Day 1

Notes from Dr. A. Mata

General overview of Costa Rica

1. Continental drift of plates from a Supercontinent: Separation of plates: North and south American plates (250 x 106 years)
2. Marine volcanic rocks origin (180 x 106 years) from hot spot near Galápagos
3. Subduction between El Coco and Caribbean plates (75 x 106 years)
4. Emerging islands between North and South American continents.
5. Volcanism started. Formation of the volcanic range and volcanic deposits. Termination of a bridge.
6. Starts a period where northwest is volcanic active and south is not. Thickness of Caribbean Plate in CR is 20 km Pacific-South, and 40 km in the volcanic mountain range of Guanacaste.
7. Thickness of Coco's Plate bottom is 6 km. Thickness of sediments along bottom of the Pacific near CR sector is 2 km
8. The massive mountain range system that runs the length of the Republic of Costa Rica in Central America, with a NW-SE orientation, creates two principal versants or basins with similar areas. The Pacific basin covers 50% of CR territory modeled by a network of rivers whose flow and eroding behavior is determined by marked climatic seasons. The Caribbean watershed has a more homogeneous and much more humid climate nearly year round; this large basin is divided into two main watersheds. Precipitation averages 3500 mm/year

The Chorotega Region (Northwest of CR)

1. Mesozoic volcanic/sedimentary rocks (135 x 106 years, cretaceous) crop up extensively in the Peninsula; Bagaces and Liberia formations, sedimentary rocks of the Quaternary in the Tempisque River Basin (TRB). Ignimbrite deposits (7 x 106 years)
2. Recent volcanic activity (Holocene, 150 - 20 x 103 years)
3. Main alluvial sedimentation forms are located in the flat, lower parts of TRB
4. Geothermal energy, earthquakes. The subduction process of the Coco's and Caribbean tectonic plates is determinant in the whole country and constitute a high probability of a strong energy release in the entire Chorotega region.
5. Valleys of varying sizes, with high fertility soils (Tempisque, Curime, Nacaome, Nosara) and poor soils (ignimbrite deposits of Liberia-Cañas)
6. The Pacific slope particularly the Northwestern part of Guanacaste, is characterized by a dry seasonal climate, represented by the tropical dry forest life zone with its transitions, and the tropical wet forest of atmospheric association, that is characteristic of the Peninsula of Nicoya (Life Zones Classification System by Holdridge).
7. The coastal hills and mountains determine the watershed of the northwestern coastal strip, which begins at the border with Nicaragua and ends at the southern tip of the Peninsula).
8. The southern region of the Peninsula of Nicoya has annual precipitation, between 1,800 and 2,300 mm; the least abundant rain is located in the central and northwestern zones of the TRB, with around 1,400 mm/year. The monthly mean temperature lies between 24 and 30 ° Celsius.
9. Strong trade winds are predominant during the dry season, with speeds between 10 and 30 km/h and gusts of roughly 60 km/h. Winds from the Pacific during the rainy season, bring humidity (3 and 8 km/h).
10. The main geohazards of the region are of hydrometeorological nature during strong rainfall and storms, which in some occasions are indirect effects of hurricanes originating far in the Caribbean, but always having strong repercussions. Due to the vulnerability caused by uncontrolled human activity (deficient urban planning, urban invasion of susceptible lands), there are damages from floods, avalanches, and landslides, as well as from hydrological erosion. They occur in the floodplains of rivers and in steep slopes, and they affect crops, bridge infrastructure, roads, and urban areas, particularly in the typical wetland sectors of the Tempisque, Cañas and Las Palmas rivers. However, these lands have been overtaken by agricultural activities, settlements, neighborhoods, and even cities. Although the National Emergency Commission acts efficiently during the disasters, there is no ordinance for the obligatory construction of appropriate houses (e.g. perched on piles), or for the development of urban centers on more elevated lands. Levee construction continues in the Tempisque River banks, without environmental studies or official restrictions.
11. Biological importance of the isthmus bridge since the emergence of Mesoamerica.
12. General and complex interactions in the watershed.
13. Importance of the stream corridors.

