Integrating occupancy modeling and interview data for corridor identification: A case study for jaguars in Nicaragua

Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6 × 6 km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82–100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining ‘proportion of area occupied’, we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as ‘probability of habitat used’. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands.     

Recent progress in omics and biotechnological approaches for improved mango cultivars in Pakistan

Genetic Resources and Crop Evolution - Mango (Mangifera indica L.) is an important fruit crop throughout the world. Consequently, due to its excellent nutritional value and delicious taste, it is...     

基于深度学习与激光点云的橡胶林枝干重建及参数反演

树木的几何建模在林木性状评价、森林动态经营管理与可视化研究中具有重要意义。现今,从激光雷达（Light Detection And Ranging,LiDAR）数据中重建树体三维模型并精准获取林木空间枝干结构参数是数字林业发展的必然趋势。该研究提出了一种深度学习与计算机图形学相融合的树木骨架重建与参数反演方法。该方法以PR107、CATAS 7-20-59、CATAS 8-79三个品种的橡胶树为实验对象,首先,采用背包移动激光雷达获取三个橡胶树品种的样地数据,并通过体素剖分和数据增广策略来构建橡胶树训练样本集。其次,构造由四层特征编码层和特征解码层所组成的点云分类深度学习网络,并包含优化的PointConv模块与不同尺度的特征插值模块,以实现在多尺度条件下,全面考虑点云的全局和局部优化特征,引导网络实现枝叶点云的精确分类。最后,面向分类后的枝干点云,运用计算机图形学的空间连通性算法与圆柱拟合策略,重建树木骨架模型,并自动解决叶子点云与对应的一级枝干归属问题,进而在叶团簇尺度下开展对单株树的精细描述与参数反演。通过对三块橡胶树测试样地的验证和与实测值的比对表明,该研究提出的深度学习网络枝叶分类总体准确率在90.32%以上。骨架重建与叶团簇分析结果显示,PR107品种橡胶树具有较为发散的树冠、最大的分枝夹角和叶团簇体积;CATAS 7-20-59品种橡胶树冠呈花瓶型,分枝夹角和叶团簇体积较小;而CATAS 8-79品种橡胶树尽管胸径最粗,但不耐寒害处于落叶期导致冠积最小。同时,反演得到的橡胶树一级枝干直径与实测值比对为：决定系数R2不低于0.94,均方根误差（Root Mean Square Error,RMSE）小于3.01 cm;主枝干与一级枝干的分枝角为：决定系数R2不低于0.91,均方根误差RMSE不高于4.94°。同时发现橡胶树一级枝干的直径与对应的叶团簇体积呈正相关分布。该研究将人工智能的理论模型应用于林木的激光点云数据处理中,为林木激光点云的智能化分析与处理提供了新颖的解决思路。     

Impact of promotion of mango and liver as sources of vitamin A for young children: a pilot study in Burkina Faso

OBJECTIVE: To assess the effectiveness of a behaviour change approach, with or without financial support, in improving vitamin A (VA) intake and serum retinol concentration through mango and liver consumption by children. DESIGN: A parallel design (no control area) was used to assess changes in VA intake and serum retinol over a 15-week period. SETTING AND SUBJECTS: A pilot study was implemented in the Department of Kokologho, a rural area in central west Burkina Faso. One hundred and fifty children aged 2-3 years were randomly selected and assigned to two treatment groups: PA$$ (promotional activities and financial support) and PA (promotional activities). RESULTS: The intervention significantly increased (P < 0.001) total VA intake by 56% in PA$$ and by 50% in PA. VA intake from liver increased significantly (P < 0.001) from 12.7 +/- 23.5 to 155.3 +/- 56.3 microg retinol activity equivalents (RAE) in PA$$ and from 21.6 +/- 29.7 to 135.3 +/- 44.9 microg RAE in PA. Changes in VA intake from liver were significantly higher (P = 0.004) in PA$$ compared with PA. Mean serum retinol concentration increased significantly by 26% (P < 0.001) in PA$$ and 30% (P < 0.001) in PA. Changes in serum retinol concentration (0.13 micromol l(-1) in PA$$ vs. 0.17 micromol l(-1) and in PA) did not differ significantly (P = 0.455) between groups over the intervention. CONCLUSION: Promotional activities on mango and liver intake effectively increased VA intake and serum retinol concentrations. Although an additional beneficial effect of financial support on liver intake was observed, this did not translate into a further increase in serum retinol concentration.     

