3. Results
3.1. Spatial and Temporal Trends in Crops Production Pattern in the area
As shown in Table 2, the spatial and temporal patterns in the area's crop production pattern are shown based on three classes, with the main emphasis on identifying the rice crop's condition. When the time series is explored in the google earth engine, the rice crop was indicated in increasing trends whereas dense vegetation, water, and other small vegetation are showing in a decreasing trend based on the calculated results of the NDVI of rice crop, vegetation, water, and others in the year 2000, 2009 and 2018 (Fig. 2 and Table 2). The graph also clearly indicated the increasing and decreasing trends of classes. The negative slope expresses the decreasing trend while the positive slope indicates the increasing trend.
Table 2
class type
|
2000
|
2009
|
2018
|
dense vegetation
|
0.269
|
0.012
|
0.080
|
Rice
|
111.266
|
134.69
|
135.23
|
water and others
|
0.333
|
0.356
|
0.283
|
Furthermore, as it is shown in Fig. 3a, the NDVI values in 2000 for dense vegetation, rice, and water, and others are 2691.22 ha, 11126.6ha, and 3328.02 ha respectively. In Fig. 3b, the NDVI value in 2009 for dense vegetation is 120.06 ha, for rice 13469.4 ha, and water and others are 3556.36 ha. Moreover, in 2018 as it is indicated Table 2 and shown in Fig. 3c, the value for dense vegetation, rice and water, and others are 796.086 ha, 13523.4 ha, and 2826.27 ha respectively. Based on these calculated data, the figures clearly showed that there is an increase in the area coverage for rice while dense vegetation and water and others are showing a decline. The spatial and temporal patterns of rice crop production have increased by 2396.8 ha whereas water and others are decreased by -1895.134 ha and − 501.75 ha in the year 2000 to 2018, respectively.
Accordingly, it is indicated in Table 3, the sampled respondent mentioned that the size of their farmland before the introduction of rice was 159.75 ha but after the introduction of rice this number flipped to 284.75 ha. The difference is 125 ha.
Table 3
Expansion of farmland for rice production
Sample Kebeles
|
No of sample Respondents
|
Their farmland
|
|
Size of their farmland in Timad
|
|
|
1 timad = 0.25 ha
|
|
Yes
|
No
|
Before rice
|
%
|
After rice
|
%
|
Increased
|
%
|
Kidest Hana
|
69
|
68
|
1
|
124
|
19.5
|
221
|
19.4
|
97
|
19.3
|
Shina
|
81
|
81
|
0
|
130
|
20.5
|
234
|
20.5
|
104
|
20.6
|
Shaga
|
57
|
57
|
0
|
95
|
15
|
175
|
15.4
|
80
|
15.9
|
Wagetera
|
91
|
91
|
0
|
146
|
23
|
261
|
22.9
|
115
|
22.8
|
Nabega
|
87
|
87
|
0
|
140
|
22
|
248
|
21.8
|
108
|
21.4
|
Gross cropped area
|
385
|
384
|
1
|
635
|
100
|
1139
|
100
|
504
|
100
|
Table 4 showed that about 88% of sampled respondent farmers responded they do have sufficient farmland to produce more rice crops to satisfy their family’s needs and for sale. On the other hand, about 12% of the respondents said that they have sufficient farmland to produce rice only to satisfy their family needs.
Table 4
No of Kebeles
|
A farmland sufficiency to produce food for your families
|
No of respondent
|
Yes
|
No
|
Kidest Hana
|
69
|
62
|
7
|
Shina
|
81
|
71
|
9
|
Shaga
|
57
|
52
|
5
|
Wagtera
|
91
|
77
|
14
|
Nabega
|
87
|
75
|
12
|
Respondents were asked about their previous production style before the introduction of rice and they reported that they produced different crops in the study areas. These were Teff (Eragrostis tef), maize (Zea mays L.), noug (Guizotia abyssinica), finger millet (Eleusine coracana), chickpea (Cicerarietinum), lentil (Lens culinaris), grass pea (Lathyrus sativus), green pepper (Capsicum spp.) and Barely (Hordeum Vulgare) in small amount and animal rearing at a large extent. The respondents were explained that these crops were also produced far away from the wetlands in the study site.
This time most of the respondents have been engaged in rice production during the summer season while in the winter season, they started to produce horticultural crops of vegetables like an onion (Allium cepa), garlic (Allium sativum), and tomatoes (Solanum Lycopersicum). They are grown under small-scale irrigation.
