scholarly journals AVALIAÇÃO DE TÉCNICAS PARA INDUÇÃO DA REGENERAÇÃO NATURAL EM ÁREA DE PRESERVAÇÃO PERMANENTE SOB USO ANTERIOR DO SOLO COM Pinus elliottii

FLORESTA ◽  
2010 ◽  
Vol 40 (2) ◽  
Author(s):  
Lauri Amândio Schorn ◽  
Andres Krieger ◽  
Marmonn Canestraro Nadolny ◽  
Tatiele Anete Bergamo Fenilli
Keyword(s):  
Forest Restoration ◽  
Riparian Forest ◽  
Pinus Elliottii ◽  
Seed Rain ◽  
Ecological Groups ◽  
Higher Plant ◽  
Santa Catarina ◽  
Horizontal Structure ◽  
Plant Densities ◽  
Speed Up

Este trabalho teve como objetivos avaliar os efeitos de diferentes técnicas para indução da regeneração natural em uma área de preservação permanente, após o corte final de um povoamento de Pinus elliottii. O experimento foi instalado em dezembro de 2004, em uma fazenda da empresa Renova Floresta, no município de Rio Negrinho, estado de Santa Catarina. Foram estabelecidos sete tratamentos aplicando técnicas que visam acelerar o processo de restabelecimento da vegetação florestal. Em julho de 2008 foi realizada a amostragem da vegetação arbórea, nas áreas correspondentes aos tratamentos implantados, quando foram mensurados todos os indivíduos maiores que 0,20 m de altura. Foram avaliadas a estrutura horizontal, riqueza, diversidade, participação de grupos ecológicos e distribuição das alturas. Solanum variabile, Baccharis uncinela e Eupatorium compressum foram as espécies de maior frequência, densidade e importância na maioria dos tratamentos aplicados. A aplicação de chuva de sementes, transposição de solo e instalação de poleiros resultaram em densidades mais elevadas de plantas. A riqueza de espécies e a diversidade foram maiores nos tratamentos com plantio de enriquecimento, aplicação de chuva de sementes e instalação de poleiros artificiais. A densidade, diversidade e riqueza de espécies foram consideradas as variáveis mais adequadas para a avaliação da restauração ecológica. Palavras-chave: Regeneração natural; floresta ciliar; restauração florestal.  AbstractEvaluation of techniques for induction of regeneration in permanent preservation areas under former use of the soil with Pinus elliottii. This work aimed at evaluating the effects of seven techniques for natural regenerative induction in an area of permanent preservation, after the final cut of Pinus elliottii stand. The experiment was installed on a farm belonging to Renova Forest Co., in the municipality of Rio Negrinho, State of Santa Catarina on December 2004. Seven treatments were installed using techniques to speed up the forest vegetation restoration. On July 2008 tree sampling was done in the areas corresponding to the seven treatments, with measurement of all individuals higher than 0.20 m. Evaluated aspects were the horizontal structure, richness, diversity, participation and distribution of ecological groups of heights. Solanum variabile, Uncinela Baccharis and Eupatorium compressun were the species of higher frequency, density and size in most treatments. The application of seed rain, soil transposition and the installation of perches resulted in higher plant densities. The richness of species and diversity were higher in treatments with enrichment planting, application of seed rain and installation of artificial perches. The density, diversity and species richness variables have been considered more appropriate for the evaluation of ecological restoration.Keywords: Natural regeneration; riparian forest; forest restoration.

scholarly journals Stand Stability of Pure and Mixed-Eucalyptus Forests of Different Tree Species in a Typhoon-Prone Area

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 458
Author(s):  
Haiyan Deng ◽  
Linlin Shen ◽  
Jiaqi Yang ◽  
Xiaoyong Mo
Keyword(s):  
Tree Species ◽  
Forest Restoration ◽  
Large Scale ◽  
Stand Structure ◽  
Pinus Elliottii ◽  
Stem Form ◽  
Tree Species Composition ◽  
Eucalyptus Plantation ◽  
Mixed Plantation ◽  
Preservation Rate

