Percent Canopy Cover Research Articles

Strong influence of trees outside forest in regulating microclimate of intensively modified Afromontane landscapes

Abstract. Climate change is expected to have detrimental consequences on fragile ecosystems, threatening biodiversity, as well as food security of millions of people. Trees are likely to play a central role in mitigating these impacts. The microclimatic conditions below tree canopies usually differ substantially from the ambient macroclimate as vegetation can buffer temperature changes and variability. Trees cool down their surroundings through several biophysical mechanisms, and the cooling benefits occur also with trees outside forest. The aim of this study was to examine the effect of canopy cover on microclimate in an intensively modified Afromontane landscape in Taita Taveta, Kenya. We studied temperatures recorded by 19 microclimate sensors under different canopy covers, as well as land surface temperature (LST) estimated by Landsat 8 thermal infrared sensor. We combined the temperature records with high-resolution airborne laser scanning data to untangle the combined effects of topography and canopy cover on microclimate. We developed four multivariate regression models to study the joint impacts of topography and canopy cover on LST. The results showed a negative linear relationship between canopy cover percentage and daytime mean (R2=0.65) and maximum (R2=0.75) temperatures. Any increase in canopy cover contributed to reducing temperatures. The average difference between 0 % and 100 % canopy cover sites was 5.2 ∘C in mean temperatures and 10.2 ∘C in maximum temperatures. Canopy cover (CC) reduced LST on average by 0.05 ∘C per percent CC. The influence of canopy cover on microclimate was shown to vary strongly with elevation and ambient temperatures. These results demonstrate that trees have a substantial effect on microclimate, but the effect is dependent on macroclimate, highlighting the importance of maintaining tree cover particularly in warmer conditions. Hence, we demonstrate that trees outside forests can increase climate change resilience in fragmented landscapes, having strong potential for regulating regional and local temperatures.

Black‐tailed deer seasonal habitat selection: accounting for missing global positioning system fixes

AbstractQuantitative models of black‐tailed deer (Odocoileus hemionus columbianus) habitat selection do not exist for Pacific Northwest landscapes but are needed to make predictions of how deer respond to timber harvest. We developed models to estimate habitat selection by black‐tailed deer within seasonal home ranges in the west‐central Cascade Mountains, Washington, USA, from 2008–2019. Even with moderately high global positioning system (GPS) fix success within summer and winter (both averages ≥0.87), we were concerned about landscape or vegetation characteristics causing fix success failure that would bias estimates of habitat selection. Year of GPS‐collar production, deer activity, and diel period (night, day, crepuscular) were associated with fix success. The odds of acquiring a fix were 2.53 times greater when the deer were inactive compared to active, and this difference was greater for those deer with higher average percent canopy cover within their home range. These relationships only explained a portion of the variation in the data and did not negate concerns about the effects of missing locations when estimating habitat selection, so we estimated deer habitat selection within summer and winter using an integrated step selection function (iSSF) and a probability of detection integrated step selection function (PDiSSF). The iSSF ignored missing fixes; the PDiSSF accounted for GPS fix failure due to the landscape and vegetation conditions. Covariates in the final summer PDiSSF included step length, an index of forage biomass, distance to cover‐forage edge, and distance to road. The winter model was similar but did not include forage biomass. We modeled the probability of detection in the PDiSSF as a function of canopy cover in both seasonal models. The standard iSSF resulted in estimates of stronger selection for areas with higher biomass, presumably because fix success was higher in these more open areas. Predictions of habitat selection from the final PDiSSF summer model evaluated well with independent data from a nearby study area. Evaluation of the final winter model was less promising. Ignoring missing GPS locations, even with an average fix success as high as 87%, would have led to different predictions of habitat selection by black‐tailed deer. We recommend that researchers consider the effect of habitat‐induced bias in fix success on the accuracy of estimates of habitat selection and consider using the PDiSSF to remove bias related to missing fixes.

