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Understanding Ecological Succession

Ecological succession is the progressive change, in an ecosystem, of species composition over time. With the change in species composition comes a series of modifications in community structure and function. A classic example of succession involves the series of changes observed in an abandoned field in what is normally a forested area. Once the field is no longer grazed or mowed, the seeds of shrubs and trees will sprout and rapidly start growing. Before long, shrubs and tree saplings will be the dominant vegetation form. The tree species will then grow to the point of shading out the shrubs, eventually forming a complete canopy. The species composition in that young forest will continue to turn over until it is dominated by a stable, self-maintaining group of species called a climax community. Primary vs. Secondary Succession Ecological succession where there was no vegetation prior is called primary succession. We can observe primary succession on bulldozed sites, after an intense fire, or following a volcanic eruption, for example. The first plant species to show up have the ability to very quickly colonize and grow in these bare areas. Depending on the region, these pioneer species can be grasses, broadleaf plantain, Queen Anne’s lace, or trees like aspen, alder, or black locust. The pioneers set up the stage for the next phase of succession, improving soil chemistry and adding organic matter which provides nutrients, better soil structure, and greater water-holding capacity. Secondary succession occurs when a new set of organisms appears where there was an ecological set-back (for example a clear-cut logging operation) but where a cover of living plants was left behind. The abandoned agricultural field described above is a perfect example of secondary succession. Common plants during this stage are raspberries, asters, goldenrods, cherry trees, and paper birch. Climax Communities and Disturbance The last stage of succession is the climax community. In a forest, climax species are those that can grow in the shade of taller  trees – hence the name shade-tolerant species. The composition of climax communities varies geographically. In parts of the eastern United States, a climax forest will be made of sugar maples, eastern hemlock, and American beech. In Washington State’s Olympic National Park, the climax community may be dominated by western hemlock, Pacific silver fir, and western redcedar. A common misconception is that climax communities are permanent and frozen in time. In reality, the oldest trees eventually die and are replaced by other trees waiting under the canopy. This makes climax canopy part of a dynamic equilibrium, always changing but overall looking the same. Significant changes will occasionally be brought about by disturbances. Disturbances can be wind damage from a hurricane, a wildfire, an insect attack, or even logging. The type, size, and frequency of disturbances vary by region – some coastal, wet locations experience fires on average once every few thousand years, while eastern boreal forests may be subject to spruce budworm kills every few decades. These disturbances knock back the community into an earlier successional stage, restarting the process of ecological succession. The Value of Late Successional Habitat The dark shade and tall canopies of climax forests provide shelter for a number of specialized birds, mammals, and other organisms. The cerulean warbler, wood thrush, and red-cockaded woodpecker  are dwellers of old forests. The threatened spotted owl and Humboldt fisher both require large stands of late successional redwood and Douglas-fir forests. Many small flowering plants and ferns rely on the shady forest floor beneath old trees. The Value of Early Successional Habitat There is also considerable value in early successional habitat. These shrubland and young forests rely on recurring disturbances that set succession back. Unfortunately, in many places, these disturbances often turn forests into housing developments and other land uses that short-cut the ecological succession process. As a result, shrublands and young forests can become quite rare on the landscape. Many birds rely on early successional habitats, including the brown thrasher, golden-winged warbler, and prairie warbler. There are also mammals that need shrubby habitat, perhaps most notably the New England cottontail.

