第一篇：日本7、8世紀(jì)建筑
【摘要】日本建筑風(fēng)格的改變， 日本建筑的發(fā)展和風(fēng)格與政治和社會(huì)經(jīng)濟(jì)生活的變遷相關(guān)。
考生一回憶：
【回憶原文】7、8世紀(jì)之前，日本皇家喜歡move and replace因?yàn)橄矚g搬來搬去和木頭建材腐
爛什么的。后來繼承中國的方式，就有了主要宮殿和平常休閑的summer palace。 第一段，概述，講日本建筑風(fēng)格改變和政體及農(nóng)業(yè)改變是相關(guān)的。 第二段，介紹日本的舊建筑風(fēng)格是使用很多容易腐蝕的材料，日本人喜歡拆了蓋，蓋了拆，但是也算不上浪費(fèi)，因?yàn)榉孔有枰掭?，壞了的組件拿去扔掉，燒掉， 好的組件繼續(xù)用。第三段，就是說日本政治結(jié)合比較多，所以一大家子人住在palace里，這里有題，是縮寫題。 第四段，隨著日本發(fā)展，他們需要穩(wěn)定居所，然后發(fā)現(xiàn)china什么的有個(gè)首都， 有房子可以隨便住，這個(gè)好，他們也要這么干。
考生二回憶：
【回憶原文】日本建筑的改變。 7,8世紀(jì)之前日本建筑常用木頭等易腐蝕的材料，因此1-2年就需要換材料。換材料的過程常常是一個(gè)宗教儀式。由于日本傳統(tǒng)，日本統(tǒng)治者常常和他們配偶的家人住在一起(考點(diǎn))。到7-8世紀(jì)時(shí)候，由于統(tǒng)治者喜歡把材料和勞力掌握在自己手里，以及政府機(jī)關(guān)的擴(kuò)大，傳統(tǒng)的易腐蝕的建筑變得昂貴了。這時(shí)候中國先進(jìn)的建筑傳到日本，有幾點(diǎn)原因(考點(diǎn))。并且中國建筑體系和日本體系相融合，成為一個(gè)復(fù)合的體系(考點(diǎn))
【機(jī)經(jīng)解析】 考生主要回憶了日本早期建筑材料的使用和日本宮廷建筑因受中國建筑風(fēng)格的影響而進(jìn)行的發(fā)展和變遷，并體現(xiàn)了各階段日本建筑發(fā)展所帶來的社會(huì)益處。 【關(guān)鍵詞搜索】(含中英文)：日本古代/早期建筑，日本古代建筑材料，日本建筑受中國影響，日本宮廷建筑、日本建筑歷史。
材料一
Clustered around the main hall (the Daibutsuden) on a gently sloping hillside are a number of secondary halls: the Hokke-dō (Lotus Sutra Hall), the Kōfuku[3] and the storehouse, called the Shōsō-in. This last structure is of great importance as an art-historical cache, because in it are stored the utensils that were used in the temple's dedication ceremony in 752, as well as government documents and many secular objects owned by the Imperial family.[9]
【9】Itoh (1973)， P21. Fromhttp://en.wikipedia.org/wiki/Japanese_architecture#cite_note-Bussagli_168-12
材料二
The Heijo Capital and Palace
As we have already seen, Heijo was designed on a Chinese style grid plan(see fig.19). Basically a rectangle, the capital measured 4.7 km north to south, and 4.2 km east to west with additional sections extending beyond the rectangle to the northwest and east. At its height it is thought to have had a population of about two hundred thousand, including the immediate environs。
以下來源無法從網(wǎng)絡(luò)上復(fù)制黏貼：
Kazuo Nishi, Kazu Hozumi, What is Japanese Architecture? A survey of Traditional Japanese Architecture,
材料三
隋唐是中國古代繁榮、強(qiáng)盛的歷史時(shí)期之一，政治、經(jīng)濟(jì)、軍事、文藝、科技在當(dāng)時(shí)世界上都居前列，和四鄰的交往也很頻繁。對(duì)西面的中亞、南亞、中東諸國以商貿(mào)關(guān)系為主，使遠(yuǎn)方珍物的商品大量互相交流，以滿足雙方的獵奇愛好。在器物類型、裝飾紋樣乃至音樂、舞蹈諸方面，均對(duì)隋唐有某些影響，但在建筑方面，卻基本上沒有表現(xiàn)出來。對(duì)東面的朝鮮半島和日本則有著廣泛的政治、經(jīng)濟(jì)、文化交流，對(duì)其建筑發(fā)展有巨大而深遠(yuǎn)的影響。
Resource: 百度百科：http://baike.baidu.com/view/4234203.htm
第二篇：美國大堤的拆建
【摘要】大壩的修建和拆除對(duì)于三文魚等魚類的影響，以及經(jīng)濟(jì)效益和環(huán)境保護(hù)的利益權(quán)衡。
考生一回憶：
