scholarly journals Species composition and biodiversity indexes of weeds in paddy rice on two sides of dike system during three crops in an Giang Province, Vietnam

2021 ◽  
Vol 42 (3(SI)) ◽  
pp. 895-902
Author(s):  
M.D. Quan ◽  
◽  
T.T. Hang ◽  
S.T. Nam ◽  
◽  
...  
Keyword(s):  
Species Composition ◽  
Similarity Index ◽  
Paddy Rice ◽  
Occurrence Frequency ◽  
Outer Side ◽  
Weed Species ◽  
Biodiversity Indices ◽  
And Control ◽  
Two Sides ◽  
Scientific Name

Aim: This study was conducted to provide data on weed species composition and biodiversity indexes at different rice crops inside and outside of the dike system in An Giang province, Vietnam. Methodology: Weeds were collected from paddy rice of inner and outer side of dike system from six districts of An Giang province, Vietnam. From each sampling sites, two quadrats with 100 m2 (10 m × 10 m) per quadrat were selected to collect weed after 75-80 days of rice planting. Weeds were collected and identified for their scientific name, and the number of each species was defined, followed by calculation of the occurrence frequency and density of samples. Biodiversity indices viz. Shannon-Weaver (H’), Simpson (1- λ), Margalef (d), and similarity index were also studied among three crops and two sides of dike system. Results: The weed composition in the paddy rice in An Giang was diversity with 137 species. Among them, the most species belonged to families Poaceae, Cyperaceae, and Compositae. The species composition of Crop 3 was the highest one. Species occurrence frequency and weed density of groups C, D, E reached the highest value in Crop 1, followed by Crop 2 and 3. The biodiversity indices of weed species composition in the studied sites were high, reaching the highest value in Crop 3. Interpretation: The results of this study enhance the knowledge of weed species composition and biodiversity indexes to effectively manage and control weeds in rice cultivation.

scholarly journals Weed infestation of a cereal-legume mixture depending on its concentration and position in a crop rotation

2012 ◽  
Vol 65 (3) ◽  
pp. 99-108
Author(s):  
Marta K. Kostrzewska ◽  
Maria Wanic ◽  
Magdalena Jastrzębska
Keyword(s):  
Species Composition ◽  
Crop Rotation ◽  
Spring Barley ◽  
Similarity Index ◽  
Floristic Composition ◽  
Field Pea ◽  
Total Biomass ◽  
Weed Species ◽  
Weed Communities ◽  
Weed Infestation

A field study was carried out in the period 2000-2006 at the Experimental Station in Tomaszkowo belonging to the University of Warmia and Mazury in Olsztyn. Its aim was to compare weed infestation of a mixture of spring barley and field pea grown in a four crop rotation with different crop selection and sequence. Each year during tillering of spring barley and before the harvest of the mixture, weed species composition and density were evaluated, while additionally weed biomass was also estimated before the harvest. These results were used to determine species constancy, Simpson&rsquo;s dominance index, the Shannon-Wiener diversity and evenness indices as well as the community similarity index based on floristic richness, numbers and biomass of particular weed species. The cropping frequency and the position of the mixture in the crop rotation did not differentiate the species composition and total biomass of weed communities in the cereal-legume mixture crops. The crop rotation in which the mixture constituted 50% and was grown after itself had a reducing effect on weed numbers. Growing field pea in the 4-year crop rotation promoted weed infestation of the mixture and the dominance of weed communities. <em>Capsella bursa-pastoris</em>, <em>Chenopodium album</em>, <em>Echinochloa crus-galli</em>, <em>Elymus repens</em>, <em>Polygonum convolvulus</em>, and <em>Sonchus arvensis </em>were constant components of the agrophytocenoses. The weed communities were more similar in terms of their floristic composition than in terms of weed density and air-dry weight of weeds.

