scholarly journals Spatial patterns of insect herbivory within a forest landscape: the role of soil type and forest stratum

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Xinliang Shao ◽  
Qin Zhang ◽  
Xitian Yang

Abstract Background Insect herbivory has profound impacts on ecosystem processes and services. Although many efforts have been made to recognize the main drivers of insect herbivory at different scales, the results are inconsistent. One likely reason is that studies have insufficiently captured the spatially heterogeneous factors such as soil type and forest stratum within the stand that may significantly affect insect herbivory. In particular, there is a lack of studies that address the detailed spatial patterns of insect herbivory which are influenced by these factors. Methods We measured the detailed spatial patterns of insect herbivory on cork oak (Quercus variabilis Bl.) in response to soil type (gravel soil and loam) and forest stratum (the upper, lower, and sapling stratum), and correlated these patterns with a set of influencing factors (litter coverage, coverage of shrubs and herbs, soil nutrients, soil moisture, and leaf traits) in a forest landscape. Results Generally, insect herbivory was spatially heterogeneous within stands. Herbivory was significantly lower in gravel soil areas than in loam soil areas and the highest herbivory occurred in the lower stratum. However, there were also 41 individual plots in which the highest herbivory occurred in the upper stratum and 29 plots in which the highest herbivory occurred in the sapling stratum. There were significant differences in soil nutrient and water status between soil types, but no significant differences in leaf traits. The effects of forest stratum on leaf traits were also inconsistent with those on insect herbivory. Conclusions Leaf traits may not be the main factors influencing insect herbivory in the field. Soil type may have major effects on herbivory patterns by influencing litter coverage while higher coverage of shrubs and herbs may reduce herbivory in the sapling stratum. These findings may advance our understanding of tree-herbivore interactions in real-world situations and have important implications for the sustainable management of forest ecosystems.

2008 ◽  
Vol 146 (6) ◽  
pp. 677-687 ◽  
Author(s):  
J. F. HERENCIA ◽  
J. C. RUIZ ◽  
S. MELERO ◽  
P. A. GARCIA GALAVÍS ◽  
C. MAQUEDA

SUMMARYThe transition from conventional to organic farming is accompanied by changes in soil chemical properties and processes that could affect soil fertility. The organic system is very complex and the present work carries out a short-term comparison of the effects of organic and conventional agriculture on the chemical properties of a silty loam soil (Xerofluvent) located in the Guadalquivir River Valley, Seville, Spain, through a succession of five crop cycles over a 3-year period. Crop rotation and varieties were compared in a conventional system using inorganic fertilizer and two organic systems using either plant compost or manure. At the end of the study, organic farming management resulted in higher soil organic carbon (OC), N and available P, K, Fe and Zn. The available Mn and especially Cu values did not show significant differences. In general, treatment with manure resulted in more rapid increases in soil nutrient values than did plant compost, which had an effect on several crop cycles later. The present study demonstrated that the use of organic composts results in an increase in OC and the storage of nutrients, which can provide long-term fertility benefits. Nevertheless, at least 2–3 years of organic management are necessary, depending on compost characteristics, to observe significant differences. Average crop yields were 23% lower in organic crops. Nevertheless, only two crops showed statistically significant differences.


2021 ◽  
Author(s):  
Mengjiao Sun ◽  
Enqing Hou ◽  
Jiasen Wu ◽  
Jianqin Huang ◽  
Xingzhao Huang

