Hartmut Gaese - Academia.edu (original) (raw)

Papers by Hartmut Gaese

Agricultural Engineering International Cigr Journal, Dec 30, 2008

Iahs Red Book Series Iahs Publication, 2010

The present paper is based on a literature review and aims to tackle the most important aspects r... more The present paper is based on a literature review and aims to tackle the most important aspects regarding the topic wastewater reuse with some recent examples, focusing on reuse in agriculture. Still in some countries the institutional and legal framework is weak or not existent or only referring to international standards (guidelines or laws) which are very general and most of the times demand very cost intensive solutions. An integrated planning approach is therefore necessary in case reuse of wastewater shall be one management alternative in a water stressed basin. Here the technological, economical and health aspect as well as the legal framework have to be considered. Therefore reuse of water is an interdisciplinary challenge for the present and for the future.

Land use intensification, urbanisation processes and the construction of the largest Brazilian pe... more Land use intensification, urbanisation processes and the construction of the largest Brazilian petrochemical complex in Rio de Janeiro are driving ecosystem services degradation in the Guapi-Macacu watershed. This watershed supplies 2.5 million urban water users and sustains farming systems, relevant for national and local food supply-related governmental programmes. Development pressures will probably increase further the demand for watershed services and threaten local food production by rising labour costs in the agricultural sector. Paying farmers to restore watershed services has been proposed to secure long-term water supply. This study quantifies the costs of changing current land use patterns to enhance watershed services and compares these to avoided water treatment costs considering tradeoffs with food provision. We use farm-household data to estimate the opportunity costs of land use changes that are known to improve water quality. Opportunity cost estimates are extrapola...

Resources, Conservation and Recycling, 2014

ABSTRACT Runoff water management is among the inherent challenges which face the sustainability o... more ABSTRACT Runoff water management is among the inherent challenges which face the sustainability of the development of arid urban centers. These areas are particularly at risk from flooding due to rainfall concentration in few heavy showers. On the other hand, they are susceptible to drought. The capital of Sudan (Khartoum) stands as exemplary for these issues. Hence, this research study aims at investigating the potential of applying rainwater harvesting (RWH) in Khartoum City Center as a potential urban runoff management tool. Rapid urbanization coupled with the extension of impervious surfaces has intensified the heat island in Khartoum. Consequently, increased frequency of heat waves and dust storms during the dry summer and streets flooding during the rainy season have led to environmental, economical, and health problems. The study starts with exposing the rainfall behavior in Khartoum by investigating rainfall variability, number of raindays, distribution of rain over the season, probability of daily rainfall, maximum daily rainfall and deficit/surplus of rain through time. The daily rainfall data show that very strong falls of >30 mm occur almost once every wet season. Decreased intra- and inter-annual rainfall surpluses as well as increased rainfall concentration in the month of August have been taking place. The 30-year rainfall variability is calculated at decade interval since 1941. Increasing variability is revealed with 1981–2010 having coefficients of variation of 66.6% for the annual values and 108.8–118.0% for the wettest months (July–September). Under the aforementioned rainfall conditions, this paper then explores the potential of RWH in Khartoum City Center as an option for storm water management since the drainage system covers only 40% of the study area. The potential runoff from the 6.5 km2 center area is computed using the United States Natural Resources Conservation Services method (US-NRCS), where a weighted Curve Number (CN) of 94% is found, confirming dominant imperviousness. Rainfall threshold for runoff generation is found to be 3.3 mm. A 24,000 m3 runoff generated from a 13.1 mm rainfall (with 80% probability and one year return period) equals the drainage system capacity. An extreme rainfall of 30 mm produces a runoff equivalent to fourfold the drainage capacity. It is suggested that the former and latter volumes mentioned above could be harvested by applying the rational method from 18% and 80% rooftops of the commercial and business district area, respectively. Based on the above results, six potential sites can be chosen for RWH with a total roof catchment area of 39,558 m2 and potential rooftop RWH per unit area of 0.033 m3. These results reflect the RWH potential for effective urban runoff management and better water resources utilization. RWH would provide an alternative source of water to tackle the drought phenomenon.

