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An exploration of school-community links in enabling environmental learning through food growing : a cross-cultural studyKöhly, Nicolette January 2010 (has links)
Agricultural and educational researchers recognize the critical value of an integrated, multidisciplinary approach to education in building a food-secure world, reducing poverty, and conserving and enhancing natural resources. However, schools generally contribute little to communities in the context of food growing and environmental learning. The main objective of this qualitative research was to explore the role of school-community relationships in enabling environmental learning in the context of food growing activities. Findings suggest that the role of school-community links in enhancing environmental learning is more likely where community members are actively involved in school programs that have an emphasis on an experiential learning approach. However, this depends to a large extent on the availability of parents or concerned community members and their willingness to engage in voluntary school-based activities. Factors that could potentially strengthen the role of school-community links in supporting environmental learning include: allowing space for informal learning, mediating learning in civil society settings, ongoing facilitation by a committed coordinator, community buy-in and accountability, and addressing public interests through tangible benefits. A major challenge is to find an appropriate balance between social justice and practical food security concerns, while remaining true to ecological considerations.
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An analysis of the impact of land registration and certification on the sustainable use of farmlands in northwestern Ethiopia : a case studyErmias Ashagrie Abebe 11 1900 (has links)
This study analyses the impact of land registration and certification scheme on sustainable
use of farmlands in Debre Mawi and Densa Bahta rural kebeles of Amhara region in
northwestern Ethiopia, with a view to contributing to the theoretical debate on tenure security
and more realistic policy advocacy on the sustainable use of farmlands. Within the
framework of qualitative research methodology, the case study approach helps to observe and
understand the relationship between land titling and sustainable use of farmlands in Densa
Bahta and Debre Mawi kebeles of the Amhara region in Ethiopia. Specific methods employed
were focus group discussions, in-depth interviews and observation, complemented by context
analyses of relevant documents. It was found that land titling has contributed to a high
perception of security of land tenure among study respondents. However, results show that
land titling has both positive and negative impacts on sustainable use of farmlands. The
positive impact of land titling is ascribed to its assurance effect and legal obligation imposed
on farmers to adopt proper land management practices. The negative impact of land titling
arises from its failure to address the existing inequality in possession of farmlands among the
village communities. Failure of farmers’ high perceptions of their security of land tenure to
translate into sustainable land use practices has implications for the relative importance of
productive asset endowments, self-efficacy and risk perception on the sustainable use of
farmlands in the Amhara region. Interviewees that follow unsustainable farming practices
were endowed with relatively lower pieces of farmland and disadvantaged in possession of
other productive assets. They also demonstrated a low level of self-efficacy and a risk-averse
attitude to adopting conservation technologies, as they possessed smaller sizes of farmland compared with the village and regional average. The study urges a holistic approach and
comprehensive analytical framework to understand the synergy of several factors that affect the sustainable use of farmlands. / Environmental Sciences / D. Litt. et Phil. (Development Studies)
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Climate change and agricultural production in Limpopo Province : impacts and adaptation optionsMaponya, Phokele Isaac 12 1900 (has links)
The primary aim of my research was to identify the impacts and adaptation options of
climate variability and change on agricultural production in Limpopo province. The
following objectives were identified: To understand the impacts of climate variability and
change on agricultural production in Limpopo province , To assess the impacts of climate
variability and change on agricultural production in Limpopo province and To identify
adaptation measures that reduces the impacts of climate variability and change on
agricultural production in Limpopo province. A representative sample of 300 farmers aged
16- 65+ years (46 percent males and 54 percent females) participated in the study. The
study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn
and 44 percent in Sekhukhune district. The following 11 local municipalities were visited:
Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle
Nkumpi, Blouberg, Aganang, Polokwane, and Molemole.
The Limpopo province is one of the poorest provinces in the country, characterized by
high unemployment rate, poverty and lack of access to a range of resources that frustrate
majority of people ability to secure their livelihoods. In this study the province's
economic, biological and physical environment were highlighted. The study further covers
the province, s farming enterprises, systems, categories, infrastructure as well as other
constraints that maybe facing the emerging farmer in the province.