Distribusi dan Kondisi Kesehatan Mangrove di Utara Labuan Bajo, Nusa Tenggara Timur


 
 
 
 This study aimed to determine the distribution, health condition, and mangroves' environmental conditions in northern Labuan Bajo. The mangrove species found at the observation sites were Rhizophora apiculata, R. stylosa, R. mucronata. Ceriops tagal, Sonneratia alba, Bruguiera gymnorrhiza, Xylocarpus granatum, X. moluccenis, Phemphis acidula. Mangroves north of Labuan Bajo are classified as healthy with moderate to good criteria ranging from 60.48% - 79.11%; the value of mangrove health is determined from several parameters such as canopy cover, which has a range of cover values ranging from 68.22% - 84.73% with an average percentage of the overall canopy cover at all observation points 79.72%, the density has a range value between 650 ponhon/ha -7950 trees/ha. The average tree diameter of the overall diameter of the grove reaches 844 cm. with an average environmental parameter value such as temperature reaching 31.03 °C, salinity is 34.4, pH average of 7.06 with the substrate in the entire observation area dominated by a muddy type of substrate that supports the growth of this species in addition to mangroves Rhizophora sp. species has excellent adaptability to the environment which causes this species to dominate in the observation area.
 
 
 

The Fuel Moisture Index Based on Understorey Hygrochron iButton Humidity and Temperature Measurements Reliably Predicts Fine Fuel Moisture Content in Tasmanian Eucalyptus Forests

Fine fuel moisture content (FFMC) is a key determinant of wildfire occurrence, behaviour, and pyrogeographic patterns. Accurate determination of FFMC is laborious, hence managers and ecologists have devised a range of empirical and mechanistic measures for FFMC. These FFMC measures, however, have received limited field validation against field-based gravimetric fuel moisture measurements. Using statistical modelling, we evaluate the use of the relationship between gravimetric FFMC and the Fuel Moisture Index (FMI), based on Hygrochron iButton humidity and temperature dataloggers. We do this in Tasmanian wet and dry Eucalyptus forests subjected to strongly contrasting disturbance histories and, hence, percentage of canopy cover. We show that 24 h average FMI based on data from Hygrochron iButtons 0.75 m above the forest floor provides reliable estimates of gravimetric litter fuel moisture (c. 1 h fuels) that are strongly correlated with near surface gravimetric fuel moisture sticks (c. 10 h fuels). We conclude FMI based on Hygrochron iButton data provides ecologists with an economic and effective method to retrospectively measure landscape patterns in fuel moisture in Tasmanian forests.

Mapping the spatial distribution and canopy cover of Lantana camara in the Zaka district of Zimbabwe

Alien plant invasions are a major ecological and management problem facing many parts of southern Africa. Invasive plants spread rapidly, negatively impacting native flora and fauna, agriculture and livelihoods. Lantana camara has invaded most parts of the Zaka District, a semi-arid communal area in Zimbabwe and the aim of this study was to assess and document the invasion status of the plant in the district. Mapping the occurrence of L. camara provides useful information for planning clearing efforts, modelling the invasion patterns and budgeting costs. We report the results of a study conducted in February 2015 where a combination of remote sensing and ground-based data collection was used to record lantana presence. Field assessment was done at 140 sampling sites (across seven land cover types), with sites chosen using a stratified random strategy. At each site the percent canopy cover of lantana was assessed by visual estimation and the data used to map the occurrence of lantana in each land cover type. Cover of lantana was highest in drainage lines (21.5%) and lowest in agricultural fields on grey and red soils (12%). Analysis of variance showed that differences in lantana cover amongst land cover types were not statistically significant, indicating that lantana is a generalist invader capable of thriving in various habitats within its range. Notwithstanding, habitat-specific invasion patterns were apparent and, as such, habitat targeted control efforts are advisable to achieve best results. We recommend cutting, stumping and onsite burning of lantana as the management method of choice and the periodic monitoring of the invasive plant in the district.