Carabidae of Barnaul city parks: ecological characteristics and species composition

2018 ◽  
Vol 8 (2) ◽  
pp. 348-353
Author(s):  
E. A. Kuchina ◽  
N. D. Ovcharenko ◽  
L. D. Vasileva
Keyword(s):  
Species Composition ◽  
Diversity Index ◽  
Similarity Index ◽  
Life Forms ◽  
Ground Beetles ◽  
Forest Steppe ◽  
Ecological Groups ◽  
Dominant Group ◽  
Species Diversity Index ◽  
Steppe Species

<p>Anthropogenic impact on the population of ground beetles leads to a change in their numbers, structure of dominance, density, species composition, spectrum of life forms. This makes the beetles Carabidae a convenient and informative bioindicator of the ecological state of biocenoses. The material for this work was the Carabidae collections conducted in June-August 2016-2017 in the park zone of different regions of Barnaul, differing in location, area, hydrological regime, vegetation cover, purpose and anthropogenic load. When processing the material, the quantitative, species and generic composition of the carabidae was determined, calculations were made for such indicators as the Berger-Parker dominance index, the Shannon species diversity index (Hs), and the Jacquard species similarity index. The fauna (Coleoptera, Carabidae) of the park zone of Barnaul is represented by 55 species belonging to 20 genera. The dominant group is represented by species belonging to steppe, forest and polyzonal groups. Forest-steppe species of ground beetles as dominants have not been identified in any of the investigated territories. The greatest variety of ecological groups was noted on the territory of the Yubileyny рark, which is explained by the presence of zones with various microclimatic conditions, the presence of a birch grove that flows through the park with the Pivovarka River, and a wide log in the park. Registered species belong to eight groups of life forms belonging to two classes - zoophagous and myxophytophagous. On the numerical and species abundance, zoophages predominate. The spectrum of life forms corresponds to the zonal spectrum characteristic of the forest-steppe zone.</p><p> </p>

Flat-cutting loosening in the system of fallow cultivation of chernozem soil and weediness of crops

2017 ◽  
Vol 1 (92) ◽  
pp. 78-84
Author(s):  
G. Koval ◽  
M. Kaliyevskiy ◽  
V. Yeshchenko ◽  
I. Martyniuk ◽  
N. Martyniuk
Keyword(s):  
Species Composition ◽  
Crop Rotation ◽  
Field Experiments ◽  
Early Spring ◽  
Weed Species ◽  
Wild Mustard ◽  
Spring Crop ◽  
White Campion ◽  
Investigation Methods ◽  
Top Soil

The article presents the results of field experiments, where on the basis of podsolized heavy loamy chernozem the influence of replacement of mouldboard ploughing with nonmouldboard cultivation over top soil weediness, weediness at the beginning and end of spring crop vegetation and weed species composition before harve sting were studied. Investigation methods of main fall ploughing under spring crops of five-course rotation: soybeans–rape–wheat–flax–barley at the depths of 15-17, 20-22, 25-27 cm were conducted after post-harvest field tillage. Analysis of data on contamination of the top soil with weed seeds have shown that with the replacement of fall main mouldboard ploughing gwith nonmouldboard cultivation the figure before sowing of all crops withdifferent tillage depthat crop rotation average increased by 131-132%. It caused the increase of actual weed infestation of all crops and at the beginning and end of spring crop vegetationafter different depths of fall nonmouldboard cultivation compared with ploughing at crop rotation average it was 120–132 and 123-138%respectively. Species composition of weeds afterthe replacement of main fall mouldboard ploughing with nonmouldboard cultivation remained mainlyunchanged; although in rape plantings the proportion of white campion and early spring weed sincreased, in wheat plantings– wild mustard andscentless mayweed, insoybean plantings– late spring weeds, in flax plantings– white campion, and in barley plantings– scarlet pimpernel.

scholarly journals INVERTEBRATE SPECIES COMPOSITION (Invertebrata) PESTS OF AGROCENOSES OF WHITE CLOVER (Trifolium repens L.) AND THE RELEVANCE OF PROTECTIVE MEASURES

