Western spruce budworm effects on throughfall N, P, and C fluxes and soil nutrient status in the Pacific Northwest

Western spruce budworm (Choristoneura freemani Razowski, 2008) is the most widely distributed insect herbivore in western North American coniferous forests. By partially or completely defoliating tree crowns, budworms influence fluxes of water, nutrients, and organic carbon from forest canopies to soils and, in turn, soil chemistry. To quantify these effects, throughfall water, inorganic nitrogen (N), phosphorus (P), and dissolved organic carbon (DOC) concentrations, as well as fluxes and soil N and P concentrations, were measured in coniferous forest sites with high and background levels of budworm herbivory. Throughfall N and P concentrations and fluxes increased at sites with high budworm levels during and (or) immediately after larval-stage budworm feeding, indicating reduced uptake and (or) greater leaching from canopies as a result of budworm activity. Annual throughfall N fluxes (<67–71 g N·ha−1·year−1) and soil N concentrations were low regardless of herbivory level. In contrast, throughfall P was considerably greater at sites with high herbivory levels (2174 g P·ha−1·year−1) compared with those with background levels (1357 g P·ha−1·year−1), and this was reflected in nearly threefold higher soil P concentrations at sites with high budworm levels. Our findings suggest that by altering throughfall chemistry and soil N:P, budworms could influence elemental export from watersheds.

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Conservation Practice, Irrigation and Fertilizer Dose Influence Yield and Quality of Mango cv. Amrapali under High Density Orchard in Kosi Zone of Bihar

Current Journal of Applied Science and Technology ◽

10.9734/cjast/2019/v37i630337 ◽

2019 ◽

pp. 1-6

Author(s):

Radhey Shyam ◽

Suraj Prakash ◽

Janardan Prasad

Keyword(s):

Organic Carbon ◽

Microbial Population ◽

Fruit Yield ◽

Conservation Practices ◽

Soil N ◽

Conservation Practice ◽

Soil P ◽

Soil Microbial ◽

Conservation Treatment ◽

Soil Microbial Population

An investigation was carried out during three consecutive years from 2016-17 to 2018-19 at farm of B.P.S. Agricultural college, Purnea on Mango cv. Amrapali to study the effect of conservation practice of mulch with irrigation and fertilizer levels on yield and soil parameter, fruit yield and its qualities of mango grown in kosi zone of Bihar. The experiment was laid out in split split plot design with three replications. Experimental findings revealed that conservation practices as mulch significantly increased fruit set, fruit retention, fruit yield and fruit quality. Among different irrigation levels and fertilizer doses maximum fruit yield (23.24 ton/ha) was obtained under conservation practice with 75% recommended irrigation along with 100% RDF which was at par with conservation practice with 75% recommended irrigation along with 75% RDF. Conservation treatment also showed maximum TSS (23.69° Brix) with maximum (0.39%) acidity of fruit. Observations also revealed that conservation practices as mulching significantly increased the soil moisture content, organic carbon %, available soil N, P and K, along with increase soil microbial population. Among the different fertilizer levels highest organic carbon %, available soil N, P and K, as well as soil microbial population were observed with 100% RDF, however only organic carbon and available soil P were at par with 75% RDF.

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Environmental plantings’ influence on microbial attributes and soil properties in Australia.

10.5194/egusphere-egu21-1014 ◽

2021 ◽

Author(s):

Apsara Amarasinghe ◽

Oliver G G Knox ◽

Christine Fyfe ◽

Lisa A Lobry de Bruyn ◽

Brian R Wilson

Keyword(s):

