Budget of Plant Litter and Litter Carbon in the Subalpine Forest Streams

Investigations on the budget of plant litter and litter carbon in forest streams can provide a key scientific basis for understanding the biogeochemical linkages of terrestrial–aquatic ecosystems and managing forest catchments. To understand the biogeochemical linkages among mountain forests, riparian vegetation, and aquatic ecosystems, the changes in litter input and output from the subalpine streams with stream characteristics and critical periods were investigated in an ecologically important subalpine coniferous forest catchment in the upper reaches of the Yangtze River. The annual litter input to the stream was 20.14 g m−2 and ranged from 2.47 to 103.13 g m−2 for 15 streams during the one-year investigation. Simultaneously, the litter carbon input to the stream was 8.61 mg m−2 and ranged from 0.11 to 40.57 mg m−2. Meanwhile, the annual litter output varied from 0.02 to 22.30 g m−2, and the average value was 0.56 g m−2. Correspondingly, the litter carbon output varied from 0.01 to 1.51 mg m−2, and the average value was 0.16 mg m−2. Furthermore, the average ratio of litter carbon input to output was 270.01. The maximum and minimum values were observed in the late growing season and the snowmelt season, respectively. Additionally, seasonal variations in temperature, together with the stream length, dominated the input of litter and litter carbon to the stream, while the precipitation, temperature, water level, and sediment depth largely determined their output. Briefly, the seasonal dynamics of litter and litter carbon were dominated by stream characteristics and precipitation as well as temperature patterns.

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Long-term effects of fire on the composition and activity of the soil microflora of a subalpine, coniferous forest

Canadian Journal of Botany ◽

10.1139/b80-199 ◽

1980 ◽

Vol 58 (15) ◽

pp. 1704-1721 ◽

Cited By ~ 60

Author(s):

J. Bissett ◽

D. Parkinson

Keyword(s):

Microbial Biomass ◽

Bacterial Flora ◽

Mineral Soil ◽

Coniferous Forest ◽

Soil Microflora ◽

Subalpine Forest ◽

Long Term Effects ◽

Soil Horizons ◽

Cellulose Decomposition ◽

Soil Temperatures

The biomass, community composition, and metabolic activity of soil microorganisms were studied in adjacent burnt and unburnt areas of spruce–fir subalpine forest razed 6 years previously by a moderately severe natural fire. Similar levels of microbial biomass were observed at comparable burnt and unburnt sites, although the ratio of fungal to bacterial biomass was higher in the unburnt soils. The decreased acidity of the surface horizons in the burn probably tended to favor the development of a bacterial flora rather than a fungal flora. Microbial biomass in the burnt sites peaked earlier in the season than in the unburnt sites in response to the warmer soil temperatures and earlier thaw in the spring in the burn area.Significant differences in the species composition of the mycoflora in the organic soil horizons were observed between the burnt and unburnt sites. Apparently, these were related to qualitative differences in the recent litter. Phoma, Cladosporium, and Botrytis, which are usually associated with early stages of decomposition of herbaceous litter, were more common in the burnt soil. The mycoflora of the mineral soil horizons varied considerably from one burn site to another, possibly reflecting the geographical variation in the intensity of the burn. In overall composition, however, the mycoflora in the mineral soil horizons of the burn was not appreciably different from that of the unburnt sites.Higher laboratory rates of respiration and cellulose decomposition were observed for soil samples from the undisturbed forest. However, the rate of decomposition of cellulose in the field was much higher in the burnt sites, probably as a result of the higher soil temperatures in the burn area. Low soil temperature was concluded to be the main factor limiting microbial activities in the study area, and the removal of the insulating plant canopy and increased heat absorption by the ash in the burn area were found to increase decomposition rates, at least at this stage in the succession following the disturbance of fire.

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Soil net methane uptake rates in response to short-term litter input change in a coniferous forest ecosystem of central China

Agricultural and Forest Meteorology ◽

10.1016/j.agrformet.2019.03.017 ◽

2019 ◽

Vol 271 ◽

pp. 307-315 ◽

Cited By ~ 1

Author(s):

Junjun Wu ◽

Meng Lu ◽

Jiao Feng ◽

Dandan Zhang ◽

Qiong Chen ◽

...