Cultivated area and crop yield produced for the year 2014 and 2015 cropping season
Regarding the area cultivated for the wetlands of Fogera floodplain, the two years data showed that cultivated area coverage of the rice crop was 245.25 ha and 284.75 ha in the year 2014 and 2015, respectively (Table 5). It is also mapped that in Fig. 4, the land-use coverage for rice and other land use for the year 2013, 2015, and 2016, the result revealed the coverage for rice has shown increment.
Table 5
The area cultivated and crop yield produced for the year 2014 and 2015
Rice
|
Name of sample kebele
|
No of sample respondent
|
2014
|
2015
|
Cultivated land in Timad= (0.25 ha)
|
Total cultivated land in ha
|
Farmland per sample house hold
|
Cultivated land in Timad= (0.25 ha)
|
Total cultivated land in ha
|
Farmland per sample house hold
|
Increment in ha
|
Kidest Hana
|
69
|
184
|
46
|
0.66
|
221
|
55.25
|
0.8
|
9.25
|
Shaga
|
81
|
208
|
52
|
0.64
|
234
|
58.5
|
0.72
|
6.5
|
Shina
|
57
|
144
|
36
|
0.63
|
175
|
43.75
|
0.77
|
7.75
|
Wagetera
|
91
|
225
|
56.25
|
0.62
|
261
|
65.25
|
0.72
|
9
|
Nabega
|
87
|
220
|
55
|
0.63
|
248
|
62
|
0.71
|
7
|
Practice on cropping pattern
About 89% of the sampled household respondents reported that the types of cropping pattern practiced are mono-cropping whereas about 11% of sampled respondents said that they practiced crop rotation (Table 6). The later respondents who pracice crop rotation explained their reason why they practiced it? This is because their farmland is far away from the floodplain which is located on the upland side of the Fogera floodplain.
Table 6
Types of cropping pattern
type of cropping pattern do you practice
|
No of kebeles
|
No sample respondents
|
Mono cropping
|
Crop rotation
|
Intercropping
|
Other
|
Kidest Hana
|
69
|
62
|
7
|
0
|
0
|
Shaga
|
81
|
69
|
12
|
0
|
0
|
Shina
|
57
|
51
|
6
|
0
|
0
|
Wagetera
|
91
|
81
|
9
|
0
|
0
|
Nabega
|
87
|
79
|
8
|
0
|
0
|
Past and present use of inputs to produce rice and other crops
The respondent farmers were asked about the methods to maximize yield. The entire respondent responded that the methods to maximize yield are applying artificial inputs such as fertilizer, improved seed, insecticide, and herbicide (Table 7). Furthermore, the other methods are the expansion of rice farming through encroaching wetlands and communal grazing lands. Most of the sampled household farmers said that application of insecticide has been used for most crops of chickpea (Cicer arietinum) and grass pea (Lathyrus sativus) sowed after the harvest of rice (Oryza sativa) crop. The sampled respondents were asked regarding the inputs used for other crops in the previous time. They reported that all respondents were not used artificial input rather they used manure for the production of maize (Zea mays L.) and green pepper (Capsicum spp.). Besides, a fallowing system without any inputs was used. As it is reported in the FGD and interview, the main reasons were the population was very small in number, rice and other artificial inputs were not introduced and adapted. It is also explained in the discussion, in previous times their farmlands were better fertile than the current one. Besides, it is reported by sampled household the cause for the reduction of yield in the study area was the reduction of soil fertility and upland erosion that brought sand and other unfertile soil particles like gravel, which reduce the amount of water in the wetland of study area. Hence, in the study area, it has been started to use artificial input for their farmland to yield.
Table 7
Inputs used for the production of crops
If there is an increase in production, what are the causes
|
No of kebeles
|
No of respondents
|
Fertilizers
|
manure
|
improved seed
|
fallowing
|
Crop rotation
|
using insecticides
|
using herbicides
|
Kidest Hana
|
69
|
69
|
0
|
69
|
0
|
0
|
69
|
69
|
Shaga
|
81
|
81
|
0
|
81
|
0
|
0
|
81
|
81
|
Shina
|
57
|
57
|
0
|
57
|
0
|
0
|
57
|
57
|
Wagetera
|
91
|
91
|
0
|
91
|
0
|
0
|
91
|
91
|
Nabega
|
87
|
87
|
0
|
87
|
0
|
0
|
87
|
87
|
3.2. Artificial Inputs Used
According to Fig. 5, about 45.5% of respondents already started to apply fertilizer, 23% of the respondents started to use improved seed and 77% of sampled households still use local seed. About 95% of the sampled household respondents said that they used pesticides when pests occurred in their area (eg. See photo showed in Fig. 6). This spraying of pesticides could kill insects and those insects would be eaten by birds. So, the birds could be affected. Herbicides are used to control weeds in their farmland by about 64% of the respondents.
