Identification of the environmental factors which drive the botanical and functional composition of permanent grasslands

2011 ◽  
Vol 150 (2) ◽  
pp. 219-236 ◽  
Author(s):  
A. MICHAUD ◽  
S. PLANTUREUX ◽  
B. AMIAUD ◽  
P. CARRÈRE ◽  
P. CRUZ ◽  
...  
Keyword(s):  
Climatic Factors ◽  
Present Report ◽  
Floristic Composition ◽  
Matter Content ◽  
Species Number ◽  
Dry Matter Content ◽  
Functional Composition ◽  
Botanical Composition ◽  
Functional Characteristics ◽  
Species Dominance

SUMMARYManaged grasslands provide environmental and agronomic services that can be predicted from the botanical and functional composition of the vegetation. These are influenced by management, edaphic and climatic factors. The present report set out to estimate and analyse the relative importance of management, soil and climate factors on botanical and functional characteristics of grassland vegetation. A set of 178 French grasslands having a large pedoclimatic and management gradient was selected, and information collected on botanical composition, pedoclimatic factors and management. Six vegetation characteristics were considered: two botanical (floristic composition and species dominance) and four functional (proportion of entomophilous species, number of oligotrophic species, leaf dry matter content and date of flowering). First, the links between the characteristics of the vegetation were analysed to check for any redundancy among them; all were kept. Second, it was demonstrated that botanical and functional characteristics were not driven by the same factors: functional composition was characterized by management, edaphic and climatic factors, whereas botanical composition was influenced mainly by climatic and edaphic factors plus other factors. Interactions between factors also have to be taken into consideration to predict botanical and functional composition of grasslands. Functional and botanical characteristics of vegetation help to predict ecosystem services delivered by grasslands and may be used in combination.

Sample size and sampling intensity in relation to the precision of small-plot herbage sward trials

1968 ◽  
Vol 70 (1) ◽  
pp. 19-27 ◽  
Author(s):  
C. A. Foster ◽  
C. E. Wright
Keyword(s):  
Sample Size ◽  
Dry Matter ◽  
Matter Content ◽  
Dry Matter Content ◽  
Dry Matter Yield ◽  
Botanical Composition ◽  
Plot Size ◽  
Sampling Intensity ◽  
Length Measurements ◽  
Small Plot

SummeryThree sampling experiments were conducted to examine the effect of sample size and sampling intensity on the precision of dry-matter content and botanical composition estimates of perennial rye-grass-white clover herbage. One of these experiments examined the between-sample variability of these attributes and of dry-matter yield in relation to other sources of experimental error in a small-plot sward trial. The sample sizes examined were 800 g, 400 g, 200 g, 100 g, 50 g and 25 g green weight. In general the accuracy of dry-matter content and botanical composition estimates decreased with decreasing sample size. The between-sample variabilities of 25 g and 50g samples were high in relation to their between-plot variabilities. Single 100 g samples provided reasonably good estimates of these attributes and of dry-matter yield, but single 200 g samples provided a more satisfactory margin for error. Samples larger than 200 g appeared to be unnecessary. When weight-for-weight comparisons of single and duplicate samples were made there appeared to be little advantage in duplicate sampling. A theoretical examination of measurement inaccuracies inherent in the techniques used in small-plot sward trialssuggested that variation in plot length measurements in particular may make an undesirable contribution to the variability of such trials. A procedure for the conduct of small-plot trials is recommended. It is concluded that, where plot size and replication are limited, further improvement in the precision of such trials will not be readily attainable.

scholarly journals Above- and Belowground Plant Functional Composition Show Similar Changes During Temperate Forest Swamp Succession

2021 ◽  
Vol 12 ◽  
Author(s):  
Yu-Kun Hu ◽  
Xu Pan ◽  
Xu-Yan Liu ◽  
Zhi-Xi Fu ◽  
Man-Yin Zhang
Keyword(s):  
Functional Diversity ◽  
Soil Ph ◽  
Community Assembly ◽  
Temperate Forest ◽  
Dry Matter ◽  
Fine Root ◽  
Root Traits ◽  
Matter Content ◽  
Dry Matter Content ◽  
Functional Composition