Manmade fragmentation of the Brazilian Atlantic forest poses a serious threat to the biodiversity... more Manmade fragmentation of the Brazilian Atlantic forest poses a serious threat to the biodiversity of the various ecosystems of this unique biome. To counteract this fragmentation process, the Serra dos Órgãos National Park initiated an expansion project aiming at the inclusion of the adjacent Serra da Estrela mountain range into the National Park area. This work analyzes this region from two different points of view to define the most suitable expansion possibility. The protection suitability evaluation assesses the individual landscape patches according to their ecological value. The urbanization suitability evaluation assesses the same landscape patches according to their suitability for future urban growth. To calculate the suitability for protection, as well as urbanization, the method of Multi-Criteria Evaluation (MCE) is applied. The results of the two suitability evaluations are combined and analyzed to identify core areas and conflict zones of the potential expansion area of...

Natural resources journal

In this paper, different aspects of development sustainability will be highlighted by stressing t... more In this paper, different aspects of development sustainability will be highlighted by stressing the fact that even the smartest drivers are necessarily characterized by the continuous uncertainty we all must live with. Different development drivers will be illustrated in the field of agriculture, nature and environment, all attempting to weigh the contradicting, even conflicting parameters of life and decay. Agricultural sustainability drivers will encompass human, cultural, social and political aspects together with components of metabolism, genetics, energy, environment and farm management. It will be concluded that each sustainability approach should be precisely documented using exact parameters and not unproven social or emotional attributes. Quantitative cost to benefit ratios will be proposed as sustainability indicators. In short, sustainability is an ideal state in the area of conflict between environmental change, evolution of life and thermodynamic laws. It cannot be defi...

Ecological Processes, 2014

Introduction: Land use intensification and urbanisation processes are degrading hydrological ecos... more Introduction: Land use intensification and urbanisation processes are degrading hydrological ecosystem services in the Guapi-Macacu watershed of Rio de Janeiro. A proposal to pay farmers to restore natural watershed services might be an alternative to securing the water supply in the long-term for the around 2.5 million urban water users in the study region. This study quantifies the costs of changing current land use patterns to enhance watershed services and compares these costs to the avoided costs associated with water treatment for public supply. Methods: We use farm-household data to estimate the opportunity costs of abandoning current land uses for the recovery of natural vegetation; a process that is very likely to improve water quality in terms of turbidity due to reduced inputs from erosion. Opportunity cost estimates are extrapolated to the watershed scale based on remote sensing land use classifications and vulnerability analysis to identify priority zones for watershed management interventions. To assess the potential demand for watershed services, we analyse water quality and treatment cost data from the main local water treatment plant. Results: Changing agricultural land uses for watershed services provision generally comes at high opportunity costs in our study area near to the metropolis of Rio de Janeiro. Alternative low cost watershed conservation options do exist in the livestock production sector. These options have the potential to directly reduce the amount of sediments and nutrients reaching the water bodies, and in turn decrease the costs of treatment needed for drinking water. Land cover changes at the scale needed to improve water quality will, nonetheless, likely exceed the cost of additional investments in water treatment. Conclusions: The state water utility company's willingness to pay for watershed services alone will not be enough to induce provision of additional watershed services. We conclude that monetary incentives conditioned on specific adjustments to existing production systems could still have a complementary role to play in improving watershed services. However, we note that our willingness to pay analysis focusses on only one of the potentially wide range of ecosystem services provided by natural vegetation in the Guapi-Macacu watershed. Factoring these ecosystem services into the willingness to pay equation is likely to change our assessment in favour of additional conservation action, be it through PES or other policy instruments.