Vampire Academy Chapter 8 Free Essays

string(41) " the fox kept flashing through her mind\." EIGHT BURNING WITH ANGER, I FOUGHT harder and better that day than I ever had in any of my classes with the novices. So much so that I finally won my first hand-to-hand pairing, annihilating Shane Reyes. We’d always gotten along, and he took it good-naturedly, applauding my performance, as did a few others. We will write a custom essay sample on Vampire Academy Chapter 8 or any similar topic only for you Order Now â€Å"The comeback’s starting,† observed Mason after class. â€Å"So it would seem.† He gently touched my arm. â€Å"How’s Lissa?† It didn’t surprise me that he knew. Gossip spread so fast around here sometimes, it felt like everyone had a psychic bond. â€Å"Okay. Coping.† I didn’t elaborate on how I knew that. Our bond was a secret from the student body. â€Å"Mase, you claim to know about Mia. You think she might have done that?† â€Å"Whoa, hey, I’m not an expert on her or anything. But honestly? No. Mia won’t even do dissections in biology. I can’t picture her actually catching a fox, let alone, um, killing it.† â€Å"Any friends who might do it for her?† He shook his head. â€Å"Not really. They’re not really the types to get their hands dirty either. But who knows?† Lissa was still shaken when I met her for lunch later, her mood made worse when Natalie and her crew wouldn’t shut up about the fox. Apparently Natalie had overcome her disgust enough to enjoy the attention the spectacle had brought her. Maybe she wasn’t as content with her fringe status as I’d always believed. â€Å"And it was just there,† she explained, waving her hands for emphasis. â€Å"Right in the middle of the bed. There was blood everywhere.† Lissa looked as green as the sweater she wore, and I pulled her away before I even finished my food and immediately launched into a string of obscenities about Natalie’s social skills. â€Å"She’s nice,† Lissa said automatically. â€Å"You were just telling me the other day how much you liked her.† â€Å"I do like her, but she’s just incompetent about certain things.† We stood outside our animal behavior class, and I noticed people giving us curious looks and whispering as they passed. I sighed. â€Å"How are you doing with all this?† A half-smile crossed her face. â€Å"Can’t you already feel it?† â€Å"Yeah, but I want to hear it from you.† â€Å"I don’t know. I’ll be okay. I wish everyone wouldn’t keep staring at me like I’m some kind of freak.† My anger exploded again. The fox was bad. People upsetting her made it worse, but at least I could do something about them. â€Å"Who’s bothering you?† â€Å"Rose, you can’t beat up everyone we have a problem with.† â€Å"Mia?† I guessed. â€Å"And others,† she said evasively. â€Å"Look, it doesn’t matter. What I want to know is how this could have? ­that is, I can’t stop thinking about that time – â€Å" â€Å"Don’t,† I warned. â€Å"Why do you keep pretending that didn’t happen? You of all people. You made fun of Natalie for going on and on, but it’s not like you’ve got a good grip on your control switch. You’ll normally talk about anything.† â€Å"But not that. We need to forget about it. It was a long time ago. We don’t even really know what happened.† She stared at me with those big green eyes, calculating her next argument. â€Å"Hey, Rose.† Our conversation dropped as Jesse strolled up to us. I turned on my best smile. â€Å"Hey.† He nodded cordially to Lissa. â€Å"So hey, I’m going to be in your dorm tonight for a study group. You think? ­maybe? ­Ã¢â‚¬  Momentarily forgetting Lissa, I focused my full attention on Jesse. Suddenly, I so needed to do something wild and bad. Too much had happened today. â€Å"Sure.† He told me when he’d be there, and I told him I’d meet him in one of the common areas with â€Å"further instructions.† Lissa stared at me when he left. â€Å"You’re under house arrest. They won’t let you hang out and talk to him.† â€Å"I don’t really want to ? ®talk’ to him. We’ll slip away.† She groaned. â€Å"I just don’t know about you sometimes.† â€Å"That’s because you’re the cautious one, and I’m the reckless one.† Once animal behavior started, I pondered the likelihood of Mia being responsible. From the smug look on her psycho-angel face, she certainly seemed to be enjoying the sensation caused by the bloody fox. But that didn’t mean she was the culprit, and after observing her over the last couple of weeks, I knew she’d enjoy anything that upset Lissa and me. She didn’t need to be the one who had done it. â€Å"Wolves, like many other species, differentiate their packs into alpha males and alpha females whom the others defer to. Alphas are almost always the strongest physically, though many times, confrontations turn out to be more a matter of willpower and personality. When an alpha is challenged and replaced, that wolf may find himself ostracized from the group or even attacked.