Misplaced Pages

#124875

104-549: The district has been inhabited since the Stone Age (50-45,000 BC). Two ancient settlements were founded around 1300 BC; archaeologists have found items belonging to the Bronze Age (15th-13th centuries BC). According to estimates of specialists, another village was established here around 300-400 BC. That has been confirmed by the remains of houses burned and the fragments of clay pots. Archaeological monuments recorded

208-760: A conference in anthropology held by the Wenner-Gren Foundation, at Burg Wartenstein Castle, which it then owned in Austria, attended by the same scholars that attended the Pan African Congress, including Louis Leakey and Mary Leakey , who was delivering a pilot presentation of her typological analysis of Early Stone Age tools, to be included in her 1971 contribution to Olduvai Gorge , "Excavations in Beds I and II, 1960–1963." However, although

312-493: A continuous fall in percentage the last three elections During the last three elections AEI had an increase of 43.2% Cahul district has a hospital with 500 beds , a center of family doctors , 28 family doctors' offices, 9 health centers and 12 medical points. 45°50′N 28°20′E  /  45.833°N 28.333°E  / 45.833; 28.333 Stone Age Paleolithic Epipalaeolithic Mesolithic Neolithic The Stone Age

416-446: A decrease below the minimum leading to direct danger for amphibian life), increased pollution of surface water , the drying out of wetlands , more and larger wildfires , higher deflation intensity, loss of biodiversity , worse health of trees and the appearance of pests and dendroid diseases. Drought-induced mortality of trees lacks in most climate models in their representation of forests as land carbon sink . Economic losses as

520-491: A diverse climate, ranging from hot, dry regions to cooler, wetter highland regions. The region has considerable variability in seasonal rainfall and a very complex topography. In the northern parts of the region within the Nile basin (Ethiopia, Sudan), the rainfall is characterized by an unimodal cycle with a wet season from July to September. The rest of the region has a bimodal annual cycle, featuring long rains from March to May and

624-434: A factor which increases the gap between developed and developing countries . Effects vary according to vulnerability. For example, subsistence farmers are more likely to migrate during drought because they do not have alternative food-sources. Areas with populations that depend on water sources as a major food-source are more vulnerable to famine. Further examples of social and health consequences include: Wind erosion

728-420: A hammerstone to obtain large and small pieces with one or more sharp edges. The original stone is called a core; the resultant pieces, flakes. Typically, but not necessarily, small pieces are detached from a larger piece, in which case the larger piece may be called the core and the smaller pieces the flakes . The prevalent usage, however, is to call all the results flakes, which can be confusing. A split in half

832-498: A high level of reflected sunlight and above average prevalence of high pressure systems , winds carrying continental, rather than oceanic air masses, and ridges of high pressure areas aloft can prevent or restrict the developing of thunderstorm activity or rainfall over one certain region. Once a region is within drought, feedback mechanisms such as local arid air, hot conditions which can promote warm core ridging, and minimal evapotranspiration can worsen drought conditions. Within

936-434: A longer duration. Precipitation can be divided into three categories, based on whether it falls as liquid water, liquid water that freezes on contact with the surface, or ice. Droughts occur mainly in areas where normal levels of rainfall are, in themselves, low. If these factors do not support precipitation volumes sufficiently to reach the surface over a sufficient time, the result is a drought. Drought can be triggered by

1040-465: A multi-agency partnership, drought is generally defined as "a deficiency of precipitation over an extended period of time (usually a season or more), resulting in a water shortage". The National Weather Service office of the NOAA defines drought as "a deficiency of moisture that results in adverse impacts on people, animals, or vegetation over a sizeable area". Drought is a complex phenomenon − relating to

1144-782: A new Lower Paleolithic tool, the hand axe, appeared. The earliest European hand axes are assigned to the Abbevillian industry , which developed in northern France in the valley of the Somme River ; a later, more refined hand-axe tradition is seen in the Acheulian industry , evidence of which has been found in Europe, Africa, the Middle East, and Asia. Some of the earliest known hand axes were found at Olduvai Gorge (Tanzania) in association with remains of H. erectus . Alongside

SECTION 10

#1732797519125

1248-606: A result of droughts include lower agricultural, forests, game and fishing output, higher food-production costs, lower energy-production levels in hydro plants, losses caused by depleted water tourism and transport revenue, problems with water supply for the energy sector and for technological processes in metallurgy, mining, the chemical, paper, wood, foodstuff industries etc., disruption of water supplies for municipal economies. Further examples of common environmental and economic consequences of drought include: Droughts can cause land degradation and loss of soil moisture, resulting in

1352-549: A result. This means even regions where overall rainfall is expected to remain relatively stable will experience these impacts. These regions include central and northern Europe. Without climate change mitigation, around one third of land areas are likely to experience moderate or more severe drought by 2100. Due to global warming droughts are more frequent and intense than in the past. Human activity can directly trigger exacerbating factors such as over-farming, excessive irrigation , deforestation , and erosion adversely impact

