Levels Of Canopy Cover Research Articles

Forest canopy cover affects microclimate buffering during an extreme heat event

Increasing temperatures and extreme heat episodes have become more common with climate change. While forests are known to buffer increasing temperatures (relative to non-forested areas), whether this buffering is maintained under extreme temperature events is relatively unknown. Here we assess whether forests continue to buffer microclimate (specifically temperatures) during an extreme heat event: the Pacific Northwest (PNW) heat dome in June 2021. We use a combination of ground-based and regional climate data and find that forest understories were 3 °C cooler than a clear-cut area and 4 °C cooler than regional temperatures during the PNW heat dome. By examining forests with different levels of canopy cover we also found that the buffering capacity of forests is greater under denser canopies even under extreme heat events. Additionally, we found vertical variation in thermal buffering, with the greatest amount of buffering at the surface of the forest floor. Overall, our findings suggest that temperate coastal forests, that are known to buffer average temperatures, can also act as microclimate buffers during extreme heat events like the heat dome that occurred in the PNW in 2021. This could be good news for forest dwelling organisms that are sensitive to such extreme heat events.

Analysis of the environmental damage and agricultural utilization in Forest Area of Dieang Plateau, Central Java, Indonesia

Dieng Plateau is a renowned tourist attraction due to its captivating panoramas, protected forest, agricultural viability, and geothermal resources. However, encouraging social life forces the local community to depend on the surrounding forest by utilizing the forest area as agricultural land. These activities harm the environment. This study aimed to determine the level of environmental damage and agricultural utilization in forest area of Dieng Plateau. Data collection methods were observation and interviews, with a purposive determination of the sample. Data analysis was carried out spatially to determine the level of environmental damage. The results showed that the erosion rate in the Dieng Plateau was in the moderate (33-35 cm), heavy (86-100 cm) and very heavy class (92-235 cm). The level of canopy cover is in the moderately dense class (60%), sparse class (20-40%) and very sparse class (<20%). The level of land productivity is in the low class (40%), moderate class (45-53%), high class (70%) and very high (93%). The level of environmental management ranged from poor to excellent. The level of environmental damage in total is in the rather severe and damaged class. For this reason, it is necessary to implementing environmental damage control strategies by land rehabilitation and closely monitoring agricultural activities by the forest area management and local government authorities are essential measures.

Effect of Canopy Cover Level of Cacao and Shade Trees on Splash Erosion On Cacao Land

In smallholder cacao plantations, the protective crops used varied, so they have different effects on splash erosion. The management of land cover with a canopy of cacao and shade trees on cacao fields, aims to control of splash erosion. This study was conducted by directly measuring the magnitude of splash erosion under several levels of canopy cover. The magnitude of splash erosion was determined by measuring the depth of the eroded soil using the bottle cap method. The measurements were carried out every rain event (46 rain events with rainfall varied from 0.28 to 97.04 mm). The canopy cover level was determined by analyzing the images taken using a digital camera. The images were processed by Matlab software with closure approach. The data were analyzed by regression analysis to determine the relationship between canopy cover level and the depth of splash erosion that occurred. The results showed that the level of canopy cover influence the depth of splash erosion. In addition, this study indicates that the level of splash erosion not only influenced by the level of closure and rainfall, but also strongly influenced by the size of the leaf cover. Keywords: Cacao plantation, Canopy cover, Regression analysis, Splash erosion.

Where are the large trees? A census of Sierra Nevada large trees to determine their frequency and spatial distribution across three large landscapes