3.2.1 Benefits recognized from using artificial inputs
Figure 6 Spraying of pesticide in the wetland areas
As Table 8 showed, almost 100% of sampled household respondents responded that the benefits recognized from using artificial inputs were increased yield of rice. They also said that the amount of hays getting after trashed of the crops for livestock feed was very good.
Table 8
Recognition the importance of inputs use
benefits did you recognize from using artificial inputs
|
No of kebeles
|
No sample respondents
|
Increase yield
|
decreasing yield
|
No change
|
Kidest Hana
|
69
|
68
|
0
|
0
|
Shaga
|
81
|
81
|
0
|
0
|
Shina
|
57
|
57
|
0
|
0
|
Wagetera
|
91
|
91
|
0
|
0
|
Nabega
|
87
|
87
|
0
|
0
|
Recognition of the negative impacts of artificial inputs used
As Table 9 showed that about (74.3%) household respondents reported artificial inputs has brought water pollution (from their physical observation point of view), while about (72.5%), (96.1%), (73.2%) and (72.7%) reported that there was a reduction of the number of birds, bee's colony, fish availability in the wetlands and the Lake Tana, and other insects like reptiles, amphibians in the wetlands of the study area.
Table 9
Negative Impacts of Artificial Input Used
No of kebeles
|
No sample respondents
|
Do you recognize the negative impacts from using artificial inputs
|
Water pollution
|
Reduction of birds
|
Reduction of bees
|
Reduction of fish
|
Reduction of
other insects
|
Kidest Hana
|
69
|
53
|
47
|
55
|
50
|
48
|
Shaga
|
81
|
64
|
63
|
80
|
63
|
63
|
Shina
|
57
|
41
|
41
|
57
|
41
|
41
|
Wagetera
|
91
|
66
|
66
|
91
|
66
|
66
|
Nabega
|
87
|
62
|
62
|
87
|
62
|
62
|
Recession farming
As indicated in Table 10, about 22% of the sampled household respondent farmers said that they practice recession farming. That means when the water of wetland and Lake retreated (Fig. 7). This 22% of respondents also explained their experience in producing maize in the surrounding wetlands and Lake Tana when the amount of water retreats in the dry season after harvesting their rice crop. Whereas, about 78% of the sampled households were not using recession farming because their farm areas are not close to the wetlands and Lake Tana.
Table 10
No of sample kebeles
|
|
Do you produce crops in the form of recession farming
|
No of sample respondents
|
Yes
|
No
|
Kidest Hana
|
69
|
11
|
58
|
Shaga
|
81
|
16
|
65
|
Shina
|
57
|
8
|
49
|
Wagetera
|
91
|
25
|
66
|
Nabega
|
87
|
23
|
64
|
Impacts of recession farming
Respondents were also asked about the impacts of recession farming on wetland and Lake resources. According to their physical observation, 100% of respondents said that the wetland and Lake resources are reduced through time because of recession farming activities in the study area, especially papyrus, grass, birds, amount of water, the color of water, increase siltation, turbidity of the water, etc. Hence, farmers were trying to maximize their productivity through the expansion of recession farming at the expense of wetlands and Lake Tana in the study area.
The respondent farmers interviewed and FGD participants were also asked for triangulation about what changes have been observed in wetlands and water resources in their kebele. According to their response in physical observation, their explanations summarized that there was a reduction of water level in the wetland, fish, loss of papyrus and other different grass species, drying of wetland, hippopotamus in number, birds, different insects in the wetlands, etc.