ІНФОРМАЦІЙНО-ДИНАМІЧНА МОДЕЛЬ УПРАВЛІННЯ СЕРВІСНИМ ВІДНОВЛЕННЯМ ПРАЦЕЗДАТНОСТІ ЗЕРНОЗБИРАЛЬНИХ КОМБАЙНІВ

The article presents the results of a study on the relationship and the possibility of mutual conversion between the normalized differentiated vegetation index (NDVI) and fractional green canopy cover (FGCC) in legumes. The purpose of the work is to provide proposals for models of mutual conversion between the vegetation indices. Materials and methods. The basis of the study was formed by the photographic materials of the leguminous crops, taken at different phases of growth and development on the fixed sites every 10 m of the experimental fields, obtained and automatically calculated to establish the percentage of green canopy cover in Canopeo mobile application. Experimental materials were obtained in 2021 in the experimental fields of the Institute of Irrigated Agriculture of NAAS and in 2016 in the experimental field of the AC "Radyanska Zemlya". Subsequently, the geotags and dates of shooting photographic materials were tied to the satellite NDVI values ​​obtained through the OneSoil AI platform for each of the studied crops (the difference in dates is up to 3 days). The established pairs of FGCC and NDVI for each crop were submitted for statistical analysis by polynomial regression. Statistical calculations and graphical work were performed in Microsoft Excel 365 spreadsheets. Results. It has been established that there is a close linear and nonlinear relationship between the FGCC and NDVI indices of the studied crops. The strength of the relationship is high, with a correlation coefficient in the range of 0.95-0.98 and a determination coefficient of 0.90-0.97. Polynomials of the second stage (nonlinear regression models) can be successfully used for mutual conversion between vegetation indices; the error in recalculation for most crops did not exceed 10 %. Conclusions. A high affinity between the normalized differential vegetation index and the percentage of green canopy cover in the leguminous crops (R2 within 0.90-0.97) has been proven. The closest relationship is observed for soybeans and beans compared to chickpeas and peas. Key words: peas, common beans, conversion, chickpeas, regression analysis, soybean.

Differential Regulation of Amino Acids and Nitrogen for Drought Tolerance and Poststress Recovery in Creeping Bentgrass

Effects of amino acids and nitrogen on plant regrowth or recovery from drought stress remain largely unknown. The objectives of this study were to examine how gamma-aminobutyric acid (GABA) or proline, alone and in combination, or inorganic nitrogen [ammonium nitrate (NN)] may differentially affect turf performance during drought stress and rewatering, and to determine which specific endogenous amino acids regulated by GABA, proline, or NN priming were associated with plant tolerance to drought stress and postdrought recuperation in cool-season grass species. Creeping bentgrass (Agrostis stolonifera cv. Penncross) planted in porous ceramic fritted clay medium were exposed to well-watered conditions or drought stress by withholding irrigation for 21 days in growth chambers. Plants were treated with water (untreated control), GABA, or proline alone and in combination, or NN through foliar spray before drought stress and every 7 days during the 21-day stress period. For postdrought recovery, at 21 days of drought treatment, plants were rewatered for 14 days to return soil water content to prestress levels. Plants treated with GABA or proline alone or in combination maintained higher turf quality (TQ), dark green color index (DGCI), and stolon length by 21 days of drought stress, whereas proline-treated plants also maintained higher leaf relative water content (RWC) during drought as well as longer stolon length during rewatering. Plants treated with NN maintained higher TQ and leaf RWC during drought and had improved percent canopy cover, DGCI, and stolon length during postdrought rewatering. Accumulation of endogenous amino acids under drought stress, including proline and alanine, for proline-treated creeping bentgrass may have contributed to the enhancement of drought tolerance and postdrought regrowth. Nitrogen-enhanced accumulation of GABA, proline, and glutamic acid may have played a role in active amino acid assimilation and subsequent postdrought regrowth. Results from this study indicate that GABA or proline were mainly effective in promoting the tolerance of creeping bentgrass to drought stress while inorganic NN was effective in promoting rapid postdrought recovery and regrowth potential through the activation of amino acid metabolism. Endogenous amino acids, including GABA, proline, alanine, and glutamic acid, may be used as biomarkers to select for drought-tolerant plants and biostimulant components for improvement of drought stress tolerance and poststress recovery in cool-season turfgrass species.

Status of seagrass ecosystem in Pane Island, North Sumatera

Pane Island is surrounded by seagrass meadows where Enhalus acoroides was the only species found. This small island is located in Tapanuli Tengah Regency, North Sumatera. The seagrass density and coverage was determined by using seagrass watch method, while the status was classified based on the Decree of the Minister of Environment of the Republic of Indonesia. The percentage of seagrass canopy cover shows that the seagrass is in poor and less affluent/unhealthy condition with 19.33 - 30.20%. Meanwhile, the seagrass density on Pane Island ranges from 58 – 107 ind/m2. The density is well related to the coverage, shown from the regression analysis between density and cover where the value of R2 is 0.65. The highest biomass was found at station II with aboveground biomass of 303.09 g/m2 and belowground biomass of 607.86 g/m2, while the lowest was at station I with aboveground biomass of 163.17 g/m2 and belowground biomass of 327.25 g/m2. The distribution and the status of the seagrass in Pane Island can become a database and inventory, so that follow-up related to the management and protection of seagrass ecosystems can be carried out effectively.