Peak functions for modeling high resolution soil profile data

Parametric and non-parametric depth functions have been used to estimate continuous soil profile properties. However, some soil properties, such as those seen in weathered loess, have anisotropic peak-shaped depth distributions. These distributions are poorly handled by common parametric functions. And while nonparametric functions can handle this data they lack meaningful parameters to describe physical phenomena in the depth distribution of a property such as a peak, an inflection point, or a gradient. The objective of this work is to introduce the use of asymmetric peak functions to model complex and anisotropic soil property depth profiles. These functions have the advantages of providing parameters, which quantify or describe pedogenic processes. We demonstrate the application of the Pearson Type IV (PIV) and the logistic power peak (LPP) functions to high resolution soil property depth profiles measured by diffuse reflectance spectroscopy in a claypan soil landscape of Northeastern Missouri, USA. Both peak functions successfully fit clay, silt, and pH data for an example soil profile from a summit landscape position (R² = 0.90 for pH and 0.98 for silt and clay). The LPP function was further demonstrated to fit clay depth distribution for a shoulder, backslope, footslope, and a depositional landscape position (R² = 0.98, 0.96, 0.96, 0.91). Relationships between the fitted parameters of these profiles were useful to describe landscape trends in their morphological features and show promise to continuously describe pedogenic processes in three dimensions. Peak functions are a useful companion to high-resolution soil profile data collected by sensors and their combined use may allow more intensive mapping and better explanation of soil landscape variability.     

Simplified tree crown model using standard forest mensuration data for Scots pine

Crown profiles of 260 Scots pines in central Finland were measured using a new method developed in the study, and a simple model for crown shape, belonging to the Lamé curve family, was derived using these data. Relatively accurate estimates of the crown maximum radius and its height, parameters needed for application of the model, were obtained using breast height diameter (dbh) and tree height. Results suggest that the model could potentially be used to generate the crown shape directly from routine stand data.     

A general approach to modeling and analysis of species abundance data with extra zeros

A general method for the analysis of ecological count data with extra zeros is presented using a Markov birth process representation of discrete distributions. The method uses a non parametric formulation of the birth process to model the residual variation and therefore allows the data to play a greater role in determining an appropriate distribution. This enables a more critical assessment of covariate effects and more accurate predictions to be made. The approach is also presented as a useful diagnostic tool for suggesting appropriate parametric models or verifying standard models. As an ill ustrative example, data describing a bundance of a species of possum from the montane ash forests of the central highlands of Victoria, southeast Australia, is considered.     

Assessment of SoilGrids data for soil erosion estimation at watershed scale: A case study in northern Thailand

