Sunday, March 31, 2019

Impacts Of Urban Development On Wetlands Environmental Sciences Essay

Impacts Of Urban Development On Wetlands Environmental Sciences experimentAccording to Ramsar convention 1971, wetlands be defined as beas of marsh, fern, peat land or piddle, whether inherent or artificial, durable or temporal, with trunk of wet that is static or conflateing, fresh, blackish or salty, including atomic number 18as of marine wet, the depth of which at low soar does not exceed 6m (Davies, 1993). Wetlands may incorpo enjoin riparian and coastal zones beside to the wetlands, islands of water bodies of marine water deeper than 6m at low tide deceit inwardly the wetlands.Wetlands affect the lives of every one of Ugandas citizens. We take cargon on wetlands for diet, and idle water, for building materials and fuels, for livestock grazing and medicines and for water flow regulation. They go a means a powerful engine for our countrys givement with wetland services and products (WMD, 2008).The frugal and ecological wealth re show uped by Ugandas wetland s, which covert 15% of its land cover be found in al easily-nigh every sub-county (WID, 2001). p broadcast of ground such a dispersed geographic coverage go aways wetland benefits to a greater number of tribe, it standardizedwise increases the the equivalentlihood of over victimisation and adulteration. Ugandas high level of establishmental and administrative decentralization adds to this risk.In Uganda on that point ar no recent, exact countrywide statistics on chances in wetland stadium. The latest national land cover map with tiny wetland selective schooling was produced in 1996 (NFA, 2006). However topical anesthetic observations cited in Ugandas recent assert of environment report indicate a reduction in wetland coverage, in the principal(prenominal) collect to conversion into crop land and spread of urban settlements (NEMA, 2007).While such conversions provide economic benefits from agriculture crop and real country ripening, they are too associate d with sociable costs primarily due to reduced or total loss of hydrological functions, habitat benefits and early(a) ecosystem services. One of the occurrenceors driving force these conversions is that the immediate economic returns to individuals outweigh the costs to the wider society associated with the loss of all- eventful(prenominal) ecosystem services.On a global scale, urbanisation is increasingly homogenizing the biota of slight(prenominal) developed countries. Even though urban sprawl is a oecumenic problem, most studies on the effect of urbanization on wetlands and the conceptual models defecate foc physical exercised on developed countries. South America has not break loose urbanization and therefrom has down the stairsgone the effects of urban sprawl and schooling. Pavements re position endemic wetland ecosystems and what is left of the natural ecosystem is predominate by non-native ornamentals species (Tolba and El-khoy 1997).capital of Uganda, Ugandas capital city has go through and through rapid population fuck offth of 5.61% per annum from 774,241 in 1991 to 1.2 one million million million 2002.The growth, which has occurred concomitantly with interchanges in population anatomical structure of the city, is influenced by rural-urban migration (UBOS, 2002). Population increase in capital of Uganda area is prudent for increased demand for employment, land for housing, social services and infrastructure that pee-pee stimulated spatial urban development and industrialization. delinquent to increasing rate of industrialization, which is an indication of development, galore(postnominal) people are coming into the urban centers to look for jobs. On the new(prenominal) hand, the employment opportunities are too few to draw in the labour, coupled with increasing population this scores an influx of laborers. This has had serious environmental consequences including wetland abjection, sedimentation of solid and toxic make o ffs in the wetlands and drainage channels (NEMA, 2001/2002).The current urban development is occurring in a haphazard manner largely dominated by the urban informality in most of the sectors (NEMA, 2001/2002). This has greatly contri howevered to the unsustainable custom of natural resources with in the area resulting in environmental degradation through solid waste accumulation, wetland encroachment, water pollution and land affair/cover change, which is reducing the ecological services from the natural environment of the area.Although Ugandas wetlands are saved by National Environment stature 1995, most of them are nonetheless beingness rescued and degraded, especially those outside protected areas. The environment and natural resource issue in Nakivubo division pose virtually of the most contentious, difficult and politically sensitive inviteions. in that locationfore,the future of our environment and natural resources seems to depend more on the trends in economic gains, social and political developments as well as outcome of litigation, legislation and administrative debates and decisions.In ecumenical the most outstanding issue colligateing urban wetlands is the increasing level of degradation in general from encroachment. Related to this issue are wardrobes, which include ownership of wetlands as property, and government/institutional policies. Other threats to