1456-606: A separate Copper Age or Bronze Age. Moreover, the technologies included in those 'stages', as Goodwin called them, were not exactly the same. Since then, the original relative terms have become identified with the technologies of the Paleolithic and Mesolithic, so that they are no longer relative. Moreover, there has been a tendency to drop the comparative degree in favor of the positive: resulting in two sets of Early, Middle and Late Stone Ages of quite different content and chronologies. By voluntary agreement, archaeologists respect

1560-514: A settlement arising from employment of Dacia in the Roman Empire and devastated by the Huns in 376. The presence of nomads in these places is attested by the four burial mounds . Localities with the earliest documented attestation are Crihana Veche , Manta , Valeni , Slobozia Mare , and Larga Veche ; they were documented for the first time in 1425–1447. In the 16th and 17th centuries,

1664-663: A significant role in drought. ENSO comprises two patterns of temperature anomalies in the central Pacific Ocean , known as La Niña and El Niño . La Niña events are generally associated with drier and hotter conditions and further exacerbation of drought in California and the Southwestern United States , and to some extent the U.S. Southeast . Meteorological scientists have observed that La Niñas have become more frequent over time. Conversely, during El Niño events, drier and hotter weather occurs in parts of

1768-570: A single dataset can be limiting, as it may not capture the full spectrum of drought characteristics and impacts. Careful monitoring of moisture levels can also help predict increased risk for wildfires. Mechanisms of producing precipitation include convective , stratiform , and orographic rainfall. Convective processes involve strong vertical motions that can cause the overturning of the atmosphere in that location within an hour and cause heavy precipitation, while stratiform processes involve weaker upward motions and less intense precipitation over

1872-786: A time known as the Copper Age (or more technically the Chalcolithic or Eneolithic, both meaning 'copper–stone'). The Chalcolithic by convention is the initial period of the Bronze Age. The Bronze Age was followed by the Iron Age . The transition out of the Stone Age occurred between 6000 and 2500  BC for much of humanity living in North Africa and Eurasia . The first evidence of human metallurgy dates to between

1976-666: A water supply crisis across much of the country. As a result, many desalination plants were built for the first time ( see list ). By far the largest part of Australia is desert or semi-arid lands commonly known as the outback . A 2005 study by Australian and American researchers investigated the desertification of the interior, and suggested that one explanation was related to human settlers who arrived about 50,000 years ago. Regular burning by these settlers could have prevented monsoons from reaching interior Australia. In June 2008 it became known that an expert panel had warned of long term, maybe irreversible, severe ecological damage for

2080-565: A wide range of techniques derived from multiple fields. The work of archaeologists in determining the paleocontext and relative sequence of the layers is supplemented by the efforts of geologic specialists in identifying layers of rock developed or deposited over geologic time; of paleontological specialists in identifying bones and animals; of palynologists in discovering and identifying pollen, spores and plant species; of physicists and chemists in laboratories determining ages of materials by carbon-14 , potassium-argon and other methods. The study of

2184-496: A widespread blanket deposit that covers areas of hundreds of square kilometers and tens of meters thick. Loess often stands in either steep or vertical faces. Loess tends to develop into highly rich soils. Under appropriate climatic conditions, areas with loess are among the most agriculturally productive in the world. Loess deposits are geologically unstable by nature, and will erode very readily. Therefore, windbreaks (such as big trees and bushes) are often planted by farmers to reduce

SECTION 20

#1732797519125

2288-452: Is 129. The total number of students in schools is 23,059, in colleges is 1,450, in vocational schools is 776, in universities is 2,547, and in sports schools is 585. There are four museums , 85 bands, 25 with the title of model, 47 houses of culture , and 48 libraries . Cahul district has mainly right-wing parties . In Moldova, Cahul is represented by the AEI . The PCRM has had

2392-426: Is a similar concept to water scarcity . The different categories of droughts have different causes but similar effects: Several indices have been defined to quantify and monitor drought at different spatial and temporal scales. A key property of drought indices is their spatial comparability, and they must be statistically robust. Drought indices include: High-resolution drought information helps to better assess

2496-453: Is also negatively effected by drought stress, the reduction in crop yield results from a decrease in photosynthetic rate, changes in leaf development, and altered allocation of resources all due to drought stress. Crop plants exposed to drought stress suffer from reductions in leaf water potential and transpiration rate. Water-use efficiency increases in crops such as wheat while decreasing in others, such as potatoes. Plants need water for

2600-535: Is associated with the remains of Neanderthal man . The earliest documented stone tools have been found in eastern Africa, manufacturers unknown, at the 3.3 million-year-old site of Lomekwi 3 in Kenya. Better known are the later tools belonging to an industry known as Oldowan , after the type site of Olduvai Gorge in Tanzania. The tools were formed by knocking pieces off a river pebble, or stones like it, with

2704-699: Is based on the Prut River and the Danube River , which forms meadows , ponds , natural lakes . The two biggest natural lakes in Moldova are in this region, Manta (21 km2) and Beleu (11 km2). An area of 1,200 meters is accessible from the Danube to the Black Sea , and basins of Central and Eastern Europe . As of 1 January 2012, the district population was 124,900, of which 31.9% was urban and 68.1%

