3.1Climate

In 2002, climate in the Three Gorges reservoir area was relatively warm, with the annual average temperature being 17.9℃, 0.4℃ higher than normal years. Rainfall in most places was normal or a little more with the annual average rainfall of 1254mm, about 10% more than normal years. Rainfall in the flood season was normal, but not balanced in time and space. Major climatic disasters in the reservoir area were low temperature and rain in spring and August, heat and drought in summer, storms and induced floods, mud-rock flows and hails.

Table 3-1 Monitoring Results of Meteorological Elements in Meteorological Stations in the Three Gorges Reservoir Area in 2002

Name of Station	Average	Comparative	Rainfall	Evaporation	Average	Sunshine Hours	Foggy	Thunder
	Temperature	Humidity	(mm)	(mm)	Wind speed	(h)	Days	Storm Days
	(℃)	(%)			(m/s)		(d)	(d)
Chongqing	18.8	81	1421	606.5	1.7	1145.6	29	41
Changshou	17.9	82	1232.3	1164.1	1.4	1331.4	48	49
Fuling	18.5	80	1216.2	693.2	0.4	1334.7	92	48
Wanzhou	18.6	80	1072.7	667.7	0.5	1413.7	26	54
Fengjie	16.5	75	1290.6	825.2	2	1733.1	27	47
Wushan	18.3	71	1071.8	1583.3	1.6	1735.5	8	44
Badong	17.4	71	1097.8	1577.7	1.9	1526.7	72	48
Zigui	16.9	77	1682.2	1151.6	1.1	1735	0	41
Bahekou	17.5	80	1442.6	1234	1.6	1371.6	1	34
Yichang	17.5	79	1632.1	1323.1	1.2	1523.4	11	39

The average rainfall in the reservoir area was 1070-1682mm. Its spatial and temporal distribution features were: there was relatively much rainfall in the east and west parts of the reservoir area and basically normal in the middle part. Rainfall in winter of 2001/2002 and spring of 2002 was continuously much, normal in summer and obviously less in autumn. Heavy rains and rainstorms were concentrated in spring and summer. Rainfall between March and August totaled 866 mm, accounting for 70% of the annual rainfall in the reservoir area. Rainfall peaked in May, about 40% more than that of the same period of normal years. Rainfall distribution in the flood season (between June and August) was imbalanced. Rainfall was relatively much in June and August and less in July. Average rainfall in autumn in the reservoir area was more than 40% less than normal years, which was good to river damming flowing for leading open dykes.

In 2002, climate in the Three Gorges reservoir area was relatively warm, which was more so in the west part than in the east part. Relatively high temperature was the most obvious in January, February, June and July. In February, temperature measured in all representative meteorological stations was over 2.0℃ higher than normal years. Yichang had a more than 3.5℃ higher temperature in two successive months and an abnormal warm winter. Most places went through broil weather in June and July. Days with temperature higher than or equal to 35℃ amounted to 26-28 in Badong, Yichang, Zigui and Bahekou. Most places in Chongqing had an extremely high temperature of 39℃ and over 40℃ in parts of the area. Temperature in April, May and August was relatively low at large and the most so in May. The Average temperature measured in most representative stations in may was 1-2℃ lower than that of the same period in normal years and 2.1-2.5℃ lower in Fengjie, Wushanand Badong. Between late April and May, most places experienced typically unusual coal spell in an otherwise warm spring. In August, stations in the reservoir area all measured a temperature 1-2℃ lower than that of the same period of normal years and nearly 3℃ lower in Fengjie and Wushan. The summer was featured with notably low temperature.

Chart 3-1 Rainfall Distribution Curve in June, July and August of 2002 in the Three Gorges Reservoir Area

In 2002, the average wind speed in the Three Gorges reservoir area was 1.3 m/s, which as close to that of normal years. In all stations, seasonal changes and monthly changes of average wind speed were not much.

