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STRUCTURAL ANALYSIS OF THE ARBOREAL COMPONENT OF THREE AREAS OF SAVANNAH IN DIFFERENT STADIUMS OF CONSERVATION, IN TRêS MARIAS COUNT, MINAS GERAIS STATE, BRAZIL.
Rubens Manoel dos Santos,Fábio de Almeida Vieira
CERNE , 2005,
Abstract: This research analyzed the floristic and the arboreal community's component of three savannah fragments structure in different conservation stadium to observe if substitution of species exists, in agreement with the degree of the arboreal community's preservation, in Três Marias Count, Minas Gerais. In the three areas MA (18o 18`02`` S and 45o 14`64`` W), LI (18o 17`05``S and 45o 14`13`` W) and TO (18o 12`46`` S and 45o 14`43`` W) were sampled 463 individuals, distributed into 63 species, 56 genera and 32 families, with prominence for the family Fabaceae with 13 species. The number of species sampled varied from 21 in MA, 29 in LI to 38 in TO. Of all the species sampled only four (6.5%) Qualea parviflora, Machaerium villosum, Magonia pubescens and Astronium fraxinifolium occurred in all the sampled areas. However, 39 species (63%) occurred in only one area. This is proven by DCA, where axis one synthesized 66% and the axis two synthesized 12% of data variation. This demonstrates the great substitution of species in elapsing of the succession stages, where LI and TO shared 14 (26.4%) of the 53 species sampled in these areas. LI and MA shared 5 species (11%) of the 46 species sampled in these two areas. TO and MA already shared 11 species (23%) of the 48 species sampled in these areas. These results demonstrate that, in spite of the long period of anthropic intervention, these areas are recovering their vegetal cover and maintaining the diversity characteristic of the biome where they are inserted.
Response of plant species to abandonment of subalpine fields, Manang, Nepal
Chitra Bahadur Baniya
Botanica Orientalis: Journal of Plant Science , 2011, DOI: 10.3126/botor.v8i0.5553
Abstract: Spatial dimension of abandoned fields has been expanding more in rural subalpine zones of Nepal leading to various patterns of secondary succession. The secondary succession in the subalpine Himalayas has not yet been evaluated. Here, I describe a study initiated in Manang district, Central Nepal where enough abandoned fields of different chronosequences were located. A definitive successional pattern was predicted from the data obtained from sampling 256 plots of 1 × 1 m 2 ？each systematically in a total of 43 abandoned fields from 1 to 55 years after abandonment. Change in composition pattern of 11 most important plant species was analyzed through the Detrended Correspondence Analysis (DCA). The first two axes of DCA explained 19.1 % of the total variation in the species composition. Early, mid and late successions were three stages distinguished each by their abundance scores and life-forms composition. Malva neglecta, Phleum alpinum and Fagopyrum esculentum were dominant at the recently abandoned fields. Cynoglossum zeylanicum, Malaxis muscifera, Medicago falcata and Pennisetum flaccidum were mid succession species, and Thymus linearis, Tanacetum gossypinum , Pinus wallichiana and Poa annua represented the late succession species. doi: http://dx.doi.org/10.3126/botor.v8i0.5553 Botanica Orientalis – Journal of Plant Science (2011) 8: 10-15
Estudo fenológico em três fases sucessionais de uma floresta estacional decidual no município de Santa Tereza, RS, Brasil
Andreis, Cáren;Longhi, Solon Jonas;Brun, Eleandro José;Wojciechowski, Júlio César;Machado, Ant？nio Augusto;Vaccaro, Sandro;Cassal, Christian Zago;
Revista árvore , 2005, DOI: 10.1590/S0100-67622005000100007
Abstract: the present study was accomplished in forty permanent plots belonging to three forest successional stages, denominated: brush forest, secondary forest and mature forest, in a seasonal deciduous forest in the municipal district of santa tereza, rs, brazil. phenologic observations were accomplished fortnightly for 53 arboreal species, in an average of 8,4 individuals per species, during the period of november 2001 to november 2002. the stages observed were flowering, fruiting and foliage change. the results indicate that the reproductive activity remained relatively low for three successional stages during the observed period, with a tendency to be even lower during winter. the total amount of leaves on the trees, regardless of the successional stage, decreased from approximately 85%, in the period of higher vegetative activity, to 35% in the winter, resting season. the mature forest maintained the largest percentage of leaves during the studied period.
