Net Cover Research Articles

Protective covers impact honey bee colony performance and access to outside resources

Protective crop covers are used extensively to protect high-value crops from bird and hail damage, however, these structures may present challenges for honey bees (Apis mellifera L.), the main pollinators in these systems. Some studies have indicated that protective covers result in declines in colony size and resource storage, but few replicated field trials exist. To determine the impact of protective cropping structures on honey bee brood production and resource storage, 14 honey bee colonies were placed inside and outside of protective covers on four blueberry (Vaccinium corymbosum and V. virgatum) farms in northern New South Wales, Australia. We measured changes in brood production, pollen and honey storage, hive weight and ambient hive temperature fortnightly over a 12-week period. Brood production, pollen and honey storage, and hive weight all displayed greater reductions within four weeks of placement under net cover, compared to hives outside of net cover. Although brood and honey metrics gradually increased in all hives during the remainder of the 12-week monitoring period, hives located under protective netting had relatively smaller gains in brood production and pollen storage when compared to hives located outside the protective covering. Hives under protective netting that were in the shade and/or whose entrances were facing south were most impacted by the end of the monitoring period. Our findings highlight the need for protected crop management strategies to consider pollinator health as well as crop pollination needs so that both bee health and pollination services are maintained in these systems.

A new feature of the laboratory model plant Nicotiana benthamiana: Dead‐end trap for sustainable field pest control

Societal Impact StatementConventional pest management measures release large amounts of chemical or plastic pollutants into the environment. Nicotiana benthamiana, a commonly employed laboratory model plant, demonstrated remarkable lethality and attractiveness towards several important Hemiptera and Thysanoptera insect pests. Field trials showed that the N. benthamiana plants can be used as a dead‐end trap to successfully control these pests, comparable to commercial plastic sticky traps. Notably, the N. benthamiana in the field grew well without negatively impacting crop growth, natural enemies, and pollinators. This study unearths a new benefit of N. benthamiana and develops an easy‐to‐apply and sustainable strategy for field pest control.Summary Hemiptera and Thysanoptera insects pose persistent threats to agricultural production. Conventional management strategies involve the release of chemical or plastic agents, causing adverse environmental and global health issues. Notably, Nicotiana benthamiana, a globally utilized model plant, exhibits remarkable lethal effects and attraction towards these pests. In this study, we explored the potential of using N. benthamiana for Hemiptera and Thysanoptera pest control in the laboratory and field. Through net cover and three field assays over 2 years, we demonstrated the efficacy and benefits of using N. benthamiana as a field‐deployed pest control dead‐end trap. N. benthamiana demonstrated nearly 100% lethality to whiteflies, aphids, and thrips, with emitted volatiles attracting these insects. Field trials showed that potted and planted N. benthamiana blocks and traps whiteflies and thrips from several Solanaceae and Cucurbitaceae crops effectively, comparable to common commercial yellow and blue sticky boards. Moreover, N. benthamiana in the field exhibited robust growth in commercial greenhouses without negatively impacting crop growth, natural enemies, and pollinators. Our study introduces an innovative, easily implementable, and sustainable approach for controlling Hemiptera and Thysanoptera pests. Moreover, it unveils the novel utility of N. benthamiana in field‐based pest management.

Dynamics of land use land cover change in an East African inland valley wetland

AbstractThe dynamics of inland valley wetlands landuse landcover (LULC) changes are of ecological and economical significance hence necessitating up‐to‐date datasets of resource status. Nalwekomba inland valley wetland is highly agriculturally utilised yet ecologically important wetland threatened with conversion. Historical LULC data sets as bench marks justifying wetland conservation are lacking. Therefore, the spatial–temporal LULC changes in Nalwekomba inland valley wetland were analysed through a combination of remote sensing and GIS, using satellite images of 1990, 2000, 2010 and 2020 as reference years. Results revealed variable dominance of grassland and tree cover for the wetland and its catchment over the years; 32.7% and 35.3% and 30.9% and 29.8%, respectively, for 1990 and 41.4% and 30.4% and 26.3% and 29.1% for 2020. The 30‐year analysis revealed increasing area‐shifts for cropland and built‐up/settlement of 265.7% and 76.2%, respectively, reducing cover for shrubland by 78.31% in the wetland. Similar trend emerged for its catchment. Highest net cover gains and losses identified between 1990 and 2000 were for cropland and tree cover respectively. The observed trend points to the need for landuse planning and landcover management to enhance ecosystems' resilience to support sustainable livelihoods dependent on this ecosystem.