Plant functional composition, defined by both community-weighted mean (CWM) traits and functional diversity, can provide insights into plant ecological strategies and community assembly. However, our understanding of plant functional composition during succession is largely based on aboveground traits. Here we investigated community-level traits and functional diversity for six pairs of analogous leaf and fine root traits of understory plants in a temperate forest swamp during succession with a decrease in soil pH and nutrient availability. CWMs of traits related to resource acquisition (including specific leaf area, specific root length, leaf N, leaf P, root N, and root P) decreased with succession, whereas those related to resource conservation (leaf dry matter content, root dry matter content, leaf tissue density, leaf C, and root C) increased along the forest swamp successional gradient. Multi-trait functional dispersion (FDis) of both leaf and fine root traits tended to decrease along the successional gradient, but functional richness and evenness were highest at the middle successional stage. Moreover, FDis of individual plant traits except N showed the same pattern as multi-trait FDis. Soil pH and nutrient availability were the main drivers of successional changes in both CWM traits and FDis. The changes of community-level traits along succession indicated a shift from acquisitive to conservative strategy of understory plants during forest swamp succession. Similar trends in leaf and fine root functional diversity along succession may indicate above- and belowground functional diversity are coordinated during the processes of plant community assembly. These findings of linkages between above- and belowground plant functional composition have important implications for plant community dynamics and assembly rules.

scholarly journals Potato Maximum Yield as Affected by Crop Parameters and Climatic Factors in Brazil

HortScience ◽  
2008 ◽  
Vol 43 (5) ◽  
pp. 1611-1614 ◽  
Author(s):  
André Pereira ◽  
Nilson Villa Nova
Keyword(s):  
Dry Matter ◽  
Climatic Factors ◽  
Maximum Yield ◽  
Crop Productivity ◽  
Matter Content ◽  
Dry Matter Content ◽  
Potato Tubers ◽  
Tropical Conditions ◽  
Potato Yields ◽  
Crop Parameters

There is currently a great deal of interest in estimating crop productivity as a function of climatic factors by means of different crop weather models. In this article, an agrometeorological model based on maximum carbon dioxide assimilation rates for C3 plants, fraction of photosynthetically active radiation, air temperature, photoperiod duration, and crop parameters is assessed as to its performance under tropical conditions. Crop parameters include leaf area, harvest index, dry matter content of potato tubers, and crop cycles to estimate potential potato yields. Productivity obtained with the cultivar Itararé, grown with adequate soil water supply conditions at four different sites in the state of São Paulo (Itararé, Piracicaba, Tatuí, and São Manuel), Brazil, was used to test the model. The results revealed excellent performance of the agrometeorological model proposed here with an underestimation of irrigated potato productivity of less than 10%.

scholarly journals Effect of Climatic Conditions on Differences in Thermo-Technical Properties of Organic Bedding in Laboratory Testing

2017 ◽  
Vol 20 (1) ◽  
pp. 1-6
Author(s):  
Jana Lendelová ◽  
Ingrid Karandušovská ◽  
Miroslav Žitňák ◽  
Štefan Boďo ◽  
Štefan Mihina
Keyword(s):  
Thermal Conductivity ◽  
Thermal Resistance ◽  
Thermal Performance ◽  
Dry Matter ◽  
Climatic Factors ◽  
Climatic Conditions ◽  
Matter Content ◽  
Dry Matter Content ◽  
Liquid Manure ◽  
Technical Properties

Abstract The aim of this experiment was to analyse the influence of climatic factors on the thermal performance of separated liquid manure. The samples of organic bedding were collected from the lying area of dairy housing and preparatory store. The measurement of properties of recycled manure solids (RMS) was carried out in laboratory conditions. Samples were examined with determining the temperature effect on the thermal conductivity λ of ’dry‘ separated liquid manure (with a dry matter content of 60%) and ’wet‘ liquid manure (with a dry matter content of 26%), in air temperatures ranging from 0 °C to 40 °C. Subsequently, the thermal resistance of three selected types of cows lying structures was calculated for winter and summer boundary values. Based on the results of thermal conductivity and thermal resistance, it was observed that dry separated liquid manure as an alternative bedding has, in low temperature (up to 5 °C), the most suitable thermal performance if it is maintained in a dry condition (with a dry matter content of 60%). With increasing temperature (above 20 °C) and increasing humidity of bedding (below 26%), thermo-technical properties get worse; however, when comparing the thermal resistance of the cow bed structure with sandwich mattresses with a 50 mm layer of organic bedding and the deep cubicle filled with 200 mm of organic bedding, the thermal resistance of floor structure decreases by 7.6% or 18.4%, respectively. With a proper handling of the recycled organic bedding, it is possible to use its economic advantages.