Presence of large and medium-sized mammals in a burned pine forest in southwestern Turkey
Anil Soyumert,Cagatay Tavsanoglu,Oksal Macar,Burcin Yemisei Kainas
Hystrix : the Italian Journal of Mammalogy , 2010, DOI: 10.4404/hystrix-21.1-4488
Abstract: Riassunto Presenza di grandi e medi mammiferi in pinete incendiate della Turchia sud-occidentale Nel periodo Novembre 2005-Agosto 2006, è stata verificata, tramite trappole fotografiche, la presenza di mammiferi di grandi e medie dimensioni in foreste di Pinus brutia integre e incendiate della Turchia sud-occidentale. Sono state ottenute fotografie di tre specie, cinghiale (Sus scrofa), volpe (Vulpes vulpes) e faina (Martes foina). Le prime due sono state rinvenute in entrambe le aree, mentre la faina è stata accertata solo in boschi incendiati. I risultati del presente studio suggeriscono che gli stadi successionali intermedi successivi ai roghi possono essere ricolonizzati dalle comunità di mammiferi. doi:10.4404/hystrix-21.1-4488
不同演替阶段森林土壤酶动态研究进展
Research Progress of Forest Soil Enzyme Dynamics in Different Succession Stages  [PDF]
王浩, 王庆贵
International Journal of Ecology (IJE) , 2021, DOI: 10.12677/IJE.2021.101006
Abstract:
土壤酶作为森林生态系统的重要组成部分之一，主要来自于微生物，森林土壤酶活性是评价土壤质量和土壤生物群落的指标，而酶活性作为反映土壤生态系统功能的敏感指标，会随着土壤养分状况的改变而迅速发生变化。同时土壤酶的活性具有巨大潜力，可以对土壤进行独特的综合生物学评估以及评价土壤生物的健康状况，但目前对于不同演替阶段的土壤酶动态的研究相对较少。主要对不同演替阶段进行了研究，讨论了演替前期、演替中期以及演替后期相关土壤酶，例如β-葡萄糖苷酶(β-glucosidase, BG)、纤维素酶(Cellulase, CBH)、N-乙酰-β-氨基葡萄糖苷酶(β-N-acetyl-glucosaminidase, NAG)、亮氨酸氨基肽酶(Leucine amino peptidase, LAP)、酸性磷酸酶(Acid phosphatase, AP)、碱性磷酸酶(Alkaline phosphatase, ALP)等酶活性的变化，探究其变化的原因，以期为北方森林不同演替阶段土壤酶的研究提供支持。
Soil enzymes are considered to be one of the important components of forest ecosystem, mainly from microorganisms. Forest soil enzyme activity is used as an index to evaluate soil quality and soil biological community. The enzyme activity is used as a sensitive indicator reflecting the function of the soil ecosystem, and it will change rapidly as the soil nutrient status changes. At the same time, the activity of soil enzymes has great potential, which can carry out unique comprehensive biological assessment of soil and evaluate the health of soil organisms. However, there are relatively few studies on soil enzyme dynamics at different successional stages. This paper mainly studies the different succession stages, discusses the related soil enzymes in the early, middle and late succession, for example, the changes of β-glucosidase (BG), cellulase (CBH), N-acetyl-β-glucosidase (NAG), leucine aminopeptidase (LAP), acid phosphatase (AP), alkaline phosphatase (ALP), etc. to explore the reasons for the changes in order to provide support for the study of soil enzymes in different successional stages of northern forests.
Carabid beetle diversity and mean individual biomass in beech forests of various ages
Lucija ？eri？ Jelaska,Vlatka Dumbovich,Mladen Kucinic
ZooKeys , 2011, DOI: 10.3897/zookeys.100.1536
Abstract: Carabid beetle diversity and mean individual biomass (MIB) were analysed in three different successional stages of beech tree stands (60, 80 and 150 years old). Carabid beetles were captured using pitfall traps placed at nine sites (three per age class) in the Papuk Mountain of East Croatia during 2008. A cluster analysis identified three groupings that corresponded to the beech age classes. MIB values increased with stand age, ranging from 255 in 60-year-old stand to 537 in the oldest forests. The 80-year-old stand showed the highest species richness and diversity values. With respect to species composition, large species such as Carabus scheidleri and Carabus coriaceus were dominant only in the oldest forests. Furthermore, species that overwinter in the larval stage were more abundant in the oldest forests (45% of the total number of individuals from the 150-year-old stand) than in the younger ones (20% of individuals from 60-year-old, and 22% of individuals from 80-year-old stands). Our results showed that the analyses of species composition and life history traits are valuable for estimating the conservation values of older forests. Although the investigated sites form part of a continuous forested area and are only a couple of kilometres apart, MIB values detect significant differences associated with forest age and can be a useful tool in evaluating the degree to which a forest reflects a natural state.
Differentiation of Soil Variables in Different Succession Stages of Biological Soil Crusts in Gurbantunggut Desert,Northern Xinjiang,China
生物结皮恢复过程中土壤生态因子分异特征
WU Nan,ZHANG Yuan-ming,ZHANG Jing,WANG Hong-ling,NIE Hua-li,CHEN Rong-yi,
吴 楠,张元明,张 静,王红玲,聂华丽,陈荣毅
中国沙漠 , 2007,
Abstract: The present paper mainly dealt with the response of soil variables to biological soil crust succession in Gurbantunggut Desert.The result showed that soil variables obviously changed with the recovery time of biological soil crust.Variance analysis of Between-Subjects Effect showed that the recovery time significantly influenced the quantitative distributions of actinomyces and fungi.ANOVA analysis indicated that the content of total P,total K,organic matter,activity of urease,quantity of fungi significantly differed from each other in different succession stages of biological soil crusts(P<0.01).The content of available P,available K,total N,total salt,and activity of alkaline phosphatase,phosphatase and proteinase were influenced(P<0.05) by recovery time of biological crusts.Although the concentration of nutrient content and the activity of soil enzyme were both increased during the recovery process,pH value decreased in both surface 0~2 cm crust layers and 2~5 cm soil layers.Twelve years after removal of biological crusts,the nutrient and soil enzyme mainly accumulated in 0~2 cm crust layers.The results also showed that there was an obvious negative linear correlation between pH value and soil organic matter(R2=0.701,P<0.05).The electric conductivity,activity of urease,alkaline phosphatase,phosphatase and proteinase had distinct positive linear correlation with soil organic matter(R2=0.888,0.993,0.958,0.948,0.911 respectively,P<0.01).