2808-542: Is called bipolar flaking. Consequently, the method is often called "core-and-flake". More recently, the tradition has been called "small flake" since the flakes were small compared to subsequent Acheulean tools . The essence of the Oldowan is the making and often immediate use of small flakes. Another naming scheme is "Pebble Core Technology (PBC)": Pebble cores are ... artifacts that have been shaped by varying amounts of hard-hammer percussion. Various refinements in

2912-477: Is in the nature of this boundary. If there is no distinct boundary, then the population of A suddenly stopped using the customs characteristic of A and suddenly started using those of B, an unlikely scenario in the process of evolution . More realistically, a distinct border period, the A/B transition, existed, in which the customs of A were gradually dropped and those of B acquired. If transitions do not exist, then there

3016-477: Is insufficient rainfall to support vegetation. Drought is one of the most complex and major natural hazards , and it has devastating impacts on the environment, economy, water resources, agriculture, and society worldwide. One can divide the impacts of droughts and water shortages into three groups: environmental, economic and social (including health). Environmental effects of droughts include: lower surface and subterranean water-levels, lower flow-levels (with

3120-542: Is located in the southern part of the Republic of Moldova . The district is located in the extreme southern point of Moldova in Giurgiulești village . Cantemir District is in the north, Gagauzia in the northeast, Taraclia District in the east, the border of Ukraine in the south and Romania in the west. The land is made up of hilly plains with variations in altitude from 230 to 240 m (750 to 790 ft) in

3224-494: Is much more severe in arid areas and during times of drought. For example, in the Great Plains , it is estimated that soil loss due to wind erosion can be as much as 6100 times greater in drought years than in wet years. Loess is a homogeneous, typically nonstratified, porous, friable , slightly coherent, often calcareous, fine-grained, silty , pale yellow or buff, windblown ( Aeolian ) sediment . It generally occurs as

Cahul District - Misplaced Pages Continue

3328-621: Is no proof of any continuity between A and B. The Stone Age of Europe is characteristically in deficit of known transitions. The 19th and early 20th-century innovators of the modern three-age system recognized the problem of the initial transition, the "gap" between the Paleolithic and the Neolithic. Louis Leakey provided something of an answer by proving that man evolved in Africa. The Stone Age must have begun there to be carried repeatedly to Europe by migrant populations. The different phases of

3432-571: Is now considered to be a facies of Acheulean , while Sangoan is a facies of Lupemban . Magosian is "an artificial mix of two different periods". Once seriously questioned, the intermediates did not wait for the next Pan African Congress two years hence, but were officially rejected in 1965 (again on an advisory basis) by Burg Wartenstein Conference #29, Systematic Investigation of the African Later Tertiary and Quaternary ,

3536-586: Is possible to speak of a general 'Stone Age' period for the whole of humanity, some groups never developed metal- smelting technology, and so remained in the so-called 'Stone Age' until they encountered technologically developed cultures. The term was innovated to describe the archaeological cultures of Europe. It may not always be the best in relation to regions such as some parts of the Indies and Oceania, where farmers or hunter-gatherers used stone for tools until European colonisation began. Archaeologists of

3640-421: Is present in two garment factories (SA Tricon and Laboratorio Tessala Mol SRL). Building materials are present in plant and plant ceramsite concrete. Agriculture is the main branch of the district. Of the total 154,600 ha, 64% is agricultural land. The largest share of arable land is: 81%, perennial plantations . 18% incumbent, and 1% vegetable plantations. The total number of educational institutions

3744-410: Is related to low runoff, streamflow, and reservoir and groundwater storage. An agricultural or ecological drought is causing plant stress from a combination of evaporation and low soil moisture . Some organizations add another category: socioeconomic drought occurs when the demand for an economic good exceeds supply as a result of a weather-related shortfall in water supply. The socioeconomic drought

3848-493: Is the heterogeneous distribution of hydrologic extremes in space and time. For instance, El Niño can cause droughts in one part of the region and floods in the other. This is also a common situation within a country, e.g., in Ethiopia. The recent years with consecutive droughts followed by floods are a testament to the need to better forecast these kinds of events and their impacts. Approximately 2.4 billion people live in

3952-648: The 6th and 5th millennia  BC in the archaeological sites of the Vinča culture , including Majdanpek , Jarmovac , Pločnik , Rudna Glava in modern-day Serbia. Ötzi the Iceman , a mummy from about 3300 BC, carried with him a copper axe and a flint knife. In some regions, such as Sub-Saharan Africa , the Stone Age was followed directly by the Iron Age. The Middle East and Southeast Asian regions progressed past Stone Age technology around 6000 BC. Europe, and