It is assumed that the majority of farmers in both the Capricorn and Sekhukhune districts
are using different coping and adaptation strategies in order to increase their crop yields.
Literature studies show that climate variability and change adaptation strategies vary from
area to area due to agro ecological zones and the harshness of the effects of climate
variability and change. It has also been noted that climate change is fast pushing the
poorest and most marginalized communities beyond their capacity to respond. This study
draws on lessons learned, experiences, and other existing research on climate change
impacts and adaptation across the globe. It sets out what is needed to enable people living
in poverty to adapt to climate change, and a range of interventions that are available across
climate - sensitive sectors.
The study has provided a literature review of the impact of climate change on the
agricultural sector. In fact, it has documented some of the likely impacts of climate change
based on International, continental, regional, national and provincial agricultural sector.
The study highlighted the impact of climate change also on various climate - sensitive
sectors including understanding water resources, forestry, natural ecosystem human health,
infrastructure and coastal zones. This research also confirmed that being a full time farmer,
gender, information on climate change, information received through extension services
and adaptation to climate change are some of the important determinants of agricultural
production, food scarcity and unemployment. A worrying situation is reviewed globally in
this study and it can be concluded that climate variability and change is affecting every
sector in society and it needs urgent attention. Statistics was used to determine climate
variability and change impact on agricultural production. Results indicate that farmers are
aware that Limpopo province is getting warmer and drier with increased frequency of
droughts, changes in the timing of rains, observed trends oftemperature and precipitation.
The study also presented perceived adaptation strategies used by farmers in Limpopo
province. Some of their perceived adaptation strategies included: (a) Soil management
strategies, (b) Water management strategies and (c) Others like use of subsidies and use of
insurance. Other important adaptation options being used by farmers were also discussed
in this study including different adaptation measures against colds, heat, frost, abnormal
wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and
rainfall. The results of this study are potentially valuable to the agricultural sector
considering the threats that climate change poses across climate sensitive sectors. / Environmental Sciences / D. Phil. (Environmental Management)
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Animal traction and small-scale farming : a Stellenbosch case studyManjengwa, George Munyaradzi 03 1900 (has links)
Thesis (MPhil)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The main aim of this case study was to research the impact of the introduction of oxen for
draught power on Eric Swarts’ Stellenbosch farm. The research objectives were designed to find
out if the oxen helped to improve the quality of the soil, to determine their cost-effectiveness
(compared to a tractor) and other social and managerial constraints and benefits associated with
using them and also to make recommendations for small-scale farmers in developing countries.
The literature review revealed that human society faces many serious sustainability challenges
from ecosystem degradation and global warming, to massive poverty and social inequality. The
global population is growing against a background of decreasing agricultural productivity due to
degraded soils and the increased costs of farming. The adoption of farming methods that enhance
ecosystem services and depend less on external inputs is therefore essential. Animal traction is
still widely used among small-scale farmers in developing countries, but lacks policy and
investment support to make it more efficient. There are currently widespread negative opinions
about animal traction which regard it as a backward or old-fashioned technology. This research
investigated the possibility of animal traction emerging as an affordable, environmentallyfriendly and appropriate technology for small-scale farming.
The research is a case study with a qualitative, ethnographic research design in which participant
observation was key in gathering research data. A cost-benefit analysis (CBA) was carried out to
compare the cost-effectiveness of using oxen to either hiring or buying a tractor.