Keyword(s):

Forest Ecosystem ◽

Coniferous Forest ◽

Central China ◽

Short Term ◽

Litter Input ◽

Uptake Rates ◽

Methane Uptake

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Conidium production from leaves and needles in four streams

Canadian Journal of Botany ◽

10.1139/b82-190 ◽

1982 ◽

Vol 60 (8) ◽

pp. 1487-1494 ◽

Cited By ~ 59

Author(s):

Felix Bärlocher

Keyword(s):

Coniferous Forest ◽

Hard Water ◽

Experimental Period ◽

Unit Weight ◽

Coarse Mesh ◽

Black Forest ◽

Additional Species ◽

Conidium Production ◽

Fine Mesh ◽

Forest Streams

Oak leaves and larch and spruce needles in fine-mesh (0.3 mm) and coarse-mesh (3 mm) bags were exposed in two hard-water streams in the Swiss Jura and two soft-water streams in the Black Forest. Periodically, conidium production in samples was determined under defined conditions. Generally, conidium production per unit weight was highest in oak, followed by larch and spruce. In oak and larch, an early peak was followed by a gradual decline; in spruce, conidium production reached an early plateau in the Jura streams but increased throughout the experimental period in the Black Forest streams. Percentage similarity between substrate spora and stream spora was highest for oak, followed by larch and spruce in three of the streams with deciduous riparian vegetation. The reverse sequence occurred in the remaining stream of a coniferous forest. On oak and larch, more fungal species were recovered in fine-mesh than in coarse-mesh bags; however, these additional species were numerically unimportant. Heliscus lugdunensis was the dominant species in early stages of spruce decay. It was replaced at later stages by Alatospora acuminata in the Jura streams and by two other species in the Black Forest streams. On oak and larch, the four or five most common species remained dominant throughout the experimental period.

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Growth and emergence of the stonefly Leuctra nigra in coniferous forest streams with contrasting pH

Freshwater Biology ◽

10.1046/j.1365-2427.2002.00827.x ◽

2002 ◽

Vol 47 (6) ◽

pp. 1159-1172 ◽

Cited By ~ 18

Author(s):

ANNE G. THOMSEN ◽

NIKOLAI FRIBERG

Keyword(s):

Coniferous Forest ◽

Forest Streams

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Woody Litter Increases Headwater Stream Metal Export Ratio in an Alpine Forest

Forests ◽

10.3390/f10050379 ◽

2019 ◽

Vol 10 (5) ◽

pp. 379

Author(s):

Ziyi Liang ◽

Fuzhong Wu ◽

Xiangyin Ni ◽

Bo Tan ◽

Li Zhang ◽

...

Keyword(s):

Water Conservation ◽

Headwater Streams ◽

Regional Climate ◽

Plant Litter ◽

Alpine Forest ◽

Export Ratio ◽

New Findings ◽

Woody Litter ◽

Forest Streams ◽

And Storage

Headwater streams have low productivity and are closely linked to forest ecosystems, which input a large amount of plant litter into streams. Most current studies have focused on the decomposition process of plant litter in streams, and the effects of non-woody and woody litter on metal transfer, accumulation, and storage in streams are poorly understood. Here, we addressed how non-woody and woody litter affect metals in headwater streams in an alpine forest on the Eastern Tibetan Plateau. This area is the source of many rivers and plays an important regulatory role in the regional climate and water conservation. Through comparisons of five metal concentrations, exports and storage in headwater streams with different input conditions of plant litter, our results showed that the input of woody litter could significantly increase flow discharge and increase the metal export ratio in the water. Similarly, the input of non-woody litter could reduce the metal concentration in the water and facilitate the stable storage of metals in the sediment in the headwater streams. Therefore, allochthonous non-woody and woody litter can affect the concentration of metals in water and sediment, and the transfer and accumulation of metals from upstream to downstream in headwater streams. This study provides basic data and new findings for understanding the effects of allochthonous plant litter on the accumulation and storage of metals in headwater forest streams and may provide new ideas for assessing and managing water quality in headwater streams in alpine forests.