2021 ◽  
Vol 2021 (2) ◽  
pp. 57-80
Author(s):  
Vladimir Zolotarev
Keyword(s):  
Species Composition ◽  
White Clover ◽  
Climatic Conditions ◽  
Agricultural Landscapes ◽  
Economic Losses ◽  
Monitoring And Control ◽  
Protective Measures ◽  
Invertebrate Animal ◽  
Seed Crops ◽  
And Control

The area of natural growth and the scale of economic use of white clover among perennial legumes are spatially one of the most global. Due to the constant presence of wild white clover in many natural phyto-cenoses of most agricultural landscapes of different geographical zones, a certain complex of phytophages has evolved from various classes of invertebrate animal organisms that feed on various parts of this plant and reproduce on it. With the introduction of white clover into the culture and the spread of production crops of this plant over large areas, more favorable conditions are created for uncontrolled mass re-production of pests, which can cause already economically and economically significant crop losses. White clover is affected by multi-eating and specialized pests, the damage from which is determined by their biological characteristics and climatic conditions. The high population of white clover crops with a complex of herbivorous invertebrates implies constant monitoring and control of the species composition of the harmful fauna of white clover crops in order to organize, if necessary, protective measures against them. This issue is especially relevant for seed crops. The main pests of seed stands are considered to be weevils of the genera Apion Herbs., Phytonomus Herbs., Sitona Germar., Hypera Germar., which can re-duce seed yield by 50% or more. To reduce the economic losses of the crop on white clover, an integrated protection system should be implemented using chemical, biological and agrotechnical pest control meas-ures based on taking into account their economic harmfulness thresholds. One of the important directions of increasing the efficiency of the production use of white clover is the development of varieties of this crop that are resistant to damage by pathogenic organisms and pests.

scholarly journals Mobile Application Development for Spectral Signature of Weed Species in Rice Farming

2021 ◽  
Vol 29 (4) ◽  
Author(s):  
Nor Athirah Roslin ◽  
Nik Norasma Che’Ya ◽  
Nursyazyla Sulaiman ◽  
Lutfi Amir Nor Alahyadi ◽  
Mohd Razi Ismail
Keyword(s):  
Mobile Application ◽  
Near Infrared ◽  
Spectral Signature ◽  
Weed Species ◽  
Application Development ◽  
Spectral Signatures ◽  
Weed Infestation ◽  
Access Information ◽  
Master Builder ◽  
And Control

Weed infestation happens when there is intense competition between rice and weeds for light, nutrients and water. These conditions need to be monitored and controlled to lower the growth of weeds as they affected crops production. The characteristics of weeds and rice are challenging to differentiate macroscopically. However, information can be acquired using a spectral signature graph. Hence, this study emphasises using the spectral signature of weed species and rice in a rice field. The study aims to generate a spectral signature graph of weeds in rice fields and develop a mobile application for the spectral signature of weeds. Six weeds were identified in Ladang Merdeka using Fieldspec HandHeld 2 Spectroradiometer. All the spectral signatures were stored in a spectral database using Apps Master Builder, viewed using smartphones. The results from the spectral signature graph show that the jungle rice (Echinochloa spp.) has the highest near-infrared (NIR) reflectance. In contrast, the saromacca grass (Ischaemum rugosum) shows the lowest NIR reflectance. Then, the first derivative (FD) analysis was run to visualise the separation of each species, and the 710 nm to 750 nm region shows the highest separation. It shows that the weed species can be identified using spectral signature by FD analysis with accurate separation. The mobile application was developed to provide information about the weeds and control methods to the users. Users can access information regarding weeds and take action based on the recommendations of the mobile application.

scholarly journals Peculiarities of distribution of unseeded species in crops of perennial grasses, depending on the composition of the grass mixture and the mode of use of the grass

2018 ◽  
pp. 120-127
Author(s):  
V. Olifirovich
Keyword(s):  
Species Composition ◽  
Perennial Grasses ◽  
Weed Species ◽  
Grass Stand ◽  
Weed Infestation