【回憶原文】首先說的是原來修建了很多大堤，現(xiàn)在不再建造新的，相反，要拆掉一些舊的，因?yàn)榄h(huán)境原因，恢復(fù)濕地，拯救三文魚什么的。然后講了幾個(gè)拆大堤的例子。
第二段是說大壩的， 以前認(rèn)為建大壩好，能發(fā)電各種好，現(xiàn)在風(fēng)向轉(zhuǎn)了，大家覺得建大壩對(duì)生態(tài)環(huán)境有影響。這里好像問了個(gè)問題，為啥政府不建大壩了，答案應(yīng)該是public反對(duì)。然后說 現(xiàn)在政府不建大項(xiàng)目了，舉了一種魚salmon(三文魚)做例子，大壩建了以后這種魚不能在自己的地方spawn(產(chǎn)卵)了， 所以散文魚瀕危了。
下面一段不太記得了，好像又舉了一種魚，說是這種魚即使把大壩remove了還是瀕危，因?yàn)檫@個(gè)魚產(chǎn)卵的地方現(xiàn)在有好多clay ，政府如果想讓魚活過來，還要花錢去清理這個(gè)好多clay的地方。
最后一段列了一堆問句， 是經(jīng)濟(jì)效益重要 還是環(huán)境重要? 是魚重要還是人重要，
考生二回憶：
【回憶原文】美國大壩建設(shè)。起初，美國大壩因?yàn)榭梢蕴峁┍阋说碾娏?，工作崗位和其他?jīng)濟(jì)因素(考點(diǎn))而廣泛建設(shè)。然而大壩破壞了原有的生態(tài)環(huán)境，上游被淹沒，salmon 回游產(chǎn)卵的路徑也被切斷。20世紀(jì)90年代后期，大壩建設(shè)由于不利于環(huán)境和生態(tài)的原因被迫停止。舊的大壩在renew審批時(shí)也會(huì)從環(huán)境的角度考慮。但是拆除大壩也有技術(shù)和經(jīng)濟(jì)的困難(考點(diǎn))。第一個(gè)被拆除的大壩是E.W大壩。由于E.W大壩的拆除，環(huán)保主義者們有了ambitious(詞匯題)的目標(biāo)。有人預(yù)測某大壩拆除后可以還山谷一個(gè)美麗的自然環(huán)境。
【關(guān)鍵詞搜索】(含中英文)：美國大壩的拆處、三文魚保護(hù)、三文魚產(chǎn)卵、美國大壩與三文魚
材料一
【以下材料與原文重合度高，幾乎與考生回憶一致】
Purposes and effects of dams
Many of the dams in the eastern US were built for water diversion, agriculture, factory watermills, and other purposes that are no longer useful. Because of the age of these dams, over time the risk for catastrophic failure increases. In addition, many of these dams block anadromous fish runs, such as Atlantic salmon and American shad, and prevent important sediments from reaching estuaries.
Many dams in the western US were built for agricultural water diversion in the arid country, with hydroelectricpower generation being a very significant side benefit. Among the largest of these water diversion projects is the Columbia Basin Project, which diverts water at the Grand Coulee Dam. The Bureau of Reclamation manages many of these water diversion projects.
Dams in the Pacific Northwest and California block passage for anadromous fish species such as Pacific Salmon and Steelhead. Fish ladders and other passage facilities have been largely ineffective in mitigating the negative effects on salmon populations. Bonneville Power Administration manages electricity on 11 dams on the Columbia River and 4 on the Snake River, which were built by the Army Corps of Engineers.
材料二
【考生所指的E.W.大壩，可能指的是美國Edward Dam，以下是解析材料】
1999 - Edwards Dam, Kennebec River, Maine – Built in 1837, the 24 ft (7.3 m) dam blocked access toAtlantic Salmon and American Shad. This was a landmark case in which a U.S. federal agency, the Federal Energy Regulatory Commission, required the decommissioning and removal of a dam against the operator's wishes.