Legume-based cover crop mixtures can overcome trade-offs between C inputs, soil mineral N depletion and residual yield effects

Cover crops can contribute to climate change mitigation through enhanced sequestration of atmospheric carbon dioxide into soil organic carbon. Few studies, however, have estimated the total carbon (C) input to soil, i.e. derived both from plant material (shoot and root) and phyllo- and rhizodeposition. Selection of cover crop species should account for multiple objectives, such as C inputs to soil, nitrate leaching reduction and positive residual effects on the following main crop. However, trade-offs between these objectives may occur. The aim of this study was to investigate the performance of the cover crop species winter rye, hairy vetch and oilseed radish, and to assess the ability of mixtures to overcome potential trade-offs. A randomized split-plot field trial was conducted to compare cover crop treatments and a weeded control under high and low soil nitrogen (N) availability. Multiple-pulse labeling with 14C-CO2 was carried out to trace net cover crop-derived rhizodeposition C. Soil mineral N was measured to 1.5 m depth in autumn, as well as grain and N yield in the subsequent spring barley.Cover crop species accumulated between 1250 and 2580 kg C ha−1, with significantly higher total C input (in shoot, root and phyllo- and rhizodeposits) for the mixtures compared with pure stands of either vetch or radish, while the results for rye were in between. The quantity of C lost via phyllo- and rhizodeposition (qClvPR) showed a significant positive correlation with root C and was highest for the mixtures and rye. The relative ClvPR ranged between 7% and 14% of total cover crop-derived C and tended to decrease under higher soil N availability. All cover crop treatments were able to decrease soil mineral N (0–1.5 m), with radish displaying the highest N leaching reduction potential. Despite substantial differences in cover crop total N uptake and C:N ratios, no significant differences were observed in the subsequent main crop grain or N yields. The mixtures showed the highest total C input and generally a higher or similar mineral N depletion potential than the average of the pure stands, suggesting that cover crop mixtures offer a realistic means for overcoming trade-offs among ecosystem functions.

Orchard Net Covers Improve Resistance to Cherry Cracking Disorder.

Orchard net cover improves plant physiology, yield and fruit quality, pest and disease control, and anticipates fruit ripening. Moreover, this crop technology has been used to reduce natural cherry cracking (NCC). This is a serious physiological disorder that cracks the epidermis, the hypodermis, and the storage parenchyma layers of the fruit due to rainfall events near the harvest and it is related to low fruit osmotic potential and/or high fruit water permeability. This work aims to study the effect of orchard net cover on sweet cherry trees, cv. Early Bigi, in two harvesting years (2019 and 2021). The NCC, the induced cracking index (CI), and the cracking type incidence were determined. In addition, epicuticular and intra-cuticular wax content, biometric and physicochemical parameters were also evaluated. Net cover reduced the natural cracking index by 40%. High fruit weight values were observed in covered trees comparing to the control ones, with increases of 45% and 13%, in 2019 and 2021, respectively. A positive correlation was observed between CI and total soluble solids and a negative correlation between CI and wax content. Therefore, with forecasts of worsening heavy precipitation events near harvest, protecting cherry trees with nets will increase resistance to fruit cracking.

ECONOMICAL EVALUATION OF MANGO (CV. KEITT) TREES UNDER COLOURED SHADE NETS

This study explored the economical viability of five different coloured shade nets (White, yellow, red, blue and black) on mango production (Mangifera indica L. cv. Keitt). This study investigated the climatic parameters in terms of light intensity, minimum and maximum air temperature, relative humidity and plant growth across 2019 and 2020 seasons. When compared to open field conditions, coloured shade nets resulted in higher maximum temperatures and relative humidity. The black net cover and open field treatments gave the lowest mango yield compared to all greenhouse net cover. When compared to the other treatments, the use of white or yellow nets resulted in a considerable increase in the number of fruits and total yield per plant. According to prevailed conditions, it could be concluded that optimum microclimate for growing mango in similar conditions could be obtained under white and yellow nets compared to the other net covers. Black greenhouse net cover gave the lowest productivity during the experimental duration. Production costs, total revenue, net return and ratio of total revenue to cost for Keitt mango in Egypt are presented in this study. The result shows that the net return for white net reached 15777 Egyptian pound (LE) and LE 15270 per m2 in 2019 and 2020 respectively, which was 2.63 times those grown in the open field (LE 5980 and LE 5081 per 2000 m2) in 2019 and 2020 respectively. However, Revenue to cost ratio was found higher in white net in both seasons which were 1.9 and 1.8 respectively.