Average foggy days in the Three Gorges reservoir area numbered 34.9, 0.8 days more than normal years. The spatial and temporal distribution features were: foggy days in Wanzhou and areas west of it mainly occurred in autumn and winter; and foggy days in areas east of Wanzhou occurred mostly in winter and spring or spring and summer. Fuling continued to be the area with the most of foggy days after 2001. No foggy day occurred in Zigui and only one day in Bahekou.

The average comparative humidity in the Three Gorges reservoir area was 77%, close to that of normal years and changing little in different seasons. Comparative humidity in the west part was higher than that in the east part. The average evaporation in the reservoir area was 1055 mm, 15% less than that of normal years. Evaporation went down from the east to the west. In terms of seasonal distribution, it was continuous lower in winter, spring and summer, which was especially so in summer in Chongqing with less than half of that of normal years in the same period in June, July and August. Evaporation peaked in autumn, with the seasonal average 10% higher than that of normal years.

In 2002, major meteorological disasters in the Three Gorges reservoir area were the cold spell in spring, low temperature and continuous rain in August and high temperature and drought, rainstorms and hails in summer.

Chart 3-2 Evaporation Distribution Curve in June, July and August of 2002 in the Three Gorges Reservoir Area

In spring, most places in the reservoir area were affected by strong cold currents with three spells of low temperature and continuous rain. The longest period was in the latter part of the second ten days of April and the first ten days of May, with over successive ten days of rain. Average daily temperature measured in most stations fell to below 12℃, which featured the typical cold spell in an otherwise warm spring and May. Continuous cold weather and rain had some impacts on agriculture in the reservoir area: harvests of crops sown in late spring were delayed; the rape and wheat germinated and went moldy to different degrees; paddy seedlings turned green slowly and some rotted in the fields; vegetable growth was hampered.

In winter, spring and summer, most places in the reservoir area experienced relatively much rainfall. Strong convection weather occurred frequently, which caused a number of heavy rainstorms and storm induced disasters such as floods, landslips and mud-rock flows. These disasters had an impact on 13.2766 million people, directly affected 8.4978 million people and caused direct economic losses of 2.31 billion yuan.

In July, the east part of the reservoir area experienced higher temperature. Especially in the second and last ten days of July hot weather occurred of which the highest temperature in the daytime of over ten days in succession exceeded 35℃ (39.6℃ in parts of the area). Rainfall was less and parts of the area were subject to serious drought. High temperature and drought in Changshou, Wanzhou, Fengjie, Fengdu and Yichang caused difficulty in drinking water supply for human and livestock and serious losses to agriculture.

Besides, disastrous weather such as heavy frog, hazes, snow and freezing, hail and thunderstorm and lightning occurred in parts of the reservoir area and also caused losses to industrial and agricultural production, traffic and transportation and electric transmission lines, which affected people's normal life.

In winter, spring and summer, most places in the reservoir area experienced relatively much rainfall. Strong convection weather occurred frequently, which caused a number of heavy rainstorms and storm induced disasters such as floods, landslips and mud-rock flows. These disasters had an impact on 13.2766 million people, directly affected 8.4978 million people and caused direct economic losses of 2.31 billion yuan.

In July, the east part of the reservoir area experienced higher temperature. Especially in the second and last ten days of July hot weather occurred of which the highest temperature in the daytime of over ten days in succession exceeded 35℃ (39.6℃ in parts of the area). Rainfall was less and parts of the area were subject to serious drought. High temperature and drought in Changshou, Wanzhou, Fengjie, Fengdu and Yichang caused difficulty in drinking water supply for human and livestock and serious losses to agriculture.

Besides, disastrous weather such as heavy frog, hazes, snow and freezing, hail and thunderstorm and lightning occurred in parts of the reservoir area and also caused losses to industrial and agricultural production, traffic and transportation and electric transmission lines, which affected people's normal life.

3.2Terrestrial Plants

In 2002, supplementary surveys were conducted on plant species in the Three Gorges reservoir area and no new plant species was discovered. Surveys on wild plant resources and appraisal and analysis on collected specimen showed that the Three Gorges reservoir area was endowed with abundant terrestrial plant resources and extremely rich biodiversity. Plant families in the reservoir area accounted for over half of the national total; plant genera accounted for over 40% of the national total and plant species accounted for 22% of the national total.