14. Picture 5.3

Our Summary:

Costa Rica is home is many volcanoes, both inactive and active. These volcanoes influence the topography/landscape and the people of Costa Rica.  The active volcanoes are in the north and the inactive volcanoes are in the south of the country.   Geothermal energy is actually produced by these amazing natural features.  Geothermal energy is produced when steam under the ground is harnessed and converted into energy to be used by the people.  In addition, the ashes from the volcanoes produce fertile soils for agriculture.

The northwest part of Costa Rica is called the Chorotega Region. Nosara is in this region, on the Nicoya peninsula. In this region there are many volcanoes and about 40 are active today. The chain of volcanoes and mountains affect the area in many ways. When volcanoes erupt, the lava flows down the mountain making it difficult for plants to grow. At the same time, ashes spew from the volcano and land in the valleys. The ashes make a very fertile soil. People grow crops like rice, mangoes, and sugar cane in the valleys.

Costa Ricans also harvest energy from the volcanoes. Power plants are built to collect steam under the ground in areas around the volcanoes, normally the steam would be released as the volcano erupts. The power plants convert the steam into energy for homes and businesses. There are many streams and rivers running down the mountains into the Pacific Ocean to the west or the Caribbean Ocean to the east. The land that borders the rivers, or the riparian area, is important for wildlife habitat and erosion control. The riparian areas in Costa Rica are protected from development.

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Day 2

Notes from Dr. A. Mata

Environmental characteristics of the Chorotega Region

1. Life Zones. The bioclimatic diversity of the Chorotega region is reflected into seven life zones with various transitions. Influence of general fisiography.
2. The tropical dry forest zones, strongly seasonal, and the related transitions to moist forest, constitute around 30% of the whole Chorotega region. It is here where the largest extant territory of dry forest in the Pacific side ecoregion of Mesoamerica is protected. The tropical moist forest predominates, particularly in the Peninsula of Nicoya. The greatest biodiversity is produced in the Guanacaste and Tilaran mountain ranges, where several life zones are found as narrow altitudinal bands surrounding the volcanic mountain chain.
3. Protection and biodiversity conservation. National Protection Areas (SINAC) and other preserves. Monteverde Rainforest Preserve case (run by Tropical Science Center). Conservations efforts from some communities often collide with individual interests, and by the time the Government intervenes, a habitat has already been cut down or a protected land invaded.
4. Flora and Fauna. Different life zones of the area hold an ample biodiversity. Still has a rich flora and fauna. 345 species of birds, 114 of mammals and many herps. The dry forest provides a wide variety of habitats.
5. There are 32 endangered bird species, 12 of mammals, and several hard wood tree species having commercial value. Some animal species are considered plagues because of alleged damages done to agricultural activities and domestic animals
6. Wetland ecosystems are abundant in Guanacaste, particularly around the Gulf of Nicoya. Represent 20% of the area of the TRB, that is 1,025 km2, not including the riparian area or upper lands. These ecosystems present conditions of great ecological, economic, and social value, and the inhabitants of the region have exploited them throughout history. In the case of middle TRB area, the continuous invasion of wetlands by agriculture has brought about a notoriously negative impact. Those influenced by tidal estuarine waters are located near the Tempisque River mouth (near Palo Verde National Park) and surrounding the Gulf of Nicoya. The natural vegetation can be herbaceous, such as gramineae and cyperaceous shrubs, floating and submerged aquatic vegetation, rooted vascular plants, mangroves.

7. Picture 5.4

   Restoration ecology. In the last 25 years, important sectors of the forest habitat in the Peninsula of Nicoya have naturally recovered (secondary growths), after the recession of cattle ranching in the 80's; many species of mammals and birds have noticeable increased their populations. This is an important achievement, because Guanacaste is one of the regions of Costa Rica where the wildlife has suffered the greatest negative impact, due to the loss of natural habitat, over exploitation with extensive cattle ranching and agriculture, poaching and hunting sports, particularly during the middle years of last century. The ocean hunting of turtles and dolphins, as well as the over fishing at the Gulf of Nicoya estuary has prompted legal actions for environmental protection.
8. Scientific literature produced in the area is large. The National Institute of Biodiversity example initiated a project for a total species inventory of the country; several projects in environmental education. There is a need for simple but important studies, such as the population status of endangered species, both in land and aquatic habitats and stream corridors. With this respect, the State, research institutions and the community must act together to achieve positive and solid progress in the field of conservation. Important biological research stations like those of Organization of Tropical Studies (OTS)