4056-1084: The Amazon River Basin, Colombia , and Central America . Winters during the El Niño are warmer and drier than average conditions in the Northwest, northern Midwest, and northern Mideast United States, so those regions experience reduced snowfalls. Conditions are also drier than normal from December to February in south-central Africa, mainly in Zambia , Zimbabwe , Mozambique , and Botswana . Direct effects of El Niño resulting in drier conditions occur in parts of Southeast Asia and Northern Australia , increasing bush fires , worsening haze , and decreasing air quality dramatically. Drier-than-normal conditions are also in general observed in Queensland , inland Victoria , inland New South Wales , and eastern Tasmania from June to August. As warm water spreads from

4160-527: The Amazon basin , Australia , the Sahel region and India . For example, in 2005, parts of the Amazon basin experienced the worst drought in 100 years. Australia could experience more severe droughts and they could become more frequent in the future, a government-commissioned report said on July 6, 2008. The long Australian Millennial drought broke in 2010. The 2020–2022 Horn of Africa drought has surpassed

4264-608: The Fauresmith and Sangoan technologies, and the Second Intermediate Period between Middle and Later, to encompass the Magosian technology and others. The chronologic basis for the definition was entirely relative. With the arrival of scientific means of finding an absolute chronology, the two intermediates turned out to be will-of-the-wisps . They were in fact Middle and Lower Paleolithic . Fauresmith

Cahul District - Misplaced Pages Continue

4368-618: The collapse of the Russian Empire , Bessarabia united with Romania (1918–1940, 1941–1944); the district was the center of Cahul County . In 1940, after the Molotov–Ribbentrop Treaty , Basarabia was occupied by the USSR . In 1991, as a result of the proclamation of Independence of Moldova , Cahul County was integrated into this country (1991–2003). In 2003, Cahul became an administrative unit of Moldova . Cahul district

4472-508: The drainage basin of the Himalayan rivers. India , China , Pakistan , Bangladesh , Nepal and Myanmar could experience floods followed by droughts in coming decades. More than 150 districts in India are drought vulnerable, mostly concentrated in the state of Rajasthan, Gujarat, Madhya Pradesh and its adjoining Chhattisgarh, Uttar Pradesh, northern Karnataka and adjoining Maharashtra of

4576-522: The economy developed in agriculture , winery , and trade , along with an increase in population . On August 1, 1770, near Cahul lake, the Battle of Cahul took place ( Russo-Turkish War, 1768-1774 ). It was the most important land battle of the Russo-Turkish War and one of the largest battles of the 18th century. In 1812, after the Russo-Turkish War, there was an intense russification of

4680-440: The genus Homo , and possibly by the earlier partly contemporaneous genera Australopithecus and Paranthropus . Bone tools have been discovered that were used during this period as well but these are rarely preserved in the archaeological record . The Stone Age is further subdivided by the types of stone tools in use. The Stone Age is the first period in the three-age system frequently used in archaeology to divide

4784-500: The geologic time scale : The succession of these phases varies enormously from one region (and culture ) to another. The Paleolithic or Palaeolithic (from Greek: παλαιός, palaios , "old"; and λίθος, lithos , "stone" lit. "old stone", coined by archaeologist John Lubbock and published in 1865) is the earliest division of the Stone Age. It covers the greatest portion of humanity's time (roughly 99% of "human technological history", where "human" and "humanity" are interpreted to mean

4888-518: The Horn of Africa during the period 2020–2023 leading to the third longest and most widespread drought on record with dire implications for food security (see Horn of Africa drought (2020–present) ). Conversely, other parts experienced extreme floods, e.g., the 2020 East Africa floods in Ethiopia, Rwanda, Kenya, Burundi, and Uganda, and the 2022 floods in South Sudan. A key feature in the region

4992-541: The Nile valley. Consequently, they proposed a new system for Africa, the Three-stage System. Clark regarded the Three-age System as valid for North Africa; in sub-Saharan Africa, the Three-stage System was best. In practice, the failure of African archaeologists either to keep this distinction in mind, or to explain which one they mean, contributes to the considerable equivocation already present in

5096-521: The Stone Age ended in a given area. In Europe and North America, millstones were in use until well into the 20th century, and still are in many parts of the world. The terms "Stone Age", "Bronze Age", and "Iron Age" are not intended to suggest that advancements and time periods in prehistory are only measured by the type of tool material, rather than, for example, social organization , food sources exploited, adaptation to climate, adoption of agriculture, cooking, settlement , and religion. Like pottery ,

5200-407: The Stone Age has never been limited to stone tools and archaeology, even though they are important forms of evidence. The chief focus of study has always been on the society and the living people who belonged to it. Useful as it has been, the concept of the Stone Age has its limitations. The date range of this period is ambiguous, disputed, and variable, depending upon the region in question. While it

5304-649: The Stone Age thus could appear there without transitions. The burden on African archaeologists became all the greater, because now they must find the missing transitions in Africa. The problem is difficult and ongoing. After its adoption by the First Pan African Congress in 1947, the Three-Stage Chronology was amended by the Third Congress in 1955 to include a First Intermediate Period between Early and Middle, to encompass