According to preliminary analysis, forest vegetation in the Three Gorges reservoir area could be classified into 15 community groups and 76 communities. Living types classification of spermatophyte based on genus showed that there were 299 genera of arbor (among which were 112 genera of evergreen arbor and 187 genera of defoliating arbor), 245 genera of shrubs and semi-shrubs, 801 genera of herbage, 75 genera of vine and 8 genera of bamboo, accounting for 20.9%, 17.2%, 56.1%, 5.3% and 0.6% of the total genera in the area respectively.

At present, there were 150 species of plants in the Three Gorges reservoir area in the list for national protection and 51 species of rare and endangered plants, accounting for 13.1% of the 388 national level species. Among them,8 were endangered species, 19 were rare species and 24 were species turning endangered. Species distributed in areas less than altitude of 400 m were mainly Magnolia Officinalis, Phoebe Zhennan, Adiantum reniforme var. Sinense and Glycine soja. In 2002, monitoring was carried out on 20 plant species of national protection such as Davidia involucrata and Cibotium barometz, which showed that these plants were growing well.

3.3Terrestrial Animals

In 2002, monitoring and surveys on birds recorded 391 species in accumulation, with 13 ones over 2001's record of 378 species and closer to the number deduced from theoretic analysis on bird species in the reservoirarea (about 400 species).

In monitoring and surveys on reptiles, spots where Protobothrops jerdonii were discovered expanded from 1 to 3. Record of one alien species-spotted deer in Minor Shennongjia in Badong County was added into beast species, which was the wild strain coming from domesticated individuals set in the wild from the Shennongjia Nature Reserve more than ten years ago.

Although there was a quite large area of insulation belt between golden monkeys' habitat in Minor Shennongjia of Badong County and Shennongjia, a narrow habitat "corridor" existed in both the east and west ends which golden monkeys could go through. This formed a habitat that could be jointly used by a number of golden monkey populations in the south of Shennongjia and Minor Shennongjia. The number of golden monkeys using this area jointly and those living in habitat in the south of Shennongjia was no less than 600~800.

Presbytis francoisi population was discovered in the Furong River Valley in the border area of Wulong County and Pengshui County of Chongqing was made in the end of December of 2000. Years of monitoring and surveys after that revealed that places where Presbytis francoisi looked for food, and slept, and collected minerals to eat were mostly located in areas at altitude of 250-350 m.

Besides, mandarin ducks were observed in three spots in Zigui Section, Zhong County Section and Wushan Section in the main course of the Yangtze River.

3.4 Fishery Resources and Environment

3.4.1 Fishery resources

In 2002, the natural fishing catch in the Three Gorges reservoir area, the section down the dam, Dongting Lake, Poyang Lake and the estuary area was 78,459 tons, 17% over that of 2001.Catch of common carp, crucian carp and tapertail anchovy rose to some extent, that of the four major home fish, bronze gudgeon and largemouth bronze remained the same with the previous year and that of eel and Chinese turtle crab dropped.

Reservoir area: in 2002, the natural fishing catch in the Three Gorges reservoir area was 2,935 tons, a little less than that of 2001. The composition of the catch was 596 tons of river Parasilutus asotus, 548 tons of bronze gudgeon, 402 tons of largemouth bronze gudgeon, 362 tons of common carp, 251 tons of Pseudobagrus, 230 tons of Leiocassis longirostris, 217 tons of grass carp and 177 tons of silver carp.

Monitoring of fishing catch showed that six fishes including bronze gudgeon, largemouth bronze gudgeon, river Parasilutus asotus, common carp, Pseudobagrus and Leiocassis longirostris accounted for 81% of the total catch, remaining the major economic fishes in the reservoir area.

Section down the dam: in 2002, the natural fishing catch in the section down the dam was 2,800 tons, a little less than that of 2001. The composition of the catch was 1077 tons of bronze gudgeon, 290 tons of river Parasilutus asotus, 489 tons of common carp, 150 tons of Pseudobagrus, 109 tons of grass carp, 142 tons of silver carp, 51 tons of snail carp and 34 tons of fathead.