An Economic Analysis of Solid Waste Management in Sivagangai District

Solid waste management planning is a very critical and problematic concern of urban and semi-urban areas. The environmental problem and health hazards are the most prominent consequences of the improper of solid waste management. In Sivagangai district, door-to-door collection and segregation of the wastes are performed. The wastes are segregated either at source or at the compost yard manually. The collected wastes are transported by the tractor with a net cover. Finally, the collected wastes are disposed of in open dumpsites or in landfills. In the present study 38 Panchayats were selected from Sivagangai district which were among 2,000 selected Panchayats across the State. Environment guards in the name of Thooimai Kavalars were appointed for the implementation of the solid waste management programme in these districts. The analysis of the data on Thooimai Kavalars reveals that the appointment of Thooimai Kavalars is not proportional to the number of households in different village Panchayats. Therefore, to improve environmental cleanliness the appointment of Thooimai Kavalars should be in proportional to the number of households in the habitats. In addition, it has been observed that nearly 30% of the solid wastes generated were not cleared and stay on the street corners and temporary dump yards. To clear these wastes contribution by the generators in terms of willingness to pay is inevitable. In the study area, it has been estimated the required amount of contribution interns of willingness to pay to completely remove all the generated wastes is Rs. 300/- per annum. The yearly rate of willingness to pay this will certainly improve the employment chances not only in Sivagangai district but also nationally.

Anti-hail Net in Korla Fragrant Pear Planting

Korla fragrant pear is the main pear variety and one of the most famous fruits in Southern Xinjiang. The use of protective nets in fruit tree production is increasing; however, the cultivation of Korla fragrant pear in Xinjiang has yet to be developed. Therefore, we used the ground and underground microclimate anti-hail network and open-air conditions to determine the fruit quality and measure tree growth-related indicators. Additionally, we subsequently recorded the average yield of fragrant pear fruits to evaluate their economic value under the anti-hail net and open-air environments. Furthermore, we performed a correlation analysis to explore the correlation between environmental factors and fruit quality and growth under the two conditions. We found that the anti-hail net cover provided a conducive environment for the vegetative and reproductive growth of trees. Under similar fruit quality conditions, the average yield was markedly higher under the anti-hail net environment than under the open-air environment. Furthermore, the economic benefit under the anti-hail net was higher for all factors, except for the average facility cost during the previous year, than that under the open-air condition.

Effects of insect net coverage in field vegetables on pests, diseases, natural enemies, and yield

With the reduced availability of effective plant protection products, alternative control measures gain importance. Insect net covers are a promising tool in this regard, because they can reduce pest damage on crop by exclusion of pests. However, as under practical conditions, most crop net covers need to be removed several times during a crop cycle to manage weeds and apply fertilizers, a complete exclusion of pests is not always feasible. In addition, net covers also have an impact on natural enemies, on microclimate, and may cause direct crop damage due to their tracking weight. Therefore, effects of net applications have to be assessed accordingly, depending on the specific crops and pests. In the current paper, effects on pests, on yield, and on the occurrence of diseases are assessed in Chinese cabbage, carrot, and leek. Whereas control of Delia radicum, Phyllotreta spp. and thrips was enhanced, aphids and mining flies showed increased population build ups and caused higher damages under net cover once they had been able to invade. Some plant diseases such as Puccinia spp. and Alternaria spp. did increase under the net covers. Pitfall trap catches in carrots and Chinese cabbage were lower in almost all natural enemy groups monitored under net covers as compared to open field plots. Yield was higher with net coverage in case of Chinese cabbage and leek, but not in carrot. Results are discussed and take into account the exclusion of natural enemies and measured changes in microclimate and photosynthetically active radiation.

