Ant diversity and abundance in pasture system and two agricultural land uses in the Rashad district, Southern Sudan

The most common ecological consequence of biodiversity loss is a reduction in ecosystem functions. These responses, however, vary depending on the type of land-use change and the ecological setting. This study investigated the impact of land-use type and ecosystem functions on the ant assemblage of Rashad district, Sudan. Therefore, the purposes of this study are to evaluate the composition and structure of the ant assembly in the station, as well as to determine the trophic guilds and functional groups and their spatial variation in three different land uses. Furthermore, based on the type of land use to determine how the conversion of native vegetation affects the richness and composition of ant species. In each location, we sampled three 20-meter-long transects (Sample plot). Each sample plot consisted of a grid of 12 pitfall traps arranged in three rows of four traps each, with a 2 m spacing between them, replicated six times in a single year. We collected 38 ant species from four subfamilies and 17 genera. Parasyscia lamborni was the most abundant species followed by Bothroponera crassa. Ant diversity was higher in Soy monoculture and Organic farming than in the Pasture. The frequency distributions of ant Functional groups in Soy monoculture and Organic farming were significantly different from the frequency distributions in the pasture. The omnivorous and predator’s trophic guilds were the best represented and regarding functional groups. We found a high proportion of tropical climate specialists and Myrmicinae generalists. These findings suggest that Pasture Activation reduces ant diversity. It can also help to increase the population of species with a diverse diet that predominate in areas where stress and disturbance prevent other ants from reproducing.

Productivity of Pangi (Pangium edule Reinw.) and biodiversity of agroforestry systems at various altitudes in Toraja Regency, South Sulawesi

There are two important things that farmers consider in selecting and developing plant species in their agroforestry system, namely productivity and suitability to the site. This study aims to determine the productivity of the pangi crop and the biodiversity of the agroforestry system at different altitudes. This research was conducted from June to November 2018 at three different altitudes, namely in Lembang Palesan (Rembon District) which represents an altitude of <600 m above sea level, Lembang Turunan (Sangalla District) which represents an altitude of 800-850 m above sea level, and Lembang Gasing (Mengkendek District) which represents an altitude of > 1000 m above sea level. The research method used is a survey method with the placement of sample plots by Purposive Sampling. The sample plot size is 20m x 50m or 0.1 ha. At each different altitude, 10 sample plots were made, so the number of sample plots was 30. The parameters measured were pangi fruit production, tree diameter and height and recorded all plant species in the sample plot. Data analysis was carried out quantitatively and descriptively, while agroforestry system plant species diversity was identified using vegetation analysis methods. The results showed that the fruit production of the pangi plant, density, LBDS and diameter of the pangi tree were significantly different at each different altitude and the largest was at an altitude of 800-850 m above sea level, but the number of plant species and the diversity of plant species at each altitude were relatively the same in the medium category, as well as the density of all types of plants, and the average height of pangi trees were not significantly different at each different altitude. Thus, it is not recommended that pangi crop be developed at an altitude above 850 m above sea level.

Elongated sample plot shapes produce higher measurement precision in clustering populations

Monitoring the density of natural populations is crucial for ecosystem management decision making and natural resource management. The most widely used method to measure the population density of animal and plant species in natural habitats is to count organisms in sample plots. Yet evaluation of survey performance by different sample plot shapes, e.g. quadrats compared with transects, has been largely neglected since the 1990s and has not been undertaken using simulation. Simulating populations and surveys, we evaluated population density measurement precision for 900 cases, testing 30 sample plot survey designs in each of 30 spatially clustered populations. We varied three design options: elongation of plot shape while keeping sample area constant, systematic or random plot allocation, and sample size. Survey design performance varied markedly: elongating the plot shape always improved survey precision; allocating plots systematically sometimes did. (i) Averaged across all tested populations, elongated (1:100) transect plot shapes were 2-to-3 times more precise than square (10:10) quadrats. (ii) The precision of systematic surveys accelerated with sample plot number, increasing faster than the (known) linear increase under simple random sampling. This non-linear, concave upward, dependence of systematic precision on sample size has not previously been reported. (iii) The most precise design we evaluated used long narrow transects allocated systematically. Averaging among all 30 tested populations, a researcher would need 600 random square (10:10) quadrats to equal the precision achieved by 100 systematic (1:100) transects. Finding this average efficiency difference of 600% for a survey sample size of 100 plots, these simulation results imply that field trips requiring five sampling days using random quadrats could achieve equal precision in one or two days using systematic elongated transects. For all clustered populations we tested, long narrow transects resulted in a more efficient design for sample plot survey.