SECTION 50

#1732797519125

5408-466: The Stone Age. In Sub-Saharan Africa, however, iron-working technologies were either invented independently or came across the Sahara from the north (see iron metallurgy in Africa ). The Neolithic was characterized primarily by herding societies rather than large agricultural societies, and although there was copper metallurgy in Africa as well as bronze smelting, archaeologists do not currently recognize

5512-478: The ability of the land to capture and hold water. In arid climates, the main source of erosion is wind. Erosion can be the result of material movement by the wind. The wind can cause small particles to be lifted and therefore moved to another region (deflation). Suspended particles within the wind may impact on solid objects causing erosion by abrasion (ecological succession). Wind erosion generally occurs in areas with little or no vegetation, often in areas where there

5616-526: The absence of water − which is difficult to monitor and define. By the early 1980s, over 150 definitions of "drought" had already been published. The range of definitions reflects differences in regions, needs, and disciplinary approaches. There are three major categories of drought based on where in the water cycle the moisture deficit occurs: meteorological drought, hydrological drought, and agricultural or ecological drought. A meteorological drought occurs due to lack of precipitation . A hydrological drought

5720-540: The decisions of the Pan-African Congress on Prehistory , which meets every four years to resolve the archaeological business brought before it. Delegates are actually international; the organization takes its name from the topic. Louis Leakey hosted the first one in Nairobi in 1947. It adopted Goodwin and Lowe's 3-stage system at that time, the stages to be called Early, Middle and Later. The problem of

5824-448: The destruction of cropland productivity. This can result in diminished crop growth or yield productions and carrying capacity for livestock . Drought in combination with high levels of grazing pressure can function as the tipping point for an ecosystem, causing woody encroachment . Water stress affects plant development and quality in a variety of ways: firstly drought can cause poor germination and impaired seedling development. At

5928-496: The discovery of these "Lomekwian" tools, the oldest known stone tools had been found at several sites at Gona, Ethiopia , on sediments of the paleo- Awash River , which serve to date them. All the tools come from the Busidama Formation, which lies above a disconformity , or missing layer, which would have been from 2.9 to 2.7  mya . The oldest sites discovered to contain tools are dated to 2.6–2.55 mya. One of

6032-548: The early Stone Age, when species prior to Homo may have manufactured tools. According to the age and location of the current evidence, the cradle of the genus is the East African Rift System, especially toward the north in Ethiopia , where it is bordered by grasslands . The closest relative among the other living primates , the genus Pan , represents a branch that continued on in the deep forest, where

6136-400: The first to transition away from hunter-gatherer societies into the settled lifestyle of inhabiting towns and villages as agriculture became widespread . In the chronology of prehistory, the Neolithic era usually overlaps with the Chalcolithic ("Copper") era preceding the Bronze Age. The Stone Age is contemporaneous with the evolution of the genus Homo , with the possible exception of

6240-731: The genus Homo ), extending from 2.5 or 2.6 million years ago, with the first documented use of stone tools by hominins such as Homo habilis , to the end of the Pleistocene around 10,000 BC. The Paleolithic era ended with the Mesolithic , or in areas with an early neolithisation , the Epipaleolithic . At sites dating from the Lower Paleolithic Period (about 2,500,000 to 200,000 years ago), simple pebble tools have been found in association with

6344-533: The grasslands of the rift, Homo erectus , the predecessor of modern humans, found an ecological niche as a tool-maker and developed a dependence on it, becoming a "tool-equipped savanna dweller". The oldest indirect evidence found of stone tool use is fossilised animal bones with tool marks; these are 3.4 million years old and were found in the Lower Awash Valley in Ethiopia. Archaeological discoveries in Kenya in 2015, identifying what may be

SECTION 60

#1732797519125

6448-589: The hand-axe tradition, there developed a distinct and very different stone-tool industry, based on flakes of stone: special tools were made from worked (carefully shaped) flakes of flint. In Europe, the Clactonian industry is one example of a flake tradition. The early flake industries probably contributed to the development of the Middle Paleolithic flake tools of the Mousterian industry , which

6552-459: The health of people who are directly exposed to this phenomenon (excessive heat waves ). Droughts can also cause limitations of water supplies, increased water pollution levels, high food-costs, stress caused by failed harvests, water scarcity , etc. Reduced water quality can occur because lower water-flows reduce dilution of pollutants and increase contamination of remaining water sources. This explains why droughts and water scarcity operate as

6656-419: The horrific drought in 2010–2011 in both duration and severity. More than 150 districts in India are drought vulnerable, mostly concentrated in the state of Rajasthan, Gujarat, Madhya Pradesh and its adjoining Chhattisgarh, Uttar Pradesh, northern Karnataka and adjoining Maharashtra of the country. Throughout history, humans have usually viewed droughts as disasters due to the impact on food availability and

6760-504: The intermediate periods were gone, the search for the transitions continued. In 1859 Jens Jacob Worsaae first proposed a division of the Stone Age into older and younger parts based on his work with Danish kitchen middens that began in 1851. In the subsequent decades this simple distinction developed into the archaeological periods of today. The major subdivisions of the Three-age Stone Age cross two epoch boundaries on

