However, actual rainfall from year to year is irregular and occasionally may be less than, leading to severe reductions in crop yields for both rain-fed and irrigated agriculture.

However, while increases in crop yield are the most obvious applications of modern biotechnology in agriculture, it is also the most difficult one.

However, most vegetation has now been converted to agriculture and forest fragments are now restricted to areas where cultivation is not possible, such as mountain peaks and steep slopes.

However, the mountainous landscape of Chile limits the extent and intensity of agriculture so that arable land corresponds only to 2. 62 % of the total territory.

However, there are many available alternative land use practices that can curtail or limit erosion — such as terrace-building, no-till agriculture, and revegetation of denuded soils.

However, by the time of the Uruguay round, many countries considered the exception of agriculture to be sufficiently glaring that they refused to sign a new deal without some movement on agricultural products.

However, efforts to develop commercial agriculture had limited success, in part because much of Haiti's labor force was employed as seasonal workers in the more-established sugar industries of Cuba and the Dominican Republic.

However, rather than in factories and sweatshops, most child labour occurs in the informal sector, " selling on the street, at work in agriculture or hidden away in houses — far from the reach of official inspectors and from media scrutiny.

However in north-Eastern Europe, the hunting and fishing lifestyle continued into the Medieval period in regions less suited to agriculture.

However, globally human-made pollutants from combustion, construction, mining, agriculture and warfare are increasingly significant in the air pollution equation.

However, the discovery of oats and barley on the plains at about 15, 000 BC suggests that agriculture had already developed at this early date.

However, in more recent times the powers of the Confederation have increased with regard to education, agriculture, health, energy, the environment, organized crime, and narcotics.

However, actual rainfall from year to year is irregular and occasionally may be less than 200 millimeters, leading to severe reductions in crop yields for both rain-fed and irrigated agriculture.

However, since the 1980s, agriculture has been in a state of decline in terms of its share in the total economy.

However, the largest part of the state is used for agriculture ( almost 52 %) and forests ( 25 %).

However, because agriculture has to compete for increasingly scarce water resources with industry and municipal users ( see Water scarcity below ), there is often no alternative for farmers but to use water polluted with urban waste, including sewage, directly to water their crops.

However, there are indications that regional food production has peaked in many world sectors, due to certain strategies associated with intensive agriculture such as groundwater overdrafting and overuse of pesticides and other agricultural chemicals.

However, this theory of the origin of agriculture is controversial in the scientific community.

However, genetically modified B. oleracea crops are not currently used in commercial agriculture.

However, most settlements ended in failure because of the harsh climate and natural conditions, and because of the fact the settlers, previously office workers, were not skilled in agriculture.

However, until the tourism sector in Andorra experienced an upsurge, agriculture had been the mainstay of the economy.

However, both the seafood industry and truck farming declined after mid-century, due to overfishing on the one hand, and the opening of California's Central Valley to irrigated agriculture on the other, but the advent of the large-scale poultry industry filled this gap.

However, all versions agree that Demeter chose to teach Triptolemus the art of agriculture and, from him, the rest of Greece learned to plant and reap crops.

However, its economy remains primarily based on agriculture and providing services to the agricultural workforce.

However bad this number is, before 1991 and the ban on drift-net fisheries, it was estimated that 500, 000 seabirds a year died as a result.

However, the herring fisheries were in decline and the town was taxed heavily to pay for continuing wars.

However, farming carnivorous fish, such as salmon, does not always reduce pressure on wild fisheries, since carnivorous farmed fish are usually fed fishmeal and fish oil extracted from wild forage fish.

However, the regulation of recreational fisheries has been partially delegated under the Fisheries Act to the provinces, with respect to specified species in specific provinces.

However, productive wild fisheries also exist in open oceans, particularly by seamounts, and inland in lakes and rivers.

However, a very small number of species support the majority of the world ’ s fisheries.

However, the approach has been widely criticized as ignoring several key factors involved in fisheries management and has led to the devastating collapse of many fisheries.

However, these fisheries are still subject to the CCAMLR Catch Documentation Scheme ( CDS ) which tracks the trade of toothfish from the point of unloading to the point of final consumption.

However, Monterey Bay states that there is a portion of this species that is certified as sustainable under the MSC standard, and these fisheries are not specifically evaluated in their Seafood Watch report and are not covered under the general ' Avoid ' recommendation.

However, 2005 research on rockfish shows that large, elderly females are far more important than younger fish in maintaining productive fisheries.

However, general fisheries policy remains a " shared competence " of the Union and its member states.

However, some restrictions on fisheries and agriculture take place.

However, European fisheries policy has been unsuccessful so far in achieving sustainability, with 91 % of fisheries on course to be classified as " overfished " by 2015, by which time the EU has committed to international targets for achieving sustainability.

However, while the Department of Conservation has approved the project, and has made substantial environmental monitoring conditions part of the consent, the project also has objectors on the grounds of claimed influences on the local ecosystems and charter fishing ( see the section above on fisheries ).

However, a very small number of species support the majority of the world ’ s fisheries.

However, the department is largely focused on the conservation and allotment of harvests of salt water fisheries on the Atlantic, Pacific and Arctic coasts of Canada.

However, all the assets relating to water supply reservoirs were transferred to the newly created private water companies, even in those cases where there were strong recreational and fisheries interests in the reservoirs.

However, that is changing due to studies by the Georgia fisheries department and Dr. Steve Sammons of Auburn University.

However, it stated that " the large unresolved uncertainties highlight our collective uncertainty about the relative roles of climate change, aquaculture, and fisheries management in determining salmon returns ".

However, linen and domestic shoe production went into decline by the 1820s and the herring fisheries had also declined.

However their argument was somewhat flawed as many fisheries in the world, such as in Antarctic waters are virtually untouched but they are remote from the USA and require very large seagoing vessels.

However, some sections of the neighborhood have been revitalized in recent years, especially those near Frankford Avenue, Kensington's neighbor North of Lehigh Avenue, and Fishtown, an area of Kensington where many Shad fisheries were located, another traditionally working-class neighborhood which has seen rents increase.