維基百科http://en.wikipedia.org/wiki/Dam_removal
Edwards Dam Kennebec River,
Maine, USA
Removed July 1999 Sediment changes
(improved spawning
habitat); Improved
?sh passage
Dadswell 1996
University of Pennsylvania
材料三
Salmon Protection and Dam Removal
Salmon have a very important life cycle. They return to the same gravel bed
where they were hatched to lay their eggs and then die, providing the surrounding environment with nutrients that they would otherwise not have. A recent study documented 137 species that benefit from and utilize the ocean-origin nutrients that salmon deliver.[11] The creation of many dams along the Snake and Columbia Rivers have blocked Salmon access to some of the most pristine habitats available, preventing them for being able to spawn effectively as they would've done without the dams being in their way. Even though some dams have fish ladders to assist salmon in their journey up the river, many salmon often die on their return to their birthplace. If the dams were to be removed, and the region convert to utilizing alternative energy sources such as wind and wave power, this would allow for wild salmon to return to pristine habitats in which they could lay eggs that would more likely hatch and grow into substantial wild salmon and also provide nutrients to the already pristine habitat that will make it an even better salmon breeding area. In 2000, the Oregon Chapter of the American Fisheries Society—representing hundreds of fishery professionals—passed a resolution that "The four lower Snake River dams are a significant threat to the continued existence of remaining Snake River salmon and steelhead stocks; and if society wishes to restore these salmonids to sustainable, fishable levels, a significant portion of the lower Snake River must be returned to a free-flowing condition by breaching the four lower Snake River dams, and this action must happen soon".[12] It is vital to salmon conservation that the remaining wild salmon be able to spawn in safe, quality habitats so that the populations of salmon can rise again.
材料四
Dam Removal and Fish passage
Dams fragment the corridor of the river in several ways: they isolate populations and habitats, create physical and thermal obstructions for migrating and drifting stream organisms, and disrupt interactions between freshwater, terrestrial, and coastal systems (Winston and others 1991, Chisholm and Aadland 1994, Dynesius and Nilsson 1994, Stanford and others 1996). For instance, blocked migration of diadromous ?sh has been an issue for numerous dammed rivers. Many migratory ?sh are not euryhaline (i.e., they do not have mecha- 808 A. T. Bednareknisms to adapt their physiology to different salinities required for movement between fresh and saltwater) (McDowall 1992). The delays in migration time from encountering dams cause energy needed for migration or reproduction to be expended while ?sh are pooling above or below the dam. For example, the American shad reabsorbs its gonads when returning to the ocean if it is delayed, without releasing eggs or sperm (Dadswell 1996). In addition, predation often increases in pooling areas, where many ?sh accumulate waiting to pass the dam through ?sh ladders.
Dam removal may eliminate several problems associated with ?sh passage for migration or movement within the river channel. First, where a dam has no ?sh passage structures, removal eliminates mortality due to the inability to pass around the dam and allows organisms to inhabit previously impounded areas. For example, removal of small dams (in Denmark) has resulted in salmonids and other ?sh being able to reach optimum spawning grounds, enhancing their chances of survival (Iversen and others 1993). Second, where a dam has some form of ?sh passage, dam removal eliminates death or injuries to riverine organisms caused by passage mechanisms, such as turbine entrainment and ?sh ladder mortality (Travnicheck and others 1993, Dadswell 1996). Third, where a dam has some form of ?sh passage, dam removal eliminates delays such as waits at crowded upstream passage devices and downstream delays from swimming through the slow-moving reservoir. Since ?sh passage structures can not usually accommodate large numbers of ?sh at the same time, removal will speed ?sh movement and increase the odds of successful reproduction (Winter 1990, Drinkwater and Frank 1994, Wik 1995). Analyses of ?sh passage versus dam removal for the Enloe Dam on the Similameen River in Oregon, for example, suggested that added ?sh passage would not successfully accommodate the large number of migrating ?sh attempting to pass (Winter 1990).
Removal might also impact organisms that have never been observed using up- or downstream ?sh passages or that are too large or small for it (Dadswell 1996). For example, there are no records of smelt or Atlantic sturgeon utilizing ?sh passages on the North American East Coast (Dadswell 1996). Small ?sh, such as rainbow smelt, might not be able to maneuver through a passage designed to enhance salmon migration, a much larger and stronger swimmer (Dadswell 1996).