Large trees (≥76.2 cm/≥30″ DBH) and especially very large trees (≥101.6 cm/≥40″ DBH) are key structures of Sierra Nevada forests for their ecological function, habitat, and carbon storage. Many of these trees have been lost to historic harvest and more recently to drought and wildfires. Understanding the current frequency and distribution of these large trees is essential to understanding their ecological contribution and management needs. We used airborne lidar to census large trees across three Sierra Nevada landscapes (cumulatively 396 K ha) in lower (dominated by ponderosa pine and mixed conifer) and upper (dominated by red fir) montane forest zones. We used data from a network of Forest Inventory and Analysis (FIA) plots to interpret our lidar-based results for large tree frequency, species, and ages. The lidar data identified > 8 M large and > 2.7 M very large trees, and their mean densities were similar to those from FIA data. Large portions of our study areas had either no or low densities (<20) of large trees per hectare. We found that large and very large tree concentrations were spatially aggregated with most in denser patches containing 20 to 50 + large trees per hectare. Depending on the study area, these often sizable (>1000 ha) patches of dense large trees can cover 20% to 40% of the landscape. (Patches of denser very large trees cover less of the landscape, typically 5% to 10%). However, these large patches are rarely simple blocks. Instead, they typically form complex amorphous matrices interspersed with patches of forests containing shorter trees or non-forest cover. Crucially, almost all large trees were in stands with high canopy cover, suggesting horizontal fuel continuity and low resilience to future wildfires. For lower montane large trees, canopy cover versus large tree density showed almost a unimodal response with canopy cover of 60% to 80% for locations with > 20 large trees per ha. For upper montane large trees, canopy cover versus large tree density showed a more linear relationship for all three study areas. High levels of canopy cover, especially for lower montane forests, suggest settings in which infilling following decades of fire suppression have created overly dense stands with lower resilience to drought and wildfire. Other studies have documented substantial recent losses of these large trees to both factors. The high canopy cover within which almost all large trees exist emphasizes the need for treatment almost everywhere that large trees are present for lower montane forests. This likely will require treatments both within the stands that contain large trees and across the landscapes in which they are found.

Nitrous oxide and methane emissions from coffee agroforestry systems with different intensities of canopy closure

Agroforestry-based coffee production systems (AFs) contribute to climate change mitigation through carbon sequestration. However, it is unclear whether AFs produce lower nitrous oxide (N2O) and methane (CH4) emissions than the open-shade coffee production system. In addition, little to no evidence is available to explain the relationship between canopy cover levels and greenhouse gas (GHG) emissions in AFs. The aim of this study was to investigate N2O, CH4 and yield-scaled emissions in AFs with differing shade-tree canopy levels. Three canopy cover levels were identified: (i) dense shade (80 % canopy closure), (ii) medium shade (49 % canopy closure), and (iii) open-shade (full sun) production. To determine the effect of canopy cover on GHG emissions under varying soil fertility management practices, three soil fertilization strategies were included: (i) mineral fertilizer, (ii) compost, and (iii) control (i.e., without soil amendment). The results showed that N2O emissions were two-to-three times greater when there was dense canopy cover than from open-shade production. The effect of canopy cover on N2O emission was more pronounced under the mineral fertilizer treatment. CH4 emissions were 44–64 % greater under the open-shade production system than under AFs. The yield-scaled global warming potential of 1 kg of fresh coffee cherries was 0.72 kg CO2eq for open-shade production, 0.58 kg CO2eq for medium canopy cover and 0.52 kg CO2eq for dense canopy cover. This study provides the first evidence of the importance of considering canopy cover intensity when determining the spatial-temporal variations in GHG emissions from agroforestry systems.

THE INFLUENCE OF FOREST CANOPY COVER ON FRUIT-FEEDING BUTTERFLY COMMUNITIES IN THE HUU LIEN SPECIAL-USE FOREST, LANG SON PROVINCE

The alteration of tropical forest structures due to human activities can have negative impacts on various organism communities. The purpose of this study was to investigate how forest canopy cover affects the species composition and community structure of fruit-feeding butterflies in the karst ecosystems of the Huu Lien special-use forest, Lang Son Province. Three forest fragments with high (&gt;80%), medium (50-80%), and low (&lt;50%) levels of canopy cover were examined. We collected fruit-feeding butterflies using Van Someren-Rydon traps, with 30 traps deployed evenly across the three fragments from May 2022 to March 2023, recording 27 butterfly species of 557 individuals in total. The results indicated that the forest fragment with medium canopy cover had the highest species richness and diversity of fruit-feeding butterfly communities. Although most species were found in all three forest fragments, the Nonmetric Multidimensional Scaling (NMDS) analysis significantly separated the community structures of fruit-feeding butterflies among the three fragments. The two species, Kallima incognita Nakamura &amp; Wakahara and Stichophthalma fruhstorferi Röber, were mainly found in the forest fragment with high canopy cover and were considered as indicator species for this forest type. This study demonstrated the impact of forest canopy cover on the structure of fruit-feeding butterfly communities and emphasized the importance of forest canopy cover in conserving and maintaining insect diversity in karst ecosystems.

