganser (Lophodytes cucullatus), Canada Goose (Branta canadensis), California Ebony Tarantula (Aphonopelma eutylenum), American Bittern (Botaurus lentiginosus), Northern Harrier (Circus hudsonius), and Cooper’s Hawk (Accipiter cooperii).

Agriculture is an important sector of the European Union in social, economic and environmental terms. To ensure the sustainability of the sector, improvements are needed in key operations. Weeding is one of the most important activities affecting farm productivity, farmer safety, food safety and security, and the state of the environment. New technical and organizational solutions are needed to achieve the goals of the EU policy for sustainable agriculture. One of the advanced techniques is laser-based weed control. It is important to fully understand the impact of the introduction of these techniques on markets and agricultural practices in the context of sustainability. For this reason, a social life cycle analysis (S-LCA) was carried out. The method applied in the study was based on a participatory approach. The assessment was carried out from three perspectives: the general society, the farmers and the business perspective in relation to agriculture. Expert interviews based on questionnaires and workshops were conducted to gather opinions on the impact of new laser technology on specific aspects of its implementation. The results show generally positive effects from all perspectives, especially from the farmers' perspective. From the farmers' point of view, the most favored factors influencing the widespread introduction of WLAT are the economic consequences, the most important of which are the production costs associated with the introduction of the new technology. According to business experts, the perspective of business development, with particular emphasis on new prospects for businesses and development, is the most important factor. The quality of life and the environment are most valued by society. [ABSTRACT FROM AUTHOR]

Introduction: Polyethylene mulch is a kind of inorganic mulch widely used in agriculture. The effects of plastic mulch debris on the structure of plant soil and root growth have been fully studied, but their effects on endophytic microbial communities have not been explored to a large extent. Methods: In this study, High-throughput sequencing of bacterial 16S rRNA genes and fungal ITS region sequences were used to analyze microbial community structure and composition in rhizosphere soil and root endophytic of tea plant under three different weeding methods: polyethylene mulching, hand weeding and no weeding (CK). Results: The results showed that the weeding methods had no significant effect on the rhizosphere and root endophytic microbial abundance, but the rhizosphere bacterial structure covered by polyethylene mulch was significantly different than hand weeding and CK. The rhizosphere fungal diversity was also significantly higher than the other two analyzed treatments. The community abundance of rhizosphere microorganisms Acidobacteria, Candidatus Rokubacteria and Aspergillus covered by polyethylene mulch decreased significantly, whereas Bradyrhizobium, Solirubrobacterales and Alphaproteobacteria increased significantly. The abundance of bacteria Ktedonobacter, Reticulibacter, Ktedonosporobacter and Dictyobacter communities covered by polyethylene mulch was significantly changed, and the abundance of Fusarium and Nitrobacteraceae was significantly increased. Rhizosphere dominant bacteria were negatively correlated with soil available nitrogen content, while dominant fungi were significantly correlated with soil pH, total nitrogen and total potassium. Discussion: Polyethylene mulch forms an independent micro-ecological environment. At the same time, the soil nutrient environment was enriched by affecting the nitrogen cycle, and the composition of microbial community was affected. This study elucidated the effects of polyethylene mulch on soil microbial community in tea garden and provided a new theoretical understanding for weed management. [ABSTRACT FROM AUTHOR]

When a drone performs physical maneuvers in close proximity to ground objects at extremely low altitudes, the downwash generated significantly impacts the object directly beneath it. In response to this issue, we propose a drone designed to operate at low altitudes while simultaneously creating a windless zone directly beneath the aircraft, thus mitigating its impact on objects below. This entails the development of an H-shaped airframe structure capable of establishing a windless space through the manipulation of rotor angles. Our objective is to formulate a control model for the drone and implement stabilization control. The downwash characteristics of the proposed drone will be methodically investigated through experiments employing a unique 3D airflow measurement system and an operational drone. Visualization of downwash will be generated from the collected wind velocity data, showcasing the potential to create a windless zone when the rotor angle is set to 30° or higher. Additionally, in formulating the control model, we will conduct an extensive search for control parameters that contribute to stabilizing the drone during flight. Through simulation experiments, we aim to demonstrate the feasibility of controlling the drone with rotor angles up to 40° using a conventional controller, utilizing the capabilities of the parameter search algorithm.

More than 40% of the total oil palm area in Indonesia is owned and managed by smallholders. For large plantations, guidelines are available on so-called ‘best management practices’, which should give superior yields at acceptable costs when followed carefully. We tested a subset of such practices in a sample of smallholder plantations, aiming to increase yields and profitability. We implemented improved practices (weeding, pruning, harvesting, and fertiliser application) in 14 smallholder plantations of 13–15 years after planting in Jambi province (Sumatra) and in West-Kalimantan province (Kalimantan) for a duration of 3 to 3.5 years. During this period, we recorded yields, measured palm leaf parameters and analysed leaf nutrient contents. Yield recording then continued for an additional two years. In the treatment plots, the yields did not increase significantly, but the size of the bunches and the size of the palm leaves increased significantly and substantially. The tissue nutrient concentrations also increased significantly, although after three years, the potassium concentrations in the rachis were still below the critical value. Because of the absence of yield increase and the additional costs for fertiliser inputs, the net profit of implementing better management practices was negative, and ‘business as usual’ was justified financially. Some practices, such as harvesting at 10-day intervals and the weeding of circles and paths, were received positively by those farmers who could implement them autonomously, and were applied beyond the experiment. It is challenging to find and implement intensification options that are both sustainable and profitable, that have a substantial impact on yield, and that fit in the smallholders’ realities. On-farm experimentation and data collection are essential for achieving sustainable intensification in smallholder oil palm plantations.

