Valley Forest Research Articles

小兴安岭5种林型土壤呼吸时空变异

Soil CO2 efflux(RS) is the second largest terrestrial carbon flux.Even a relatively small change in the carbon flow into,or out of,soils could have a large impact on atmospheric CO2 concentration.Conversion of forest ecosystems can potentially be a major contribution to greenhouse gas emissions.Therefore,reviewing measured rates and spatial and temporal variability of soil respiration from different terrestrial ecosystems and evaluating the effects of environmental factors and human disturbance on them provides essential data for the global carbon budget and its estimated effect on climate change.The representative disturbance gradient(virgin forest secondary forest plantation) in the Liangshui Nature Reserve of the Xiaoxing′an Mountains of Northeast China provides an excellent opportunity to examine how soil respiration responds to human disturbances.Throughout the growing season(May—October) in 2010,an infrared gas exchange analyzer was used to measure and compare soil respiration rates and related environmental factors in various forest systems.The forest systems investigated were virgin mixed broadleaved-Korean pine forest,valley spruce-fir forest,selectively cut mixed broadleaved-Korean pine forest,secondary birch forest and Dahurian larch plantation.The results showed that there was significant seasonal variation in soil respiration in the different forest types during the growing season where the peak soil respiration rate was in July and August and the lowest respiration rate was in the early and late growing season.There was a significant exponential correlation between soil respiration and soil temperature at 5 cm(T5) in the five forest types(P0.001).Furthermore,soil temperature and soil moisture and the interactions between them could explain 71% of seasonal variation in soil respiration,and incorporating soil moisture into the pure RS temperature model improved the prediction of RS in most forest types.The average soil respiration rates in the growing season for the birch,spruce-fir,selectively cut mixed broadleaved-Korean pine,mixed broadleaved-Korean pine,and larch forests were 3.59,3.52,3.44,2.58,and 2.29 μmolCO2 · m-2 · s-1,respectively and the corresponding Q10 values were 2.32,2.10,2.08,1.95,and 1.84.The average soil respiration rate of the mixed broadleaved-Korean pine forest was 33% and 28% lower than the secondary birch forest and selectively cut mixed broadleaved-Korean pine forest,respectively,but 12% higher than the larch plantation.This indicated that soil respiration responded differently to human disturbance in the mixed broadleaved-Korean pine forest.The standard deviation(SD) of RS for the six forest types showed a similar seasonal pattern to soil temperature where the mean SD of RS in the six forest types was 1.03 μmolCO2 · m-2 · s-1 between late June and early September and 0.51 μmolCO2 · m-2 · s-1 in the early and late growing season.The average coefficient of variation(CV) among forest types was 26.40%.The CV of soil respiration rate between replicates in each forest type varied from 32.13% to 60.20%,significantly greater than those between plots(14.28%—35.70%),indicating that soil respiration was more variable on the fine scale.The CV of RS between replicates in the mixed broadleaved-Korean pine forest and selectively cut mixed broadleaved-Korean pine forest(59.54% and 60.20%,respectively) were significantly(P0.05) greater than those in valley spruce-fir forest and Dahurian larch plantation(44.39% and 32.13%,respectively).Although spatial variations in soil respiration for all the forest types were not significantly related to soil temperature,soil moisture could explain about 15.8%—33.5% of spatial variation of soil respiration within each forest type except the mixed broadleaved-Korean pine forest.

Structural variation and content of aboveground living biomass in an area of Atlantic Forest in the State of São Paulo, Brazil

Knowledge of the vegetation structure in the Atlantic Forest is essential to support studies about its functioning, in view of broad interest issues such as global carbon balance. This study aimed to describe the structural variation in a heterogeneous area at Núcleo Santa Virgínia, Parque Estadual da Serra do Mar and how the aboveground living biomass is distributed in its phytophysiognomies. In each physiognomy studied, blocks of 10 × 10 m plots were allocated, totaling 0.6 ha of sampling. From the 1,046 individuals with PBH > 15 cm sampled, 443 were in riparian forest (RF), 272 in valley forest (VF) and 331 in hill forest (HF), with a total of 119 species. Shannon index was 3.63 and Pielou equability 0.76. Biomass estimated corresponds to 225.45 mg ha-1 (total), 193.6 mg ha-1 (RF), 299.85 mg ha-1 (VF) and 182.9 mg ha-1 (HF). The forest presents similar features to other fragments previously analyzed.