The findings showed that oxen were a more cost-effective means of draught power than a tractor,
not only in terms of capital costs but also maintenance and operational costs. The manure from
the oxen was both an effective way of supplying crops with essential nutrients and improving
soil biodiversity. The introduction of the oxen presented some challenges to the farmer
concerning knowledge about how animals work and other managerial challenges, but these were
overcome by learning through practice. It was found that the farmer will be able to make
significant savings in soil-amendment costs and he can control the quality of the manure to suit his needs. It was concluded that small-scale farmers who choose animal traction over tractors as
a means of draught power will realise many advantages in return. / AFRIKAANSE OPSOMMING: Die hoof doelwit van dié gevallestudie was om die impak van die ingebruikneming van osse as
trekkrag op Eric Swarts se plaas te Stellenbosch na te vors. Die navorsingsteikens was ontwerp
om uit te vind of die beeste gehelp het om die kwaliteit van die grond te verbeter, om hul
lonendheid vas te stel (in vergelyking met ’n trekker) asook ander sosiale en bestuursbeperkings
en -voordele wat met hul gebruik geassosieer word en ook met voorstelle vir kleinskaalboere in
ontwikkelende lande voorendag te kom.
Die literatuuroorsig navorsing het ontbloot dat die menslike samelewing met vele
volhoubaarheidsuitdagings vanaf ekosistemiese agteruitgang en aardverhitting, tot swaar
armoedigheid en sosiale ongelykhede gekonfronteer word. Die wêreld bevolking groei steeds ten
spyte van die afname in landboukundige produktiwiteit as gevolg van verlaagde grondkwaliteit
en die toenemende landboukoste. Die ingebruikneming van landboumetodes wat ekosistemiese
dienste verhoog en minder staatmaak op eksterne insette is dus noodsaaklik. Dieretrekking word
steeds algemeen in ontwikkelende landebenut, maar dit ontbreek beleids- en
beggingsondersteuning om dit meer doeltreffend te maak. Daar is tans algemeen verbreide
negatiewe sienswyse oor dieretrekksag wat dit as agterlike en oudmodiese tegnologie beskou.
Dié navorsing het ondersoek ingestel om die moontlikheid van dieretrekking as ’n bekostigbare,
omgewingsvriendelike en passende tegnologie vir kleinskaalboerdery vas te stel.
Die navorsing is’n gevallestudie met kwalitatiwe, etnografiese navorsingsontwerp waarin
deelnemerwaarneming kern is tot die insameling van data. ’n Kostewinsteanalise (KWA) was
uitgevoer om die lonenheid van beeste te vergelyk met dié van of die huur of die koop van ’n
trekker.
Die bevindings het getoon dat beeste ’n lonender wyse van trekkrag as trekkers is, nie net in
terme van kapitale koste nie, maar ook onderhouds en bedryfskoste. Die beesmis was beide ’n
doeltreffende manier om die gevasse van nodige voedingstowwe te voorsien asook om
grondbiodiversiteit te verbeter. Die ingebruikneming van beeste het sekere uitdagings vir die
boere ingehou in verband met die kennis van hoe diere werk en ander bestuursuitdagings, maar dié was oorkom deur onderrig uit ondervinding. Daar was bevind dat die boer beduidende
besparings kan maak aan grondaanvullingskoste hierdie jaar en dat hy die kwaliteit van die
beesmis kan beheer om sy behoeftes dien. Die slotsom is dat kleinskaalboere wat kies om
dieretrekking eerder as trekkers as trekkrag te gebruik, sal vele voordele hê.
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Integrating aquaculture with crop systems : an aquaponic enterprise project proposal for the Ntinga Multipurpose Co-Operative in Philippi, South Africavan der Merwe, Marnus 04 1900 (has links)
Thesis (MPhil)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Stellenbosch University was approached to assist with developing a techno-financial model for an urban freshwater aquaculture system in Philippi, Cape Town. Rapidly growing urban areas are predominantly becoming concentrated zones for malnutrition and poverty which require attention. Having enough food to eat does not mean that a family is food secure, the problem is usually associated with the lack of access to nutritious food. Fish is seen as an extremely healthy food which has the potential to effectively support food security and alleviate malnutrition.
Aquaculture is identified as a largely underdeveloped sector in South Africa. It is currently undergoing rapid transition, being promoted by government as an industry that has potential to develop and create jobs, provide food security and grow the South African economy.