Practical approach for estimating flexural strengths of corroded RC members considering bond strength degradation

This study conducts parametric analyses to identify the bond strengths of corroded reinforcement by using a nonlinear model proposed in previous study, where the compressive strength of concrete (fc′), cover thickness of concrete (Cx), diameter of reinforcing bars (db), and corrosion degree (ωcorr) are chosen as key variables. On this basis, a simplified bond strength equation and corresponding flexural strength model were derived to facilitate practical applications. For verification of the proposed model, flexural test results of corroded reinforced concrete (RC) members are collected from literature, and its accuracy and applicability are affirmed by comparing the test and analysis results. According to proposed analytical model, development length required for corroded reinforcement to be yielded is less than that specified in the current design code when the ratio of net cover thickness to diameter of reinforcement (Cx/db) is greater than 4.0. While, when Cx/db is less than 1.5, it appeared that the required development length increases significantly even at low corrosion degrees less than 5%.

Mechanical damage of ‘Huangguan’ pear using different packaging under random vibration

The mechanical damage of fresh fruit under random vibration during postharvest transportation is a major problem in agricultural industry. This paper investigated the mechanical damage of ‘Huangguan’ pear (Pyrus bretschneideri Rehd. ‘Huangguan’) under random vibration excitation considering package type, vibration level, and vibration duration. Limited white noise with the frequency 3 Hz – 80 Hz was used as the excitation spectrum. Results showed: vibration results in the obvious decline of pear firmness. Firmness of pears with five package types after vibration decreased 9 % to 26 %. Package type had a great effect on the mechanical damage of pears. The package type of expanded polystyrene (EPS) tray + expandable polyethylene (EPE) net cover can provide the best cushioning effect for pears. The response vibrations of pears are related to positions. The resonant frequencies of stacked pears were concentrated in the range of 23 Hz–56 Hz. Response vibrations of pears in the corner were more severe compared with the pears in the center. In addition, the damage rules of pears with the package type of corrugated paperboard division + paper wrapping under different vibration levels and durations were revealed. The relationships of damage area and vibration level, firmness and vibration level, damage area and vibration duration conformed to linear correlation. Exponential function can be used to describe the relationships of damage volume and acceleration level, damage volume and vibration duration, firmness and vibration duration. This study provides references for vibration resistant packaging design of fruit, and thus to minimize the mechanical damage of fruit in supply chain.

Revisiting the Past: Replicability of a Historic Long-Term Vegetation Dynamics Assessment in the Era of Big Data Analytics

Open and analysis-ready data, as well as methodological and technical advancements have resulted in an unprecedented capability for observing the Earth’s land surfaces. Over 10 years ago, Landsat time series analyses were inevitably limited to a few expensive images from carefully selected acquisition dates. Yet, such a static selection may have introduced uncertainties when spatial or inter-annual variability in seasonal vegetation growth were large. As seminal pre-open-data-era papers are still heavily cited, variations of their workflows are still widely used, too. Thus, here we quantitatively assessed the level of agreement between an approach using carefully selected images and a state-of-the-art analysis that uses all available images. We reproduced a representative case study from the year 2003 that for the first time used annual Landsat time series to assess long-term vegetation dynamics in a semi-arid Mediterranean ecosystem in Crete, Greece. We replicated this assessment using all available data paired with a time series method based on land surface phenology metrics. Results differed fundamentally because the volatile timing of statically selected images relative to the phenological cycle introduced systematic uncertainty. We further applied lessons learned to arrive at a more nuanced and information-enriched vegetation dynamics description by decomposing vegetation cover into woody and herbaceous components, followed by a syndrome-based classification of change and trend parameters. This allowed for a more reliable interpretation of vegetation changes and even permitted us to disentangle certain land-use change processes with opposite trajectories in the vegetation components that were not observable when solely analyzing total vegetation cover. The long-term budget of net cover change revealed that vegetation cover of both components has increased at large and that this process was mainly driven by gradual processes. We conclude that study designs based on static image selection strategies should be critically evaluated in the light of current data availability, analytical capabilities, and with regards to the ecosystem under investigation. We recommend using all available data and taking advantage of phenology-based approaches that remove the selection bias and hence reduce uncertainties in results.

Foliar silicate application improves the tolerance of celery grown under heat stress conditions

Temperature rise is one of the most challenging climate change impacts that increase the intensity of heat stress. In this investigated the production of celery (Apium graveolens var. rapaceum F1 hybrid)) was tested during the late season. The experiment was carried out during the two successive summer seasons of 2019 and 2020 in Giza Governorate, Egypt. The experimental design is a split-plot, the main plots consist of three low tunnel cover treatments, and three spray treatments with three replicates in sub-main plots. Results showed that the use of white net cover gave the highest vegetative growth and yield followed by the black net. Values of plant yield were 951, 765, and 660 g/plant for white, black and without cover, respectively, in the first season. The foliar application of 3 mM of potassium silicate produced the highest vegetative growth and yield compared to the control treatment. Referring to the effect of spray foliar application of potassium silicate on yield 1.5 mM (S1), 3 mM (S2), and control were 892, 795, and 689 g/plant in the first season, respectively. The best combination that delivered the highest vegetative growth and yield was a cover low tunnel with a white net combined with S2 foliar application.

