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Δευτέρα 27 Μαΐου 2019

Acta Ecologica Sinica

Evaluating soil biochemical/microbial indices as ecological indicators of different land use/cover in northern Iran

Publication date: Available online 25 May 2019

Source: Acta Ecologica Sinica

Author(s): Negar Moghimian, Seyed Mohsen Hosseini, Yahya Kooch, Behrouz Zarei Darki

Abstract

The objective of the study was to examine changes in microbial parameters have been used to monitor changes in soil quality under different land uses in north of Iran. The microbial parameters included microbial respiration (MR), substrate induced respiration (SIR), carbon availability index (CAI), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), ratio of MBC/MBN, metabolic quotient (qCO2) and microbial ratio were determined under different land use/cover, i.e. virgin natural forest (VNF), degraded natural forest (DNF), alder plantation (AP), sequoia plantation (SP), improved fallow (IF) and home garden (HG) areas in northern Iran. Five composed samples per land use/cover were taken from the top 10 cm of the soil. MR and SIR (0.45 and 1.66 mg CO2-C g−1 day−1, respectively) were found to be significantly higher under AP land uses than in the other areas. CAI did not differ for the land uses; MBC (591 and 590 mg kg−1, respectively) had higher significantly under SP and VNF land uses than in the other areas. MBN (64.25 and 62.33, respectively mg kg−1) was significantly higher in AP and VNF land uses, ratio of MBC/MBN (17.02) was higher in SP land use than other areas, HG had significantly higher qCO2 (0.0012 μg CO2-C mg−1 MBC day−1) and finally microbial ratio was significantly higher under IF (599.16) in comparison with HG > AP ≈ DNF > VNF > SP areas. Overall, our results indicate that AP land use (Alnus subcordata C. A. Mey.) increase of soil quality and alder plantation is suitable for rehabilitation of degraded natural forests.



Floristic inventory and biological spectra of Balakot, District Mansehra, Pakistan

Publication date: Available online 25 May 2019

Source: Acta Ecologica Sinica

Author(s): Muhammad Asif, Zafar Iqbal, Jan Alam, Abdul Majid, Farhana Ijaz, Niaz Ali, Inayat Ur Rahman, Sadam Hussain, Anees Khan, Ghulam Qadir

Abstract

This study was conducted to assess the floristic composition, biological spectra and phenology of Tehsil Balakot. Frequent visits were made in different seasons during 2012–13. Field notebook was used to record the data within field. Biological spectrum and leaf sizes classes were determined. The floristic diversity revealed 228 plant species belonged to 184 genera and 72 families. Asteraceae family contributed maximum number of species (27) followed by Rosaceae (18), Apiaceae and Lamiaceae (12) species each, Papilionaceae (11) species while remaining 67 families contributed less than 10 species. Herbaceous growth form was the most leading one (71%), followed by shrub (15%) and tree (14%), respectively. Biological spectrum revealed that hemicryptophytes (32.45%) were the most prevalent, followed by therophytes (31.57%), nanophanerophytes (15.35%), megaphanerophytes (13.59%) and chamaephytes (4.38%). Leaf spectra showed that microphyll (28.94%) were dominant, followed by nanophyll (27.19%), leptophyll (22.80%), mesophyll (14.03%) and megaphyll (7.01%). The flora was influenced by two flowering seasons i.e. March to August and September to February. In the first spell, 193 species were recorded, of these 15.54% trees, 15.02% shrubs, 63.21% herbs, 3.62% grasses and 2.59% ferns; while in the second spell, there were 35 species having 2.85% trees, 17.14% shrubs, 74.28% herbs, and 5.71% grasses. The flowering data shows that June and July were the utmost flowering months with 28.50% in 65 and 20.17% in 46 plant species.



Relationship between topography and the distribution of matorral plant species in the Saharan Atlas: Case of Djebel Amour, Algeria

Publication date: Available online 24 May 2019

Source: Acta Ecologica Sinica

Author(s): Mostafa Naceur Youcefi, Mustapha Daddi Bouhoun, Abdellah Kemassi, Mohamed Didi Ould El-Hadj