The success of efforts to restore river continuity also depends signi?cantly on the extent of the regulation throughout the river. If only one dam is removed on a river that has several, the continued presence of upstream or downstream obstructions limits the extent of the restoration process (Tyus and Winter 1992). One of the ?rst recorded dam removals, the Washington Water Power Dam on the Clearwater River in Idaho in 1963, has improved habitat quality and ?sh runs of Chinook salmon (Shuman 1995). However, the ?sh runs are not completely restored because of additional dams on the Snake and Columbia rivers through which the ?sh must maneuver (Shuman 1995).
ANGELA T. BEDNAREK
Department of Biology
University of Pennsylvania
Philadelphia, Pennsylvania 19104-6018, USA
The Patrick Center for Environmental Research
The Academy of Natural Sciences
1900 Benjamin Franklin Parkway
Philadelphia, Pennsylvania 19103
第三篇：月球上是否有水
【摘要】科學(xué)家研究月球上是否有水的各種方法和闡述月球上有水的好處。
考生回憶
【回憶原文】第一段說是科學(xué)家分析了月球某些成分，發(fā)現(xiàn)沒有有機(jī)物，而且月球上也沒有化石， 然后牽涉到月球上有沒有水的問題。后面各種發(fā)現(xiàn)，什么水可能在兩極啊，水可能在老火山口crater底部啊，還有探測到氫氣，這是水的成分，所以可能有水啊 什么的。然后說科學(xué)家為了證明有水，想把個(gè)快要過期的衛(wèi)星撞到月球上做實(shí)驗(yàn)，因?yàn)闀?huì)有蒸發(fā)出來的水，搞不好能探測到 什么的。然后說有水好呀，星際旅行帶水很貴(多少多少錢，有題)，要是能直接用，那就各種省錢啊什么的
【關(guān)鍵詞搜索】(含中英文)：月球上的水
材料一
Lunar water
is water that is present on the Moon. Liquid water cannot persist at the Moon's surface, and water vapour is quickly decomposed by sunlight and lost to outer space. However, scientists have since the 1960s conjectured that water ice could survive in cold, permanently shadowed craters at the Moon's poles.
Water, and the chemically related hydroxyl group ( • OH), can also exist in forms chemically bound to lunar minerals (rather than as free water), and evidence strongly suggests that this is indeed the case in low concentrations over much of the Moon's surface.[1] In fact, adsorbed water is calculated to exist at trace concentrations of 10 to 1000 parts per million.[2]
Inconclusive evidence of free water ice at the lunar poles was accumulated from a variety of observations suggesting the presence of bound hydrogen. In September 2009, India's Chandrayaan-1 detected water on the Moon [3][4] andhydroxyl absorption lines in reflected sunlight. In November 2009, NASA reported that its LCROSS space probe had detected a significant amount of hydroxyl group in the material thrown up from a south polar crater by an impactor;[5] this may be attributed to water-bearing materials[6] – what appears to be "near pure crystalline water-ice".[7] In March 2010, it was reported that the Mini-RF on board the India's Chandrayaan-1 had discovered more than 40 permanently darkened craters near the Moon's north pole which are hypothesized to contain an estimated 600 million metric tonnes(1.3 trillion pounds) of water-ice.[7][8]
Water may have been delivered to the Moon over geological timescales by the regular bombardment of water-bearingcomets, asteroids and meteoroids [9] or continuously produced in situ by the hydrogen ions (protons) of the solar wind impacting oxygen-bearing minerals.[10]
The search for the presence of lunar water has attracted considerable attention and motivated several recent lunar missions, largely because of water's usefulness in rendering long-term lunar habitation feasible.
Production
Lunar water has two potential origins: water-bearing comets (and other bodies) striking the Moon, and in situ production. It has been theorized that the latter may occur when hydrogen ions (protons) in the solar wind chemically combine with the oxygen atoms present in the lunar minerals (oxides,silicates etc.) to produce small amounts of water trapped in the minerals' crystal lattices or as hydroxyl groups, potential water precursors.[52](This mineral-bound water, or hydroxylated mineral surface, must not be confused with water ice.)
The hydroxyl surface groups (S–OH) formed by the reaction of protons (H+) with oxygen atoms accessible at oxide surface (S=O) could further be converted in water molecules (H2O) adsorbed onto the oxide mineral's surface. The mass balance of a chemical rearrangement supposed at the oxide surface could be schematically written as follows:
2 S-OH —> S=O + S + H2O
or,
2 S-OH —> S–O–S + H2O
where S represents the oxide surface.