Tebang Pilih Mengubah Keanekaragaman Semut Tanah Hutan di Kalimantan Timur, Indonesia

This study assesses the short-term effects of selective cutting on the diversity of ground ants (Hymenoptera: Formicidae) in the secondary rainforest. Ground ants were collected using a pitfall trap in a circular sample plot of 0.5 ha. A total of nine sample plots were randomly placed in a 98-ha cutting compartment. Fifteen pitfall traps were planted in each circular plot. A total of 135 pitfall traps were established in the cutting compartment. The average cutting intensity of 8 trees/haas applied in the cutting compartment. Insect sampling and measurement of environmental factors were carried before cutting and two days after cutting. In this study, the abundance, diversity, species richness, and evenness index of ground ants before cutting compared to after cutting. The results of this study indicated that the short-term impact of selective cutting on ground ants was varied. Selective cutting may increase or decrease the abundance and morphospecies composition of ground ants. The abundance of forager and ground-dwelling omnivores increased after selective cutting, whereas for the predator, scavenger, and seed disperser ants were decreased after selective cutting. Keywords: biodiversity, forest conservation, ground ant, selective cutting

Tree Diversity In Bufferzone Area at Sikulaping Protected Forest, Pakpak Bharat District, Indonesia

This research was conducted at protected forest Sikulaping, Pakpak Bharat Regency, North Sumatra. Data collection and processing were carried out in October - November 2019 using a purposive sampling method, by creating 3 sample plots at each location which is a buffer zone for the Sikukaping protected forest, the village namely Aornakan1, Kuta Tinggi and Sibongkaras. Observations were made on the sample plot with a size of 1000 meters by observing the 20 meters right and left of the plots. The results of this study showed that the number of trees varied for 3 buffer villages, Aornakan 1 Village, found a total of 41 individuals from 16 species with Palaqium gutta as the highest species found with 10 individuals and Species Important Value (41,450). As for Kutatinggi village, there are 22 individuals from 15 species and Shorea parvifolia were found 2 individuals with NPJ 19,008 along with 6 other species Durio zibethinus, Adinandra dumosa, Lithocarpus gracilis, Syzygium polyanthum, Tristianopsi whietena and Uncaria glabra. Whereas in Sibongkaras village, 30 individuals were found from 24 species with Styrax benzoid as the most common species with 4 individuals and NPJ 26,650. Tree diversity (H ') found in the villages of Aornakan, Kuta Tinggi are moderate criteria, by index 2.35, 2.64, while Sibongkaras with an index of 3.07 includes high diversity. The results of this diversity show that the Sikulaping protected forest has a good level of tree productivity and the condition of the forest is still maintained

Effects of Sample Plot Size and Prediction Models on Diameter Distribution Recovery