Freshwater Resources

A hydrological connection exists among the different terrestrial, fluvial, and estuarine systems in the region. This connection obviously involves the habitats drained by the river web, with all the ecologically related species (birds, bats, butterflies, bees, mammals, fish, humans, etc.). However, biological and ecological studies on the biota of dry forest watersheds and connecting uplands are scarce.

1. In general, riparian ecosystems have the following properties:
   1. Protection and stabilization of the soil infiltrated by water, or saturation zone, the transitional upland fringe, of high surface runoff, where erosion and nutrient washings are greater in the watershed
   2. The system works with multidimensional dynamics.
   3. Retention of sediments, organic matter, and pollutants that could reach the river from the surrounding areas, by mulch and underbrush vegetation
   4. Source of nutrients and species for other rivers (down the watershed), lagoons, lakes, estuaries, and the ocean
   5. Control of water temperature of the creeks, favoring aquatic life, and increasing the dissolved oxygen retention capacity; forest shade plays an important role
   6. Biodiversity conservation, biological corridor, and wildlife species refuge during the dry season and the migratory season
2. Other benefits are derived from aesthetic aspects, shade, outdoors sports, industrial and commercial transport, water provision for agriculture, industry and homes, and other environmental services. Stream corridors are important to connect larger areas of natural habitats, at different altitudinal levels; they must be protected in and outside the officially preserved areas (like national parks and refuges), from the water heads to the seashore.
3. There are low coastal mountains in the northwest coastal sector of the Nicoya Peninsula (50 to 250 miles above sea level) from which creeks and a few rivers are born, their microbasins emptying directly into the Pacific Ocean. The majority remains waterless during the dry season, but they rapidly flood with the strong and persistent precipitation of the rainy season. All these rivers are born in the driest Life Zones of the country, such as the tropical dry forest, the moist forest, and the premontane moist forest. The Nosara River and the Bongo River, the two longest and most affluent, maintain a perceptible base flow from March to May.

Rivers that flow to the Gulf of Nicoya

1. The land of the GNB covers around 12,000 km2, almost one half of the Pacific Ocean versant of Costa Rica. Such a vast extension is important not only because it covers almost 25 % of the national territory; presents a set of varied terrestrial and aquatic ecosystems and almost all the life zones occurring in Costa Rica. The most extensive hydrological sub region in the Guanacaste Province, with an average annual flow of 308 m3/s, is located in the center, that of the Tempisque River Basin (TRB). Most of the seasonal dry forest and related transitions are found there. With the Central Valley of San Jose, they compose the backbone of the national economy.
2. The Lake Arenal sub-basin, after the Arenal River was dammed, resulting in its lake area increased to 84 km2 and its volume considerably enlarged, it was incorporated into the Pacific slope. This artificial connection, which supplies ca. 90 m3/sec., established the largest hydrological utilization ever assembled in the country, for the purposes of hydroelectricity production in three cascading power plants (Arenal, Corobici, and Sandillal), and irrigation with three principal channels that supply flat lands of the Bebedero River sub basin.
3. The Tempisque River Basin comprises the watersheds of the Tempisque and Bebedero rivers. This entire lowland region covers approximately 1,300 km²; it is a floodplain, 80% of it can be considered a wetland, and the majority of the area is intervened by agricultural activities (sugarcane, melon, rice). This river should have top national priority in any decision regarding protection and ecological restoration.
4. The TRB has an area of 5,454 km²; its ethnographic and archaeological contribution is one of the most relevant in the history of the country.
5. The Bebedero basin receives the flow of 90 m3/sec, an important impact derived from the Arenal-Corobici-Sandillal Hydroelectric Project. Part of this water (ca. 60 m3/sec) is then used in the Arenal-Tempisque Irrigation Project for the intensive cultivation of about 18,000 hectares under the supervision of the National Irrigation and Drainage Service; the development can eventually reach 30,000 hectares.
6. Groundwater resources and problems.