With the increasing environmental awareness and the demand for sustainable agriculture, herbicide reduction has become an important goal. Accurate and efficient weed detection in soybean fields is the key to test the effectiveness of herbicide application, but current technologies and methods still have some problems in terms of accuracy and efficiency, such as relying on manual detection and poor adaptability to some complex environments. Therefore, in this study, weeding experiments in soybean fields with reduced herbicide application, including four levels, were carried out, and an unmanned aerial vehicle (UAV) was utilized to obtain field images. We proposed a weed detection model—YOLOv7-FWeed—based on improved YOLOv7, adopted F-ReLU as the activation function of the convolution module, and added the MaxPool multihead self-attention (M-MHSA) module to enhance the recognition accuracy of weeds. We continuously monitored changes in soybean leaf area and dry matter weight after herbicide reduction as a reflection of soybean growth at optimal herbicide application levels. The results showed that the herbicide application level of electrostatic spraying + 10% reduction could be used for weeding in soybean fields, and YOLOv7-FWeed was higher than YOLOv7 and YOLOv7-enhanced in all the evaluation indexes. The precision of the model was 0.9496, the recall was 0.9125, the F1 was 0.9307, and the mAP was 0.9662. The results of continuous monitoring of soybean leaf area and dry matter weight showed that herbicide reduction could effectively control weed growth and would not hinder soybean growth. This study can provide a more accurate, efficient, and intelligent solution for weed detection in soybean fields, thus promoting herbicide reduction and providing guidance for exploring efficient herbicide application techniques. [ABSTRACT FROM AUTHOR]

This paper aims to shed light on the state of the Reference Collection in post-secondary Art and Design libraries. Recent trends indicate that the availability of electronic research tools is a factor in institutions dismantling their print collections; however, others have argued for retaining them for their convenience, low cost, and even for their value as training tools. This research seeks to determine what types of reference collections art and design libraries are maintaining, how they are using and promoting them, and what considerations go into their removal. [ABSTRACT FROM AUTHOR]

To determine the difference in greenhouse gas emissions between two rice (Oryza sativa L.) varieties; Takanari (Tak) and Koshihikari (Kos), under organic rice cultivation with or without weeds management, a pot experiment was conducted at Tsuruoka, Yamagata, Japan. The Tak and Kos varieties were transplanted individually and interplanted as Tak+Kos, with the main treatments of weeding (w) and no-weeding (nw). Methane (CH4), nitrous oxide (N2O), and plant night respiration (CO2 emission) fluxes were measured once weekly or biweekly during the rice growth period. As the results, N2O fluxes were not detected but CH4 fluxes varied with the rice growth stage for all treatments. Compared with the Kos(w), Tak(w) and Tak+Kos(w) significantly decreased total seasonal CH4 emissions by 12.4% and 19.1%, respectively. This was attributed to higher rhizospheric CH4 oxidation and the offset of potential methanogenic activities because of the larger root biomass and a higher harvest index for both Tak(w) and Tak+Kos(w) compared with Kos(w). Conversely, Kos(nw) significantly reduced cumulative CH4 emissions by 31.7% and 48.6% compared with Tak(nw) and Tak+Kos(nw), respectively. This was ascribed to high rhizospheric CH4 oxidation promoted by the presence of significantly higher weed biomass for Kos(nw) at 65.0% and 44.0% compared with Tak(nw) and Tak+Kos(nw), respectively. On average, the no-weeding practice significantly decreased cumulative CH4 emissions by 50.5% compared with the weeding practice, with a significantly high (P<0.001) interaction between weed management and variety differences observed. The CH4 emissions and plant biomass under variety interplanting (Tak+Kos) were not significantly different to Tak individual planting, but were significantly different to Kos individual planting, which implied variety Tak had strong competition to variety Kos. More studies on appropriate variety choice and pairs, and the effect of aquatic weeds presence in no-weeding organic paddy fields are necessary to estimate CH4 emission and attenuation. [ABSTRACT FROM AUTHOR]

Deselection and removal of materials (a.k.a. weeding) and gift acquisition of materials (a.k.a. gift books) are two essential practices for librarianship, yet may not be as routine as other aspects of collection development. These practices often become special projects that require more effort and time than routine practices. In June of 2022, the Christopher Center Library Technical Services Department opted to transition from special project weeding and sporadic gift acquisition to an alternating schedule of deselection and gift acquisition. Due to personnel changes and a smaller workforce within the library, creating a routine practice for collection management was not only best practice, but also was necessary to prevent burnout and bottlenecks within workflows. This article will reflect the first 12 months of the newly developed and implemented policy and explore the successes, obstacles and best practices for libraries interested in routine collection management. [ABSTRACT FROM AUTHOR]