Characteristics of the soil seed banks and relationships with the vegetation in restored wetlands in Sanjiang Plain, northeast of China
三江平原恢复湿地土壤种子库特征及其与植被的关系
WANG Guo-Dong,L Xian-Guo,JIANG Ming,WANG Ming,ZHAO Kui-Yi,LOU Yan-Jing,
王国栋,吕宪国,姜明,王铭,赵魁义,娄彦景
植物生态学报 , 2012,
Abstract: Aims Seed banks are an important source of regenerative material in wetlands. Our objective was to study characteristics of the soil seed banks and relationships with the vegetation in different restoration successional stages. Methods We collected soil seed banks from different depths (0–5 cm, 5–10 cm and rhizomes) from farmed wetland, restored wetland in different successional stages and natural wetland and germinated them under two water regimes (flooded and non-flooded) in a greenhouse. We used quadrats to survey vegetation structure in natural wetland and restored wetlands of different successional stages. Important findings With increased the restoration time, seed bank composition and size increased, and the vegetation community showed succession from a xerophyte-dominated community to a wetland community dominated by Calamagrostis angustifolia. Number of species germinated from the seed banks was 24, 29 and 39, while 21, 25 and 14 species were recorded in the vegetation of in 7-year restored wetland, 14-year restored wetland and natural wetland, respectively. Wetland type, water regime, depth of burial significantly influenced both the species richness and seedling emergence (p < 0.01). Seed density varied with depth so that seed density was higher in 0–5 cm than in 5–10 cm. The seed density in 0–5 cm was four times as that in 5–10 cm in natural wetland while it was just 1.3 times in restored wetland. The similarity between layers was low. More species germinated under non-flooded condition than flooded and the life forms differed. Because the restoration time was short, the similarity between seed bank and vegetation in different restoration successional stages was always <30%. Many wetland species germinated from rhizome fragments, especially C. angustifolia and other wetland species. Our research suggests that the seed bank could retain and restore several wetland species in different restoration successional stages, which can be valuable for vegetation succession and wetland restoration.
A STUDY ON THE SOIL SEED BANKS AT THE DIFFERENT SUCCESSION STAGES OF SOUTH SUBTROPICAL FORESTS
南亚热带森林不同演替阶段土壤种子库的初步研究
Huang Zhongliang,Kong Guohui,Wei Ping,Wang Junhao,Huang Yuji,Zhang Youchang,
黄忠良,孔国辉,魏平,王俊浩,黄玉佳,张佑昌
热带亚热带植物学报 , 1996,
Abstract: Soil seed banks at four succession stages of southsubtropical forests (Pine forest,Pine and broad-leaf mixed forest, young monsoon evergreen broad-leaf forest and mature monsoon evergreen broad-leaf forest) in Dinghushan Nature Reserve, Guangdong Province,were investigated. Four quadrates (1m× 1m each) were measured three times (one was in dry, one in rainy season, another was before rainy season) for each stages, and three soil stratifications were sampled for each quadrate. The soil samples were set in laboratory under sufficient humidity and nature sunlight, and seed gendnation was noted daily. The results showed that the number of seeds in the soil seed banks decreased with the development of forest succession, but the species diversity increased. The number of seeds and the species diversity were both higher in rainy season than in dry season. The number of seeds in the stratification at 3-5cm depth was almost the highest as compared with other stratifications.According to a regression analysis, species composition in the soil seed banks was less related to that on the ground vegetation. The seeds of herb species were dominant, but a few dominant species of ground vegetation were not found in the soil seed banks because of the short life of some seeds and eating by animals. The germination of seeds in the soil seed banks was more closely related to temperature than to humidity. The roles of soil seed banks in forest succession were discussed.
Learning to Cope with Trauma and Moving Forward  [PDF]
Connie Taute
Psychology (PSYCH) , 2023, DOI: 10.4236/psych.2023.146055
Abstract: Stages to processing trauma are basically nonexistent. Clients who have been through trauma and are struggling with emotions, irrational thoughts/fears, etc., are the inspiration for developing the stages of validating feelings/emotions, combating irrational thoughts/fears, developing and implementing healthy coping skills and avoiding negative coping skills, regaining control and power, and being able to move forward. Too many who have experienced trauma turn to drugs (methamphetamine, cocaine, heroin) or alcohol to “numb” the pain and the memories. This paper is to assist in developing healthy techniques for processing and moving forward after a traumatic event.
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