Background and Objectives: The stable stand structure of mixed plantations is the basis of giving full play to forest ecological function and benefit. However, the monocultural Eucalyptus plantations with large-scale and successive planting that caused ecological problems such as reduced species diversity and loss of soil nutrients have presented to be unstable and vulnerable, especially in typhoon-prone areas. The objective of this study was to evaluate the nonspatial structure difference and the stand stability of pure and mixed-Eucalyptus forests, to find out the best mixed pattern of Eucalyptus forests with the most stability in typhoon-prone areas. Materials and Methods: In this study, we randomly investigated eight plots of 30 m × 30 m in pure and mixed-Eucalyptus (Eucalyptus urophylla S. T. Blake × E. grandis W. Hill) plantations of different tree species (Neolamarckia cadamba (Roxb.) Bosser, Acacia mangium Willd., and Pinus elliottii var. Elliottii Engelm. × P. caribaea Morelet) on growth status, characterized and compared the distribution of nonspatial structure of the monoculture and mixtures, and evaluated the stand quality and stability from eight indexes of the nonspatial structure, including preservation rate, stand density, height, diameter, stem form, degree of stem inclination, tree-species composition, and age structure. Results: Eucalyptus surviving in the mixed plantation of Eucalyptus and A. mangium (EA) and in the mixed plantation of Eucalyptus and P. elliottii × P. caribaea (EP) were 5.0% and 7.6% greater than those in pure Eucalyptus plantation (EE), respectively, while only the stand preservation rate of EA was greater (+2.9%) than that of the pure Eucalyptus plantation. The proportions of all mixtures in the height class greater than 7 m were fewer than that of EE. The proportions of EA and mixed plantation of Eucalyptus and N. cadamba (EN) in the diameter class greater than 7 m were 10.6% and 7.8%, respectively, more than that of EE. EN had the highest ratio of branching visibly (41.0%), EA had the highest ratio of inclined stems (8.1%), and EP had the most straight and complete stem form (68.7%). The stand stability of the mixed plantation of Eucalyptus and A. mangium presented to be optimal, as its subordinate function value (0.76) and state value (ω = 0.61) of real stand were the largest. Conclusions: A. mangium is a superior tree species to mix with Eucalyptus for a more stable stand structure in the early growth stage to approach an evident and immense stability and resistance, which is of great significance for the forest restoration of Eucalyptus in response to extreme climate and forest management.

GRAIN YIELD COMPARISON OF PURE STANDS AND MIXTURES OF DIFFERENT PROPORTIONS FOR TWO HYBRIDS OF MAIZE

1985 ◽  
Vol 65 (3) ◽  
pp. 481-485 ◽  
Author(s):  
G. J. HOEKSTRA ◽  
L. W. KANNENBERG ◽  
B. R. CHRISTIE
Keyword(s):  
Zea Mays ◽  
Grain Yield ◽  
Zea Mays L ◽  
Pure Stand ◽  
Higher Plant ◽  
Data Support ◽  
Plant Densities ◽  
The Difference ◽  
Corn Grain ◽  
Corn Grain Yield

The objective of this study was to determine the effects on grain yield of growing cultivars in mixtures of different proportions. Two maize (Zea mays L.) hybrids, Pride 116 and United 106, were grown for 2 yr in pure stand and in seven mixtures of different proportions (7:1, 6:2, 5:3, 4:4, 3:5, 2:6, 1:7) at plant densities of 61 500, 99 400, and 136 000 plants per hectare. The total number of mixture combinations was 42, i.e. 2 years × three densities × seven proportions. All but one mixture yielded as expected based on the yield of component hybrids in pure stand. The higher yielding hybrid (United 106) yielded significantly less grain per plant in mixtures than in pure stand. The lower yielding hybrid (Pride 116) yielded more in mixtures than in pure stand, although the difference was not significant. These data support previous observations that the ability of a hybrid to yield in pure stands is not necessarily related to its ability to yield in mixtures. High plant densities appear to enhance the likelihood of interactions occurring among hybrids. For United 106, the number of proportions yielding less grain per plant than in pure stand was highly significant at the two higher plant densities. For Pride 116, the number of proportions yielding more than in pure stand was highly significant at the highest plant density.Key words: Corn, grain yield, mixtures of different proportions, high plant densities, Zea mays

scholarly journals Evaluation of Tree Seedling Mortality and Protective Strategies in Riparian Forest Restoration

2008 ◽  
Vol 25 (3) ◽  
pp. 117-123 ◽  
Author(s):  
William S. Keeton
Keyword(s):  
Forest Restoration ◽  
Riparian Forest ◽  
Planting Density ◽  
Tree Seedling ◽  
Seedling Mortality ◽  
Order Stream ◽  
Growing Seasons ◽  
Deer Browse ◽  
Limited Effectiveness ◽  
Protective Strategies