The formation of one water molecule requires the presence of two adjacent hydroxyl groups, or a cascade of successive reactions of one oxygen atom with two protons. This could constitute a limiting factor and decreases the probability of water production if the proton density per surface unit is too low.
Trapping
Solar radiation would normally strip any free water or water ice from the lunar surface, splitting it into its constituent elements, hydrogen andoxygen, which then escape to space. However, because of the only very slight axial tilt of the Moon's spin axis to the ecliptic plane (1.5 °), some deep craters near the poles never receive any sunlight, and are permanently shadowed (see, for example, Shackleton crater, and Whipple crater). The temperature in these regions never rises above about 100 K (about −170 ° Celsius),[53] and any water that eventually ended up in these craters could remain frozen and stable for extremely long periods of time — perhaps billions of years, depending on the stability of the orientation of the Moon's axis.[18][24]
Transport
Although free water cannot persist in illuminated regions of the Moon, any such water produced there by the action of the solar wind on lunar minerals might, through a process of evaporation and condensation, migrate to permanently cold polar areas and accumulate there as ice, perhaps in addition to any ice brought by comet impacts.[16]
The hypothetical mechanism of water transport / trapping (if any) remains unknown: indeed lunar surfaces directly exposed to the solar wind where water production occurs are too hot to allow trapping by water condensation (and solar radiation also continuously decomposes water), while no (or much less) water production is expected in the cold areas not directly exposed to the sun. Given the expected short lifetime of water molecules in illuminated regions, a short transport distance would in principle increase the probability of trapping. In other words, water molecules produced close to a cold, dark polar crater should have the highest probability of surviving and being trapped.
To what extent, and at what spatial scale, direct proton exchange (protolysis) and proton surface diffusion directly occurring at the naked surface of oxyhydroxide minerals exposed to space vacuum (see surface diffusion and self-ionization of water) could also play a role in the mechanism of the water transfer towards the coldest point is presently unknown and remains a conjecture.
維基百科：http://en.wikipedia.org/wiki/Lunar_water
材料二
【完整版原文有待進(jìn)一步查找The full text of this paper to be found】
Water on the Moon
Department of Chemistry, University of California, San Diego, La Jolla, California.
*I presented these suggestions at the International Astronomical union meetings in Prague, August 1967.
THE possibility that water has existed on the Moon for varying lengths of time, both in liquid arid in solid form, and both beneath the surface and on the surface, has been widely discussed during the past 10 years1–7. The subject has been discussed repeatedly at scientific meetings and has been received mostly with great scepticism. Evidence supporting this view has recently become quite overwhelming and, in fact, no communication seems necessary to point out the evidence from the Orbiter 4 and 5 pictures8. Because many people are not aware of this evidence and suggest that the effects are caused by other liquids, that is, lava, dust-gas or possibly even vodka, a brief discussion of the evidence may be in order.
第四篇：pestcide殺蟲劑
【摘要】描述生物的、化學(xué)的和生物與化學(xué)相結(jié)合的三種殺蟲方式的優(yōu)劣
考生一回憶
講了三種殺蟲劑：
1. 化學(xué)的(不好，有resistance)
2. 生物的(也不好，有其他物種)
3. 綜合發(fā)揮法~~各種科技都用上~很好
考生二回憶
Pest control. (我憎恨美國的roach and bedbug )
Native pest 一般都好控制，有他的原始天敵。舶來的pest由于缺乏天敵很難控制。Pest control 有多種手段，一種是chemical control, 可以有效殺滅大部分害蟲。然而缺點(diǎn)有二。廣譜殺蟲會(huì)把益蟲也殺掉。而且pest會(huì)產(chǎn)生耐藥性。舉了一個(gè)蚊子的例子。第二種手段是biological control, 引入nonnative 的天敵，也可以控制pest 數(shù)量。例子是300EC中國果園就使用了這一方法(EC是神馬?)。缺點(diǎn)是非土著天敵由于新環(huán)境沒天敵破壞當(dāng)?shù)厣鷳B(tài)，舉例：澳大利亞。
最近有一種新手段，綜合了chemical和 biological control. 這個(gè)手段需要專業(yè)知識(shí)的人才。在pest爆發(fā)之前先用chemical control, 然后看情況決定用不用biological control
Types of biological pest control
There are three basic types of biological pest control strategies: importation (sometimes called classical biological control), augmentation and conservation.[1]
Importation
Importation (or "classical biological control") involves the introduction of a pest's natural enemies to a new locale where they do not occur naturally. This is usually done by government authorities. In many instances the complex of natural enemies associated with a pest may be inadequate, a situation that can occur when a pest is accidentally introduced into a new geographic area, without its associated natural enemies. These introduced pests are referred to as exotic pests and comprise about 40% of the insect pests in the United States.