Sample-Based Estimation of Tree Cover Change in Haiti Using Aerial Photography: Substantial Increase in Tree Cover between 2002 and 2010

Recent studies have used high resolution imagery to estimate tree cover and changes in natural forest cover in Haiti. However, there is still no rigorous quantification of tree cover change accounting for planted or managed trees, which are very important in Haiti’s farming systems. We estimated net tree cover change, gross loss, and gross gain in Haiti between 2002 and 2010 from a stratified random sample of 400 pixels with a systematic sub-sample of 25 points. Using 30 cm and 1 m resolution images, we classified land cover at each point, with any point touching a woody plant higher than 5 m classified as tree crown. We found a net increase in tree crown cover equivalent to 5.0 ± 2.3% (95% confidence interval) of Haiti’s land area. Gross gains and losses amounted to 9.0 ± 2.1% and 4.0 ± 1.3% of the territory, respectively. These results challenge, for the first time with empirical evidence, the predominant narrative that portrays Haiti as experiencing ongoing forest or tree cover loss. The net gain in tree cover quantified here represents a 35% increase from 2002 to 2010. Further research is needed to determine the drivers of this substantial net gain in tree cover at the national scale.

Study the Effect of Different Fruit Bunch Covering Materials on Bird’s Damage, Yield and Quality of Date Palm cv. Halawy in Western Rajasthan

Date palm fruits are damaged by bird’s attack which reduce their commercial value and thereby cause significant economic losses. The objective of this study was to find out the suitable fruit bunch covering material for reducing birds attack, increase yield and improve fruit quality. An investigation was carried out for study the effect of different fruit bunch covering materials on bird’s damage, yield and quality of date palm (Phoenix dactylifera L.) cv. Halawy at Date palm Research Center, Swami Keshwanand Rajasthan Agricultural University, Bikaner during the year 2019–20. The fruit bunches were subjected to six covering materials i.e., iron wire gauge, non-woven material, agro-shed net, insect proof net, cloth bag and fertilizer bags with one unbagged treatment (control). The fruits bunches were covered at kimri or gandora stages of maturity. The applied treatments were arranged in a randomized block design with three replicates and in each replication three tree were used. Different fruit bunch covering materials significantly influenced the maturity period of date palm (doka stage). Fruit bunches covered with fertilizer bag were matured earlier (109.21 days) in compared to uncovered fruit bunches (116.30 days). The yield of fruits was significantly increased by different fruit bunch covers, and maximum yield (5.89 kg/bunch and 30.68 kg/palm) was recorded in insect proof net fruit cover. The quality attributes viz., fruit weight (7.18 g), fruit length (5.42 cm), fruit diameter (2.80 cm), fruit volume (7.25 cc) and pulp weight (5.44 g) were significantly increased in fruits covered by insect proof net covering materials. However, attributes viz., stone weight, length of bunches, percentage of fruits retained after covering of bunches were found non-significant under different covering materials. The maximum TSS (40.10%), phenol content (0.83 mg/100 g), ascorbic acid (8.06 mg/100 g), total sugar (34.46%) and reducing sugar (31.80%) were significantly influenced and recorded maximum in insect proof net. While, the acidity (0.14%) and soluble tannin (4.46 mg/g) were significantly decreased in insect proof net. Fruit bunch covers minimized the bird’s damage in fruits, and there were no infestations of birds in iron wire gauge cover (0.00%) while, fertilizer bag cover and agro-shed net cover showed minimum bird’s infestation i.e., 1.00% and 1.61%, respectively. The highest bird’s damage (14.64%) of date palm fruits was recorded in unbagged fruits (control).The highest benefit cost ratio (4.58) was obtained in fertilizer bag fruit cover while, the lowest benefit cost ratio (0.94) was recorded in iron wire gauge fruit cover.