Water Resources Management, 2010

The continuous high demand of water resources for agricultural uses in Jordan is leading to a wat... more The continuous high demand of water resources for agricultural uses in Jordan is leading to a water crisis. A possible partial solution may be to import food which requires large amounts of water to grow instead of cultivating high water consuming crops. Crops such as banana and citrus cause a huge virtual water loss, which can be reduced by cultivating other less water-demanding crops. This paper focuses on analyzing the economic value of cultivating tree fruit from a virtual water perspective. The virtual water calculations in this study depend on the average rainfall, water quota, and the crops' water requirements (CWR). The gross profit to the water use ratio showed that banana has the lowest value 0.085 JD/m 3 , while lemon has the highest value 1.65 JD/m 3 . The calculations show that the average embedded water in fruits varies from about 470 m 3 /ton for grapes to about 2,500 m 3 /ton for dates. Banana and citrus plantations consume about 21 and 71 million cubic meters (MCM) annually, respectively, which represent about 85% of the total water consumption in fruit tree plantation. The virtual water flow estimation embedded in fruits shows that Jordan imports about 77 MCM per year. However it exports about 29 MCM per year. The results were analyzed from an integrated water resources management (IWRM) perspective. The analysis shows that a way to recover some of the water costs involved in, e.g., banana production would be

Hydrological Sciences Journal, 2012

Changes in hydro-meteorological historical records are of considerable importance for future plan... more Changes in hydro-meteorological historical records are of considerable importance for future planning. This study analyses trends of hydro-climatological indices of annual and seasonal precipitation, temperature and discharge in the “Norte Chico” region of Chile (29–32°S), located in the Central Andes. It addresses how these trends possibly impacted on the water resources in a nival regime, typical for arid mountainous regions.

Hydrological Sciences Journal-journal Des Sciences Hydrologiques, 2010

Downscaling of atmosphere–ocean general circulation models (AOGCMs) is necessary to transfer pred... more Downscaling of atmosphere–ocean general circulation models (AOGCMs) is necessary to transfer predictions of potential climate change scenarios to local levels. This is of special interest in dry mountainous areas, which are particularly vulnerable to climate change due to risks of reduced freshwater availability. These areas play a key role in hydrology, since they usually receive the highest local precipitation amounts,

The livelihood possibility across the Nargis Cyclone affected villages are not advanced in tern o... more The livelihood possibility across the Nargis Cyclone affected villages are not advanced in tern of technology as well as in the development of newly formed business. Actually village communities are still straggling to go back their status to before Nargis. Furthermore, communities cannot go advance beyond the pre Nargis condition. The scarcity of fish in the sea, rivers and streams is the challenge of the fishermen. The prawn breeding is main livestock in southern-west part of Delta which is the most seriously affected by Cyclone Nargis. Lack of topping up seed money to repair the breeding fields/ ponds, not know how to prepare these fields properly, no investment for buying seed prawn and rare underground water to use in live stock are the still main challenges for the village communities. As most of the fields are invaded by salinity water from sea, it is not possible to cultivate paddy, therefore the villagers depend on the laborer job hired by outsourced people who got permission to produce salt from these field. The laborers' social protection including status of health and welfare are not good enough.

tropentag.de

The complexity of interactions between numerous environmental and socioeconomic systems in the gl... more The complexity of interactions between numerous environmental and socioeconomic systems in the globalised world requires a deeper understanding of the related systems. Global problems, such as climate change, land degradation, energy crisis or poverty cannot be solved without an understanding of system behaviour and structure. For various broadscale systems, models have been developed. Well known are climate models which are used to generate projections of future climate. For use on regional scales, climate models are downscaled. In addition to climate models, numerous other models have been developed, related to specific topics, such as regional economic models, hydrology models, erosion models, or traffic models. Common aim to all models is the optimisation of systems or the solution of certain problems, respectively. In the hinterland of Rio de Janeiro, many problems, such as biodiversity loss, water pollution, and soil degradation are related to land use intensification processes which are in turn linked to population and economic growth. Against the background of biodiversity conservation in the Atlantic forest, the BMBF project BLUMEN (2002BLUMEN ( -2005 focused on system stability in the agricultural landscape in the mountain region of the Serra dos Órgãos, which still contains a high proportion of small forest fragments. Based on BLUMEN, the current BMBF project DINARIO -Climate Change, Landscape Dynamics, Land Use and Natural Resources in the Atlantic Forest of Rio de Janeiro -integrates lowland landscapes into the research. Furthermore, the development of sustainable land use strategies will be supported by a deeper analysis of water and soil systems.

Hydrological Sciences Journal, 2011