Our Summary:

Costa Rica is about 1/3 the size of Florida, but it is extremely rich in flora and fauna (plants and animals). The Chorotega Region can be divided into 7 life zones, each zone having different types of plants and animals. Just in this region of Costa Rica there are 345 species of birds, 114 species of mammals, and many reptiles and amphibians. There are also endangered animals, 32 birds and 12 mammals.

Riparian areas and rivers are important to Costa Rica and the Nosara area. Riparian areas are important because they protect the river and soil around the river from erosion, provide a source of nutrients for animals in the waterway, control the temperature of the water, and provide habitat for animals.

In the Nosara area, the forests are secondary growth, most trees are around 30 years old. This area was mostly agriculture and grazing in the past and in the 1970’s a developer bought a lot of the land. He was going to develop the area for tourism, but the plan failed and today Nosara is covered with trees and vegetation. There are some small farms, rice fields, and mango groves in Nosara and the surrounding area.

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Day 3

Notes from Dr. A. Mata

Environmental and Socio-economical Characteristics of the Chorotega Region Environmental Impacts

1. Main production limitations of the soils: long dry period, strong winds, shallowness and/or stoniness. Many sectors with little slopes are classified as lands for watershed protection (e.g. north of Bagaces and Liberia and the hills of the Peninsula of Nicoya).
2. Main economical activities: Rice, cattle, sugar cane, non-traditional crops, tourism (tropical dry forest zone). Cattle ranching was initiated 1880 and 1930-50.Demographic pressure from the Central areas. From the 30´s and 40´s the activity was incremented due to international demand and protection of the sector. The golden epoch 1950-1970, being CR the fourth exporter to USA. Since 1988 the activity has deeply diminished, due to low prices, inflation and les incentives.
3. Mango. Important for the region. Low expansion. 74% is for national market, 20% wasted and 6% for export. Arenal-Tempisque Irrigation System favors rice paddle system, with 3 annual crops; internal consumption. In spite of adequate soils and excellent climatic conditions, international prices are erratic.
4. Sugar cane was introduced in Guanacaste and Puntarenas by the Government to promote colonization of lands. High levels of technology. 45% for national production. Molasses destined to alcohol production, exporting to USA and Spain.
5. During the first half of the last century, deforestation was very extensive in the whole region, but particularly in the low lands during the period 1940-1965, after World War II, with the opening of the Pan American Highway. After the cattle ranching decline, at the end of the century, and regardless of the recovery efforts in many hills, the effects of tree cutting are still noticeable in the inner parts of the Peninsula coastal mountain range. Among the regions of the country with the highest land use imbalance.
6. A considerable part of the Guanacaste floodplains is used for agricultural purposes and for some urban and semi urban areas (like Filadelfia and Ortega); these zones are extremely vulnerable since they have invaded wetlands and plains with recurrent flooding. There are no ordinances for the safe construction and location of urban developments in these areas.
7. Ecotourism. It has gained strong momentum since 1987. One of the main incomes of CR. Guanacaste has several attractive protected areas, product: tourists, direct and indirect income.