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Bark Stripping by Deer Was More Intensive on New Recruits than on Advanced Regenerants in a Subalpine Forest

Forests ◽

10.3390/f11050490 ◽

2020 ◽

Vol 11 (5) ◽

pp. 490

Author(s):

Takuo Nagaike

Keyword(s):

Coniferous Forest ◽

Regression Tree ◽

Cervus Nippon ◽

Subalpine Forest ◽

Bark Stripping ◽

Factors Affecting ◽

Subalpine Coniferous Forest ◽

Regression Tree Analysis ◽

Tsuga Diversifolia ◽

New Recruits

Research Highlights: To ensure sustainable forest regeneration, it is important to clarify whether new recruits or advanced regenerants are more likely to be stripped. Therefore, the effects of bark stripping on saplings in subalpine forests with abundant saplings should be analyzed by regeneration mode, but there have been no such studies until now. Background and Objectives: I investigated the effects of bark stripping by Cervus nippon on saplings in a subalpine coniferous forest in central Japan to (1) reveal differences in bark stripping between new recruits and advanced regenerants and (2) clarify the factors affecting survivorship. Materials and Methods: A 50 m × 140 m (0.7 ha) plot was set in the old-growth subalpine coniferous forest. All trees in the plot that were ≥2 m in height were tagged, identified to species, measured diameter at breast height and recorded bark stripping by deer. These trees and new recruits were counted and measured in 2005, 2007, 2012, and 2017. I compared saplings recruited in 2007, 2012, and 2017 (“new recruits”) with existing saplings of the same size (“advanced regenerants”). Results: The density of new recruits of Abies mariesii and Tsuga diversifolia increased, whereas that of Abies veitchii decreased. The proportion of stripped saplings was greater in new recruits than in advanced regenerants, significantly so in A. veitchii, which also had the highest maximum bark stripping ratio. Factors affecting the survivorships applied by the regression tree analysis were the maximum stripping ratio of stems for the two Abies species and the initial size for the T. diversifolia. Conclusions: Bark stripping by deer was more intensive on new recruits than on advanced regenerants in a subalpine forest, and regeneration in canopy gaps might fail because of intensive bark stripping in areas overabundant in deer.

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Phytophthora ramorum and Phytophthora gonapodyides Differently Colonize and Contribute to the Decomposition of Green and Senesced Umbellularia californica Leaves in a Simulated Stream Environment

Forests ◽

10.3390/f10050434 ◽

2019 ◽

Vol 10 (5) ◽

pp. 434

Author(s):

Kamyar Aram ◽

David M. Rizzo

Keyword(s):

Surface Waters ◽

Aquatic Ecosystems ◽

Litter Quality ◽

Phytophthora Species ◽

Phytophthora Ramorum ◽

Controlled Environment ◽

Green Leaves ◽

Umbellularia Californica ◽

And Function ◽

Forest Streams

Plant pathogenic as well as saprotrophic Phytophthora species are now known to inhabit forest streams and other surface waters. How they survive and function in aquatic ecosystems, however, remains largely uninvestigated. Phytophthora ramorum, an invasive pathogen in California forests, regularly occurs in forest streams, where it can colonize green leaves shed in the stream but is quickly and largely succeeded by saprotrophically competent clade 6 Phytophthora species, such as Phytophthora gonapodyides. We investigated, using controlled environment experiments, whether leaf litter quality, based on senescence, affects how P. ramorum and P. gonapodyides compete in leaf colonization and to what extent each species can contribute to leaf decomposition. We found that both Phytophthora species effectively colonized and persisted on green or yellow (senescing) bay leaves, but only P. gonapodyides could also colonize and persist on brown (fully senesced and dried) leaves. Both Phytophthora species similarly accelerated the decomposition of green leaves and yellow leaves compared with non-inoculated controls, but colonization of brown leaves by P. gonapodyides did not affect their decomposition rate.

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