Influence of check dams on the activity pattern and morphometric traits of overwintering tadpoles in the Western Himalaya

Delaying metamorphosis in low-temperature conditions by anuran larvae known as ‘overwintering’ have been poorly studied, especially in terms of habitat ecology and behavioural aspects. The present study investigates some of the ecological aspects of overwintering tadpoles of the genus Nanorana in the Western Himalaya in an anthropogenically modified stream where check dams have altered the natural habitat, which can potentially influence the amphibian ecology. We present insights on the influence of check dams on the tadpole activity pattern and morphometric traits useful in the conservation planning of the narrowly distributed and understudied species, which are most sensitive to habitat modification.We monitored natural and modified pool habitats in the stream during winter and post-winter seasons based on the visual density of tadpoles to assess the diurnal and seasonal emergence pattern with associated habitat variables. Generalized Linear Mixed Modeling (GLMM) was used to understand the influence of various habitat variables on the visible density of tadpoles. Fine-scale temporal scan sampling of tadpoles was carried out to complement the understanding of the visible density variation and analyzed using circular plots and activity overlap estimation. Variation in morphometric traits was assessed using field morphometry and photogrammetry.Mean tadpole visible density at nighttime was higher in modified pools than natural pools during winter, but there was no statistically significant difference during daytime; the nocturnal pattern changed in the post-winter, where visible density was higher in natural pools. Tadpole visible density was influenced by the interaction of mean canopy cover with water temperature, instream cover items richness, mean canopy cover percentage, water temperature, leaf litter depth, water velocity and interaction of time of the day with pool modification. Tadpole activity patterns varied significantly between pool types during post-winter, where modified pool population increased daytime activity and thus the activity overlap reduced from winter (90.8%) to post-winter (64.5%). During both seasons, the mean body size of the natural pool population was significantly lower than the modified pool population; mean relative tail length was significantly lower in natural pools during post-winter; mean tail depth was significantly lower in natural pools during winter.The study presents evidence of the influence of anthropogenic habitat alterations on behaviour and morphometric traits of overwintering tadpoles, which needs to be further investigated. We also discuss the variation in nocturnal emergence, habitat selection and morphometric trait patterns in the modified habitat, potential reasons and similar behaviour in other aquatic organisms, which need to be considered while developing conservation strategies for the overwintering tadpoles in the region.

Integration of VIIRS Observations with GEDI-Lidar Measurements to Monitor Forest Structure Dynamics from 2013 to 2020 across the Conterminous United States

Consistent and spatially explicit periodic monitoring of forest structure is essential for estimating forest-related carbon emissions, analyzing forest degradation, and supporting sustainable forest management policies. To date, few products are available that allow for continental to global operational monitoring of changes in canopy structure. In this study, we explored the synergy between the NASA’s spaceborne Global Ecosystem Dynamics Investigation (GEDI) waveform LiDAR and the Visible Infrared Imaging Radiometer Suite (VIIRS) data to produce spatially explicit and consistent annual maps of canopy height (CH), percent canopy cover (PCC), plant area index (PAI), and foliage height diversity (FHD) across the conterminous United States (CONUS) at a 1-km resolution for 2013–2020. The accuracies of the annual maps were assessed using forest structure attribute derived from airborne laser scanning (ALS) data acquired between 2013 and 2020 for the 48 National Ecological Observatory Network (NEON) field sites distributed across the CONUS. The root mean square error (RMSE) values of the annual canopy height maps as compared with the ALS reference data varied from a minimum of 3.31-m for 2020 to a maximum of 4.19-m for 2017. Similarly, the RMSE values for PCC ranged between 8% (2020) and 11% (all other years). Qualitative evaluations of the annual maps using time series of very high-resolution images further suggested that the VIIRS-derived products could capture both large and “more” subtle changes in forest structure associated with partial harvesting, wind damage, wildfires, and other environmental stresses. The methods developed in this study are expected to enable multi-decadal analysis of forest structure and its dynamics using consistent satellite observations from moderate resolution sensors such as VIIRS onboard JPSS satellites.