Aquaponics- a method to integrate aquaculture with growing crops in a symbiotic system is a highly resource efficient closed-integrated food producing technology which has the potential to benefit from South African biosecurity regulations and climate-geographic characteristics. It is viewed as an effective food production alternative to deal with the challenges of declining high quality freshwater resources and available arable land.
Training and capacity building is important for the development of aquaponic technology. This study explores and identifies the advantages aquaponic technology development would have in South Africa. The study has reviewed and assessed the fundamental principles for aquaculture production and management required for aquaponic systems development and management. A practical case study identifies the daily challenges and design parameters of aquaponic systems. The study is concluded with a techno-financial project proposal which shows how aquaponic systems can be planned. / AFRIKAANSE OPSOMMING: Universiteit Stellenbosch was genader om 'n tegno-finansiele model to ontwikkel vir 'n stedelike akwakultuur plaas in Philippi, Kaapstad. The tempo waarteen die stedelike areas groei ontwikkel kommerwekkende uitdagings soos wanvoeding en armoede.
In hierdie studie is vis geindentifiseer as 'n uiters voedsame aanvulling in die dieet van Suid Afrikaners. Akwakultuur is grootliks agter in terme van ontwikkeling. Dit word beskou as 'n sektor wat groot potensiaal inhou vir Suid Afrika se eknomiese groei, werkskepping en voedselsekuriteit.
Akwaponika is die hersirkulerende integrasie van akwakultuur en hidroponika. Akwaponika hou groot voordele in terme van Suid Afrika se biosekuriteit regulasies and geografiese eienskappe en is 'n effektiewe manier om gebruikte akwakultuur te suiwer.
Opleiding en beplanning word gesien as 'n fundamentele benadering tot suskesvolle akwaponika ontwikkeling. Hierdie studie bestudeer die Suid Afrikaanse omgewing en potensiaal vir akwaponika ontwikkeling. Die fundamentele beginsels van akwakultuur en hidroponika bestuur en produksie is saamgesit wat beskou word as die aanbevele manier om akwaponika te bestuur. 'n Praktiese gevallestudie toon die daaglikse uitdagings aan en gee raad oor daaglikse bestuur van akwaponika stelsels. Die studie word afgesluit met 'n tegno-finansiele model wat wys hoe om 'n akwaponika sisteem te beplan.
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Using nutritional quality of forage and faeces for predicting sustainable livestock and game stocking rates at Pniel Estates in Northern Cape, South AfricaMbatha, Khanyisile R. 03 1900 (has links)
Thesis (PhD)--University of Stellenbosch, 2010. / The aim of the study was to assess the importance of spatial and temporal variation in diet quality and abundance for determining sustainable stocking rates on commercial, communal and game ranches in a semi-arid savanna, with the ultimate goal of avoiding land degradation in the long term, to provide sustainable livelihoods in rangelands and to make policy that will help in managing the available natural resources in the rangelands. Thus, firstly the effects of grazing, fire, nitrogen and water availability on nutritional quality of grass in semi-arid savanna was assessed. Secondly, spatial and temporal variation in plant quantity and quality among management (commercial, communal and game) types and habitat types (open savanna, rocky, shrubby and pans) and stocking rates in different management types were determined. Thirdly, the quality and quantity of variation inside and outside herbivore exclosures among commercial, communal and game management and habitat types in the semi arid savanna were estimated. Fourthly, faecal profiling was used to assess the effects of different management types on diet quality in semi-arid savanna. Lastly, policy based on the results of the present study was formulated.