Soil erosion has been identified as one of the most destructive forms of land degradation, posing a threat to the sustainability of global economic, social and environmental systems. This underscores the need for sustainable land management that takes erosion control and prevention into consideration. This requires the use of state-of-the-art erosion prediction models. The models often require extensive input of detailed spatial and temporal data, some of which are not readily available in many developing countries, particularly detailed soil data. The soil dataset Global Gridded Soil Information (SoilGrids) could potentially fill the data gap. Nevertheless, its value and accuracy for soil erosion modelling in the humid tropics is still unknown, necessitating the need to assess its value vis-à-vis field-based data. The major objective of this study was to conduct a comparative assessment of the value of SoilGrids and field-based soil data for estimating soil loss. Soil samples were collected from five physiographic positions (summit, shoulder, back slope, foot slope, and toe slope) using the soil catena approach. Samples were collected using a 5-cm steel sample ring (undisturbed) and a spade (disturbed). Data of the landform, predominant vegetation types, canopy cover, average plant height, land use, soil depth, shear strength, and soil color were recorded for each site. The soil samples were subjected to laboratory analysis for saturated hydraulic conductivity, bulk density, particle size distribution, and organic matter content. Pedotransfer functions were applied on the SoilGrids and field-based data to generate soil hydrological properties. The resultant field-based data were compared with the SoilGrids data for corresponding points/areas to determine the potential similarities of the two datasets. Both datasets were then used as inputs for soil erosion assessment using the revised Morgan-Morgan-Finney model. The results from both datasets were again compared to determine the degree of similarity. The results showed that with respect to point-based comparison, both datasets were significantly different. At the hillslope delineation level, the field-based data still consistently had a greater degree of variability, but the hillslope averages were not significantly different for both datasets. Similar results were recorded with the soil loss parameters generated from both datasets; point-based comparison showed that both datasets were significantly different, whereas the reverse was true for parcel/area-based comparison. SoilGrids data are certainly useful, especially where soil data are lacking; the utility of this dataset is, however, dependent on the scale of operation or the extent of detail required. When detailed, site-specific data are required, SoilGrids may not be a good alternative to soil survey data in the humid tropics. On the other hand, if the average soil properties of a region, area, or land parcel are required for the implementation of a particular project, plan, or program, SoilGrids data can be a very valuable alternative to soil survey data.     

Direct comparison of individual substrate utilization from a CLPP study: A new analysis for metabolic diversity data

For over a decade, community level physiological profile (CLPP) assays, which assess a microbial community's capacity to metabolize specific sole carbon sources under defined laboratory conditions, have been popular for study of environmental soil samples. One such assay, BiOLOG™ allows for the colorimetric measurement of metabolism through the reduction of a tetrazolium dye, which yields optical density (OD) data for each substrate. Bacterial communities are extracted from soil and 150 μL of this extract is inoculated directly into each well of the microtitre plate. The combined metabolic data obtained are most often analyzed with multivariate statistical analyses, such as principal component analysis (PCA). The objectives of this study were (1) to develop a simple, visual, statistically valid method of determining community capabilities to utilize specific substrates in CLPP studies and (2) to test the number of samples needed for such discrimination to be reliable. This was done by direct comparison of the OD values obtained for two closely related microbial communities (surface and subsurface soil), plotted against a one-to-one (y=x) line. Due to variability in the portion of the soil microbial community inoculated into the individual test wells, the accuracy of the method was dependent on the number of replicates analyzed. A variety of data set sizes were tested, from n=3 samples/soil depth to n=40 samples/depth. The method was statistically valid for all data sets tested. Those substrates that deviated from the one-to-one line consistently had F values greater than 1. Additionally, data sets of n=30,35 and 40 samples/depth consistently allowed identification of the eight substrates whose metabolism varied significantly between the two test soil communities. In conclusion, this one-to-one comparison has been shown to be a statistically valid analytical method to compare individual substrate usage between soils.     

Population baseline data for monitoring genetic diversity loss for 2010: A case study for Brassica species in the UK

The Convention on Biological Diversity and the subsequent International Treaty on Plant Genetic Resources for Food and Agriculture have proved a watershed in plant genetic resources (PGR) conservation and consequent initiatives have set various PGR conservation targets to be met by 2010. The aim of our paper is to develop ideas and issues concerning the monitoring of natural genetic resources: particularly in terms of developing a baseline from which to measure levels of genetic diversity. Three species of Brassica (B. nigra, B. oleracea, B. rapa) found wild in the UK were assessed for levels of genetic diversity using AFLP. The relationship between genetic distribution and ecogeographic distribution was considered for each species to determine patterns that may be useful in formulating conservation strategies. Genetic distance between populations of B. nigra and B. rapa were correlated to geographic distance. Levels of genetic polymorphism in B. oleracea were correlated to soil pH while in B. rapa they were correlated to soil coarseness. In terms of PGR conservation these findings may suggest an emphasis toward in situ conservation of a selection of disparate populations would be appropriate where possible as such adaptations may be lost in ex situ collections.     