Climatic Factors and Potato Growth

1966 ◽  
Vol 2 (2) ◽  
pp. 129-137 ◽  
Author(s):  
E. G. B. Gooding
Keyword(s):  
Dry Matter ◽  
Climatic Factors ◽  
Inverse Correlation ◽  
Matter Content ◽  
High Yield ◽  
Dominant Factor ◽  
Dry Matter Content ◽  
High Rainfall ◽  
High Dry Matter ◽  
Potato Growth

SummaryIn connection with the processing of potatoes grown at Tarland, Aberdeenshire, certain field data were obtained over a period of eight years. It was found that the yield per acre was inversely correlated with rainfall and positively correlated with sunshine for the period May to September; the indications were that the period May to July was more important in this respect, high rainfall and low sunshine during this period depressing the crop more than high rainfall in the August to September period. It has been possible, statistically, to separate the effect of rainfall from that of sunshine (and temperature), and an analysis shows that sunshine (or temperature) is die dominant factor. The number of tubers produced was greatest in those years when sunshine was high and rainfall low. The dry matter content of die tubers was also highest when the sunshine was high and the rainfall low, the closest inverse correlation being with the rainfall for the month of August. The combination of high yield of potatoes and high dry matter content meant that the actual food produced was highest in the drier, more sunny, years.

Evaluation of techniques for estimating the yield of irrigated pastures intensively grazed by dairy cows. 2. The rising plate meter

1984 ◽  
Vol 24 (126) ◽  
pp. 305 ◽  
Author(s):  
CR Stockdale
Keyword(s):  
Dairy Cows ◽  
Dry Matter ◽  
Visual Assessment ◽  
Matter Content ◽  
Dry Matter Content ◽  
Botanical Composition ◽  
Assessment Technique ◽  
Grazed Pastures ◽  
Number Of Factors ◽  
Short Period

A semi-automatic rising plate meter, the Ellinbank Pasture Meter (EPM) was used to estimate herbage yields of the three most common types of irrigated pasture intensively grazed by dairy cows in northern Victoria. While there were only small differences in precision between the pasture types, yields of pre-grazed pastures were measured more precisely than yields of post-grazed pastures. The EPM also estimated pre-grazing yield more precisely than a visual assessment technique, while the two techniques were similar for estimating post-grazed herbage. A number of factors, including dry matter content of the herbage, botanical composition, season, and lodging due to trampling were shown to influence pre- and post-grazing regressions. It was concluded that pooled regressions were therefore unsuitable for research purposes unless the pooling was for a relatively short period only. Pre- and post-grazing data can be pooled for periods of up to two months to allow the estimation of pasture growth rates at various points of time between grazings. An alternative method of obtaining yield estimates has been proposed in which it is not necessary to develop a regression. This method relies on cutting quadrats in each plot that are representative of the yield and composition of the plot. While this method can circumvent some of the problems associated with the factors that influence the yield-height relationship, severe lodging due to trampling of the sward may preclude the use of the EPM regardless of method.

Optimum harvest date of maize for biogas and silage purposes

2009 ◽  
Vol 57 (2) ◽  
pp. 119-125
Author(s):  
G. Hadi
Keyword(s):  
Dry Matter ◽  
Biogas Production ◽  
Weather Conditions ◽  
Vegetation Period ◽  
Dry Mass ◽  
Matter Content ◽  
Harvest Date ◽  
Dry Matter Content ◽  
Dry Matter Yield ◽  
Vegetative Organs

The dry matter and moisture contents of the aboveground vegetative organs and kernels of four maize hybrids were studied in Martonvásár at five harvest dates, with four replications per hybrid. The dry matter yield per hectare of the kernels and other plant organs were investigated in order to obtain data on the optimum date of harvest for the purposes of biogas and silage production.It was found that the dry mass of the aboveground vegetative organs, both individually and in total, did not increase after silking. During the last third of the ripening period, however, a significant reduction in the dry matter content was sometimes observed as a function of the length of the vegetation period. The data suggest that, with the exception of extreme weather conditions or an extremely long vegetation period, the maximum dry matter yield could be expected to range from 22–42%, depending on the vegetation period of the variety. The harvest date should be chosen to give a kernel moisture content of above 35% for biogas production and below 35% for silage production. In this phenophase most varieties mature when the stalks are still green, so it is unlikely that transport costs can be reduced by waiting for the vegetative mass to dry.