Between 2017 and 2019, I created three temporary artistic interventions in public spaces in which passers-by could discover, interact with or ignore different materials related to libraries as social, public systems. During my work with the first, Expired Outdoors (2017), serendipity emerged as a principle I became interested in exploring further. In two consecutive installations, serendipity gradually manifested itself both as an interface between my installations and their audience and as a creative strategy guiding my choices of contexts and materials. Upon invitation from editor Olga Schmedling, in this article I discuss aspects of serendipity in the three projects, proposing to understand serendipity as instances of interruption rather than as accidental discovery.

In Hokkaido, northern Japan, bareroot Sakhalin fir seedlings are conventionally planted in spring and fall, following strip site preparation that alternates managed and unmanaged strips. However, this method requires seven years of weeding due to encroachment of evergreen dwarf bamboo. Given diminishing forest labor availability, a shortage of workers for planting and weeding operations has become a problem in reforestation following clearcutting. We examined whether comprehensive mechanical site preparation (MSP) could reduce weeding frequency by preventing regrowth of dwarf bamboo and whether container seedlings could extend the planting season into summer. Over eight years, the survival and growth of summer-planted bareroot and container seedlings were examined on a fully MSP-treated site with only one weeding operation in the fifth year. Full-site MSP resulted in a shift of the vegetation from dwarf bamboo to deciduous plants, leading to high survival and growth rates of Sakhalin fir seedlings despite minimal weeding. Container seedlings exhibited superior establishment and maintained higher survival rates over eight years than bareroot seedlings. However, planting on the forwarder trail decreased seedling growth, and ultimately decreased survival under rare summer drought. Our findings indicate that container seedling summer planting and full-site MSP may represent an alternative approach to reforestation of Sakhalin fir, potentially reducing the need for weeding and extending the planting season.

The rice cultivation systems commonly used by farmers are the transplanted (called ‘Tapin’) and the direct-seeded (called ‘Tabela’) system. The Tabela system has many advantages over the Tapin system but has a weakness: the increase in weed population due to water conditions during transplantation. Therefore, weed management is necessary to increase rice yields. One way to control weeds is by applying herbicides. Using a single active ingredient herbicide continuously increases the chances for weeds to develop resistance against these active ingredients. Therefore, mixing herbicides with different active ingredients can be an alternative to improve weed management. This study aims to determine the effect of weed control and cropping systems to suppress weeds and provide the highest growth and rice yield. The research was conducted at the Agricultural Training and Development Research Center (Sanggar Penelitian Latihan dan Pengembangan Pertanian [SPLPP]) of the Faculty of Agriculture, Universitas Padjadjaran, Ciparay, Bandung Regency. This research was designed as a separate plot design with ten treatments and three replications with the main plot of cropping system and subplots of weed control. Weed management treatments consisted of bensulfuron-methyl 12% and bispyribac-sodium 18%; penoxsulam 15 g/L and pretilachlor 385 g/L; cyhalofop-butyl 100 g/L; manual weeding; and untreated control. Results that showed significant differences were tested using Duncan's test (DMRT) with α = 5%. Results showed that the Tabela system combined with bensulfuron-methyl 12% and bispyribac-sodium 18% suppressed weed growth and provided good growth and rice yield.

This Interactive Web column focuses on a traditional aspect of library management – deselection and weeding of physical materials. It describes the process and considerations of a traditionally conservative library when evaluating Open Access journal availability as a suitable substation for retained print materials. While many, if not most, medical and hospital libraries have weeded a significant part of their older print collections, it is still common to have both older print serials holdings and a pressing need for space. [ABSTRACT FROM AUTHOR]

Clear-cutting and weeding of riparian habitats in peri-urban watercourses are common practices that may lead to a lower cover and to changes in vegetation assemblages, encompassing increments in the proportion of exotic and ruderal species. The aim of this work was to study the herbaceous assemblages prior to and along three years after deforestation in the Lujan's River riverbank, which was dominated by the invasive species Gleditsia triacanthos and other woody exotics. Four sites were sampled, on one occasion before and five times after the disturbance, assessing at each site the percentage of bare soil and the cover by species. After deforestation, the proportion of bare soil became significantly lower from 15 months on. Before the disturbance the species richness was 21, and two years later it stabilized in more than 50 species, while beta diversity remained mostly unchanged. The assemblages found before and on the first sampling after the disturbance were the most different between all pairs (ANOSIM, SIMPER). Both exotic as ruderal species increased in the first stages, and then returned to pre disturbance values. Three years after deforestation, the changes in diversity suggest that a different assemblage has established in place of the pre disturbance one. The resulting assemblage has higher cover and number of species and is co dominated by both riparian native species and disturbed environments species, while the proportion of exotic and ruderal species remains unchanged. [ABSTRACT FROM AUTHOR]