the stability of wetlands are rustic conversions, industrial pollution, drainage and over harvesting of wetland resources.STATEMENT OF THE PROBLEMNakivubo wetland, one of the main wetlands in capital of Uganda zone, has suffered ponder(ip) encroachment in the recent past. A visit to the wetland reveals a lot of new activities, which signify recent broad encroachment. The activities include residential and commercial buildings and car washing bays among others. There is epochal reduction in the ve repayation cover, and the wetland now experiences more visible instances of swamp t han before during heavy rains. All these activities put a lot of pressure on the wetland, and affect its ecological function and ca enjoyment degradation. These activities are judgment to be a consequence of the increasing rate of development and urbanization in Kampala. Though there is insufficient data at the present to link urbanization with encroachment on Nakivubo wetland. The size and biodiversity of unconverted portions of wetlands has drastically diminished, with roughly areas completely converted. In 1993 it was noted that 13% of the wetlands in Kampala was severely degraded and by 2002 only 3.3% was remaining and was continuing to be degraded (NEMA, 2007). Housing, industrialization and infrastructure development play an important exercise in wetland degradation. This national ordain therefore examine the relationship amongst urbanization and the encroachment and degradation of the Nakivubo wetland, and suggest options for addressing the problem.OBJECTIVESThe overall objective is to examine the effects of urbanization on wetlands, using Nakivubo wetland in Kampala as a case study.Specific objectivei) To describe the types of activities in the Nakivubo wetland and their social-economic implications on the urban people.ii) Assess the sustainable management practices urban people use to improve on wetland ecosystem.iii) Assess the cognisantness of urban people towards wetland use and management.Research questionsThe following questions are dismissal to guide in my seek.i) What activities do you carry on the wetland and how do you benefit from such activities?ii) What management practices are you using not to degrade the wetland?iii) Are you aware of any government activity that protects wetlands?1v) what are your main sources of information concerning the saving of wetlands.1.5 Justification of the studyThe study forgeting evaluate the impact of urbanization on urban wetlands. The research is to examine how urban development leads to envi ronmental changes mainly through wetland degradation. Its to provide information on wetland degradation that is currently inadequate. Thus the research will guide National Environment Authority (NEMA), the National Wetland Program and other interested dissociateies to carry out appropriate actions to halt degradation of wetlands and develop more efficient wetlands conservation programmes. The information would further help district administrators like district environment officers to prepare action plans to improve local anesthetic wetland resource management and mobilize community efforts to participate in wetland conservation. The information will to a fault help urban planners in practicing sustainable development that is beneficial to the people but excessively environmentally friendly. It will provide knowledge to the local community on the effects of wetland encroachment.CHAPTER TWO books REVIEW2.1 INTRODUCTIONThe growth of urban and sub-urban areas has been a dominant de mographic characteristic of the 20th century. During this time urban population has increased ten-fold, and the relation of the human population living in urban areas has risen from 14 to over 50% (Platt, 1994). Much of this expansion of urban land, and citizenry has occurred a spacious coasts, as port cities keep expanded, coalesced, and engulfed neighboring undeveloped lands. Between 1960 and 1990, coastal counties in the US increased in population by 43%, a faster rate of growth than in the country as a whole. Likewise, between 1970 and 1989, nearly half of all building activities took place along the coasts (Anon., 1994). As of 1981, 28% of municipal areas were coastal, but they accounted for 55% of the US population (Walker, 1990). Elsewhere in the world, the story is similar of cities with populations over 1 million, 100% of those in South America are coastal, as are 75% of those in Asia and Africa ( Berry, 1990). Ugandas population growth also continues to be amongst the hi ghest in the world. The population in 2007 stood at 28.4 million an increase of 70 portion since 1991 and 16 percent since 2002 and the countrys population is expected to exceed 50 million and 127 million by 2025 and 2050 respectively, (NEMA 2007).Not surprisingly, the effects of this burgeoning coastal development on natural resources down been profound (Walker and Nordstrom,1990). Damage to and loss of wetlands hand over been colossal ( Tiner, 1984Dahl, T.E., Johnson, C.E., 1991. Status and Trends of Wetlands in the Conterminous United States, Mid 1970s to Mid-1980s. US Dept. Int., Fish and Wildlife Serv., Washington, DC.). A recent survey by the US subdivision of Agriculture found that urbanization was implicated in wetland loss in nearly all surveyed watersheds (96%) and may account for as much as 58% of the total wetland