Tendencies for landscape-geochemical changes in valley forests of northern Western Siberia

The regularities of landscape-geochemical changes shared by open woodlands, and by the northern and middle taiga are demonstrated with an example of the swamping process of valley forests. The character of these changes is shown for forests on loamy and sandy deposits. The tendencies of the structural-functional transformations ascertained in this study are considered in the context of regional biogeochemical problems faced by the plain-taiga territory of Western Siberia.

Fossil wood of Bischofia palaeojavanica Awasthi from the Eocene of the Changchang Formation of Hainan Island, China

A fossil wood of Bischofia palaeojavanica Awasthi resembling the extant Bischofia javanica Blume of the family Euphorbiaceae, is described from the Eocene sediments of the Changchang Basin of Hainan Island, China. The fossil not only forms the first record of Bischofia from the basin, but is also the earliest from China. Its presence indicates the occurrence of humid valley forests in the region during the deposition of the sediments.

Canopy level fog occurrence in a tropical lowland forest of French Guiana as a prerequisite for high epiphyte diversity

Fog frequency and the meteorological processes leading to fog formation have never been studied in depth in tropical lowland forest areas. This study provides detailed evidence of frequent fog occurrence in lowland valleys of central French Guiana. Fog frequency showed a clear diurnal course, with a maximum before sunrise; average fog duration was 4.6 h. The diurnal course of visibility was positively correlated with the diurnal course of humidity in the above-canopy air. Fog persistence correlated significantly with atmospheric parameters during the dry season, but not during the rainy season. The main trigger of fog development in the lowland forest seemed to be precipitation, leading to higher soil moisture, greater evapotranspiration and, thus, higher water content of air. An increasing temperature difference between valley and hill sites after sunset, together with more frequent down-slope winds during nights with long fog periods, points at some influence of katabatic flows. The frequent occurrence of fog in the valleys correlated with significantly higher epiphyte diversities in valley forests as compared to hill forests, and supported the occurrence of the hitherto undescribed, epiphyte-rich “tropical lowland cloud forest” (LCF) in the valleys. The higher epiphyte diversity in LCF coincided with significantly higher relative air humidity in LCF than in hill forest. The ecological benefits of fog for the epiphytes in LCF are surplus of moisture and delayed onset of the stress period, particularly in the dry season.

Distribution of genets of Cylindrobasidium argenteum in a river valley forest as determined by somatic incompatibility, and the significance of basidiospores for its dispersal

Cylindrobasidium argenteum, a causal pathogen of white stem blight of a variety of broadleaf trees and shrubs, is thought to be transmitted to healthy trees through contact with infected branches of neighboring trees. To clarify whether basidiospores of C. argenteum are involved in the dispersal and infection process, we investigated distribution of genets of the fungus in a river valley forest using a somatic incompatibility test. Thirty-eight isolates were collected from diseased trees along two census lines at the bottom of Kikuchi River valley in southern Japan. In addition, 50 isolates were collected from four experimental plots on the slope of the valley. When the isolates from the valley bottom were paired in all combinations, a narrow clear zone line appeared in 701 out of 703 pairings, indicating that the material included 36 different genotypes, and suggesting that airborne basidiospores play an important role for dispersal of C. argenteum. In contrast, vegetative spread proved to be more frequent on the slope of the valley. On lower parts of such slopes, opportunities for healthy trees to meet infectious agents may increase because infected broken branches frequently move downwards on the slope. Based on these results, we suggest that C. argenteum adopts following dissemination strategies: (1) it spreads chiefly by basidiospores and infects trees, and (2) after colonizing stems or branches and producing an extensive mycelial mat, secondary infections of adjacent trees occur by contact with infectious agents such as diseased branches.