The article investigated the species composition and dynamics of changes in the contamination of agrophytocenoses of perennial grasses, depending on the composition of the grass mixture and the mode of use of the grass stand. In the crops of perennial grasses, 34 weed species belonging to 12 botanical kind were found in the first three years of use of the grass stand. In the structure of weed infestation of perennial grasses, the species of the Astra kind of weeds dominated, which were represented by stanktis annual, dandelion, yarrow, field thistle.

scholarly journals THE EFFECT OF GRASSLAND MANAGEMENT ON DIVERSITY OF SPIDER ASSEMBLAGES IN THE MÁTRA MOUNTAIN

2016 ◽  
Vol 7 ◽  
pp. 291-297
Author(s):  
Tünde Szmatona-Túri ◽  
Diána Vona-Túri
Keyword(s):  
Nature Conservation ◽  
Conservation Management ◽  
Similarity Index ◽  
Grassland Management ◽  
Hay Meadows ◽  
Mountain Grasslands ◽  
Spider Communities ◽  
Study Sites ◽  
And Control ◽  
The Relationship

Our investigation targeted the diversity of spider communities of meadows under nature conservation management and the relationship between mowing and the spider diversity. The study sites represented by six grasslands on three localities of Mátra mountain of Hungary. All three localities were contained a hay meadow and a not mowed meadow. Hay meadows had the richest spider communities.  In the control habitats, the equitability and the Shannon-Wiener diversity were lower than in the mowed grasslands. According to the Bray-Curtis similarity index significant differences were observed between spider assemblages of mowed and control habitats. The prevention of succession effects so rich structure of the vegetation where diverse spider communities can live. Our results suggest that mowing is a suitable management for maintaining a high biodiversity in mountain grasslands.

scholarly journals KOMUNITAS MAKRO ALGA DI PERAIRAN PANTAI ERI TELUK AMBON

2019 ◽  
Vol 15 (1) ◽  
pp. 40-45
Author(s):  
Frijona F Lokollo
Keyword(s):  
Community Structure ◽  
Species Composition ◽  
Relative Frequency ◽  
Occurrence Frequency ◽  
Frequency Of Occurrence ◽  
Gracilaria Salicornia ◽  
Turbinaria Ornata ◽  
Belt Transect ◽  
Macro Algae

This research was conducted in Eri Beach, Ambon Bay on November 2016 to study community structure which consist of species composition, density and occurrence frequency of macro algae.  Sample of macro algae was collected by using belt transect method.  The results showed that there were 11 species of macro algae in the area which were belonged to 11 genera, 9 families, 8 orders, 3 classes and 3 divisions. Those species were Halimeda opuntia and Caulerpa serrulata (Chlorophyta), Padina minor and Turbinaria ornata (Phaeophya), Amphiroa rigida, Galaxaura rugosa, Ceratodictyon spongiosum, Gracilaria Salicornia, Laurencia papillosa, Acanthophora muscoides and Halymenia durvillaei (Rhodophyta). The highest density was represented by Amphiroa rigida (2.02 ind/m2) while the highest relative frequency of occurrence belonged to Padina minor (27%). Keywords : Community, macro algae, density, Eri, Ambon Bay   ABSTRAK Penelitian ini bertujuan untuk mengetahui struktur komunitas makro alga meliputi komposisi jenis, frekuensi kehadiran serta kepadatan di Pantai Eri. Penelitian dilakukan pada bulan November 2016. Stasiun pengamatan makro alga yaitu di perairan pantai Eri. Metode sampling menggunakan Belt Transect. Hasil penelitian ditemukan 11 spesies, 11 genus, 9 famili, 8 ordo, 3 kelas dan 3 devisi. Chlorophyta terdiri dari Halimeda opuntia dan Caulerpa serrulata. Phaeophya terdiri dari Padina minor dan Turbinaria ornata. Rhodophyta terdiri dari Amphiroa rigida, Galaxaura rugosa, Ceratodictyon spongiosum, Gracilaria Salicornia, Laurencia papillosa, Acanthophora muscoides dan Halymenia durvillaei. Kepadatan jenis tertinggi spesies A. rigida (2.02 ind/m2) dan frekuensi kehadiran relatif tertinggi spesies Padina minor (27%).

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