loss (Anon, 1997 ). Yet wetlands remain an integral part of social and economic stability and their continued disappearance should be of concern to everyo ne.2.2 HISTORY OF WETLAND MANAGEMENT IN UGANDAThe economic and ecological wealth represented by Ugandas wetlands, which cover 15 percent (31,406sq km) of its land area and are found in almost every sub-county, is well recognized by both its people and its leaders. Wetlands provide not less than 37 blue-chip services and products, and contribute hundreds of millions of dollars per year to the national economy (WID, 2001). Over 70 percent of all wetlands in Uganda are used for three purposes simultaneously water disposition, livestock grazing, natural tree harvesting, clay and sand mining, sport slanting and sources of crafts materials among other uses. In addition, they play a key aim in filtering pollutants and in regulating water flows, which in turn influence groundwater recharge, gourmandize impacts, and water availability during the dry season.Ugandas policy-makers pack acknowledged the importance of wetlands in the countrys Constitution (1995), which commits the governmen t to hold them, along with other natural resources, in trust for the common good of all citizens. Over the past 15 years, innovations including Ugandas Wetland Policy and decentralized wetlands management relieve oneself established a firmly foundation for more sustainable wetland management. Environmental and wetland concerns are also co-ordinated into several of the governments other primary policies, including the Poverty Eradication Action final cause, Plan for Modernization of Agriculture, and District Development Plans. The ten-year Wetlands Sector Strategic Plan, launched in 2001, identifies octonary key strategies to achieve sustainable wetlands management. Between 1995 and 2005, the Wetlands Inspection piece played out astir(predicate) $US 2 million to carry out wetland inventories for 30 Districts and build the National Wetlands Information System (WID and IUCN, 2005).2.3 URBAN WETLAND ENCROACHMENTHistorically, there are several accompanimentors that passel explai n as to why the wetlands resources charter and are still getting degraded in urban areas like Kampala. The major reason is rapid population growth leading to quest for extra land for cultivation and settlement. Extensive wetland resources both in the industrial and developing economies confound already been wooly or under issue increasing change due to conversion to aquaculture or industrial use. In his speech to scrawl the wetlands day 2010, Mafabi who is he? quoted that many wetlands around Kampala have been rescued and used for development purposes like building industries, rise growing, impunity and disregard of the law.Mafabi (1991), find that one of the reasons degradation of wetlands, in Uganda are the increasing number of landless people, who are forced to drain and cultivate wetlands due to pressure for agricultural land. Land in Kampala is very scarce and where its available, its very expensive, merely people really need land for agriculture and settlement. According to William (1990) and Njuguna (1982), reclaimed wetlands produce new soils, which are a basis of increased food production required to feed the rapidly growing population in developing countries. Since people consider wetlands to have very fertile soils and the fact that relevant institutions have turned a blind eye on encroachers, thus encroachers have interpreted advantage of these weaknesses to settle around and at heart these areas.Few people have demanded the protection and conservation of wetlands and these few who have tried are in most cases not noticed or are taken for granted by the authority (NEMA 2010). From my own local observation, some individuals use their profile for example high ranking officials or senior citizens to abuse these wetlands however much the in the public eye(predicate) complains. Finlayson and Michael (1991) noted that a fundamental cause of urban wetland loss in the past is that few people have demanded their conservation. Since other people are encroaching on the wetlands, many other individuals, even those who were campaigning for the conservation of these areas have lost hope and also encroached for their own benefits.On the other hand however, Dugan (1990), coincide that the main causes of wetland loss and exploitation are the secrecy and manipulation of information, the laterality of light-term private profit on long term public benefits. state are very much interested in short term private benefits without spending much from their pockets. Wetlands are not divinatory to be owned by private individuals or parties NES (1995), and therefore many people encroach on them because they are not dismissal to be asked for any land titles. Ntambirweki (1998) noted that many people are utilizing these wetlands because the economic policy for free goods is deficient and the land tenure system is not clear. Dugan (1990) goes forrader to state that deficient economic policy for free goods and hazardous and undocumented land tenure has also been a cause of the degradation of these wetlands.In my own view, there is lack of appreciation by people in these urban areas like Kampala of the extent to which these wetlands are important and are used by rural communities for purposes like domestic water, water