Patchiness in distribution of rodents and mustelids in New Zealand forests

Context. Relative density indices assuming uniform distribution of the target species are often the only cost-effective method for monitoring a population over the long term and at landscape scale, and the only source of valuable historical data. Yet, theoretical models emphasise the dangers of ignoring spatial heterogeneity, especially in short-term field data. Aims. To test whether Brown’s index of patchiness (BIP) can offer a simple means of checking rodent and mustelid survey data for violations of the assumption of uniform distribution. Methods. We use BIP to interrogate long-term legacy data collected by index trapping of mice (Mus musculus), rats (Rattus rattus and R. norvegicus) and stoats (Mustela erminea) in New Zealand forests. Key results. We found evidence of moderately patchy distributions that were independent of abundance in all three species. In two South Island beech (Nothofagus) forest valleys, 19% (6 of 31) of mouse samples and 8% (3 of 36) of stoat samples were significantly patchy, correlated with a seedfall event; in mixed forest at Pureora in the North Island, significant patchiness in distribution of ship rats was recorded in 19% (16 of 84) of Fenn trap samples and 5% (2 of 42) of rodent trap samples. Conclusions. Moderate patchiness is common. The consequences for any given study depend on the purpose of the work, but may be more important for practical management than for population modeling.

The Wadi Jawrah Mimusops Garden

The Wadi Jawrah Mimusops Garden is a new botanic garden which is under construction on a 25ha site in Jizan province, southern Saudi Arabia. The garden is being established around a stand of 14 Mimusops laurifolia (Forssk) Friis trees, the second largest stand of this species in the Arabian Peninsula. The major objectives of this garden are to conserve these trees, recreate the rare valley forest habitat of which they are characteristic, establish a nursery for the propagation and ecological restoration of rare species, and to provide a valuable resource for conservation education in the region. This paper covers these aims, the conservation importance of M. laurifolia and valley forest and some challenges and recommendations for the new garden.

ARABIA'S LAST FORESTS UNDER THREAT II: REMAINING FRAGMENTS OF UNIQUE VALLEY FOREST IN SOUTHWEST ARABIA

Over the last three decades, vegetation surveys in southwest Arabia have documented the existence of a small number of valley forest patches. A well-known area is in Wadi Rijaf, Jabal Bura, a protected area which has recently been surveyed by the current authors. The other valley forest sites in southwest Arabia have not been surveyed for over 15 years. This paper presents a descriptive study of five of these important valley forest localities. To provide an assessment of conservation value, field studies recorded the extent, quality and composition of the vegetation and the presence of regionally rare species. The significance of these remaining patches of Arabian forest, and the immediate threats to their survival, are also discussed.

Ethnobotany and phytomedicine of the upper Nyong valley forest in Cameroon

This paper presents the results of an assessment of the ethnobotanical uses of some plants recorded in upper Nyong valley forest implemented by the Cameroon wildlife conservation society project (CWCS). Forestry transects in 6 localities, followed by socio-economic study were conducted in 250 local inhabitants. As results, medicinal information on 140 plants species belonging to 60 families were recorded. Local people commonly use plant parts which included leaves, bark, seed, whole plant, stem and flower to cure many diseases. According to these plants, 8% are use to treat malaria while 68% intervenes to cure several others diseases as described on. There is very high demand for medicinal plants due to prevailing economic recession, however their prices are high as a result of prevailing genetic erosion. This report highlighted the need for the improvement of effective management strategies focusing on community forestry programmes and aims to encourage local people participation in the conservation of this forest heritage to achieve a sustainable plant biodiversity and conservation for future posterity. Key words: Conservation, ethnobotanical uses, diseases, posterity, Nyong valley.