Abstract Background: Soil nutrients play critical roles in regulating and improving the sustainable development of economic forests. Consequently, an elucidation of the spatial patterns and drivers of soil nutrients in these forests is fundamental to their management. For this study, we collected 314 composite soils at a 0-30 cm depth from a typical hickory plantation in Lin 'an, Zhejiang Province, China. We determined the concentrations of macronutrients (i.e., soil organic carbon, hydrolyzed nitrogen, available phosphorus, and available potassium) and micronutrients (i.e., iron, manganese, zinc, and copper.) of the soils. We employed random forest analysis to quantify the relative importance of soil-forming factors to predict the soil nutrient concentrations, which could then be extrapolated to the entire hickory region. Results: Random forest models explained 61%–88% of the variations in soil nutrient concentrations. The mean annual temperature and mean annual precipitation were the most important predictor of soil macronutrient and micronutrient concentrations. Moreover, parent material was another key predictor of soil available phosphorus and micronutrient concentrations. Mapping results demonstrated the importance of climate in controlling the spatial distribution of soil nutrient concentrations at finer scales, as well as the effect of parent material, topography, stand structure, and management measures of hickory plantations. Conclusions: Our study highlights the biotic factors, abiotic factors, and management factors control over soil macronutrient and micronutrient concentrations, which have significant implications for the sustainability of soil nutrients in forest plantations.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Xiaolin Wang ◽  
Hongxuan Zhou ◽  
Fengsen Han ◽  
Yuanzheng Li ◽  
Dan Hu
Keyword(s):  

2014 ◽  
Vol 1 (2) ◽  
pp. 81
Author(s):  
Lutfi Izhar ◽  
Anas D. Susila

<p>ABSTRACT</p><p><br />Vegetables are important agricultural commodities. Productivity of vegetables in Indonesia is still low. One effort that can be done is an application of specific fertilizer recommendations. Fertilizer recommendation based on soil analysis is still rarely for vegetable crops and need further development. The purpose of this paper is to describe some fertilizer recommendations based on soil analysis for vegetable crops. Three stages to consider in the assessment of the research such as soil incubation, correlation test, calibration test and fertilizer <br />recommendation statue. Application all this stages of soil method recommendation in Indonesia is still not widely applied. Two researches which were completed until the entire stage has been done for yard long beans and <br />tomatoes. Recommendations for tomatoes on Inceptisols soil type with very low nutrient status of soil K was 180 kg K2O ha- 1, a low K soil nutrient status was 131.4 kg K2O ha-1, soil K nutrient status was 82.2 kg K 2O ha-1. Yard <br />long bean that planted on Ultisol soil type with low soil P nutrient status was recommended by an application of 185.8 kg P2O5 ha-1, medium soil P nutrient status was added 174.9 kg P2O5 ha-1. Development of fertilizer recommendation based on soil testing to support agricultural development in Indonesia still has some problems and need some strategies for further research, application and dissemination in the future.</p><p>Key words: vegetables, soil test, fertilizer recommendation</p>


Author(s):  
Progress Oghenerume ◽  
Samuel Eduok ◽  
Basil Ita ◽  
Ofonime John ◽  
Inemesit Bassey

We evaluated the effect of 4000 mg zinc oxide (ZnO, 99%, 30 nm) nanoparticle on the physicochemical and microbiological properties of organic manure amended ultisol and loam soil cultivated with Arachis hypogaea using standard methods. The results indicate varying effects on the physicochemical properties in relation to the soil type. The pH of the control ultisol at 7.85 ± 0.17 and 8.3 ± 0.12 in the amended ultisol whereas, the control loam was 7.15 ± 0.17 and 7.41 ± 0.11 in the amended soil indicating 1.06- and 1.04-times higher difference than the controls respectively.  Phosphorus concentration at 57.82 ± 0.54%, 50.81 ± 0.22% and 55.97 ± 0.04%, 59.97 ± 0.02% was 1.14 times lower in the ZnO amended ultisol and 1.07 times higher in amended loam soil compared to the respective controls. The organic matter content in the control and amended ultisol was 2.28 ± 0.32% and 0.91 ± 0.02%, 3.68 ± 0.36% and 0.36 ± 0.02% in the control and amended loam soil. The concentration of nitrate in the control ultisol was 0.05 ± 0.01% and 0.03 ± 0.01% in the amended soil. The nitrate in the control loam soil was 0.08 ± 0.01% relative to 0.02 ± 0.01% in the treated soil and these differences were significant at p = 0.05. The concentration of nutritive salts was reduced and in contrast iron, copper, exchangeable acids, exchange capacity, clay and silt increased in the amended soils. Further to this, heterotrophic ammonia and nitrate-oxidizing bacterial population were inhibited in the amended soils and denitrifying organisms were stimulated. The organisms were members of the genera Pseudomonas, Xanthobacter, Enterobacter, Bacillus, Lactobacillus, Citrobacter, Nitrosomonas, Agromyces and Rhizobium. ZnO nanoparticles altered the soil physicochemical properties which exacerbated the negative effect on microbial abundance and varied with the soil type.