Rangeland Fractional Components Across the Western United States from 1985 to 2018

Monitoring temporal dynamics of rangelands to detect and understand change in vegetation cover and composition provides a wealth of information to improve management and sustainability. Remote sensing allows the evaluation of both abrupt and gradual rangeland change at unprecedented spatial and temporal extents. Here, we describe the production of the National Land Cover Database (NLCD) Back in Time (BIT) dataset which quantified the percent cover of rangeland components (bare ground, herbaceous, annual herbaceous, litter, shrub, and sagebrush (Artemisia spp. Nutt.) across the western United States using Landsat imagery from 1985 to 2018. We evaluate the relationships of component trends with climate drivers at an ecoregion scale, describe the nature of landscape change, and demonstrate several case studies related to changes in grazing management, prescribed burns, and vegetation treatments. Our results showed the net cover of shrub, sagebrush, and litter significantly (p < 0.01) decreased, bare ground and herbaceous cover had no significant change, and annual herbaceous cover significantly (p < 0.05) increased. Change was ubiquitous, with a mean of 92% of pixels with some change and 38% of pixels with significant change (p < 0.10). However, most change was gradual, well over half of pixels have a range of less than 10%, and most change occurred outside of known disturbances. The BIT data facilitate a comprehensive assessment of rangeland condition, evaluation of past management actions, understanding of system variability, and opportunities for future planning.

Spatial patterns of tree cover change at a dry forest margin are driven by initial conditions, water balance and wildfire

Increases in tree cover at dry forest margins are a global phenomenon. Yet, how pre-existing tree cover interacts with terrain and water balance to influence tree cover change is not well-understood, nor whether subsequent disturbances restore prior tree cover patterns or create novel patterns. To assess how terrain, water balance and pre-existing patterns of tree cover influenced late twentieth century tree cover change, and how subsequent wildfires altered tree cover patterns. We analyzed tree canopy cover at four sites at the forest-steppe ecotone on the eastern side of the Sierra Nevada, California, U.S.A., using aerial photographs from 1953/1955, 1999/2002 and 2016. Influences on tree cover change were assessed using statistical modeling, and tree cover in 1953/1955 was compared with post-wildfire tree cover in 2016. From 1953 to 2002, area with > 25% canopy cover increased by 1.5 to 5-fold and treeless area decreased by 17–111%. Mesic areas and areas of sparse tree cover close to existing forest tended to gain more canopy cover. Subsequent wildfires caused a mix of net tree cover loss, little change and gain relative to 1953/1955, but at all sites areas with > 25% cover and < 10% cover in 1953/55 experienced net losses and gains respectively by 2016. Accounting for initial tree cover and its configuration are crucial to assessing water balance and terrain effects on tree cover change. Our work highlights how wildfires can generate novel patterns of tree cover relative to historical baselines, especially following decades of fire exclusion.

ATSS Deep Learning-Based Approach to Detect Apple Fruits

In recent years, many agriculture-related problems have been evaluated with the integration of artificial intelligence techniques and remote sensing systems. Specifically, in fruit detection problems, several recent works were developed using Deep Learning (DL) methods applied in images acquired in different acquisition levels. However, the increasing use of anti-hail plastic net cover in commercial orchards highlights the importance of terrestrial remote sensing systems. Apples are one of the most highly-challenging fruits to be detected in images, mainly because of the target occlusion problem occurrence. Additionally, the introduction of high-density apple tree orchards makes the identification of single fruits a real challenge. To support farmers to detect apple fruits efficiently, this paper presents an approach based on the Adaptive Training Sample Selection (ATSS) deep learning method applied to close-range and low-cost terrestrial RGB images. The correct identification supports apple production forecasting and gives local producers a better idea of forthcoming management practices. The main advantage of the ATSS method is that only the center point of the objects is labeled, which is much more practicable and realistic than bounding-box annotations in heavily dense fruit orchards. Additionally, we evaluated other object detection methods such as RetinaNet, Libra Regions with Convolutional Neural Network (R-CNN), Cascade R-CNN, Faster R-CNN, Feature Selective Anchor-Free (FSAF), and High-Resolution Network (HRNet). The study area is a highly-dense apple orchard consisting of Fuji Suprema apple fruits (Malus domestica Borkh) located in a smallholder farm in the state of Santa Catarina (southern Brazil). A total of 398 terrestrial images were taken nearly perpendicularly in front of the trees by a professional camera, assuring both a good vertical coverage of the apple trees in terms of heights and overlapping between picture frames. After, the high-resolution RGB images were divided into several patches for helping the detection of small and/or occluded apples. A total of 3119, 840, and 2010 patches were used for training, validation, and testing, respectively. Moreover, the proposed method’s generalization capability was assessed by applying simulated image corruptions to the test set images with different severity levels, including noise, blurs, weather, and digital processing. Experiments were also conducted by varying the bounding box size (80, 100, 120, 140, 160, and 180 pixels) in the image original for the proposed approach. Our results showed that the ATSS-based method slightly outperformed all other deep learning methods, between 2.4% and 0.3%. Also, we verified that the best result was obtained with a bounding box size of 160 × 160 pixels. The proposed method was robust regarding most of the corruption, except for snow, frost, and fog weather conditions. Finally, a benchmark of the reported dataset is also generated and publicly available.