Historical ecology of Inwood Hill Park, Manhattan, New York

Colonial period agriculture and vegetation clearance practices during the American Revolution destroyed the pre-Columbian forest of Inwood Hill Park, Manhattan, New York. Native species plantings in early estates spread to form the park's forest, and post-1850 estates introduced non-native species. Parks Department management practices from 1930 to 1985 reduced forest cover, filled wetlands, and caused the number of non-native and invasive shrub and vine species to nearly triple. Liriodendron tulipifera L. and Lindera benzoin (L.) Blume have been identified as the dominant species in the Valley Forest since 1930. Prunus serotina Ehrh., Sassafras albidum (Nutt.) Nees. and Viburnum acerifolium L. have continued to form fire-adapted stands in the East Ridge and Slopes Forest. In 2003, the highest density for Prunus serotina occurred in the repeatedly disturbed stands of the West Ridge and Slopes Forest. Alliaria petiolata (Bieb.) Cavara & Grande, an invasive species, was present only in the Ridge Tops Forest in 1985 and has become the dominant non-native herb species in all of the forests. The invasive shrub and vine species Celastrus orbiculatus Thunb., Lonicera japonica Thunb., L. maackii (Rupr.) Maxim., and Rosa multiflora Thunb. have become the dominants in the cleared areas of the Ridge Tops Forest. Sixteen woody invasive species are displacing native species across the park. Soil eroding into the salt marsh has caused the dominance of upland disturbance species. Replacing invasive species with native species has had mixed success because of limited funding to maintain plantings in the dry, impoverished soils of the park and areas treated with herbicides. Assessment methods for the restoration projects and for monitoring long-term species changes are recommended.

ARABIA'S LAST FORESTS UNDER THREAT: PLANT BIODIVERSITY AND CONSERVATION IN THE VALLEY FOREST OF JABAL BURA (YEMEN)

The isolated massif Jabal Bura (Yemen) is home to the largest area of ‘valley forest’ in southwest Arabia's western escarpment mountains. This study surveys the composition of this very rare forest and records the diversity of vascular plant species. It notes the valley forest as the home of several regionally rare species and records new locations for these taxa. A brief analysis of the canopy layer is provided, enabling comparisons with similar vegetation in northeast Africa. The paper discusses the importance of this regionally rare vegetation as well as threats to its conservation.

Sleeping Parties and Nest Distribution of Chimpanzees in the Savanna Woodland, Ugalla, Tanzania

We conducted ecological studies of chimpanzees (Pan troglodytes) in the Ugalla area, western Tanzania. Ugalla is one of the driest habitats of chimpanzees and the Ugalla River is the eastern boundary of chimpanzee distribution. Most of Ugalla is occupied by savanna woodlands dominated by deciduous trees of Brachystegia and Julbernardia. Chimpanzees tended not to make nests in riverine forests in plains, but in small patchy forests dominated by Monopetalanthus richardsiae and valley forests dominated by Julbernardia unijugata on slopes in mountainous areas. We estimated population density of chimpanzees to be 7–9 × 10−2 individuals/km2 based on nest censuses, suggesting that 2–3 × 102 individuals inhabited the 3352 km2 area of Ugalla. The size of the largest nest cluster (n=23) suggests that 1 unit group (community) comprised 30–35 individuals. In the daytime, chimpanzees formed small feeding parties (mean 2.0 individuals), but larger ones in the evening (mean 4.8 individuals and 5.2 individuals based on fresh nest clusters). The pattern might reduce the predation risk from large nocturnal carnivores such as lions and leopards. The sleeping sites may function as both a safe sleeping site and a meeting point for chimpanzees with a huge home range that may have difficulty in finding other members of their unit group.