2016 ◽  
Author(s):  
Matheus Henrique Nunes ◽  
Matthew P. Davey ◽  
David Anthony Coomes

Abstract. Understanding the causes of variation in plant functional traits is a central issue in ecology, particularly in the context of global change. Analyses of the drivers of traits variation based on thousands of tree species are starting to unravel patterns of variation at the global scale, but these studies tend to focus on interspecific variation, and the contribution of intraspecific changes remains less well understood. Hyperspectroscopy is a recently developed technology for estimating the traits of fresh leaves. Few studies have evaluated its potential for assessing inter- and intra-specific trait variability in community ecology. Working with 24 leaf traits for European tree species on contrasting soil types, found growing on deep alluvial soils and nearby shallow chalk soils, we ask: (i) What contribution do soil type and species identity make to trait variation? (ii) When traits are clustered into three functional groups (light capture and growth, leaf structure and defence, as well as rock-derived nutrients), are some groups more affected by soil than others? (iii) What traits can be estimated precisely using field spectroscopy? (iv) Can leaf spectra be used to detect inter-soil as well as inter-specific variation in traits? The contribution of species and soil-type effects to variation in traits were evaluated using statistical analyses. Foliar traits were predicted from spectral reflectance using partial least square regression, and so inter- and intra-specific variation. Most leaf traits varied greatly among species. The effects of soil type were generally weak by comparison. Macronutrient concentrations were greater on alluvial than chalk soils while micronutrient concentration showed the opposite trend. However, structural traits, as well as most pigments and phenolic concentrations varied little with soil type. Field spectroscopy provided accurate estimates of species-level trait values, but was less effective at detecting subtle variation of rock-derived nutrients between soil types. Field spectroscopy was a powerful technique for estimating cross-species variation in foliar traits and Si predictions using spectroscopy appear to be promising. However, it was unable to detect subtle within-species variation of traits associated with soil type.


Insects ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 865
Author(s):  
Zuzana Münzbergová ◽  
Jiří Skuhrovec

Data on plant herbivore damage as well as on herbivore performance have been previously used to identify key plant traits driving plant–herbivore interactions. The extent to which the two approaches lead to similar conclusions remains to be explored. We determined the effect of a free-living leaf-chewing generalist caterpillar, Spodoptera littoralis (Lepidoptera: Noctuidae), on leaf damage of 24 closely related plant species from the Carduoideae subfamily and the effect of these plant species on caterpillar growth. We used a wide range of physical defense leaf traits and leaf nutrient contents as the plant traits. Herbivore performance and leaf damage were affected by similar plant traits. Traits related to higher caterpillar mortality (higher leaf dissection, number, length and toughness of spines and lower trichome density) also led to higher leaf damage. This fits with the fact that each caterpillar was feeding on a single plant and, thus, had to consume more biomass of the less suitable plants to obtain the same amount of nutrients. The key plant traits driving plant–herbivore interactions identified based on data on herbivore performance largely corresponded to the traits identified as important based on data on leaf damage. This suggests that both types of data may be used to identify the key plant traits determining plant–herbivore interactions. It is, however, important to carefully distinguish whether the data on leaf damage were obtained in the field or in a controlled feeding experiment, as the patterns expected in the two environments may go in opposite directions.


Sign in / Sign up

Export Citation Format

Share Document