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Certification standards for sustainable game ranching in the Northern Province, South AfricaDu Toit, Engela A. 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Formal systems of environmental management and certification for activities associated
with extensive land use, relate mainly to forestry. The emergence of forest certification
largely originates from the issue of tropical deforestation and the associated boycott
campaigns against tropical timber. At the United Nations Conference on Environment
and Development in Rio de Janeiro in 1992, a new set of international norms were set in
the form of Forest Principles. These were non-binding and together with international
initiatives, such as the Tropical Forestry Action Programme and the International
Tropical Timber Organisation have failed to decrease deforestation. New efforts to
encourage sustainable forestry through forest certification were made by Non
Governmental Organisations which collaborated with the private sector in developing
new policy instruments. They followed the trend of eco-labelling in an attempt to link
green consumers to producers whose aim it is to improve management practices. The
Forest Stewardship Council (FSC) was established. The FSC system relies on forest
management principles and criteria approved by itself and is based on performance
standards. The International Standards Organisation (ISO) also developed a management
standard based on the principle of continuous improvement. ISO developed the ISO
14001 standard for the certification of Environmental Management Systems which is
applicable to any industry concerned with the environment. From questionnaire surveys
carried out among a sample of private game ranch owners/managers in the Northern
Province, current standards of management were established. It was found that private
owners/managers rely mostly on their own experience and knowledge. Information about
management on game ranches is rarely available and only major concerns and most
visible problems are attended to. Guidelines with standards for an Environmental
Management System (EMS) according to the ISO 14000 series were drawn up from the
results of the surveys and a literature review. A checklist of principles and criteria which
could be used for the certification process was also developed. The final objective is to
attain quality game ranch management which is environmentally sensitive, socially
aware/beneficial and economically viable. This is crucial for the conservation and
preservation of the natural systems in South Africa in which private land owners playa
major role. / AFRIKAANSE OPSOMMING: Formele omgewingsbestuursisteme en sertifisering vir aktiwiteite wat geassosieer word
met ekstensiewe grondbenutting, word hoofsaaklik gekoppel met bosbou. Die konsep
van sertifisering het tot stand gekom as gevolg van die omstredenheid rondom ontbossing
en die gassosieerde sanksies teen tropiese hout. By die Verenigde Nasies Konferensie
oor Omgewing en Ontwikkeling in Rio de Janeiro in 1992 is 'n nuwe stel internasionale
norme daargestel in die vorm van Bosbeginsels. Hierdie was nie-bindend en saam met
internasionale inisiatiewe soos die Tropiese Bos Aksie Program en die Internasionale
Tropiese Hout Organisasie het hulle gefaal om ontbossing te verminder. Nuwe pogings
om volhoubare bosboupraktyke aan te moedig is aangewend nadat Nie-Regering
Organisasies en die privaatsektor saamgewerk het om nuwe beleidsinstrumente te
ontwikkel. Hulle het die neiging vir die "eko-etiket" nagevolg in 'n poging om
omgewingsbewuste verbruikers in kontak te bring met produseerders wat gemoeid is met
verbeterde bestuurspraktyke. Die Forest Stewardship Council (FSC) het tot stand gekom
en hulle sisteem sluit bosbestuursbeginsels en kriteria in wat deur hulleself goedgekeur is
en gebaseer is op werkverrigtingstandaarde. Die Internasionale Standaarde Organisasie
(ISO) het ook 'n bosbestuurstandaard opgestel gebaseer op die beginsel van kontinue
verbetering. ISO het die ISO 14001 standaard opgestel vir Omgewingsbestuursisteme
wat van toepassing gemaak kan word op enige industrie wat gemoeid is met die
omgewmg. Na afhandeling van vraelys opnames onder privaat wildsplaas
eienaars/bestuurders, is daar vasgestel wat die standaard van bestuur tans in die
Noordelike Provinsie is. Privaat eienaarsIbestuurders maak meestal staat op hulle eie
ondervinding en kennis. Inligting oor die bestuur van die wildsplase is nie geredelik
beskikbaar nie en slegs die mees sigbare en grootste probleme word bestuur. 'n Riglyn
met standaarde vir 'n Omgewingsbestuursisteem volgens ISO is opgestel vanaf resultate
van die opnames en 'n literatuurstudie asook 'n "Checklist" wat beginsels en kriteria
insluit wat gebruik kan word in die sertifiseringsproses is ook ontwerp. Die finale doel is
om kwaliteit bestuur te bewerkstellig wat omgewingsensitief, sosiaal bewus/voordelig en
ekonomies lewensvatbaar is. Laasgenoemde is uiters belangrik aangesien privaat
grondeienaars 'n sleutelrol speel in die bewaring en preservering van die natuurlike
sisteme in Suid-Afrika.