Competition between planted seedlings and vegetation is a critical constraint affecting the survival and growth of seedlings at the initial stages of forestation. Quantitatively assessing the impact of competitive vegetation on the growth of planted seedling is vital for reduction of weeding cost. This study compared the survival and growth of potentially fast-growing hybrid larch F1 seedling (Larix gmelinii var. japonica × L. kaempferi) with Japanese larch (L. kaempferi) at three competitive levels, which were 0–50%, 50–75% and 75–100% of the seedling surface covered by vegetation after planting. When more than three-quarters of the seedling surface was covered by vegetation, the survival rate of Japanese larch dropped substantially. In contrast, hybrid larch F1 sustained a high survival of 95% despite the high covering. Annual height growth significantly decreased with increasing coverage for both species. In addition, the height growth of hybrid larch F1 was significantly higher than that of Japanese larch, whereas the difference became insignificant when more than three-quarters of the surface was covered. If the requirement for weeding is whether three-quarters of the seedling surface is covered or not with vegetation, it was determined that hybrid larch F1 did not require weeding if the seedling height attained about 170 cm in the previous fall; whereas Japanese larch needed about 200 cm. The findings imply that weeding is needed to unlock the hybrid larch F1's high growth potential, and that weeding can be accomplished more than a year earlier than with Japanese larch. [ABSTRACT FROM AUTHOR]

Corn's multi-functionality as food, animal feed, and industrial raw material contributes to food security. Due to the infestation of the cob borer, maize yield frequently decreases. There have been reports of Helicoverpa armigera Hubner causing crop losses globally. The implementation of an integrated pest management (IPM) strategy employs an ecological IPM concept, one of which is the development of healthy plants employing fertilizer and weeding. This study was conducted to assess the impact of fertilizer and weeding on corn cob borer (H. armigera Hubner). The study technique employed was a factorial randomized block design (RAK) with two variables. The first component, fertilization, had three levels: P0 (no fertilizer), P1 (Papua Nutrient fertilizer), and P2 (NPK fertilizer). The second aspect is weeding, which has three levels: G0 (daily weeding), G1 (weeding every 4 days), and G2 (8 days interval weeding). The results indicated that the interaction between fertilization and weeding had no significant impact on any of the observational variables. The effect of NPK fertilization on the weight parameters of fresh corn cobs with and without cobs was considerable. [ABSTRACT FROM AUTHOR]

Many libraries face the challenge to deal with the often massive but very little used print collection. At the Vrije Universiteit Amsterdam (VU), the library started the three-year project Re:Booking to repurpose the print collection in new and innovative ways in close collaboration with communities throughout the university. In this practice paper, we outline our unusual approaches and present the results from the first two years of the project. With our paper, we hope to inspire other libraries to take a fresh look at the value of their print collections.

The Cheadle Center at UCSB manages the North Campus Open Space (NCOS), which is a project that has restored 136 acres of upland and wetland habitats that existed before the area was converted into the Ocean Meadows Golf Course in the 1960s. The NCOS restoration project began in 2017 with a fine-scale grading of the site in order to recreate the salt marsh and use the excavated soil to rebuild the upland habitats to the southwest, which are now called the NCOS Mesa. In addition to re-establishing native biodiversity, a key goal of the restoration is to utilize the site as an educational, scientific, and recreational resource. This archived version of the September 2019 newsletter includes updates on weedwhacking to promote plant diversity and new mesa slope plantings. The feature story focuses on water quality monitoring results. Community photos include Red-Tailed Hawk (Buteo jamaicensis) and egrets.

The Cheadle Center at UCSB manages the North Campus Open Space (NCOS), which is a project that has restored 136 acres of upland and wetland habitats that existed before the area was converted into the Ocean Meadows Golf Course in the 1960s. The NCOS restoration project began in 2017 with a fine-scale grading of the site in order to recreate the salt marsh and use the excavated soil to rebuild the upland habitats to the southwest, which are now called the NCOS Mesa. In addition to re-establishing native biodiversity, a key goal of the restoration is to utilize the site as an educational, scientific, and recreational resource. This archived version of the June 2019 newsletter includes updates on Western Snowy Plovers (Charadrius nivosus) breeding and cumulative totals of work hours and area planted. The feature story highlights some of the student workers reflecting on their experiences at NCOS. Community photos include Painted Lady butterfly (Vanessa cardui), Mallard (Anas platyrynchos), and Canada Goose (Branta canadensis).

The Cheadle Center at UCSB manages the North Campus Open Space (NCOS), which is a project that has restored 136 acres of upland and wetland habitats that existed before the area was converted into the Ocean Meadows Golf Course in the 1960s. The NCOS restoration project began in 2017 with a fine-scale grading of the site in order to recreate the salt marsh and use the excavated soil to rebuild the upland habitats to the southwest, which are now called the NCOS Mesa. In addition to re-establishing native biodiversity, a key goal of the restoration is to utilize the site as an educational, scientific, and recreational resource. This archived version of the March 2019 newsletter includes updates on the NCOS user survey, beach wrack brought into NCOS by tides, trail refinement, and the spring breeding and nesting season. The feature story focuses on spring planting and weeding plans on the NCOS Mesa and other parts of the site. Community photos include California Saltbush (Extriplex californica), Blue-eyed Grass (Sisyrinchium bellum), hooded mergansers (Lophodytes cucullatus), and a loggerhead shrike (Lanius ludovicianus).