Estimating survival from joint analysis of resighting and radiotelemetry capture-recapture data for wild animals

Biologists often use more than one marking technique in wildlife studies. For each of the mark types, it is common to conduct a separate analysis of the recapture data to estimate parameters of interest, such as survival rates. Two data types that can be used in estimating survival rates are resighting and radiotelemetry data. The Cormack-Jolly-Seber model is commonly used to analyze the resighting data, while the Kaplan-Meier product limit estimator, modified for staggered entry of animals, is used to analyze the radi otelemetry data. In a study where some animals receive two types of tags and others receive just one tag type, the separate Cormack-Jolly-Seber and Kaplan-Meier analyses do not exploit all of the information in the combined data sets. In this article, we propose a model and likelihood for the combined analysis of resighting and radi otelemetry data. In comparison with the separate analyses, this richer model provides more information about the biology and sampling processes. For example, the richer model permits assessment of assumptions required by the separate analyses and allows estimation of additional parameters. We apply the model to annual resighting and monthly telemetry data from a population of snail kites in Florida. The snail kite is a threatened species of bird in the United States, and our results on survival are very important. In this example, all birds are marked using leg bands and some of them receive radios.     

Tree fallows: A comparison between five tropical tree species

The natural abundance of ¹⁵N and ¹³C, conventional soil analyses, and biomass production by maize were used to study the influence of five tropical tree species on soils and their fertility. The experiment was conducted in Morogoro, Tanzania, to compare Cassia (Senna) siamea, Eucalyptus camaldulensis, E. tereticornis (all non-N₂-fixing), Leucaena leucocephala, Prosopis chilensis (both N₂-fixing), and a grass fallow. Maize biomass production, which was correlated with N uptake (P=0.001), was higher on soils from plots with 5-year-old Leucaena and Prosopis spp. compared to the grass fallow, while other tree species had less favourable effects on maize growth. The per cent N was higher in soil and ¹⁵N of soil total N was lower under Prosopis sp. compared to soil under other tree species, which suggests an input from N₂ fixation by Prosopis sp. A transfer of fixed N to maize or to understorey grass species was, however, not indicated by the ¹⁵N natural abundance. Prosopis sp. contributed more C to the soil than the other four tree species; the difference in ¹³C between soils from Prosopis sp. plots and from grass fallow plots showed that the tree contributed 11% to the total C of the soil over a period of 8 years. The leaves of the N₂-fixing species had a low ratio of lignin+phenols to N, and maize growth was negatively correlated with this parameter. The Eucalyptus spp. had leaves with a high lignin+phenols to N ratio, contributed very little C to the soil, and lowered the soil pH.     

A pot study investigating the relationship between tree mulch decomposition and nutrient element availability

Abstract

Studies of the relationship of tree mulch decomposition, nutrient element release and uptake by beans (Phaseolus vulgaris L.) were conducted in excavated compartments. Treatments consisted of single and mixed species combinations of freshly cut biomass additions from the following tropical leguminous trees: 1) Calliandra calothrysus, 2) Gliricidia sepium, 3) Inga edulis, 4) Inga edulis and Calliandra calothrysus, and 5) Inga edulis and Gliricidia sepium. We measured resin‐extractable phosphorus (P), mineral nitrogen (N), nutrient uptake by beans, and bean biomass during sequential harvesting. The Calliandra treatment had significantly higher bean biomass by day 34 with greater P uptake. This was most strongly correlated to resin‐extractable P that showed significant difference in the Calliandra treatment by Day 19. Comparisons with field studies showed similar trends.     