Monitoring result on the catch composition was different from that of 2001. Bronze gudgeon accounted for 38% of the total, becoming the main economic fish in section down the dam. Biological compositions of the catch showed that grass carp and common carp caught were small and young.

Spawning sites of the "Four Major Home fishes": Monitoring result in May and June 2002 showed that the fry run-off amount of the "four major home fishes" in Yunyang section of the reservoir area was 356 million tails; that in Sanzhou section of Jianli was 1.9 billion tails, with little change compared with 2001; and fry run-off amount in Wuxue section was 2.225 billion tails.

Dongting Lake: in 2002, the total catch of the entire lake was 32,564 tons, 9% over that of 2001. There were 47 spawning sites of common carp and crucian carp, covering an area of 305 km2. There were 215,000 tails of spawning common carp, weighting at 388 tons and their spawn amount reaching 6.025 billion, 16%, 11% and 7% over the previous year respectively. There were 298,000 tails of spawning crucian carp, weighting at 388 tons and their spawn amount reaching 3.936 billion, 7%, 5% and 5% over the previous year respectively.

There were 34 feeding sites, covering an area of 824 km². Among them, 13 were in east Dongting Lake, being 494 km²; 16 were in south Dongting Lake, being 131 km² and 5 were in west Dongting Lake, being 199 km². Main fishes in the feeding sites were common carp, crucian carp, silver carp, fathead, snail carp, grass carp, river Parasilurus asotus and Siniperca chuatsi and the amount of the feeding community was 7.2 billion tails.

Poyang Lake: the total catch of the entire lake in 2002 was 39,300 tons, 31.0% over that of 2001. There were 33 spawning sites and the spawn amount was 5 billion, 23% over the previous year. Among these, the spawn amount was 1.953 billion in the southern part, 1.627 billion in the eastern part and 1.42 billion in the western part.

The spawning sites for common carp and crucian carp in the Poyang Lake in 2002 covered an area of 660 km², among which 300 km² were in the southern part, 190 km² were in the eastern part and 170 km2 were in the western part. The feeding sites covered an area of about 600 km², 21% over that of 2001.

Estuary area: in 2002, biological indicators of tapertail anchovy were all lower than that of 2001. The total output and total value of individual ship in the entire flood season were both higher than that of 2001 and the total catch was 857.81 tons, much higher than that of 2001.

In 2002, catch intensity of parent crabs was relatively low. The catch amount was 768.65 kg, only 20% of that in 2001 and various biological indicators continued to decrease. From 1999 to 2002, output of parent crabs was on the decrease year by year. Continuous decrease in the total catch and biological indicators showed that the perspective of parent crab resources was not optimistic.

In 2002, the output of crabling in the estuary area was low, with almost no output in the southern part and the catch in the northern part mainly concentrated in areas near the beach and in the harbor. The number of eel catching ship dropped significantly. The total output was 12.061 million tails (about 1724.72 kg), a large reduction compared with 2001. But total output of individual ship was not notably reduced.

3.4.2 Fishery environment

In 2002, Seven monitoring stations (Yibin Station, Banan Station, Wanzhou Station, Jingzhou Station, Yueyang Station, Lake Outlet Station and Estuary Station) were set up in the mainstream of the Yangtze River, Dongting Lake and the estuary area and monitoring was carried out on water quality of key fishery water bodies in the Yangtze River basin. The result showed that according to the Fishery Water Quality Standards (GB11607－89), water quality of key fishery water bodies in the Yangtze River basin was sound on the whole, which generally could meet the growing and breeding requirements of fishes. But parts of the water bodies were polluted to some extent,with the major pollutants exceeding standard being total copper, oil, volatile phenol and non-ion ammonia.