Distribution of tree diameters in a stand is characterized using models that predict diameter moments and/or percentiles in conjunction with a mathematical system to recover the parameters of an assumed statistical distribution. Studies have compared Weibull diameter distribution recovery systems but arrived at different conclusions regarding the best approach for recovering a stand’s diameter distribution from predicted stand-level statistics. We assessed the effects of sample plot size and diameter moments/percentiles prediction models on the accuracy of three approaches used in recovering Weibull distribution parameters—method of moments, percentile method, and moments-percentile hybrid method. Data from five plot sizes, four of which were virtually created from existing larger plots, from unthinned loblolly pine (Pinus taeda) plantations, were used to fit moments/percentile prediction models and to evaluate the accuracy of the diameter distribution recovered using three approaches. Both plot size and prediction model form affected the accuracy of the recovery approaches as indicated by the changes in their ranking from one plot size to another for the same model form. The method of moments approach ranked best when the evaluation error index did not account for tree stumpage value, but the moments-percentile hybrid approach ranked best when stumpage value was considered. Study Implications Diameter distribution recovery techniques make it possible to disaggregate trees per unit area, predicted by the whole stand growth and yield models, into diameter and utilization product classes. Thus, the techniques provide insights into stand structure, which can guide management decisions such as thinning and selection harvesting. The techniques are also used to generate yield tables by product class, which are important inputs into harvest scheduling optimization programs. An accurate diameter recovery technique is therefore critical to forest management and planning. Based on the findings of this study, the best approach of developing a diameter distribution recovery system for unthinned loblolly pine plantations would be to use the hybrid approach, with tree diameter data collected from plots of at least one-tenth hectare. The well-known (and, most likely, widely used) method of moments approach may not be the best choice. For predicting stand diameter moments and order statistics used in a diameter distribution recovery system, it would be best to use a linear additive model that incorporates a measure of stand density, such as relative spacing and/or number of trees per unit area, and a measure of the stand’s stage of development, such as dominant height and/or age.

Flora of Seed Plants in Longquan Mountain, Wuhan

In recent years, in order to provide theoretical and scientific basis for the protection and rational utilization of plant resources in Lon longquan mountain gquan Mountain, the seed plants in Longquan Mountain were taken as the research object, and the field investigation was carried out by using the method of line plus typical sample plot, so as to further study the characteristics of investigated area were further studied. The results show: There are 231 species of 191 genus in 90 families, including 5 families, 9 genus and 11 species of gymnosperms, and 82 species of 182 genus and 85 species of angiosperms. The 14 distribution types of seed plants belong to the statistics: North temperate distribution There are 72 genus, accounting for 37.7% of the total genus of the area, reflecting the obvious north temperate nature of the flora. In addition, there are many ancient taxa and Cretaceous and Tertiary relict plants. There are 163 genus of single genus and genus genus, accounting for 85.3% of the total genus of the region, indicating that the plant origin is relatively old, there are 7 genus in China, which indicates that the unique phenomenon exists, but it is not obvious.

Forest Tree Composition: A Comparative Study of Timber Species in Bayelsa State Nigeria

Measuring tree species diversity is critical for forest management, particularly where timber species suffer undue anthropogenic pressure. This study was carried out in Bayelsa State, Nigeria. A sample plot was systematically chosen from randomly selected communities in each of the three senatorial districts Bayelsa West (BW), Bayelsa East (BE) and Bayelsa Central (BC) of the State. Each sample plots measured 25 m x 25 m and all timber tree species that were at least six feet above ground level within each sample plot were identified, counted and measured. Fifty individual timbers were encountered in the sample plot at Ogobiri community in BW, fifty-two at Kolo 1 community in BE and fifty-six at Gbarain community in BC belonged to 18, 16 and 14 different families respectively. Families with the largest number of species in the plots were Gentianaceae and Meliaceae, and the highest diversity indices were recorded from BE senatorial district. Generally, the basal area of the sample plots increases with an increase in diameter at breast height. The forested zones were on flat terrain characterized by seasonal flood inundation, and the similarities of timber species in the plots occurred as (BW-BC)> (BW-BE)> (BC-BE). Also, four tree species Coelocaryon preussii, Sacoglottis gabonensis, Milicia excelsa and Triplochiton scleroxylon were identified as rare species, and management options that would ensure ad infinitum supply of timber species were proposed.

KEANEKARAGAMAN JENIS CAPUNG (ODONATA) PADA AREAL PERSAWAHAN DI KECAMATAN TABIR DAN DI KECAMATAN PANGKALAN JAMBU KABUPATEN MERANGIN