6864-645: The journal Annals of the South African Museum . By then, the dates of the Early Stone Age, or Paleolithic , and Late Stone Age, or Neolithic ( neo = new), were fairly solid and were regarded by Goodwin as absolute. He therefore proposed a relative chronology of periods with floating dates, to be called the Earlier and Later Stone Age. The Middle Stone Age would not change its name, but it would not mean Mesolithic . The duo thus reinvented

6968-507: The lack of water in the plants, bushfires are common. Since water vapor becomes more energetic with increasing temperature, more water vapor is required to increase relative humidity values to 100% at higher temperatures (or to get the temperature to fall to the dew point). Periods of warmth quicken the pace of fruit and vegetable production, increase evaporation and transpiration from plants, and worsen drought conditions. The El Niño–Southern Oscillation (ENSO) phenomenon can sometimes play

7072-638: The late 19th and early 20th centuries CE, who adapted the three-age system to their ideas, hoped to combine cultural anthropology and archaeology in such a way that a specific contemporaneous tribe could be used to illustrate the way of life and beliefs of the people exercising a particular Stone-Age technology. As a description of people living today, the term Stone Age is controversial. The Association of Social Anthropologists discourages this use, asserting: To describe any living group as 'primitive' or 'Stone Age' inevitably implies that they are living representatives of some earlier stage of human development that

7176-579: The literature. There are in effect two Stone Ages, one part of the Three-age and the other constituting the Three-stage. They refer to one and the same artifacts and the same technologies, but vary by locality and time. The three-stage system was proposed in 1929 by Astley John Hilary Goodwin, a professional archaeologist, and Clarence van Riet Lowe , a civil engineer and amateur archaeologist, in an article titled "Stone Age Cultures of South Africa" in

7280-417: The local economy . Annual dry seasons in the tropics significantly increase the chances of a drought developing, with subsequent increased wildfire risks. Heat waves can significantly worsen drought conditions by increasing evapotranspiration . This dries out forests and other vegetation, and increases the amount of fuel for wildfires. Drought is a recurring feature of the climate in most parts of

7384-420: The majority of humankind has left behind. In the 1920s, South African archaeologists organizing the stone tool collections of that country observed that they did not fit the newly detailed Three-Age System. In the words of J. Desmond Clark : It was early realized that the threefold division of culture into Stone, Bronze and Iron Ages adopted in the nineteenth century for Europe had no validity in Africa outside

7488-466: The most striking circumstances about these sites is that they are from the Late Pliocene , where prior to their discovery tools were thought to have evolved only in the Pleistocene . Excavators at the locality point out that: ... the earliest stone tool makers were skilled flintknappers  ... The possible reasons behind this seeming abrupt transition from the absence of stone tools to

7592-535: The native population during the occupation of Basarabia by the Russian Empire during this period (1812–1856, 1878–1917). Between 1813 and 1850, the Tsarist government colonized some of the region with Russians , Ukrainians , Bulgarians , and Gagauz . These ethnic groups now constitute 21% of the population of the district. In 1856–1878, the district became part of Romania after the Crimean War . After

7696-415: The negative effect on the health of people directly exposed to this phenomenon (excessive heat waves), high food costs, stress caused by failed harvests, water scarcity , etc. Drought can also lead to increased air pollution due to increased dust concentrations and wildfires . Prolonged droughts have caused mass migrations and humanitarian crisis . Examples for regions with increased drought risks are

7800-524: The north (Plateau Tigheci), and 5 to 10 m (16 to 33 ft) near the Danube . There is a mild amount of Erosion . The climate is temperate continental . The region is considered the most arid and hottest in Moldova . Temperatures are 2 to 3 °C (36 to 37 °F) higher than the other regions. The amount of precipitation during the year is uneven (400 to 550 millimetres [16 to 22 in]) and there are often periods of drought . Animal life includes typical European steppe fauna , with

7904-515: The occurrence of droughts has increased as a result of the increase in temperature and atmospheric evaporative demand . In addition, increased climate variability has increased the frequency and severity of drought events. Moreover, the occurrence and impact of droughts are aggravated by anthropogenic activities such as land use change and water management and demand. The IPCC Sixth Assessment Report also pointed out that "Warming over land drives an increase in atmospheric evaporative demand and in

8008-532: The oldest evidence of hominin use of tools known to date, have indicated that Kenyanthropus platyops (a 3.2 to 3.5-million-year-old Pliocene hominin fossil discovered in Lake Turkana, Kenya, in 1999) may have been the earliest tool-users known. The oldest stone tools were excavated from the site of Lomekwi 3 in West Turkana , northwestern Kenya, and date to 3.3 million years old. Prior to

8112-449: The presence of mammals , such as foxes , hedgehogs , deer , wild boar , polecat , wild cat , ermine and others. Birds include partridges , crows , eagles , starling and swallow . Forests occupy 11.5% of the district. They are made up of tree species such as acacia , oak , ash , hornbeam , linden , maple and walnut . Other plant life includes wormwood , knotweed , fescue and nettle . The hydrographic network