The process of importation involves determining the origin of the introduced pest and then collecting appropriate natural enemies associated with the pest or closely related species. Selected natural enemies are then passed through a rigorous assessment, testing and quarantine process, to ensure that they will work and that no unwanted organisms (such as hyperparasitoids) are introduced. If these procedures are passed, the selected natural enemies are mass produced and then released. Follow-up studies are conducted to determine if the natural enemy becomes successfully established at the site of release, and to assess the long-term benefit of its presence.
To be most effective at controlling a pest, a biological control agent requires a colonizing ability which will allow it to keep pace with the spatial and temporal disruption of the habitat. Its control of the pest will also be greatest if it has temporal persistence, so that it can maintain its population even in the temporary absence of the target species, and if it is an opportunistic forager, enabling it to rapidly exploit a pest population.[2] However an agent with such attributes is likely to be non-host specific, which is not ideal when considering its overall ecological impact, as it may have unintended effects on non-target organisms.
There are many examples of successful importation programs, including:
Joseph Needham noted a Chinese text dating from 304AD, Records of the Plants and Trees of the Southern Regions, by Hsi Han, which describes mandarin oranges protected by biological pest control techniques that are still in use today.
材料二
Biological Vs. Chemical Pest Control
By Damien Campbell, eHow Contributor
There are multiple methods avaiable to control pests.
There are a number of chemical and biological options that control pests in various ways. The options available to landowners to manage pests and maintain healthy crops are diverse and both chemical and biological methods have their own advantages and disadvantages.
Chemical Control
• Chemical pesticides are substances that are manufactured in laboratories that, when applied to crops, reduce the vitality of pest populations while leaving crops unharmed. There are many chemicals available to help eradicate common pests in a number of ways. Chemical controls can kill pests that come in contact with the chemical (toxicants), eliminate the reproductive potential of pests (sterilants), disrupt their developmental potential (growth regulators) or influence their behavior (semiochemicals). Most of these chemical controls are fast acting and effective.
Biological Control
• Biological control methods employ the use of living organisms such as predators, parasites and pathogens to control the populations of pests on agricultural crops. Biological control agents can be bred and reared in large numbers and then released into infected crops to reduce the populations of pests (augmentation) or simple land conservation measures can be implemented on agricultural lands that maintain healthy populations of native predators (conservation). Many pests that cause damages to crops thrive because they are invasive and have no natural predators. Finding and importing predators of these invasive pests is essential for effective biological pest control.
Benefits
• Chemical controls are cheap and readily available. Chemical controls, especially toxicants, have been in use since the 1940's and have remained in popular use due to their fast acting and effective results in controlling pest populations. Many new chemicals have been developed in recent years that are even more efficient in controlling pests, maintaining the popularity of chemical control in agricultural practices. However, biological control has seen an increase in use in recent years due to its perennial and organic nature. Many biological control methods remain in effect year after year, limiting pests without any additional costs or synthetic additives to the natural environment.
Considerations
• While chemical controls are often effective they are usually seasonal and require reapplication with each growing season. Biological controls may take a longer period of time to see the desired results, but they only require the initial investment and introduction to control pests. Chemical controls also have additional environmental costs. Many chemical pesticides are persistent in the environment, damage organisms other than the pests they are meant to control (including humans) and are not permanently effective, as pest populations can build up a resistance to chemicals over time. Thus, while chemical controls may be more economical and effective in the short term, their use requires caution and consideration for future costs, both environmental and economic.
Integration
• While some landowners look only at seasonal profits and depend on chemical methods, others contemplate only the environmental sustainability of their practices and opt for biological methods. However, many landowners blend chemical and biological controls together in order to maximize profits while minimizing costs as well as reduce the environmental impact on their land. The use of multiple pest control methods is referred to as integrated pest management (IPM). Dense infestations often require the potency of chemical pest control but limited application, coupled with preventative biological control, is the most effective agricultural management practice.