Abstract Riparian forest restoration can be severely constrained by tree seedling mortality. I evaluated the effects of tree shelters and planting density on herbivory and seedling mortality at a restoration site in the Lake Champlain Basin of Vermont. Eighteen experimental units were established along a 5th-order stream and planted with bare-root seedlings of seven species associated with northern hardwood floodplain forests. Two treatments were applied in a factorial design: shelters versus no shelters and high versus low planting density. Mortality and herbivory data were collected over three growing seasons. Survivorship declined to 56.4% after three growing seasons and varied significantly by species. Planting density, presence/absence of shelters, and their interaction had significant effects on survival, browse, or girdling intensity when tested for all species combined. Browse rates were high (44%), whereas girdling rates were low (3.4%). Both browse (P < 0.001) and girdling (P = 0.022) contributed to seedling mortality. High rates of deer browse on seedlings in shelters were due, in part, to the short height (60 cm) of the shelters, suggesting a need for taller shelters. A large portion (39%) of dead seedlings were neither browsed nor girdled, signaling the importance of other mortality agents. An adaptive approach is recommended to compensate for high seedling mortality and the limited effectiveness of protective devices.

scholarly journals Patterns of tillering and grain production of winter wheat at a wide range of plant densities.

1978 ◽  
Vol 26 (4) ◽  
pp. 383-398 ◽  
Author(s):  
A. Darwinkel
Keyword(s):  
Winter Wheat ◽  
Grain Yield ◽  
Harvest Index ◽  
Plant Density ◽  
Fold Increase ◽  
Grain Production ◽  
Higher Plant ◽  
Grain Number ◽  
Wide Range ◽  
Plant Densities

The effect of plant density on the growth and productivity of the various ear-bearing stems of winter wheat was studied in detail to obtain information on the pattern of grain production of crops grown under field conditions. Strong compensation effects were measured: a 160-fold increase in plant density (5-800 plants/m2) finally resulted in a 3-fold increase in grain yield (282 to 850 g DM/m2). Max. grain yield was achieved at 100 plants/m2, which corresponded to 430 ears/m2 and to about 19 000 grains/m2. At higher plant densities more ears and more grains were produced, but grain yield remained constant. Tillering/plant was largely favoured by low plant densities because these allowed tiller formation to continue for a longer period and a greater proportion of tillers produced ears. However, at higher plant densities more tillers/unit area were formed and, despite a higher mortality, more ears were produced. The productivity of individual ears, from main stems as well as from tillers, decreased with increasing plant density and with later emergence of shoots. In the range from 5 to 800 plants/m2 grain yield/ear decreased from 2.40 to 1.14 g DM. At 800 plants/m2 nearly all ears originated from main stems, but with decreasing plant density tillers contributed increasingly to the number of ears. At 5 plants/m2, there were 23 ears/plant and grain yield/ear ranged from 4.20 (main stem) to 1.86 g DM (late-formed stems). Grain number/ear was reduced at higher densities and on younger stems, because there were fewer fertile spikelets and fewer grains in these spikelets. At the low density of 5 plants/m2, plants developed solitarily and grain yield/ear was determined by the number of grains/ear as well as by grain wt. Above 400 ears/m2, in this experiment reached at 100 plants/m2 and more, grain yield/ear depended solely on grain number, because the wt. of grains of the various stems were similar. The harvest index showed a max. of about 44% at a moderate plant density; at this density nearly max. grain yield was achieved. At low plant densities the harvest index decreased from 45% in main stems to about 36% in late-formed stems. However, no differences in harvest index existed between the various ear-bearing stems if the number of ears exceeded 400/m2. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Isolation of entomopathogenic nematodes in the west region of Santa Catarina, Brazil

2020 ◽  
Vol 87 ◽  
Author(s):  
Dannyelle Cristine Orsolin de Morais ◽  
Marco Aurélio Tramontin ◽  
Vanessa Andaló
Keyword(s):  
Entomopathogenic Nematodes ◽  
Riparian Forest ◽  
Lolium Multiflorum ◽  
Soil Samples ◽  
Pennisetum Purpureum ◽  
Native Forest ◽  
Potential Candidate ◽  
Santa Catarina ◽  
Pasture Area ◽  
The City

ABSTRACT: Entomopathogenic nematodes (EPNs) are potential candidate for integrated pest management programs. As little is known about the presence of these organisms in the state of Santa Catarina, it was aimed to perform soil sampling in the cities of Chapecó, Palmitos, Seara and Concordia for the isolation of EPNs. In total, 200 samples (100 g soil) were collected. In Chapecó, 40 samples from soil containing green manure (Raphanus sativus), five samples from native forest area and five samples from riparian forest were collected. In the city of Palmitos, 40 soil samples were obtained in the areas of soybean (Glycine max), corn (Zea mays), oats (Avena strigosa), and pasture (Pennisetum purpureum), and in each location 10 samples were taken. Sixty soil samples were collected in the city of Concordia, in a pasture area (A. strigosa). In Seara, the 50 soil samples were collected at a pasture consortium site between ryegrass (Lolium multiflorum) and black oats (A. strigosa). For the isolation, the collected soil samples were conditioned in 350 mL plastic containers and sent to the laboratory of the university. Later, four larvae of Tenebrio molitor of last instar were inserted, and the sets were maintained at the temperature of 25°C for seven days. After this period, the presence of dead larvae was verified, and the confirmation of the mortality by EPNs was evaluated using of White’s trap. The positive samples for EPNs were obtained from the cities of Chapecó and Concordia, which corresponded to 2% of the total soil samples.