Penelitian ini bertujuan untuk mengetahui jenis-jenis dan keanekaragaman jenis-jenis capung (odonata) di kawasan sawah Kec. Pangkalan jambu dan Kec. Tabir Kabupaten Merangin. Pengambilan sampel capung dilakukan di Kecamatan Pangkalan Jambu (Desa Bungo Tanjung dan Tanjung Mudo) dan Kecamatan Tabir (Desa Seling dan Desa Kampung Baru) Kabupaten Merangin. Identifikasi capung dilakukan di Laboratorium Universitas Muara Bungo. Penelitian ini dimulai dari tanggal 03 Februari 2019 sampai dengan tanggal 30 April 2019.Penelitian ini berbentuk survei dan metode pengambilan sampel yang digunakan adalah Purposive Random Sampling. Pada tiap kecamatan dipilih dua desa sebagai tempat pengamatan. Pada tiap petak pertanaman ditentukan petak sampel yang berukuran 5 x 5 m secara sistematis pada garis diagonal. Pengambilan sampel Capung di lapangan dilakukan sebanyak 6 kali dengan interval pengambilan sampel dua minggu sekali yang dilakukan dengan dua metode yaitu koleksi secara langsung yaitu menangkap dengan tangan setiap Capung yang ditemukan pada petak sampel dan Metode jaring ayun. Adapun Variabel yang diamati adalah Identifikasi capung, Indeks Keanekaragaman, Indeks Kemerataan Spesies dan Kekayaan Spesies.Hasil penelitian menunjukan bahwa jenis-jenis capung (odonata) pada aeral persawahan di Kecamatan Pangkalan Jambu adalah 12 spesies dan 10 spesies di Kecamatan Tabir dengan rincian 8 spesies yang sama yaitu Crocodemis servilia, Orthetrum chrysis, Orthetrum testaceum, Orthetrum pruinosum, Orthetrum sabina, Diplacodes travilis, Agriocenemis femina, Agriocenemis pygmea, dan 6 spesies yang berbeda Pseudagrio pruinosum, Coriagrio colamineum, Orthetrum glaucum, Potamarcha congener, Libellago lineata dan Copera marginipes. Keanekaragaman jenis-jenis capung (odonata) yang ada di kawasan sawah Kecamatan Pangkalan jambu dan kecamatan Tabir Kabupaten Merangin berada pada tingkat sedang dengan indeks keanekaragaman sebesar 2,03 – 2,15, tingkat kemerataan yang stabil dengan indeks kemerataan 0,86-0,88 serta areal persawahan di kecamatan Pangkalan Jambu memiliki kekayan spesies yang lebih tinggi dibandingkan kawasan sawah kec. Tabir. Kata Kunci :Keanekaragaman, Spesies Capung, Areal Persawahan This study aimed to determine types and diversity of dragonflies species (odonata) in Pangkalan Jambu District and Tabir District Merangin Regency. The sampling of dragonflies was carried out in Pangkalan Jambu District (Bungo Tanjung Village and Tanjung Mudo village) and Tabir District (Sling Village and kampung baruh Village) Merangin Regency. Identification of dragonflies was carried out at the Muara Bungo University Laboratory. This study began from February, 3th to April, 30th 2019.This research takes the form of a survey and kind of the sampling method is Purposive Random Sampling. In each district two villages were chosen as observation sites. In each planting plot, a sample plot of 5 x 5 m was determined systematically on a diagonal line. Dragonfly sampling in the field was carried out as much as 6 times with biweekly sampling intervals which were carried out by two methods, namely direct collection, with catching by hand every dragonfly found in the sample plot and swinging method. The variables observed were dragonfly identification, diversity index, species evenness and species richness index.The results showed that the types of dragonflies (odonata) in rice fields in Pangkalan Jambu district were 12 species and 10 species in Tabir district with details of the same 8 species namely Crocodemis servilia, Orthetrum chrysis, Orthetrum testaceum, Orthetrum pruinosum, Orthetrum sabina, Diplacodes travilis, Agriocenemis femina, Agriocenemis pygmea, and 6 different species of Pseudagrio pruinosum, Coriagrio colamineum, Orthetrum glaucum, Potamarcha congener, Libellago lineata and Copera marginipes. The diversity of dragonfly species (odonata) in the paddy field of Pangkalan jambu district and Tabir district of Merangin Regency is at a moderate level with a diversity index of 2.03 - 2.15, a stable level of evenness with an evenness index of 0.86-0, 88 and rice fields in the Pangkalan Jambu district have higher species richness compared to the rice field area. Keywords: Diversity, Dragonflies, Rice Fields