Organic Carbon ◽

Microbial Activity ◽

Functional Diversity ◽

Nutrient Status ◽

Tree Age ◽

Ecosystem Functions ◽

Ecosystem Recovery ◽

Microbial Functional Diversity ◽

Soil P ◽

Remnant Vegetation

<p>Native trees and shrubs planted in large contiguous blocks (environmental plantings) have been established on agricultural lands in Australia to reinstate ecosystem functions and protect the biodiversity that has been degraded by agricultural activities. Limited work exists on the extent of the ecosystem recovery, but the assessment of microbial attributes (i.e. microbial activity and functional diversity) in these plantings may provide an indication of status. This study investigated how environmental plantings, and time since their establishment, affects aforementioned soil microbial attributes, &#160;to determine if the recovery to conditions found under extant remnant woodland were achievable. We compared changes in microbial functional diversity and activity along with total organic carbon (TOC), total nitrogen (TN), extractable phosphorous (P), soil pH, and electrical conductivity (EC) between environmental plantings established for 17 and 27 years, a paired adjacent pasture, and nearby remnant native woodland at Gunnedah, New South Wales. The results indicated that microbial activity under the trees, compared to that of pasture, increased by 20%&#8211;93% with increasing tree age. The ordination distance of microbial functional diversity declined between environmental plantings and remnant woodland as the age of the environmental planting increased, which was indicative of microbial functions becoming similar to that in the remnant vegetation with time. Soil P levels under trees were significantly higher compared to pasture and also increased with increasing planting age. However, TOC and TN levels under environmental plantings remained similar to pasture. These results suggest that microbial attributes and soil nutrient status of the investigated environmental plantings were on a trajectory of change from that of the pasture systems toward that of the remnant vegetation, but that full ecosystem recovery had not yet been achieved, even after 27 years.</p><p>Keywords: Environmental plantings, Microbial activity, Microbial functional diversity, Soil organic carbon, Soil nutrients</p>

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Spatiotemporal dynamics of recent mountain pine beetle and western spruce budworm outbreaks across the Pacific Northwest Region, USA

Forest Ecology and Management ◽

10.1016/j.foreco.2014.11.030 ◽

2015 ◽

Vol 339 ◽

pp. 71-86 ◽

Cited By ~ 46

Author(s):

Garrett W. Meigs ◽

Robert E. Kennedy ◽

Andrew N. Gray ◽

Matthew J. Gregory

Keyword(s):

Pacific Northwest ◽

Mountain Pine Beetle ◽

Spruce Budworm ◽

Spatiotemporal Dynamics ◽

Western Spruce Budworm ◽

Mountain Pine ◽

The Pacific ◽

Pine Beetle ◽

Northwest Region

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Trends of Western Spruce Budworm and Associated Insects in Pacific Northwest Forests Sprayed with DDT12

Journal of Economic Entomology ◽

10.1093/jee/64.1.291 ◽

1971 ◽

Vol 64 (1) ◽

pp. 291-297 ◽

Cited By ~ 3

Author(s):

V. M. Carolin ◽

W. K. Coulter

Keyword(s):

Pacific Northwest ◽

Spruce Budworm ◽

Western Spruce Budworm

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Drought-triggered western spruce budworm outbreaks in the interior Pacific Northwest: A multi-century dendrochronological record

Forest Ecology and Management ◽

10.1016/j.foreco.2014.03.042 ◽

2014 ◽

Vol 324 ◽

pp. 16-27 ◽

Cited By ~ 42

Author(s):

A. Flower ◽

D.G. Gavin ◽

E.K. Heyerdahl ◽

R.A. Parsons ◽

G.M. Cohn

Keyword(s):

Pacific Northwest ◽

Spruce Budworm ◽

Western Spruce Budworm

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A method for sampling western spruce budworm pupae.

10.2737/pnw-rn-372 ◽

1981 ◽

Author(s):

Nilima Srivastava ◽

Roy C. Beckwith ◽

Robert W. Campbell ◽

Torolf R. Torgersen

Keyword(s):

Spruce Budworm ◽

Western Spruce Budworm

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Peroral bioassay of nucleopolyhedrosis viruses in larvae of western spruce budworm.