IntroductionPotato is one of the most valuable food products. Indeed, no product has the capacity to produce energy per unit area compared with it. Potato has been an important part of the diet in most countries, especially in developing countries. Conventional cropping systems emphasize short-term goals such as high profitability and yield, and their maintenance costs are maximized due to the use of external inputs such as fertilizers and chemical pesticides, so with no use of external inputs, yield is greatly reduced. On the other hand, sustainable farming systems are systems that rely on low-energy inputs and small amounts of chemicals for long-term production stability and environmental adaptation. The purpose of this study was to investigate the effect of different cropping system management on yield, yield components and weed diversity in potato cultivation.Materials and MethodsThis experiment was conducted during the two years of 2015-2016 and 2016-2017 in the farm of Ran-Firoozkooh Cooperation Ltd., located at 10 km east of city of Firoozkooh city. The experiment was conducted as split plot arrangement based on a randomized complete block design with four replications. In this research, various agricultural management assigned to the main plots and weeding and no-weeding operations were allocated to the sub plots. Cropping systems include the high input, medium input, low input and ecological. At the early June, the potato seed tubers were planted in plots of 15 × 6 m (with a distance of 70 cm between the rows, 22 cm on the rows) in all cropping systems. At the end of the growing season (Oct, 1) potato tubers were harvested. Data were analyzed using SAS 9.1 and figures were prepared using MS-EXCEL software.Results and DiscussionMean comparisons showed that the highest single tuber weight (87.6 g) obtained from high input system, which was 26% higher than the low input system. The results also indicated that the weight of single tuber was increased with increasing weed control, so that the highest rate of this trait was obtained from weeding treatments. In the ecological system, the yield of the tuber in the weed control treatment was significantly different than the weedy treatment. The highest amount of tuber yield was resulted in the high input system and in weeding treatment which was significantly higher than the ecological system and the weedy treatment. In the high input system, more access to nutrients (NPK) resulting in improved yield and growth component. The phosphorus used in the high input system has different roles such as cell division, fertilization and development of reproductive organs. This can improve root and tuber development and increase water absorption and nutritional elements. Another reason for the increased yield in medium and high-input cropping systems could be assigned to the reduction of weed density in these systems. Means comparison showed that the nitrogen content of tuber in the high input system was 1.34%, which was higher than the low input system by 13%. The highest level of this trait was obtained in weeding. Plants grown in the high-input system stored more of nitrogen in their tissues due to the higher input of nitrogen fertilizer. Dzida and Jarosz (2006) reported that in a greenhouse experiment, the application of nitrogen fertilizer had a positive effect on nitrogen accumulation in the shoots of savory (Satureja hortensis). On the other hand, Derakhshan et al. (2018) stated that increasing nitrogen fertilizer is not only not beneficial to the crop, but also complicates the weed problem, in which case weeds absorb nutrients faster and more than the crop. There was a negative correlation between increasing the use of inputs and Shannon-Wiener index, so that ecological system (1.32), which was without the use of inputs, had the highest rate of this index and the lowest one was observed in the high input system (0.87). The main reason for the loss of biodiversity in conventional farms compared with low and ecological systems seems to be the intensification of agricultural operations, which is associated with excessive consumption of inputs, including herbicides.ConclusionIn general, the results of this study showed that with increasing input, yield and yield components of potatoes increased. The results also showed that the highest amount of nitrogen was observed in tubers, potato shoots and also in weed tissues in the high input system and therefore it can be suggested that more use of chemical fertilizers has resulted in more nitrogen storage in different plant tissues. On the other hand, with the decrease in the input in ecological and low-input systems, the amount of Shannon-Wiener diversity index increased so that the highest amount of this index was observed in ecological and low-input systems. Considering the reduction of environmental pollution in ecological systems, it seems that such systems are environmentally friendly and if such services can be valued, the ecological system will be more superior compared with the conventional ones.

The present study aims to investigate the process of collection development in the library of Institut Teknologi Indonesia. The researcher applies the six stages of collection development from Evans (2005) as the theoretical framework. The research method used in the study includes descritive analysis using the data, from interviews from its librarians, questionnaire and the additional observation to make the data more accurate. The result reveals that the library of Institut Teknologi Indonesia makes the most of community analysis, selection process, and the weeding process for the collection development activities. Yet, the library needs more efforts in making the policy and evaluation activity. Surprisingly, after comparing with other university libraries, it is found that those libraries do not have formal and systematic policies of collection development, and they also barely conduct the evaluation meetings after the collection development activity is completed. The contribution from the stakeholders and incumbents are needed to escalate the collection development in the library.