Persistence of modern varieties and hybrids of carrots and its dependence on the biochemical composition

2020 ◽  
pp. 16-19
Author(s):  
Е.В. Янченко
Keyword(s):  
Botrytis Cinerea ◽  
Sclerotinia Sclerotiorum ◽  
Dry Matter ◽  
Inverse Correlation ◽  
Dry Weight ◽  
Matter Content ◽  
White Rot ◽  
Dry Matter Content ◽  
Important Indicator ◽  
Modern Varieties

Цель исследований – дать оценку сохраняемости и болезнеустойчивости современных сортов и гибридов моркови столовой и определить корреляционные зависимости влияния биохимических показателей качества на сохраняемость и степень поражения моркови столовой различными видами болезней в процессе хранения. Исследования проводились в 2011–2016 годах во ВНИИО – филиале ФГБНУ ФНЦО по общепринятым методикам. В биохимической лаборатории отдела земледелия и агрохимии содержание сухого вещества определяли высушиванием до абсолютно сухого веса, общего сахара – по Бертрану, аскорбиновой кислоты – по Мурри, нитраты – ионоселективным методом. При характеристике моркови столовой важнейший показатель, определяющий его качество – количество сухого вещества и сахаров. В процессе хранения были выявлены следующие болезни моркови: серая гниль (Botrytis cinerea Pers. ex Fr.), белая гниль (Sclerotinia sclerotiorum (Lib.)), белая парша (Rhizoctonia carotae Rad.), альтернариоз (Alternaria radicina M., Dr. et E.). В большей степени сортообразцы моркови столовой поражались серой гнилью. Лучшими по сохраняемости сортообразцами были Корсар (94,6%), F1Берлин (94,5%), Берликум Роял (94,1%) и F1 Звезда (94%). Сохраняемость у зарубежных сортов и гибридов моркови столовой была немного выше, чем у отечественных (на 0,4%) как за счет меньшей величины убыли массы (6,3% против 6,4%), так и потерь от болезней (1,6% против 1,9%). Сохраняемость корнеплодов моркови находится в прямой корреляционной зависимости от содержания сухого вещества (r=+0,41), каротиноидов (r=+0,39), моносахаров (r­=+0,30) и суммы сахаров (r=+0,27). Проявление серой гнили находится в обратной корреляционной связи с содержанием сухого вещества и каротиноидов (r=-0,37 и r=-0,35 соответственно), белой парши – в прямой корреляции с содержанием сухого вещества , моносахаров и дисахаров (r= +0,21; r= +0,39; r= -0,41 соответственно), белой гнили в обратной корреляционной связи с содержанием сухого вещества, моносахаров и дисахаров. The purpose of the research is to assess the persistence and disease resistance of modern varieties and hybrids of carrots and to determine the correlation between the influence of biochemical quality indicators on the persistence and degree of damage to carrots by various types of diseases during storage. The research was conducted in 2011–2016 at ARRIVG – branch of FSBSI FSVC, according to generally accepted methods. In the biochemical laboratory of the Department of Agriculture and Agrochemistry, the dry matter content was determined by drying to absolutely dry weight, total sugar – by Bertran, ascorbic acid – by Murri, nitrates – by the ion-selective method. When describing carrots, the most important indicator that determines its quality is the amount of dry matter and sugars. During storage, the following diseases of carrots were detected: gray rot (Botrytis cinerea Pers. ex Fr.), white rot (Sclerotinia sclerotiorum (Lib.), white scab (Rhizoctonia carotae Rad.), alternariasis (Alternaria radicina M., Dr. et E.). To a greater extent, varieties of table carrots were affected by gray rot. The best preserved varieties were Corsar (94.6%), F1 Berlin (94.5%), Berlicum Royal (94.1%) and F1 Zvezda (94%). The persistence of foreign varieties and hybrids of table carrots was slightly higher than that of domestic ones by 0.4%. both due to a smaller amount of weight loss (6.3% vs. 6.4%) and losses from diseases (1.6% vs. 1.9%). The persistence of carrot root crops is directly correlated with the content of dry matter (r=+0.41), carotenoids (r=+0.39), monosaccharides (r=+0.30) and the amount of sugars (r=+0.27). The manifestation of gray rot is in inverse correlation with the content of dry matter and carotenoids (r=-0.37 and r=-0.35, respectively), white scab is in direct correlation with the content of dry matter (r= +0.21; r= +0.39; r= –0.41, respectively), white rot is in inverse correlation with the content of dry matter, monosaccharides and disaccharides.

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