MEASURE OFF TERMITES DIVERSITY AND ABUNDANCE IN VARIOUS OILPALM TYPOLOGY IN TULANG BAWANG DISTRICT, LAMPUNG PROVINCE

The study was conducted in oilpalm land in Tiuh Tohou Village, Menggala, Tulang Bawang District of Lampung Province. This research aimed to measure off diversity and abundance in various oilpalm typologies in Tulang Bawang District, to study the relative abundanceof termites was highest in various oilpalm typology in Tulang Bawang and to find out the influence of environmental factors on termites diversity . The termites were sampled using the transect method. Data were analyzed using ANOVA and LSD test at 5% level of significance. Six termites genera were found acroos five typologies of oilpalm (old oilpalm, young oil palm, shrub/grass, cassava and swamp land), i.e. Globitermes, Odontetermes, Macrotermes, Hypotermes, Schedorhinotermes and Bulbitermes. However, it was estimated that three more other genera would be found if the number of samples (typology) was increase (extrapolated). There were differences in the diversity of termites accros oilpalm typologies (five genera in old oilpalam, four genera in young oilpalm, two genera in cassava, and only one genus in shrub/grass. The relative abundanceof termites was highest in the old oilpalm (18 counts), followed by young oilpalm (14 counts), cassava (5 counts) and shrub/grass (3 counts). The ranking of termites relative abundance had an exponential pattern, with Macrotermes and Bulbitermes being the most and the least abundance genera, respectively. Environmental factor that effect the richness of the termite genus are humidity, wood volume and litter weightand environmental factor that effect distribution and frequency of termite findings are influenced by frequency of termite findings are influenced by the level of canopy cover, humidity, wood volume, litter weight and litter organic C.

Utilization of drone for reclamation at the Batu Ampar block PT Timah Tbk

The Batu Ampar block is one of the ex-mining blocks in Bangka Regency where land revegetation has been carried out in 2019 and 2020. Observation of land realization is carried out by testing the accuracy of mapping using a base map from drone data and the success of the canopy cover level in accordance with the accuracy of the classification of the base map based on Regulations Head of the Geospatial Information Agency Number 15/2014. The results of processing and analysis show that the CE90 and LE90 accuracy test values for drone data geometry are 0.44 m and 0.86 m for the GCP georeference is said to be in class 3 on a scale of 1:2500 and class 1 on a scale of 1:5000. In the process without GCP georeference, the CE90 and LE90 values of 8.5 m and 6.8 m do not correspond to any class on the ideal scale for the layout of the Batu Ampar reclamation block mapping.

¿Es posible conservar la diversidad biológica y producir madera en las plantaciones de pino de la Patagonia argentina? Un estudio de caso

Forest plantations mitigate environmental problems and favor lowcarbon economies, but the growing demand for wood is driving the accelerated expansion of monocultures that are potentially harmful to biological diversity. In this research, the compatibility between taxonomic diversity of vascular plants and timber production of Pinus ponderosa was evaluated in stands with three levels of canopy cover, located in the steppe and the forest-steppe ecotone of Northwestern Patagonia from Argentina (40°5´ S - 71°12´ W). Soil moisture, diversity and site index were higher in the ecotone. The P. ponderosa cover was negatively correlated with the light intensity and diversity, and positively with the amount of litter and bare soil on the forest floor. After a 45-year rotation, the projected timber production was maximum for IDR≥800, but the diversity decreased dramatically. The best option to conserve diversity was to maintain IDR≤400 throughout the stand management cycle. However, the profitability of the production of quality wood would be negative with IDR&lt;500, regardless the site quality, area, initial density, management scheme and distance to the market for goods and services of the plantation. The negative correlation between the environmental and productive indicators would imply that there is no a silvicultural regime that simultaneously maximizes these objectives. This spatial incompatibility does not imply a priori discouraging the productive initiatives based on tree plantations. Forestry contributes to solving deep environmental, social and economic problems, particularly in the current scenario characterized by the increase in human population, the consumption of resources and the degradation and destruction of natural forests.