Phenolic Profile and Bioactive Potential of Stems and Seed Kernels of Sweet Cherry Fruit.

Every year, large quantities of stems and pits are generated during sweet cherry processing, without any substantial use. Although stems are widely recognized by traditional medicine, detailed and feasible information about their bioactive composition or biological value is still scarce, as well as the characterization of kernels. Therefore, we conducted a study in which bioactivity potential of extracts from stems and kernels of four sweet cherry cultivars (Early Bigi (grown under net cover (C) and without net cover (NC)), Burlat, Lapins, and Van) were examined. The assays included antioxidant (by 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene-linoleic acid bleaching assays), and antibacterial activities against important Gram negative and Gram positive bacterial human isolates. Profile and individual phenolic composition of each extract were determined by High-performance liquid chromatography (HPLC) analysis. Extracts from stems of cv. Lapins and kernels of Early Bigi NC presented high levels of total phenolics, flavonoids, ortho-diphenols and saponins. Excepting for cv. Early Bigi NC, major phenolic compounds identified in stems and kernels were sakuranetin and catechin, respectively. In cv. Early Bigi NC the most abundant compounds were ellagic acid for stems and protocatechuic acid for kernels. In all extracts, antioxidant activities showed a positive correlation with the increments in phenolic compounds. Antimicrobial activity assays showed that only stem’s extracts were capable of inhibiting the growth of Gram positive isolates. This new data is intended to provide new possibilities of valorization of these by-products and their valuable properties.

Biophysical and Socioeconomic Factors Associated to Deforestation and Forest Recovery in Brazilian Tropical Dry Forests

The determination of land cover changes (LCCs) and their association to biophysical and socioeconomic factors is vital to support government policies toward the sustainable use of natural resources. The present study aimed to quantify deforestation, forest recovery and net cover change in tropical dry forests (TDFs) in Brazil from 2007 to 2016, and investigate how they are associated to biophysical and socioeconomic factors. We also assessed the effects of LCC variables in human welfare indicators. For this purpose, we used MODIS imagery to calculate TDF gross loss (deforestation), gross gain (forest recovery) and net cover change (the balance between deforestation and forest recovery) for 294 counties in three Brazilian states (Minas Gerais, Bahia, and Piauí). We obtained seven factors potentially associated to LCC at the county level: total county area, road density, humidity index, slope, elevation, and % change in human population and in cattle density. From 2007 to 2016, TDF cover increased from 76,693 to 80,964 km2 (+5.6%). This positive net change resulted from a remarkable forest recovery of 19,018 km2 (24.8%), offsetting a large deforested area (14,748 km2; 19.2%). Practically all these cover changes were a consequence of transitions from TDF to pastures and vice-versa, highlighting the importance of developing sustainable policies for cattle raising in TDF regions. Each LCC variable was associated to different set of factors, but two biophysical variables were significantly associated both to TDF area gained and lost per county: county area (positively) and slope (negatively), indicating that large and flat counties have very dynamic LCCs. The TDF net area change was only associated (negatively) to the humidity index, reflecting an increase in TDF cover in more arid counties. The net increase in Brazilian TDF area is likely a result from an interplay of biophysical and socioeconomic factors that reduced deforestation and caused pasture abandonment. Although the ecological integrity and permanence of secondary TDFs need further investigation, the recovery of this semi-arid ecosystem must be valued and accounted for in the national forest restoration programs, as it would significantly help achieving the goals established in the Bonn agreement and the Atlantic Rain Forest pact.