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An analysis of the impact of land registration and certification on the sustainable use of farmlands in northwestern Ethiopia : a case studyErmias Ashagrie Abebe 11 1900 (has links)
This study analyses the impact of land registration and certification scheme on sustainable
use of farmlands in Debre Mawi and Densa Bahta rural kebeles of Amhara region in
northwestern Ethiopia, with a view to contributing to the theoretical debate on tenure security
and more realistic policy advocacy on the sustainable use of farmlands. Within the
framework of qualitative research methodology, the case study approach helps to observe and
understand the relationship between land titling and sustainable use of farmlands in Densa
Bahta and Debre Mawi kebeles of the Amhara region in Ethiopia. Specific methods employed
were focus group discussions, in-depth interviews and observation, complemented by context
analyses of relevant documents. It was found that land titling has contributed to a high
perception of security of land tenure among study respondents. However, results show that
land titling has both positive and negative impacts on sustainable use of farmlands. The
positive impact of land titling is ascribed to its assurance effect and legal obligation imposed
on farmers to adopt proper land management practices. The negative impact of land titling
arises from its failure to address the existing inequality in possession of farmlands among the
village communities. Failure of farmers’ high perceptions of their security of land tenure to
translate into sustainable land use practices has implications for the relative importance of
productive asset endowments, self-efficacy and risk perception on the sustainable use of
farmlands in the Amhara region. Interviewees that follow unsustainable farming practices
were endowed with relatively lower pieces of farmland and disadvantaged in possession of
other productive assets. They also demonstrated a low level of self-efficacy and a risk-averse
attitude to adopting conservation technologies, as they possessed smaller sizes of farmland compared with the village and regional average. The study urges a holistic approach and
comprehensive analytical framework to understand the synergy of several factors that affect the sustainable use of farmlands. / Environmental Sciences / D. Litt. et Phil. (Development Studies)
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Assessing opportunities to increase global food production within the safe operating space for human freshwater useJägermeyr, Jonas 02 June 2017 (has links)
Die Landwirtschaft ist heute der wichtigste Treiber der globalen Degradation von Ökosystemen. Es existiert jedoch wenig konkretes Wissen, wie Ökosysteme zu schützen sind und gleichzeitig die Nahrungsproduktion für die wachsende Weltbevölkerung gesichert werden kann. In dieser Dissertation untersuche ich Optimierungsmöglichkeiten im landwirtschaftlichen Wassermanagement. Ich quantifiziere praxisorientierte Verbesserungen der Regenwassernutzung und Optimierungen von Bewässerungssystemen, unter Einhaltung der „environmental flow requirements“ (EFRs). Um diese komplexen Interaktionen zu untersuchen, entwickle ich ein agro-hydrologisches Modell auf Basis detaillierter, mechanistischer Prozessabbildung weiter. Erstens, 39% der derzeitigen Wasserentnahmen für Bewässerung sind nicht nachhaltig und somit auf Kosten der Ökosysteme. Zweitens, solche lokalen Wasserentnahmegrenzen legen nahe, dass die globale Grenze für den menschlichen Wasserverbrauch deutlich niedriger liegt, als bisher angenommen (2800 vs 4000 km3yr-1). Drittens, die Implementierung von EFRs würde die landwirtschaftliche Produktion erheblich beeinträchtigen, mit >20% in stark bewässerten Gebieten. Verbesserte Nutzung des Niederschlagswassers und die Optimierung von Bewässerungssystemen, können die weltweite Nahrungsmittelproduktion allerdings um rund 40% nachhaltig steigern - ausreichend, um die Nahrungsmittellücke der wachsenden Weltbevölkerung bis 2050 zu halbieren. Zusammenfassend stellt diese Arbeit die erste umfassende und systematische Einschätzung globaler Potentiale der nachhaltigen Intensivierung der Landwirtschaft aus der Wasserperspektive dar. Die in dieser Arbeit vorgebrachten innovativen und quantitativen Erkenntnisse legen nahe, dass das Potential der diskutierten Interventionen höhere politische Aufmerksamkeit erfahren sollte. Meine Ergebnisse können eine konkretere Diskussion zur Umsetzung der Sustainable