Comparing tree attributes derived from quantitative structure models based on drone and mobile laser scanning point clouds across varying canopy cover conditions

Complex canopy cover conditions often challenge the accurate measurement of many individual tree attributes that are pivotal to the sustainable management of forest resources. Advances in drone laser scanning (DLS) and mobile laser scanning (MLS) have enabled the acquisition of high-density point clouds with the potential to better resolve detailed tree structures. Yet, the quality of DLS and MLS data can be limited by occlusions and environmental complexities. To quantify the impacts of canopy cover on the tree attribute estimation, this study investigated the utility of DLS and MLS data both individually and combined. Considering the scanning characteristics, we examined direct fusion and a new strategy using a relative weighting scheme based on the probability density of vertical point distribution. We compared the accuracy of seven tree attributes derived from quantitative structure models (QSMs) based on (1) DLS, (2) MLS, (3) fused, and (4) weighted point clouds under low, moderate, and high canopy cover levels. We found that the weighted data improved the modelling efficiency of QSMs by ∼ 20% on average, compared to fused and MLS data. Across canopy cover levels, the fused and weighted data achieved comparable results and outperformed DLS/MLS data in estimating tree attributes. Specifically, diameter at breast height and crown base height were accurately extracted from the fused, weighted, and MLS data under low canopy cover with the concordance correlation coefficient (CCC) > 0.80. As canopy cover increased, they were best estimated using the fused data (CCC > 0.90, RRMSE < 22%). Height was accurate regardless of canopy cover, which was independent of data collection platforms (CCC > 0.80, RRMSE < 16%). The crown diameter was also well estimated by fused, weighted, and MLS data across canopy cover levels (CCC > 0.82, RRMSE < 19%). The total, stem, and branch volumes could be best modelled by the fused data with increasing canopy cover. Overall, the fusion of DLS and MLS point clouds allowed the retrieval of comprehensive tree-level information. However, forestry practitioners still need to evaluate the trade-offs in selecting the most appropriate platform for laser scanning data based on their needs. Future studies should also enhance the modelling of trees with complex branching structures to strengthen the extraction of diverse attributes.

Fire severity has lasting effects on the distribution of arboreal mammals in a resprouting forest

AbstractWildfire severity is assumed to be an important driver of habitat availability and species' distributions in forest ecosystems. Many studies have focused on the immediate or short‐term effects of fire severity in fire‐prone ecosystems, with much less focus on how long the effect of fire severity may persist. We examined the effect of fire severity on the distribution of arboreal mammals at 3 and 10 years post‐fire, in a temperate forest ecosystem dominated by eucalypts that have strong resistance and resilience to low and high severity fire, respectively. The study took place within areas affected by the 2009 Kilmore East‐Murrindindi wildfires in south‐eastern Australia. Sites were established across a gradient of fire severity (unburnt through to canopy consumption) and surveyed at 3 and 10 years following fire. Owing to low detection rates for many species, analyses were limited to greater glider (Petauroides volans) occurrence and arboreal species richness. At both 3 and 10 years post‐fire, the greater glider was restricted to unburnt forest or sites affected only by understorey fire, which acted as fire refugia. Greater gliders were absent from sites affected by high severity, canopy‐consuming fires at both points in time. Greater glider occurrence was associated with high levels of canopy cover (&gt;50%), which were typically those areas that were unburnt or burnt at low severity. The richness of arboreal mammals increased over time and was greater in unburnt or minimally affected forest. Our findings emphasize: (i) that fire severity is an important driver of the distribution of arboreal mammals; and (ii) the importance of recognizing longer‐term effects of fire severity in assessing species distributions, even in highly resilient forest communities. Recent advances in mapping fire severity provide new opportunities to assess the effects of fire severity on the distributional patterns of fauna in eucalypt forests.