The resources of wetlands reduced over time has been ranked by respondents, As Table 11 illustrated below, respondent farmers were asked to respond regarding the natural resource reduction around the wetland of Fogera. The questionnaire has different multiple choices such as the situation of the following resources like papyrus, fish, sand, birds, grass, amount of water, and hippopotamus. According to their observation, the respondent farmers tried to put the reduction of wetland resources in order of rank (Table 11). Based on the respondents' choice summary, the whole sampled respondents (385) said that papyrus has reduced first and the others, such as fish, grass, amount of water, birds, hippocampus and sand reduction have been presented 2nd, 3rd, 4th, 5th, 6th and 7th ranked respectively (Table 11). These weighted ranks indicated us papyrus is the first highly reduced resource and sand is the least reduced resource.
Table 11
Rank of wetland and Lake Tana resources
Description of wetland resources
|
Resource
Rank
|
Papyrus
|
Fish
|
Sand
|
Birds
|
Grass
|
Amount of water
|
Hippopotamus
|
Wetland resources highly reduced is ranked from the smallest number 1 to the large number 7. eg, if 1 is selected, the resource is highly reduced.
|
First = 1
|
385
|
0
|
0
|
0
|
0
|
0
|
0
|
Second = 2
|
0
|
135
|
5
|
7
|
191
|
47
|
0
|
Third = 3
|
0
|
43
|
63
|
10
|
95
|
171
|
3
|
Fourth = 4
|
0
|
178
|
4
|
117
|
14
|
60
|
12
|
Fifth = 5
|
0
|
27
|
30
|
189
|
15
|
71
|
53
|
Sixth = 6
|
0
|
1
|
38
|
32
|
28
|
13
|
273
|
Seventh = 7
|
0
|
1
|
245
|
30
|
42
|
23
|
44
|
In this table, the data is the weighted value for each resource responded by sampled respondents. eg, 385 sampled respondents give rank for each resource.
|
Resource
Rank
|
Papyrus
|
Fish
|
Sand
|
Birds
|
Grass
|
Amount of water
|
Hippopotamus
|
1
|
385
|
0
|
0
|
0
|
0
|
0
|
0
|
2
|
0
|
270
|
10
|
14
|
382
|
94
|
0
|
3
|
0
|
129
|
189
|
30
|
285
|
513
|
9
|
4
|
0
|
712
|
16
|
468
|
56
|
240
|
48
|
5
|
0
|
135
|
150
|
945
|
75
|
355
|
265
|
Rank value *each value given by respondents eg, 1*385 = 385 continuous like this
|
6
|
0
|
6
|
228
|
192
|
168
|
78
|
1638
|
7
|
0
|
7
|
1715
|
210
|
294
|
161
|
308
|
Weighted Sum Total
|
|
385
|
1259
|
2308
|
1859
|
1260
|
1441
|
2268
|
|
Rank
|
1st
|
2nd
|
7th
|
5th
|
3rd
|
4th
|
6th
|
Wetland conservation issues of Fogera
Sampled household respondents were asked to answer regarding the wetland conservation issues. About 100% of sampled household respondents responded that they strongly want to conserve the wetlands of Fogera in the study area and the surrounding of Lake Tana. They reported that the benefits of the conservation of wetland of Fogera can save the resources mentioned such as papyrus, fish, birds, grass, getting pure water, moderate climate, reduction of flooding, increasing soil fertility, high amount of water, increase vegetation, Provide hatchery and nursery areas for the fish, erosion control, nutrient retention, groundwater recharge, recreational activities, Habitat for hundreds of species of animals and birds, the first line of defense against pollution from surface water runoff, increasing different insects like bees, etc. Generally, the biodiversity of the wetlands would increase. From these resources, the local people can wisely extract and use the previous style of the community.
The respondents also explained the demerit of conservation of wetlands, the whole respondents said that even though the merits of the conservation of the wetland and the Lake resources have been better, there was also the demerits of conservation of wetland summarized as the following: no use of wetlands as they want especially illegal expansion of rice agriculture to the wetlands. Recession farming is considered as a disadvantage for certain users of recession farming because they said that increasing the number of hippopotamus and birds could damage their crops, there would no freely fish harvest in the wetlands and the Lake (Fig. 8), there would not be free grazing that some of the people consider as a demerit.
The sampled household farmers, interviewed respondents and FGD participants were asked regarding the practice that was implemented in their floodplain in the study kebeles before the introduction of rice, their explanation was summarized as follows: most of the floodplain was used for grazing purpose for Fogera known indigenous cattle breed, the wetland areas were covered by papyrus vegetation, which was used for different purpose such as for roof thatching, for making of the mat, for the home fence, for making traditional fishing traps for fishing locally and boat making for local transportation, use of leaf of papyrus during the ceremony, Grass for roof thatching, Fishing site, some types of crops like noug, Green pepper, and finger millet, "Senele" (Butia Capitata) used for making a mat, raincoat, hut used as a cover for the dead person during his time of burial, Reeds used for making rope, brooms (Cleaning materials used a brush indicated in the left) (Fig. 9).