Major pollutants exceeding the standards in the fishery water bodies were total copper, oil and non-ion ammonia in the upper reaches of the Yangtze River In 2002.Monitoring values on total copper in the three functional periods of fishes all exceeded the standard, with the exceeding rate being 100% in Yibin. Monitoring values on oils in Banan exceeded the standard in breeding and rearing periods, with the exceeding rate being 100%. Monitoring values on non-ion ammonia in Wanzhou exceeded the standard in the rearing period, with the exceeding rate being 33.3%.

Major pollutants exceeding the standards in the fishery water bodies in the middle reaches of the Yangtze River were total copper, oils, total zinc, lead and non-ion ammonia. Monitoring which was carried out in 6 water bodies in the fish breading period showed that exceeding rates of total copper and oil were 83.3% and 33.3% respectively and those of non-ion ammonia, total lead and total zinc were all 16.7%. Monitoring which was carried out in 4 water bodies in the fish rearing period showed that exceeding rate of total copper was 100%, those of non-ion ammonia and total lead were both 50.0% and that of total zinc was 25.0%. Monitoring which was carried our in 4 water bodies in the fish wintering period showed that exceeding rates of total copper and total zinc were 75.0% and 25.0% respectively.

Monitoring result on the spawning sites of the four major home fishes in the section from Yichang to Chenglingji of the Yangtze River showed that in May and June of 2002, water temperature ranged from 18.4-26.0℃ in the Jianli section of the Yangtze River. Total copper and non-ion ammonia exceeded the standards in all the monitored sections and oil, total zinc and lead exceeded the standards in parts of the monitored sites in Jianli. Water quality, water temperature, water level and flow change in the spawning sites were suitable for breeding of the four major home fishes.

Major pollutant exceeding the standards in the fishery water bodies of Dongting Lake was total copper, exceeding rates of which in the breeding and wintering periods were 37.5% and 28.6% respectively. Water quality of Dongting Lake was improved to some extent compared with 2001.

Major pollutants exceeding the standards in the estuary area of the Yangtze River were total mercury, volatile phenol, oil and total copper. In the eel season, monitoring values of volatile phenol and oil exceeded the standards with their exceeding rates both being 50.0%. In the tapertail anchovy season, monitoring values of volatile phenol, oil and total mercury exceeded the standards with their exceeding rates being 42.9%, 28.6% and 50.0%. In the winter crab season, monitoring value of total copper exceeded the standard with its exceeding rate being 33.3%.

3.5 Peculiar Fishes and Rare Aquatic Animals

3.5.1 Peculiar fishes in the upper reaches of the Yangtze River

In the two field surveys conducted in spring and autumn of 2002 in Yibin, Hejiang and Mudong sections in the upper reaches and Yichang section in the middle reaches of the Yangtze River, 91 species (sub-species) of fishes were collected. Among them, 24 were peculiar fishes in the upper reaches of the Yangtze River, accounting for 51.0% of the peculiar fish species affected by the Three Gorges Project. Of all species, 43 were observed in Yibin section, including 11 peculiar species; 78 species (sub-species) were observed in Hejiang section including 20 peculiar species (sub-species); 39 species (sub-species) were observed in Mudong section including 9 peculiar species (sub-species); and 57 species were observed in Yichang section including 6 peculiar species (sub-species). Platysmacheilus nudiventris and Sinogastromyzon Sichangensis were observed for the first time after monitoring was carried out in 1997. In the investigated river sections, the number of peculiar species, their distribution scope and their proportion in commercial fishery did not notably change.

3.5.2 Rare fishes and Lipotes vexillifer

In 2002, Chinese sturgeon (Acipenser sinensis) spawned for two times, which were on October 27 and November 9. Spawning sites were confined in the about 5 km section from Gezhou Dam down to Miaozui in Yichang and no spawning was found in the section from Miaozui to Gulaobei (where spawning sites of Chinese sturgeon were found by monitoring in the past). Spawning scale of the first time was larger than that of the second time and the total scale of these two times was notably larger than that in 2001. Fecundation rate of Chinese sturgeon eggs was higher than that of past years. There were 11 fishes eating the eggs, mainly bronze gudgeon, Pelteobagrus vachelli  and largemouth bronze gudgeon.