Preceramic Adoption of Peanut, Squash, and Cotton in Northern Peru

The early development of agriculture in the New World has been assumed to involve early farming in settlements in the Andes, but the record has been sparse. Peanut (Arachis sp.), squash (Cucurbita moschata), and cotton (Gossypium barbadense) macrofossils were excavated from archaeological sites on the western slopes of the northern Peruvian Andes. Direct radiocarbon dating indicated that these plants grew between 9240 and 5500 (14)C years before the present. These and other plants were recovered from multiple locations in a tropical dry forest valley, including household clusters, permanent architectural structures, garden plots, irrigation canals, hoes, and storage structures. These data provide evidence for early use of peanut and squash in the human diet and of cotton for industrial purposes and indicate that horticultural economies in parts of the Andes took root by about 10,000 years ago.

Floristic Study of Ghasemloo (Shohada) Valley Forest Reserve and adjacent area

In this survey flora of protected region of Ghasemloo valley Forest reserve and adjacent areas has been studied. The study area includes about 577 ha and is located at south of Urmia. The method which used for plant collection is the same as regional floristic studies. Collected plants were recognized and determined as families, genera and species by using of indispensable references. Alphabetical list of taxa in this region was provided on the base of families, genera and species. The life form of plant species was determined by using of Raunckier's method and chorotype of plant species was determined by indispensable references. In this research 50 family, 165 genera and 204 species were identified. The largest plant family is Compositae with 21 genera and 26 species and the largest genera is Astragalus from Papilionaceae family with 6 species. The main biological forms respectively are: Therophytes and hemichryptophytes. The most extended chorotype with 61.28% is related to Irano-Turanian.

A new natricine snake of the genus Amphiesma (Squamata: Colubridae: Natricinae) from the central Truong Son, Vietnam

A new species of Amphiesma is described from the Truong Son (Annamite mountain range) of Quang Binh Province in central Vietnam. This new species is characterized by the combination of the distinct coloration and pattern, the slender body and tail (tail/total length ratio 0.31), the large eye diameter, a single loreal and preocular, three postoculars, a single anterior and posterior temporal, nine supralabials (fourth to sixth reach the eye), nine infralabials, 179 ventrals (plus two preventrals), anal plate divided, 99 divided subcaudals, dorsal scales in 19-19-17 keeled rows, 34 maxillary teeth (the two posteriormost enlarged), hemipenis simple, with undivided sperm groove, covered with small spines except for a single, strongly enlarged spine next to the sperm groove at the hemipenis base and except for irregularly arranged medium-sized spines that encircle the organ horizontally at the trunco-pedicel area. The new taxon is known only from a single male specimen that was collected in a limestone forest valley.

Spatial and temporal scale issues in determining biomass burning regimes in Bolivia and Peru

ATSR‐2 active fire data from 1996 to 2000, TRMM VIRS fire counts from 1998 to 2000 and burn scars derived from SPOT VEGETATION (the Global Burnt Area 2000 product) were mapped for Peru and Bolivia to analyse the spatial distribution of burning and its intra‐ and inter‐annual variability. The fire season in the region mainly occurs between May and October; though some variation was found between the six broad habitat types analysed: desert, grassland, savanna, dry forest, moist forest and yungas (the forested valleys on the eastern slope of the Andes). Increased levels of burning were generally recorded in ATSR‐2 and TRMM VIRS fire data in response to the 1997/1998 El Niño, but in some areas the El Niño effect was masked by the more marked influences of socio‐economic change on land use and land cover. There were differences between the three global datasets: ATSR‐2 under‐recorded fires in ecosystems with low net primary productivities. This was because fires are set during the day in this region and, when fuel loads are low, burn out before the ATSR‐2 overpass in the region which is between 02.45 h and 03.30 h. TRMM VIRS was able to detect these fires because its overpasses cover the entire diurnal range on a monthly basis. The GBA2000 product has significant errors of commission (particularly areas of shadow in the well‐dissected eastern Andes) and omission (in the agricultural zone around Santa Cruz, Bolivia and in north‐west Peru). Particular attention was paid to biomass burning in high‐altitude grasslands, where fire is an important pastoral management technique. Fires and burn scars from Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM) data for a range of years between 1987 and 2000 were mapped for areas around Parque Nacional Río Abiseo (Peru) and Parque Nacional Carrasco (Bolivia). Burn scars mapped in the grasslands of these two areas indicate far more burning had taken place than either the fires or the burn scars derived from global datasets. Mean scar sizes are smaller and have a smaller range in size between years the in the study area in Peru (6.6–7.1 ha) than Bolivia (16.9–162.5 ha). Trends in biomass burning in the two highland areas can be explained in terms of the changing socio‐economic environments and impacts of conservation. The mismatch between the spatial scale of biomass burning in the high‐altitude grasslands and the sensors used to derive global fire products means that an entire component of the fire regime in the region studied is omitted, despite its importance in the farming systems on the Andes.