† I looked up from my daydreams and focused on Ms. Meissner. â€Å"Most challenges are likely to occur during mating season,† she continued. This, naturally, brought snickers from the class. â€Å"In most packs, the alpha pair are the only ones who mate. If the alpha male is an older, seasoned wolf, a younger competitor may think he has a shot. Whether that is true works on a case-by-case basis. The young often don’t realize how seriously outclassed they are by the more experienced.† The old-and-young-wolf thing notwithstanding, I thought the rest was pretty relevant. Certainly in the Academy’s social structure, I decided bitterly, there seemed to be a lot of alphas and challenges. Mia raised her hand. â€Å"What about foxes? Do they have alphas too?† There was a collective intake of breath from the class, followed by a few nervous giggles. No one could believe Mia had gone there. Ms. Meissner flushed with what I suspected was anger. â€Å"We’re discussing wolves today, Miss Rinaldi.† Mia didn’t seem to mind the subtle chastising, and when the class paired off to work on an assignment, she spent more time looking over at us and giggling. Through the bond, I could feel Lissa growing more and more upset as images of the fox kept flashing through her mind. You read "Vampire Academy Chapter 8" in category "Essay examples" â€Å"Don’t worry,† I told her. â€Å"I’ve got a way – â€Å" â€Å"Hey, Lissa,† someone interrupted. We both looked up as Ralf Sarcozy stopped by our desks. He wore his trademark stupid grin, and I had a feeling he’d come over here on a dare from his friends. â€Å"So, admit it,† he said. â€Å"You killed the fox. You’re trying to convince Kirova you’re crazy so that you can get out of here again.† â€Å"Screw you,† I told him in a low voice. â€Å"Are you offering?† â€Å"From what I’ve heard, there isn’t much to screw,† I shot back. â€Å"Wow,† he said mockingly. â€Å"You have changed. Last I remembered, you weren’t too picky about who you got naked with.† â€Å"And the last I remember, the only people you ever saw naked were on the Internet.† He cocked his head in an overly dramatic fashion. â€Å"Hey, I just got it: it was you, wasn’t it?† He looked at Lissa, the back at me. â€Å"She got you to kill the fox, didn’t she? Some weird kind of lesbian voo-ahhh!† Ralf burst into flames. I jumped up and pushed Lissa out of the way – not easy to do, since we were sitting at our desks. We both ended up on the floor as screams – Ralf’s in particular-filled the classroom and Ms. Meissner sprinted for the fire extinguisher. And then, just like that, the flames disappeared. Ralf was still screaming and patting himself down, but he didn’t have a single singe mark on him. The only indication of what had happened was the lingering smell of smoke in the air. For several seconds, the entire classroom froze. Then, slowly, everyone put the pieces together. Moroi magical specializations were well known, and after scanning the room, I deduced three fire users: Ralf, his friend Jacob, and – Christian Ozera. Since neither Jacob nor Ralf would have set Ralf on fire, it sort of made the culprit obvious. The fact that Christian was laughing hysterically sort of gave it away too. Ms. Meissner changed from red to deep purple. â€Å"Mr. Ozera!† she screamed. â€Å"How dare you – do you have any idea – report to Headmistress Kirova’s office now!† Christian, completely unfazed, stood up and slung his backpack over one shoulder. That smirk stayed on his face. â€Å"Sure thing, Ms. Meissner.† He went out of his way to walk past Ralf, who quickly backed away as he passed. The rest of the class stared, open-mouthed. After that, Ms. Meissner attempted to return the class to normal, but it was a lost cause. No one could stop talking about what had happened. It was shocking on a few different levels. First, no one had ever seen that kind of spell: a massive fire that didn’t actually burn anything. Second, Christian had used it offensively. He had attacked another person. Moroi never did that. They believed magic was meant to take care of the earth, to help people live better lives. It was never, ever used as a weapon. Magic instructors never taught those kinds of spells; I don’t think they even knew any. Finally, craziest of all, Christian had done it. Christian, whom no one ever noticed or gave a damn about. Well, they’d noticed him now. It appeared someone still knew offensive spells after all, and as much as I had enjoyed the look of terror on Ralf’s face, it suddenly occurred to me that Christian might really and truly be a psycho. â€Å"Liss,† I said as we walked out of class, â€Å"please tell me you haven’t hung out with him again.