According to the result of sonar detection, the number of Chinese sturgeon in the section between downstream Gezhou Dam and Zhenjiangge was between 308 and 436 and that in the section between Zhenjiangge and Gulaobei was estimated to be 1395-2141. In 2002, the number of breeding Chinese sturgeon was more than that in 2000 and 2001. The number of breeding Chinese sturgeon distributed in the spawning sites accounted for 16.9-18.1% of that in the section of downstream Gezhou Dam and Gulaobei.

In 2002, mistakenly catch of the rare fishes-Acipenser dabryanus and Psephurus gladius did not taken place in the section from Shangzhongba in Jiaotan Village in Hejiang to Tongqianwan in Wanglong Village in the upper reaches of the Yangtze River. One Myxocyprinus asiaticus weighted at 12 kg was mistakenly caught.   No catch of Chinese paddle fish, River Sturgeon or Chinese sucker was recorded in Yibin and Mudong sections. No activity of Chinese paddle fish was observed in Yichang section in the middle reaches of the Yangtze River. Mistaken catch of one Psephurus gladius was recorded in Nanjing section in the lower reaches of the Yangtze River. No mistaken catch of Chinese sucker was recorded in Yichang section.

In 2002, two Lipotes vexillifer were observed in the Lipotes vexillifer Reserve in Xinluo section of the Yangtze River. More than ten groups of River Dolphins and scores of River Dolphin individuals were observed in the section between Wuhan and Meizixi.

3.6 Agricultural Ecology

3.6.1 Ecological environment of agriculture fields

In 2002, surveys were conducted on 194 towns and villages in 19 counties in the reservoir area with the same survey base as 2001. Investigation results showed that agricultural restructuring was strengthened in the Three Gorges reservoir area. Farmland reversion to forest and grassland was accelerated and agricultural planting and sowing fields dropped greatly in area.  Backup wasteland suitable for agriculture was not much and reversion of slope farmland was sped up. Re-cropping index of farmland was high and agricultural production still concentrated on grain crop cultivation. Soil fertility of agricultural fields in the reservoir area decreased and its heavy metal content was normal.

In 2002, total sowing area in the reservoir area was 567,391 hectare, 8.5% less than that in 2001. Among these, the area of grain crops was 439,856 hectare and that of economic crops was 127,535 hectare, accounting for 77.5% and 22.5% of the total respectively. Compared with 2001, the proportion of economic crops was raised because the area of orange plantations increased and that of grain crops decreased.

Surveys on cultivation of slope farmland showed that ecological rehabilitation focused on farmland reversion to forest and grassland was actively carried out in 14 counties and cities in the reservoir area. The area of slope farmland over 25 degrees reversed to forest and grassland totaled 9361.37 hectare, with an increase of 9.3% compared with that of the 12 counties and cities investigated in 2001.

In terms of cultivation types, paddy fields mainly grew crops with two harvests per year, accounting for 59.6% and 3.8 percentage points less than that of 2001; arid land mainly grew crops with three harvests per year, accounting for 63.9% and a little more than that of 2001. Because farming activities were frequent in the reservoir area and there were several harvests in one year, slope farmland was still the main factor causing water and soil erosion.

Monitoring results of the fixed soil monitoring stations of 44 representative paddy fields and arid fields showed that soil contents of nitrogen, phosphorus and potassium were basically the same as those of 2001 and contents of heavy metals were within the background value and attained the first level standard of the soil environmental quality.

3.6.2 Investigation on the influence of orange belts

In 2002, the results monitoring and investigation on the 194 towns and villages in the 19 counties in the reservoir area showed that: orange production in the reservoir area was normal; orange quality did not have qualitative change and no abnormality was discovered by soil examination of the orange belts.

The orange cultivation area in the reservoir area was 27,514 hectare, a little more than that of 2001. Total yield was 268,900 tons, remaining the same as that of 2001. Yield per mu was 651.8 kg, a little less than that of 2001. Investigation on yield proportion of oranges of different qualities showed that the first level, second level and third level oranges accounted for 42.6%, 39.6% and 17.8% respectively. Compared with that of 2001, the proportion of the first level oranges dropped by 7.3 percentage points and proportions of the second and third level oranges rose by 5.1% and 2.1% respectively.