Net protein ratio data: AACC-ASTM collaborative study

Seven- and 14-day net protein ratio (NPR) data were obtained from 7 laboratories for 6 protein sources: ANRC casein, lean beef, lactalbumin, textured vegetable protein, and peanut flour were fed as 10% protein (N X 6.25) in the test diet. Wheat flour, casein, and textured vegetable protein were fed as 6% protein (N X 6.25) in the test diet. Weighed dry ingredients for each diet were sent to each collaborator , who mixed the dry ingredients, then added specified amounts of corn oil and water and mixed each complete diet thoroughly. Rats were adapted for 0, 2, or 4 days, and then were fed the test diets for 28 days for protein efficiency ratio (PER) diets. The animal weight gain and feed consumption data obtained after 7 or 14 days of feeding were used to calculate NPR values. Analyses of data were done before [net protein ratio (NPR)] and after (R-NPR [relative-NPR]) adjustment of the data from each laboratory by its results for the reference protein casein. From the analysis of variance for NPR, significant (P less than 0.05) interactions were observed among laboratories, protein sources, and adaptation times of the animals (0, 2, or 4 days). Inter- and intralaboratory variability were decreased by use of 14-day values compared with 7-day values. Adjustment of the NPR data to R-NPR did not lower the intralaboratory variability but did lower the interlaboratory variability of the data. Increasing adaptation time did not consistently decrease interlaboratory or intralaboratory variability or decrease coefficients of variation (CV) of R-NPR values.(ABSTRACT TRUNCATED AT 250 WORDS)     

树木提取液对白蚁的忌避活性初探

选取并制备83种树木提取液对白蚁进行忌避活性测定结果表明,其中有2 9种树木提取液药后2 4h未见白蚁进入处理室,并结合植物资源和成本等因素初选出18种忌避活性效果较好的树木提取液(室温贮藏期1年)用于复筛试验,最终筛选出对白蚁忌避活性效果较好的山苍子叶和樟树叶树木提取液,可用于研制防蚁新药剂;而对白蚁忌避活性较弱的树木提取液,可结合其对白蚁杀虫活性抑制效果,从中优选出较好树木提取液,用于研制灭蚁新药剂     

Two latent variable risk assessment approaches for mixed continuous and discrete outcomes from developmental toxicity data

Measurements of both continuous and discrete outcomes are encountered in many statistical problems. Here we consider the particular context of teratology studies, where quantitative risk asessment is aimed at determining the effect of dose on the probability that an individual fetus is malformed or of low birth weight, both being important measures of teratogenicity. We will introduce two different joint marginal mean models for outcomes of a mixed nature. First, we propose the Plackett-Dale approach, where for each binary outcome it is assumed that there exists an underlying glatent variable. The latent malformation outcomes are then assumed to follow a Plackett distribution. The second approach we consider is a probit approach. Here it is assumed that there exists an underlying continuous variable for each binary outcome, so the joint distribution for weight and malformation can be assumed to follow a multivariate normal distribution. In both cases, specification of the full distribution will be avoided using pseudolikelihood and generalized estimating equations methodology, respectively. Quantitative risk assessment is illustrated using data from two developmental toxicology experiments.     

Tropical tree community shifts: Implications for wildlife conservation

In tropical forest systems tree community change after initial succession (approximately 50-100 years) is very difficult to detect because of the very slow pace of transformation. Since the mid 1980s, there has been an accumulation of evidence that many forests traditionally considered old growth or mature forests have been disturbed. Using 18 years of data on forest change in Kibale National Park, Uganda, we tested the following hypotheses. Species that frequently recruit only into areas of large-scale disturbance (e.g., conversion to agriculture) (1) have a more strongly negative annualized rate of population change (i.e., recruitment is less than mortality) than trees recruiting into the understory or canopy treefall gaps and (2) these species are declining in their average cumulative diameter at breast height (DBH). Both hypotheses were verified. We then examined relationships between forest change and diets of the five diurnal primates in Kibale. The emergent patterns suggest that forest change will lead to declines in some species, particularly the black-and-white colobus (Colobus guereza). We concluded that what was considered mature forest in Kibale has actually been disturbed in the recent past, and we discuss how potential sources of disturbance (dry-periods, elephant population fluctuations, and human disturbance) may affect both forest change and animal populations. We assess how such information might be useful in forest management.     