Abstract

One of the primary goals in community ecology is to determine the relative importance of processes and mechanisms that control biodiversity. The reduced coverage of vegetation and the severe losses of biodiversity in semiarid matorrals have recently become serious concerns in the Saharan Atlas in southern Algeria. In terms of research, the control of the spatial distribution of vegetation by the topographic factors has not received the attention it merits in Djebel Amour's region. This study combined several multivariate analyses to assess quantitatively the extent and nature of the topographic influence on the distribution of matorral plant species. Thirty plots (20 m × 20 m) were selected according to their physiognomy for the field survey of vegetation and topography in a semiarid mountainous region. The distributions of vegetation differed significantly amongst topographies, indicating different environmental conditions and determine a turnover of important species. Most species colonize downslopes, and only some persist on steep-slopes and summits. The low coverage of vegetation (36.98%) on steep-slopes was due to the serious soil erosion and rockiness 66.5–83.1%. The low average richness in summits (39.67) was due to elevation and negative effect of trees. Elevation, then rockiness and slope were respectively the main topographic factors influencing the distribution of matorral plants. The relationship between topography and distribution could be described by a linear model. Seventeen linear models were built for eleven floristic variables with three topographic factors, elevation, rockiness and slope explained 26–83% of the variance in distribution, also four groups of plant species were listed according to topographic positions. The suitability of plant species to the topographic factors should be considered in the restoration of matorrals in the study area. The results of this study will be useful for selecting the appropriate species and the potential sites for seeding to improving damaged matorral ecosystems in this area. However, additional investigations on soils, water availability and microclimate are required to clarify the mechanism of distribution of plant species in these ecosystems.



Effects of hexane extract of Lantana camara leaves on reproductive bioactivities of Dysdercus koenigii Fabricius (Heteroptera: Pyrrhocoreidae)

Publication date: Available online 24 May 2019

Source: Acta Ecologica Sinica

Author(s): Sunil Kayesth, Shailendra Kumar, Mohd Shazad, Kamal Kumar Gupta

Abstract

Effects of hexane extract of Lantana camara leaves were investigated on reproductive bioactivities of Dysdercus koenigii by assessing mating behavior, oviposition behavior and fertility of the adults emerged from treated fifth instar nymphs. Leaves of L. camara were extracted in hexane by 'cold extraction method'. The fifth instar nymphs were treated with the extract by 'dry film residual method' for 24 h and the adults emerged from these nymphs were used for the experiments. The results indicated that treated males showed altered courtship behaviour, lesser number of mounting attempts and took relatively more time to mate than the normal males. The treated females, very often, exhibited mating refusal and non-receptive behaviour towards the courting males. This led to decrease in percent successful mating. Also, the mating in the treated insects frequently got disrupted and terminated prior to insemination. The treatment of the females with the extract resulted in alteration of their oviposition behaviour. Consequently, the treated females laid lesser number of egg batches and total number of eggs in their life span. Although the eggs laid by the treated females were fertile, the percent hatchability was lesser than normal. The results signify that hexane leaf extract of Lcamara possesses phytochemicals, which adversely impaired the reproductive bioactivities of D. koenigii. Therefore, some of these compounds individually or synergistically can be employed in integrated pest management of D. koenigii by hampering its reproductive potential.



Using water and energy variation to explain the botanical richness pattern of Theaceae species in southern China

Publication date: Available online 24 May 2019

Source: Acta Ecologica Sinica

Author(s): Ming-Gang Zhang, Xia-Yun Zhao, Li-Jun Liu, Chen-Yu Huang

Abstract
Background

Energy and water availability are essential for biodiversity maintenance. In addition to the independent effects of water and energy on biodiversity, recent studies clarified that the effects of interaction between water and energy availability were indispensable.

Methods

In this exercise, by combining the species presence information and the environmental predictors, we produced species distribution models at 20 × 20 arc-minute resolution for 193 Theaceae species. Initially, the ordinary least square (OLS) regression was used to examine the stationary relationships between Theaceae diversity and climate. The statistical effects of water and energy on species diversity were detected using Geographically Weighted Regression analysis (GWR). Furthermore, the contour plots were used to view the statistical effects of the water and energy interaction on species diversity.

Results

The OLS results suggested that both energy and water availability are related to Theaceae species diversity. In GWR regression, the spatial variation of energy and water showed high explanatory power to the diversity pattern of Theaceae species. The patterns in the residuals of both OLS and GWR regression varied geographically. Therefore, the results of GWR regression were kept for further analysis. The value of diversity-water slopes decrease changed from positive to negative in extremely wet regions; In extremely dry conditions, the value of diversity-energy slopes decrease faster than other regions.

Conclusions

Our results support the following findings: 1) the latitudinal distribution of Theaceae species was limited by thermal tolerance, which support the freezing-tolerance hypothesis in macro-ecology; 2) Theaceae species diversity are sensitive to the instability of precipitation, while the limitation from energy availability is weak; 3) the effects of water and energy on species diversity are strong in dry regions. Those findings can provide further implications for Theaceae species conservation under climate change scenarios.