Utility of Higher Plant Densities for Corn Performance Testing

Crop Science ◽  
1983 ◽  
Vol 23 (5) ◽  
pp. 863-867 ◽  
Author(s):  
A. F. Troyer ◽  
R. W. Rosenbrook
Keyword(s):  
Performance Testing ◽  
Higher Plant ◽  
Plant Densities

scholarly journals Floristic, structural, and allometric equations to estimate arboreal volume and biomass in a cerradão site

2017 ◽  
Vol 38 (4) ◽  
pp. 1691
Author(s):  
Eder Pereira Miguel ◽  
Alba Valéria Rezende ◽  
Fabrício Assis Leal ◽  
Eraldo Aparecido Trondoli Matricardi ◽  
José Marcelo Imana Encinas ◽  
...  
Keyword(s):  
Tree Species ◽  
Vertical Structure ◽  
Diversity Index ◽  
Species Group ◽  
Systematic Sampling ◽  
Ecological Groups ◽  
Floristic Diversity ◽  
Importance Value ◽  
Horizontal Structure ◽  
Standing Trees

This objective of this study was to characterize the floristic, structural, and ecological groups and to estimate the arboreal volume and biomass of a cerradão site in Palmas, Tocantins, Brazil. A forest inventory was conducted on 10.15 ha of the study area. Plots of 400-m2 were used for systematic sampling. All standing trees (dead or alive) with a breast-height diameter (DHB) greater than 5 cm were identified and measured. Floristic diversity and horizontal structure were assessed using the Shannon and importance value indices, respectively. Forest vertical structure was classified into three stratata and the tree species were categorized into ecological groups. Ninety tree volumes were rigorously cubed and weighed. Fresh- and dry biomass were sampled and estimated. Mathematical models were applied and adjusted to estimate tree volume and biomass. It was observed that the species Myrcia splendens and Emmotum nitens and the families Fabaceae and Chrysobalanaceae were dominant in our study site. The pioneer (613 individuals ha-1) and climax (530 individuals ha-1) tree species group predominated. The floristic diversity index was estimated as 3.35 nats ind- 1. The vertical structure analysis indicated fewer individuals in the superior stratum (13%) compared to the medium (63%) and inferior (24%) stratum. The Schumacher and Hall model showed better results with regard to estimated forest production. Forest volume and biomass estimates were 126.71 m³ ha-1 and 61.67 Mg ha-1, respectively. The studied cerradão area had high floristic diversity and climax species predominated. Since this cerradão is in close proximity to the Amazon biome, its volume and biomass stocks were higher than those estimated for other cerradão and forest formations within the Cerrado biome.

scholarly journals ESTRUTURA HORIZONTAL DE UM TRECHO DE FLORESTA OMBRÓFILA DENSA DAS TERRAS BAIXAS NA RESERVA BIOLÓGICA DE SOORETAMA, LINHARES, ES

FLORESTA ◽  
2011 ◽  
Vol 41 (2) ◽  
Author(s):  
Alessandro de Paula ◽  
João Juares Soares
Keyword(s):  
Spatial Distribution ◽  
Distribution Pattern ◽  
Species Distribution ◽  
Ecological Groups ◽  
Horizontal Structure ◽  
Shannon’S Index ◽  
Dense Forest ◽  
Ombrophilous Forest ◽  
Dense Ombrophilous Forest ◽  
Biological Reserve