8216-626: The presence thereof include ... gaps in the geological record. The species that made the Pliocene tools remains unknown. Fragments of Australopithecus garhi , Australopithecus aethiopicus , and Homo , possibly Homo habilis , have been found in sites near the age of the Gona tools. In July 2018, scientists reported the discovery in China of the known oldest stone tools outside Africa, estimated at 2.12 million years old. Innovation in

8320-581: The primates evolved. The rift served as a conduit for movement into southern Africa and also north down the Nile into North Africa and through the continuation of the rift in the Levant to the vast grasslands of Asia. Starting from about 4 million years ago ( mya ) a single biome established itself from South Africa through the rift, North Africa, and across Asia to modern China. This has been called "transcontinental 'savannahstan ' " recently. Starting in

8424-543: The rainforest towards a " tipping point " where it would irreversibly start to die. It concludes that the rainforest is on the brink of being turned into savanna or desert , with catastrophic consequences for the world's climate. According to the WWF , the combination of climate change and deforestation increases the drying effect of dead trees that fuels forest fires. The 1997–2009 Millennium Drought in Australia led to

8528-543: The reduction in plant growth and yields. Another factor influencing reduced plant growth and yields include the allocation of resources; following drought stress plants will allocate more resources to roots to aid in water uptake increasing root growth and reducing the growth of other plant parts while decreasing yields. The most negative impacts of drought for humans include crop failure , food crisis , famine, malnutrition, and poverty , which lead to loss of life and mass migration of people. There are negative effects on

8632-605: The remains of what may have been the earliest human ancestors. A somewhat more sophisticated Lower Paleolithic tradition, known as the Chopper chopping tool industry, is widely distributed in the Eastern Hemisphere. This tradition is thought to have been the work of the hominin species named Homo erectus . Although no such fossil tools have yet been found, it is believed that H. erectus probably made tools of wood and bone as well as stone. About 700,000 years ago,

8736-487: The rest of Asia became post-Stone Age societies by about 4000 BC. The proto-Inca cultures of South America continued at a Stone Age level until around 2000 BC, when gold, copper, and silver made their entrance. The peoples of the Americas notably did not develop a widespread behavior of smelting bronze or iron after the Stone Age period, although the technology existed. Stone tool manufacture continued even after

8840-451: The rest of society. People have viewed drought as a natural disaster or as something influenced by human activity , or as a result of supernatural forces. The IPCC Sixth Assessment Report defines a drought simply as "drier than normal conditions". This means that a drought is "a moisture deficit relative to the average water availability at a given location and season". According to National Integrated Drought Information System ,

8944-564: The same time plant growth relies on cellular division, cell enlargement, and differentiation. Drought stress impairs mitosis and cell elongation via loss of turgor pressure which results in poor growth. Development of leaves is also dependent upon turgor pressure, concentration of nutrients, and carbon assimilates all of which are reduced by drought conditions, thus drought stress lead to a decrease in leaf size and number. Plant height, biomass, leaf size and stem girth has been shown to decrease in maize under water limiting conditions. Crop yield

9048-486: The scientific study of the lithic reduction of the raw materials and methods used to make the prehistoric artifacts that are discovered. Much of this study takes place in the laboratory in the presence of various specialists. In experimental archaeology , researchers attempt to create replica tools, to understand how they were made. Flintknappers are craftsmen who use sharp tools to reduce flintstone to flint tool . In addition to lithic analysis, field prehistorians use

9152-411: The severity of drought events" and "Increased atmospheric evaporative demand increases plant water stress, leading to agricultural and ecological drought". There is a rise of compound warm-season droughts in Europe that are concurrent with an increase in potential evapotranspiration . Higher temperatures increase evaporation. This dries the soil and increases plant stress . Agriculture suffers as

9256-458: The shape have been called choppers, discoids, polyhedrons, subspheroid, etc. To date no reasons for the variants have been ascertained: From a functional standpoint, pebble cores seem designed for no specific purpose. Drought A drought is a period of drier-than-normal conditions. A drought can last for days, months or years. Drought often has large impacts on the ecosystems and agriculture of affected regions, and causes harm to

9360-466: The short rains from October to December. The frequent occurrence of hydrological extremes, like droughts and floods , harms the already vulnerable population suffering from severe poverty and economic turmoil. Droughts prompted food shortages for example in 1984–85 , 2006 and 2011 . The Eastern African region experiences the impacts of climate change in different forms. For instance, below-average rainfall occurred for six consecutive rainy seasons in

9464-450: The spatial and temporal changes and variability in drought duration, severity, and magnitude at a much finer scale. This supports the development of site-specific adaptation measures. The application of multiple indices using different datasets helps to better manage and monitor droughts than using a single dataset, This is particularly the case in regions of the world where not enough data is available such as Africa and South America. Using