Potential impacts of emerald ash borer and adaptation strategies on wildlife communities in black ash wetlands.

Black ash wetlands cover approximately 1.2 million ha of wetland forest in the western Great Lakes region, providing critical habitat for wildlife. The future of these wetlands is critically threatened by a variety of factors, including emerald ash borer (Agrilus planipennis; emerald ash borer [EAB]), which has been eliminating native populations of otherwise healthy ash throughout the Great Lakes region since it was discovered in 2002. To quantify the potential impacts of tree mortality from EAB on wildlife communities, we measured seasonal bird, mammal, and amphibian diversity in black ash wetlands using a dual approach: (1) documenting bird and amphibian species across 27 mature reference black ash wetlands in northern Minnesota, USA and (2) assessing how bird, mammal, and amphibian communities respond to experimental manipulations of black ash forests that emulate mortality and management strategies related to the potential impact of EAB. In total, 85 wildlife species were recorded for the entire study including 57 bird species, 5 amphibian species, and 23 mammal species. Results from the reference sites show that hydrologic regime, percentage of ash canopy cover, and understory cover were important habitat characteristics for bird and amphibian communities. Results from the experimental sites show there may be short-term increases in species richness for mammal and bird communities associated with changes in forest structure due to ash mortality; however, anticipated changes resulting from EAB-caused mortality, particularly the conversion of these sites to non-forested wetlands, will lead to significant shifts in bird and mammal community composition. Loss of ash may cause declines in forest-dependent species and increases in open-canopy and wetland-associated species. Additionally, whereas increased ponding extent and longer hydroperiods may be beneficial for some amphibian species, the loss of the forest canopy will result in an overall decrease in bird diversity and reduce forest connectivity for all species. Our results indicate the potential for significant large-scale impacts of black ash mortality on forest-associated wildlife. Management strategies that focus on establishing alternative trees species to maintain long-term forest cover and structural complexity in these wetlands will help to maintain and conserve wildlife diversity.

Plastic Mulch and In-row Spacing Effects on Sweetpotato Yield in Northwest Washington

Sweetpotato (Ipomoea batatas) production in the northern United States is limited due to the perceived barriers of a short growing season and relatively cool summer temperatures, yet recent studies have shown yield in northern regions can be greater than the national average when sweetpotatoes are grown with plastic mulch. A study was conducted in northwest Washington to evaluate the productivity of ‘Covington’ sweetpotato with polyethylene (PE) and soil-biodegradable (BDM) mulches and different in-row spacings (20, 30, and 38 cm) in 2019, and to test accessions resistant to wireworm (Agriotes sp. and Limonius sp.) in 2020. In 2019, slips were shipped from North Carolina, and after 4 days in transit, 60% to 70% died after transplanting in the field. By the end of the season, BDM deterioration reached 11% compared with 0.4% for PE mulch, but there were no differences due to mulch in plant establishment, growth, yield, or the proportion of storage roots damaged by wireworm. Total storage root yield was 22 t⋅ha−1 with PE mulch and 15 t⋅ha−1 with BDM. Percent canopy cover was greatest at 20-cm spacing later in the growing season, likely due to intermingling of vines from adjacent plants, whereas high percent canopy cover at 38-cm spacing was likely due to increased production of secondary vines per plant. Total yield was greatest with 20-cm plant spacing (20.4 t⋅ha−1), intermediate with 30-cm spacing (18.0 t⋅ha−1), and lowest with 38-cm spacing (17.0 t⋅ha−1). In contrast, the greatest number of storage roots per plant was produced with 38-cm plant spacing (3.4). There were more jumbo sweetpotatoes produced with PE mulch (3.4 t⋅ha−1) and with 30-cm spacing (3 t⋅ha−1), and the weight of U.S. No. 2 grade sweetpotatoes was greatest at 20-cm spacing (10.2 t⋅ha−1). Soil temperature was increased by 3 °C under the PE mulch and 2 °C under the BDM compared with bare ground. However, 98% of storage roots were observed to be severely damaged by wireworm in 2019, with more than 10 to 20 holes per storage root. For wireworm-resistant accessions in 2020, 16% of the storage roots were damaged by wireworm, with 1.7 to 4.0 holes per storage root. Total yield of accessions PI 666141 and 04-791 (45.5 t⋅ha−1 on average) was greater than the national average (24.7 t⋅ha−1). Overall, sweetpotatoes appear to be suitable for production in northwest Washington, but low yield in 2019 highlights the importance of healthy slips for successful production. Future research should evaluate cultivars with maximum adaptation to the region, techniques to reduce wireworm damage including genetic resistance, and the economics of producing sweetpotatoes in northern regions.