Nowadays the explosion of information sources has shaped how library users access information and provide feedback on their preferences. Therefore, faced with this explosion and the blossoming of digital libraries, modern libraries must take up the challenge of meeting the needs of their users and considering their opinions and preferences in order to offer them adequate resources and henceforth eliminate those that are unsatisfactory.Almost all library recommender systems aim to provide users with items of interest to them. However, despite its definite interest, the staff-oriented adaptation and application of this revolutionary technique to the collection development process is still in an embryonic stage.We propose a patron-driven hybrid library recommender system that uses machine learning techniques to recommend and assist in the acquisition and weeding decision-making operations by extracting and analyzing users’ opinions and ratings. The recommender system is applied and validated in a real national library case using Amazon’s digital library and the library’s catalog as a data source.

Weeds are located in the seedling line zone area near the root zone of rice. It is inevitable for the weeds to compete with the rice for the water and nutrients, leading to the reduction of rice yield and quality. An accurate assessment of weed density can greatly contribute to the weed control and ecological benefits. However, the commonly-used visual perceptions cannot assess the weed density under the background disturbance and leaf shading of rice plants. In this study, a novel tactile perception was proposed to accurately evaluate the weed density grade in the seedling line zone of the paddy fields. Firstly, the polyvinylidene fluoride (PVDF) sensor was wrapped with a mixture of two properties of liquid silica gel. A tactile sensor was then obtained to produce the voltage changes after solidification using micro deformation. As such, the tactile sensor was also applied to evaluate the weed density in the seedling line zone. Secondly, an accurate extraction was performed on the joint features in the time domain and mel-frequency cepstral coefficients in the tactile data. The joint features were then input into the principal component analysis. The optimal feature dimensions were determined to construct the feature vector of weed density assessment. A comparison of multiple models was conducted to optimize the classification and assessment of the weed density model. Classical machine learning models were selected, such as the support vector machines (SVM) with the high generalization capability, K-nearest neighbors for classification and regression, random forests (RF) with the a high resistance to overfitting, and neural networks (NN) to implement the complex learning tasks. More importantly, the newly developed random subspace K-nearest neighbor model was selected using multi-classifier fusion and Random Sparse Sampling Ensemble Learning model with the adaptive balancing sample class function of random under-sampling integrated learning models. The training set, validation set, and test set were randomly selected during this time. The average value was taken as the accuracy of weed density level after assessment. Finally, a weed density level assessment model was constructed using the NN. The effectiveness of the joint features was also verified to extract from the tactile signals, and then to compare the accuracy of the assessment of different models. The best feature dimensions of the different models were selected to compare the assessment accuracy of weed density levels in the different dimensions. Furthermore, the tactile sensor speed and contact height were selected to verify the accuracy and stability of weed density assessment. As such, the experimental factors were taken as the most influence on the assessment. Meanwhile, the regulation was clarified for the effect of tactile sensor speed and contact height on the performance of weed density assessment after experiments. Specifically, the barnyard grass seeds were randomly scattered by hand within 5 days of rice transplanting, according to the natural growth pattern of rice and grass in the transplanted rice fields. The experimental results showed that the artificial NN model was provided the best evaluation accuracy using the optimal feature dimension. Once the tactile sensor was in the low contact mode with the stalk, the accuracy and stability of weed density assessment decreased as the paddy machine travel speed increased. When the tactile sensor was in the high contact mode with the leaf canopy, the weed density assessment accuracy increased and stability decreased, as the paddy machine travel speed increased. Consequently, the best overall performance was found at the travel speed was 0.5 m/s under the low stalk contact. The accuracy of weed density assessment was 85.33% at this time. The coefficient of variation was 2.73% for the accuracy of weed density assessment. A systematic optimization can be expected to determine the weed control operation mode and application system parameters, in order to further investigate the weed data set expansion and tactile feature extraction. The finding can also provide a more practical for the quantitative application and decision making. [ABSTRACT FROM AUTHOR]

Drone images from an experimental field cropped with sugar beet with a high diffusion of weeds taken from different flying altitudes were used to develop and test a machine learning method for vegetation patch identification. Georeferenced images were combined with a hue-based preprocessing analysis, digital transformation by an image embedder, and evaluation by supervised learning. Specifically, six of the most common machine learning algorithms were applied (i.e., logistic regression, k-nearest neighbors, decision tree, random forest, neural network, and support-vector machine). The proposed method was able to precisely recognize crops and weeds throughout a wide cultivation field, training from single partial images. The information has been designed to be easily integrated into autonomous weed management systems with the aim of reducing the use of water, nutrients, and herbicides for precision agriculture. [ABSTRACT FROM AUTHOR]