9568-403: The technique of smelting ore is regarded as the end of the Stone Age and the beginning of the Bronze Age . The first highly significant metal manufactured was bronze , an alloy of copper and tin or arsenic , each of which was smelted separately. The transition from the Stone Age to the Bronze Age was a period during which modern people could smelt copper, but did not yet manufacture bronze,

9672-533: The timeline of human technological prehistory into functional periods, with the next two being the Bronze Age and the Iron Age , respectively. The Stone Age is also commonly divided into three distinct periods: the earliest and most primitive being the Paleolithic era; a transitional period with finer tools known as the Mesolithic era; and the final stage known as the Neolithic era. Neolithic peoples were

9776-450: The transitions in archaeology is a branch of the general philosophic continuity problem, which examines how discrete objects of any sort that are contiguous in any way can be presumed to have a relationship of any sort. In archaeology, the relationship is one of causality . If Period B can be presumed to descend from Period A, there must be a boundary between A and B, the A–B boundary. The problem

9880-584: The tropics, distinct, wet and dry seasons emerge due to the movement of the Intertropical Convergence Zone or Monsoon trough . The dry season greatly increases drought occurrence, and is characterized by its low humidity, with watering holes and rivers drying up. Because of the lack of these watering holes, many grazing animals are forced to migrate due to the lack of water in search of more fertile lands. Examples of such animals are zebras , elephants , and wildebeest . Because of

9984-472: The typology of the stone tools combined with the relative sequence of the types in various regions provide a chronological framework for the evolution of humanity and society. They serve as diagnostics of date, rather than characterizing the people or the society. Lithic analysis is a major and specialised form of archaeological investigation. It involves the measurement of stone tools to determine their typology, function and technologies involved. It includes

10088-414: The uptake of nutrients from the soil, and for the transport of nutrients throughout the plant: drought conditions limit these functions leading to stunted growth. Drought stress also causes a decrease in photosynthetic activity in plants due to the reduction of photosynthetic tissues, stomatal closure, and reduced performance of photosynthetic machinery. This reduction in photosynthetic activity contributes to

10192-465: The west Pacific and the Indian Ocean to the east Pacific, it causes extensive drought in the western Pacific. Singapore experienced the driest February in 2014 since records began in 1869, with only 6.3 mm of rain falling in the month and temperatures hitting as high as 35 °C on 26 February. The years 1968 and 2005 had the next driest Februaries, when 8.4 mm of rain fell. Globally,

10296-725: The whole Murray-Darling basin if it did not receive sufficient water by October 2008. Australia could experience more severe droughts and they could become more frequent in the future, a government-commissioned report said on July 6, 2008. Australian environmentalist Tim Flannery , predicted that unless it made drastic changes, Perth in Western Australia could become the world's first ghost metropolis , an abandoned city with no more water to sustain its population. The long Australian Millennial drought broke in 2010. East Africa , including for example Ethiopia, Eritrea, Kenya, Somalia, South Sudan, Sudan, Tanzania, and Uganda, has

10400-513: The wind erosion of loess. In 2005, parts of the Amazon basin experienced the worst drought in 100 years. A 2006 article reported results showing that the forest in its present form could survive only three years of drought. Scientists at the Brazilian National Institute of Amazonian Research argue in the article that this drought response, coupled with the effects of deforestation on regional climate, are pushing

10504-663: The world, becoming more extreme and less predictable due to climate change , which dendrochronological studies date back to 1900. There are three kinds of drought effects, environmental, economic and social. Environmental effects include the drying of wetlands , more and larger wildfires, loss of biodiversity . Economic impacts of drought result due to negative disruptions to agriculture and livestock farming (causing food insecurity ), forestry, public water supplies , maritime navigation (due to e.g.: lower water levels), electric power supply (by affecting hydropower systems) and impacts on human health. Social and health costs include

10608-449: Was rural . Footnote : * There is an ongoing controversy regarding the ethnic identification of Moldovans and Romanians. In terms of economic development, Cahul district is characterized by the development of industries based primarily on various raw materials . There are 11 private wineries and 8 bakeries . In the cheese industry, there is a factory, collecting cereal and processing vegetables and fruit . Light industry

10712-458: Was a broad prehistoric period during which stone was widely used to make stone tools with an edge, a point, or a percussion surface. The period lasted for roughly 3.4 million years and ended between 4000 BC and 2000 BC, with the advent of metalworking . It therefore represents nearly 99.3% of human history. Though some simple metalworking of malleable metals, particularly the use of gold and copper for purposes of ornamentation,

10816-607: Was known in the Stone Age, it is the melting and smelting of copper that marks the end of the Stone Age. In Western Asia , this occurred by about 3000 BC, when bronze became widespread. The term Bronze Age is used to describe the period that followed the Stone Age, as well as to describe cultures that had developed techniques and technologies for working copper alloys (bronze: originally copper and arsenic, later copper and tin) into tools, supplanting stone in many uses. Stone Age artifacts that have been discovered include tools used by modern humans, by their predecessor species in

#124875