The sampled respondent household farmers were asked regarding their observation whether there was a significant land-use change observed in wetland areas. The entire sampled respondent household farmers were responded that yes, there was a significant land-use change in the study sample kebeles. The interviewed farmers and FGD participants have also supported their ideas.
The main reasons explained for the change observed were scarcity of agricultural land especially the introduction of rice crop encouraged the local people looking for additional farmlands to produce more rice, population growth, the tragedy of the commons (the wetland areas and the borders of Lake Tana were common resources that everyone can access with no controlling mechanism) and expansion of recession farming around the wetland areas, grazing lands, and Lake Tana to produce maize, tomato, onion, teff, etc. Therefore, according to their explanation, most of the wetland, grazing land, and forest land changed into agricultural land-use systems. These ideas have been substantiated by land use land cover change detection through Landsat image classification of 1973 and 2014 that showed most of the different land-use systems changed and incorporated into agricultural land-use systems.
Sampled household farmers were also asked regarding the effects of land-use changes to the wetland and Lake Tana resources to say yes or no. The whole sampled household farmer respondents said yes and this changing of the land-use system has brought the reduction of wetland and lake resources. The reduction of those wetland and lake resources has brought the consequences of negative impacts on the wetlands and Lake Tana. The negative impacts explained not only by the sampled household respondents but also by the interviewed and FGD participants explained that the seasonal overflow water, reduction of the number of resources like birds (loss of recreation and aesthetic situation of the area), loss of papyrus vegetation, the turbidity of the wetland and Lake water (physical color change observed), siltation problem and loss of reeds has been observed in the study site according to their explanation. These problems have been increasing over time in the study site.
3.4. Discussion
Spatial and Temporal Trends in Crops Production Pattern
Based on the measured results of the NDVI of rice crop, vegetation, water, and others (like small grasses) in the years 2000, 2009, and 2018, the rice crop showed a growing trend while dense vegetation, water, and others (like small grasses) showed a decreasing trend. Rice crop production has increased by 2396.8 ha in both space and time, while water and other resources have decreased by -189 ha. This is supported by the fact that wetlands are characterized by extensive and intensive cultivation, which includes more land for rice production (Gebrekidan 2014). Furthermore, people in the study area tend to grow rice over other crops because of its high yield existence and high market price relative to other food crops (Gebey 2012).
The area cultivated and crop yield produced for the year 2014 and 2015 cropping season
The results showed that for the cropping seasons of 2014 and 2015, the area cultivated and crop yield produced increased. Furthermore, the land-use coverage for rice and other land uses via the map for the years 2013, 2015, and 2016 substantiates this notion (Fig. 5). According to IPMS (2005), the rice production area had increased, and farmers in seasonally flooded areas wanted to increase their rice acreage and production because the price of rice had tripled, further stimulating interest in rice production.
Practice on cropping pattern
Mono cropping is the most common cropping pattern recorded by the majority of household respondents in the study wetland areas. This result is consistent with the findings of (Tilahun et al., 2012). We found that the introduction of rice has changed the production system, especially in the wetlands of the Fogera floodplain, from livestock-dominated to rice-dominated over the last century.