Species diversity, biological spectrum and phenological behaviour of vegetation of Biha Valley (Swat), Pakistan

Publication date: Available online 23 May 2019

Source: Acta Ecologica Sinica

Author(s): Akber Zeb, Zafar Iqbal, Shujaul Mulk Khan, Inayat Ur Rahman, Faizul Haq, Aftab Afzal, Ghulam Qadir, Farhana Ijaz

Abstract

A study was conducted to explore the plant biodiversity, phenology, life form and leaf size spectra of the vegetation of Biha Valley, District SWAT. The study area was surveyed thoroughly in different seasons of the year. Floristic diversity of the area consists of 202 plant species belonging to 154 genera and 70 families. There were two flowering seasons, 85.15% plant species flowers during May to August while 14.65% plant species flowers during the September to November. Biological spectrum of the area indicated that Therophytes (46.60%) was the dominant life form class, followed by Hemicryptophytes having 15.53%, Nanophanarophytes (11.65%), Megaphanerophytes (8.25%), Chamaephytes (7.77%), Geophytes (5.34%), Liana (2.91%) and Mesophanarophytes (1.94%). Leaf spectra of study area revealed that Microphylls was dominant with (41.26%) followed by Nanophylls (32.04%), Mesophylls (15.53%), Leptophylls (8.85%) and Megaphylls (2.91%).



Soil carbon stocks in plantations and natural forests of the sub-tropics

Publication date: Available online 23 April 2019

Source: Acta Ecologica Sinica

Author(s): Lu Shunbao, Xu Yan, Fu Xiangping, Zhang Yanjie

Abstract
Purpose

Soil carbon (C) storage plays an important role in the mitigation of atmospheric CO2 emission. Soil C pools under different vegetation are distinct and need to be investigated. However, there are still large quantities of data shortages, which should be remedied by field and systematic studies.

Materials and methods

Soil was collected at 0–10 cm depth from subtropical natural vegetation and plantations both in southeast China and southeast Queensland, Australia, respectively. Soil samples were assayed for soil organic C; organic N and inorganic N; and mineralization of SOC; total C, N, and P; and pH.

Results and discussion

Our results suggested soil C concentrations in natural vegetation ranged from 6.25% to 9.20%, whereas soil C concentrations in plantations ranged from 1.08% to 2.69%. No significant differences were found among vegetation along altitudinal gradients, whereas plantations with different tree species had different soil C concentrations, being higher in broadleaf-species plantations than in coniferous-species plantations. But there were no differences in soil C between single-species plantations and mixed-species plantations. Soil C concentrations in plantations were correlated with soil moisture, soil pH and dissolved organic C concentrations; Whereas soil C concentrations in natural vegetation were significantly correlated with soil moisture, soil pH and NO3 concentrations.

Conclusions

These results can contribute to the remedy of data shortages and provide the data necessary for model projections and informed decisions in the future.



Integration of Allelopathy and herbicide to control Asphodelus tenuifolius in chickpea crop

Publication date: April 2019

Source: Acta Ecologica Sinica, Volume 39, Issue 2

Author(s): Imtiaz Khan, Muhammad Ishfaq Khan, Hashmatullah

Abstract

Controlling Asphodelus tenuifolius in chickpea crop is a big challenge for the grower in the southern districts of Khyber Pakhtunkhwa-Pakistan. Keeping in view the yield losses due to weeds a research was conducted at Ahmadwala Research Station "District Karak" to control to A. tenuifolius. Herbicides, mulches and allelopathic weed extracts were evaluated during the experiment. The experiment was repeated thrice using Randomized Complete Block design with Chattan cultivar. The weed control treatments Viz. Stomp 330 EC (Pre) @ 2.5 L ha−1, Fenoxaprop-p-ethyl, Bromoxynil +MCPA (Tank mixture of herbicides), Starane-M, Eucalyptus leaves as mulch, wheat straw as mulch, allelopathic extract (Asphodelus tenuifolius) + Stomp, allelopathic Cyperus rotundus extract, allelopathic Sorghum halepense extract were tested and compare with the control treatment during the experiment. The data was recorded on A. tenuifolius density m−2 before and after treatment application, plant height, crude protein, crude fats, biological yield, and seed yield. The level of significance of all the treatments was (0.05). The results indicated that the minimum A. tenuifolius density was recorded in the plots treated with Stomp 330 EC (4.74 m−2) followed by herbicide Fenoxaprop-p-ethyl 6.9 EC (10.87 m−2). The maximum A. tenuifolius density was found in the control plots (81.64 m−2) which were left undisturbed. Among the chickpea yield components, the maximum plant height at maturity (48.98 cm) was recorded for Stomp 330 EC the lowest plant height was recorded for control plot. The maximum crude protein (17.68), crude fat (2.93) and oil content was (5.92%) was recorded in the plots treated with Stomp 330 EC and the minimum was found in the control plots. Similarly, the maximum biological yield (4058.7 kg ha−1) and seed yield (1282 kg ha−1) were recorded in Stomp 330 EC treated plots as biological and grain yield was observed for control plot. Therefore, it is recommended that using herbicides Stomp 330 EC and Fenoxaprop-p-ethyl is one of the effective weed control strategies for control of A. tenuifolius in chickpea growing areas.