10.2737/pnw-rp-285 ◽

1981 ◽

Cited By ~ 1

Author(s):

Mauro E. Martignoni ◽

Paul J. Iwai

Keyword(s):

Spruce Budworm ◽

Western Spruce Budworm

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Effects of Urban Forest Types and Traits on Soil Organic Carbon Stock in Beijing

Forests ◽

10.3390/f12040394 ◽

2021 ◽

Vol 12 (4) ◽

pp. 394

Author(s):

Xinhui Xu ◽

Zhenkai Sun ◽

Zezhou Hao ◽

Qi Bian ◽

Kaiyue Wei ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Stock ◽

Urban Forest ◽

Coniferous Forest ◽

Predictor Variable ◽

Urban Forests ◽

Least Squares Regression ◽

Forest Types ◽

Organic Carbon Stock

Forests can affect soil organic carbon (SOC) quality and distribution through forest types and traits. However, much less is known about the influence of urban forests on SOC, especially in the effects of different forest types, such as coniferous and broadleaved forests. Our objectives were to assess the effects of urban forest types on the variability of SOC content (SOC concentration (SOCC) and SOC density (SOCD)) and determine the key forest traits influencing SOC. Data from 168 urban forest plots of coniferous or broadleaved forests located in the Beijing urban area were used to predict the effects of forest types and traits on SOC in three different soil layers, 0–10 cm, 10–20 cm, and 20–30 cm. The analysis of variance and multiple comparisons were used to test the differences in SOC between forest types or layers. Partial least squares regression (PLSR) was used to explain the influence of forest traits on SOC and select the significant predictors. Our results showed that in urban forests, the SOCC and SOCD values of the coniferous forest group were both significantly higher than those of the broadleaved group. The SOCC of the surface soil was significantly higher than those of the following two deep layers. In PLSR models, 42.07% of the SOCC variance and 35.83% of the SOCD variance were explained by forest traits. Diameter at breast height was selected as the best predictor variable by comparing variable importance in projection (VIP) scores in the models. The results suggest that forest types and traits could be used as an optional approach to assess the organic carbon stock in urban forest soils. This study found substantial effects of urban forest types and traits on soil organic carbon sequestration, which provides important data support for urban forest planning and management.

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Soil organic carbon storage by shaded and unshaded coffee systems and its implications for climate change mitigation in China

The Journal of Agricultural Science ◽

10.1017/s002185962100006x ◽

2021 ◽

pp. 1-8

Author(s):

Ziwei Xiao ◽

Xuehui Bai ◽

Mingzhu Zhao ◽

Kai Luo ◽

Hua Zhou ◽

...

Keyword(s):

Climate Change ◽

Linear Regression ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Multiple Linear Regression ◽

Carbon Storage ◽

Soil Ph ◽

Soil Bulk Density ◽

Soil N ◽

And Storage

Abstract Shaded coffee systems can mitigate climate change by fixation of atmospheric carbon dioxide (CO2) in soil. Understanding soil organic carbon (SOC) storage and the factors influencing SOC in coffee plantations are necessary for the development of sound land management practices to prevent land degradation and minimize SOC losses. This study was conducted in the main coffee-growing regions of Yunnan; SOC concentrations and storage of shaded and unshaded coffee systems were assessed in the top 40 cm of soil. Relationships between SOC concentration and factors affecting SOC were analysed using multiple linear regression based on the forward and backward stepwise regression method. Factors analysed were soil bulk density (ρb), soil pH, total nitrogen of soil (N), mean annual temperature (MAT), mean annual moisture (MAM), mean annual precipitation (MAP) and elevations (E). Akaike's information criterion (AIC), coefficient of determination (R2), root mean square error (RMSE) and residual sum of squares (RSS) were used to describe the accuracy of multiple linear regression models. Results showed that mean SOC concentration and storage decreased significantly with depth under unshaded coffee systems. Mean SOC concentration and storage were higher in shaded than unshaded coffee systems at 20–40 cm depth. The correlations between SOC concentration and ρb, pH and N were significant. Evidence from the multiple linear regression model showed that soil bulk density (ρb), soil pH, total nitrogen of soil (N) and climatic variables had the greatest impact on soil carbon storage in the coffee system.

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