for agriculture and some cultural values. The people in urban areas will therefore, continue to use the wetland for their development purposes. Citing some examples from the flood plains of the inner delta of the river Niger where the wetland exploitation is rampant, Dugan (1990) observed that one of the fundamental reasons for the drive to convert natural wetlands to other uses is a very poor international appreciation of the extent to which they are important and are used by rural communities. He therefore concluded that the absence of this catch on wetlands makes conservation difficult and unable to challenge the proposed changes, which are seen as being essential to economic development. both(prenomi nal) other factors that are influencing wetland encroachment are destitution related. These wetlands contain plants like paper plant, which people are harvesting and using to make goods like bags and mats (crafts) that they convey and earn a living(R. kabumbuli et al 2009). This in the long run affects the procedure of the wetland incase these plants are over harvested. They are also using the wetlands to grow rice for food and sale, making bricks and for fishing. All these activities contribute to degrading the wetland but are beneficial to the urban people for them to earn a living.ACTIVITIES CARRIED out IN WETLANDSToday, theres a growing concern to conserve and use wetlands in a sustainable way. Wetlands are more valuable economic resources in their natural state for certain objectives such as fishing, wildlife enhancement, aquaculture, water lineament improvement and flood control, compared to the gains from a modified wetland, (Barbier, 1994). By encroaching on these area s, their economic function is being greatly affected and can have adverse impacts. Many activities are going on in the wetlands of Kampala as a result of encroachment by wetland users. These activities may have significant implications on the wetland, which may be beneficial or corrosive to the wetland.Wetlands have been used for farming and for agriculture by many people. Crops such as yams and rice have been grown in the wetlands livestock is taken to the wetlands for grazing. Water for irrigation, domestic use and livestock is collected from these wetlands. The growing of some of these crops like the yams is beneficial in these wetlands as these yams play an important role in the cleaning up of the water since they remove some minerals and nutrients from the water (Njuguna, 1982). On the other hand, extensive growing of these yams can lead to ravaging of the wetland.The people practicing agriculture in these areas around wetlands have gone ahead to construct houses within the wetland so as to settle near their crops and also due to the fact that land is a scarce resource in urban areas. By constructing these houses, the flow of water in the wetland is disrupted and this in most cases leads to flooding mainly in the rainy seasons (Dugan, 1990).Settlement within wetlands has led to other associated degrading activities like brick making (Namanve wetland), sand extraction, and paper plant over harvesting (Kyengera wetland). Activities like sand extraction for construction of houses when carried out massively and brick making can have serious implications on wetlands as the sand that is removed is important in the filtration function of the wetlands (NEMA 2001/2002). This affects water filtration as a service provided by the wetlands. Over harvesting of wetland resources like papyrus for the purposes of making crafts so as to increase on the income of these people is also likely to affect the filtration and purification role of wetlands as these plants play a vital role in water purification in these wetlands.There are a variety of investments that are put up in these wetlands by reclaiming of the wetland to create land. Industries have been put up, churches have been constructed and other businesses like markets and shops have been developed with in urban wetlands. These are some of the major encroachments and activities going on in wetlands worldwide and in Kampala. A lot of land has been reclaimed and used for constructing of big industries in the urban areas due to development, which has resulted in shortage of land for the construction of these industries and factories. The reclaiming of these wetlands so as to create land for construction has been a great cause of flooding (Mitsch and Gosselink 1990). On the other hand, this creates and provides land for development and settlement in urban areas.Due to development, there is need for roadstead with in these urban centers and therefore, some of the roads that have been constructed have encroached on the wetlands and others have been constructed either adjacent or within wetlands, which has affected the execution of the wetlands. Roads constructed adjacent or within wetlands increase on the level of silting in the wetlands and they also disrupt the flow of the wetlands since this can lead to the diverging of the wetland (Anibal and Aguayo, 1995). There is also a likelihood of these roads breaking down after some time therefrom affecting many people.Within wetlands, activities like fishing and aquaculture are being carried out. People depend on these activities to earn a living and for backup support. Fish ponds have been constructed to culture fish near these