Monitoring results of orange quality in the reservoir area showed that moisture content of oranges ranged from 83.5% to 88.5% with an average of 85.7%; vitamin C content ranged from 163.5 mg/100g to 425.4 mg/100g orange with an average of 245.5mg/100 g orange; and sugar content ranged from 6.5% to 12.6% with an

average of 9.3%. Results of examination on pesticide residues in oranges showed that the content of parathion methyl was 0-0.005mg/kg and less than 0.005mg/kg in all oranges and methamidophos was not found. The pesticide residue indicators met the food hygiene standard.

For the soil in the orange belts, the contents of total nitrogen, total phosphorus, total potassium, alkali dissolved nitrogen, quick-acting phosphorus and quick-acting potassium didn't change much. The contents of heavy metals were with the background value and attained the first level standard of the soil environmental quality.

3.6.3 Rural energy

The results monitoring and investigation on 192 villages and towns in the 19 counties of the reservoir area in 2002 showed that: the energy in the rural areas still mainly depended on the direct combustion of straw; the proportion of small hydropower rose; the area of fuel wood forests decreased; the proportion of biogas-the biological energy rose greatly, but still very small in the rural energy structure. The proportion of straw combustion, small coal kilns, small hydropower, fuel wood and biogas was 37.3%, 27.3%, 18.4%, 13.3% and 3.7% respectively. Among these, the proportion of biogas rose by 1.05 percentage points than that of 2001.

Investigation on the number of biogas pools and biogas production amount in the rural areas showed that in the 1.0864 million rural families in the reservoir area, there were 51,740 biogas pools with an annual production of 18.7037 million m³. Due to large-scale spreading of biogas bonded ecological homestead construction and high-efficiency eco-agricultural construction in the reservoir area, there were 4.76 biogas pools per hundred families, with biogas production of 17.22 m³ per family in the whole year, rising by 70.6% and 77.3% respectively compared with that in 2001. However, biological energy accounted for only 3.7% of total energies needed, far from meeting the energy demand of the rural area.

The area of fire wood forest in the reservoir was 41,474 hectare, 0.038 hectare per family. Fuel wood production amount was 2.9284 tons, 2.69 tons per family. Compared with that of 2001, the area of fire wood forest decreased by 10,187 hectare, the average area of fire wood forest per family dropped by 17.4% and the average fire wood amount per family rose by 0.15 tons.

3.6.4 Insect pests of crops

In 2002, the results monitoring and investigation on 192 towns and villages in the 19 counties in the reservoir area and the key monitoring and forecasting stations of Yunyang, Kai County, Zhong County and Zigui showed that: the area affected by insect pests decreased significantly, control rate rose and no explosion and major harm of certain insect pest took place. The extent of insect pest of crops in the reservoir area was medium. Total area affected by insect pests was 483,167 hectare·times, 19.0% less than that of 2001. Area controlled was 326,293 hectare·times, 26.6% less than that of 2001; control rate was 77.9%, 3.3% higher than that of 2001; grain loss recovered was 110,444.4 tons and actual loss was 39,728.6 tons. The base number of the snout moth's lava over the winter in the rice paddy fields in the reservoir area was 1542 per hectare.

Table 3-2 Statistics of Main Crop Insects Pest in the Three Gorges Reservoir Area in 2002

Type of Insects Pest	Area Affected	Area Controlled	Losses	Actual	Extent of Pest
	(Hectare·times)	(Hectare·times)	Recovered (t)	Losses (t)
Rice blast	21026.67	29680	13561.1	2236.87	Medium to light
Sheath and culm blight of rice	33166.67	26386.67	5470.89	1175.91	Medium to light
Wheat ibberellic Disease	19246.67	12713.33	2418.3	2599.46	Light
Potato late disease	26093.33	24933.33	13548.76	2218.87	Medium to light
Rice paddy bores	83460	94513.33	12098.89	3767.56	Medium to serious
Rice flying flea	31980	41366.67	20498.72	1598.16	Medium
Orange red and yellow spiders	41326.67	45273.33	12846.59	2946.52	Medium
Rats	226866.67	101426.67	30001.16	23185.21	Medium