Rainfall interception by mountain big sagebrush (Artemisia tridentataspp.vaseyana): Dryland shrub canopy cover affects net precipitation

AbstractCanopy interception loss is an important component of the water budget for many ecosystems, and may be particularly influential in semi‐arid shrublands where water is limiting. In this experiment, we quantified interception loss by mountain big sagebrush (Artemisia tridentata spp. vaseyana)using simulated rainfall events in the field. Various levels of canopy cover and rainfall intensities were tested to measure their effects on net precipitation and interception loss. Additionally, the comparisons were made between three methods of measuring shrub cover to enhance the scalability of results. Stands of sagebrush from 20% to 50% canopy cover intercepted 18.5 ± 12.5% of incoming precipitation. Percent interception loss differed by 13.7% between the high and low cover classes, indicating that net precipitation may be significantly reduced under mature, dense stands of sagebrush. Hemispherical photography was a viable method for estimating canopy cover in this vegetation type. Interception loss by sagebrush was 14% lower on average than pinyon and juniper measured in the same watershed. Results from this study quantified the effects of sagebrush canopy on rainfall interception and improved understanding of vegetation dynamics in the sagebrush steppe.

Evaluating the potential of urban areas for bat conservation with citizen science data

Global change, including urbanisation, threatens many of the >1400 bat species. Nevertheless, certain areas within highly urbanised cities may be suitable to harbour bat populations. Thus, managing urban habitats could contribute to bat conservation. Here, we wanted to establish evidence-based recommendations on how to improve urban spaces for the protection of bats. In a team effort with >200 citizen scientists, we recorded bat vocalisations up to six times over the course of 2 years at each of 600 predefined sites in the Berlin metropolitan area. For each species we identified the preferred and non-preferred landscape features. Our results show that artificial light at night (ALAN) had a negative impact on all species. For soprano pipistrelles and mouse-eared bats ALAN had the largest effect sizes among all environmental predictors. Canopy cover and open water were especially important for bat species that forage along vegetation edges and for trawling bats, respectively. Occurrence probability of species foraging in open space decreased with increasing distance to water bodies. On a larger scale, impervious surfaces tended to have positive effects on some species that are specialised on foraging along edge structures. Our study constitutes an important contribution to the growing body of literature showing that despite the many negative impacts of urbanisation on wildlife, urban environments can harbour bat populations if certain conditions are met, such as access to vegetation and water bodies and low levels of ALAN. Our findings are of high relevance for urban planners and conservationists, as they allow inferences on how to manage urban spaces in a bat-friendly way. We recommend limiting ALAN to the minimum necessary and maintaining and creating uninterrupted vegetated corridors between areas with high levels of canopy cover and water bodies, in which ALAN should be entirely avoided.

Density management strategy for overstory and understory of urban woodland based on ecological size-density allometry

Urban woodland is a dominant landscape element in supporting sustainability of urban systems. The aesthetic, ecological and psychological benefits provided by urban woodland are closely related to characteristics of the overstory and understory. The distribution and dynamics of tree canopy cover has been well elucidated, however, few studies focused on functioning and structure of urban understory and the interaction between different vegetation layers. In this study, ecological size-density allometry obtained through linear, quadratic and piecewise linear models was employed to quantify the resource competition of understory vegetation and effects of overstory canopy cover on understory in Shanghai metropolitan area of China. We found that canopy cover shapes the size-density pattern rather than affecting biomass and density directly. Size-density allometric relationships from piecewise linear models provided the optimal planting density under different canopy cover levels. Considering the linkage between vegetation layers and resource competition, we proposed that middle canopy cover of overstory (60%–80%) and relative low density of understory herb (175 m−2) is an optimal management strategy for maintaining high ecosystem services and functioning of urban woodlands.