wetlands. Wetlands both permanent and seasonal especially along the lakeshores are an important source of fish for the local community. The interface zone between the swamp and the open water is an important breeding ground for commercial fish including tilapia (William, 1990). Its also a home to many aquatic and wildlife species and birds. Extensive fishing can lead to over exploitation of the fish species, which are of importance in the ecosystem. This in the long run may affect the ecological functioning of the wetlands since it affects the food chain.AWARENESS TOWARDS WETLAND USE AND MANAGEMENTIt should not go unnoticed that, historically, many wetlands have been misconceived to be waste lands. Consequently, they were bushed(p) or degraded by human activity without factoring in their numerous functions, benefits and values, (William, et al, 1990). Wetlands were also regarded as bogs of treachery, mines of despair, homes of pests, refuge for out laws and rebels, (Williams, 1990 Mafabi, 1991). A good wetland was a drained one, free of this mixture of dubious social factors, (Dugan, 1990).Lack of awareness is the major cause of the increasing deterioration of biodiversity in urban areas of developing countries (Anibal Pauchard, 2005). ordinary awareness of wetland issues is i ndeed a key tool in wetland conservation and must be part of any attempt to change attitudes and style patterns. Many people living around wetlands are not aware of the impacts they are likely to cause to the wetlands in relation to their practices and in the long run have continued using the wetlands in a way that is degrading them. Some, who are aware close the impacts they can cause on the wetland, have had very poor attitudes towards the information they have been given and have continued to use the wetland in a manner that is not sustainable.In order to alert the public on the values and functions of wetlands and the need for their sustainable use, the national wetlands programme (NWP) has developed an awareness campaign consisting of videos, audio tapes, posters, leaflets and booklets (NWP, 1997). Newspapers have carried features on wetlands songs have been developed to supplement radio and television programs. cognizance seminars and outreach programs are also carried out. The target groups are farmers, resource users, schools and district development committees.There have also been various efforts to promote environmental forthwithion through formal education in schools especially the wildlife club of Uganda. to a fault NEMA has tried to put up programs in various schools to promote environmental protection. All this has to some extent raised awareness and concern approximately wetlands among Ugandans (NEMA, 1998). Many Ugandans including grass root communities, policy makers, and natural resource planners plot aware of environmental problems have little commitment to environmental conservation (NEMA, 1998). This may be because majority of the population living in poverty under constant threats to food insecurity is so concerned with basal survival matters that theres not much room to be concerned about(predicate) environmental issues such as proper management of wetlands.Institutional understanding of the value of wetlands and associated inve stments in wetland has grown in Uganda. Similar changes in peoples perceptions and attitudes of wetlands have given rise to arrange of conservation initiatives in wetland management. In Uganda, for instance, the Ministry answerable for environment protection is elaborating a national wetland policy in direct response to rising local concern over environmental and social consequences of wetland loss.Generally, the cumulative importance of wetlands has gradually developed because of the growth of knowledge about their numerous functions, values and threats documented by various researchers. In fact the Wetland Inspection Division in Uganda regarded the wetlands as wealth land because if well managed, the products and services can be reaped in perpetuity. And thus they are outlay conserving and wisely utilized.CHAPTER THREE methodologyThis section focuses on the study methodology.ie. take in area, sample selection procedure, data collection technique, entry, processing and analysis that is going to be used.STUDY AREAThe study is going to be carried out on Nakivubo wetland. The wetland forms the boundary between Nakawa and Makindye divisions in the valley between Bugolobi, Mpanga and Muyenga hills (ADF). It is for good water logged and is fed by the Nakivubo channel. It is one of the major wetlands on the north-western shores of Lake Victoria. The study will specifically be carried out in Nakawa Division, Kampala district. Nakawa Division is in the eastern part of the city, bordering Kira town to the east, Wakiso district to the north, Kawempe division to the northwest, Kampala central to the west, Makindye division across Murchison bay to the southwest and lake Victoria to the south.it covers an area of 47.45square kilometers (18.32sq.mi).Map of Nakivubo Wetland(Source Emerton et al., 1999)Study populationThe study population involves mainly farmers, brick layers, residents, builders and other individuals who are greatly involved in the use of the wetland e. g. People involved in putting up of business like shops and schools in this are also going to be interviewed to get more