Este trabalho teve como objetivo analisar a estrutura fitossociológica horizontal de um trecho da vegetação arbórea de uma floresta de tabuleiro. Foi realizada uma amostragem fitossociológica em 100 parcelas contíguas de 10 x 10 m, sendo amostrados os indivíduos com PAP ≥ 15 cm. Construiu-se a distribuição diamétrica e estimou-se o padrão de distribuição espacial das espécies. Foram amostrados 1519 indivíduos, distribuídos entre 265 espécies, 138 gêneros e 44 famílias. O índice de Shannon (H’) estimado foi de 4,87 nats/ind. As espécies com os maiores VI foram Rinorea bahiensis (Moric.) Kuntze, Eriotheca macrophylla (K. Schum.) A. Robyns e Sterculia speciosa K. Schum. Em relação aos grupos ecológicos, as secundárias tardias obtiveram mais que o dobro do VC e VI das secundárias iniciais. A distribuição diamétrica apresentada pelas pioneiras foi truncada, sendo que a das secundárias iniciais foi ampla. A predominância de espécies tolerantes ao sombreamento nos estágios iniciais de crescimento reforça a ideia de que o estádio sucessional encontra-se avançado. Foram encontradas 10 espécies com padrão de distribuição espacial agregado e 29 aleatório.Palavras-chave:Fitossociologia; estrutura horizontal; Floresta Ombrófila Densa; floresta de tabuleiro; floresta atlântica. AbstractHorizontal structure of Ombrophilous dense forest of lowlands in Sooretama Biological Reserve, Linhares. This work aimed to analyze horizontal structure of arboreal vegetation from a “tableland” forest. A phytosociological sample was carried out on 100 contiguous plots of 10 X 10 meters. We sampled the individuals with PBH ≥ 15 cm, built up the diametric distribution and estimated spatial species distribution pattern. We sampled 1519 individuals, which were distributed into 265 species, 138 genera and 44 families. Shannon’s Index (H’) was estimated at 4.87 nats/ind. Species with the highest IV were Rinorea bahiensis (Moric.) Kuntze, Eriotheca macrophylla (K. Schum.) A. Robyns and Sterculia speciosa K. Schum. In relation to ecological groups, the late secondary species obtained CV and IV, twice as much as the early secondary ones. Pioneers presented truncated diametric distribution, as long as the early secondary had a broader one. Shadow tolerant species predominance reinforces that successional stadium is advanced. It had been found 10 species with aggregated spatial distribution and 29 random ones.Keywords:              Phytosociology; horizontal structure; Dense Ombrophilous Forest; tabuleiro forest; atlantic forest.

scholarly journals Perceptions of environmental change and use of traditional knowledge to plan riparian forest restoration with relocated communities in Alcântara, Eastern Amazon

2014 ◽  
Vol 10 (1) ◽  
pp. 11 ◽  
Author(s):  
Danielle Celentano ◽  
Guillaume Rousseau ◽  
Vera Engel ◽  
Cristiane Façanha ◽  
Elivaldo de Oliveira ◽  
...  
Keyword(s):  
Environmental Change ◽  
Traditional Knowledge ◽  
Forest Restoration ◽  
Riparian Forest

Effect of plant densities and different environments on productivity and profitability of Yardlong bean (Vigna unguiculata sub sp. sesquipedalis)

2018 ◽  
Author(s):  
M. Manjesh ◽  
Nagarajappa Adivappar ◽  
V. Srinivasa ◽  
G. K. Girijesh ◽  
Sharanabasappa .
Keyword(s):  
Plant Height ◽  
Vigna Unguiculata ◽  
Production Economics ◽  
Higher Plant ◽  
Pod Yield ◽  
Plant Densities ◽  
Yardlong Bean ◽  
Benefit Cost ◽  
Pod Length ◽  
Plot Design

The present investigation was carried out during Kharif 2016 at ZAHRS, Navile, Shivamogga. The experiment was laid out in split plot design with three replications. There were 24 treatment combinations comprised of three different environments (polyhouse, shadenet and open field) and eight spacing treatments (45 cm x 30 cm, 45 cm x 45 cm, 45 cm x 60 cm, 45 cm x 75 cm, 60 cm x 30 cm, 60 cm x 45 cm, 60 cm x 60 cm, 60 cm x 75 cm). The obtained results showed that all the characters were markedly affected by different environments and spacing. Among different environments significantly higher plant height (325.17cm), number of primary branches (12.46), number of pods per plant (21.66), pod length (70.67 cm), pod girth (3.73 cm), pod weight per plant (31.13 g), yield per plant (458.21 g) and higher pod yield per 1000 m2 (1605.99 kg) were recorded in polyhouse. Among spacing treatments significantly higher number of primary branches (12.91), pods per plant (22.30), pod length (71.73 cm), pod girth (3.94 cm), pod weight per plant (33.11g) and pod yield per plant (547.86 g) were recorded with wider spacing of 60 cm x 75 cm. Highest plant height (294.29 cm) and yield per 1000 m2 (1791.68 kg) were recorded with the closer spacing of 45 cm x 30 cm. The interaction of different environments and spacing were found to be statistically non-significant for all the traits. The evaluation of production economics revealed that growing of Yardlong bean in open condition with 45 cm x 30 cm spacing was most remunerative option with a highest benefit: cost of 3.14.

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