Comparative Analysis of Multi-Platform, Multi-Resolution, Multi-Temporal LiDAR Data for Forest Inventory

LiDAR technology is rapidly evolving as various new systems emerge, providing unprecedented data to characterize forest vertical structure. Data from different LiDAR systems present distinct characteristics owing to a combined effect of sensor specifications, data acquisition strategies, as well as forest conditions such as tree density and canopy cover. Comparative analysis of multi-platform, multi-resolution, and multi-temporal LiDAR data provides guidelines for selecting appropriate LiDAR systems and data processing tools for different research questions, and thus is of crucial importance. This study presents a comprehensive comparison of point clouds from four systems, linear and Geiger-mode LiDAR from manned aircraft and multi-beam LiDAR on unmanned aerial vehicle (UAV), and in-house developed Backpack, with the consideration of different forest canopy cover scenarios. The results suggest that the proximal Backpack LiDAR can provide the finest level of information, followed by UAV LiDAR, Geiger-mode LiDAR, and linear LiDAR. The emerging Geiger-mode LiDAR can capture a significantly higher level of detail while operating at a higher altitude as compared to the traditional linear LiDAR. The results also show: (1) canopy cover percentage has a critical impact on the ability of aerial and terrestrial systems to acquire information corresponding to the lower and upper portions of the tree canopy, respectively; (2) all the systems can obtain adequate ground points for digital terrain model generation irrespective of canopy cover conditions; and (3) point clouds from different systems are in agreement within a ±3 cm and ±7 cm range along the vertical and planimetric directions, respectively.

The role of fringing vegetation in supporting avian access to arid zone waterholes

ABSTRACT Access to drinking water is essential for many avian species in arid landscapes, especially in hot and dry periods when metabolic requirements for water increase. The role of fringing vegetation in facilitating surface water access by arid zone bird communities was investigated over a 14-month period during which water demand increased. Bird visitation to six long-lasting waterholes in the MacDonnell Ranges Bioregion in central Australia was recorded over two summers and one winter using camera traps. Species were assigned to functional classes based on their size and preferred foraging substrate. Generalised linear mixed models were used to test relationships between fringing vegetation variables and the independent trapping events for each functional class. Fringing vegetation was critical for small and intermediate-sized canopy foragers to access waterhole sites. Their activity declined to almost zero in areas where the nearest tree or shrub cover was greater than 10 m. The strength of this relationship was consistent as weather conditions became drier and hotter. However, activity of small and intermediate-sized canopy foragers was negatively related to the percent canopy cover of the nearest tree or shrub, potentially because sparse vegetative cover offers greater visibility when approaching the water’s edge. In contrast, ground forager and raptor activity at waterhole sites was unrelated to surrounding vegetation, and these groups frequently accessed water from open areas. Under future warming scenarios, small and intermediate canopy foragers may be vulnerable to predation if they are forced to access water at sites away from nearby fringing vegetation.