The rice cultivation systems commonly used by farmers are the transplanted (called 'Tapin') and the directseeded (called 'Tabela') system. The Tabela system has many advantages over the Tapin system but has a weakness: the increase in weed population due to water conditions during transplantation. Therefore, weed management is necessary to increase rice yields. One way to control weeds is by applying herbicides. Using a single active ingredient herbicide continuously increases the chances for weeds to develop resistance against these active ingredients. Therefore, mixing herbicides with different active ingredients can be an alternative to improve weed management. This study aims to determine the effect of weed control and cropping systems to suppress weeds and provide the highest growth and rice yield. The research was conducted at the Agricultural Training and Development Research Center (Sanggar Penelitian Latihan dan Pengembangan Pertanian [SPLPP]) of the Faculty of Agriculture, Universitas Padjadjaran, Ciparay, Bandung Regency. This research was designed as a separate plot design with ten treatments and three replications with the main plot of cropping system and subplots of weed control. Weed management treatments consisted of bensulfuron-methyl 12% and bispyribac-sodium 18%; penoxsulam 15 g/L and pretilachlor 385 g/L; cyhalofop-butyl 100 g/L; manual weeding; and untreated control. Results that showed significant differences were tested using Duncan's test (DMRT) with R = 5%. Results showed that the Tabela system combined with bensulfuron-methyl 12% and bispyribac-sodium 18% suppressed weed growth and provided good growth and rice yield. [ABSTRACT FROM AUTHOR]

In recent years, machine vision systems (MVS) with convolutional neural networks (CNN) for precision spraying have been increasingly investigated due to their robust performance in plant detection. However, the high computational requirement of CNNs makes them slow to be adopted in field operations, especially in unstructured working environments such as broadcast-seeded fields. In this study, we developed a modular precision sprayer by distributing the high computational load of CNN among parallel low-cost and low-power vision computing devices. The sprayer utilized a custom precision spraying algorithm based on SSD-MobileNetV1 running on a Jetson Nano 4 GB. The model achieved 76% mAP 0.5 at 19 fps for weed and soybean detection in a broadcast-seeded field. Further, the sprayer targeted all weed samples and exhibited up to 48.89% spray volume reduction with a typical walking speed up to 3.0 km/h, which was three times faster than similar systems with known targeting performance. With these results, the study demonstrated that CNN-based precision spraying in a complex broadcast-seeded field can achieve increased velocity at high accuracy without needing powerful and expensive computational hardware using modular designs. [ABSTRACT FROM AUTHOR]

Background and aims: Competitive vegetation in forest stands influence seedling growth by changing soil nutrient availability. However, studies on the effects of different weed control methods on seedling growth of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) are rare. Methods: We applied three weed control methods, comprising artificial sickle weeding (ASW), woody disc weeding (WDW), and nonwoven cloth weeding (nWCW), to explore their effect on growth of Chinese fir seedlings in a plantation in Jiangxi Province, China. Results: The weed control methods affected the shoot height and root-collar diameter of the seedlings. The contents of sugar, glucose, triglycerides, total cholesterol, and free fatty acids in newly developed leaves were increased after ASW and nWCW treatment, and were consistent with the expression of genes associated with glucokinase, sucrose phosphate synthase, and sucrose synthase. Weeding method influenced soil properties, including pH, moisture, total nitrogen (TN), ammonium-N, nitrate-N, total phosphorus, available phosphorus, and dissolved organic carbon contents. Moisture content was the main factor that influenced the soil bacterial community and leaf nutrition. High-throughput sequencing of the bacterial 16 S rRNA gene revealed that the weeding methods affected bacterial community structure. Specifically, compared with ASW and nWCW, WDW contributed to lower soil bacterial diversity, simpler bacterial interaction, and increase in pathogenic bacteria potential. Conclusions: The weeding methods differ in influence on soil bacterial community structure, soil properties, and plant growth, which are potentially useful to improve the growth of Chinese fir seedlings. ASW and nWCW strategies were recommended to be applied in the practice of weed control on seedling growth of Chinese fir. [ABSTRACT FROM AUTHOR]

The investigation was carried out during the period 2015 - 2016 at the experimental field of the Maize research institute – Knezha on typical chernozem. The following variants were included in the experiment: Zero control K0 – without treatment, weed infested in natural background, control without herbicides K1 – economical with two manual weedings, without weeds, Merlin 750 VG– 12.5 g/da, - 200 ml/ da, Ekip SK - 250 ml/da, Bazis 75 DF - 2.5 g/da. The tested herbicides showed a high selectivity to maize. Herbicide Merlin 480 SK (izoxaflutol) – 12.5 g/da applied after sowing, before crop emergence and Ekip SK (foramsulfuron, antidote) in doses 200 ml/da and 250 ml/da, inserted 4-5 plant leaf, shown a good herbicide effect. In the conditions of the field experiment, the studied preparations destroyed from 56.09 to 65.96% of the weeds, which averted the initial weed infestation at the experimental plots. A very good effect against johnson grass was reported after treatment with Bazis 57DF (rimsulfuron + thifensulfuron), which destroys up to 96% of the johnson grass from seeds and up to 90% of the johnson from rhizomes. [ABSTRACT FROM AUTHOR]

Background and Objective: This study was conducted to investigate the combined use of duck in different rice cultivation systems on growth indices, photosynthesis and water productivity of fields.Materials and Methods: The experiment was carried out as a split plot factorial experiment based on randomized complete block design with three replications in Research Farm, Faculty of Agricultural Sciences, University of Guilan, in 2017 and 2018 years. Treatments included of three levels of cultivation system; Conventional Cultivation (CC), Improved Cultivation (IC) and SRI (System of Rice Intensification) as the main factor and combined of two levels of duck (control and 750 duck per hectare) and three levels of weed control (control, once and twice weeding) factorials as a sub-factor.Results: The results showed that the beginning of the growing period, all experiment treatments showed a significant difference in terms of leaf area index and with increasing the length of the growing period; the increase in leaf area index was greater in terms of combine treatments of 750 ducks per hectare and SRI. At the beginning of growth, CGR in SRI system was slower than the others and in the middle to late growth period, CGR rate values were in SRI>IC>CC. In un-use duck conditions, Conclusion: In general, the combined application of rice-duck in different cultivation systems can be considered suitable for improving the quantitative yield and growth and physiological indicators of rice to achieve sustainable agricultural goals and increase farmers' income per unit area in the plain areas of Guilan.