Small farm production in dominica,West Indies: A strategy for survival

Calls for sustainable development have emerged largely because of the failure of technology-focused, production-orientated development policies to address the acute rural poverty and deteriorating environments of much of the Third World. Increased agricultural production through greater commercialization has a mirror image of decreasing incomes for the rural poor as market penetration undermines the viability of traditional production systems. These production systems are geared to minimizing risk through the harnessing of the full range of local resources, both private and communal, to produce goods for both the market and home consumption. The need for policies which strengthen traditional production systems is argued through a detailed case study of Dominica, in the Caribbean. The complexity and diversity of what is often considered a single-crop (bananas) agricultural system is demonstrated by looking at a number of localities in different parts of the Island. The example of Dominica is used to argue for policies which, in the words of Robert Chambers, (1983), … ‘put the last first’. Such policies should strengthen existing diversity in the agricultural system through initiatives which give local farmers greater control over the planning and implementation of interventions. The sophistication of local technical knowledge is stressed, as is the need to integrate this knowledge with the technical expertise of outside professionals.     

The use of lysimeter data for the test of two soil–water balance models: A case study

Two soil–water balance models were tested by a comparison of simulated with measured daily rates of actual evapotranspiration, soil water storage, groundwater recharge, and capillary rise. These rates were obtained from twelve weighable lysimeters with three different soils and two different lower boundary conditions for the time period from January 1, 1996 to December 31, 1998. In that period, grass vegetation was grown on all lysimeters. These lysimeters are located in Berlin‐Dahlem, Germany. One model calculated the soil water balance using the Richards equation. The other one used a capacitance approach. Both models used the same modified Penman formula for the estimation of potential evapotranspiration and the same simple empirical vegetation model for the calculation of transpiration, interception, and evaporation. The comparisons of simulated with measured model outputs were analyzed using the modeling‐efficiency index IA and the root mean squared error RMSE. At some lysimeters, the uncalibrated application of both models led to an underestimation of cumulative and annual rates of groundwater recharge and capillary rise, despite a good simulation quality in terms of IA and RMSE. A calibration of soil‐hydraulic and vegetation parameters such as maximum rooting depth resulted in a better fit between simulated and observed cumulative and annual rates of groundwater recharge and capillary rise, but in some cases also decreased the simulation quality of both models in terms of IA and RMSE. The results of this calibration indicated that, in addition to a precise determination of the soil water‐retention functions, vegetation parameters such as rooting depth should also be observed. Without such information, the rooting depth is a calibration parameter. However, in some cases, the uncalibrated application of both models also led to an acceptable fit between measured and simulated model outputs.     

Carbon mineralization of tree leaf litter and crop residues from poplar-based agroforestry systems in Northeast China: A laboratory study

Tree leaf litter and crop residues (fine roots and straw) of the two main crops (maize and peanut) collected from temperate poplar-based agroforestry systems in Liaoning Province, China, were used in a laboratory decomposition experiment. The objectives were to assess the decomposition dynamics of individual plant residues of varying quality and to examine whether interactive effects between poplar litter and crop residues exist during decomposition. Rates of residue decomposition were measured as CO₂ production. Peanut roots decomposed faster than the other individual residues due to their high N and P concentrations and low C/N ratio. There were additive effects between poplar litter and crop residues during decomposition, even though significant differences existed in the initial nutrient concentrations of residues. Our results suggest that legume crops can produce high quality residues and thus have the potential to promote nutrient cycling. Therefore, legume crops have an advantage over other crops for intercropping in temperate agroforestry systems from the viewpoint of sustaining soil fertility.