Influence of logjam-formed hard points on the formation of valley-bottom landforms in an old-growth forest valley, Queets River, Washington, USA

Field surveys and radiocarbon dating of buried logjams in the floodplain of an old-growth forest river demonstrate the formation of erosion-resistant “hard points” on the floodplain of the Queets River, Washington. These hard points provide refugia for development of old-growth forest patches in frequently disturbed riparian environments dominated by immature forest. Our surveys show that local bed aggradation associated with logjams not only influences channel patterns and profiles but leads to development of a patchwork of elevated landforms that can coalesce to form portions of the valley bottom with substantial (i.e., 1 to >4 m) relief above the bankfull elevation. In addition, logjam-formed hard points promote channel avulsion, anastomosing morphology, and growth of mature patches of floodplain forest that, in turn, provide large logs needed to form more logjam-formed hard points. Hence, our findings substantiate the potential for a feedback mechanism through which hard points sustain complex channel morphology and a patchwork floodplain composed of variable-elevation surfaces. Conversely, such a feedback further implies that major changes in riparian forest characteristics associated with land use can lead to dramatic simplification in channel and floodplain morphology.

Characterization of a Forest Soil Metagenome Clone That Confers Indirubin and Indigo Production on Escherichia coli

A microbial community analysis of forest soil from Jindong Valley, Korea, revealed that the most abundant rRNA genes were related to Acidobacteria, a major taxon with few cultured representatives. To access the microbial genetic resources of this forest soil, metagenomic libraries were constructed in fosmids, with an average DNA insert size of more than 35 kb. We constructed 80,500 clones from Yuseong and 33,200 clones from Jindong Valley forest soils. The double-agar-layer method allowed us to select two antibacterial clones by screening the constructed libraries using Bacillus subtilis as a target organism. Several clones produced purple or brown colonies. One of the selected antibacterial clones, pJEC5, produced purple colonies. Structural analysis of the purified pigments demonstrated that the metagenomic clone produced both the pigment indirubin and its isomer, indigo blue, resulting in purple colonies. In vitro mutational and subclonal analyses revealed that two open reading frames (ORFs) are responsible for the pigment production and antibacterial activity. The ORFs encode an oxygenase-like protein and a putative transcriptional regulator. Mutations of the gene encoding the oxygenase canceled both pigment production and antibacterial activity, whereas a subclone carrying the two ORFs retained pigment production and antibacterial activity. This finding suggests that these forest soil microbial genes are responsible for producing the pigment with antibacterial activity.

Mollusc fauna of the Rychlebské Hory (Czech Republic)

120 mollusc species (50 % of the Czech Republic mollusc fauna) were recorded from the Rychlebske Hory (Czech Republic, Silesia), as a result of the recent malacological research of 33 sites, combined with earlier published and unpublished data. The most diverse communities were those of forest valleys and old limestone quarries. New isolated sites of Helicella itala (the easternmost occurrence) and Chondrina clienta were found. Based on the revision of Helicellinae species of this region we think that Cernuella neglecta should be deleted from the list of Polish gastropods. The previous single record was a result of confusion with Helicella itala.