Past and present use of inputs
Before the introduction of rice, both respondents said they used manure instead of artificial input to grow maize (Zea mays L.) and green pepper (Capsicum spp.). According to the FGD and interview session, the key factors were that artificial inputs were unknown and the soil was extremely fertile. Previously, no organic fertilizer was used by farmers (Tegegne and Mathias 2019). Currently, he explained that all farmers apply nitrogen-based fertilizer and up to 65% of the farmers apply phosphorus-based fertilizer. Fertilizer is applied to the rice field at different stages of growth either two or three times depending on the availability of fertilizer in the district. They use both DAP and UREA (Tegegne and Mathias 2019). Their farmlands were more fertile in the past than they are now, according to FGD participants. Furthermore, soil fertility depletion and upland erosion added sand and other unfertile soil particles, such as gravel, to the study area's wetland, decreasing the amount of water in the wetland. As a result, farmers in the study region have begun to use artificial inputs (fertilizer, improved crop, insecticide, and herbicide) on their farmland to increase productivity. They use DAP as well as UREA (Tegegne and Mathias 2019). As a result, the biodiversity of the Fogera floodplain wetlands has decreased. For example, before the use of artificial fertilizers, moist grasslands and herbaceous fens in Europe were used for grazing and hay-making. Rice has historically been grown in heavily transformed environments with rice paddies and a human-controlled water regime in other parts of the world. Rice cultivation allowed for a landscape rich in diversity, particularly in macroinvertebrates, fish, and waterfowl, until the early twentieth century (Kawano 2000; Shimoda 2007). However, as a result of the intensification of agricultural practices associated with the ‘green revolution in the second half of the twentieth century, fertilizer and pesticide use has skyrocketed, resulting in a drastic rise in pesticide and fertilizer use. Summarizing, intensive agricultural use of wetlands has changed their ecological character significantly, as crop growth and livestock raising necessitate reclamation initiatives. Biodiversity has also been significantly impacted in such wetland areas, and significant portions can no longer qualify as wetlands. However, since low-intensity cultivation occurs in wetlands, requiring a regime of extensive use without fertilizers or pesticides, the landscape diversity of the wetland environment can be high, although the species composition and setting vary significantly from that of its natural state. Many of the species have been destroyed out by the agricultural intensification of the twentieth century, which included the use of fertilizers and pesticides (Millennium Ecosystem Assessment 2005).
Artificial Inputs Used
Farmers have already begun to use artificial inputs such as fertilizer, improved crop, pesticides, and herbicides, according to the sampled respondents. This is supported by the findings of (IPMS 2005), which found that improving agronomic practices increased rice yields (weed control, use of fertilizers and pest and disease control). Farmers reported increased use of modern agricultural technologies such as higher-quality seed of preferred varieties, agro-chemicals (chemical fertilizer, herbicides, and pesticides), and irrigation technologies (water wells and water pumps) among other items. As a result, yields per unit of land and labor have risen. However, there have been reports that increased production is reducing soil fertility, forcing many farmers to increase their use of urea and other chemical fertilizers in order to sustain their yields.
According to a survey, no fertilizer has been applied to rice production in the district so far. Farmers, on the other hand, have started applying fertilizer in recent years as yields on their plots have declined (Hagos et al., 2014). Despite the fact that no fertilizer was used ten years ago, all farmers now use fertilizer, according to this report. Disease and pest infestation have reduced yield production, necessitating a significant change in fertilizer application. Fertilizer problems such as cost and availability are a source of dissatisfaction for farmers (Tegegne and Mathias 2012).
Benefits recognized from using artificial inputs
Artificial inputs, according to respondents, resulted in higher rice crop yields. Besides, the hay provided after the rice crops were trashed was suitable for livestock feed. According to some evidence, chemically-based agriculture produces higher yields per area than "organic" traditional practices. However, this comes at a cost: high costs due to chemical and fuel inputs (Pimentel 2005), as well as numerous environmental effects that can be detrimental in the long run (Pimentelh 1996).
Recognition of the negative impacts of artificial inputs used
Artificial inputs, according to the respondents' observation point of view, have resulted in water contamination, a decrease in the number of birds, bee colonies, fish availability in the wetlands and Lake Tana, and other insects such as reptiles and amphibians in the study area's wetlands. Crop yields have increased as a result of the Green Revolution's major improvements in rice cultivation, but rice cultivation has become less sustainable as a result of eutrophication, fish kills caused by pesticide toxic effects, and biodiversity loss (Bambaradeniya, 2003). Rice field ecosystems rich in biodiversity exist in almost all rice-growing regions, according to Shimoda (2007), especially in areas where rice-growing intensification is impractical or impossible. Traditional rice systems were sufficiently multifaceted ecosystems that did not involve the use of chemical fertilizers and maintained a moderate but stable yield for thousands of years because a diverse array of microorganisms and other invertebrates allowed them to maintain soil fertility by recycling nutrients for rice cultivation, in contrast to modern rice cultivation (Moorman and Breeman, 1978; Roger et al., 1991). Despite being flooded during the growing season, rice fields do not provide wetland habitat for wildlife or macroinvertebrates, as well as many other wetland ecosystem services including carbon sequestration and biodiversity protection (Stenert et al., 2009).