† The guilt that flickered through the bond told me more than any explanation could. â€Å"Liss!† I grabbed her arm. â€Å"Not that much,† she said uneasily. â€Å"He’s really okay – â€Å" â€Å"Okay? Okay?† People in the hall stared at us. I realized I was practically shouting. â€Å"He’s out of his mind. He set Ralf on fire. I thought we decided you weren’t going to see him anymore.† â€Å"You decided, Rose. Not me.† There was an edge in her voice I hadn’t heard in a while. â€Å"What’s going on here? Are you guys? ­you know ­Ã¢â‚¬  â€Å"No!† she insisted. â€Å"I told you that already. God.† She shot me a look of disgust. â€Å"Not everyone thinks – and acts – like you.† I flinched at the words. Then we noticed that Mia was passing by. She hadn’t heard the conversation but had caught the tone. A snide smile spread over her face. â€Å"Trouble in paradise?† â€Å"Go find your pacifier, and shut the hell up,† I told her, not waiting to hear her response. Her mouth dropped open, then tightened into a scowl. Lissa and I walked on in silence, and then Lissa burst out laughing. Like that, our fight diffused. â€Å"Rose? ­Ã¢â‚¬  Her tone was softer now. â€Å"Lissa, he’s dangerous. I don’t like him. Please be careful.† She touched my arm. â€Å"I am. I’m the cautious one, remember? You’re the reckless one.† I hoped that was still true. But later, after school, I had my doubts. I was in my room doing homework when I felt a trickle of what could only be called sneakiness coming from Lissa. Losing track of my work, I stared off into space, trying to get a more detailed understanding of what was happening to her. If ever there was a time for me to slip into her mind, it was now, but I didn’t know how to control that. Frowning, I tried to think what normally made that connection occur. Usually she was experiencing some strong emotion, an emotion so powerful it tried to blast into my mind. I had to work hard to fight against that; I always sort of kept a mental wall up. Focusing on her now, I tried to remove the wall. I steadied my breathing and cleared my mind. My thoughts didn’t matter, only hers did. I needed to open myself to her and let us connect. I’d never done anything like this before; I didn’t have the patience for meditation. My need was so strong, however, that I forced myself into an intense, focused relaxation. I needed to know what was going on with her, and after a few more moments, my effort paid off. I was in. How to cite Vampire Academy Chapter 8, Essay examples

Nikki Essay Example For Students

Nikki Essay GiovanniNikki (Yolande Cornelia) Giovanni has made an enormous impact on AfricanAmerican literature. She uses her own experiences to write wonderful poetry. Inthe poem Nikki-Rosa, Nikki Giovanni writes the opposite about hergrowing up in her family. When I first read this poem, I pictured apoverty-stricken family living in a small apartment, much like the Youngerfamily in A Raisin in the Sun. Evidently, the family is poor because they haveno inside toilet and take baths in one of those/ big tubs that folk inchicago barbecue in (10-11). The family is not as concerned about povertyas they are for their love for one another, And though youre poor itisnt poverty that concerns you and though they fought a lot it isnt yourfathers drinking that makes any difference but only that everybody is togetherand you and your sister have happy birthdays and very good Christmasses(20-26) The poem reveals a good family does have its problems. I got the feelingthe children in the poem loved living where they lived although their parentswerent the richest, or they didnt live in the nicest house. The childrenrealized that there was more to life than having a pleasant house and delightfulthings. The children in the poem realize that family life is more important thanmaterial objects. The poem Nikki-Rosa was written based on the lifeof Nikki Giovanni. Nikki Giovannis childhood was very much different that theone described in the poem. Giovanni was raised in a middle class family,although she did learn of poverty from her parents who happened to be socialworkers (Wiedemann 1500). Her childhood could be described as very happy (Great178). Giovannis world in her poetry is an extension of her real life. Often,she sees herself existing among tensions. Biographers who write about NikkiGiovanni always comment on the poverty of the family, her parents fighting, andnote her fathers alcoholism, but almost never comment on the closeness