Development Goals untermauern. / Agriculture is today''s most important driver of ecosystem degradation across scales. However, there is little evidence on how to attain the historic twin-challenge of maintaining environmental integrity while producing enough food for a growing world population. In this thesis, I assess opportunities in agricultural water management to reconcile future food needs with environmental limits to water use. I explore solution-oriented ways to improve rainfed and irrigation systems alike, while safeguarding environmental flows (EFRs). To study complex interactions quantitatively, I advanced a state-of-the-art global modeling framework based on detailed, mechanistic process representation. First, a systematic upscaling of EFRs to global coverage indicates that 39% of current freshwater withdrawals for irrigation are unsustainable and occur at the cost of ecosystems. Second, accounting for EFRs indicates that the planetary boundary for freshwater use might be notably lower (2800 vs. 4000 km3yr-1) than expected. Third, maintaining EFRs would significantly affect food production, cutting >20% of total kcal production across intensely irrigated areas. Fourth, improving irrigation systems in combination with optimizing the use of precipitation water, provides effective and accessible measures to compensate for adverse impacts from protecting EFRs and climate change. Such integrated interventions could sustainably intensify global food production (+40% kcal) to the degree sufficient to halve the global food gap by 2050. In conclusion, this thesis provides the first comprehensive and systematic assessment of hitherto largely unquantified water opportunities in sustainable intensification of agriculture. While requiring corroboration by finer-scale research, the innovative quantitative foundation provided in this thesis suggests that farm water management merits a rise in political attention, and it can inform a more comprehensive discussion of related SDG target interactions.
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Indicadores de qualidade de solo e água para a avaliação do uso sustentável da microbacia hidrográfica do Rio Passo Cue, região oeste do estado do Paraná. / Soil and water quality indicators to evaluate the sustainable use of the Rio Passo Cue watershed in western Paraná.Hudson Carlos Lissoni Leonardo 30 September 2003 (has links)
O principal objetivo deste estudo foi avaliar a saúde da microbacia hidrográfica do rio Passo Cue, região oeste do estado do Paraná, por meio do uso de indicadores de qualidade de solo e água. Esse rio é afluente da margem esquerda do reservatório de Itaipu e pertence à bacia hidrográfica do Paraná III. Como indicadores de qualidade de água foram utilizadas variáveis físicas, químicas e biológicas. Para avaliação da qualidade do solo, foram analisados os atributos textura, densidade, porosidade, carbono orgânico, biomassa microbiana, respiração basal, quocientes metabólico e microbiano, macro e micronutrientes, pH e saturação por alumínio. Os indicadores que se mostraram mais eficientes foram a densidade do solo e o quociente metabólico. O solo sob plantio direto apresentou melhor qualidade física, química e biológica em relação ao cultivo mínimo sem rotação de culturas. O solo sob plantio direto apresentou melhor qualidade biológica do que o solo sob fragmento florestal. A qualidade da água na microbacia do rio Passo Cue piorou da montante para a jusante em função do seu uso agropecuário. / The main purpose of this study was to evaluate the conditions of the Passo Cue river watershed, in western Paraná, through soil and water quality indicators. The river is an affluent of the left bank of the Itaipú reservoir and is a part of the Paraná III watershed. Physical, chemical and biological variables were used as water quality indicators. To evaluate the soil quality, texture, density, porosity, organic carbon, microbial biomass, basal respiration, metabolic and microbial quotients, macro and micronutrients, pH and aluminum saturation were analyzed. The more efficient indicators were soil density and metabolic quotient. No-tillage soil showed better physical, chemical and biological quality in relationship with the minimum tillage one with no crop rotation. The soil under no tillage had better biological quality than under forest fragment. The water quality of the Passo Cue river worsened downstream in view of the agricultural use.
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