Tomato Yield and Quality Response to Water Application Technique and Management

Tomato (Lycopersicon esculentum Mill) is one of the most important and has the highest acreage of any vegetable crop in the world. Such quantitative analysis is based on the assessment of data from sequential collections of plant traits linked to environmental conditions, as well as yield potential under optimal growth conditions. The objective in this study was to evaluate the performance of tomato crop under furrow, basin and hosepipe irrigation techniques in Kabos, Serere District of Eastern Uganda. The materials and methods used in this study included tools like water pump (model DCX2-50D), Tomato variety Rionex, weighting scale, CROPWAT 8.0 software, CANOPEO software among others. Generally, quantitative techniques through several experiment designs were used. Daily and monthly weather variables, in-situ primary datasets of plant height, canopy cover percentages and fruit characteristics, and weight of harvested tomatoes were measured at three growth stages and analyzed using RCBD experiment with six treatments and four replications.
 Findings showed that overhead treatments had lowest rate of rotten yield compared to basin and furrow but had highest rate of discolored fruits attributed to sunshine and impact of water pressure during irrigation. Rotting of yield was highest in basin treatments. The rotting was attributed to water logging, poor drainage that accelerated fungal infection in the tomatoes. Furrow treatments had better drainage which reduced quantity of nonmarketable yield. There was no significant difference on the weight of tomatoes below 65g. This meant that fruit weight was independent of irrigation method. Treatments under hosepipe irrigation-overhead. Conclusively, water management practices have big impact on the crop yield giving a relationship that yield is directly proportional to water management practices, which however, should be followed by detailed soil and water analysis through such studies. The Safe-Water-for Food (SWFF) target can be reached and eventually reduce on the global hunger syndrome.

Tomato Yield and Quality Response to Water Application Technique and Management

Tomato (Lycopersicon esculentum Mill) is one of the most important and has the highest acreage of any vegetable crop in the world. Such quantitative analysis is based on the assessment of data from sequential collections of plant traits linked to environmental conditions, as well as yield potential under optimal growth conditions. The objective in this study was to evaluate the performance of tomato crop under furrow, basin and hosepipe irrigation techniques in Kabos, Serere District of Eastern Uganda. The materials and methods used in this study included tools like water pump (model DCX2-50D), Tomato variety Rionex, weighting scale, CROPWAT 8.0 software, CANOPEO software among others. Generally, quantitative techniques through several experiment designs were used. Daily and monthly weather variables, in-situ primary datasets of plant height, canopy cover percentages and fruit characteristics, and weight of harvested tomatoes were measured at three growth stages and analyzed using RCBD experiment with six treatments and four replications.
 Findings showed that overhead treatments had lowest rate of rotten yield compared to basin and furrow but had highest rate of discolored fruits attributed to sunshine and impact of water pressure during irrigation. Rotting of yield was highest in basin treatments. The rotting was attributed to water logging, poor drainage that accelerated fungal infection in the tomatoes. Furrow treatments had better drainage which reduced quantity of nonmarketable yield. There was no significant difference on the weight of tomatoes below 65g. This meant that fruit weight was independent of irrigation method. Treatments under hosepipe irrigation-overhead. Conclusively, water management practices have big impact on the crop yield giving a relationship that yield is directly proportional to water management practices, which however, should be followed by detailed soil and water analysis through such studies. The Safe-Water-for Food (SWFF) target can be reached and eventually reduce on the global hunger syndrome.

Tallgrass prairie wildlife exposure to spray drift from commonly used soybean insecticides in Midwestern USA

Insecticides are widely used in the Midwestern USA to combat soybean aphids (Aphis glycines), a globally important crop pest. Broad-spectrum foliar insecticides such as chlorpyrifos, lambda-cyhalothrin, and bifenthrin (hereafter, “target insecticides”) are toxic to wildlife in laboratory settings; however, little information exists regarding drift and deposition of these insecticides in fragmented tallgrass prairie grasslands such as those in Minnesota, USA. To address this information gap, target insecticide spray drift and deposition were measured on passive samplers and arthropods in grasslands adjacent to crop fields in Minnesota. Samples were collected at focal soybean field sites immediately following target insecticide application and at reference corn field sites without target insecticide application. Target insecticides were detected 400 m into grasslands at both focal and reference sites. Residues of chlorpyrifos, an insecticide especially toxic to pollinators and birds, were measured above the contact lethal dose (LD50) for honey bees (Apis mellifera) up to 25 m from field edges in adjacent grasslands. Chlorpyrifos residues on arthropods were below the acute oral LD50 for several common farmland bird species but were above the level shown to impair migratory orientation in white-crowed sparrows (Zonotrichia leucophrys). Deposition of target insecticides on passive samplers was inversely associated with distance from field edge and percent canopy cover of grassland vegetation, and positively associated with samplers placed at mid-canopy compared to ground level. Target insecticide deposition on arthropods had an inverse relationship with vertical vegetation density and was positively associated with maximum height of vegetation. Tallgrass prairie with cover ≥25 m from row crop edges may provide wildlife habitat with lower exposure to foliar application insecticides. Prairie management regimes that increase percent canopy cover and density of vegetation may also reduce exposure of wildlife to these insecticides.