of herfamily or the richness of a strong, supportive family (Wiedemann 1499). tisnt your fathers drinking that makes any difference/ but only that everybodyis together (23-24). This line in the poem sums up very well the feelingof family in the home of Nikki Giovanni during her childhood. The poem is notautobiographical of Giovannis life, but it does parallel the development of herradical conscious (Wiedemann 1500). Nikki-Rosa is a typical exampleof a poem by Nikki Giovanni. She writes about what she knows and what she hasexperienced. The poetry of Giovanni is related to issues African-Americans faceon a daily basis. According to Don L. Lee, she knows the need for Blackawareness, unity, and, solidarity; she has lived through it, and knows a changecan be affected. (182) Nikki Giovannis poetry contains no punctuation,symbolizing a continuous thought (Wiedemann 1499). Typically there is no form inher poetry. A wide audience has read her poems because of the simplicity of thelanguage used and the imagery of everyday life (Wiedemann 1499). Giova nni rarelyuses difficult symbols and avoids the usage of complex vocabulary to convey themeaning of her poetry, especially Nikki-Rosa (Wiedemann 1500). Barbara Wiedemann comments that Nikki-Rosa hints at the division ofwhites and blacks (1500). In Wiedemanns interview with Giovanni, she statesthat whites cannot understand the black experience, and because of the powerstructure in America, whites should be held accountable for the povertyexperienced by the black population. Giovanni believes differences in educationcause poverty, a lack of social services, and discrimination. (1500) This poem,written the day after Martin Luther King, Jr.s death is supposed to represent ayoung person growing up in an impoverished family who later becomes a blackactivist. The Nikki in the poem is not Nikki Giovanni. However, Rosa is RosaParks, the same Rosa who, in 1955, refused to give up her bus seat to a whitewoman. Giovanni writes about these kinds of things because she herself hasattended antiwar demonstrations, the Civil Rights Movement, and various riotsthroughout the nation. These and other events such as the assassinations ofMartin Luther King , Jr., Malcolm X, and Robert Kennedy helped to radicalizeNikki Giovanni (Wiedemann 1500). Nikki Giovanni uses her knowledge of subjectsrelated blacks to write her poetry. Within her poetry, she emphasizes theimportance of family and love in the family to create a success. In her ownfamily, she had two loving parents and siblings. She used her knowledge andexperience to write the poem Nikki-Rosa. Giovanni is a poet whowrote about what she knew the most about, black culture and the importance offamily. .ue5aadc486a58d0a33f3699da11edd18c , .ue5aadc486a58d0a33f3699da11edd18c .postImageUrl , .ue5aadc486a58d0a33f3699da11edd18c .centered-text-area { min-height: 80px; position: relative; } .ue5aadc486a58d0a33f3699da11edd18c , .ue5aadc486a58d0a33f3699da11edd18c:hover , .ue5aadc486a58d0a33f3699da11edd18c:visited , .ue5aadc486a58d0a33f3699da11edd18c:active { border:0!important; } .ue5aadc486a58d0a33f3699da11edd18c .clearfix:after { content: ""; display: table; clear: both; } .ue5aadc486a58d0a33f3699da11edd18c { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .ue5aadc486a58d0a33f3699da11edd18c:active , .ue5aadc486a58d0a33f3699da11edd18c:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .ue5aadc486a58d0a33f3699da11edd18c .centered-text-area { width: 100%; position: relative ; } .ue5aadc486a58d0a33f3699da11edd18c .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .ue5aadc486a58d0a33f3699da11edd18c .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .ue5aadc486a58d0a33f3699da11edd18c .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .ue5aadc486a58d0a33f3699da11edd18c:hover .ctaButton { background-color: #34495E!important; } .ue5aadc486a58d0a33f3699da11edd18c .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .ue5aadc486a58d0a33f3699da11edd18c .ue5aadc486a58d0a33f3699da11edd18c-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .ue5aadc486a58d0a33f3699da11edd18c:after { content: ""; display: block; clear: both; } READ: Drug addiction EssayBibliographyGiovanni, Nikki. Gemini. Indianapolis: The Bobbs-Merrill Company, Inc. 1971. . Racism 101. New York: William Morrow and Company, Inc., 1994. Lee, Don L. Nikki Giovanni. Contemporary Literary Criticism Volume 64. CarolynRiley, ed. Detroit: Gale Research Co. Great Women Writers. Frank N. Magill, ed. New York: Henry Colt Company. 1994 Wiedemann, Barbara. NikkiGiovanni. Masterplots II: Poetry Series Volume 4. Frank N. Magill, ed. Englewood Cliffs, New Jersey: Salem Press. 1992.