Post‐disturbance canopy recovery and the resilience of Europe’s forests

AbstractAimForest ecosystems around the globe are facing increasing natural and human disturbances. Increasing disturbances can challenge forest resilience, that is, the capacity of forests to sustain their functions and services in the face of disturbance. Quantifying resilience across large spatial extents remains challenging, as it requires the assessment of the ability of forests to recover from disturbance. Here we analysed the resilience of Europe’s forests by means of satellite‐based recovery and disturbance indicators.LocationContinental Europe (35 countries).Time period1986–2018.Major taxa studiedGymnosperm and angiosperm woody plant species.MethodsWe used a comprehensive set of manually interpreted reference plots and random forest regression to model annual canopy cover from remote sensing data across more than 30 million disturbance patches in Europe over the time period 1986–2018. From annual time series of canopy cover, we estimated the time it takes disturbed areas to recover to pre‐disturbance canopy cover levels using space‐for‐time substitution. We quantified forest resilience as the ratio between canopy disturbance and recovery intervals, with critical resilience defined as forest areas where canopy disturbances occurred faster than canopy recovery.ResultsOn average across Europe, forests recover to pre‐disturbance canopy cover within 30 years. The resilience of Europe’s forests to disturbance is high, with recovery being &gt; 10 times faster than disturbance on 69% of the forest area. However, 14% of Europe’s forests had low or critical resilience, with disturbances occurring as fast or faster than forest canopy can recover.Main conclusionsWe conclude that Europe’s forests are widely resilient to past disturbance regimes, yet changing climate and disturbance regimes could erode resilience.

Behavioral Variation in the Pygmy Halfbeak Dermogenys collettei: Comparing Shoals With Contrasting Ecologies

Variation in biotic and abiotic factors among populations affects individual behaviors by transforming the social landscape and shaping mating systems. Consequently, describing behaviors in natural populations requires consideration of the biological and physical factors that different individuals face. Here, we examined variation in socio-sexual and locomotor behaviors in a small, livebearing, freshwater fish, the pygmy halfbeak Dermogenys collettei, across natural populations in Singapore. The pygmy halfbeak is a surface feeding fish that spends most of the time near the water surface, making it ideal for non-invasive behavioral observations. We compared behaviors between sexes among 26 shoals while simultaneously accounting for environmental variation. We demonstrated that sexual interactions and locomotor behaviors differed among shoals with varying levels of canopy cover and water flow. Specifically, in areas with greater canopy cover, sexual interactions decreased, whereas time spent in a stationary position increased. Sexual interactions were more numerous in still water, where fish spent less time swimming. Variation in the expression of socio-sexual and locomotor behaviors were not associated with differences in the amount of aquatic vegetation, water depth or halfbeak shoal size. Agonistic interactions were robust to environmental effects, showing little variation among environments. However, there were strong sex effects, with males performing more agonistic behaviors and spending less time in a stationary position compared to females, regardless of the environment. Moreover, sexual interactions, measured as actively performed by males and passively received by females, were on average more frequent in males than in females. Our findings help us explore the proximal causes of intraspecific behavioral variation and suggest that fundamental information on socio-sexual behaviors from wild populations can lead to a better understanding of how sexual selection operates when the strength of natural selection varies across environments.

Urban Landscape Heterogeneity Influences the Relationship between Tree Canopy and Land Surface Temperature

Urban trees play a key role in alleviating elevated summertime land surface temperatures in cities. However, urban landscape influences the capacity of urban trees to mitigate higher temperatures. We propose that both developed land characteristics and tree cover should be considered to accurately estimate the mitigation effects of canopy cover. We subclassified original land cover based on the canopy cover ratio to capture the within-land cover heterogeneity. We selected two coastal cities with different summertime climatic conditions: Seattle, Washington, USA, and Baltimore, Maryland, USA. We used Landsat-based grid cells (30 m × 30 m) as our spatial analytical unit, with corresponding land surface temperature, canopy area, canopy compactness, population size, and National Land Cover Database (NLCD)-based land cover group. We first used grouped boxplots, Kruskal–Wallis H tests, and post-hoc multiple comparison tests to detect the distribution of land surface temperatures by the land cover group. We then introduced statistical models to test the group effects on the relationship between land surface temperatures and canopy cover variables. We found: (1) land surface temperature increases with level of development, (2) land surface temperature decreases with canopy cover level, (3) the magnitude of the mitigation effects from canopy area differs based on development level and current canopy cover, (4) the differing efficacies of canopy area in decreasing land surface temperature follows a nonlinear threshold relationship, and (5) compactness of canopy cover was not significant in reducing the land surface temperature. These findings suggest the importance of considering heterogeneous canopy cover within developed land cover classes in urban heat island research. Tree planting strategies need to consider the nonlinear relationships between tree canopy cover and land surface temperature alongside environmental equity concerns.