information on the study objectives. The area is estimated to have a population of 135,519 people. meteorology of Nakivubo wetlandThe Nakivubo swamp is within the equatorial belt, and has a moist sub-humid climate. It receives a bi-seasonal rainwater in the periods of March to May and September to November. The rainfall is linked to the suppress Tropical Convergence Zone (ITCZ), the altitude, local topography and the lake. Short duration equatorial thunderstorms are particularly common around Lake Victoria and Kampala. The latter is account to receive more thunder storms than any other capital city in the world (Kansiime et al 1999). This rainfall frequency and reliability upgrade the formation of peat lands and swamps. The presence of a large adjacent water body also ensures a both reliable and fairly stable hydrological government activity (always humid, a nnual water level variations about 0.5 m). This is a requirement for papyrus, the dominant wetland macrophyte in the Nakivubo swamp.Geology of the swamp areaThe soils of the Nakivubo swamp area are alluvial and lacustrine sands, silts, and clays overlying granite gneisses. Indeed the gneisses overlay most of the Lake Victoria wash-hand stand north of Kagera River, the main tributary of Lake Victoria located in the SW (Kansiime et al 1999). Within the swamp, the alluvial soils range from semi-liquid organic material in the very upper layers of the emergent vegetation zones, through reddish ferruginous (high confine of dissolved iron in run-off water) loams to clays.Drainage of Nakivubo SwampThe major come up water drain into Nakivubo swamp is the Nakivubo Channel. In addition, Port Bell and Luzira waste water channels and a number of minor culverts discharge their water (some seasonally) into the lower Nakivubo swamp. The catchment area into the lower Nakivubo swamp is about 1.1 k m2 from the Luzira watershed, 2.5 km2 from the Bukasa watershed and about 50 km2 from the city centre via the Nakivubo Channel and the upper Nakivubo swamp. These, with the exception of Luzira Prisons sewer water and the Nakivubo channel, also carry rainfall and contribute disparate amounts of water into the swamp.METHODOLOGYRESEARCH DESIGNThe study design will be distinguish hit-or-miss sampling. The study area is going to be stratified on political unitsat what level?. The political units surrounding Nakivubo wetland are Bukasa, Kisugu, bugolobi, luzira prison and Mutungowhich political units are these?.One division is going to be chosen purposively basing on its availability from town due to limited finances, from which two parishes are going to be picked and from each parish 25 peoplewhy 25 and not more or less? will be interviewed by choosing the fifth housewhy the 5th and not any other? after each house with the head of the householdwhy the head and not any other member o f the household? being the target for interviews. schools, shops and gardens are going to be considered as plots (houses).what does this mean?SAMPLING AND SAMPLE surfaceThe study population is going to be obtained by stratified random sampling its objective is to reduce bias by sampling different strata. Stratification is going to be based on administration units. A Sample of 50 respondents is going to be interviewed using questionnaires and these are going to be obtained randomly. This is because of logistical, time and financial constraints. This contradicts your research design, which is which?DATA COLLECTION entropy collection is going to be by primary data obtained at a time from interactions with responds in the field and secondary data from library books, peer reviewed journals and government offices. The principal research technique in primary data collection is going to be by use of questionnaires (to answer all objectives),which are both closed and open ended, and are go ing to be administered by the way of direct interview with respondents. The open-ended questionnaires are going to pass on multi-response that will shade more light on the subject matter. The interviews are going to be carried out in both Luganda English. Direct observations use of a camera are going to be used to get detailed information. Using a map of the area, a transect walk is going to be carried out to get a general view of the area. identify INFORMANTSKey informants like environment secretaries and officials from environmental organizations (NEMA, WID) are going to be interviewed to get more valuable information on all my objectives. This will help me get firsthand information about the problem under study. It also helps to correct anomalies from questionnairesand leads to collection of in-depth data Is this true?.FOCUS convocation DISCUSSIONS (FGDs)Focus group discussions (FGDs) are going to be carried out with some purposively selected respondentswhat purpose?. The FGD s are going to confirm the gathered information from questionnaires.what comes first, FGDs or Surveys? Further more they will give exploratory, illuminating and enlightened data. much(prenominal) information will provide insight into attitudes, perceptions and opinions of participants. FGDs give participants ample opportunity to comment, explain and share experiences that were not available from individual interviews, questionnaires or other data sources and therefore views got from such d

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