Environmental Impacts

1. Erosive processes are present, of hydrological character and a bit of aeolian. Sediment load in rivers is directly related to improper land use and coincides with the rainy season (May to November), particularly in the hills of the Peninsula of Nicoya, microbasins producing large quantities of water during short periods; landslides and fast floods are frequent during the strong and sustained rainfalls of September and October, particularly under the influence of the tropical storms in the Caribbean basin.
2. The impact on the riparian system, which had been traditionally protected, is visible in many rivers in Guanacaste and, in general, nationwide. The fluvial-riparian continuum is essential to maintain the biodiversity of the ecosystem. Each bridge, road, or crop along the river bands results in various degrees of fragmentation, which could be prevented by appropriate measures as well as the enforcement of current laws.
3. Thousands of hectares were affected by the fires from 1997 to 1998, in part due to the effects of the El Niño; the old custom of slash and burn is still a problem during the dry season.
4. Water consumers. Once the resource is used, those consumers become producers of contaminated water, in varying degrees of output. The most relevant: sugar industries, coffee mills, fruit packaging plants (melons), Arenal-Tempisque Irrigation System, aquaculture, cities, and towns.
5. Fluvial morphology alteration, channeling and dam construction for water deviation and containment, as well as intervention of the riparian forests. If the sugar cane expansion in these fragile areas is not regulated, there will probably be more intervention with channels, levees, and fluvial detours, which would bring about the certain alteration of nearly all wetlands in this region. There is no legislation that regulates levee or channel construction, and a part of the population (which suffer the emergencies of floods) feel that this infrastructure, built without specific environmental planning, is contributing to the prolonged containment of floodwater in the middle TRB.
6. Various types of pollution, being that of water the most relevant, in the forms of sewage, waste waters of industry and urban centers, as well as coming from agriculture activities. The initial capacity of the sewage treatment plants of urban areas was reached some time ago and cannot handle the wastes produced by new urban developments.
7. Point source pollution is generally caused by the discharge of urban wastewaters, tourist developments, industry (sugar mills), mining, pig farms, tilapia aquaculture, and garbage dumpsites. The legal frame for pollution control in the country is sufficient. Drawbacks: lack of regular monitoring, reinforcement of the laws, application of new technologies and a limited capacity for the governmental offices in charge of monitoring. Several agreements between the government and the sugar industry have yielded good results (as well as with coffee mills and a few pig farms).
8. Non-point sources of pollution come from the use of chemicals in agricultural areas, as in the extensive rice paddies. There are no studies (on a regular basis) on this subject. Added to the pollution from the Central Valley basin, the contamination of the TRB has repercussions on the Gulf of Nicoya that are yet to be estimated.
9. The maritime zone consists of a inalienable 50-meter land strip starting from the high tide water level and all the surface uncovered during low tide, and includes any extension covered by estuaries, mangroves, coastal lagoons and floodplains. The interior band of 150 meters of continental or insular land constitutes the restricted zone. According to the law, both contiguous bands should be under protection and careful management of urban, tourist, industrial or agricultural developments. However, there are very serious transgressions. This anomaly may contribute, paradoxically, to the destruction of the natural attraction that is in itself the driving force for the tourist development and a reason for overseas environmental prestige of the country. This problem is of special relevance in the Chorotega Region.

Picture 5.5

Our Summary:

In the Chorotega Region the main economic activities are rice, cattle, sugar cane, non traditional crops, and tourism. Ecotourism has been growing since 1987 and is becoming an important income in Costa Rica. In order for ecotourism to remain strong and for the environment to remain healthy, Costa Ricans must deal with some environmental concerns. Erosion is a problem because of the intense rainy season, landslides and flash floods are frequent during September and October. Clear-cutting trees and exposing soils to rain causes landslides and flash floods. Protection of riparian areas needs to be enforced because urbanization and slum settlements are encroaching on some riparian areas. Costa Ricans and visitors need to be aware of water conservation practices. Not only is the population growing, but agriculture practices use a lot of water, also. Water can be polluted by point source and non-point sources. Point source pollution comes from one place, examples being urban wastewaters, tourist resorts, industry, mining, farming, and garbage dumps. Non-point pollution comes from a general area like chemicals used in agricultural areas. Beach fronts, the first 150 meters of land from the ocean, are protected from development, but the Ministry of Environment and Energy and the Tourism Ministry do not always enforce this law.