Response of Vicia variabilis to Some Ecological Factors in the Zagros Forests of Iran

Abiotic environmental factors have a major impact on the distribution and performance of plant species. For this purpose, regarding the importance of Vicia variabilis in forage production and the possibility of using it in the improvement and reclamation of oak forest understory, this study aimed to investigate the effect of soil variables and topography on the response of this species using generalized additive models in the west of Iran. The results showed that the response pattern of V. variabilis along the gradient of clay, silt, and soil saturation moisture followed the monotonic increase model. Conversely, the response of this species along the gradient of sand percentage, bare soil percentage, and content of sulfate salts in the soil followed the monotonic decrease model. The species response pattern along the gradients of electrical conductivity, lime percentage, pH of soil, soil sodium ion, phosphorus, altitude, slope, stone and gravel percentage, and canopy cover percentage of the forest overstorey followed a unimodal model, and its optimal growth limit for these factors was 0.85 dsm–1, 5.10%, 7.26, 0.38 meql–1, 35 ppm, 1 650 m, 31%, 7%, and 25%, respectively. The results of phenological studies on V. variabilis during 2018 to 2020 showed that late June/early July was the most suitable time for livestock use of this species, and the best time to collect the seeds was mid-July to the early August. Regarding the response of this plant to the gradient of studied environmental factors, it is recommended to pay attention to its habitat characteristics and ecological requirements in improvement programs on oak forests understory vegetation.

Percentage of Mangrove Canopy Cover and Mollusks Abundance in Benoa Bay Mangrove Ecosystem

This research was conducted to determine the condition of the mangrove ecosystem based on its canopy cover and to determine the types of mollusks (Bivalves and Gastropods) associated with the Benoa Bay mangrove ecosystem. Hemispherical photography is a method for observing mangrove canopy cover and line transect method for mollusks. The composition of mangrove species found in the research location were five species, namely Rhizophora stylosa, Rhizophora mucronata, Rhizophora apiculata, Bruguiera gymnorrhiza, and Avicennia marina. The percentage of mangrove canopy cover in the Benoa Bay mangrove ecosystem is in a good category (average = 76.59%). There are eight types of mollusks found in the research location. There are two types of bivalves (Polymesoda bengalensis and Gafrarium pectinatum) and six types of gastropods (Nerita balteata, Nerita picea, Neritina turrita, Pila ampullacea, Cassidula aurisfelis, and Littoraria melanostoma). The relationship between the percentage of mangrove canopy cover and abundance of mollusks in the Benoa Bay mangrove ecosystem is very strong (r) of 0.920. The higher the percentage value of mangrove canopy cover, the higher the mollusks abundance.

The Use of Remote Sensing Data to Estimate Land Area with Forest Vegetation Cover in the Context of Selected Forest Definitions

(1) Background: Like many other countries, Poland is obliged to report forest area to the Climate Convention (UNFCCC Kyoto Protocol) and the Food and Agriculture Organization of the United Nations (FAO/UN). Differences between national and international forest definitions lead to differences between actual and reported forest area. Remote sensing is a useful tool for estimating forest area for reporting purposes. One of the most important parts of the estimation is the choice of a basal area to calculate the percentage of vegetation cover. (2) Methods: Height, crown projection area, and minimum complex area were used to classify the area with forest vegetation. Percentage canopy cover was determined using three different methods based on segmentation polygons, triangular grid and canopy height model pixels. The accuracy of the above methods was verified by manual vectorization performed on a selected set of test plots in the Milicz study area according to the international definitions. The differences were examined using three statistical metrics. (3) Conclusions: This paper compares for the first time methods for determining the area for which canopy cover is calculated (using data from (ALS) and discusses the differences between them in the context of accuracy (the correspondence between the results and the reference data) and the complexity of the process (time and effort required to perform the analysis). This is important in the context of reporting, estimating carbon stocks and biodiversity to mitigate the effects of climate change. Method 2 proved to be the most accurate method, Method 1 was found to be the worst option. Accuracy was better in the case of the Kyoto Protocol definition.