Fungi infecting Escobaria cubensis and Melocactus holguinensis (Cactaceae) in northeastern Cuba

Publication date: April 2019

Source: Acta Ecologica Sinica, Volume 39, Issue 2

Author(s): Alena Reyes-Fornet, Elena Balbina Fornet Hernández, Yania Raquel Martínez Ondaro

Summary

Escobaria cubensis (Britton & Rose) D.R. Hunt and Melocactus holguinensis Areces (Cactaceae) are valuable Cuban natural heritage plants from ophiolite (serpentine) soils that are in Critical Danger of extinction. The in situ study on E. cubensis was conducted in Matamoros and that of M. holguinensis in La Ceja between May 2017 and July 2017, both in Holguín province. Samples in ex situ collections were also taken. The appearance of fungi somatic and reproductive structures was induced through wet chamber technique and isolation. Fungi were identified using taxonomic keys. Symptoms in E. cubensis consist of rotten soft roots, while M. holguinensisdisplays yellow spots followed by brown to blackish lesions with brown centers. Cacti death is the result of those infections. Pathogenicity tests showed that in E. cubensis, the fungi responsible for the symptoms are Fusarium oxysporum Schltdl. (or a complex), Colletotrichum gloeosporioides (Penz.) Penz. & Sacc and Penicillium sp. In M. holguinensisC. gloeosporioides causes the witnessed anthracnose in stems in both habitats. These fungi constitute a severe threat in natural habitat more for M. holguinensis than for E. cubensis. Results suggest that roots are the most vulnerable part of E. cubensis and stems appear to be more sensitive in M. holguinensis. C. lunata can infect both cacti, but no symptoms of illness have been seen either in situ or ex situ. Infection similarities seen both in nature and in collections could be because of inappropriate horticultural practices. Other fungi found are Aspergillus fumigatus Fresenius, A. niger van Tieghem, Cephalosporium sp., Cladosporium sp., Rhizopus sp. and Trichoderma sp. All fungi found in this study are new records for both hosts in Cuba. The results of this research allow to solve problems found in natural habitat and in ex situ collections. In addition, results suggest to collectors not to remove and use soil from the natural habitat, unless it is properly sterilized.



Assessment of density area and LNRF models in landslide hazard zonation (Case study: Alamout watershed, Qazvin Province, Iran)

Publication date: April 2019

Source: Acta Ecologica Sinica, Volume 39, Issue 2

Author(s): M. Eslami, S. Shadfar, A. Mohammadi-Torkashvand, E. Pazira

Abstract

Landslide is one of the natural disasters causing both life loss and financial damage. To plan and manage landslides better, it is necessary to produce landslide hazard zonation (LHZ) maps. Alamout watershed is one of the most susceptible landslides located in a mountainous area in north of Iran. At first, required information of layers such as geology, soil, elevation, slope, aspect, rainfall, and distance to fault, road, river, and land use factors from different sources were provided. Landslide inventory map was prepared using geological map, aerial photos and filed investigation with GPS. The map of each effective factor on the landslide was combined with the landslide distribution map to determine the weight of each factor. Landslide hazard zonation map was prepared with density area and LNRF methods in the Geographic Information System (GIS). The two models were evaluated with quality sum (Qs). Results showed that the density area method (Qs= 1.496) was more accurate than the LNRF model (Qs= 0.897). The results obtained from density area model indicated that very high hazard zones were approximately 33% of the study area. Additionally, low and very low hazard zones were almost 6.8% of the watershed. In the LNRF model, very low and low hazard zones were approximately 28% and high and very high hazard zones were 48% of the studying region.



Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
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