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Day 4

Notes from Dr. A. Mata

The Gulf of Nicoya Basin and Coastal areas

1. Definition of the GN as an estuary
2. The Tempisque River Basin, with a variety of ecological, cultural, and socioeconomic resources, composes one half of this large estuarine-terrestrial basin. If the Tarcoles River watershed, that drains in the lower sector of the GN, is included, the whole area represents as much as 25% of the country of Costa Rica.
3. It has become clear over the past decades that the deforestation of the watershed has lead to a reduction on the average flow of the Tempisque River in the dry season, and to an increase in the magnitude of the floods during the rainy season.
4. Important grounds for fisheries of CR

Environmental Impacts

1. Environmental Economics study showed (1991) a clear decline of the fishing resources; it is determined that since 1983 there is a significant and steady decline in the total fish capture in the GN, with a concomitant increase in the fishing efforts necessary to obtain the same capture.
2. Old sewage treatment plants built around 30 years ago and the actual coverage is only around 30% of the cities' needs, and are showing a decrease in their yield. The rest of the urban centers use septic tanks and latrines.
3. Deaths of shrimp and fish in the TR were observed several years ago; mortality was associated with the presence of pollutants introduced by washings and land erosion coming from the agricultural activity around the Gulf, and by the presence of organic wastes of the sugar cane industry that depletes the oxygen content of the water. The sugar factories have improved their anti pollution measures. On the other hand, the fast growing aquaculture of tilapia fish in ponds poses and increasing demand for freshwater and disposal of residues.
4. The presence of organochlorine pesticides was studied in the 80's, in eggs of 8 species of aquatic birds at Isla Pajaros, near the mouth of Tempisque River. The study revealed low residues of DDT, in the detection limits, around 10 µg/g of dry sample.
5. Heavy elements at very low levels.
6. Pesticide contents in the TR waters are very low. Mercury contents found were in environmental normal concentrations. All these studies are not conclusive enough; there is no systematic sampling, including water and animal tissue samples.
7. Rice is growing in the lowland area, stimulated by the availability of water for irrigation. Because of a more rational aerial and terrestrial applications, it is speculated that the potential impact of the over use of pesticides and inorganic nutrients is actually less intense now than in former years. However, other agricultural products could be introduced, which might require important inputs of nutrients and biocides. Urgent need for research on the biota and limnological characteristics of the Tempisque River, particularly in the dynamic zone where the river mixes with ocean waters.
8. Urban garbage management is inefficient, and the dumping continues to pollute rivers and estuaries. Several reasons affect the solution to this problem: uncontrolled urban development, lack of public awareness and education, and poor governmental assistance for appropriate waste management of the municipalities.
9. The Puntarenas Estuary case
10. Impacts or Tarcoles River watershed. The Central Valley of San Jose (Capital City of CR)

Picture 5.6

Our Summary:

Take a look at the Gulf of Nicoya. Can you tell that this water formation is an estuary? An estuary is the wide part of a river where it nears the sea. The Tempisque and Tarcoles Rivers both drain into the Gulf of Nicoya. Can you think of reasons as to why increase flooding has occurred around the mouths of the Tempisque and Tarcoles Rivers?

Yes, it is true that people must work hard to sustain the environment. However, our impact is very clear around the Gulf of Nicoya Basin. First, because the population has increased, there are not enough sewage treatment plants, and the ones that do exist need to be updated. Second, agricultural activity is causing pollutants to wash into the gulf and lots of shrimp are dying. What will happen to the shrimp fishermen? What will happen if farmers start to use new pesticides?. Third, garbage continues to be dumped into the rivers which further pollutes the estuary. Remember, a sick river can be a sign of a sick ecosystem.

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Day 5

Notes from Dr. A. Mata

Population Growth in Mesoamerica and Threats to the Environment

1. Trends in species extinction
2. Future trends in water availability
3. Deforestation process in Costa Rica
4. Water pollution projection
5. Trends in urban population growth in Central America
6. Trends in world population dynamics
7. Trends in contemporary stile of development
8. Projection to the future
9. Necessary measures to prevent environmental destruction and reduction of sustainable development options.

Our Summary:

As medicine continues to advance and people become healthier, populations increase. This is also true in Costa Rica. As more people appear, more species become extinct. There are concerns about water availability and many of Costa Rica's forests are being destroyed. Also, more people will result in more polluted water. It is the world's responsibility to help Costa Rica take the necessary measures to prevent environmental destruction.

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Next, is our scrapbook (photo gallery and personal notes).

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