Recession farming
In the dry season of the year, farmers grow crops in the form of recession farming around wetlands and Lake Tana areas, as explained by 22% of the sampled household respondents. According to Sander (2011), recession farming is used in Ethiopia when the area gets flooded due to its past. Different types of crops are planted, planting techniques are used, and the combination of other flood-related sources of income (fishery, for example) and strategies for coping with the risks are used differently across Ethiopia. The major regions where flood recession agriculture is considered to be practiced are Lake Tana, Baro-Akoba, Omo Valley, Wabi Shebelle, and Upper Awash. During the dry season, there are also a few small wetland areas where vegetables and other crops are grown on the drier parts. In the north of Ethiopia, flood-based farming is practiced along the shores of Lake Tana and along some of the tributaries that feed the lake. The Fogera floodplain, east of Lake Tana, revealed that the flood-prone area subject to flood recession farming year to year. The key anthropogenic problems are recession agriculture, unplanned urbanization, rapid population growth, indiscriminate manufacturing and construction activities, disposal of domestic and industrial hazardous wastes, and free grazing. Many people in the lake subbasin already consider wetlands to be unsafe breeding grounds for disease vectors. The ecological and socio-economic values of activities near Lake Wetland destruction and conversion for recession are seldom considered. Agriculture continues to be considered a technologically advanced mode of development (Ibrahim and Minwyelet 2018)
Impacts of recession farming
The effects of recession farming on wetland and lake resources have been demonstrated, with papyrus, grass, birds, amount of water, the color of water, increased siltation, turbidity of the water, and other resources being decreased over time. According to the interviewed and FGD participants, there was a decline in water level in the wetland, fish, depletion of papyrus and other grass species, drying of the wetland, hippopotamus population, birds, and other wetlands issues. Recession farming has had a detrimental effect on the fauna, flora, and hydrology of the study site. New lands were developed at the land/swamp interface as a result of the recession and the draining of wetlands, resulting in major destruction of the wetland environment. Several studies have found a gradual shift in farming system enterprises from terrestrial to wetland-based development by households close to wetlands (Kairu 2001; Kipkemboi 2006). Aside from better land-use practices, other anthropogenic activities that have become more severe include livestock overgrazing and macrophyte overharvesting, both of which play a synergistic role in setting inertia of deterioration likely to disrupt the area's hydrological cycle and microclimate regulation. As wetland macrophyte vegetation disintegrates due to over-exploitation and loss of wetland vegetation, pollutants and nutrients are transported directly into the lake (Odada et al., 2004; Raburu and Okeyo-Owuor 2005).
The euphotic zone in littoral areas lakes shallows due to increased turbidity caused by the destruction of the buffer zone, suggesting a drastic drop in water quality. This had a significant negative impact on the attractiveness of the local tourism-based economy (Ayalew 2010).
Wetland conservation issues of Fogera
Wetland conservation is very important to the people who live in the Fogera wetlands and the surrounding region of Lake Tana. They said that conserving the Fogera wetland would save resources such as papyrus, fish, birds, and grass, as well as providing clean water, a moderate climate, reduced flooding, increased soil fertility, a large amount of water, increased biodiversity, fish hatcheries, and nursery areas, erosion control, nitrogen retention, groundwater recharge, and recreational activities, habitat for hundreds of species of animals and birds, the first line of defense against pollution from surface water runoff, increasing different insects like bees, etc. Rice paddies, coastal grazing marshes, recession agriculture and aquaculture in large floodplains, and cropping of small seasonal wetlands are examples of wetlands that provide food and other agricultural products http://www.ramsar.org/sites/default/files/wwd14_leaflet_en.pdf. Rice (Oryza sativa) habitats are important for the survival of certain waterfowl species. Traditional wetland rice farming has proven to be highly competitive in terms of yield sustainability and wetlands fauna and flora preservation. Moderate but steady yields have been sustained for thousands of years with no negative effects on the climate.
Hydrological Alteration
Seasonal and annual variations in the hydrological functions of the study wetlands were observed. The study of wetland water flow and rainfall patterns are both similar. In the study region, there is a strong association between water flow and rainfall (r = .868**, N = 35 at P < .000). In river ecosystems, hydrological regimes create biotic diversity, and hydrological variation is recognized as a primary driving force (Taylor et al., 2003). When humans alter the flow regime, the normal cycle of hydrologic variation and ecosystem dynamics is disturbed (Dunne and Leopold 1978; Poff et al., 1997).