3.7 Geological Disasters

3.7.1 Earthquakes

In 2002, there were 61 times of ML≥2.0 earthquakes occurred in the Three Gorges reservoir area and surrounding areas (28°-34°north latitude and 108°-114°east longitude), among which there were 4 times of ML≥3.0 earthquakes. The highest level earthquakes (ML＝3.7) happened in Xiaoji, Xiangyang District of Xiangfan City at 19:08 on March 18, 2002. Earthquake intensity was weaker than that of 2001. Earthquakes mainly concentrated in Yuan'an, Zhongxiang, and areas near Zigui, Geheyan reservoir area of Qingjiang, Wushan County and Shizhu County of Chongqing. Geheyan reservoir area was subject to relatively high frequency of earthquakes and other places experienced lower earthquake frequency. Analysis results on earthquake activities and premonitoring materials showed that earthquake activities in this area in 2002 were basically at a normal level.

Table 3-3 Earthquake frequency in the Three Gorges Reservoir Area and Surrounding Area in 2002

3.7.2 Landslips, collapses and mud-rock flows

● Basic situation

In 2002, in the scope of the Three Gorges reservoir area, there were 199 places experiencing new landslips and collapses in counties (districts) including Yiling, Zigui, Xingshan and Badong, etc. in Hubei Province，and there were over 4100 places known undergoing old and new landslips and collapses in counties (districts) of Wushan, Fengjie, Yunyang, Wanzhou, Kaixian, Zhongxian, Shizhu, Fengdu, Fuling, Wulong, Changshou, Banan, Jiangjin and the main urban area Chongqing Municipality (including Yuzhong District, Yubei District, Shapingba District, Jiulongpo District, Dadukou District, Beibei District, Nan'an District and Jiangbei District). Monitoring and early warning and monitoring and prevention by the public were carried out by the land resources agencies of all counties (districts). Therefore, the large numbers of landslips and collapses only caused certain economic losses. People all safely removed and evacuated.

● Monitoring and early warning

In March 2002, monitoring and early warning program on geological disasters in the Three Gorges reservoir area was launched in an all round way. After that, field surveys, location design and construction were carried out for professional monitoring. Public monitoring and prevention was organized by land resources agencies in counties (districts), towns and villages. Monitoring and early warning made preliminary achievements.

In 2002, landslips, collapses and mud-rock flows in 38 places were successfully forecasted. Residents were evacuated in time. Over 1000 people were free from hurt and death.

● Fully implementation of the geological disasters control program in the reservoir area

In 2002, member agencies of the Leading Group for Geological Disasters Control in the Three Georges Reservoir Area further strengthened guidance, coordination, supervision and examination according to requirements of the central Communist Party and deploy of the State Council and fully implemented the Overall Programming on Geological Disasters Control in the Three Gorges Reservoir Area approved by the State Council. Geological disasters control of the reservoir area sped up continuously and went on smoothly on the whole, which laid the foundation for task completion on schedule.

By December 31, 2002, among the 197 proposed collapse and landslip control projects in Hubei Province and Chongqing Municipality (plus Youxia and Shixia sections of Xingzi Road), 195 were started or changed to other treatment measures, accounting to 99.0% of the total in programming.  Among the 81 bank collapse control projects in programming, 73 were started, accounting for 90.1%  of the total. Steep slope adjustment projects in 195 places were started and those in 152 places were completed. A total of 1.09437 billion yuan was invested in the control projects.

In order to guarantee safety of the reservoir area after water stored in the 135 m high dam (section up the dam) of the Three Gorges Project, the first group of geological disasters control projects have been brought in tight implementation. The first stage geological disasters control projects will be completed before water stored to the 135 m level in section up the dam in June 2003.