Interactions of Soil and Vegetation Determine Habitat for Southeastern Pocket Gopher (Geomys pinetis)

Pocket gophers (Geomyidae) require soils amenable to burrowing and vegetation communities that provide adequate foods. We examined the interplay of soil texture and vegetation structure in determining site occupancy of the southeastern pocket gopher (Geomys pinetis), a species of conservation concern throughout its range. Using a case-control sampling design, we compared vegetation structure and soil texture between occupied and unoccupied sites in southeastern Alabama. All occupied sites had soil clay content ≤8.05% at 0–20 cm depth. In logistic regression modeling, clay content had overwhelming support as the most important single habitat variable distinguishing occupied from unoccupied sites. Based on soil results, we focused our examination of vegetation structure on the subset of our sites with <10% clay at 0–20 cm depth. Relative odds of occupancy were highest at intermediate levels of canopy cover; however, canopy cover at occupied sites ranged widely. Compared to unoccupied sites, occupied sites contained less midstory cover and greater ground cover of graminoids and shrubs. Our results demonstrate that although vegetation structure is important in determining site suitability, soil texture may be an overriding constraint limiting potential habitat for this species. Conservation actions for southeastern pocket gophers such as habitat restoration and population translocations should ensure that target sites have suitable low-clay soils.

Interactions of Soil and Vegetation Determine Habitat for Southeastern Pocket Gopher (Geomys pinetis)

Pocket gophers (Geomyidae) require soils amenable to burrowing and vegetation communities that provide adequate foods. We examined the interplay of soil texture and vegetation structure in determining site occupancy of the southeastern pocket gopher (Geomys pinetis), a species of conservation concern throughout its range. Using a case-control sampling design, we compared vegetation structure and soil texture between occupied and unoccupied sites in southeastern Alabama. All occupied sites had soil clay content ≤8.05% at 0–20 cm depth. In logistic regression modeling, clay content had overwhelming support as the most important single habitat variable distinguishing occupied from unoccupied sites. Based on soil results, we focused our examination of vegetation structure on the subset of our sites with <10% clay at 0–20 cm depth. Relative odds of occupancy were highest at intermediate levels of canopy cover; however, canopy cover at occupied sites ranged widely. Compared to unoccupied sites, occupied sites contained less midstory cover and greater ground cover of graminoids and shrubs. Our results demonstrate that although vegetation structure is important in determining site suitability, soil texture may be an overriding constraint limiting potential habitat for this species. Conservation actions for southeastern pocket gophers such as habitat restoration and population translocations should ensure that target sites have suitable low-clay soils.

Effect of canopy cover level on solar radiation for conservation plant photosynthesis under the stand of cocoa plants

Land degradation, which is caused by erosion, is one of the causes of the decline in the quality of cocoa plants. Vegetative soil conservation technology is one of the solutions to soil conservation on land that already has plants. The obstacle to conservation plant cultivation is its existence under the stand of plants so that solar radiation is limited for photosynthesis. This study aims to determine the level of canopy cover that can pass solar radiation for photosynthesis in conservation plants under the stand of cocoa plants. Retrieval of canopy cover data obtained through direct measurement using photo images and processed using MATLAB Image Processing Toolbox with closure approach. Solar radiation measured using the NHGH09BU Photosynthetic Active Radiation (PAR) sensor. The sensor is connected to the Arduino UNO microcontroller module. The results showed that the smaller the canopy cover, the duration of radiation that can support photosynthesis is longer. Likewise, the total active radiation for photosynthesis is inversely proportional to the percentage of canopy closure, which is the effect of the duration of active radiation. Radiation above 300 Watt/m2 occurs between 10.30 AM - 01.00 PM with the highest value 483 Watt/m2 which occurs at 11.00 AM. Total solar energy is inversely proportional to the percentage of canopy closure and is a linear relationship with R2> 0.9.