Robot simulation is an important way to verify the correctness of model and feasibility of design. Taking the Delta parallel mechanism as the effector of a weeding robot, this paper designs the workspace for the weeding mechanism in the field of corn seedlings, when each corn seedling has three to five leaves, and then carries out a simulation analysis on the workspace of the weeding mechanism. To realize variable rate precision spraying, the authors planned a three-segment gate-shaped trajectory for the end effector, detailed the trajectory under the joint coordinate system, and analyzed the motion law of S-curve motion profile. Then, the law of each kinematics parameter was solved on MATLAB, and plotted into graphs. Based on the simulation results, a prototype was developed for the proposed weeding mechanism, and subject to weeding experiments to obtain the end effector trajectory. Compared with the simulated results, the maximum deviation in the end effector trajectory during actual operation was 11.58%; the prototype could complete a weeding action every 2.8 s, while advancing at the speed of 0.4 m/s. The results fully demonstrate the feasibility of applying Delta parallel mechanism in weeding, and the reasonability of our workspace design and trajectory planning.

High quality standards in vegetables is one of the most important expectation of consumers presence of weeds would also reduce the quantity and quality of crops produced. Use of cover crops could be an environmentally friendly alternative to conventional chemical and mechanical methods. To this end for controlling weeds, a factorial experiment based on a randomized complete block was conducted at the Research Farm of Mohaghegh Ardabili University with three replications in 2017. Experimental treatments were the first factor, consisting of mono culture and intercropping of rye (Secale cereal L.), hairy vetch (Vicia villosa Roth.) and control treatment (no cover crop) and the second factor consisting of one time hand weeding and two times weeding, with 15 days intervals, and without hand weeding, as control. The results showed that the highest dry biomass of cover crops obtained from rye mono culture (530.59 g.m-2) and the lowest biomass (47.85 g.m-2) from hairy vetch mono culture. The highest reduction of total weed biomass (83.24%) obtained from rye with hairy vetch without hand weeding. The highest yield of iceberg lettuce was obtained from hairy vetch mono culture with one-time hand weeding or from without hand weeding treatment (5025 and 4965 g.m-2, respectively). Also, the highest plant height, number of leaves and diameter of lettuce stem was not statistically significant difference from mono culture and intercropping of cover crops. The results showed that the combination of hand weeding and cover crop residues were more effective in controlling and reducing weed biomass, but the presence of cover crop residues in the shortron also increased the yield of iceberg lettuce through weed control.

Forest restoration is challenging in arid and semiarid lands. Research has identified ecotechnologies that may alleviate stressful conditions of planted seedlings, but studies are often limited to the first few years of regeneration establishment. Over 20 years, we tested the effects of tree shelters (mesh- and tube-shelters) and competition suppression (two types of synthetic mulch and manual weeding) on soil water content and development of Pinus halepensis on an arid site in southeastern Spain. Competition suppression increased soil water content at shallow depths only using a polyethylene sheet, with no effect on survival. Tree shelters had a much greater effect than competition suppression on tree responses. Survival was mostly affected by shelter type, with lower survival in tube-shelters compared to mesh-shelters and non-protected seedlings; differences began after the first year, but became more pronounced following an intense drought at 3 years. Survival for pines protected by mesh-shelters was significantly higher than for non-protected seedlings beginning at 6 years, and mortality did not stabilize until 15 years. After 20 years, survival ranked in order of mesh-shelters (57.5%), non-sheltered (46%), and tube-shelters (29.5%). Effects of shelter type on growth response over time followed an opposite pattern, with differences declining when pines outgrew the height of the shelter after 3 years. The response of pines to tube-shelters could be explained by the microenvironmal differences among vertical protection and its effects on a shade intolerant species such as Pinus halepensis: survival depletion is provoked probably by a reduction in root growth under the shaded conditions of tubes. On the other side, growth and morphology response could be partially explained by differences in light, but response of pines in mesh also points towards a reduction of wind pressure that precludes stem growth in thickness. Competition suppression had no effect on pine growth. Lack of response to main effects of competition suppression treatments can be attributed to the minimum changes of soil water content to mulching or weeding under arid conditions. Thus, 20 years after planting, tube-shelters and competition suppression treatments were relatively ineffective at improving survival or growth of P. halepensis. Mesh-shelters are recommended as the most effective protection method for restoration under arid site conditions.